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Sample records for vascular cell signaling

  1. VEGF signaling inside vascular endothelial cells and beyond.

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    Eichmann, Anne; Simons, Michael

    2012-04-01

    Vascular endothelial growth factor-A (VEGF-A) has long been recognized as the key regulator of vascular development and function in health and disease. VEGF is a secreted polypeptide that binds to transmembrane tyrosine kinase VEGF receptors on the plasma membrane, inducing their dimerization, activation and assembly of a membrane-proximal signaling complex. Recent studies have revealed that many key events of VEGFR signaling occur inside the endothelial cell and are regulated by endosomal receptor trafficking. Plasma membrane VEGFR interacting molecules, including vascular guidance receptors Neuropilins and Ephrins also regulate VEGFR endocytosis and trafficking. VEGF signaling is increasingly recognized for its roles outside of the vascular system, notably during neural development, and blood vessels regulate epithelial branching morphogenesis. We review here recent advances in our understanding of VEGF signaling and its biological roles. Copyright © 2012 Elsevier Ltd. All rights reserved.

  2. Vascular endothelial growth factor A-stimulated signaling from endosomes in primary endothelial cells.

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    Fearnley, Gareth W; Smith, Gina A; Odell, Adam F; Latham, Antony M; Wheatcroft, Stephen B; Harrison, Michael A; Tomlinson, Darren C; Ponnambalam, Sreenivasan

    2014-01-01

    The vascular endothelial growth factor A (VEGF-A) is a multifunctional cytokine that stimulates blood vessel sprouting, vascular repair, and regeneration. VEGF-A binds to VEGF receptor tyrosine kinases (VEGFRs) and stimulates intracellular signaling leading to changes in vascular physiology. An important aspect of this phenomenon is the spatiotemporal coordination of VEGFR trafficking and intracellular signaling to ensure that VEGFR residence in different organelles is linked to downstream cellular outputs. Here, we describe a series of assays to evaluate the effects of VEGF-A-stimulated intracellular signaling from intracellular compartments such as the endosome-lysosome system. These assays include the initial isolation and characterization of primary human endothelial cells, performing reverse genetics for analyzing protein function; methods used to study receptor trafficking, signaling, and proteolysis; and assays used to measure changes in cell migration, proliferation, and tubulogenesis. Each of these assays has been exemplified with studies performed in our laboratories. In conclusion, we describe necessary techniques for studying the role of VEGF-A in endothelial cell function. © 2014 Elsevier Inc. All rights reserved.

  3. Notch signal reception is required in vascular smooth muscle cells for ductus arteriosus closure

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    Krebs, Luke T.; Norton, Christine R.; Gridley, Thomas

    2017-01-01

    Summary The ductus arteriosus is an arterial vessel that shunts blood flow away from the lungs during fetal life, but normally occludes after birth to establish the adult circulation pattern. Failure of the ductus arteriosus to close after birth is termed patent ductus arteriosus, and is one of the most common congenital heart defects. Our previous work demonstrated that vascular smooth muscle cell expression of the Jag1 gene, which encodes a ligand for Notch family receptors, is essential for postnatal closure of the ductus arteriosus in mice. However, it was not known what cell population was responsible for receiving the Jag1-mediated signal. Here we show, using smooth muscle cell-specific deletion of the Rbpj gene, which encodes a transcription factor that mediates all canonical Notch signaling, that Notch signal reception in the vascular smooth muscle cell compartment is required for ductus arteriosus closure. These data indicate that homotypic vascular smooth muscle cell interactions are required for proper contractile smooth muscle cell differentiation and postnatal closure of the ductus arteriosus in mice. PMID:26742650

  4. Disruption of TGF-β signaling in smooth muscle cell prevents flow-induced vascular remodeling

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    Gao, Fu [Department of Vascular Surgery, Peking University People’s Hospital, Beijing (China); Chambon, Pierre [Institut de Génétique et de Biologie Moléculaire et Cellulaire (CNRS UMR7104, INSERM U596, ULP, Collége de France) and Institut Clinique de la Souris, ILLKIRCH, Strasbourg (France); Tellides, George [Department of Surgery, Interdepartmental Program in Vascular Biology and Therapeutics, Yale University School of Medicine, New Haven, CT (United States); Kong, Wei [Department of Physiology and Pathophysiology, Basic Medical College of Peking University, Beijing (China); Zhang, Xiaoming, E-mail: rmygxgwk@163.com [Department of Vascular Surgery, Peking University People’s Hospital, Beijing (China); Li, Wei [Department of Vascular Surgery, Peking University People’s Hospital, Beijing (China)

    2014-11-07

    Highlights: • TGF-β signaling in SMC contributes to the flow-induced vascular remodeling. • Disruption of TGF-β signaling in SMC can prevent this process. • Targeting SM-specific Tgfbr2 could be a novel therapeutic strategy for vascular remodeling. - Abstract: Transforming growth factor-β (TGF-β) signaling has been prominently implicated in the pathogenesis of vascular remodeling, especially the initiation and progression of flow-induced vascular remodeling. Smooth muscle cells (SMCs) are the principal resident cells in arterial wall and are critical for arterial remodeling. However, the role of TGF-β signaling in SMC for flow-induced vascular remodeling remains unknown. Therefore, the goal of our study was to determine the effect of TGF-β pathway in SMC for vascular remodeling, by using a genetical smooth muscle-specific (SM-specific) TGF-β type II receptor (Tgfbr2) deletion mice model. Mice deficient in the expression of Tgfbr2 (MyhCre.Tgfbr2{sup f/f}) and their corresponding wild-type background mice (MyhCre.Tgfbr2{sup WT/WT}) underwent partial ligation of left common carotid artery for 1, 2, or 4 weeks. Then the carotid arteries were harvested and indicated that the disruption of Tgfbr2 in SMC provided prominent inhibition of vascular remodeling. And the thickening of carotid media, proliferation of SMC, infiltration of macrophage, and expression of matrix metalloproteinase (MMP) were all significantly attenuated in Tgfbr2 disruption mice. Our study demonstrated, for the first time, that the TGF-β signaling in SMC plays an essential role in flow-induced vascular remodeling and disruption can prevent this process.

  5. Notch signaling regulates platelet-derived growth factor receptor-β expression in vascular smooth muscle cells

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    Jin, S.; Hansson, E.M.; Tikka, S.; Lanner, F.; Sahlgren, C.; Farnebo, F.; Baumann, M.; Kalimo, H.; Lendahl, U.

    2008-01-01

    Notch signaling is critically important for proper architecture of the vascular system, and mutations in NOTCH3 are associated with CADASIL, a stroke and dementia syndrome with vascular smooth muscle cell (VSMC) dysfunction. In this report, we link Notch signaling to platelet-derived growth factor

  6. A role of TDIF peptide signaling in vascular cell differentiation is conserved among euphyllophytes

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    Yuki eHirakawa

    2015-11-01

    Full Text Available Peptide signals mediate a variety of cell-to-cell communication crucial for plant growth and development. During Arabidopsis thaliana vascular development, a CLE (CLAVATA3/EMBRYO SURROUNDING REGION-related family peptide hormone, TDIF (tracheary element differentiation inhibitory factor, regulates procambial cell fate by its inhibitory activity on xylem differentiation. To address if this activity is conserved among vascular plants, we performed comparative analyses of TDIF signaling in non-flowering vascular plants (gymnosperms, monilophytes and lycophytes. We identified orthologs of TDIF/CLE as well as its receptor TDR/PXY (TDIF RECEPTOR/PHLOEM INTERCALATED WITH XYLEM in Ginkgo biloba, Adiantum aethiopicum and Selaginella kraussiana by RACE-PCR. The predicted TDIF peptide sequences in seed plants and monilophytes were identical to that of A. thaliana TDIF. We examined the effects of exogenous CLE peptide-motif sequences of TDIF in these species. We found that liquid culturing of dissected leaves or shoots was useful for examining TDIF activity during vascular development. TDIF treatment suppressed xylem/tracheary element differentiation of procambial cells in G. bioloba and A. aethiopicum leaves. In contrast, neither TDIF nor putative endogenous TDIF inhibited xylem differentiation in developing shoots and rhizophores of S. kraussiana. These data suggest that activity of TDIF in vascular development is conserved among extant euphyllophytes. In addition to the conserved function, via liquid culturing of its bulbils, we found a novel inhibitory activity on root growth in the monilophyte Asplenium x lucrosum suggesting lineage-specific co-option of peptide signaling occurred during the evolution of vascular plant organs.

  7. ER Alpha Rapid Signaling Is Required for Estrogen Induced Proliferation and Migration of Vascular Endothelial Cells.

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    Qing Lu

    Full Text Available Estrogen promotes the proliferation and migration of vascular endothelial cells (ECs, which likely underlies its ability to accelerate re-endothelialization and reduce adverse remodeling after vascular injury. In previous studies, we have shown that the protective effects of E2 (the active endogenous form of estrogen in vascular injury require the estrogen receptor alpha (ERα. ERα transduces the effects of estrogen via a classical DNA binding, "genomic" signaling pathway and via a more recently-described "rapid" signaling pathway that is mediated by a subset of ERα localized to the cell membrane. However, which of these pathways mediates the effects of estrogen on endothelial cells is poorly understood. Here we identify a triple point mutant version of ERα (KRR ERα that is specifically defective in rapid signaling, but is competent to regulate transcription through the "genomic" pathway. We find that in ECs expressing wild type ERα, E2 regulates many genes involved in cell migration and proliferation, promotes EC migration and proliferation, and also blocks the adhesion of monocytes to ECs. ECs expressing KRR mutant ERα, however, lack all of these responses. These observations establish KRR ERα as a novel tool that could greatly facilitate future studies into the vascular and non-vascular functions of ERα rapid signaling. Further, they support that rapid signaling through ERα is essential for many of the transcriptional and physiological responses of ECs to E2, and that ERα rapid signaling in ECs, in vivo, may be critical for the vasculoprotective and anti-inflammatory effects of estrogen.

  8. Redox signaling in cardiovascular pathophysiology: A focus on hydrogen peroxide and vascular smooth muscle cells

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    Chang Hyun Byon

    2016-10-01

    Full Text Available Oxidative stress represents excessive intracellular levels of reactive oxygen species (ROS, which plays a major role in the pathogenesis of cardiovascular disease. Besides having a critical impact on the development and progression of vascular pathologies including atherosclerosis and diabetic vasculopathy, oxidative stress also regulates physiological signaling processes. As a cell permeable ROS generated by cellular metabolism involved in intracellular signaling, hydrogen peroxide (H2O2 exerts tremendous impact on cardiovascular pathophysiology. Under pathological conditions, increased oxidase activities and/or impaired antioxidant systems results in uncontrolled production of ROS. In a pro-oxidant environment, vascular smooth muscle cells (VSMC undergo phenotypic changes which can lead to the development of vascular dysfunction such as vascular inflammation and calcification. Investigations are ongoing to elucidate the mechanisms for cardiovascular disorders induced by oxidative stress. This review mainly focuses on the role of H2O2 in regulating physiological and pathological signals in VSMC.

  9. Estrogen-induced DNA synthesis in vascular endothelial cells is mediated by ROS signaling

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    Felty Quentin

    2006-04-01

    to be dose dependent. Conclusion We have shown that estrogen exposure stimulates the rapid production of intracellular ROS and they are involved in growth signaling of endothelial cells. It appears that the early estrogen signaling does not require estrogen receptor genomic signaling because we can inhibit estrogen-induced DNA synthesis by antioxidants. Findings of this study may further expand research defining the underlying mechanism of how estrogen may promote vascular lesions. It also provides important information for the design of new antioxidant-based drugs or new antioxidant gene therapy to protect the cardiovascular health of individuals sensitive to estrogen.

  10. S1P receptor signalling and RGS proteins; expression and function in vascular smooth muscle cells and transfected CHO cells

    NARCIS (Netherlands)

    Hendriks-Balk, Mariëlle C.; van Loenen, Pieter B.; Hajji, Najat; Michel, Martin C.; Peters, Stephan L. M.; Alewijnse, Astrid E.

    2009-01-01

    Sphingosine-1-phosphate (S1P) signalling via G protein-coupled receptors is important for the regulation of cell function and differentiation. Specific Regulators of G protein Signalling (RGS) proteins modulate the function of these receptors in many cell types including vascular smooth muscle cells

  11. Hepatocyte growth factor triggers signaling cascades mediating vascular smooth muscle cell migration

    NARCIS (Netherlands)

    Taher, Taher E. I.; Derksen, Patrick W. B.; de Boer, Onno J.; Spaargaren, Marcel; Teeling, Peter; van der Wal, Allard C.; Pals, Steven T.

    2002-01-01

    A key event in neointima formation and atherogenesis is the migration of vascular smooth muscle cells (VSMCs) into the intima. This is controlled by cytokines and extracellular matix (ECM) components within the microenvironment of the diseased vessel wall. At present, these signals have only been

  12. Triiodothyronine Potentiates Vasorelaxation via PKG/VASP Signaling in Vascular Smooth Muscle Cells

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    Sherin Samuel

    2017-04-01

    Full Text Available Background/Aims: Vascular relaxation caused by Triiodothyronine (T3 involves direct activation of endothelial cells (EC and vascular smooth muscle cells (VSMC. Activation of protein kinase G (PKG has risen as a novel contributor to the vasorelaxation mechanism triggered by numerous stimuli. We hypothesize that T3-induced vasorelaxation involves PKG/vasodilator-stimulated phosphoprotein (VASP signaling pathway in VSMC. Methods: Human aortic endothelial cells (HAEC and VSMC were treated with T3 for short (2 to 60 minutes and long term (24 hours. Nitric oxide (NO production was measured using DAF-FM. Expression of protein targets was determined using western blot. For functional studies, rat aortas were isolated and treated with T3 for 20 minutes and mounted in a wire myograph. Relaxation was measured by a concentration-dependent response to acetylcholine (ACh and sodium nitroprusside (SNP. Results: Aortas stimulated with T3 exhibited augmented sensitivity to ACh and SNP-induced relaxation, endothelium-dependent and endothelium-independent responses, respectively. T3 directly increased vasorelaxation, which was abolished in the presence of a PKG inhibitor. T3 markedly induced phosphorylation of Akt, eNOS and consequently increased NO production in EC. Likewise, T3 induced phosphorylation of VASP at serine 239 via the PKG pathway in VSMC. Conclusion: Our findings have uncovered a PKG/VASP signaling pathway in VSMC as a key molecular mechanism underlying T3-induced vascular relaxation.

  13. Triiodothyronine Potentiates Vasorelaxation via PKG/VASP Signaling in Vascular Smooth Muscle Cells.

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    Samuel, Sherin; Zhang, Kuo; Tang, Yi-Da; Gerdes, A Martin; Carrillo-Sepulveda, Maria Alicia

    2017-01-01

    Vascular relaxation caused by Triiodothyronine (T3) involves direct activation of endothelial cells (EC) and vascular smooth muscle cells (VSMC). Activation of protein kinase G (PKG) has risen as a novel contributor to the vasorelaxation mechanism triggered by numerous stimuli. We hypothesize that T3-induced vasorelaxation involves PKG/vasodilator-stimulated phosphoprotein (VASP) signaling pathway in VSMC. Human aortic endothelial cells (HAEC) and VSMC were treated with T3 for short (2 to 60 minutes) and long term (24 hours). Nitric oxide (NO) production was measured using DAF-FM. Expression of protein targets was determined using western blot. For functional studies, rat aortas were isolated and treated with T3 for 20 minutes and mounted in a wire myograph. Relaxation was measured by a concentration-dependent response to acetylcholine (ACh) and sodium nitroprusside (SNP). Aortas stimulated with T3 exhibited augmented sensitivity to ACh and SNP-induced relaxation, endothelium-dependent and endothelium-independent responses, respectively. T3 directly increased vasorelaxation, which was abolished in the presence of a PKG inhibitor. T3 markedly induced phosphorylation of Akt, eNOS and consequently increased NO production in EC. Likewise, T3 induced phosphorylation of VASP at serine 239 via the PKG pathway in VSMC. Our findings have uncovered a PKG/VASP signaling pathway in VSMC as a key molecular mechanism underlying T3-induced vascular relaxation. © 2017 The Author(s)Published by S. Karger AG, Basel.

  14. Androgen receptor signalling in Vascular Endothelial cells is dispensable for spermatogenesis and male fertility

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    O'Hara Laura

    2012-01-01

    Full Text Available Abstract Background Androgen signalling is essential both for male development and function of the male reproductive system in adulthood. Within the adult testis, Germ cells (GC do not express androgen receptor (AR suggesting androgen-mediated promotion of spermatogenesis must act via AR-expressing somatic cell-types. Several recent studies have exploited the Cre/lox system of conditional gene-targeting to ablate AR function from key somatic cell-types in order to establish the cell-specific role of AR in promotion of male fertility. In this study, we have used a similar approach to specifically ablate AR-signalling from Vascular Endothelial (VE cells, with a view to defining the significance of androgen signalling within this cell-type on spermatogenesis. Findings AR expression in VE cells of the testicular vasculature was confirmed using an antibody against AR. A Cre-inducible fluorescent reporter line was used to empirically establish the utility of a mouse line expressing Cre Recombinase driven by the Tie2-Promoter, for targeting VE cells. Immunofluorescent detection revealed expression of YFP (and therefore Cre Recombinase function limited to VE cells and an interstitial population of cells, believed to be macrophages, that did not express AR. Mating of Tie2-Cre males to females carrying a floxed AR gene produced Vascular Endothelial Androgen Receptor Knockout (VEARKO mice and littermate controls. Ablation of AR from all VE cells was confirmed; however, no significant differences in bodyweight or reproductive tissue weights could be detected in VEARKO animals and spermatogenesis and fertility was unaffected. Conclusions We demonstrate the successful generation and empirical validation of a cell-specific knockout of AR from VE cells, and conclude that AR expression in VE cells is not essential for spermatogenesis or male fertility.

  15. Acetylbritannilactone Modulates Vascular Endothelial Growth Factor Signaling and Regulates Angiogenesis in Endothelial Cells.

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    Jingshan Zhao

    Full Text Available The present study was conducted to determine the effects of 1-O-acetylbritannilactone (ABL, a compound extracted from Inula britannica L., on vascular endothelial growth factor (VEGF signaling and angiogenesis in endothelial cells (ECs. We showed that ABL promotes VEGF-induced cell proliferation, growth, migration, and tube formation in cultured human ECs. Furthermore, the modulatory effect of ABL on VEGF-induced Akt, MAPK p42/44, and p38 phosphorylation, as well as on upstream VEGFR-2 phosphorylation, were associated with VEGF-dependent Matrigel angiogenesis in vivo. In addition, animals treated with ABL (26 mg/kg/day recovered blood flow significantly earlier than control animals, suggesting that ABL affects ischemia-mediated angiogenesis and arteriogenesis in vivo. Finally, we demonstrated that ABL strongly reduced the levels of VEGFR-2 on the cell surface, enhanced VEGFR-2 endocytosis, which consistent with inhibited VE-cadherin, a negative regulator of VEGF signaling associated with VEGFR-2 complex formation, but did not alter VE-cadherin or VEGFR-2 expression in ECs. Our results suggest that ABL may serve as a novel therapeutic intervention for various cardiovascular diseases, including chronic ischemia, by regulating VEGF signaling and modulating angiogenesis.

  16. The neuropeptide catestatin promotes vascular smooth muscle cell proliferation through the Ca{sup 2+}-calcineurin-NFAT signaling pathway

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    Guo, Xiaoxia [Department of Cardiology, People' s Hospital, Peking University, No. 11 South Avenue, Xi Zhi Men Xicheng District, Beijing 100044 (China); Zhou, Chunyan, E-mail: chunyanzhou@bjmu.edu.cn [Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Peking University, 38 Xueyuan Road, Haidian District, Beijing 100191 (China); Sun, Ningling, E-mail: nlsun@263.net [Department of Cardiology, People' s Hospital, Peking University, No. 11 South Avenue, Xi Zhi Men Xicheng District, Beijing 100044 (China)

    2011-04-22

    Highlights: {yields} Catestatin stimulates proliferation of vascular smooth muscle cells in a dose-dependent manner. {yields} Catestatin provokes sustained increase in intracellular Ca{sup 2+}. {yields} Catestatin produces increased activation of calcineurin and promotes NFATc1 translocation into the nucleus. -- Abstract: The Chromogranin A-derived neuropeptide catestatin is an endogenous nicotinic cholinergic antagonist that acts as a pleiotropic hormone. Since catestatin shares several functions with other members derived from the chromogranin/secretogranin protein family and other neuropeptides which exert proliferative effects on vascular smooth muscle cells (VSMCs), we therefore hypothesized that catestatin would regulate VSMC proliferation. The present study demonstrates that catestatin caused a dose-dependent induction of proliferation in rat aortic smooth muscle cells and furthermore evoked a sustained increase in intracellular calcium. This subsequently leaded to enhanced activation of the Ca{sup 2+}/calmodulin-dependent phosphatase, calcineurin and resulted in an activation of the Ca{sup 2+}-dependent transcription factor, nuclear factor of activated T cells (NFAT), initiating transcription of proliferative genes. In addition, cyclosporin A (CsA), a potent inhibitor of calcineurin, abrogated catestatin-mediated effect on VSMCs, indicating that the calcineurin-NFAT signaling is strongly required for catestatin-induced growth of VSMCs. The present study establishes catestatin as a novel proliferative cytokine on vascular smooth muscle cells and this effect is mediated by the Ca{sup 2+}-calcineurin-NFAT signaling pathway.

  17. Matrix Metalloproteinases: Inflammatory Regulators of Cell Behaviors in Vascular Formation and Remodeling

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    Qishan Chen

    2013-01-01

    Full Text Available Abnormal angiogenesis and vascular remodeling contribute to pathogenesis of a number of disorders such as tumor, arthritis, atherosclerosis, restenosis, hypertension, and neurodegeneration. During angiogenesis and vascular remodeling, behaviors of stem/progenitor cells, endothelial cells (ECs, and vascular smooth muscle cells (VSMCs and its interaction with extracellular matrix (ECM play a critical role in the processes. Matrix metalloproteinases (MMPs, well-known inflammatory mediators are a family of zinc-dependent proteolytic enzymes that degrade various components of ECM and non-ECM molecules mediating tissue remodeling in both physiological and pathological processes. MMPs including MMP-1, MMP-2, MMP-3, MMP-7, MMP-8, MMP-9, MMP-12, and MT1-MMP, are stimulated and activated by various stimuli in vascular tissues. Once activated, MMPs degrade ECM proteins or other related signal molecules to promote recruitment of stem/progenitor cells and facilitate migration and invasion of ECs and VSMCs. Moreover, vascular cell proliferation and apoptosis can also be regulated by MMPs via proteolytically cleaving and modulating bioactive molecules and relevant signaling pathways. Regarding the importance of vascular cells in abnormal angiogenesis and vascular remodeling, regulation of vascular cell behaviors through modulating expression and activation of MMPs shows therapeutic potential.

  18. CaMKII in Vascular Signalling: "Friend or Foe"?

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    Ebenebe, Obialunanma V; Heather, Alison; Erickson, Jeffrey R

    2018-05-01

    Signalling mechanisms within and between cells of the vasculature enable function and maintain homeostasis. However, a number of these mechanisms also contribute to the pathophysiology of vascular disease states. The multifunctional signalling molecule calcium/calmodulin-dependent kinase II (CaMKII) has been shown to have critical functional effects in many tissue types. For example, CaMKII is known to have a dual role in cardiac physiology and pathology. The function of CaMKII within the vasculature is incompletely understood, but emerging evidence points to potential physiological and pathological roles. This review discusses the evidence for CaMKII signalling within the vasculature, with the aim to better understand both positive and potentially deleterious effects of CaMKII activation in vascular tissue. Copyright © 2017 Australian and New Zealand Society of Cardiac and Thoracic Surgeons (ANZSCTS) and the Cardiac Society of Australia and New Zealand (CSANZ). Published by Elsevier B.V. All rights reserved.

  19. Open the gates: vascular neurocrine signaling mobilizes hematopoietic stem and progenitor cells.

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    Itkin, Tomer; Gómez-Salinero, Jesús María; Rafii, Shahin

    2017-12-01

    Mobilization of hematopoietic stem and progenitor cells (HSPCs) from the bone marrow (BM) into the peripheral blood is a complex process that is enhanced dramatically under stress-induced conditions. A better understanding of how the mobilization process is regulated will likely facilitate the development of improved clinical protocols for stem cell harvesting and transplantation. In this issue of the JCI, Singh et al. (1) showed that the truncated cleaved form of neurotransmitter neuropeptide Y (NPY) actively promotes a breach of BM vascular sinusoidal portals, thereby augmenting HSPC trafficking to the circulation. The authors report a previously unrecognized axis, in which expression of the enzyme dipeptidylpeptidase-4 (DPP4)/CD26 by endothelial cells activates NPY-mediated signaling by increasing the bioavailability of the truncated form of NPY. These findings underscore the importance of and urgency to develop pharmacological therapies that target the vasculature and regulate diverse aspects of hematopoiesis, such as HSPC trafficking, in steady-state and stress-induced conditions.

  20. Nitric oxide signaling and the cross talk with prostanoids pathways in vascular system.

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    Silva, Bruno R; Paula, Tiago D; Paulo, Michele; Bendhack, Lusiane M

    2016-12-28

    This review provides an overview of the cellular signaling of nitric oxide (NO) and prostanoids in vascular cells and the possible cross talk between their pathways, mainly in hypertension, since the imbalance of these two systems has been attributed to development of some cardiovascular diseases. It also deals with the modulation of vasodilation induced by NO donors. NO is a well-known second messenger involved in many cellular functions. In the vascular system, the NO produced by endothelial NO-synthase (eNOS) or released by NO donors acts in vascular smooth muscle cells, the binding of NO to Fe2+-heme of soluble guanylyl-cyclase (sGC) activates sGC and the production of cyclic guanosine-3-5-monophosphate (cGMP). The second messenger (cGMP) activates protein kinase G and the signaling cascade, including K+ channels. Activation of K+ channels leads to cell membrane hyperpolarization and Ca2+ channels blockade, which induce vascular relaxation. Moreover, the enzyme cyclooxygenase (COX) is also an important regulator of the vascular function by prostanoids production such as thromboxane A2 (TXA2) and prostacyclin (PGI2), which classically induce contraction and relaxation, respectively. Additionaly, studies indicate that the activity of both enzymes can be modulated by their products and reactive oxygen species (ROS) in cardiovascular diseases such as hypertension. The interaction of NO with cellular molecules, particularly the reaction of NO with ROS, determines the biological mechanisms of action and short half-life of NO. We have been working on the vascular effects of ruthenium-derived complexes that release NO. Our research group has published works on the vasodilating effects of ruthenium-derived NO donors and the mechanisms of vascular cells involved in the relaxation of the vascular smooth muscle in health and hypertensive rats. In our previous studies, we have compared the new NO donors synthesized by our group to SNP. It shows the cellular signaling of NO

  1. Vinpocetine Attenuates the Osteoblastic Differentiation of Vascular Smooth Muscle Cells.

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    Yun-Yun Ma

    Full Text Available Vascular calcification is an active process of osteoblastic differentiation of vascular smooth muscle cells; however, its definite mechanism remains unknown. Vinpocetine, a derivative of the alkaloid vincamine, has been demonstrated to inhibit the high glucose-induced proliferation of vascular smooth muscle cells; however, it remains unknown whether vinpocetine can affect the osteoblastic differentiation of vascular smooth muscle cells. We hereby investigated the effect of vinpocetine on vascular calcification using a beta-glycerophosphate-induced cell model. Our results showed that vinpocetine significantly reduced the osteoblast-like phenotypes of vascular smooth muscle cells including ALP activity, osteocalcin, collagen type I, Runx2 and BMP-2 expression as well as the formation of mineralized nodule. Vinpocetine, binding to translocation protein, induced phosphorylation of extracellular signal-related kinase and Akt and thus inhibited the translocation of nuclear factor-kappa B into the nucleus. Silencing of translocator protein significantly attenuated the inhibitory effect of vinpocetine on osteoblastic differentiation of vascular smooth muscle cells. Taken together, vinpocetine may be a promising candidate for the clinical therapy of vascular calcification.

  2. Sorafenib inhibits tumor growth and vascularization of rhabdomyosarcoma cells by blocking IGF-1R-mediated signaling

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    Wessen Maruwge

    2008-11-01

    Full Text Available Wessen Maruwge1, Pádraig D’Arcy1, Annika Folin1,2, Slavica Brnjic1, Johan Wejde1, Anthony Davis1, Fredrik Erlandsson3, Jonas Bergh1,2, Bertha Brodin11Department of Oncology and Pathology, Karolinska Institutet, Stockholm, Sweden; 2Radiumhemmet, Karolinska University Hospital, Stockholm, Sweden; 3Bayer Pharmaceutical Corporation, SwedenAbstract: The growth of many soft tissue sarcomas is dependent on aberrant growth factor signaling, which promotes their proliferation and motility. With this in mind, we evaluated the effect of sorafenib, a receptor tyrosine kinase inhibitor, on cell growth and apoptosis in sarcoma cell lines of various histological subtypes. We found that sorafenib effectively inhibited cell proliferation in rhabdomyosarcoma, synovial sarcoma and Ewing’s sarcoma with IC50 values <5 µM. Sorafenib effectively induced growth arrest in rhabdomyosarcoma cells, which was concurrent with inhibition of Akt and Erk signaling. Studies of ligand-induced phosphorylation of Erk and Akt in rhabdomyosarcoma cells showed that insulin-like growth factor-1 is a potent activator, which can be blocked by treatment with sorafenib. In vivo sorafenib treatment of rhabdomyosarcoma xenografts had a significant inhibitory effect on tumor growth, which was associated with inhibited vascularization and enhanced necrosis in the adjacent tumor stroma. Our results demonstrate that in vitro and in vivo growth of rhabdomyosarcoma can be suppressed by treatment with sorafenib, and suggests the possibilities of using sorafenib as a potential adjuvant therapy for the treatment of rhabdomyosarcoma.Keywords: soft tissue sarcoma, kinase inhibitors, targeted therapy, vascularization

  3. Piperlongumine inhibits atherosclerotic plaque formation and vascular smooth muscle cell proliferation by suppressing PDGF receptor signaling

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    Son, Dong Ju [Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA (United States); Division of Cardiology, Department of Medicine, Emory University, Atlanta, GA (United States); Kim, Soo Yeon [Division of Life Science, Korea Basic Science Institute, Daejeon (Korea, Republic of); Han, Seong Su [University of Iowa Carver College of Medicine, Department of Pathology, Iowa City, IA (United States); Kim, Chan Woo [Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA (United States); Division of Cardiology, Department of Medicine, Emory University, Atlanta, GA (United States); Department of Bioinspired Science, Ehwa Womans University, Seoul (Korea, Republic of); Kumar, Sandeep [Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA (United States); Division of Cardiology, Department of Medicine, Emory University, Atlanta, GA (United States); Park, Byeoung Soo [Nanotoxtech Co., Ansan (Korea, Republic of); Lee, Sung Eun [Division of Applied Biology and Chemistry, Kyungpook National University, Daegu (Korea, Republic of); Yun, Yeo Pyo [College of Pharmacy, Chungbuk National University, Cheongju (Korea, Republic of); Jo, Hanjoong, E-mail: hjo@emory.edu [Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA (United States); Division of Cardiology, Department of Medicine, Emory University, Atlanta, GA (United States); Department of Bioinspired Science, Ehwa Womans University, Seoul (Korea, Republic of); Park, Young Hyun, E-mail: pyh012@sch.ac.kr [Department of Food Science and Nutrition, College of Natural Sciences, Soonchunhyang University, Asan (Korea, Republic of)

    2012-10-19

    Highlights: Black-Right-Pointing-Pointer Anti-atherogenic effect of PL was examined using partial carotid ligation model in ApoE KO mice. Black-Right-Pointing-Pointer PL prevented atherosclerotic plaque development, VSMCs proliferation, and NF-{kappa}B activation. Black-Right-Pointing-Pointer Piperlongumine reduced vascular smooth muscle cell activation through PDGF-R{beta} and NF-{kappa}B-signaling. Black-Right-Pointing-Pointer PL may serve as a new therapeutic molecule for atherosclerosis treatment. -- Abstract: Piperlongumine (piplartine, PL) is an alkaloid found in the long pepper (Piper longum L.) and has well-documented anti-platelet aggregation, anti-inflammatory, and anti-cancer properties; however, the role of PL in prevention of atherosclerosis is unknown. We evaluated the anti-atherosclerotic potential of PL in an in vivo murine model of accelerated atherosclerosis and defined its mechanism of action in aortic vascular smooth muscle cells (VSMCs) in vitro. Local treatment with PL significantly reduced atherosclerotic plaque formation as well as proliferation and nuclear factor-kappa B (NF-{kappa}B) activation in an in vivo setting. PL treatment in VSMCs in vitro showed inhibition of migration and platelet-derived growth factor BB (PDGF-BB)-induced proliferation to the in vivo findings. We further identified that PL inhibited PDGF-BB-induced PDGF receptor beta activation and suppressed downstream signaling molecules such as phospholipase C{gamma}1, extracellular signal-regulated kinases 1 and 2 and Akt. Lastly, PL significantly attenuated activation of NF-{kappa}B-a downstream transcriptional regulator in PDGF receptor signaling, in response to PDGF-BB stimulation. In conclusion, our findings demonstrate a novel, therapeutic mechanism by which PL suppresses atherosclerosis plaque formation in vivo.

  4. The adaptor Lnk (SH2B3): an emerging regulator in vascular cells and a link between immune and inflammatory signaling.

    Science.gov (United States)

    Devallière, Julie; Charreau, Béatrice

    2011-11-15

    A better knowledge of the process by which inflammatory extracellular signals are relayed from the plasma membrane to specific intracellular sites is a key step to understand how inflammation develops and how it is regulated. This review focuses on Lnk (SH2B3) a member, with SH2B1 and SH2B2, of the SH2B family of adaptor proteins that influences a variety of signaling pathways mediated by Janus kinase and receptor tyrosine kinases. SH2B adaptor proteins contain conserved dimerization, pleckstrin homology, and SH2 domains. Initially described as a regulator of hematopoiesis and lymphocyte differentiation, Lnk now emerges as a key regulator in hematopoeitic and non hematopoeitic cells such as endothelial cells (EC) moderating growth factor and cytokine receptor-mediated signaling. In EC, Lnk is a negative regulator of TNF signaling that reduce proinflammatory phenotype and prevent EC from apoptosis. Lnk is a modulator in integrin signaling and actin cytoskeleton organization in both platelets and EC with an impact on cell adhesion, migration and thrombosis. In this review, we discuss some recent insights proposing Lnk as a key regulator of bone marrow-endothelial progenitor cell kinetics, including the ability to cell growth, endothelial commitment, mobilization, and recruitment for vascular regeneration. Finally, novel findings also provided evidences that mutations in Lnk gene are strongly linked to myeloproliferative disorders but also autoimmune and inflammatory syndromes where both immune and vascular cells display a role. Overall, these studies emphasize the importance of the Lnk adaptor molecule not only as prognostic marker but also as potential therapeutic target. Copyright © 2011 Elsevier Inc. All rights reserved.

  5. Oxytocin receptors expressed and coupled to Ca2+ signalling in a human vascular smooth muscle cell line.

    Science.gov (United States)

    Yazawa, H; Hirasawa, A; Horie, K; Saita, Y; Iida, E; Honda, K; Tsujimoto, G

    1996-03-01

    1. In a human vascular smooth muscle cell line (HVSMC), binding experiments with [3H]-arginine8-vasopressin (AVP) have shown the existence of a homogeneous population of binding sites with affinity (Kd value) of 0.65 nM and a maximum number of binding sites (Bmax) of 122 fmol mg-1 protein. 2. Nonlabelled compounds compete for [3H]-AVP binding in the HVSMC membrane with an order of potency of oxytocin > lyspressin > or = AVP > Thr4, Gly7-oxytocin > (beta-mercapto-beta-beta-cyclopentamethylenepropionyl-O-Me Tyr2, Arg8) vasopressin > desmopressin > OPC21268 > OPC31260. This order was markedly different from that observed in rat vascular smooth muscle cells (A10), a well-established V1A receptor system. 3. In HVSMC both oxytocin and AVP increased inositol 1,4,5-trisphosphate (IP3) production and [Ca2+]i response, but the efficacy of the responses was greater for oxytocin than AVP. 4. Reverse transcription-polymerase chain reaction (RT-PCR) assay detected only oxytocin receptor but not V1A or V2 receptors in HVSMC, whereas only V1A receptors were found in A10 cells. 5. In conclusion, in HVSMC only oxytocin receptors are expressed among the vasopressin receptor family, and they coupled to phosphatidyl inositol (PI) turnover/Ca2+ signalling. This unexpected observation should provide new insight into the functional role of the oxytocin receptor in a human vascular smooth muscle cell line.

  6. High fructose-mediated attenuation of insulin receptor signaling does not affect PDGF-induced proliferative signaling in vascular smooth muscle cells.

    Science.gov (United States)

    Osman, Islam; Poulose, Ninu; Ganapathy, Vadivel; Segar, Lakshman

    2016-11-15

    Insulin resistance is associated with accelerated atherosclerosis. Although high fructose is known to induce insulin resistance, it remains unclear as to how fructose regulates insulin receptor signaling and proliferative phenotype in vascular smooth muscle cells (VSMCs), which play a major role in atherosclerosis. Using human aortic VSMCs, we investigated the effects of high fructose treatment on insulin receptor substrate-1 (IRS-1) serine phosphorylation, insulin versus platelet-derived growth factor (PDGF)-induced phosphorylation of Akt, S6 ribosomal protein, and extracellular signal-regulated kinase (ERK), and cell cycle proteins. In comparison with PDGF (a potent mitogen), neither fructose nor insulin enhanced VSMC proliferation and cyclin D1 expression. d-[ 14 C(U)]fructose uptake studies revealed a progressive increase in fructose uptake in a time-dependent manner. Concentration-dependent studies with high fructose (5-25mM) showed marked increases in IRS-1 serine phosphorylation, a key adapter protein in insulin receptor signaling. Accordingly, high fructose treatment led to significant diminutions in insulin-induced phosphorylation of downstream signaling components including Akt and S6. In addition, high fructose significantly diminished insulin-induced ERK phosphorylation. Nevertheless, high fructose did not affect PDGF-induced key proliferative signaling events including phosphorylation of Akt, S6, and ERK and expression of cyclin D1 protein. Together, high fructose dysregulates IRS-1 phosphorylation state and proximal insulin receptor signaling in VSMCs, but does not affect PDGF-induced proliferative signaling. These findings suggest that systemic insulin resistance rather than VSMC-specific dysregulation of insulin receptor signaling by high fructose may play a major role in enhancing atherosclerosis and neointimal hyperplasia. Copyright © 2016 Elsevier B.V. All rights reserved.

  7. Oxidative and inflammatory signals in obesity-associated vascular abnormalities.

    Science.gov (United States)

    Reho, John J; Rahmouni, Kamal

    2017-07-15

    Obesity is associated with increased cardiovascular morbidity and mortality in part due to vascular abnormalities such as endothelial dysfunction and arterial stiffening. The hypertension and other health complications that arise from these vascular defects increase the risk of heart diseases and stroke. Prooxidant and proinflammatory signaling pathways as well as adipocyte-derived factors have emerged as critical mediators of obesity-associated vascular abnormalities. Designing treatments aimed specifically at improving the vascular dysfunction caused by obesity may provide an effective therapeutic approach to prevent the cardiovascular sequelae associated with excessive adiposity. In this review, we discuss the recent evidence supporting the role of oxidative stress and cytokines and inflammatory signals within the vasculature as well as the impact of the surrounding perivascular adipose tissue (PVAT) on the regulation of vascular function and arterial stiffening in obesity. In particular, we focus on the highly plastic nature of the vasculature in response to altered oxidant and inflammatory signaling and highlight how weight management can be an effective therapeutic approach to reduce the oxidative stress and inflammatory signaling and improve vascular function. © 2017 The Author(s). Published by Portland Press Limited on behalf of the Biochemical Society.

  8. Electrotonic vascular signal conduction and nephron synchronization

    DEFF Research Database (Denmark)

    Marsh, D.J.; Toma, I.; Sosnovtseva, Olga

    2009-01-01

    Marsh DJ, Toma I, Sosnovtseva OV, Peti-Peterdi J, Holstein-Rathlou NH. Electrotonic vascular signal conduction and nephron synchronization. Am J Physiol Renal Physiol 296: F751-F761, 2009. First published December 30, 2008; doi:10.1152/ajprenal.90669.2008.-Tubuloglomerular feedback (TGF) and the ......Marsh DJ, Toma I, Sosnovtseva OV, Peti-Peterdi J, Holstein-Rathlou NH. Electrotonic vascular signal conduction and nephron synchronization. Am J Physiol Renal Physiol 296: F751-F761, 2009. First published December 30, 2008; doi:10.1152/ajprenal.90669.2008.-Tubuloglomerular feedback (TGF......) and the myogenic mechanism control afferent arteriolar diameter in each nephron and regulate blood flow. Both mechanisms generate self-sustained oscillations, the oscillations interact, TGF modulates the frequency and amplitude of the myogenic oscillation, and the oscillations synchronize; a 5: 1 frequency ratio...... is the most frequent. TGF oscillations synchronize in nephron pairs supplied from a common cortical radial artery, as do myogenic oscillations. We propose that electrotonic vascular signal propagation from one juxtaglomerular apparatus interacts with similar signals from other nephrons to produce...

  9. Graph analysis of cell clusters forming vascular networks

    Science.gov (United States)

    Alves, A. P.; Mesquita, O. N.; Gómez-Gardeñes, J.; Agero, U.

    2018-03-01

    This manuscript describes the experimental observation of vasculogenesis in chick embryos by means of network analysis. The formation of the vascular network was observed in the area opaca of embryos from 40 to 55 h of development. In the area opaca endothelial cell clusters self-organize as a primitive and approximately regular network of capillaries. The process was observed by bright-field microscopy in control embryos and in embryos treated with Bevacizumab (Avastin), an antibody that inhibits the signalling of the vascular endothelial growth factor (VEGF). The sequence of images of the vascular growth were thresholded, and used to quantify the forming network in control and Avastin-treated embryos. This characterization is made by measuring vessels density, number of cell clusters and the largest cluster density. From the original images, the topology of the vascular network was extracted and characterized by means of the usual network metrics such as: the degree distribution, average clustering coefficient, average short path length and assortativity, among others. This analysis allows to monitor how the largest connected cluster of the vascular network evolves in time and provides with quantitative evidence of the disruptive effects that Avastin has on the tree structure of vascular networks.

  10. Cellular Architecture Regulates Collective Calcium Signaling and Cell Contractility.

    Directory of Open Access Journals (Sweden)

    Jian Sun

    2016-05-01

    Full Text Available A key feature of multicellular systems is the ability of cells to function collectively in response to external stimuli. However, the mechanisms of intercellular cell signaling and their functional implications in diverse vascular structures are poorly understood. Using a combination of computational modeling and plasma lithography micropatterning, we investigate the roles of structural arrangement of endothelial cells in collective calcium signaling and cell contractility. Under histamine stimulation, endothelial cells in self-assembled and microengineered networks, but not individual cells and monolayers, exhibit calcium oscillations. Micropatterning, pharmacological inhibition, and computational modeling reveal that the calcium oscillation depends on the number of neighboring cells coupled via gap junctional intercellular communication, providing a mechanistic basis of the architecture-dependent calcium signaling. Furthermore, the calcium oscillation attenuates the histamine-induced cytoskeletal reorganization and cell contraction, resulting in differential cell responses in an architecture-dependent manner. Taken together, our results suggest that endothelial cells can sense and respond to chemical stimuli according to the vascular architecture via collective calcium signaling.

  11. Gravity sensing and signal transduction in vascular plant primary roots.

    Science.gov (United States)

    Baldwin, Katherine L; Strohm, Allison K; Masson, Patrick H

    2013-01-01

    During gravitropism, the potential energy of gravity is converted into a biochemical signal. How this transfer occurs remains one of the most exciting mysteries in plant cell biology. New experiments are filling in pieces of the puzzle. In this review, we introduce gravitropism and give an overview of what we know about gravity sensing in roots of vascular plants, with special highlight on recent papers. When plant roots are reoriented sideways, amyloplast resedimentation in the columella cells is a key initial step in gravity sensing. This process somehow leads to cytoplasmic alkalinization of these cells followed by relocalization of auxin efflux carriers (PINs). This changes auxin flow throughout the root, generating a lateral gradient of auxin across the cap that upon transmission to the elongation zone leads to differential cell elongation and gravibending. We will present the evidence for and against the following players having a role in transferring the signal from the amyloplast sedimentation into the auxin signaling cascade: mechanosensitive ion channels, actin, calcium ions, inositol trisphosphate, receptors/ligands, ARG1/ARL2, spermine, and the TOC complex. We also outline auxin transport and signaling during gravitropism.

  12. Endothelial Mechanotransduction, Redox Signaling and the Regulation of Vascular Inflammatory Pathways

    Directory of Open Access Journals (Sweden)

    Shampa Chatterjee

    2018-06-01

    Full Text Available The endothelium that lines the interior of blood vessels is directly exposed to blood flow. The shear stress arising from blood flow is “sensed” by the endothelium and is “transduced” into biochemical signals that eventually control vascular tone and homeostasis. Sensing and transduction of physical forces occur via signaling processes whereby the forces associated with blood flow are “sensed” by a mechanotransduction machinery comprising of several endothelial cell elements. Endothelial “sensing” involves converting the physical cues into cellular signaling events such as altered membrane potential and activation of kinases, which are “transmission” signals that cause oxidant production. Oxidants produced are the “transducers” of the mechanical signals? What is the function of these oxidants/redox signals? Extensive data from various studies indicate that redox signals initiate inflammation signaling pathways which in turn can compromise vascular health. Thus, inflammation, a major response to infection or endotoxins, can also be initiated by the endothelium in response to various flow patterns ranging from aberrant flow to alteration of flow such as cessation or sudden increase in blood flow. Indeed, our work has shown that endothelial mechanotransduction signaling pathways participate in generation of redox signals that affect the oxidant and inflammation status of cells. Our goal in this review article is to summarize the endothelial mechanotransduction pathways that are activated with stop of blood flow and with aberrant flow patterns; in doing so we focus on the complex link between mechanical forces and inflammation on the endothelium. Since this “inflammation susceptible” phenotype is emerging as a trigger for pathologies ranging from atherosclerosis to rejection post-organ transplant, an understanding of the endothelial machinery that triggers these processes is very crucial and timely.

  13. Apelin-13 upregulates Egr-1 expression in rat vascular smooth muscle cells through the PI3K/Akt and PKC signaling pathways

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Qi-Feng [Department of Cardiology, The First Affiliated Hospital of Liaoning Medical University, Jinzhou 121001 (China); Yu, Hong-Wei [Department of Cardiology, Jinzhou Central Hospital, Jinzhou 121001 (China); Sun, Li-Li [Department of Ophthalmology, The Third Affiliated Hospital of Liaoning Medical University, Jinzhou 121001 (China); You, Lu; Tao, Gui-Zhou [Department of Cardiology, The First Affiliated Hospital of Liaoning Medical University, Jinzhou 121001 (China); Qu, Bao-Ze, E-mail: qubaoze1971@hotmail.com [Department of Cardiology, The First Affiliated Hospital of Liaoning Medical University, Jinzhou 121001 (China)

    2015-12-25

    Previous studies have shown that Apelin-13 upregulates early growth response factor-1 (Egr-1) via the extracellular signal-regulated protein kinase (ERK) signaling pathway. Apelin-13 induces proliferation and migration of vascular smooth muscle cells (VSMCs) as well as the upregulation of osteopontin (OPN) via the upregulation of Egr-1. This study was designed to further explore the activity of Apelin-13 in VSMCs by investigating members of the mitogen-activated protein kinase (MAPK) family, in particular Jun kinase (JNK) and p38 mitogen-activated protein kinase (P38). We also examined whether the phosphatidylinositol 3 kinase (PI3K)/protein kinase B (Akt) and protein kinase C (PKC) signaling pathways were involved in the regulation of Egr-1 by Apelin-13. We treated rat aortic VSMCs with Apelin-13 and examined the expression of JNK, p-JNK, P38, and p-P38 to investigate whether Apelin-13-mediated increases in Egr-1 occurred through the JNK and P38 signaling pathways. We then pretreated VSMCs with the Gi protein inhibitor pertussis toxin (PTX) and the Gq inhibitor YM254890, added Apelin-13 and looked for changes in Egr-1 expression. Finally, we pretreated with the PI3K inhibitor LY294002 and the PKC inhibitor GF109203X, and treated with Apelin-13. Our results showed that JNK and P38 did not participate in Apelin-13-mediated increase in Egr-1. Instead, Apelin-13 upregulation of Egr-1 was mediated by a PTX-sensitive Gi protein. Apelin-13 did increase ERK phosphorylation through the PI3K/Akt and PKC signaling pathways, resulting in changes in Egr-1 expression. These data provide important targets for future studies to modulate vascular remodeling. - Highlights: • Apelin-13 mediates Egr-1 upregulation in vascular smooth muscle cells via ERK1/2. • The underlying mechanisms are unknown, but exclude Jnk or p38 pathway activation. • Apelin-13 binds to Gi, activating the PI3K/Akt and PKC signaling cascades. • Consequent ERK phosphorylation results in increased Egr-1

  14. Apelin-13 upregulates Egr-1 expression in rat vascular smooth muscle cells through the PI3K/Akt and PKC signaling pathways

    International Nuclear Information System (INIS)

    Liu, Qi-Feng; Yu, Hong-Wei; Sun, Li-Li; You, Lu; Tao, Gui-Zhou; Qu, Bao-Ze

    2015-01-01

    Previous studies have shown that Apelin-13 upregulates early growth response factor-1 (Egr-1) via the extracellular signal-regulated protein kinase (ERK) signaling pathway. Apelin-13 induces proliferation and migration of vascular smooth muscle cells (VSMCs) as well as the upregulation of osteopontin (OPN) via the upregulation of Egr-1. This study was designed to further explore the activity of Apelin-13 in VSMCs by investigating members of the mitogen-activated protein kinase (MAPK) family, in particular Jun kinase (JNK) and p38 mitogen-activated protein kinase (P38). We also examined whether the phosphatidylinositol 3 kinase (PI3K)/protein kinase B (Akt) and protein kinase C (PKC) signaling pathways were involved in the regulation of Egr-1 by Apelin-13. We treated rat aortic VSMCs with Apelin-13 and examined the expression of JNK, p-JNK, P38, and p-P38 to investigate whether Apelin-13-mediated increases in Egr-1 occurred through the JNK and P38 signaling pathways. We then pretreated VSMCs with the Gi protein inhibitor pertussis toxin (PTX) and the Gq inhibitor YM254890, added Apelin-13 and looked for changes in Egr-1 expression. Finally, we pretreated with the PI3K inhibitor LY294002 and the PKC inhibitor GF109203X, and treated with Apelin-13. Our results showed that JNK and P38 did not participate in Apelin-13-mediated increase in Egr-1. Instead, Apelin-13 upregulation of Egr-1 was mediated by a PTX-sensitive Gi protein. Apelin-13 did increase ERK phosphorylation through the PI3K/Akt and PKC signaling pathways, resulting in changes in Egr-1 expression. These data provide important targets for future studies to modulate vascular remodeling. - Highlights: • Apelin-13 mediates Egr-1 upregulation in vascular smooth muscle cells via ERK1/2. • The underlying mechanisms are unknown, but exclude Jnk or p38 pathway activation. • Apelin-13 binds to Gi, activating the PI3K/Akt and PKC signaling cascades. • Consequent ERK phosphorylation results in increased Egr-1

  15. Nano- and microstructured materials for in vitro studies of the physiology of vascular cells

    Directory of Open Access Journals (Sweden)

    Alexandra M. Greiner

    2016-11-01

    Full Text Available The extracellular environment of vascular cells in vivo is complex in its chemical composition, physical properties, and architecture. Consequently, it has been a great challenge to study vascular cell responses in vitro, either to understand their interaction with their native environment or to investigate their interaction with artificial structures such as implant surfaces. New procedures and techniques from materials science to fabricate bio-scaffolds and surfaces have enabled novel studies of vascular cell responses under well-defined, controllable culture conditions. These advancements are paving the way for a deeper understanding of vascular cell biology and materials–cell interaction. Here, we review previous work focusing on the interaction of vascular smooth muscle cells (SMCs and endothelial cells (ECs with materials having micro- and nanostructured surfaces. We summarize fabrication techniques for surface topographies, materials, geometries, biochemical functionalization, and mechanical properties of such materials. Furthermore, various studies on vascular cell behavior and their biological responses to micro- and nanostructured surfaces are reviewed. Emphasis is given to studies of cell morphology and motility, cell proliferation, the cytoskeleton and cell-matrix adhesions, and signal transduction pathways of vascular cells. We finalize with a short outlook on potential interesting future studies.

  16. Endothelial and Smooth Muscle Cell Interaction via FoxM1 Signaling Mediates Vascular Remodeling and Pulmonary Hypertension.

    Science.gov (United States)

    Dai, Zhiyu; Zhu, Maggie M; Peng, Yi; Jin, Hua; Machireddy, Narsa; Qian, Zhijian; Zhang, Xianming; Zhao, You-Yang

    2018-04-17

    Angioproliferative vasculopathy is a hallmark of pulmonary arterial hypertension (PAH). However, little is known how endothelial cell (EC) and smooth muscle cell (SMC) crosstalk regulates the angioproliferative vascular remodeling. We aimed to investigate the role of EC and SMC interaction and underlying signaling pathways in PH development. SMC-specific Foxm1 or Cxcr4 knockout mice, EC-specific Foxm1 or Egln1 knockout mice, as well as EC-specific Egln1/Cxcl12 double knockout mice were used to assess the role of FoxM1 on SMC proliferation and PH. Lung tissues and cells from PAH patients were employed to validate clinical relevance. FoxM1 inhibitor Thiostrepton was used in Sugen 5416/hypoxia- and monocrotaline-challenged rats. FoxM1 expression was markedly upregulated in lungs and pulmonary arterial SMCs of idiopathic PAH patients and 4 discrete PH rodent models. Mice with SMC- (but not EC-) specific deletion of Foxm1 were protected from hypoxia- or Sugen 5416/hypoxia-induced PH. The upregulation of FoxM1 in SMCs induced by multiple EC-derived factors (PDGF-B, CXCL12, ET-1 and MIF) mediated SMC proliferation. Genetic deletion of endothelial Cxcl12 in Egln1Tie2Cre mice or loss of its cognate receptor Cxcr4 in SMCs in hypoxia-treated mice inhibited FoxM1 expression, SMC proliferation and PH. Accordingly, pharmacological inhibition of FoxM1 inhibited severe PH in both Sugen 5416/hypoxia and monocrotaline-challenged rats. Multiple factors derived from dysfunctional ECs induced FoxM1 expression in SMCs and activated FoxM1-dependent SMC proliferation which contributes to pulmonary vascular remodeling and PH. Thus, targeting FoxM1 signaling represents a novel strategy for treatment of IPAH.

  17. Integration of hormonal signaling networks and mobile microRNAs is required for vascular patterning in Arabidopsis roots

    KAUST Repository

    Muraro, D.

    2013-12-31

    As multicellular organisms grow, positional information is continually needed to regulate the pattern in which cells are arranged. In the Arabidopsis root, most cell types are organized in a radially symmetric pattern; however, a symmetry-breaking event generates bisymmetric auxin and cytokinin signaling domains in the stele. Bidirectional cross-talk between the stele and the surrounding tissues involving a mobile transcription factor, SHORT ROOT (SHR), and mobile microRNA species also determines vascular pattern, but it is currently unclear how these signals integrate. We use a multicellular model to determine a minimal set of components necessary for maintaining a stable vascular pattern. Simulations perturbing the signaling network show that, in addition to the mutually inhibitory interaction between auxin and cytokinin, signaling through SHR, microRNA165/6, and PHABULOSA is required to maintain a stable bisymmetric pattern. We have verified this prediction by observing loss of bisymmetry in shr mutants. The model reveals the importance of several features of the network, namely the mutual degradation of microRNA165/6 and PHABULOSA and the existence of an additional negative regulator of cytokinin signaling. These components form a plausible mechanism capable of patterning vascular tissues in the absence of positional inputs provided by the transport of hormones from the shoot.

  18. Integration of hormonal signaling networks and mobile microRNAs is required for vascular patterning in Arabidopsis roots

    KAUST Repository

    Muraro, D.; Mellor, N.; Pound, M. P.; Help, H.; Lucas, M.; Chopard, J.; Byrne, H. M.; Godin, C.; Hodgman, T. C.; King, J. R.; Pridmore, T. P.; Helariutta, Y.; Bennett, M. J.; Bishopp, A.

    2013-01-01

    As multicellular organisms grow, positional information is continually needed to regulate the pattern in which cells are arranged. In the Arabidopsis root, most cell types are organized in a radially symmetric pattern; however, a symmetry-breaking event generates bisymmetric auxin and cytokinin signaling domains in the stele. Bidirectional cross-talk between the stele and the surrounding tissues involving a mobile transcription factor, SHORT ROOT (SHR), and mobile microRNA species also determines vascular pattern, but it is currently unclear how these signals integrate. We use a multicellular model to determine a minimal set of components necessary for maintaining a stable vascular pattern. Simulations perturbing the signaling network show that, in addition to the mutually inhibitory interaction between auxin and cytokinin, signaling through SHR, microRNA165/6, and PHABULOSA is required to maintain a stable bisymmetric pattern. We have verified this prediction by observing loss of bisymmetry in shr mutants. The model reveals the importance of several features of the network, namely the mutual degradation of microRNA165/6 and PHABULOSA and the existence of an additional negative regulator of cytokinin signaling. These components form a plausible mechanism capable of patterning vascular tissues in the absence of positional inputs provided by the transport of hormones from the shoot.

  19. p115 RhoGEF activates the Rac1 GTPase signaling cascade in MCP1 chemokine-induced vascular smooth muscle cell migration and proliferation.

    Science.gov (United States)

    Singh, Nikhlesh K; Janjanam, Jagadeesh; Rao, Gadiparthi N

    2017-08-25

    Although the involvement of Rho proteins in the pathogenesis of vascular diseases is well studied, little is known about the role of their upstream regulators, the Rho guanine nucleotide exchange factors (RhoGEFs). Here, we sought to identify the RhoGEFs involved in monocyte chemotactic protein 1 (MCP1)-induced vascular wall remodeling. We found that, among the RhoGEFs tested, MCP1 induced tyrosine phosphorylation of p115 RhoGEF but not of PDZ RhoGEF or leukemia-associated RhoGEF in human aortic smooth muscle cells (HASMCs). Moreover, p115 RhoGEF inhibition suppressed MCP1-induced HASMC migration and proliferation. Consistent with these observations, balloon injury (BI) induced p115 RhoGEF tyrosine phosphorylation in rat common carotid arteries, and siRNA-mediated down-regulation of its levels substantially attenuated BI-induced smooth muscle cell migration and proliferation, resulting in reduced neointima formation. Furthermore, depletion of p115 RhoGEF levels also abrogated MCP1- or BI-induced Rac1-NFATc1-cyclin D1-CDK6-PKN1-CDK4-PAK1 signaling, which, as we reported previously, is involved in vascular wall remodeling. Our findings also show that protein kinase N1 (PKN1) downstream of Rac1-cyclin D1/CDK6 and upstream of CDK4-PAK1 in the p115 RhoGEF-Rac1-NFATc1-cyclin D1-CDK6-PKN1-CDK4-PAK1 signaling axis is involved in the modulation of vascular wall remodeling. Of note, we also observed that CCR2-G i/o -Fyn signaling mediates MCP1-induced p115 RhoGEF and Rac1 GTPase activation. These findings suggest that p115 RhoGEF is critical for MCP1-induced HASMC migration and proliferation in vitro and for injury-induced neointima formation in vivo by modulating Rac1-NFATc1-cyclin D1-CDK6-PKN1-CDK4-PAK1 signaling. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

  20. Stem development through vascular tissues: EPFL-ERECTA family signaling that bounces in and out of phloem.

    Science.gov (United States)

    Tameshige, Toshiaki; Ikematsu, Shuka; Torii, Keiko U; Uchida, Naoyuki

    2017-01-01

    Plant cells communicate with each other using a variety of signaling molecules. Recent studies have revealed that various types of secreted peptides, as well as phytohormones known since long ago, mediate cell-cell communication in diverse contexts of plant life. These peptides affect cellular activities, such as proliferation and cell fate decisions, through their perception by cell surface receptors located on the plasma membrane of target cells. ERECTA (ER), an Arabidopsis thaliana receptor kinase gene, was first identified as a stem growth regulator, and since then an increasing number of studies have shown that ER is involved in a wide range of developmental and physiological processes. In particular, molecular functions of ER have been extensively studied in stomatal patterning. Furthermore, the importance of ER signaling in vascular tissues of inflorescence stems, especially in phloem cells, has recently been highlighted. In this review article, first we briefly summarize the history of ER research including studies on stomatal development, then introduce ER functions in vascular tissues, and discuss its interactions with phytohormones and other receptor kinase signaling pathways. Future questions and challenges will also be addressed. © The Author 2016. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  1. Memo has a novel role in S1P signaling and is [corrected] crucial for vascular development.

    Science.gov (United States)

    Kondo, Shunya; Bottos, Alessia; Allegood, Jeremy C; Masson, Regis; Maurer, Francisca G; Genoud, Christel; Kaeser, Patrick; Huwiler, Andrea; Murakami, Masato; Spiegel, Sarah; Hynes, Nancy E

    2014-01-01

    Memo is a conserved protein that was identified as an essential mediator of tumor cell motility induced by receptor tyrosine kinase activation. Here we show that Memo null mouse embryonic fibroblasts (MEFs) are impaired in PDGF-induced migration and this is due to a defect in sphingosine-1-phosphate (S1P) signaling. S1P is a bioactive phospholipid produced in response to multiple stimuli, which regulates many cellular processes. S1P is secreted to the extracellular milieu where it exerts its function by binding a family of G-protein coupled receptors (S1PRs), causing their activation in an autocrine or paracrine manner. The process, termed cell-autonomous S1PR signaling, plays a role in survival and migration. Indeed, PDGF uses cell-autonomous S1PR signaling to promote cell migration; we show here that this S1P pathway requires Memo. Using vascular endothelial cells (HUVECs) with Memo knock-down we show that their survival in conditions of serum-starvation is impaired. Furthermore, Memo loss in HUVECs causes a reduction of junctional VE-cadherin and an increase in sprout formation. Each of these phenotypes is rescued by S1P or S1P agonist addition, showing that Memo also plays an important role in cell-autonomous S1PR signaling in endothelial cells. We also produced conventional and endothelial cell-specific conditional Memo knock-out mouse strains and show that Memo is essential for embryonic development. Starting at E13.5 embryos of both strains display bleeding and other vascular problems, some of the phenotypes that have been described in mouse strains lacking S1PRs. The essential role of Memo in embryonic vascular development may be due in part to alterations in S1P signaling. Taken together our results show that Memo has a novel role in the S1P pathway and that Memo is needed to promote cell-autonomous S1PR activation.

  2. Vascular Mural Cells Promote Noradrenergic Differentiation of Embryonic Sympathetic Neurons

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    Vitor Fortuna

    2015-06-01

    Full Text Available The sympathetic nervous system controls smooth muscle tone and heart rate in the cardiovascular system. Postganglionic sympathetic neurons (SNs develop in close proximity to the dorsal aorta (DA and innervate visceral smooth muscle targets. Here, we use the zebrafish embryo to ask whether the DA is required for SN development. We show that noradrenergic (NA differentiation of SN precursors temporally coincides with vascular mural cell (VMC recruitment to the DA and vascular maturation. Blocking vascular maturation inhibits VMC recruitment and blocks NA differentiation of SN precursors. Inhibition of platelet-derived growth factor receptor (PDGFR signaling prevents VMC differentiation and also blocks NA differentiation of SN precursors. NA differentiation is normal in cloche mutants that are devoid of endothelial cells but have VMCs. Thus, PDGFR-mediated mural cell recruitment mediates neurovascular interactions between the aorta and sympathetic precursors and promotes their noradrenergic differentiation.

  3. Sox17 drives functional engraftment of endothelium converted from non-vascular cells.

    Science.gov (United States)

    Schachterle, William; Badwe, Chaitanya R; Palikuqi, Brisa; Kunar, Balvir; Ginsberg, Michael; Lis, Raphael; Yokoyama, Masataka; Elemento, Olivier; Scandura, Joseph M; Rafii, Shahin

    2017-01-16

    Transplanting vascular endothelial cells (ECs) to support metabolism and express regenerative paracrine factors is a strategy to treat vasculopathies and to promote tissue regeneration. However, transplantation strategies have been challenging to develop, because ECs are difficult to culture and little is known about how to direct them to stably integrate into vasculature. Here we show that only amniotic cells could convert to cells that maintain EC gene expression. Even so, these converted cells perform sub-optimally in transplantation studies. Constitutive Akt signalling increases expression of EC morphogenesis genes, including Sox17, shifts the genomic targeting of Fli1 to favour nearby Sox consensus sites and enhances the vascular function of converted cells. Enforced expression of Sox17 increases expression of morphogenesis genes and promotes integration of transplanted converted cells into injured vessels. Thus, Ets transcription factors specify non-vascular, amniotic cells to EC-like cells, whereas Sox17 expression is required to confer EC function.

  4. Potential role of insulin signaling on vascular smooth muscle cell migration, proliferation, and inflammation pathways.

    Science.gov (United States)

    Cersosimo, Eugenio; Xu, Xiaojing; Musi, Nicolas

    2012-02-15

    To investigate the role of insulin signaling pathways in migration, proliferation, and inflammation of vascular smooth muscle cells (VSMCs), we examined the expression of active components of the phosphatidyl inositol 3 (PI-3) kinase (p-Akt) and mitogen-activated protein kinase (MAPK) (p-Erk) in primary cultures of VSMCs from human coronary arteries. VSMCs were treated in a dose-response manner with insulin (0, 1, 10, and 100 nM) for 20 min, and Akt and Erk phosphorylation were measured by Western blot analysis. In separate experiments, we evaluated the effect of 200 μM palmitate, in the presence and absence of 8 μM pioglitazone, on insulin-stimulated (100 nM for 20 min) Akt and Erk phosphorylation. The phosphorylation of Akt and Erk in VSMCs exhibited a dose dependency with a three- to fourfold increase, respectively, at the highest dose (100 nM). In the presence of palmitate, insulin-induced Akt phosphorylation was completely abolished, and there was a threefold increase in p-Erk. With addition of pioglitazone, the phosphorylation of Akt by insulin remained unchanged, whereas insulin-stimulated Erk phosphorylation was reduced by pioglitazone. These data in VSMCs indicate that high palmitate decreases insulin-stimulated Akt phosphorylation and stimulates MAPK, whereas preexposure peroxisome proliferator-activated receptor-γ agonist pioglitazone preserves Akt phosphorylation and simultaneously attenuates MAPK signaling. Our results suggest that metabolic and mitogenic insulin signals have different sensitivity, are independently regulated, and may play a role in arterial smooth muscle cells migration, proliferation, and inflammation in conditions of acute hyperinsulinemia.

  5. [Effect of microRNA-34a/SIRT1/p53 signal pathway on notoginsenoside R₁ delaying vascular endothelial cell senescence].

    Science.gov (United States)

    Lai, Xiao-Hua; Lei, Yan; Yang, Jing; Xiu, Cheng-Kui

    2018-02-01

    This study aimed to investigate the effect of notoginsenoside R₁ in delaying H₂O₂-induced vascular endothelial cell senescence through microRNA-34a/SIRT1/p53 signal pathway. In this study, human umbilical vein endothelial cells(HUVECs) were selected as the study object; the aging model induced by hydrogen peroxide(H₂O₂) was established, with resveratrol as the positive drug. HUVECs were randomly divided into four groups, youth group, senescence model group, notoginsenoside R₁ group and resveratrol group. Notoginsenoside R₁ group and resveratrol group were modeled with 100 μmoL·L⁻¹ H₂O₂ for 4 h after 24 h treatment with notoginsenoside R₁(30 μmoL·L⁻¹) and resveratrol(10 μmoL·L⁻¹) respectively. At the end, each group was cultured with complete medium for 24 h. The degree of cellular senescence was detected by senescence-associated β-galactosidase(SA-β-Gal) staining kit, the cell viability was detected by cell counting kit-8, the cell cycle distribution was analyzed by flow cytometry, and the cellular SOD activity was detected by WST-1 method in each group. The expressions of SIRT1, p53, p21 and p16 proteins in HUVECs were detected by Western blot. In addition, the mRNA expressions of miRNA-34a, SIRT1 and p53 in HUVECs were assayed by Real-time PCR. These results indicated that notoginsenoside R₁ significantly reduced the positive staining rate of senescent cells, enhanced the cell proliferation capacity and intracellular SOD activity, decreased the proportion of cells in G₀/G₁ phase, and increased the percentage of cells in S phase simultaneously compared with the senescence model group. Moreover, notoginsenoside R₁ decreased the mRNA expressions of miRNA-34a and p53 and the protein expression of p53, p21 and p16.At the same time, notoginsenoside R₁ increased the protein and mRNA expressions of SIRT1. The differences in these results between the senescence model group and the

  6. Vascular Mural Cells Promote Noradrenergic Differentiation of Embryonic Sympathetic Neurons.

    Science.gov (United States)

    Fortuna, Vitor; Pardanaud, Luc; Brunet, Isabelle; Ola, Roxana; Ristori, Emma; Santoro, Massimo M; Nicoli, Stefania; Eichmann, Anne

    2015-06-23

    The sympathetic nervous system controls smooth muscle tone and heart rate in the cardiovascular system. Postganglionic sympathetic neurons (SNs) develop in close proximity to the dorsal aorta (DA) and innervate visceral smooth muscle targets. Here, we use the zebrafish embryo to ask whether the DA is required for SN development. We show that noradrenergic (NA) differentiation of SN precursors temporally coincides with vascular mural cell (VMC) recruitment to the DA and vascular maturation. Blocking vascular maturation inhibits VMC recruitment and blocks NA differentiation of SN precursors. Inhibition of platelet-derived growth factor receptor (PDGFR) signaling prevents VMC differentiation and also blocks NA differentiation of SN precursors. NA differentiation is normal in cloche mutants that are devoid of endothelial cells but have VMCs. Thus, PDGFR-mediated mural cell recruitment mediates neurovascular interactions between the aorta and sympathetic precursors and promotes their noradrenergic differentiation. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

  7. Differentiation and Application of Induced Pluripotent Stem Cell-Derived Vascular Smooth Muscle Cells.

    Science.gov (United States)

    Maguire, Eithne Margaret; Xiao, Qingzhong; Xu, Qingbo

    2017-11-01

    Vascular smooth muscle cells (VSMCs) play a role in the development of vascular disease, for example, neointimal formation, arterial aneurysm, and Marfan syndrome caused by genetic mutations in VSMCs, but little is known about the mechanisms of the disease process. Advances in induced pluripotent stem cell technology have now made it possible to derive VSMCs from several different somatic cells using a selection of protocols. As such, researchers have set out to delineate key signaling processes involved in triggering VSMC gene expression to grasp the extent of gene regulatory networks involved in phenotype commitment. This technology has also paved the way for investigations into diseases affecting VSMC behavior and function, which may be treatable once an identifiable culprit molecule or gene has been repaired. Moreover, induced pluripotent stem cell-derived VSMCs are also being considered for their use in tissue-engineered blood vessels as they may prove more beneficial than using autologous vessels. Finally, while several issues remains to be clarified before induced pluripotent stem cell-derived VSMCs can become used in regenerative medicine, they do offer both clinicians and researchers hope for both treating and understanding vascular disease. In this review, we aim to update the recent progress on VSMC generation from stem cells and the underlying molecular mechanisms of VSMC differentiation. We will also explore how the use of induced pluripotent stem cell-derived VSMCs has changed the game for regenerative medicine by offering new therapeutic avenues to clinicians, as well as providing researchers with a new platform for modeling of vascular disease. © 2017 American Heart Association, Inc.

  8. Dipeptidyl peptidase-4 inhibitor gemigliptin protects against vascular calcification in an experimental chronic kidney disease and vascular smooth muscle cells.

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    Soon-Youn Choi

    Full Text Available Although dipeptidyl peptidase-4 inhibitors, a class of antidiabetic drugs, have various pleiotropic effects, it remains undetermined whether gemigliptin has a beneficial effect on vascular calcification. Therefore, this study was performed to evaluate the effect of gemigliptin on vascular calcification in a rat model of adenine-induced chronic kidney disease and in cultured vascular smooth muscle cells. Gemigliptin attenuated calcification of abdominal aorta and expression of RUNX2 in adenine-induced chronic kidney disease rats. In cultured vascular smooth muscle cells, phosphate-induced increase in calcium content was reduced by gemigliptin. Gemigliptin reduced phosphate-induced PiT-1 mRNA expression, reactive oxygen species generation, and NADPH oxidase mRNA expression (p22phox and NOX4. The reduction of oxidative stress by gemigliptin was associated with the downregulation of phospho-PI3K/AKT expression. High phosphate increased the expression of frizzled-3 (FDZ3 and decreased the expression of dickkopf-related protein-1 (DKK-1 in the Wnt pathway. These changes were attenuated by gemigliptin treatment. Gemigliptin restored the decreased expression of vascular smooth muscle cells markers (α-SMA and SM22α and increased expression of osteogenic makers (CBFA1, OSX, E11, and SOST induced by phosphate. In conclusion, gemigliptin attenuated vascular calcification and osteogenic trans-differentiation in vascular smooth muscle cells via multiple steps including downregulation of PiT-1 expression and suppression of reactive oxygen species generation, phospho-PI3K/AKT, and the Wnt signaling pathway.

  9. Luteolin Ameliorates Hypertensive Vascular Remodeling through Inhibiting the Proliferation and Migration of Vascular Smooth Muscle Cells

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    Jie Su

    2015-01-01

    Full Text Available Objectives. Preliminary researches showed that luteolin was used to treat hypertension. However, it is still unclear whether luteolin has effect on the hypertensive complication such as vascular remodeling. The present study was designed to investigate the effect of luteolin on the hypertensive vascular remodeling and its molecular mechanism. Method and Results. We evaluated the effect of luteolin on aorta thickening of hypertension in spontaneous hypertensive rats (SHRs and found that luteolin could significantly decrease the blood pressure and media thickness of aorta in vivo. Luteolin could inhibit angiotensin II- (Ang II- induced proliferation and migration of vascular smooth muscle cells (VSMCs. Dichlorofluorescein diacetate (DCFH-DA staining result showed that luteolin reduced Ang II-stimulated ROS production in VSMCs. Furthermore, western blot and gelatin zymography results showed that luteolin treatment leaded to a decrease in ERK1/2, p-ERK1/2, p-p38, MMP2, and proliferating cell nuclear antigen (PCNA protein level. Conclusion. These data support that luteolin can ameliorate hypertensive vascular remodeling by inhibiting the proliferation and migration of Ang II-induced VSMCs. Its mechanism is mediated by the regulation of MAPK signaling pathway and the production of ROS.

  10. In Vivo FRET Imaging of Tumor Endothelial Cells Highlights a Role of Low PKA Activity in Vascular Hyperpermeability.

    Science.gov (United States)

    Yamauchi, Fumio; Kamioka, Yuji; Yano, Tetsuya; Matsuda, Michiyuki

    2016-09-15

    Vascular hyperpermeability is a pathological hallmark of cancer. Previous in vitro studies have elucidated roles of various signaling molecules in vascular hyperpermeability; however, the activities of such signaling molecules have not been examined in live tumor tissues for technical reasons. Here, by in vivo two-photon excitation microscopy with transgenic mice expressing biosensors based on Förster resonance energy transfer, we examined the activity of protein kinase A (PKA), which maintains endothelial barrier function. The level of PKA activity was significantly lower in the intratumoral endothelial cells than the subcutaneous endothelial cells. PKA activation with a cAMP analogue alleviated the tumor vascular hyperpermeability, suggesting that the low PKA activity in the endothelial cells may be responsible for the tumor-tissue hyperpermeability. Because the vascular endothelial growth factor (VEGF) receptor is a canonical inducer of vascular hyperpermeability and a molecular target of anticancer drugs, we examined the causality between VEGF receptor activity and the PKA activity. Motesanib, a kinase inhibitor for VEGF receptor, activated tumor endothelial PKA and reduced the vascular permeability in the tumor. Conversely, subcutaneous injection of VEGF decreased endothelial PKA activity and induced hyperpermeability of subcutaneous blood vessels. Notably, in cultured human umbilical vascular endothelial cells, VEGF activated PKA rather than decreasing its activity, highlighting the remarkable difference between its actions in vitro and in vivo These data suggested that the VEGF receptor signaling pathway increases vascular permeability, at least in part, by reducing endothelial PKA activity in the live tumor tissue. Cancer Res; 76(18); 5266-76. ©2016 AACR. ©2016 American Association for Cancer Research.

  11. Vascular inflammatory cells in hypertension

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    David G. Harrison

    2012-05-01

    Full Text Available Hypertension is a common disorder with uncertain etiology. In the last several years, it has become evident that components of both the innate and adaptive immune system play an essential role in hypertension. Macrophages and T cells accumulate in the perivascular fat, the heart and the kidney of hypertensive patients and in animals with experimental hypertension. Various immunosuppressive agents lower blood pressure and prevent end-organ damage. Mice lacking lymphocytes are protected against hypertension, and adoptive transfer of T cells, but not B cells in the animals restores their blood pressure response to stimuli such as angiotensin II or high salt. Recent studies have shown that mice lacking macrophages have blunted hypertension in response to angiotensin II and that genetic deletion of macrophages markedly reduces experimental hypertension. Dendritic cells have also been implicated in this disease. Many hypertensive stimuli have triggering effects on the central nervous system and signals arising from the circumventricular organ seem to promote inflammation. Studies have suggested that central signals activate macrophages and T cells, which home to the kidney and vasculature and release cytokines, including IL-6 and IL-17, which in turn cause renal and vascular dysfunction and lead to blood pressure elevation. These recent discoveries provide a new understanding of hypertension and provide novel therapeutic opportunities for treatment of this serious disease.

  12. BMP-2 Overexpression Augments Vascular Smooth Muscle Cell Motility by Upregulating Myosin Va via Erk Signaling

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    Ming Zhang

    2014-01-01

    Full Text Available Background. The disruption of physiologic vascular smooth muscle cell (VSMC migration initiates atherosclerosis development. The biochemical mechanisms leading to dysfunctional VSMC motility remain unknown. Recently, cytokine BMP-2 has been implicated in various vascular physiologic and pathologic processes. However, whether BMP-2 has any effect upon VSMC motility, or by what manner, has never been investigated. Methods. VSMCs were adenovirally transfected to genetically overexpress BMP-2. VSMC motility was detected by modified Boyden chamber assay, confocal time-lapse video assay, and a colony wounding assay. Gene chip array and RT-PCR were employed to identify genes potentially regulated by BMP-2. Western blot and real-time PCR detected the expression of myosin Va and the phosphorylation of extracellular signal-regulated kinases 1/2 (Erk1/2. Immunofluorescence analysis revealed myosin Va expression locale. Intracellular Ca2+ oscillations were recorded. Results. VSMC migration was augmented in VSMCs overexpressing BMP-2 in a dose-dependent manner. siRNA-mediated knockdown of myosin Va inhibited VSMC motility. Both myosin Va mRNA and protein expression significantly increased after BMP-2 administration and were inhibited by Erk1/2 inhibitor U0126. BMP-2 induced Ca2+ oscillations, generated largely by a “cytosolic oscillator”. Conclusion. BMP-2 significantly increased VSMCs migration and myosin Va expression, via the Erk signaling pathway and intracellular Ca2+ oscillations. We provide additional insight into the pathophysiology of atherosclerosis, and inhibition of BMP-2-induced myosin Va expression may represent a potential therapeutic strategy.

  13. Progenitor cells in pulmonary vascular remodeling

    Science.gov (United States)

    Yeager, Michael E.; Frid, Maria G.; Stenmark, Kurt R.

    2011-01-01

    Pulmonary hypertension is characterized by cellular and structural changes in the walls of pulmonary arteries. Intimal thickening and fibrosis, medial hypertrophy and fibroproliferative changes in the adventitia are commonly observed, as is the extension of smooth muscle into the previously non-muscularized vessels. A majority of these changes are associated with the enhanced presence of α-SM-actin+ cells and inflammatory cells. Atypical abundances of functionally distinct endothelial cells, particularly in the intima (plexiform lesions), and also in the perivascular regions, are also described. At present, neither the origin(s) of these cells nor the molecular mechanisms responsible for their accumulation, in any of the three compartments of the vessel wall, have been fully elucidated. The possibility that they arise from either resident vascular progenitors or bone marrow–derived progenitor cells is now well established. Resident vascular progenitor cells have been demonstrated to exist within the vessel wall, and in response to certain stimuli, to expand and express myofibroblastic, endothelial or even hematopoietic markers. Bone marrow–derived or circulating progenitor cells have also been shown to be recruited to sites of vascular injury and to assume both endothelial and SM-like phenotypes. Here, we review the data supporting the contributory role of vascular progenitors (including endothelial progenitor cells, smooth muscle progenitor cells, pericytes, and fibrocytes) in vascular remodeling. A more complete understanding of the processes by which progenitor cells modulate pulmonary vascular remodeling will undoubtedly herald a renaissance of therapies extending beyond the control of vascular tonicity and reduction of pulmonary artery pressure. PMID:22034593

  14. Inhibition of Extracellular Signal-Regulated Kinases Ameliorates Hypertension-Induced Renal Vascular Remodeling in Rat Models

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    Li Jing

    2011-11-01

    Full Text Available The aim of this study is to investigate the effect of the extracellular signal-regulated kinases 1/2 (ERK1/2 inhibitor, PD98059, on high blood pressure and related vascular changes. Blood pressure was recorded, thicknesses of renal small artery walls were measured and ERK1/2 immunoreactivity and erk2 mRNA in renal vascular smooth muscle cells (VSMCs and endothelial cells were detected by immunohistochemistry and in situ hybridization in normotensive wistar kyoto (WKY rats, spontaneously hypertensive rats (SHR and PD98059-treated SHR. Compared with normo-tensive WKY rats, SHR developed hypertension at 8 weeks of age, thickened renal small artery wall and asymmetric arrangement of VSMCs at 16 and 24 weeks of age. Phospho-ERK1/2 immunoreactivity and erk2 mRNA expression levels were increased in VSMCs and endothelial cells of the renal small arteries in the SHR. Treating SHR with PD98059 reduced the spontaneous hypertension-induced vascular wall thickening. This effect was associated with suppressions of erk2 mRNA expression and ERK1/2 phosphorylation in VSMCs and endothelial cells of the renal small arteries. It is concluded that inhibition of ERK1/2 ameliorates hypertension induced vascular remodeling in renal small arteries.

  15. Nitric oxide signaling pathway regulates potassium chloride cotransporter-1 mRNA expression in vascular smooth muscle cells.

    Science.gov (United States)

    Di Fulvio, M; Lauf, P K; Adragna, N C

    2001-11-30

    Rat vascular smooth muscle cells (VSMCs) express at least two mRNAs for K-Cl cotransporters (KCC): KCC1 and KCC3. cGMP-dependent protein kinase I regulates KCC3 mRNA expression in these cells. Here, we show evidence implicating the nitric oxide (NO)/cGMP signaling pathway in the expression of KCC1 mRNA, considered to be the major cell volume regulator. VSMCs, expressing soluble guanylyl cyclase (sGC) and PKG-I isoforms showed a time- and concentration-dependent increase in KCC1 mRNA levels after treatment with sodium nitroprusside as demonstrated by semiquantitative RT-PCR. sGC-dependent regulation of KCC1 mRNA expression was confirmed using YC-1, a NO-independent sGC stimulator. The sGC inhibitor LY83583 blocked the effects of sodium nitroprusside and YC-1. Moreover, 8-Br-cGMP increased KCC1 mRNA expression in a concentration- and time-dependent fashion. The 8-Br-cGMP effect was partially blocked by KT5823 but not by actinomycin D. However, actinomycin D and cycloheximide increased basal KCC1 mRNA in an additive manner, suggesting different mechanisms of action for both drugs. These findings suggest that in VSMCs, the NO/cGMP-signaling pathway participates in KCC1 mRNA regulation at the post-transcriptional level.

  16. Oscillation of Angiogenesis and Vascular Dropout in Progressive Human Vascular Disease. [Vascular Pattern as Useful Read-Out of Complex Molecular Signaling

    Science.gov (United States)

    Parsons-Wingerter, Patricia

    2010-01-01

    When analyzed by VESsel GENeration Analysis (VESGEN) software, vascular patterns provide useful integrative read-outs of complex, interacting molecular signaling pathways. Using VESGEN, we recently discovered and published our innovative, surprising findings that angiogenesis oscillated with vascular dropout throughout progression of diabetic retinopathy, a blinding vascular disease. Our findings provide a potential paradigm shift in the current prevailing view on progression and treatment of this disease, and a new early-stage window of regenerative therapeutic opportunities. The findings also suggest that angiogenesis may oscillate with vascular disease in a homeostatic-like manner during early stages of other inflammatory progressive diseases such as cancer and coronary vascular disease.

  17. Vascular pattern formation in plants.

    Science.gov (United States)

    Scarpella, Enrico; Helariutta, Ykä

    2010-01-01

    Reticulate tissue systems exist in most multicellular organisms, and the principles underlying the formation of cellular networks have fascinated philosophers, mathematicians, and biologists for centuries. In particular, the beautiful and varied arrangements of vascular tissues in plants have intrigued mankind since antiquity, yet the organizing signals have remained elusive. Plant vascular tissues form systems of interconnected cell files throughout the plant body. Vascular cells are aligned with one another along continuous lines, and vascular tissues differentiate at reproducible positions within organ environments. However, neither the precise path of vascular differentiation nor the exact geometry of vascular networks is fixed or immutable. Several recent advances converge to reconcile the seemingly conflicting predictability and plasticity of vascular tissue patterns. A control mechanism in which an apical-basal flow of signal establishes a basic coordinate system for body axis formation and vascular strand differentiation, and in which a superimposed level of radial organizing cues elaborates cell patterns, would generate a reproducible tissue configuration in the context of an underlying robust, self-organizing structure, and account for the simultaneous regularity and flexibility of vascular tissue patterns. Copyright 2010 Elsevier Inc. All rights reserved.

  18. Combined strategy of endothelial cells coating, Sertoli cells coculture and infusion improves vascularization and rejection protection of islet graft.

    Directory of Open Access Journals (Sweden)

    Yang Li

    Full Text Available Improving islet graft revascularization and inhibiting rejection become crucial tasks for prolonging islet graft survival. Endothelial cells (ECs are the basis of islet vascularization and Sertoli cells (SCs have the talent to provide nutritional support and exert immunosuppressive effects. We construct a combined strategy of ECs coating in the presence of nutritious and immune factors supplied by SCs in a co-culture system to investigate the effect of vascularization and rejection inhibition for islet graft. In vivo, the combined strategy improved the survival and vascularization as well as inhibited lymphocytes and inflammatory cytokines. In vitro, we found the combinatorial strategy improved the function of islets and the effect of ECs-coating on islets. Combined strategy treated islets revealed higher levels of anti-apoptotic signal molecules (Bcl-2 and HSP-32, survival and function related molecules (PDX-1, Ki-67, ERK1/2 and Akt and demonstrated increased vascular endothelial growth factor receptor 2 (KDR and angiogenesis signal molecules (FAk and PLC-γ. SCs effectively inhibited the activation of lymphocyte stimulated by islets and ECs. Predominantly immunosuppressive cytokines could be detected in culture supernatants of the SCs coculture group. These results suggest that ECs-coating and Sertoli cells co-culture or infusion synergistically enhance islet survival and function after transplantation.

  19. Calcium dynamics in vascular smooth muscle

    OpenAIRE

    Amberg, Gregory C.; Navedo, Manuel F.

    2013-01-01

    Smooth muscle cells are ultimately responsible for determining vascular luminal diameter and blood flow. Dynamic changes in intracellular calcium are a critical mechanism regulating vascular smooth muscle contractility. Processes influencing intracellular calcium are therefore important regulators of vascular function with physiological and pathophysiological consequences. In this review we discuss the major dynamic calcium signals identified and characterized in vascular smooth muscle cells....

  20. Breast cancer drugs dampen vascular functions by interfering with nitric oxide signaling in endothelium

    International Nuclear Information System (INIS)

    Gajalakshmi, Palanivel; Priya, Mani Krishna; Pradeep, Thangaraj; Behera, Jyotirmaya; Muthumani, Kandasamy; Madhuwanti, Srinivasan; Saran, Uttara; Chatterjee, Suvro

    2013-01-01

    Widely used chemotherapeutic breast cancer drugs such as Tamoxifen citrate (TC), Capecitabine (CP) and Epirubicin (EP) are known to cause various cardiovascular side-effects among long term cancer survivors. Vascular modulation warrants nitric oxide (NO) signal transduction, which targets the vascular endothelium. We hypothesize that TC, CP and EP interference with the nitric oxide downstream signaling specifically, could lead to cardiovascular dysfunctions. The results demonstrate that while all three drugs attenuate NO and cyclic guanosine mono-phosphate (cGMP) production in endothelial cells, they caused elevated levels of NO in the plasma and RBC. However, PBMC and platelets did not show any significant changes under treatment. This implies that the drug effects are specific to the endothelium. Altered eNOS and phosphorylated eNOS (Ser-1177) localization patterns in endothelial cells were observed following drug treatments. Similarly, the expression of phosphorylated eNOS (Ser-1177) protein was decreased under the treatment of drugs. Altered actin polymerization was also observed following drug treatment, while addition of SpNO and 8Br-cGMP reversed this effect. Incubation with the drugs decreased endothelial cell migration whereas addition of YC-1, SC and 8Br-cGMP recovered the effect. Additionally molecular docking studies showed that all three drugs exhibited a strong binding affinity with the catalytic domain of human sGC. In conclusion, results indicate that TC, CP and EP cause endothelial dysfunctions via the NO–sGC–cGMP pathway and these effects could be recovered using pharmaceutical agonists of NO signaling pathway. Further, the study proposes a combination therapy of chemotherapeutic drugs and cGMP analogs, which would confer protection against chemotherapy mediated vascular dysfunctions in cancer patients. - Highlights: • NO production is reduced in endothelial cells under breast cancer drug treatment. • Cellular cGMP level is decreased under

  1. Breast cancer drugs dampen vascular functions by interfering with nitric oxide signaling in endothelium

    Energy Technology Data Exchange (ETDEWEB)

    Gajalakshmi, Palanivel; Priya, Mani Krishna; Pradeep, Thangaraj; Behera, Jyotirmaya; Muthumani, Kandasamy; Madhuwanti, Srinivasan; Saran, Uttara; Chatterjee, Suvro, E-mail: soovro@yahoo.ca

    2013-06-01

    Widely used chemotherapeutic breast cancer drugs such as Tamoxifen citrate (TC), Capecitabine (CP) and Epirubicin (EP) are known to cause various cardiovascular side-effects among long term cancer survivors. Vascular modulation warrants nitric oxide (NO) signal transduction, which targets the vascular endothelium. We hypothesize that TC, CP and EP interference with the nitric oxide downstream signaling specifically, could lead to cardiovascular dysfunctions. The results demonstrate that while all three drugs attenuate NO and cyclic guanosine mono-phosphate (cGMP) production in endothelial cells, they caused elevated levels of NO in the plasma and RBC. However, PBMC and platelets did not show any significant changes under treatment. This implies that the drug effects are specific to the endothelium. Altered eNOS and phosphorylated eNOS (Ser-1177) localization patterns in endothelial cells were observed following drug treatments. Similarly, the expression of phosphorylated eNOS (Ser-1177) protein was decreased under the treatment of drugs. Altered actin polymerization was also observed following drug treatment, while addition of SpNO and 8Br-cGMP reversed this effect. Incubation with the drugs decreased endothelial cell migration whereas addition of YC-1, SC and 8Br-cGMP recovered the effect. Additionally molecular docking studies showed that all three drugs exhibited a strong binding affinity with the catalytic domain of human sGC. In conclusion, results indicate that TC, CP and EP cause endothelial dysfunctions via the NO–sGC–cGMP pathway and these effects could be recovered using pharmaceutical agonists of NO signaling pathway. Further, the study proposes a combination therapy of chemotherapeutic drugs and cGMP analogs, which would confer protection against chemotherapy mediated vascular dysfunctions in cancer patients. - Highlights: • NO production is reduced in endothelial cells under breast cancer drug treatment. • Cellular cGMP level is decreased under

  2. VEGFR-3 signaling is regulated by a G-protein activator, activator of G-protein signaling 8, in lymphatic endothelial cells.

    Science.gov (United States)

    Sakima, Miho; Hayashi, Hisaki; Mamun, Abdullah Al; Sato, Motohiko

    2018-07-01

    Vascular endothelial growth factor C (VEGFC) and its cognate receptor VEGFR-3 play a key role in lymphangiogenesis. We previously reported that an ischemia-inducible Gβγ signal regulator, activator of G-protein signaling 8 (AGS8), regulated the subcellular distribution of vascular endothelial growth factor receptor-2 (VEGFR-2) and influenced VEGFA-induced signaling in vascular endothelial cells. Here, we report that AGS8 regulates VEGFR-3, which is another subtype of the VEGF receptor family, and mediates VEGFC signaling in human dermal lymphatic endothelial cells (HDLECs). VEGFC stimulated the proliferation of HDLECs and tube formation by HDLECs, which were inhibited by knocking down AGS8 by small interfering RNA (siRNA). AGS8 siRNA inhibited VEGFC-mediated phosphorylation of VEGFR-3 and its downstream molecules, including ERK1/2 and AKT. Analysis of fluorescence-activated cell sorting and immunofluorescence staining demonstrated that AGS8 knockdown was associated with a reduction of VEGFR-3 at the cell surface. Endocytosis inhibitors did not rescue the decrease of cell-surface VEGFR-3, suggesting that AGS8 regulated the trafficking of VEGFR-3 to the plasma membrane. An immunoprecipitation assay indicated that VEGFR-3 formed a complex including AGS8 and Gβγ in cells. These data suggest the novel regulation of VEGFC-VEGFR-3 by AGS8 in HDLECs and a potential role for AGS8 in lymphangiogenesis. Copyright © 2018 Elsevier Inc. All rights reserved.

  3. Vitisin B, a resveratrol tetramer, inhibits migration through inhibition of PDGF signaling and enhancement of cell adhesiveness in cultured vascular smooth muscle cells

    International Nuclear Information System (INIS)

    Ong, Eng-Thaim; Hwang, Tsong-Long; Huang, Yu-Ling; Lin, Chwan-Fwu; Wu, Wen-Bin

    2011-01-01

    Vascular smooth muscle cells (VSMCs) play an important role in normal vessel formation and in the development and progression of cardiovascular diseases. Grape plants contain resveratrol monomer and oligomers and drinking of wine made from grape has been linked to 'French Paradox'. In this study we evaluated the effect of vitisin B, a resveratrol tetramer, on VSMC behaviors. Vitisin B inhibited basal and PDGF-induced VSMC migration. Strikingly, it did not inhibit VSMC proliferation but inversely enhanced cell cycle progression and proliferation. Among the tested resveratrol oligomers, vitisin B showed an excellent inhibitory activity and selectivity on PDGF signaling. The anti-migratory effect by vitisin B was due to direct inhibition on PDGF signaling but was independent of interference with PDGF binding to VSMCs. Moreover, the enhanced VSMC adhesiveness to matrix contributed to the anti-migratory effect by vitisin B. Fluorescence microscopy revealed an enhanced reorganization of actin cytoskeleton and redistribution of activated focal adhesion proteins from cytosol to the peripheral edge of the cell membrane. This was confirmed by the observation that enhanced adhesiveness was repressed by the Src inhibitor. Finally, among the effects elicited by vitisin B, only the inhibitory effect toward basal migration was partially through estrogen receptor activation. We have demonstrated here that a resveratrol tetramer exhibited dual but opposite actions on VSMCs, one is to inhibit VSMC migration and the other is to promote VSMC proliferation. The anti-migratory effect was through a potent inhibition on PDGF signaling and novel enhancement on cell adhesion. - Highlights: → Several resveratrol oligomers from grape plants are examined on VSMC behaviors. → Tetraoligomer vitisin B shows excellent inhibitory activity and selectivity. → It exerts dual but opposing actions: anti-migratory and pro-proliferative effects. → The anti-migratory effect results from anti

  4. Ionizing radiation activates vascular endothelial growth factor-A transcription in human umbilical vein endothelial cells

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Hyounji; Kim, Kwang Seok; Jeong, Jae Hoon; Lim, Young Bin [Radiation Cancer Biology Team, Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of)

    2016-12-15

    Vascular endothelial growth factor (VEGF) is an essential paracrine factor for developmental and pathological angiogenesis. VEGF also exerts its effects in an autocrine manner in VEGF-producing cells. For instance, autocrine VEGF signaling occurs in tumor cells and contributes to key aspects of tumorigenesis, such as in the function of cancer stem cells and tumor initiation, which are independent of angiogenesis. In addition to tumors cells, non-transformed cells also express VEGF. For example, a VEGF dependent intracellular autocrine mechanism is crucial for the survival of hematopoietic stem cells and hematopoiesis. Stereotactic body radiation therapy (SBRT) is a novel treatment modality for early primary cancer and oligometastatic disease. SBRT delivers high-dose hypofractionated radiation, such as 20-60 Gy, to tumors in a single fraction or 2-5 fractions. As VEGF is a critical regulator of functional integrity and viability of vascular endothelial cells, we examined whether high-dose irradiation alters VEGF signaling by measuring the expression levels of VEGFA transcript. It is generally believed that endothelial cells do not produce VEGF in response to radiation. In present study, however, we provide the first demonstration of transcriptional regulation of VEGFA in human vascular endothelial cells by IR treatment. Irradiation with doses higher than 10 Gy in a single exposure triggers up-regulation of VEGFA transcription within 2 hours in HUVECs, whereas irradiation with 10 Gy does not alter VEGFA levels. Our data have shown that high-dose irradiation triggers immediate transactivation of VEGFA in human vascular endothelial cells.

  5. VEGF production and signaling in Müller glia are critical to modulating vascular function and neuronal integrity in diabetic retinopathy and hypoxic retinal vascular diseases.

    Science.gov (United States)

    Le, Yun-Zheng

    2017-10-01

    Müller glia (MG) are major retinal supporting cells that participate in retinal metabolism, function, maintenance, and protection. During the pathogenesis of diabetic retinopathy (DR), a neurovascular disease and a leading cause of blindness, MG modulate vascular function and neuronal integrity by regulating the production of angiogenic and trophic factors. In this article, I will (1) briefly summarize our work on delineating the role and mechanism of MG-modulated vascular function through the production of vascular endothelial growth factor (VEGF) and on investigating VEGF signaling-mediated MG viability and neural protection in diabetic animal models, (2) explore the relationship among VEGF and neurotrophins in protecting Müller cells in in vitro models of diabetes and hypoxia and its potential implication to neuroprotection in DR and hypoxic retinal diseases, and (3) discuss the relevance of our work to the effectiveness and safety of long-term anti-VEGF therapies, a widely used strategy to combat DR, diabetic macular edema, neovascular age-related macular degeneration, retinopathy of prematurity, and other hypoxic retinal vascular disorders. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. LRP1 functions as an atheroprotective integrator of TGFbeta and PDFG signals in the vascular wall: implications for Marfan syndrome.

    Directory of Open Access Journals (Sweden)

    Philippe Boucher

    2007-05-01

    Full Text Available The multifunctional receptor LRP1 controls expression, activity and trafficking of the PDGF receptor-beta in vascular smooth muscle cells (VSMC. LRP1 is also a receptor for TGFbeta1 and is required for TGFbeta mediated inhibition of cell proliferation.We show that loss of LRP1 in VSMC (smLRP(- in vivo results in a Marfan-like syndrome with nuclear accumulation of phosphorylated Smad2/3, disruption of elastic layers, tortuous aorta, and increased expression of the TGFbeta target genes thrombospondin-1 (TSP1 and PDGFRbeta in the vascular wall. Treatment of smLRP1(- animals with the PPARgamma agonist rosiglitazone abolished nuclear pSmad accumulation, reversed the Marfan-like phenotype, and markedly reduced smooth muscle proliferation, fibrosis and atherosclerosis independent of plasma cholesterol levels.Our findings are consistent with an activation of TGFbeta signals in the LRP1-deficient vascular wall. LRP1 may function as an integrator of proliferative and anti-proliferative signals that control physiological mechanisms common to the pathogenesis of Marfan syndrome and atherosclerosis, and this is essential for maintaining vascular wall integrity.

  7. Identification of cyst nematode B-type CLE peptides and modulation of the vascular stem cell pathway for feeding cell formation

    Science.gov (United States)

    Stem cells are important in the continuous formation of various tissues during postembryonic organogenesis. Stem cell pools in the SAM (shoot apical meristem), RAM (root apical meristem) and vascular procambium/cambium are regulated by CLE-receptor kinase-WOX signaling modules. Previous data showed ...

  8. RhoA/ROCK signaling regulates smooth muscle phenotypic modulation and vascular remodeling via the JNK pathway and vimentin cytoskeleton.

    Science.gov (United States)

    Tang, Lian; Dai, Fan; Liu, Yan; Yu, Xiaoqiang; Huang, Chao; Wang, Yuqin; Yao, Wenjuan

    2018-05-20

    The RhoA/ROCK signaling pathway regulates cell morphology, adhesion, proliferation, and migration. In this study, we investigated the regulatory role of RhoA/ROCK signaling on PDGF-BB-mediated smooth muscle phenotypic modulation and vascular remodeling and clarified the molecular mechanisms behind these effects. PDGF-BB treatment induced the activation of RhoA, ROCK, PDGF-Rβ, and the expression of PDGF-Rβ in HA-VSMCs (human aortic vascular smooth muscle cells). PDGF-Rβ inhibition and RhoA suppression blocked PDGF-BB-induced RhoA activation and ROCK induction. In addition, PDGF-BB-mediated cell proliferation and migration were suppressed by PDGF-Rβ inhibition, RhoA suppression, and ROCK inhibition, suggesting that PDGF-BB promotes phenotypic modulation of HA-VSMCs by activating the RhoA/ROCK pathway via the PDGF receptor. Moreover, suppressing both ROCK1 and ROCK2 blocked cell cycle progression from G0/G1 to S phase by decreasing the transcription and protein expression of cyclin D1, CDK2, and CDK4 via JNK/c-Jun pathway, thus reducing cell proliferation in PDGF-BB-treated HA-VSMCs. ROCK1 deletion, rather than ROCK2 suppression, significantly inhibited PDGF-BB-induced migration by reducing the expression of vimentin and preventing the remodeling of vimentin and phospho-vimentin. Furthermore, ROCK1 deletion suppressed vimentin by inhibiting the phosphorylation of Smad2/3 and the nuclear translocation of Smad4. These findings suggested that ROCK1 and ROCK2 might play different roles in PDGF-BB-mediated cell proliferation and migration in HA-VSMCs. In addition, PDGF-BB and its receptor participated in neointima formation and vascular remodeling by promoting cell cycle protein expression via the JNK pathway and enhancing vimentin expression in a rat balloon injury model; effects that were inhibited by treatment with fasudil. Together, the results of this study reveal a novel mechanism through which RhoA/ROCK signaling regulates smooth muscle phenotypic modulation and

  9. Signaling hierarchy regulating human endothelial cell development.

    Science.gov (United States)

    Kelly, Melissa A; Hirschi, Karen K

    2009-05-01

    Our present knowledge of the regulation of mammalian endothelial cell differentiation has been largely derived from studies of mouse embryonic development. However, unique mechanisms and hierarchy of signals that govern human endothelial cell development are unknown and, thus, explored in these studies. Using human embryonic stem cells as a model system, we were able to reproducibly and robustly generate differentiated endothelial cells via coculture on OP9 marrow stromal cells. We found that, in contrast to studies in the mouse, bFGF and VEGF had no specific effects on the initiation of human vasculogenesis. However, exogenous Ihh promoted endothelial cell differentiation, as evidenced by increased production of cells with cobblestone morphology that coexpress multiple endothelial-specific genes and proteins, form lumens, and exhibit DiI-AcLDL uptake. Inhibition of BMP signaling using Noggin or BMP4, specifically, using neutralizing antibodies suppressed endothelial cell formation; whereas, addition of rhBMP4 to cells treated with the hedgehog inhibitor cyclopamine rescued endothelial cell development. Our studies revealed that Ihh promoted human endothelial cell differentiation from pluripotent hES cells via BMP signaling, providing novel insights applicable to modulating human endothelial cell formation and vascular regeneration for human clinical therapies.

  10. Andrographolide inhibits nuclear factor-κB activation through JNK-Akt-p65 signaling cascade in tumor necrosis factor-α-stimulated vascular smooth muscle cells.

    Science.gov (United States)

    Chen, Yu-Ying; Hsu, Ming-Jen; Hsieh, Cheng-Ying; Lee, Lin-Wen; Chen, Zhih-Cherng; Sheu, Joen-Rong

    2014-01-01

    Critical vascular inflammation leads to vascular dysfunction and cardiovascular diseases, including abdominal aortic aneurysms, hypertension, and atherosclerosis. Andrographolide is the most active and critical constituent isolated from the leaves of Andrographis paniculata, a herbal medicine widely used for treating anti-inflammation in Asia. In this study, we investigated the mechanisms of the inhibitory effects of andrographolide in vascular smooth muscle cells (VSMCs) exposed to a proinflammatory stimulus, tumor necrosis factor-α (TNF-α). Treating TNF-α-stimulated VSMCs with andrographolide suppressed the expression of inducible nitric oxide synthase in a concentration-dependent manner. A reduction in TNF-α-induced c-Jun N-terminal kinase (JNK), Akt, and p65 phosphorylation was observed in andrographolide-treated VSMCs. However, andrographolide affected neither IκBα degradation nor p38 mitogen-activated protein kinase or extracellular signal-regulated kinase 1/2 phosphorylation under these conditions. Both treatment with LY294002, a phosphatidylinositol 3-kinase/Akt inhibitor, and treatment with SP600125, a JNK inhibitor, markedly reversed the andrographolide-mediated inhibition of p65 phosphorylation. In addition, LY294002 and SP600125 both diminished Akt phosphorylation, whereas LY294002 had no effects on JNK phosphorylation. These results collectively suggest that therapeutic interventions using andrographolide can benefit the treatment of vascular inflammatory diseases, and andrographolide-mediated inhibition of NF-κB activity in TNF-α-stimulated VSMCs occurs through the JNK-Akt-p65 signaling cascade, an IκBα-independent mechanism.

  11. Andrographolide Inhibits Nuclear Factor-κB Activation through JNK-Akt-p65 Signaling Cascade in Tumor Necrosis Factor-α-Stimulated Vascular Smooth Muscle Cells

    Directory of Open Access Journals (Sweden)

    Yu-Ying Chen

    2014-01-01

    Full Text Available Critical vascular inflammation leads to vascular dysfunction and cardiovascular diseases, including abdominal aortic aneurysms, hypertension, and atherosclerosis. Andrographolide is the most active and critical constituent isolated from the leaves of Andrographis paniculata, a herbal medicine widely used for treating anti-inflammation in Asia. In this study, we investigated the mechanisms of the inhibitory effects of andrographolide in vascular smooth muscle cells (VSMCs exposed to a proinflammatory stimulus, tumor necrosis factor-α (TNF-α. Treating TNF-α-stimulated VSMCs with andrographolide suppressed the expression of inducible nitric oxide synthase in a concentration-dependent manner. A reduction in TNF-α-induced c-Jun N-terminal kinase (JNK, Akt, and p65 phosphorylation was observed in andrographolide-treated VSMCs. However, andrographolide affected neither IκBα degradation nor p38 mitogen-activated protein kinase or extracellular signal-regulated kinase 1/2 phosphorylation under these conditions. Both treatment with LY294002, a phosphatidylinositol 3-kinase/Akt inhibitor, and treatment with SP600125, a JNK inhibitor, markedly reversed the andrographolide-mediated inhibition of p65 phosphorylation. In addition, LY294002 and SP600125 both diminished Akt phosphorylation, whereas LY294002 had no effects on JNK phosphorylation. These results collectively suggest that therapeutic interventions using andrographolide can benefit the treatment of vascular inflammatory diseases, and andrographolide-mediated inhibition of NF-κB activity in TNF-α-stimulated VSMCs occurs through the JNK-Akt-p65 signaling cascade, an IκBα-independent mechanism.

  12. Vascular smooth muscle cells exhibit a progressive loss of rigidity with serial culture passaging.

    Science.gov (United States)

    Dinardo, Carla Luana; Venturini, Gabriela; Omae, Samantha Vieira; Zhou, Enhua H; da Motta-Leal-Filho, Joaquim Maurício; Dariolli, Rafael; Krieger, José Eduardo; Alencar, Adriano Mesquita; Costa Pereira, Alexandre

    2012-01-01

    One drawback of in vitro cell culturing is the dedifferentiation process that cells experience. Smooth muscle cells (SMC) also change molecularly and morphologically with long term culture. The main objective of this study was to evaluate if culture passages interfere in vascular SMC mechanical behavior. SMC were obtained from five different porcine arterial beds. Optical magnetic twisting cytometry (OMTC) was used to characterize mechanically vascular SMC from different cultures in distinct passages and confocal microscopy/western blotting, to evaluate cytoskeleton and extracellular matrix proteins. We found that vascular SMC rigidity or viscoelastic complex modulus (G) decreases with progression of passages. A statistically significant negative correlation between G and passage was found in four of our five cultures studied. Phalloidin-stained SMC from higher passages exhibited lower mean signal intensity per cell (confocal microscopy) and quantitative western blotting analysis showed a decrease in collagen I content throughout passages. We concluded that vascular SMC progressively lose their stiffness with serial culture passaging. Thus, limiting the number of passages is essential for any experiment measuring viscoelastic properties of SMC in culture.

  13. Atorvastatin restores arsenic-induced vascular dysfunction in rats: Modulation of nitric oxide signaling and inflammatory mediators

    International Nuclear Information System (INIS)

    Kesavan, Manickam; Sarath, Thengumpallil Sasindran; Kannan, Kandasamy; Suresh, Subramaniyam; Gupta, Priyanka; Vijayakaran, Karunakaran; Sankar, Palanisamy; Kurade, Nitin Pandurang; Mishra, Santosh Kumar; Sarkar, Souvendra Nath

    2014-01-01

    We evaluated whether atorvastatin, an extensively prescribed statin for reducing the risks of cardiovascular diseases, can reduce the risk of arsenic-induced vascular dysfunction and inflammation in rats and whether the modulation could be linked to improvement in vascular NO signaling. Rats were exposed to sodium arsenite (100 ppm) through drinking water for 90 consecutive days. Atorvastatin (10 mg/kg bw, orally) was administered once daily during the last 30 days of arsenic exposure. On the 91 st day, blood was collected for measuring serum C-reactive protein. Thoracic aorta was isolated for assessing reactivity to phenylephrine, sodium nitroprusside and acetylcholine; evaluating eNOS and iNOS mRNA expression and measuring NO production, while abdominal aorta was used for ELISA of cytokines, chemokine and vascular cell adhesion molecules. Histopathology was done in aortic arches. Arsenic did not alter phenylephrine-elicited contraction. Atorvastatin inhibited E max of phenylephrine, but it augmented the contractile response in aortic rings from arsenic-exposed animals. Sodium nitroprusside-induced relaxation was not altered with any treatment. However, arsenic reduced acetylcholine-induced relaxation and affected aortic eNOS at the levels of mRNA expression, protein concentration, phosphorylation and NO production. Further, it increased aortic iNOS mRNA expression, iNOS-derived NO synthesis, production of pro-inflammatory mediators (IL-1β, IL-6, MCP-1, VCAM, sICAM) and serum C-reactive protein and aortic vasculopathic lesions. Atorvastatin attenuated these arsenic-mediated functional, biochemical and structural alterations. Results show that atorvastatin has the potential to ameliorate arsenic-induced vascular dysfunction and inflammation by restoring endothelial function with improvement in NO signaling and attenuating production of pro-inflammatory mediators and cell adhesion molecules. - Highlights: • We evaluated if atorvastatin reduce arsenic

  14. Atorvastatin restores arsenic-induced vascular dysfunction in rats: Modulation of nitric oxide signaling and inflammatory mediators

    Energy Technology Data Exchange (ETDEWEB)

    Kesavan, Manickam; Sarath, Thengumpallil Sasindran; Kannan, Kandasamy; Suresh, Subramaniyam; Gupta, Priyanka; Vijayakaran, Karunakaran; Sankar, Palanisamy; Kurade, Nitin Pandurang; Mishra, Santosh Kumar; Sarkar, Souvendra Nath, E-mail: snsarkar1911@rediffmail.com

    2014-10-01

    We evaluated whether atorvastatin, an extensively prescribed statin for reducing the risks of cardiovascular diseases, can reduce the risk of arsenic-induced vascular dysfunction and inflammation in rats and whether the modulation could be linked to improvement in vascular NO signaling. Rats were exposed to sodium arsenite (100 ppm) through drinking water for 90 consecutive days. Atorvastatin (10 mg/kg bw, orally) was administered once daily during the last 30 days of arsenic exposure. On the 91{sup st} day, blood was collected for measuring serum C-reactive protein. Thoracic aorta was isolated for assessing reactivity to phenylephrine, sodium nitroprusside and acetylcholine; evaluating eNOS and iNOS mRNA expression and measuring NO production, while abdominal aorta was used for ELISA of cytokines, chemokine and vascular cell adhesion molecules. Histopathology was done in aortic arches. Arsenic did not alter phenylephrine-elicited contraction. Atorvastatin inhibited E{sub max} of phenylephrine, but it augmented the contractile response in aortic rings from arsenic-exposed animals. Sodium nitroprusside-induced relaxation was not altered with any treatment. However, arsenic reduced acetylcholine-induced relaxation and affected aortic eNOS at the levels of mRNA expression, protein concentration, phosphorylation and NO production. Further, it increased aortic iNOS mRNA expression, iNOS-derived NO synthesis, production of pro-inflammatory mediators (IL-1β, IL-6, MCP-1, VCAM, sICAM) and serum C-reactive protein and aortic vasculopathic lesions. Atorvastatin attenuated these arsenic-mediated functional, biochemical and structural alterations. Results show that atorvastatin has the potential to ameliorate arsenic-induced vascular dysfunction and inflammation by restoring endothelial function with improvement in NO signaling and attenuating production of pro-inflammatory mediators and cell adhesion molecules. - Highlights: • We evaluated if atorvastatin reduce arsenic

  15. Angiotensin II increases phosphodiesterase 5A expression in vascular smooth muscle cells: A mechanism by which angiotensin II antagonizes cGMP signaling

    Science.gov (United States)

    Kim, Dongsoo; Aizawa, Toru; Wei, Heng; Pi, Xinchun; Rybalkin, Sergei D.; Berk, Bradford C.; Yan, Chen

    2014-01-01

    Angiotensin II (Ang II) and nitric oxide (NO)/natriuretic peptide (NP) signaling pathways mutually regulate each other. Imbalance of Ang II and NO/NP has been implicated in the pathophysiology of many vascular diseases. cGMP functions as a key mediator in the interaction between Ang II and NO/NP. Cyclic nucleotide phosphodiesterase 5A (PDE5A) is important in modulating cGMP signaling by hydrolyzing cGMP in vascular smooth muscle cells (VSMC). Therefore, we examined whether Ang II negatively modulates intracellular cGMP signaling in VSMC by regulating PDE5A. Ang II rapidly and transiently increased PDE5A mRNA levels in rat aortic VSMC. Upregulation of PDE5A mRNA was associated with a time-dependent increase of both PDE5 protein expression and activity. Increased PDE5A mRNA level was transcription-dependent and mediated by the Ang II type 1 receptor. Ang II-mediated activation of extracellular signal-regulated kinases 1/2 (ERK1/2) was essential for Ang II-induced PDE5A upregulation. Pretreatment of VSMC with Ang II inhibited C-type NP (CNP) stimulated cGMP signaling, such as cGMP dependent protein kinase (PKG)-mediated phosphorylation of vasodilator-stimulated-phosphoprotein (VASP). Ang II-mediated inhibition of PKG was blocked when PDE5 activity was decreased by selective PDE5 inhibitors, suggesting that upregulation of PDE5A expression is an important mechanism for Ang II to attenuate cGMP signaling. PDE5A may also play a critical role in the growth promoting effects of Ang II because inhibition of PDE5A activity significantly decreased Ang II-stimulated VSMC growth. These observations establish a new mechanism by which Ang II antagonizes cGMP signaling and stimulates VSMC growth. PMID:15623434

  16. Baicalein attenuates vinorelbine-induced vascular endothelial cell injury and chemotherapeutic phlebitis in rabbits

    International Nuclear Information System (INIS)

    Ge, Gang-Feng; Shi, Wei-Wen; Yu, Chen-Huan; Jin, Xiao-Yin; Zhang, Huan-Huan; Zhang, Wen-You; Wang, Lu-Chen; Yu, Bing

    2017-01-01

    Chemotherapy is one of the major strategies for cancer treatment. Several antineoplastic drugs including vinorelbine (VRB) are commonly intravenously infused and liable to cause serious phlebitis. The therapeutic drugs for preventing this complication are limited. In this study, the mechanism of baicalein (BCN) was investigated on VRB-induced phlebitis in vivo and vascular endothelial cell injury in vitro. Treatment with BCN obviously attenuated vascular endothelial cell loss, edema, inflammatory cell infiltration and blood clots, and reduced the serum levels of TNF-α, IL-1β, IL-6 and ICAM-1 in the rabbit model of phlebitis induced by intravenous injection of VRB compared with vehicle. Further tests in vitro demonstrated that BCN lessened VRB-induced endothelial cell apoptosis, decreased intracellular ROS levels, suppressed phosphorylation of p38 and eventually inhibited activation of NF-κB signaling pathway. And these effects could be reversed by p38 agonist P79350. These results suggested that BCN exerted the protective effects against VRB-induced endothelial disruption in the rabbit model of phlebitis via inhibition of intracellular ROS generation and inactivation of p38/NF-κB pathway, leading to the decreased production of pro-inflammatory cytokines. Thus, BCN could be used as a potential agent for the treatment of phlebitis. - Highlights: • Baicalein attenuated vinorelbine-induced vascular endothelial cell apoptosis. • Baicalein inhibited vinorelbine-induced oxidative stress in HUVECs. • Baicalein inhibited activation of p38/NF-κB signaling. • Baicalein attenuated vinorelbine-induced phlebitis and inflammation in rabbits.

  17. Baicalein attenuates vinorelbine-induced vascular endothelial cell injury and chemotherapeutic phlebitis in rabbits

    Energy Technology Data Exchange (ETDEWEB)

    Ge, Gang-Feng [Zhejiang Chinese Medical University, Hangzhou 310053 (China); Shi, Wei-Wen [Zhejiang Medical Science and Education Development Center, Hangzhou 310006 (China); Yu, Chen-Huan; Jin, Xiao-Yin; Zhang, Huan-Huan; Zhang, Wen-You [Key Laboratory of Experimental Animal and Safety Evaluation, Zhejiang Academy of Medical Sciences, Hangzhou 310013 (China); Wang, Lu-Chen [Zhejiang Chinese Medical University, Hangzhou 310053 (China); Yu, Bing, E-mail: Jellycook2002@163.com [Zhejiang Chinese Medical University, Hangzhou 310053 (China)

    2017-03-01

    Chemotherapy is one of the major strategies for cancer treatment. Several antineoplastic drugs including vinorelbine (VRB) are commonly intravenously infused and liable to cause serious phlebitis. The therapeutic drugs for preventing this complication are limited. In this study, the mechanism of baicalein (BCN) was investigated on VRB-induced phlebitis in vivo and vascular endothelial cell injury in vitro. Treatment with BCN obviously attenuated vascular endothelial cell loss, edema, inflammatory cell infiltration and blood clots, and reduced the serum levels of TNF-α, IL-1β, IL-6 and ICAM-1 in the rabbit model of phlebitis induced by intravenous injection of VRB compared with vehicle. Further tests in vitro demonstrated that BCN lessened VRB-induced endothelial cell apoptosis, decreased intracellular ROS levels, suppressed phosphorylation of p38 and eventually inhibited activation of NF-κB signaling pathway. And these effects could be reversed by p38 agonist P79350. These results suggested that BCN exerted the protective effects against VRB-induced endothelial disruption in the rabbit model of phlebitis via inhibition of intracellular ROS generation and inactivation of p38/NF-κB pathway, leading to the decreased production of pro-inflammatory cytokines. Thus, BCN could be used as a potential agent for the treatment of phlebitis. - Highlights: • Baicalein attenuated vinorelbine-induced vascular endothelial cell apoptosis. • Baicalein inhibited vinorelbine-induced oxidative stress in HUVECs. • Baicalein inhibited activation of p38/NF-κB signaling. • Baicalein attenuated vinorelbine-induced phlebitis and inflammation in rabbits.

  18. Tetraspanin CD9 regulates cell contraction and actin arrangement via RhoA in human vascular smooth muscle cells.

    Directory of Open Access Journals (Sweden)

    Michael J Herr

    Full Text Available The most prevalent cardiovascular diseases arise from alterations in vascular smooth muscle cell (VSMC morphology and function. Tetraspanin CD9 has been previously implicated in regulating vascular pathologies; however, insight into how CD9 may regulate adverse VSMC phenotypes has not been provided. We utilized a human model of aortic smooth muscle cells to understand the consequences of CD9 deficiency on VSMC phenotypes. Upon knocking down CD9, the cells developed an abnormally small and rounded morphology. We determined that this morphological change was due to a lack of typical parallel actin arrangement. We also found similar total RhoA but decreased GTP-bound (active RhoA levels in CD9 deficient cells. As a result, cells lacking a full complement of CD9 were less contractile than their control treated counterparts. Upon restoration of RhoA activity in the CD9 deficient cells, the phenotype was reversed and cell contraction was restored. Conversely, inhibition of RhoA activity in the control cells mimicked the CD9-deficient cell phenotype. Thus, alteration in CD9 expression was sufficient to profoundly disrupt cellular actin arrangement and endogenous cell contraction by interfering with RhoA signaling. This study provides insight into how CD9 may regulate previously described vascular smooth muscle cell pathophysiology.

  19. Antioxidant and signal modulation properties of plant polyphenols in controlling vascular inflammation.

    Science.gov (United States)

    Kostyuk, Vladimir A; Potapovich, Alla I; Suhan, Tatyana O; de Luca, Chiara; Korkina, Liudmila G

    2011-05-11

    Oxidized low-density lipoproteins (oxLDL) play a critical role in the initiation of atherosclerosis through activation of inflammatory signaling. In the present work we investigated the role of antioxidant and signal modulation properties of plant polyphenols in controlling vascular inflammation. Significant decrease in intracellular NO level and superoxide overproduction was found in human umbilical vein endothelial cells (HUVEC) treated with oxLDL, but not with LDL. The redox imbalance was prevented by the addition of quercetin or resveratrol. Expression analysis of 14 genes associated with oxidative stress and inflammation revealed oxLDL-mediated up-regulation of genes specifically involved in leukocyte recruitment and adhesion. This up-regulation could be partially avoided by the addition of verbascoside or resveratrol, while treatment with quercetin resulted in a further increase in the expression of these genes. Lipopolysaccharide (LPS)-treated HUVEC were also used for the evaluation of anti-inflammatory potency of plant polyphenols. Significant differences between HUVEC treaded with oxLDL and LPS were found in both the expression pattern of inflammation-related genes and the effects of plant polyphenols on cellular responses. The present data indicate that plant polyphenols may affect vascular inflammation not only as antioxidants but also as modulators of inflammatory redox signaling pathways. Crown Copyright © 2011. Published by Elsevier B.V. All rights reserved.

  20. 3,3'Diindolylmethane suppresses vascular smooth muscle cell phenotypic modulation and inhibits neointima formation after carotid injury.

    Directory of Open Access Journals (Sweden)

    Hongjing Guan

    Full Text Available 3,3'Diindolylmethane (DIM, a natural phytochemical, has shown inhibitory effects on the growth and migration of a variety of cancer cells; however, whether DIM has similar effects on vascular smooth muscle cells (VSMCs remains unknown. The purpose of this study was to assess the effects of DIM on the proliferation and migration of cultured VSMCs and neointima formation in a carotid injury model, as well as the related cell signaling mechanisms.DIM dose-dependently inhibited the platelet-derived growth factor (PDGF-BB-induced proliferation of VSMCs without cell cytotoxicity. This inhibition was caused by a G0/G1 phase cell cycle arrest demonstrated by fluorescence-activated cell-sorting analysis. We also showed that DIM-induced growth inhibition was associated with the inhibition of the expression of cyclin D1 and cyclin-dependent kinase (CDK 4/6 as well as an increase in p27(Kip1 levels in PDGF-stimulated VSMCs. Moreover, DIM was also found to modulate migration of VSMCs and smooth muscle-specific contractile marker expression. Mechanistically, DIM negatively modulated PDGF-BB-induced phosphorylation of PDGF-recptorβ (PDGF-Rβ and the activities of downstream signaling molecules including Akt/glycogen synthase kinase(GSK3β, extracellular signal-regulated kinase1/2 (ERK1/2, and signal transducers and activators of transcription 3 (STAT3. Our in vivo studies using a mouse carotid arterial injury model revealed that treatment with 150 mg/kg DIM resulted in significant reduction of the neointima/media ratio and proliferating cell nuclear antigen (PCNA-positive cells, without affecting apoptosis of vascular cells and reendothelialization. Infiltration of inflammatory cells was also inhibited by DIM administration.These results demonstrate that DIM can suppress the phenotypic modulation of VSMCs and neointima hyperplasia after vascular injury. These beneficial effects on VSMCs were at least partly mediated by the inhibition of PDGF-Rβ and the

  1. Tyk2 mediates effects of urokinase on human vascular smooth muscle cell growth

    International Nuclear Information System (INIS)

    Patecki, Margret; Schaewen, Markus von; Tkachuk, Sergey; Jerke, Uwe; Dietz, Rainer; Dumler, Inna; Kusch, Angelika

    2007-01-01

    The urokinase (uPA)/uPA receptor (uPAR) system plays a role in the response of the vessel wall to injury, presumably by modulating vascular smooth muscle cell (VSMC) functional behaviour. The Jak/Stat signaling pathway has been implicated to mediate the uPA/uPAR-directed cell migration and proliferation in VSMC. We have therefore investigated the underlying molecular mechanisms, which remained not completely understood. In particular, we aimed at identification of the kinase involved in the signaling cascade leading to Stat1 phosphorylation by uPA and its impact on VSMC growth. We performed expression in VSMC of kinase-deficient mutant forms of the Janus kinases Jak1 and Tyk2 and used different cell culture models imitating the response to vascular injury. We provide evidence that Tyk2, but not Jak1, mediates uPA-induced Stat1 phosphorylation and VSMC growth inhibition and suggest a novel function for Tyk2 as an important modulator of the uPA-directed VSMC functional behaviour at the place of injury

  2. Camptothecin inhibits platelet-derived growth factor-BB-induced proliferation of rat aortic vascular smooth muscle cells through inhibition of PI3K/Akt signaling pathway

    Energy Technology Data Exchange (ETDEWEB)

    Park, Eun-Seok [Department of Applied Biochemistry, Division of Life Science, College of Health and Biomedical Science, Konkuk University, Chungju, Chungbuk (Korea, Republic of); Kang, Shin-il [College of Pharmacy Medical Research Center, Chungbuk National University, Cheongju (Korea, Republic of); Yoo, Kyu-dong [Hazardous Substances Analysis Division, Gwangju Regional Food and Drug Administration, Gwangju (Korea, Republic of); Lee, Mi-Yea [Department of Nursing Kyungbok University, Pocheon (Korea, Republic of); Yoo, Hwan-Soo; Hong, Jin-Tae [College of Pharmacy Medical Research Center, Chungbuk National University, Cheongju (Korea, Republic of); Shin, Hwa-Sup [Department of Applied Biochemistry, Division of Life Science, College of Health and Biomedical Science, Konkuk University, Chungju, Chungbuk (Korea, Republic of); Kim, Bokyung [Department of Physiology, Konkuk Medical School, Konkuk University, Chungju, Chungbuk (Korea, Republic of); Yun, Yeo-Pyo, E-mail: ypyun@chungbuk.ac.kr [College of Pharmacy Medical Research Center, Chungbuk National University, Cheongju (Korea, Republic of)

    2013-04-15

    The abnormal proliferation of vascular smooth muscle cells (VSMCs) in arterial wall is a major cause of vascular disorders such as atherosclerosis and restenosis after angioplasty. In this study, we investigated not only the inhibitory effects of camptothecin (CPT) on PDGF-BB-induced VSMC proliferation, but also its molecular mechanism of this inhibition. CPT significantly inhibited proliferation with IC50 value of 0.58 μM and the DNA synthesis of PDGF-BB-stimulated VSMCs in a dose-dependent manner (0.5–2 μM ) without any cytotoxicity. CPT induced the cell cycle arrest at G0/G1 phase. Also, CPT decreased the expressions of G0/G1-specific regulatory proteins including cyclin-dependent kinase (CDK)2, cyclin D1 and PCNA in PDGF-BB-stimulated VSMCs. Pre-incubation of VSMCs with CPT significantly inhibited PDGF-BB-induced Akt activation, whereas CPT did not affect PDGF-receptor beta phosphorylation, extracellular signal-regulated kinase (ERK) 1/2 phosphorylation and phospholipase C (PLC)-γ1 phosphorylation in PDGF-BB signaling pathway. Our data showed that CPT pre-treatment inhibited VSMC proliferation, and that the inhibitory effect of CPT was enhanced by LY294002, a PI3K inhibitor, on PDGF-BB-induced VSMC proliferation. In addition, inhibiting the PI3K/Akt pathway by LY294002 significantly enhanced the suppression of PCNA expression and Akt activation by CPT. These results suggest that the anti-proliferative activity of CPT is mediated in part by downregulating the PI3K/Akt signaling pathway. - Highlights: ► CPT inhibits proliferation of PDGF-BB-induced VSMC without cytotoxicity. ► CPT arrests the cell cycle in G0/G1 phase by downregulation of cyclin D1 and CDK2. ► CPT significantly attenuates Akt phosphorylation in PDGF-BB signaling pathway. ► LY294002 enhanced the inhibitory effect of CPT on VSMC proliferation. ► Thus, CPT is mediated by downregulating the PI3K/Akt signaling pathway.

  3. Camptothecin inhibits platelet-derived growth factor-BB-induced proliferation of rat aortic vascular smooth muscle cells through inhibition of PI3K/Akt signaling pathway

    International Nuclear Information System (INIS)

    Park, Eun-Seok; Kang, Shin-il; Yoo, Kyu-dong; Lee, Mi-Yea; Yoo, Hwan-Soo; Hong, Jin-Tae; Shin, Hwa-Sup; Kim, Bokyung; Yun, Yeo-Pyo

    2013-01-01

    The abnormal proliferation of vascular smooth muscle cells (VSMCs) in arterial wall is a major cause of vascular disorders such as atherosclerosis and restenosis after angioplasty. In this study, we investigated not only the inhibitory effects of camptothecin (CPT) on PDGF-BB-induced VSMC proliferation, but also its molecular mechanism of this inhibition. CPT significantly inhibited proliferation with IC50 value of 0.58 μM and the DNA synthesis of PDGF-BB-stimulated VSMCs in a dose-dependent manner (0.5–2 μM ) without any cytotoxicity. CPT induced the cell cycle arrest at G0/G1 phase. Also, CPT decreased the expressions of G0/G1-specific regulatory proteins including cyclin-dependent kinase (CDK)2, cyclin D1 and PCNA in PDGF-BB-stimulated VSMCs. Pre-incubation of VSMCs with CPT significantly inhibited PDGF-BB-induced Akt activation, whereas CPT did not affect PDGF-receptor beta phosphorylation, extracellular signal-regulated kinase (ERK) 1/2 phosphorylation and phospholipase C (PLC)-γ1 phosphorylation in PDGF-BB signaling pathway. Our data showed that CPT pre-treatment inhibited VSMC proliferation, and that the inhibitory effect of CPT was enhanced by LY294002, a PI3K inhibitor, on PDGF-BB-induced VSMC proliferation. In addition, inhibiting the PI3K/Akt pathway by LY294002 significantly enhanced the suppression of PCNA expression and Akt activation by CPT. These results suggest that the anti-proliferative activity of CPT is mediated in part by downregulating the PI3K/Akt signaling pathway. - Highlights: ► CPT inhibits proliferation of PDGF-BB-induced VSMC without cytotoxicity. ► CPT arrests the cell cycle in G0/G1 phase by downregulation of cyclin D1 and CDK2. ► CPT significantly attenuates Akt phosphorylation in PDGF-BB signaling pathway. ► LY294002 enhanced the inhibitory effect of CPT on VSMC proliferation. ► Thus, CPT is mediated by downregulating the PI3K/Akt signaling pathway

  4. Sirtuins, Cell Senescence, and Vascular Aging.

    Science.gov (United States)

    Kida, Yujiro; Goligorsky, Michael S

    2016-05-01

    The sirtuins (SIRTs) constitute a class of proteins with nicotinamide adenine dinucleotide-dependent deacetylase or adenosine diphosphate-ribosyltransferase activity. Seven SIRT family members have been identified in mammals, from SIRT1, the best studied for its role in vascular aging, to SIRT7. SIRT1 and SIRT2 are localized in the nucleus and cytoplasm. SIRT3, SIRT4, and SIRT5 are mitochondrial, and SIRT6 and SIRT7 are nuclear. Extensive studies have clearly revealed that SIRT proteins regulate diverse cell functions and responses to stressors. Vascular aging involves the aging process (senescence) of endothelial and vascular smooth muscle cells. Two types of cell senescence have been identified: (1) replicative senescence with telomere attrition; and (2) stress-induced premature senescence without telomere involvement. Both types of senescence induce vascular cell growth arrest and loss of vascular homeostasis, and contribute to the initiation and progression of cardiovascular diseases. Previous mechanistic studies have revealed in detail that SIRT1, SIRT3, and SIRT6 show protective functions against vascular aging, and definite vascular function of other SIRTs is under investigation. Thus, direct SIRT modulation and nicotinamide adenine dinucleotide stimulation of SIRT are promising candidates for cardiovascular disease therapy. A small number of pilot studies have been conducted to assess SIRT modulation in humans. These clinical studies have not yet provided convincing evidence that SIRT proteins alleviate morbidity and mortality in patients with cardiovascular diseases. The outcomes of multiple ongoing clinical trials are awaited to define the efficacy of SIRT modulators and SIRT activators in cardiovascular diseases, along with the potential adverse effects of chronic SIRT modulation. Copyright © 2016 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.

  5. A novel adipocytokine, chemerin exerts anti-inflammatory roles in human vascular endothelial cells

    Energy Technology Data Exchange (ETDEWEB)

    Yamawaki, Hideyuki, E-mail: yamawaki@vmas.kitasato-u.ac.jp [Laboratory of Veterinary Pharmacology, School of Veterinary Medicine, Kitasato University, Aomori 034-8628 (Japan); Kameshima, Satoshi; Usui, Tatsuya; Okada, Muneyoshi; Hara, Yukio [Laboratory of Veterinary Pharmacology, School of Veterinary Medicine, Kitasato University, Aomori 034-8628 (Japan)

    2012-06-22

    Highlights: Black-Right-Pointing-Pointer Chemerin is a novel adipocytokine with almost unknown function in vasculature. Black-Right-Pointing-Pointer Chemerin activates Akt/eNOS/NO pathways in endothelial cells. Black-Right-Pointing-Pointer Chemerin inhibits TNF-{alpha}-induced monocyte adhesion to endothelial cells. Black-Right-Pointing-Pointer Chemerin inhibits TNF-induced VCAM-1 via suppressing NF-{kappa}B and p38 signal. Black-Right-Pointing-Pointer Chemerin is anti-inflammatory through producing NO in vascular endothelium. -- Abstract: Chemerin is a recently identified adipocytokine which plays a role on inflammation and adipocytes metabolism. However, its function in vasculature is largely unknown. We examined the effects of chemerin on vascular endothelial inflammatory states. Treatment of human umbilical vein endothelial cells with chemerin (300 ng/ml, 20 min) induced phosphorylation of Akt (Ser473) and endothelial nitric oxide (NO) synthase (eNOS) (Ser1177). Consistently, chemerin increased intracellular cyclic GMP content. Pretreatment with chemerin (1-300 ng/ml, 24 h) significantly inhibited phosphorylation of nuclear factor (NF)-{kappa}B p65 (Ser536) and p38 as well as vascular cell adhesion molecule (VCAM)-1 expression induced by tumor necrosis factor (TNF)-{alpha} (5 ng/ml, 20 min-6 h). Inhibitor of NF-{kappa}B or p38 significantly inhibited the TNF-{alpha}-induced VCAM-1 expression. Chemerin also inhibited TNF-{alpha}-induced VCAM-1 expression in rat isolated aorta. Moreover, chemerin significantly inhibited monocytes adhesion to TNF-{alpha}-stimulated endothelial cells. The inhibitory effect of chemerin on TNF-{alpha}-induced VCAM-1 was reversed by a NOS inhibitor. Conversely, an NO donor, sodium nitroprusside significantly inhibited TNF-{alpha}-induced VCAM-1. The present results for the first time demonstrate that chemerin plays anti-inflammatory roles by preventing TNF-{alpha}-induced VCAM-1 expression and monocytes adhesion in vascular

  6. Proteolytic degradation of regulator of G protein signaling 2 facilitates temporal regulation of Gq/11 signaling and vascular contraction.

    Science.gov (United States)

    Kanai, Stanley M; Edwards, Alethia J; Rurik, Joel G; Osei-Owusu, Patrick; Blumer, Kendall J

    2017-11-24

    Regulator of G protein signaling 2 (RGS2) controls signaling by receptors coupled to the G q/11 class heterotrimeric G proteins. RGS2 deficiency causes several phenotypes in mice and occurs in several diseases, including hypertension in which a proteolytically unstable RGS2 mutant has been reported. However, the mechanisms and functions of RGS2 proteolysis remain poorly understood. Here we addressed these questions by identifying degradation signals in RGS2, and studying dynamic regulation of G q/11 -evoked Ca 2+ signaling and vascular contraction. We identified a novel bipartite degradation signal in the N-terminal domain of RGS2. Mutations disrupting this signal blunted proteolytic degradation downstream of E3 ubiquitin ligase binding to RGS2. Analysis of RGS2 mutants proteolyzed at various rates and the effects of proteasome inhibition indicated that proteolytic degradation controls agonist efficacy by setting RGS2 protein expression levels, and affecting the rate at which cells regain agonist responsiveness as synthesis of RGS2 stops. Analyzing contraction of mesenteric resistance arteries supported the biological relevance of this mechanism. Because RGS2 mRNA expression often is strikingly and transiently up-regulated and then down-regulated upon cell stimulation, our findings indicate that proteolytic degradation tightly couples RGS2 transcription, protein levels, and function. Together these mechanisms provide tight temporal control of G q/11 -coupled receptor signaling in the cardiovascular, immune, and nervous systems. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

  7. Cellular function and signaling pathways of vascular smooth muscle cells modulated by sphingosine 1-phosphate

    Directory of Open Access Journals (Sweden)

    Takuji Machida

    2016-12-01

    Full Text Available Sphingosine 1-phosphate (S1P plays important roles in cardiovascular pathophysiology. S1P1 and/or S1P3, rather than S1P2 receptors, seem to be predominantly expressed in vascular endothelial cells, while S1P2 and/or S1P3, rather than S1P1 receptors, seem to be predominantly expressed in vascular smooth muscle cells (VSMCs. S1P has multiple actions, such as proliferation, inhibition or stimulation of migration, and vasoconstriction or release of vasoactive mediators. S1P induces an increase of the intracellular Ca2+ concentration in many cell types, including VSMCs. Activation of S1P3 seems to play an important role in Ca2+ mobilization. S1P induces cyclooxygenase-2 expression in VSMCs via both S1P2 and S1P3 receptors. S1P2 receptor activation in VSMCs inhibits inducible nitric oxide synthase (iNOS expression. At the local site of vascular injury, vasoactive mediators such as prostaglandins and NO produced by VSMCs are considered primarily as a defensive and compensatory mechanism for the lack of endothelial function to prevent further pathology. Therefore, selective S1P2 receptor antagonists may have the potential to be therapeutic agents, in view of their antagonism of iNOS inhibition by S1P. Further progress in studies of the precise mechanisms of S1P may provide useful knowledge for the development of new S1P-related drugs for the treatment of cardiovascular diseases.

  8. Andrographolide, a Novel NF-κB Inhibitor, Induces Vascular Smooth Muscle Cell Apoptosis via a Ceramide-p47phox-ROS Signaling Cascade

    Directory of Open Access Journals (Sweden)

    Yu-Ying Chen

    2013-01-01

    Full Text Available Atherosclerosis is linked with the development of many cardiovascular complications. Abnormal proliferation of vascular smooth muscle cells (VSMCs plays a crucial role in the development of atherosclerosis. Accordingly, the apoptosis of VSMCs, which occurs in the progression of vascular proliferation, may provide a beneficial strategy for managing cardiovascular diseases. Andrographolide, a novel nuclear factor-κB inhibitor, is the most active and critical constituent isolated from the leaves of Andrographis paniculata. Recent studies have indicated that andrographolide is a potential therapeutic agent for treating cancer through the induction of apoptosis. In this study, the apoptosis-inducing activity and mechanisms in andrographolide-treated rat VSMCs were characterized. Andrographolide significantly induced reactive oxygen species (ROS formation, p53 activation, Bax, and active caspase-3 expression, and these phenomena were suppressed by pretreating the cells with N-acetyl-L-cysteine, a ROS scavenger, or diphenylene iodonium, a nicotinamide adenine dinucleotide phosphate (NADPH oxidase (Nox inhibitor. Furthermore, p47phox, a Nox subunit protein, was phosphorylated in andrographolide-treated rat VSMCs. However, pretreatment with 3-O-methyl-sphingomyelin, a neutral sphingomyelinase inhibitor, significantly inhibited andrographolide-induced p47phox phosphorylation as well as Bax and active caspase-3 expression. Our results collectively demonstrate that andrographolide-reduced cell viability can be attributed to apoptosis in VSMCs, and this apoptosis-inducing activity was associated with the ceramide-p47phox-ROS signaling cascade.

  9. Brazilin Ameliorates High Glucose-Induced Vascular Inflammation via Inhibiting ROS and CAMs Production in Human Umbilical Vein Endothelial Cells

    Directory of Open Access Journals (Sweden)

    Thanasekaran Jayakumar

    2014-01-01

    Full Text Available Vascular inflammatory process has been suggested to play a key role in the initiation and progression of atherosclerosis, a major complication of diabetes mellitus. Recent studies have shown that brazilin exhibits antihepatotoxic, antiplatelet, cancer preventive, or anti-inflammatory properties. Thus, we investigated whether brazilin suppresses vascular inflammatory process induced by high glucose (HG in cultured human umbilical vein endothelial cells (HUVEC. HG induced nitrite production, lipid peroxidation, and intracellular reactive oxygen species formation in HUVEC cells, which was reversed by brazilin. Western blot analysis revealed that brazilin markedly inhibited HG-induced phosphorylation of endothelial nitric oxide synthase. Besides, we investigated the effects of brazilin on the MAPK signal transduction pathway because MAPK families are associated with vascular inflammation under stress. Brazilin blocked HG-induced phosphorylation of extracellular signal-regulated kinase and transcription factor NF-κB. Furthermore, brazilin concentration-dependently attenuated cell adhesion molecules (ICAM-1 and VCAM-1 expression induced by various concentrations of HG in HUVEC. Taken together, the present data suggested that brazilin could suppress high glucose-induced vascular inflammatory process, which may be closely related with the inhibition of oxidative stress, CAMs expression, and NF-κB activation in HUVEC. Our findings may highlight a new therapeutic intervention for the prevention of vascular diseases.

  10. TW-01, a piperazinedione-derived compound, inhibits Ras-mediated cell proliferation and angioplasty-induced vascular restenosis

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Chao-Feng [The Ph.D. Program for Cancer Biology and Drug Discovery, College of Medical Science and Technology, Taipei Medical University, Taipei 11031, Taiwan (China); Department of Medicine, MacKay Medical College, New Taipei City, Taiwan (China); Division of Cardiology, Department of Internal Medicine, MacKay Memorial Hospital, Taipei, Taiwan (China); Division of Cardiology, Department of Internal Medicine, Shuang Ho Hospital, Taipei Medical University, New Taipei City, Taiwan (China); Huang, Han-Li [The Ph.D. Program for Cancer Biology and Drug Discovery, College of Medical Science and Technology, Taipei Medical University, Taipei 11031, Taiwan (China); Peng, Chieh-Yu [Chinese Medicine Research and Development Center, China Medical University Hospital, Taichung 404, Taiwan (China); School of Pharmacy, College of Pharmacy, China Medical University, Taichung 404, Taiwan (China); Lee, Yu-Ching [The Center of Translational Medicine, Taipei Medical University, Taipei, Taiwan (China); Ph.D. Program for Biotechnology in Medicine, Taipei Medical University, Taipei, Taiwan (China); Wang, Hui-Po [College of Pharmacy, Taipei Medical University, Taipei 11031, Taiwan (China); Teng, Che-Ming [College of Pharmacy, Taipei Medical University, Taipei 11031, Taiwan (China); Pharmacological Institute, College of Medicine, National Taiwan University, Taipei 100, Taiwan (China); Pan, Shiow-Lin, E-mail: slpan@tmu.edu.tw [The Ph.D. Program for Cancer Biology and Drug Discovery, College of Medical Science and Technology, Taipei Medical University, Taipei 11031, Taiwan (China); Department of Pharmacology, College of Medicine, Taipei Medical University, Taipei 10031, Taiwan (China)

    2016-08-15

    Purpose: Vascular smooth muscle cell (VSMC) proliferation plays a critical role in the pathogenesis of atherosclerosis and restenosis. This study investigated piperazinedione derived compound TW-01-mediated inhibitory effects on VSMC proliferation and intimal hyperplasia. Methods: Cell proliferation was determined using [{sup 3}H]-thymidine incorporation and MTT assay; cell cycle distribution was measured using flow cytometry; proteins and mRNA expression were determined using western blotting and RT-PCR analyses; DNA binding activity of nuclear factor-κB (NF-κB), as measured using enzyme-linked immunosorbent assays (ELISA); in vivo effects of TW-01 were determined using balloon angioplasty in the rat. Results: TW-01 significantly inhibited cell proliferation. At the concentrations used, no cytotoxic effects were observed. Three predominant signaling pathways were inhibited by TW-01: (a) extracellular signal-regulated kinase (ERK)1/2 mitogen-activated protein kinase (MAPK) activation and its downstream effectors of c-fos, c-jun, and c-myc; (b) DNA binding activity of nuclear factor-κB (NF-κB); and, (c) Akt/protein kinase B (PKB) and cell cycle progression. Furthermore, TW-01 also inhibited Ras activation, a shared upstream event of each of these signaling cascades. In vascular injury studies, oral administration of TW-01 significantly suppressed intimal hyperplasia induced by balloon angioplasty. Conclusion: The present study suggests that TW-01 might be a potential candidate for atherosclerosis treatment. - Highlights: • TW-01significantly inhibits vascular smooth muscle cell proliferation. • TW-01 inhibits ERK, Akt and Ras pathway and DNA binding activity of NF-κB. • TW-01 significantly suppresses intimal hyperplasia induced by balloon angioplasty. • TW-01 might be a potential candidate for atherosclerosis treatment.

  11. TW-01, a piperazinedione-derived compound, inhibits Ras-mediated cell proliferation and angioplasty-induced vascular restenosis

    International Nuclear Information System (INIS)

    Lin, Chao-Feng; Huang, Han-Li; Peng, Chieh-Yu; Lee, Yu-Ching; Wang, Hui-Po; Teng, Che-Ming; Pan, Shiow-Lin

    2016-01-01

    Purpose: Vascular smooth muscle cell (VSMC) proliferation plays a critical role in the pathogenesis of atherosclerosis and restenosis. This study investigated piperazinedione derived compound TW-01-mediated inhibitory effects on VSMC proliferation and intimal hyperplasia. Methods: Cell proliferation was determined using [ 3 H]-thymidine incorporation and MTT assay; cell cycle distribution was measured using flow cytometry; proteins and mRNA expression were determined using western blotting and RT-PCR analyses; DNA binding activity of nuclear factor-κB (NF-κB), as measured using enzyme-linked immunosorbent assays (ELISA); in vivo effects of TW-01 were determined using balloon angioplasty in the rat. Results: TW-01 significantly inhibited cell proliferation. At the concentrations used, no cytotoxic effects were observed. Three predominant signaling pathways were inhibited by TW-01: (a) extracellular signal-regulated kinase (ERK)1/2 mitogen-activated protein kinase (MAPK) activation and its downstream effectors of c-fos, c-jun, and c-myc; (b) DNA binding activity of nuclear factor-κB (NF-κB); and, (c) Akt/protein kinase B (PKB) and cell cycle progression. Furthermore, TW-01 also inhibited Ras activation, a shared upstream event of each of these signaling cascades. In vascular injury studies, oral administration of TW-01 significantly suppressed intimal hyperplasia induced by balloon angioplasty. Conclusion: The present study suggests that TW-01 might be a potential candidate for atherosclerosis treatment. - Highlights: • TW-01significantly inhibits vascular smooth muscle cell proliferation. • TW-01 inhibits ERK, Akt and Ras pathway and DNA binding activity of NF-κB. • TW-01 significantly suppresses intimal hyperplasia induced by balloon angioplasty. • TW-01 might be a potential candidate for atherosclerosis treatment.

  12. New aspects of vascular remodelling: the involvement of all vascular cell types.

    Science.gov (United States)

    McGrath, John C; Deighan, Clare; Briones, Ana M; Shafaroudi, Majid Malekzadeh; McBride, Melissa; Adler, Jeremy; Arribas, Silvia M; Vila, Elisabet; Daly, Craig J

    2005-07-01

    Conventionally, the architecture of arteries is based around the close-packed smooth muscle cells and extracellular matrix. However, the adventitia and endothelium are now viewed as key players in vascular growth and repair. A new dynamic picture has emerged of blood vessels in a constant state of self-maintenance. Recent work raises fundamental questions about the cellular heterogeneity of arteries and the time course and triggering of normal and pathological remodelling. A common denominator emerging in hypertensive remodelling is an early increase in adventitial cell density suggesting that adventitial cells drive remodelling and may initiate subsequent changes such as re-arrangement of smooth muscle cells and extracellular matrix. The organization of vascular smooth muscle cells follows regular arrangements that can be modelled mathematically. In hypertension, new patterns can be quantified in these terms and give insights to how structure affects function. As with smooth muscle, little is known about the organization of the vascular endothelium, or its role in vascular remodelling. Current observations suggest that there may be a close relationship between the helical organization of smooth muscle cells and the underlying pattern of endothelial cells. The function of myoendothelial connections is a topic of great current interest and may relate to the structure of the internal elastic lamina through which the connections must pass. In hypertensive remodelling this must present an organizational challenge. The objective of this paper is to show how the functions of blood vessels depend on their architecture and a continuous interaction of different cell types and extracellular proteins.

  13. MiR-137 inhibited cell proliferation and migration of vascular smooth muscle cells via targeting IGFBP-5 and modulating the mTOR/STAT3 signaling.

    Directory of Open Access Journals (Sweden)

    Jin Pan

    Full Text Available Abnormal proliferation of vascular smooth muscle cells (VSMCs contributes to the development of cardiovascular diseases. Studies have shown the great impact of microRNAs (miRNAs on the cell proliferation of VSMCs. This study examined the effects of miR-137 on the cell proliferation and migration of VSMCs and also explored the underlying molecular mechanisms. The mRNA and protein expression levels were determined by qRT-PCR and western blot assays, respectively. The CCK-8 assay, wound healing assay and transwell migration assay were performed to measure cell proliferation and migration of VSMCs. The miR-137-targeted 3'untranslated region of insulin-like growth factor-binding protein-5 (IGFBP-5 was confirmed by luciferase reporter assay. Platelet-derived growth factor-bb (PDGF-bb treatment enhanced cell proliferation and suppressed the expression of miR-137 in VSMCs. The gain-of-function and loss-of-function assays showed that overexpression of miR-137 suppressed the cell proliferation and migration, and also inhibited the expression of matrix genes of VSMCs; down-regulation of miR-137 had the opposite effects on VSMCs. Bioinformatics analysis and luciferase report assay results showed that IGFBP-5 was a direct target of miR-137, and miR-137 overexpression suppressed the IGFBP-5 expression and down-regulation of miR-137 increased the IGFBP-5 expression in VSMCs. PDGF-bb treatment also increased the IGFBP-5 mRNA expression. In addition, enforced expression of IGFBP-5 reversed the inhibitory effects of miR-137 on cell proliferation and migration of VSMCs. More importantly, overexpression of miR-137 also suppressed the activity of mTOR/STAT3 signaling in VSMCs. Taken together, the results suggest that miR-137 may suppress cell proliferation and migration of VSMCs via targeting IGFBP-5 and modulating mTOR/STAT3 signaling pathway.

  14. Regulation of Cellular Redox Signaling by Matricellular Proteins in Vascular Biology, Immunology, and Cancer.

    Science.gov (United States)

    Roberts, David D; Kaur, Sukhbir; Isenberg, Jeffrey S

    2017-10-20

    In contrast to structural elements of the extracellular matrix, matricellular proteins appear transiently during development and injury responses, but their sustained expression can contribute to chronic disease. Through interactions with other matrix components and specific cell surface receptors, matricellular proteins regulate multiple signaling pathways, including those mediated by reactive oxygen and nitrogen species and H 2 S. Dysregulation of matricellular proteins contributes to the pathogenesis of vascular diseases and cancer. Defining the molecular mechanisms and receptors involved is revealing new therapeutic opportunities. Recent Advances: Thrombospondin-1 (TSP1) regulates NO, H 2 S, and superoxide production and signaling in several cell types. The TSP1 receptor CD47 plays a central role in inhibition of NO signaling, but other TSP1 receptors also modulate redox signaling. The matricellular protein CCN1 engages some of the same receptors to regulate redox signaling, and ADAMTS1 regulates NO signaling in Marfan syndrome. In addition to mediating matricellular protein signaling, redox signaling is emerging as an important pathway that controls the expression of several matricellular proteins. Redox signaling remains unexplored for many matricellular proteins. Their interactions with multiple cellular receptors remains an obstacle to defining signaling mechanisms, but improved transgenic models could overcome this barrier. Therapeutics targeting the TSP1 receptor CD47 may have beneficial effects for treating cardiovascular disease and cancer and have recently entered clinical trials. Biomarkers are needed to assess their effects on redox signaling in patients and to evaluate how these contribute to their therapeutic efficacy and potential side effects. Antioxid. Redox Signal. 27, 874-911.

  15. Stem cell-derived vascular endothelial cells and their potential application in regenerative medicine

    Science.gov (United States)

    Although a 'vascular stem cell' population has not been identified or generated, vascular endothelial and mural cells (smooth muscle cells and pericytes) can be derived from currently known pluripotent stem cell sources, including human embryonic stem cells and induced pluripotent stem cells. We rev...

  16. Transforming growth factor β family members in regulation of vascular function: in the light of vascular conditional knockouts.

    Science.gov (United States)

    Jakobsson, Lars; van Meeteren, Laurens A

    2013-05-15

    Blood vessels are composed of endothelial cells, mural cells (smooth muscle cells and pericytes) and their shared basement membrane. During embryonic development a multitude of signaling components orchestrate the formation of new vessels. The process is highly dependent on correct dosage, spacing and timing of these signaling molecules. As vessels mature some cascades remain active, albeit at very low levels, and may be reactivated upon demand. Members of the Transforming growth factor β (TGF-β) protein family are strongly engaged in developmental angiogenesis but are also regulators of vascular integrity in the adult. In humans various genetic alterations within this protein family cause vascular disorders, involving disintegration of vascular integrity. Here we summarize and discuss recent data gathered from conditional and endothelial cell specific genetic loss-of-function of members of the TGF-β family in the mouse. Copyright © 2013 Elsevier Inc. All rights reserved.

  17. Vascular Wall-Resident Multipotent Stem Cells of Mesenchymal Nature within the Process of Vascular Remodeling: Cellular Basis, Clinical Relevance, and Implications for Stem Cell Therapy.

    Science.gov (United States)

    Klein, Diana

    2016-01-01

    Until some years ago, the bone marrow and the endothelial cell compartment lining the vessel lumen (subendothelial space) were thought to be the only sources providing vascular progenitor cells. Now, the vessel wall, in particular, the vascular adventitia, has been established as a niche for different types of stem and progenitor cells with the capacity to differentiate into both vascular and nonvascular cells. Herein, vascular wall-resident multipotent stem cells of mesenchymal nature (VW-MPSCs) have gained importance because of their large range of differentiation in combination with their distribution throughout the postnatal organism which is related to their existence in the adventitial niche, respectively. In general, mesenchymal stem cells, also designated as mesenchymal stromal cells (MSCs), contribute to the maintenance of organ integrity by their ability to replace defunct cells or secrete cytokines locally and thus support repair and healing processes of the affected tissues. This review will focus on the central role of VW-MPSCs within vascular reconstructing processes (vascular remodeling) which are absolute prerequisite to preserve the sensitive relationship between resilience and stability of the vessel wall. Further, a particular advantage for the therapeutic application of VW-MPSCs for improving vascular function or preventing vascular damage will be discussed.

  18. Vascular endothelial growth factor signaling is necessary for expansion of medullary microvessels during postnatal kidney development

    DEFF Research Database (Denmark)

    Robdrup Tinning, Anne; Jensen, Boye L; Johnsen, Iben

    2016-01-01

    Postnatal inhibition or deletion of angiotensin II (ANG II) AT1 receptors impairs renal medullary mircrovascular development through a mechanism that may include vascular endothelial growth factor (VEGF). The present study was designed to test if VEGF/VEGF receptor signaling is necessary....... In human fetal kidney tissue, immature vascular bundles appeared early in the third trimester (GA27-28) and expanded in size until term. Rat pups treated with the VEGF receptor-2 (VEGFR2) inhibitor vandetanib (100 mg·kg(-1)·day(-1)) from P7 to P12 or P10 to P16 displayed growth retardation and proteinuria...... for the development of the renal medullary microcirculation. Endothelial cell-specific immunolabeling of kidney sections from rats showed immature vascular bundles at postnatal day (P) 10 with subsequent expansion of bundles until P21. Medullary VEGF protein abundance coincided with vasa recta bundle formation...

  19. Toll-Like Receptor 9-Dependent AMPKα Activation Occurs via TAK1 and Contributes to RhoA/ROCK Signaling and Actin Polymerization in Vascular Smooth Muscle Cells.

    Science.gov (United States)

    McCarthy, Cameron G; Wenceslau, Camilla F; Ogbi, Safia; Szasz, Theodora; Webb, R Clinton

    2018-04-01

    Traditionally, Toll-like receptor 9 (TLR9) signals through an MyD88-dependent cascade that results in proinflammatory gene transcription. Recently, it was reported that TLR9 also participates in a stress tolerance signaling cascade in nonimmune cells. In this noncanonical pathway, TLR9 binds to and inhibits sarcoplasmic/endoplasmic reticulum Ca 2+ -ATPase 2 (SERCA2), modulating intracellular calcium handling, and subsequently resulting in the activation of 5'-AMP-activated protein kinase α (AMPK α ). We have previously reported that TLR9 causes increased contraction in isolated arteries; however, the mechanisms underlying this vascular dysfunction need to be further clarified. Therefore, we hypothesized that noncanonical TLR9 signaling was also present in vascular smooth muscle cells (VSMCs) and that it mediates enhanced contractile responses through SERCA2 inhibition. To test these hypotheses, aortic microsomes, aortic VSMCs, and isolated arteries from male Sprague-Dawley rats were incubated with vehicle or TLR9 agonist (ODN2395). Despite clear AMPK α activation after treatment with ODN2395, SERCA2 activity was unaffected. Alternatively, ODN2395 caused the phosphorylation of AMPK α via transforming growth factor β -activated kinase 1 (TAK1), a kinase involved in TLR9 inflammatory signaling. Downstream, we hypothesized that that TLR9 activation of AMPK α may be important in mediating actin cytoskeleton reorganization. ODN2395 significantly increased the filamentous-to-globular actin ratio, as well as indices of RhoA/Rho-associated protein kinase (ROCK) activation, with the latter being prevented by AMPK α inhibition. In conclusion, AMPK α phosphorylation after TLR9 activation in VSMCs appears to be an extension of traditional inflammatory signaling via TAK1, as opposed to SERCA2 inhibition and the noncanonical pathway. Nonetheless, TLR9-AMPK α signaling can mediate VSMC function via RhoA/ROCK activation and actin polymerization. Copyright © 2018 by The

  20. T cells in vascular inflammatory diseases

    Directory of Open Access Journals (Sweden)

    Lucas L Lintermans

    2014-10-01

    Full Text Available Inflammation of the human vasculature is a manifestation of many different diseases ranging from systemic autoimmune diseases to chronic inflammatory diseases, in which multiple types of immune cells are involved. For both autoimmune diseases and chronic inflammatory diseases several observations support a key role for T lymphocytes in these disease pathologies, but the underlying mechanisms are poorly understood. Previous studies in several autoimmune diseases have demonstrated a significant role for a specific subset of CD4+ T cells termed effector memory T cells. This expanded population of effector memory T cells may contribute to tissue injury and disease progression. These cells exert multiple pro-inflammatory functions through the release of effector cytokines. Many of these cytokines have been detected in the inflammatory lesions and participate in the vasculitic reaction, contributing to recruitment of macrophages, neutrophils, dendritic cells, NK cells, B cells and T cells. In addition, functional impairment of regulatory T cells paralyzes anti-inflammatory effects in vasculitic disorders. Interestingly, activation of effector memory T cells in uniquely dependent on the voltage-gated Kv1.3 potassium channel providing an anchor for specific drug targeting. In this review, we focus on the CD4+ T cells in the context of vascular inflammation and describe the evidence supporting the role of different T cell subsets in vascular inflammation. Selective targeting of pathogenic effector memory T cells might enable a more tailored therapeutic approach that avoids unwanted adverse side effects of generalized immunosuppression by modulating the effector functions of T cell responses to inhibit the development of vascular inflammation.

  1. Abnormalities of Gq-mediated cell signaling in Bartter and Gitelman syndromes.

    NARCIS (Netherlands)

    Calo, L.; Ceolotto, G.; Milani, M.; Pagnin, E.; Heuvel, L.P.W.J. van den; Sartori, M.; Davis, A.P.; Costa, R.; Semplicini, A.

    2001-01-01

    BACKGROUND: The constitutive endothelial isoform of nitric oxide synthase (ecNOS) and nitric oxide (NO) production are increased in patients with Bartter syndrome (BS) and Gitelman (GS) syndrome and may reduce vascular tone. Moreover, these patients present an abnormal cell signaling [reduced

  2. FGF-dependent metabolic control of vascular development

    Science.gov (United States)

    Yu, Pengchun; Alves, Tiago C.; Fang, Jennifer S.; Xie, Yi; Zhu, Jie; Chen, Zehua; De Smet, Frederik; Zhang, Jiasheng; Jin, Suk-Won; Sun, Lele; Sun, Hongye; Kibbey, Richard G.; Hirschi, Karen K.; Hay, Nissim; Carmeliet, Peter; Chittenden, Thomas W.; Eichmann, Anne; Potente, Michael; Simons, Michael

    2017-01-01

    Blood and lymphatic vasculatures are intimately involved in tissue oxygenation and fluid homeostasis maintenance. Assembly of these vascular networks involves sprouting, migration and proliferation of endothelial cells. Recent studies have suggested that changes in cellular metabolism are of importance to these processes1. While much is known about vascular endothelial growth factor (VEGF)-dependent regulation of vascular development and metabolism2,3, little is understood about the role of fibroblast growth factors (FGFs) in this context4. Here we identify FGF receptor (FGFR) signaling as a critical regulator of vascular development. This is achieved by FGF-dependent control of c-MYC (MYC) expression that, in turn, regulates expression of the glycolytic enzyme hexokinase 2 (HK2). A decrease in HK2 levels in the absence of FGF signaling inputs results in decreased glycolysis leading to impaired endothelial cell proliferation and migration. Pan-endothelial- and lymphatic-specific Hk2 knockouts phenocopy blood and/or lymphatic vascular defects seen in Fgfr1/r3 double mutant mice while HK2 overexpression partially rescues the defects caused by suppression of FGF signaling. Thus, FGF-dependent regulation of endothelial glycolysis is a pivotal process in developmental and adult vascular growth and development. PMID:28467822

  3. Redundant control of migration and adhesion by ERM proteins in vascular smooth muscle cells

    International Nuclear Information System (INIS)

    Baeyens, Nicolas; Latrache, Iman; Yerna, Xavier; Noppe, Gauthier; Horman, Sandrine; Morel, Nicole

    2013-01-01

    Highlights: •The three ERM proteins are expressed in vascular smooth muscle cell. •ERM depletion inhibited PDGF-evoked migration redundantly. •ERM depletion increased cell adhesion redundantly. •ERM depletion did not affect PDGF-evoked Ca signal, Rac1 activation, proliferation. •ERM proteins control PDGF-induced migration by regulating adhesion. -- Abstract: Ezrin, radixin, and moesin possess a very similar structure with a C-terminal actin-binding domain and a N-terminal FERM interacting domain. They are known to be involved in cytoskeleton organization in several cell types but their function in vascular smooth muscle cells (VSMC) is still unknown. The aim of this study was to investigate the role of ERM proteins in cell migration induced by PDGF, a growth factor involved in pathophysiological processes like angiogenesis or atherosclerosis. We used primary cultured VSMC obtained from rat aorta, which express the three ERM proteins. Simultaneous depletion of the three ERM proteins with specific siRNAs abolished the effects of PDGF on cell architecture and migration and markedly increased cell adhesion and focal adhesion size, while these parameters were only slightly affected by depletion of ezrin, radixin or moesin alone. Rac1 activation, cell proliferation, and Ca 2+ signal in response to PDGF were unaffected by ERM depletion. These results indicate that ERM proteins exert a redundant control on PDGF-induced VSMC migration by regulating focal adhesion turn-over and cell adhesion to substrate

  4. Redundant control of migration and adhesion by ERM proteins in vascular smooth muscle cells

    Energy Technology Data Exchange (ETDEWEB)

    Baeyens, Nicolas; Latrache, Iman; Yerna, Xavier [Laboratory of Cell Physiology, IoNS, Université Catholique de Louvain (Belgium); Noppe, Gauthier; Horman, Sandrine [Pôle de Recherche Cardiovasculaire, IREC, Université Catholique de Louvain (Belgium); Morel, Nicole, E-mail: nicole.morel@uclouvain.be [Laboratory of Cell Physiology, IoNS, Université Catholique de Louvain (Belgium)

    2013-11-22

    Highlights: •The three ERM proteins are expressed in vascular smooth muscle cell. •ERM depletion inhibited PDGF-evoked migration redundantly. •ERM depletion increased cell adhesion redundantly. •ERM depletion did not affect PDGF-evoked Ca signal, Rac1 activation, proliferation. •ERM proteins control PDGF-induced migration by regulating adhesion. -- Abstract: Ezrin, radixin, and moesin possess a very similar structure with a C-terminal actin-binding domain and a N-terminal FERM interacting domain. They are known to be involved in cytoskeleton organization in several cell types but their function in vascular smooth muscle cells (VSMC) is still unknown. The aim of this study was to investigate the role of ERM proteins in cell migration induced by PDGF, a growth factor involved in pathophysiological processes like angiogenesis or atherosclerosis. We used primary cultured VSMC obtained from rat aorta, which express the three ERM proteins. Simultaneous depletion of the three ERM proteins with specific siRNAs abolished the effects of PDGF on cell architecture and migration and markedly increased cell adhesion and focal adhesion size, while these parameters were only slightly affected by depletion of ezrin, radixin or moesin alone. Rac1 activation, cell proliferation, and Ca{sup 2+} signal in response to PDGF were unaffected by ERM depletion. These results indicate that ERM proteins exert a redundant control on PDGF-induced VSMC migration by regulating focal adhesion turn-over and cell adhesion to substrate.

  5. Gallic acid inhibits vascular calcification through the blockade of BMP2-Smad1/5/8 signaling pathway.

    Science.gov (United States)

    Kee, Hae Jin; Cho, Soo-Na; Kim, Gwi Ran; Choi, Sin Young; Ryu, Yuhee; Kim, In Kyeom; Hong, Young Joon; Park, Hyung Wook; Ahn, Youngkeun; Cho, Jeong Gwan; Park, Jong Chun; Jeong, Myung Ho

    2014-11-01

    Vascular calcification is associated with increased risk of morbidity and mortality in patients with cardiovascular diseases, chronic kidney diseases, and diabetes. Gallic acid, a natural compound found in gallnut and green tea, is known to be antifungal, antioxidant, and anticancer. Here we investigated the effect of gallic acid on vascular smooth muscle cell (VSMC) calcification and the underlying mechanism. Gallic acid inhibited inorganic phosphate-induced osteoblast differentiation markers as well as calcification phenotypes (as determined by calcium deposition, Alizarin Red, and Von Kossa staining). Knockdown of BMP2 or Noggin blocked phosphate-induced calcification. Gallic acid suppressed phosphorylation of Smad1/5/8 protein induced by inorganic phosphate. Taken together, we suggest that gallic acid acts as a novel therapeutic agent of vascular calcification by mediating BMP2-Smad1/5/8 signaling pathway. Copyright © 2014 Elsevier Inc. All rights reserved.

  6. IGF-1 has plaque-stabilizing effects in atherosclerosis by altering vascular smooth muscle cell phenotype

    NARCIS (Netherlands)

    von der Thüsen, Jan H.; Borensztajn, Keren S.; Moimas, Silvia; van Heiningen, Sandra; Teeling, Peter; van Berkel, Theo J. C.; Biessen, Erik A. L.

    2011-01-01

    Insulin-like growth factor-1 (IGF-1) signaling is important for the maintenance of plaque stability in atherosclerosis due to its effects on vascular smooth muscle cell (vSMC) phenotype. To investigate this hypothesis, we studied the effects of the highly inflammatory milieu of the atherosclerotic

  7. Cell proliferation along vascular islands during microvascular network growth

    Directory of Open Access Journals (Sweden)

    Kelly-Goss Molly R

    2012-06-01

    Full Text Available Abstract Background Observations in our laboratory provide evidence of vascular islands, defined as disconnected endothelial cell segments, in the adult microcirculation. The objective of this study was to determine if vascular islands are involved in angiogenesis during microvascular network growth. Results Mesenteric tissues, which allow visualization of entire microvascular networks at a single cell level, were harvested from unstimulated adult male Wistar rats and Wistar rats 3 and 10 days post angiogenesis stimulation by mast cell degranulation with compound 48/80. Tissues were immunolabeled for PECAM and BRDU. Identification of vessel lumens via injection of FITC-dextran confirmed that endothelial cell segments were disconnected from nearby patent networks. Stimulated networks displayed increases in vascular area, length density, and capillary sprouting. On day 3, the percentage of islands with at least one BRDU-positive cell increased compared to the unstimulated level and was equal to the percentage of capillary sprouts with at least one BRDU-positive cell. At day 10, the number of vascular islands per vascular area dramatically decreased compared to unstimulated and day 3 levels. Conclusions These results show that vascular islands have the ability to proliferate and suggest that they are able to incorporate into the microcirculation during the initial stages of microvascular network growth.

  8. Specialized mouse embryonic stem cells for studying vascular development.

    Science.gov (United States)

    Glaser, Drew E; Burns, Andrew B; Hatano, Rachel; Medrzycki, Magdalena; Fan, Yuhong; McCloskey, Kara E

    2014-01-01

    Vascular progenitor cells are desirable in a variety of therapeutic strategies; however, the lineage commitment of endothelial and smooth muscle cell from a common progenitor is not well-understood. Here, we report the generation of the first dual reporter mouse embryonic stem cell (mESC) lines designed to facilitate the study of vascular endothelial and smooth muscle development in vitro. These mESC lines express green fluorescent protein (GFP) under the endothelial promoter, Tie-2, and Discomsoma sp. red fluorescent protein (RFP) under the promoter for alpha-smooth muscle actin (α-SMA). The lines were then characterized for morphology, marker expression, and pluripotency. The mESC colonies were found to exhibit dome-shaped morphology, alkaline phosphotase activity, as well as expression of Oct 3/4 and stage-specific embryonic antigen-1. The mESC colonies were also found to display normal karyotypes and are able to generate cells from all three germ layers, verifying pluripotency. Tissue staining confirmed the coexpression of VE (vascular endothelial)-cadherin with the Tie-2 GFP+ expression on endothelial structures and smooth muscle myosin heavy chain with the α-SMA RFP+ smooth muscle cells. Lastly, it was verified that the developing mESC do express Tie-2 GFP+ and α-SMA RFP+ cells during differentiation and that the GFP+ cells colocalize with the vascular-like structures surrounded by α-SMA-RFP cells. These dual reporter vascular-specific mESC permit visualization and cell tracking of individual endothelial and smooth muscle cells over time and in multiple dimensions, a powerful new tool for studying vascular development in real time.

  9. Selective Deletion of Leptin Signaling in Endothelial Cells Enhances Neointima Formation and Phenocopies the Vascular Effects of Diet-Induced Obesity in Mice.

    Science.gov (United States)

    Hubert, Astrid; Bochenek, Magdalena L; Schütz, Eva; Gogiraju, Rajinikanth; Münzel, Thomas; Schäfer, Katrin

    2017-09-01

    Obesity is associated with elevated circulating leptin levels and hypothalamic leptin resistance. Leptin receptors (LepRs) are expressed on endothelial cells, and leptin promotes neointima formation in a receptor-dependent manner. Our aim was to examine the importance of endothelial LepR (End.LepR) signaling during vascular remodeling and to determine whether the cardiovascular consequences of obesity are because of hyperleptinemia or endothelial leptin resistance. Mice with loxP-flanked LepR alleles were mated with mice expressing Cre recombinase controlled by the inducible endothelial receptor tyrosine kinase promoter. Obesity was induced with high-fat diet. Neointima formation was examined after chemical carotid artery injury. Morphometric quantification revealed significantly greater intimal hyperplasia, neointimal cellularity, and proliferation in End.LepR knockout mice, and similar findings were obtained in obese, hyperleptinemic End.LepR wild-type animals. Analysis of primary endothelial cells confirmed abrogated signal transducer and activator of transcription-3 phosphorylation in response to leptin in LepR knockout and obese LepR wild-type mice. Quantitative PCR, ELISA, and immunofluorescence analyses revealed increased expression and release of endothelin-1 in End.LepR-deficient and LepR-resistant cells, and ET receptor A/B antagonists abrogated their paracrine effects on murine aortic smooth muscle cell proliferation. Reduced expression of peroxisome proliferator-activated receptor-γ and increased nuclear activator protein-1 staining was observed in End.LepR-deficient and LepR-resistant cells, and peroxisome proliferator-activated receptor-γ antagonization increased endothelial endothelin-1 expression. Our findings suggest that intact endothelial leptin signaling limits neointima formation and that obesity represents a state of endothelial leptin resistance. These observations and the identification of endothelin-1 as soluble mediator of the

  10. [Vascular Calcification - Pathological Mechanism and Clinical Application - . Role of vascular smooth muscle cells in vascular calcification].

    Science.gov (United States)

    Kurabayashi, Masahiko

    2015-05-01

    Vascular calcification is commonly seen with aging, chronic kidney disese (CKD), diabetes, and atherosclerosis, and is closely associated with cardiovascular morbidity and mortality. Vascular calcification has long been regarded as the final stage of degeneration and necrosis of arterial wall and a passive, unregulated process. However, it is now known to be an active and tightly regulated process involved with phenotypic transition of vascular smooth muscle cells (VSMC) that resembles bone mineralization. Briefly, calcium deposits of atherosclerotic plaque consist of hydroxyapatite and may appear identical to fully formed lamellar bone. By using a genetic fate mapping strategy, VSMC of the vascular media give rise to the majority of the osteochondrogenic precursor- and chondrocyte-like cells observed in the calcified arterial media of MGP (- / -) mice. Osteogenic differentiation of VSMC is characterized by the expression of bone-related molecules including bone morphogenetic protein (BMP) -2, Msx2 and osteopontin, which are produced by osteoblasts and chondrocytes. Our recent findings are that (i) Runx2 and Notch1 induce osteogenic differentiation, and (ii) advanced glycation end-product (AGE) /receptor for AGE (RAGE) and palmitic acid promote osteogenic differentiation of VSMC. To understand of the molecular mechanisms of vascular calcification is now under intensive research area.

  11. Microparticle Shedding from Neural Progenitor Cells and Vascular Compartment Cells Is Increased in Ischemic Stroke.

    Science.gov (United States)

    Chiva-Blanch, Gemma; Suades, Rosa; Crespo, Javier; Peña, Esther; Padró, Teresa; Jiménez-Xarrié, Elena; Martí-Fàbregas, Joan; Badimon, Lina

    2016-01-01

    Ischemic stroke has shown to induce platelet and endothelial microparticle shedding, but whether stroke induces microparticle shedding from additional blood and vascular compartment cells is unclear. Neural precursor cells have been shown to replace dying neurons at sites of brain injury; however, if neural precursor cell activation is associated to microparticle shedding, and whether this activation is maintained at long term and associates to stroke type and severity remains unknown. We analyzed neural precursor cells and blood and vascular compartment cells microparticle shedding after an acute ischemic stroke. Forty-four patients were included in the study within the first 48h after the onset of stroke. The cerebral lesion size was evaluated at 3-7 days of the stroke. Circulating microparticles from neural precursor cells and blood and vascular compartment cells (platelets, endothelial cells, erythrocytes, leukocytes, lymphocytes, monocytes and smooth muscle cells) were analyzed by flow cytometry at the onset of stroke and at 7 and 90 days. Forty-four age-matched high cardiovascular risk subjects without documented vascular disease were used as controls. Compared to high cardiovascular risk controls, patients showed higher number of neural precursor cell- and all blood and vascular compartment cell-derived microparticles at the onset of stroke, and after 7 and 90 days. At 90 days, neural precursor cell-derived microparticles decreased and smooth muscle cell-derived microparticles increased compared to levels at the onset of stroke, but only in those patients with the highest stroke-induced cerebral lesions. Stroke increases blood and vascular compartment cell and neural precursor cell microparticle shedding, an effect that is chronically maintained up to 90 days after the ischemic event. These results show that stroke induces a generalized blood and vascular cell activation and the initiation of neuronal cell repair process after stroke. Larger cerebral lesions

  12. Microparticle Shedding from Neural Progenitor Cells and Vascular Compartment Cells Is Increased in Ischemic Stroke.

    Directory of Open Access Journals (Sweden)

    Gemma Chiva-Blanch

    Full Text Available Ischemic stroke has shown to induce platelet and endothelial microparticle shedding, but whether stroke induces microparticle shedding from additional blood and vascular compartment cells is unclear. Neural precursor cells have been shown to replace dying neurons at sites of brain injury; however, if neural precursor cell activation is associated to microparticle shedding, and whether this activation is maintained at long term and associates to stroke type and severity remains unknown. We analyzed neural precursor cells and blood and vascular compartment cells microparticle shedding after an acute ischemic stroke.Forty-four patients were included in the study within the first 48h after the onset of stroke. The cerebral lesion size was evaluated at 3-7 days of the stroke. Circulating microparticles from neural precursor cells and blood and vascular compartment cells (platelets, endothelial cells, erythrocytes, leukocytes, lymphocytes, monocytes and smooth muscle cells were analyzed by flow cytometry at the onset of stroke and at 7 and 90 days. Forty-four age-matched high cardiovascular risk subjects without documented vascular disease were used as controls.Compared to high cardiovascular risk controls, patients showed higher number of neural precursor cell- and all blood and vascular compartment cell-derived microparticles at the onset of stroke, and after 7 and 90 days. At 90 days, neural precursor cell-derived microparticles decreased and smooth muscle cell-derived microparticles increased compared to levels at the onset of stroke, but only in those patients with the highest stroke-induced cerebral lesions.Stroke increases blood and vascular compartment cell and neural precursor cell microparticle shedding, an effect that is chronically maintained up to 90 days after the ischemic event. These results show that stroke induces a generalized blood and vascular cell activation and the initiation of neuronal cell repair process after stroke. Larger

  13. Implication of molecular vascular smooth muscle cell heterogeneity among arterial beds in arterial calcification.

    Directory of Open Access Journals (Sweden)

    Olivier Espitia

    Full Text Available Vascular calcification is a strong and independent predictive factor for cardiovascular complications and mortality. Our previous work identified important discrepancies in plaque composition and calcification types between carotid and femoral arteries. The objective of this study is to further characterize and understand the heterogeneity in vascular calcification among vascular beds, and to identify molecular mechanisms underlying this process. We established ECLAGEN biocollection that encompasses human atherosclerotic lesions and healthy arteries from different locations (abdominal, thoracic aorta, carotid, femoral, and infrapopliteal arteries for histological, cell isolation, and transcriptomic analysis. Our results show that lesion composition differs between these locations. Femoral arteries are the most calcified arteries overall. They develop denser calcifications (sheet-like, nodule, and are highly susceptible to osteoid metaplasia. These discrepancies may derive from intrinsic differences between SMCs originating from these locations, as microarray analysis showed specific transcriptomic profiles between primary SMCs isolated from each arterial bed. These molecular differences translated into functional disparities. SMC from femoral arteries showed the highest propensity to mineralize due to an increase in basal TGFβ signaling. Our results suggest that biological heterogeneity of resident vascular cells between arterial beds, reflected by our transcriptomic analysis, is critical in understanding plaque biology and calcification, and may have strong implications in vascular therapeutic approaches.

  14. A genetic screen for vascular mutants in zebrafish reveals dynamic roles for Vegf/Plcg1 signaling during artery development.

    Science.gov (United States)

    Covassin, L D; Siekmann, A F; Kacergis, M C; Laver, E; Moore, J C; Villefranc, J A; Weinstein, B M; Lawson, N D

    2009-05-15

    In this work we describe a forward genetic approach to identify mutations that affect blood vessel development in the zebrafish. By applying a haploid screening strategy in a transgenic background that allows direct visualization of blood vessels, it was possible to identify several classes of mutant vascular phenotypes. Subsequent characterization of mutant lines revealed that defects in Vascular endothelial growth factor (Vegf) signaling specifically affected artery development. Comparison of phenotypes associated with different mutations within a functional zebrafish Vegf receptor-2 ortholog (referred to as kdr-like, kdrl) revealed surprisingly varied effects on vascular development. In parallel, we identified an allelic series of mutations in phospholipase c gamma 1 (plcg1). Together with in vivo structure-function analysis, our results suggest a requirement for Plcg1 catalytic activity downstream of receptor tyrosine kinases. We further find that embryos lacking both maternal and zygotic plcg1 display more severe defects in artery differentiation but are otherwise similar to zygotic mutants. Finally, we demonstrate through mosaic analysis that plcg1 functions autonomously in endothelial cells. Together our genetic analyses suggest that Vegf/Plcg1 signaling acts at multiple time points and in different signaling contexts to mediate distinct aspects of artery development.

  15. Cell sheet engineering using the stromal vascular fraction of adipose tissue as a vascularization strategy

    OpenAIRE

    Costa, M.; Cerqueira, Mariana Teixeira; Santos, T. C.; Marques, Belém Sampaio; Ludovico, Paula; Marques, A. P.; Pirraco, Rogério P.; Reis, R. L.

    2017-01-01

    Current vascularization strategies for Tissue Engineering constructs, in particular cell sheet-based, are limited by time-consuming and expensive endothelial cell isolation and/or by the complexity of using extrinsic growth factors. Herein, we propose an alternative strategy using angiogenic cell sheets (CS) obtained from the stromal vascular fraction (SVF) of adipose tissue that can be incorporated into more complex constructs. Cells from the SVF were cultured in normoxic and hypoxic conditi...

  16. Vascular endothelial growth factor signaling regulates the segregation of artery and vein via ERK activity during vascular development

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Se-Hee [McAllister Heart Institute, Curriculum in Genetics and Molecular Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599 (United States); Schmitt, Christopher E.; Woolls, Melissa J. [McAllister Heart Institute, Curriculum in Genetics and Molecular Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599 (United States); Yale Cardiovascular Research Center and Section of Cardiovascular Medicine, Dept. of Internal Medicine, Yale University School of Medicine, New Haven, CT 06511 (United States); Holland, Melinda B. [McAllister Heart Institute, Curriculum in Genetics and Molecular Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599 (United States); Kim, Jun-Dae [Yale Cardiovascular Research Center and Section of Cardiovascular Medicine, Dept. of Internal Medicine, Yale University School of Medicine, New Haven, CT 06511 (United States); Jin, Suk-Won, E-mail: suk-won.jin@yale.edu [Yale Cardiovascular Research Center and Section of Cardiovascular Medicine, Dept. of Internal Medicine, Yale University School of Medicine, New Haven, CT 06511 (United States)

    2013-01-25

    Highlights: ► VEGF-A signaling regulates the segregation of axial vessels. ► VEGF-A signaling is mediated by PKC and ERK in this process. ► Ectopic activation of ERK is sufficient to rescue defects in vessel segregation. -- Abstract: Segregation of two axial vessels, the dorsal aorta and caudal vein, is one of the earliest patterning events occur during development of vasculature. Despite the importance of this process and recent advances in our understanding on vascular patterning during development, molecular mechanisms that coordinate the segregation of axial vessels remain largely elusive. In this report, we find that vascular endothelial growth factor-A (Vegf-A) signaling regulates the segregation of dorsal aorta and axial vein during development. Inhibition of Vegf-A pathway components including ligand Vegf-A and its cognate receptor Kdrl, caused failure in segregation of axial vessels in zebrafish embryos. Similarly, chemical inhibition of Mitogen-activated protein kinase kinase (Map2k1)/Extracellular-signal-regulated kinases (Erk) and phosphatidylinositol 3-kinases (PI3 K), which are downstream effectors of Vegf-A signaling pathway, led to the fusion of two axial vessels. Moreover, we find that restoring Erk activity by over-expression of constitutively active MEK in embryos with a reduced level of Vegf-A signaling can rescue the defects in axial vessel segregation. Taken together, our data show that segregation of axial vessels requires the function of Vegf-A signaling, and Erk may function as the major downstream effector in this process.

  17. Vascular endothelial growth factor signaling regulates the segregation of artery and vein via ERK activity during vascular development

    International Nuclear Information System (INIS)

    Kim, Se-Hee; Schmitt, Christopher E.; Woolls, Melissa J.; Holland, Melinda B.; Kim, Jun-Dae; Jin, Suk-Won

    2013-01-01

    Highlights: ► VEGF-A signaling regulates the segregation of axial vessels. ► VEGF-A signaling is mediated by PKC and ERK in this process. ► Ectopic activation of ERK is sufficient to rescue defects in vessel segregation. -- Abstract: Segregation of two axial vessels, the dorsal aorta and caudal vein, is one of the earliest patterning events occur during development of vasculature. Despite the importance of this process and recent advances in our understanding on vascular patterning during development, molecular mechanisms that coordinate the segregation of axial vessels remain largely elusive. In this report, we find that vascular endothelial growth factor-A (Vegf-A) signaling regulates the segregation of dorsal aorta and axial vein during development. Inhibition of Vegf-A pathway components including ligand Vegf-A and its cognate receptor Kdrl, caused failure in segregation of axial vessels in zebrafish embryos. Similarly, chemical inhibition of Mitogen-activated protein kinase kinase (Map2k1)/Extracellular-signal-regulated kinases (Erk) and phosphatidylinositol 3-kinases (PI3 K), which are downstream effectors of Vegf-A signaling pathway, led to the fusion of two axial vessels. Moreover, we find that restoring Erk activity by over-expression of constitutively active MEK in embryos with a reduced level of Vegf-A signaling can rescue the defects in axial vessel segregation. Taken together, our data show that segregation of axial vessels requires the function of Vegf-A signaling, and Erk may function as the major downstream effector in this process

  18. Activated Fps/Fes partially rescues the in vivo developmental potential of Flk1-deficient vascular progenitor cells.

    Science.gov (United States)

    Haigh, Jody J; Ema, Masatsugu; Haigh, Katharina; Gertsenstein, Marina; Greer, Peter; Rossant, Janet; Nagy, Andras; Wagner, Erwin F

    2004-02-01

    Relatively little is known about the modulators of the vascular endothelial growth factor A (VEGF-A)/Flk1 signaling cascade. To functionally characterize this pathway, VEGF-A stimulation of endothelial cells was performed. VEGF-A-mediated Flk1 activation resulted in increased translocation of the endogenous Fps/Fes cytoplasmic tyrosine kinase to the plasma membrane and increased tyrosine phosphorylation, suggesting a role for Fps/Fes in VEGF-A/Flk1 signaling events. Addition of a myristoylation consensus sequence to Fps/Fes resulted in VEGF-A-independent membrane localization of Fps/Fes in endothelial cells. Expression of the activated Fps/Fes protein in Flk1-deficient embryonic stem (ES) cells rescued their contribution to the developing vascular endothelium in vivo by using ES cell-derived chimeras. Activated Fps/Fes contributed to this rescue event by restoring the migratory potential to Flk1 null progenitors, which is required for movement of hemangioblasts from the primitive streak region into the yolk sac proper. Activated Fps/Fes in the presence of Flk1 increased the number of hemangioblast colonies in vitro and increased the number of mesodermal progenitors in vivo. These results suggest that Fps/Fes may act synergistically with Flk1 to modulate hemangioblast differentiation into the endothelium. We have also demonstrated that activated Fps/Fes causes hemangioma formation in vivo, independently of Flk1, as a result of increasing vascular progenitor density.

  19. The skeletal vascular system - Breathing life into bone tissue.

    Science.gov (United States)

    Stegen, Steve; Carmeliet, Geert

    2017-08-26

    During bone development, homeostasis and repair, a dense vascular system provides oxygen and nutrients to highly anabolic skeletal cells. Characteristic for the vascular system in bone is the serial organization of two capillary systems, each typified by specific morphological and physiological features. Especially the arterial capillaries mediate the growth of the bone vascular system, serve as a niche for skeletal and hematopoietic progenitors and couple angiogenesis to osteogenesis. Endothelial cells and osteoprogenitor cells interact not only physically, but also communicate to each other by secretion of growth factors. A vital angiogenic growth factor is vascular endothelial growth factor and its expression in skeletal cells is controlled by osteogenic transcription factors and hypoxia signaling, whereas the secretion of angiocrine factors by endothelial cells is regulated by Notch signaling, blood flow and possibly hypoxia. Bone loss and impaired fracture repair are often associated with reduced and disorganized blood vessel network and therapeutic targeting of the angiogenic response may contribute to enhanced bone regeneration. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Contribution of endothelial progenitors and proangiogenic hematopoietic cells to vascularization of tumor and ischemic tissue

    Science.gov (United States)

    Kopp, Hans-Georg; Ramos, Carlos A.; Rafii, Shahin

    2010-01-01

    Purpose of review During the last several years, a substantial amount of evidence from animal as well as human studies has advanced our knowledge of how bone marrow derived cells contribute to neoangiogenesis. In the light of recent findings, we may have to redefine our thinking of endothelial cells as well as of perivascular mural cells. Recent findings Inflammatory hematopoietic cells, such as macrophages, have been shown to promote neoangiogenesis during tumor growth and wound healing. Dendritic cells, B lymphocytes, monocytes, and other immune cells have also been found to be recruited to neoangiogenic niches and to support neovessel formation. These findings have led to the concept that subsets of hematopoietic cells comprise proangiogenic cells that drive adult revascularization processes. While evidence of the importance of endothelial progenitor cells in adult vasculogenesis increased further, the role of these comobilized hematopoietic cells has been intensely studied in the last few years. Summary Angiogenic factors promote mobilization of vascular endothelial growth factor receptor 1-positive hematopoietic cells through matrix metalloproteinase-9 mediated release of soluble kit-ligand and recruit these proangiogenic cells to areas of hypoxia, where perivascular mural cells present stromal-derived factor 1 (CXCL-12) as an important retention signal. The same factors are possibly involved in mobilization of vascular endothelial growth factor receptor 2-positive endothelial precursors that may participate in neovessel formation. The complete characterization of mechanisms, mediators and signaling pathways involved in these processes will provide novel targets for both anti and proangiogenic therapeutic strategies. PMID:16567962

  1. Inhibition of cell migration by focal adhesion kinase: Time-dependent difference in integrin-induced signaling between endothelial and hepatoblastoma cells.

    Science.gov (United States)

    Yu, Hongchi; Gao, Min; Ma, Yunlong; Wang, Lijuan; Shen, Yang; Liu, Xiaoheng

    2018-05-01

    angiogenesis plays an important role in the development and progression of tumors, and it involves a series of signaling pathways contributing to the migration of endothelial cells for vascularization and to the invasion of cancer cells for secondary tumor formation. Among these pathways, the focal adhesion kinase (FAK) signaling cascade has been implicated in a variety of human cancers in connection with cell adhesion and migration events leading to tumor angiogenesis, metastasis and invasion. Therefore, the inhibition of FAK in endothelial and/or cancer cells is a potential target for anti‑angiogenic therapy. In the present study, a small‑molecule FAK inhibitor, 1,2,4,5-benzenetetramine tetrahydrochloride (Y15), was used to study the effects of FAK inhibition on the adhesion and migration behaviors of vascular endothelial cells (VECs) and human hepatoblastoma cells. Furthermore, the time-dependent differences in proteins associated with the integrin-mediated FAK/Rho GTPases signaling pathway within 2 h were examined. The results indicated that the inhibition of FAK significantly decreased the migration ability of VECs and human hepatoblastoma cells in a dose-dependent manner. Inhibition of FAK promoted cell detachment by decreasing the expression of focal adhesion components, and blocked cell motility by reducing the level of Rho GTPases. However, the expression of crucial proteins involved in integrin-induced signaling in two cell lines exhibited a time-dependent difference with increased duration of FAK inhibitor treatment, suggesting different mechanisms of FAK-mediated cell migration behavior. These results suggest that the mechanism underlying FAK-mediated adhesion and migration behavior differs among various cells, which is expected to provide evidence for future FAK therapy targeted against tumor angiogenesis.

  2. Angiotensin II upregulates the expression of placental growth factor in human vascular endothelial cells and smooth muscle cells

    Directory of Open Access Journals (Sweden)

    Guo Yingqiang

    2010-05-01

    Full Text Available Abstract Background Atherosclerosis is now recognized as a chronic inflammatory disease. Angiotensin II (Ang II is a critical factor in inflammatory responses, which promotes the pathogenesis of atherosclerosis. Placental growth factor (PlGF is a member of the vascular endothelial growth factor (VEGF family cytokines and is associated with inflammatory progress of atherosclerosis. However, the potential link between PlGF and Ang II has not been investigated. In the current study, whether Ang II could regulate PlGF expression, and the effect of PlGF on cell proliferation, was investigated in human vascular endothelial cells (VECs and smooth muscle cells (VSMCs. Results In growth-arrested human VECs and VSMCs, Ang II induced PlGF mRNA expression after 4 hour treatment, and peaked at 24 hours. 10-6 mol/L Ang II increased PlGF protein production after 8 hour treatment, and peaked at 24 hours. Stimulation with Ang II also induced mRNA expression of VEGF receptor-1 and -2(VEGFR-1 and -2 in these cells. The Ang II type I receptor (AT1R antagonist blocked Ang II-induced PlGF gene expression and protein production. Several intracellular signals elicited by Ang II were involved in PlGF synthesis, including activation of protein kinase C, extracellular signal-regulated kinase 1/2 (ERK1/2 and PI3-kinase. A neutralizing antibody against PlGF partially inhibited the Ang II-induced proliferation of VECs and VSMCs. However, this antibody showed little effect on the basal proliferation in these cells, whereas blocking antibody of VEGF could suppress both basal and Ang II-induced proliferation in VECs and VSMCs. Conclusion Our results showed for the first time that Ang II could induce the gene expression and protein production of PlGF in VECs and VSMCs, which might play an important role in the pathogenesis of vascular inflammation and atherosclerosis.

  3. DEPTOR regulates vascular endothelial cell activation and proinflammatory and angiogenic responses.

    Science.gov (United States)

    Bruneau, Sarah; Nakayama, Hironao; Woda, Craig B; Flynn, Evelyn A; Briscoe, David M

    2013-09-05

    The maintenance of normal tissue homeostasis and the prevention of chronic inflammatory disease are dependent on the active process of inflammation resolution. In endothelial cells (ECs), proinflammation results from the activation of intracellular signaling responses and/or the inhibition of endogenous regulatory/pro-resolution signaling networks that, to date, are poorly defined. In this study, we find that DEP domain containing mTOR interacting protein (DEPTOR) is expressed in different microvascular ECs in vitro and in vivo, and using a small interfering RNA (siRNA) knockdown approach, we find that it regulates mammalian target of rapamycin complex 1 (mTORC1), extracellular signal-regulated kinase 1/2, and signal transducer and activator of transcription 1 activation in part through independent mechanisms. Moreover, using limited gene arrays, we observed that DEPTOR regulates EC activation including mRNA expression of the T-cell chemoattractant chemokines CXCL9, CXCL10, CXCL11, CX3CL1, CCL5, and CCL20 and the adhesion molecules intercellular adhesion molecule-1 and vascular cell adhesion molecule-1 (P < .05). DEPTOR siRNA-transfected ECs also bound increased numbers of peripheral blood mononuclear cells (P < .005) and CD3+ T cells (P < .005) in adhesion assays in vitro and had increased migration and angiogenic responses in spheroid sprouting (P < .01) and wound healing (P < .01) assays. Collectively, these findings define DEPTOR as a critical upstream regulator of EC activation responses and suggest that it plays an important role in endogenous mechanisms of anti-inflammation and pro-resolution.

  4. Update on vascular endothelial Ca(2+) signalling: A tale of ion channels, pumps and transporters.

    Science.gov (United States)

    Moccia, Francesco; Berra-Romani, Roberto; Tanzi, Franco

    2012-07-26

    A monolayer of endothelial cells (ECs) lines the lumen of blood vessels and forms a multifunctional transducing organ that mediates a plethora of cardiovascular processes. The activation of ECs from as state of quiescence is, therefore, regarded among the early events leading to the onset and progression of potentially lethal diseases, such as hypertension, myocardial infarction, brain stroke, and tumor. Intracellular Ca(2+) signals have long been know to play a central role in the complex network of signaling pathways regulating the endothelial functions. Notably, recent work has outlined how any change in the pattern of expression of endothelial channels, transporters and pumps involved in the modulation of intracellular Ca(2+) levels may dramatically affect whole body homeostasis. Vascular ECs may react to both mechanical and chemical stimuli by generating a variety of intracellular Ca(2+) signals, ranging from brief, localized Ca(2+) pulses to prolonged Ca(2+) oscillations engulfing the whole cytoplasm. The well-defined spatiotemporal profile of the subcellular Ca(2+) signals elicited in ECs by specific extracellular inputs depends on the interaction between Ca(2+) releasing channels, which are located both on the plasma membrane and in a number of intracellular organelles, and Ca(2+) removing systems. The present article aims to summarize both the past and recent literature in the field to provide a clear-cut picture of our current knowledge on the molecular nature and the role played by the components of the Ca(2+) machinery in vascular ECs under both physiological and pathological conditions.

  5. Update on vascular endothelial Ca2+ signalling: A tale of ion channels, pumps and transporters

    Science.gov (United States)

    Moccia, Francesco; Berra-Romani, Roberto; Tanzi, Franco

    2012-01-01

    A monolayer of endothelial cells (ECs) lines the lumen of blood vessels and forms a multifunctional transducing organ that mediates a plethora of cardiovascular processes. The activation of ECs from as state of quiescence is, therefore, regarded among the early events leading to the onset and progression of potentially lethal diseases, such as hypertension, myocardial infarction, brain stroke, and tumor. Intracellular Ca2+ signals have long been know to play a central role in the complex network of signaling pathways regulating the endothelial functions. Notably, recent work has outlined how any change in the pattern of expression of endothelial channels, transporters and pumps involved in the modulation of intracellular Ca2+ levels may dramatically affect whole body homeostasis. Vascular ECs may react to both mechanical and chemical stimuli by generating a variety of intracellular Ca2+ signals, ranging from brief, localized Ca2+ pulses to prolonged Ca2+ oscillations engulfing the whole cytoplasm. The well-defined spatiotemporal profile of the subcellular Ca2+ signals elicited in ECs by specific extracellular inputs depends on the interaction between Ca2+ releasing channels, which are located both on the plasma membrane and in a number of intracellular organelles, and Ca2+ removing systems. The present article aims to summarize both the past and recent literature in the field to provide a clear-cut picture of our current knowledge on the molecular nature and the role played by the components of the Ca2+ machinery in vascular ECs under both physiological and pathological conditions. PMID:22905291

  6. Procyanidins Mitigate Osteoarthritis Pathogenesis by, at Least in Part, Suppressing Vascular Endothelial Growth Factor Signaling

    Directory of Open Access Journals (Sweden)

    Angela Wang

    2016-12-01

    Full Text Available Procyanidins are a family of plant metabolites that have been suggested to mitigate osteoarthritis pathogenesis in mice. However, the underlying mechanism is largely unknown. This study aimed to determine whether procyanidins mitigate traumatic injury-induced osteoarthritis (OA disease progression, and whether procyanidins exert a chondroprotective effect by, at least in part, suppressing vascular endothelial growth factor signaling. Procyanidins (extracts from pine bark, orally administered to mice subjected to surgery for destabilization of the medial meniscus, significantly slowed OA disease progression. Real-time polymerase chain reaction revealed that procyanidin treatment reduced expression of vascular endothelial growth factor and effectors in OA pathogenesis that are regulated by vascular endothelial growth factor. Procyanidin-suppressed vascular endothelial growth factor expression was correlated with reduced phosphorylation of vascular endothelial growth factor receptor 2 in human OA primary chondrocytes. Moreover, components of procyanidins, procyanidin B2 and procyanidin B3 exerted effects similar to those of total procyanidins in mitigating the OA-related gene expression profile in the primary culture of human OA chondrocytes in the presence of vascular endothelial growth factor. Together, these findings suggest procyanidins mitigate OA pathogenesis, which is mediated, at least in part, by suppressing vascular endothelial growth factor signaling.

  7. Mercury induces proliferation and reduces cell size in vascular smooth muscle cells through MAPK, oxidative stress and cyclooxygenase-2 pathways

    Energy Technology Data Exchange (ETDEWEB)

    Aguado, Andrea; Galán, María; Zhenyukh, Olha; Wiggers, Giulia A.; Roque, Fernanda R. [Departamento de Farmacología, Facultad de Medicina, Universidad Autónoma de Madrid, Instituto de Investigación Hospital Universitario La Paz (IdiPAZ), 28029, Madrid (Spain); Redondo, Santiago [Departamento de Farmacología, Facultad de Medicina, Universidad Complutense, 28040, Madrid (Spain); Peçanha, Franck [Departamento de Farmacología, Facultad de Medicina, Universidad Autónoma de Madrid, Instituto de Investigación Hospital Universitario La Paz (IdiPAZ), 28029, Madrid (Spain); Martín, Angela [Departamento de Bioquímica, Fisiología y Genética Molecular, Universidad Rey Juan Carlos, 28922, Alcorcón (Spain); Fortuño, Ana [Área de Ciencias Cardiovasculares, Centro de Investigación Médica Aplicada, Universidad de Navarra, 31008, Pamplona (Spain); Cachofeiro, Victoria [Departamento de Fisiología, Facultad de Medicina, Universidad Complutense, 28040, Madrid (Spain); Tejerina, Teresa [Departamento de Farmacología, Facultad de Medicina, Universidad Complutense, 28040, Madrid (Spain); Salaices, Mercedes, E-mail: mercedes.salaices@uam.es [Departamento de Farmacología, Facultad de Medicina, Universidad Autónoma de Madrid, Instituto de Investigación Hospital Universitario La Paz (IdiPAZ), 28029, Madrid (Spain); and others

    2013-04-15

    Mercury exposure is known to increase cardiovascular risk but the underlying cellular mechanisms remain undetermined. We analyzed whether chronic exposure to HgCl{sub 2} affects vascular structure and the functional properties of vascular smooth muscle cells (VSMC) through oxidative stress/cyclooxygenase-2 dependent pathways. Mesenteric resistance arteries and aortas from Wistar rats treated with HgCl{sub 2} (first dose 4.6 mg kg{sup −1}, subsequent doses 0.07 mg kg{sup −1} day{sup −1}, 30 days) and cultured aortic VSMC stimulated with HgCl{sub 2} (0.05–5 μg/ml) were used. Treatment of rats with HgCl{sub 2} decreased wall thickness of the resistance and conductance vasculature, increased the number of SMC within the media and decreased SMC nucleus size. In VSMCs, exposure to HgCl{sub 2}: 1) induced a proliferative response and a reduction in cell size; 2) increased superoxide anion production, NADPH oxidase activity, gene and/or protein levels of the NADPH oxidase subunit NOX-1, the EC- and Mn-superoxide dismutases and cyclooxygenase-2 (COX-2); 3) induced activation of ERK1/2 and p38 MAPK. Both antioxidants and COX-2 inhibitors normalized the proliferative response and the altered cell size induced by HgCl{sub 2}. Blockade of ERK1/2 and p38 signaling pathways abolished the HgCl{sub 2}-induced Nox1 and COX-2 expression and normalized the alterations induced by mercury in cell proliferation and size. In conclusion, long exposure of VSMC to low doses of mercury activates MAPK signaling pathways that result in activation of inflammatory proteins such as NADPH oxidase and COX-2 that in turn induce proliferation of VSMC and changes in cell size. These findings offer further evidence that mercury might be considered an environmental risk factor for cardiovascular disease. - Highlights: ► Chronic HgCl{sub 2} exposure induces vascular remodeling. ► HgCl{sub 2} induces proliferation and decreased cell size in vascular smooth muscle cells. ► HgCl{sub 2} induces

  8. Arabidopsis VASCULAR-RELATED UNKNOWN PROTEIN1 Regulates Xylem Development and Growth by a Conserved Mechanism That Modulates Hormone Signaling1[W][OPEN

    Science.gov (United States)

    Grienenberger, Etienne; Douglas, Carl J.

    2014-01-01

    Despite a strict conservation of the vascular tissues in vascular plants (tracheophytes), our understanding of the genetic basis underlying the differentiation of secondary cell wall-containing cells in the xylem of tracheophytes is still far from complete. Using coexpression analysis and phylogenetic conservation across sequenced tracheophyte genomes, we identified a number of Arabidopsis (Arabidopsis thaliana) genes of unknown function whose expression is correlated with secondary cell wall deposition. Among these, the Arabidopsis VASCULAR-RELATED UNKNOWN PROTEIN1 (VUP1) gene encodes a predicted protein of 24 kD with no annotated functional domains but containing domains that are highly conserved in tracheophytes. Here, we show that the VUP1 expression pattern, determined by promoter-β-glucuronidase reporter gene expression, is associated with vascular tissues, while vup1 loss-of-function mutants exhibit collapsed morphology of xylem vessel cells. Constitutive overexpression of VUP1 caused dramatic and pleiotropic developmental defects, including severe dwarfism, dark green leaves, reduced apical dominance, and altered photomorphogenesis, resembling brassinosteroid-deficient mutants. Constitutive overexpression of VUP homologs from multiple tracheophyte species induced similar defects. Whole-genome transcriptome analysis revealed that overexpression of VUP1 represses the expression of many brassinosteroid- and auxin-responsive genes. Additionally, deletion constructs and site-directed mutagenesis were used to identify critical domains and amino acids required for VUP1 function. Altogether, our data suggest a conserved role for VUP1 in regulating secondary wall formation during vascular development by tissue- or cell-specific modulation of hormone signaling pathways. PMID:24567189

  9. NASAs VESGEN: Systems Analysis of Vascular Phenotypes from Stress and Other Signaling Pathways Using GeneLab.

    Science.gov (United States)

    Parsons-Wingerter, Patricia A.; Weitzel, Alexander; Vyas, Ruchi J.; Murray, Matthew C.; Wyatt, Sarah E.

    2016-01-01

    One fundamental requirement shared by humans with all higher terrestrial life forms, including insect wings, higher land plants and other vertebrates, is a complex, fractally branching vascular system. NASA's VESsel GENeration Analysis (VESGEN) software maps and quantifies vascular trees, networks, and tree-network composites according to weighted physiological rules such as vessel connectivity, tapering and bifurcational branching. According to fluid dynamics, successful vascular transport requires a complex distributed system of highly regulated laminar flow. Microvascular branching rules within vertebrates, dicot leaves and the other organisms therefore display many similarities. One unifying perspective is that vascular patterning offers a useful readout that necessarily integrates complex molecular signaling pathways. VESGEN has elucidated changes in vascular pattern resulting from inflammatory, stress response, developmental and other signaling within numerous tissues and major model organisms studied for Space Biology. For a new VESGEN systems approach, we analyzed differential gene expression in leaves of Arabidopsis thaliana reported by GeneLab (GLDS-7) for spaceflight. Vascular-related changes in leaf gene expression were identified that can potentially be phenocopied by mutants in ground-based experiments. To link transcriptional, protein and other molecular change with phenotype, alterations in the Euclidean and dynamic dimensions (x,y,t) of vascular patterns for Arabidopsis leaves and other model species are being co-localized with signaling patterns of single molecular expression analyzed as information dimensions (i,j,k,...). Previously, Drosophila microarray data returned from space suggested significant changes in genes related to wing venation development that include EGF, Notch, Hedghog, Wingless and Dpp signaling. Phenotypes of increasingly abnormal ectopic wing venation in the (non-spaceflight) Drosophila wing generated by overexpression of a

  10. The cellular response to vascular endothelial growth factors requires co-ordinated signal transduction, trafficking and proteolysis.

    Science.gov (United States)

    Smith, Gina A; Fearnley, Gareth W; Tomlinson, Darren C; Harrison, Michael A; Ponnambalam, Sreenivasan

    2015-08-18

    VEGFs (vascular endothelial growth factors) are a family of conserved disulfide-linked soluble secretory glycoproteins found in higher eukaryotes. VEGFs mediate a wide range of responses in different tissues including metabolic homoeostasis, cell proliferation, migration and tubulogenesis. Such responses are initiated by VEGF binding to soluble and membrane-bound VEGFRs (VEGF receptor tyrosine kinases) and co-receptors. VEGF and receptor splice isoform diversity further enhances complexity of membrane protein assembly and function in signal transduction pathways that control multiple cellular responses. Different signal transduction pathways are simultaneously activated by VEGFR-VEGF complexes with membrane trafficking along the endosome-lysosome network further modulating signal output from multiple enzymatic events associated with such pathways. Balancing VEGFR-VEGF signal transduction with trafficking and proteolysis is essential in controlling the intensity and duration of different intracellular signalling events. Dysfunction in VEGF-regulated signal transduction is important in chronic disease states including cancer, atherosclerosis and blindness. This family of growth factors and receptors is an important model system for understanding human disease pathology and developing new therapeutics for treating such ailments. © 2015 Authors.

  11. Sphingosine-1-phosphate regulates RGS2 and RGS16 mRNA expression in vascular smooth muscle cells

    NARCIS (Netherlands)

    Hendriks-Balk, Mariëlle C.; Hajji, Najat; van Loenen, Pieter B.; Michel, Martin C.; Peters, Stephan L. M.; Alewijnse, Astrid E.

    2009-01-01

    Regulator of G protein signalling (RGS) protein expression is altered under growth promoting conditions in vascular smooth muscle cells (VSMCs). Since sphingosine-1-phosphate (S1P) is an important growth stimulatory factor, we investigated whether stimulation of VSMCs with S1P results in alterations

  12. Effect of Buddleja officinalis on high-glucose-induced vascular inflammation in human umbilical vein endothelial cells.

    Science.gov (United States)

    Lee, Yun Jung; Kang, Dae Gill; Kim, Jin Sook; Lee, Ho Sub

    2008-06-01

    In this study, we aimed to investigate whether an aqueous extract of Buddleja officinalis (ABO) suppresses high-glucose-induced vascular inflammatory processes in the primary cultured human umbilical vein endothelial cells (HUVEC). The high-glucose-induced increase in expression of cell adhesion molecules (CAMs) such as intracellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), and endothelial-selectin (E-selectin) was significantly attenuated by pretreatment with ABO in a dose-dependent manner. Enhanced cell adhesion caused by high glucose in co-cultured U937 and HUVEC was also blocked by pretreatment with ABO. Pretreatment with ABO also blocked formation of high-glucose-induced reactive oxygen species (ROS). In addition, ABO suppressed the transcriptional activity of NF-kappaB and IkappaB phosphorylation under high-glucose conditions. Pretreatment with N(G)-nitro-l-arginine methyl ester (L-NAME), an endothelial nitric oxide (NO) synthase inhibitor, attenuated the protective action of ABO on high-glucose-induced CAM expression, suggesting a potential role of NO signaling. The present data suggest that ABO could suppress high-glucose-induced vascular inflammatory processes, and ABO may be closely related with the inhibition of ROS and NF-kappaB activation in HUVEC.

  13. Insulin sensitizers prevent fine particulate matter-induced vascular insulin resistance and changes in endothelial progenitor cell homeostasis.

    Science.gov (United States)

    Haberzettl, Petra; McCracken, James P; Bhatnagar, Aruni; Conklin, Daniel J

    2016-06-01

    Exposure to fine particular matter (PM2.5) increases the risk of developing cardiovascular disease and Type 2 diabetes. Because blood vessels are sensitive targets of air pollutant exposure, we examined the effects of concentrated ambient PM2.5 (CAP) on vascular insulin sensitivity and circulating levels of endothelial progenitor cells (EPCs), which reflect cardiovascular health. We found that CAP exposure for 9 days decreased insulin-stimulated Akt phosphorylation in the aorta of mice maintained on control diet. This change was accompanied by the induction of IL-1β and increases in the abundance of cleaved IL-18 and p10 subunit of Casp-1, consistent with the activation of the inflammasome pathway. CAP exposure also suppressed circulating levels of EPCs (Flk-1(+)/Sca-1(+) cells), while enhancing the bone marrow abundance of these cells. Although similar changes in vascular insulin signaling and EPC levels were observed in mice fed high-fat diet, CAP exposure did not exacerbate diet-induced changes in vascular insulin resistance or EPC homeostasis. Treatment with an insulin sensitizer, metformin or rosiglitazone, prevented CAP-induced vascular insulin resistance and NF-κB and inflammasome activation and restored peripheral blood and bone marrow EPC levels. These findings suggest that PM2.5 exposure induces diet-independent vascular insulin resistance and inflammation and prevents EPC mobilization, and that this EPC mobilization defect could be mediated by vascular insulin resistance. Impaired vascular insulin sensitivity may be an important mechanism underlying PM2.5-induced vascular injury, and pharmacological sensitization to insulin action could potentially prevent deficits in vascular repair and mitigate vascular inflammation due to exposure to elevated levels of ambient air pollution. Copyright © 2016 the American Physiological Society.

  14. Vascular nitric oxide: Beyond eNOS

    Directory of Open Access Journals (Sweden)

    Yingzi Zhao

    2015-10-01

    Full Text Available As the first discovered gaseous signaling molecule, nitric oxide (NO affects a number of cellular processes, including those involving vascular cells. This brief review summarizes the contribution of NO to the regulation of vascular tone and its sources in the blood vessel wall. NO regulates the degree of contraction of vascular smooth muscle cells mainly by stimulating soluble guanylyl cyclase (sGC to produce cyclic guanosine monophosphate (cGMP, although cGMP-independent signaling [S-nitrosylation of target proteins, activation of sarco/endoplasmic reticulum calcium ATPase (SERCA or production of cyclic inosine monophosphate (cIMP] also can be involved. In the blood vessel wall, NO is produced mainly from l-arginine by the enzyme endothelial nitric oxide synthase (eNOS but it can also be released non-enzymatically from S-nitrosothiols or from nitrate/nitrite. Dysfunction in the production and/or the bioavailability of NO characterizes endothelial dysfunction, which is associated with cardiovascular diseases such as hypertension and atherosclerosis.

  15. Arterial spin-labeling assessment of normalized vascular intratumoral signal intensity as a predictor of histologic grade of astrocytic neoplasms.

    Science.gov (United States)

    Furtner, J; Schöpf, V; Schewzow, K; Kasprian, G; Weber, M; Woitek, R; Asenbaum, U; Preusser, M; Marosi, C; Hainfellner, J A; Widhalm, G; Wolfsberger, S; Prayer, D

    2014-03-01

    Pulsed arterial spin-labeling is a noninvasive MR imaging perfusion method performed with the use of water in the arterial blood as an endogenous contrast agent. The purpose of this study was to determine the inversion time with the largest difference in normalized intratumoral signal intensity between high-grade and low-grade astrocytomas. Thirty-three patients with gliomas, histologically classified as low-grade (n = 7) or high-grade astrocytomas (n = 26) according to the World Health Organization brain tumor classification, were included. A 3T MR scanner was used to perform pulsed arterial spin-labeling measurements at 8 different inversion times (370 ms, 614 ms, 864 ms, 1114 ms, 1364 ms, 1614 ms, 1864 ms, and 2114 ms). Normalized intratumoral signal intensity was calculated, which was defined by the signal intensity ratio of the tumor and the contralateral normal brain tissue for all fixed inversion times. A 3-way mixed ANOVA was used to reveal potential differences in the normalized vascular intratumoral signal intensity between high-grade and low-grade astrocytomas. The difference in normalized vascular intratumoral signal intensity between high-grade and low-grade astrocytomas obtained the most statistically significant results at 370 ms (P = .003, other P values ranged from .012-.955). The inversion time by which to differentiate high-grade and low-grade astrocytomas by use of normalized vascular intratumoral signal intensity was 370 ms in our study. The normalized vascular intratumoral signal intensity values at this inversion time mainly reflect the labeled intra-arterial blood bolus and therefore could be referred to as normalized vascular intratumoral signal intensity. Our data indicate that the use of normalized vascular intratumoral signal intensity values allows differentiation between low-grade and high-grade astrocytomas and thus may serve as a new, noninvasive marker for astrocytoma grading.

  16. Molecular mechanisms of maternal vascular dysfunction in preeclampsia.

    Science.gov (United States)

    Goulopoulou, Styliani; Davidge, Sandra T

    2015-02-01

    In preeclampsia, as a heterogeneous syndrome, multiple pathways have been proposed for both the causal as well as the perpetuating factors leading to maternal vascular dysfunction. Postulated mechanisms include imbalance in the bioavailability and activity of endothelium-derived contracting and relaxing factors and oxidative stress. Studies have shown that placenta-derived factors [antiangiogenic factors, microparticles (MPs), cell-free nucleic acids] are released into the maternal circulation and act on the vascular wall to modify the secretory capacity of endothelial cells and alter the responsiveness of vascular smooth muscle cells to constricting and relaxing stimuli. These molecules signal their deleterious effects on the maternal vascular wall via pathways that provide the molecular basis for novel and effective therapeutic interventions. Copyright © 2014 Elsevier Ltd. All rights reserved.

  17. The adapter protein, Grb10, is a positive regulator of vascular endothelial growth factor signaling.

    Science.gov (United States)

    Giorgetti-Peraldi, S; Murdaca, J; Mas, J C; Van Obberghen, E

    2001-07-05

    Vascular endothelial growth factor (VEGF) is an important regulator of vasculogenesis and angiogenesis. Activation of VEGF receptors leads to the recruitment of SH2 containing proteins which link the receptors to the activation of signaling pathways. Here we report that Grb10, an adapter protein of which the biological role remains unknown, is tyrosine phosphorylated in response to VEGF in endothelial cells (HUVEC) and in 293 cells expressing the VEGF receptor KDR. An intact SH2 domain is required for Grb10 tyrosine phosphorylation in response to VEGF, and this phosphorylation is mediated in part through the activation of Src. In HUVEC, VEGF increases Grb10 mRNA level. Expression of Grb10 in HUVEC or in KDR expressing 293 cells results in an increase in the amount and in the tyrosine phosphorylation of KDR. In 293 cells, this is correlated with the activation of signaling molecules, such as MAP kinase. By expressing mutants of Grb10, we found that the positive action of Grb10 is independent of its SH2 domain. Moreover, these Grb10 effects on KDR seem to be specific since Grb10 has no effect on the insulin receptor, and Grb2, another adapter protein, does not mimic the effect of Grb10 on KDR. In conclusion, we propose that VEGF up-regulates Grb10 level, which in turn increases KDR molecules, suggesting that Grb10 could be involved in a positive feedback loop in VEGF signaling.

  18. Vascular Remodeling in Experimental Hypertension

    Directory of Open Access Journals (Sweden)

    Norma R. Risler

    2005-01-01

    Full Text Available The basic hemodynamic abnormality in hypertension is an increased peripheral resistance that is due mainly to a decreased vascular lumen derived from structural changes in the small arteries wall, named (as a whole vascular remodeling. The vascular wall is an active, flexible, and integrated organ made up of cellular (endothelial cells, smooth muscle cells, adventitia cells, and fibroblasts and noncellular (extracellular matrix components, which in a dynamic way change shape or number, or reorganize in response to physiological and pathological stimuli, maintaining the integrity of the vessel wall in physiological conditions or participating in the vascular changes in cardiovascular diseases such as hypertension. Research focused on new signaling pathways and molecules that can participate in the mechanisms of vascular remodeling has provided evidence showing that vascular structure is not only affected by blood pressure, but also by mechanisms that are independent of the increased pressure. This review will provide an overview of the evidence, explaining some of the pathophysiologic mechanisms participating in the development of the vascular remodeling, in experimental models of hypertension, with special reference to the findings in spontaneously hypertensive rats as a model of essential hypertension, and in fructose-fed rats as a model of secondary hypertension, in the context of the metabolic syndrome. The understanding of the mechanisms producing the vascular alterations will allow the development of novel pharmacological tools for vascular protection in hypertensive disease.

  19. Patient-specific cardiovascular progenitor cells derived from integration-free induced pluripotent stem cells for vascular tissue regeneration.

    Science.gov (United States)

    Hu, Jiang; Wang, Yongyu; Jiao, Jiao; Liu, Zhongning; Zhao, Chao; Zhou, Zhou; Zhang, Zhanpeng; Forde, Kaitlynn; Wang, Lunchang; Wang, Jiangang; Baylink, David J; Zhang, Xiao-Bing; Gao, Shaorong; Yang, Bo; Chen, Y Eugene; Ma, Peter X

    2015-12-01

    Tissue-engineered blood vessels (TEBVs) are promising in regenerating a live vascular replacement. However, the vascular cell source is limited, and it is crucial to develop a scaffold that accommodates new type of vascular progenitor cells and facilitates in vivo lineage specification of the cells into functional vascular smooth muscle cells (VSMCs) to regenerate vascular tissue. In the present study, integration-free human induced pluripotent stem cells (hiPSCs) were established from patient peripheral blood mononuclear cells through episomal vector nucleofection of reprogramming factors. The established hiPSCs were then induced into mesoderm-originated cardiovascular progenitor cells (CVPCs) with a highly efficient directed lineage specification method. The derived CVPCs were demonstrated to be able to differentiate into functional VSMCs. Subcutaneous implantation of CVPCs seeded on macroporous nanofibrous poly(l-lactide) scaffolds led to in vivo VSMC lineage specification and matrix deposition inside the scaffolds. In summary, we established integration-free patient-specific hiPSCs from peripheral blood mononuclear cells, derived CVPCs through directed lineage specification, and developed an advanced scaffold for these progenitor cells to further differentiate in vivo into VSMCs and regenerate vascular tissue in a subcutaneous implantation model. This study has established an efficient patient-specific approach towards in vivo regeneration of vascular tissue. Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. Wnt inhibition promotes vascular specification of embryonic cardiac progenitors.

    Science.gov (United States)

    Reichman, David E; Park, Laura; Man, Limor; Redmond, David; Chao, Kenny; Harvey, Richard P; Taketo, Makoto M; Rosenwaks, Zev; James, Daylon

    2018-01-08

    Several studies have demonstrated a multiphasic role for Wnt signaling during embryonic cardiogenesis and developed protocols that enrich for cardiac derivatives during in vitro differentiation of human pluripotent stem cells (hPSCs). However, few studies have investigated the role of Wnt signaling in the specification of cardiac progenitor cells (CPCs) toward downstream fates. Using transgenic mice and hPSCs, we tracked endothelial cells (ECs) that originated from CPCs expressing NKX2.5. Analysis of EC-fated CPCs at discrete phenotypic milestones during hPSC differentiation identified reduced Wnt activity as a hallmark of EC specification, and the enforced activation or inhibition of Wnt reduced or increased, respectively, the degree of vascular commitment within the CPC population during both hPSC differentiation and mouse embryogenesis. Wnt5a, which has been shown to exert an inhibitory influence on Wnt signaling during cardiac development, was dynamically expressed during vascular commitment of hPSC-derived CPCs, and ectopic Wnt5a promoted vascular specification of hPSC-derived and mouse embryonic CPCs. © 2018. Published by The Company of Biologists Ltd.

  1. PC-3 prostate carcinoma cells release signal substances that influence the migratory activity of cells in the tumor's microenvironment

    Directory of Open Access Journals (Sweden)

    Zänker Kurt S

    2010-07-01

    Full Text Available Abstract Background Tumor cells interact with the cells of the microenvironment not only by cell-cell-contacts but also by the release of signal substances. These substances are known to induce tumor vascularization, especially under hypoxic conditions, but are also supposed to provoke other processes such as tumor innervation and inflammatory conditions. Inflammation is mediated by two organ systems, the neuroendocrine system and the immune system. Therefore, we investigated the influence of substances released by PC-3 human prostate carcinoma cells on SH-SY5Y neuroblastoma cells as well as neutrophil granulocytes and cytotoxic T lymphocytes, especially with regard to their migratory activity. Results PC-3 cells express several cytokines and growth factors including vascular endothelial growth factors, fibroblast growth factors, interleukins and neurotrophic factors. SH-SY5Y cells are impaired in their migratory activity by PC-3 cell culture supernatant, but orientate chemotactically towards the source. Neutrophil granulocytes increase their locomotory activity only in response to cell culture supernantant of hypoxic but not of normoxic PC-3 cells. In contrast, cytotoxic T lymphocytes do not change their migratory activity in response to either culture supernatant, but increase their cytotoxicity, whereas supernatant of normoxic PC-3 cells leads to a stronger increase than that of hypoxic PC-3 cells. Conclusions PC-3 cells release several signal substances that influence the behavior of the cells in the tumor's microenvironment, whereas no clear pattern towards proinflammatory or immunosuppressive conditions can be seen.

  2. Vascular function in health, hypertension, and diabetes

    DEFF Research Database (Denmark)

    Nyberg, Michael Permin; Gliemann, Lasse; Hellsten, Ylva

    2015-01-01

    muscle, which can affect muscle function. Central aspects in the vascular impairments are alterations in the formation of prostacyclin, the bioavailability of NO and an increased formation of vasoconstrictors and reactive oxygen species (ROS). Regular physical activity effectively improves vascular......, the increase in muscle blood flow required for oxygen supply during exercise is achieved through a substantial increase in vasodilators locally formed in the active muscle tissue that overcome the vasoconstrictor signals. Most of the vasodilator signals are mediated via endothelial cells, which lead...... to the formation of vasodilators such as nitric oxide (NO) and prostacyclin. In essential hypertension and type II diabetes, the endothelial function and regulation of vascular tone is impaired with consequent increases in peripheral vascular resistance and inadequate regulation of oxygen supply to the skeletal...

  3. Axon guidance molecules in vascular patterning.

    Science.gov (United States)

    Adams, Ralf H; Eichmann, Anne

    2010-05-01

    Endothelial cells (ECs) form extensive, highly branched and hierarchically organized tubular networks in vertebrates to ensure the proper distribution of molecular and cellular cargo in the vertebrate body. The growth of this vascular system during development, tissue repair or in disease conditions involves the sprouting, migration and proliferation of endothelial cells in a process termed angiogenesis. Surprisingly, specialized ECs, so-called tip cells, which lead and guide endothelial sprouts, share many feature with another guidance structure, the axonal growth cone. Tip cells are motile, invasive and extend numerous filopodial protrusions sensing growth factors, extracellular matrix and other attractive or repulsive cues in their tissue environment. Axonal growth cones and endothelial tip cells also respond to signals belonging to the same molecular families, such as Slits and Roundabouts, Netrins and UNC5 receptors, Semaphorins, Plexins and Neuropilins, and Eph receptors and ephrin ligands. Here we summarize fundamental principles of angiogenic growth, the selection and function of tip cells and the underlying regulation by guidance cues, the Notch pathway and vascular endothelial growth factor signaling.

  4. Cell sheet engineering using the stromal vascular fraction of adipose tissue as a vascularization strategy.

    Science.gov (United States)

    Costa, Marina; Cerqueira, Mariana T; Santos, Tírcia C; Sampaio-Marques, Belém; Ludovico, Paula; Marques, Alexandra P; Pirraco, Rogério P; Reis, Rui L

    2017-06-01

    Current vascularization strategies for Tissue Engineering constructs, in particular cell sheet-based, are limited by time-consuming and expensive endothelial cell isolation and/or by the complexity of using extrinsic growth factors. Herein, we propose an alternative strategy using angiogenic cell sheets (CS) obtained from the stromal vascular fraction (SVF) of adipose tissue that can be incorporated into more complex constructs. Cells from the SVF were cultured in normoxic and hypoxic conditions for up to 8days in the absence of extrinsic growth factors. Immunocytochemistry against CD31 and CD146 revealed spontaneous organization in capillary-like structures, more complex after hypoxic conditioning. Inhibition of HIF-1α pathway hindered capillary-like structure formation in SVF cells cultured in hypoxia, suggesting a role of HIF-1α. Moreover, hypoxic SVF cells showed a trend for increased secretion of angiogenic factors, which was reflected in increased network formation by endothelial cells cultured on matrigel using that conditioned medium. In vivo implantation of SVF CS in a mouse hind limb ischemia model revealed that hypoxia-conditioned CS led to improved restoration of blood flow. Both in vitro and in vivo data suggest that SVF CS can be used as simple and cost-efficient tools to promote functional vascularization of TE constructs. Neovascularization after implantation is a major obstacle for producing clinically viable cell sheet-based tissue engineered constructs. Strategies using endothelial cells and extrinsic angiogenic growth factors are expensive and time consuming and may raise concerns of tumorigenicity. In this manuscript, we describe a simplified approach using angiogenic cell sheets fabricated from the stromal vascular fraction of adipose tissue. The strong angiogenic behavior of these cell sheets, achieved without the use of external growth factors, was further stimulated by low oxygen culture. When implanted in an in vivo model of hind limb

  5. Vascular endothelial growth factor impairs the functional ability of dendritic cells through Id pathways

    International Nuclear Information System (INIS)

    Laxmanan, Sreenivas; Robertson, Stuart W.; Wang Enfeng; Lau, Julie S.; Briscoe, David M.; Mukhopadhyay, Debabrata

    2005-01-01

    Vascular endothelial growth factor (VEGF) is an angiogenic cytokine that plays an important role in tumor growth and progression. Recent evidence suggests an alternate, albeit indirect, role of VEGF on host immune response to tumors. VEGF appears to diminish host immunity by altering the function of major antigen-presenting cells such as dendritic cells (DCs) [D.I. Gabrilovich, T. Ishida, S. Nadaf, J.E. Ohm, D.P. Carbone, Antibodies to vascular endothelial growth factor enhance the efficacy of cancer immunotherapy by improving endogenous dendritic cell function, Clin. Cancer Res. 5 (1999) 2963-2970, D. Gabrilovich, T. Ishida, T. Oyama, S. Ran, V. Kravtsov, S. Nadaf, D.P. Carbone, Vascular endothelial growth factor inhibits the development of dendritic cells and dramatically affects the differentiation of multiple hematopoietic lineages in vivo, Blood 92 (1998) 4150-4166, T. Oyama, S. Ran, T. Ishida, S. Nadaf, L. Kerr, D.P. Carbone, D.I. Gabrilovich, Vascular endothelial growth factor affects dendritic cell maturation through the inhibition of nuclear factor-kappa B activation in hemopoietic progenitor cells, J. Immunol. 160 (1998) 1224-1232.]. DCs are prime initiators of host immunity as they are known to activate both primary as well as secondary immune responses [J. Banchereau, F. Briere, C. Caux, J. Davoust, S. Lebecque, Y.J. Liu, B. Pulendran, K. Palucka, Immunobiology of dendritic cells, Ann. Rev. Immunol. 18 (2000) 767-811.]. However, the exact nature of how VEGF suppresses DC function is not fully clear. In this report, we show that DCs cultured in the presence of VEGF are less potent in stimulating antigen-specific T-cells. Furthermore, by using DCs derived from Id1 -/- mice that are defective in Flt-1 signaling, we demonstrated that the inhibitory function of VEGF on DC function is most likely mediated by Flt-1. Thus, the role of VEGF in downregulating host immunity may highlight a unique role of VEGF in the pathogenesis of cancer

  6. Reciprocal interactions between endothelial cells and macrophages in angiogenic vascular niches

    Energy Technology Data Exchange (ETDEWEB)

    Baer, Caroline; Squadrito, Mario Leonardo [The Swiss Institute for Experimental Cancer Research (ISREC), School of Life Sciences, Swiss Federal Institute of Technology Lausanne (EPFL), 1015 Lausanne (Switzerland); Iruela-Arispe, M. Luisa, E-mail: arispe@mcdb.ucla.edu [The Swiss Institute for Experimental Cancer Research (ISREC), School of Life Sciences, Swiss Federal Institute of Technology Lausanne (EPFL), 1015 Lausanne (Switzerland); Department of Molecular, Cell and Developmental Biology and Molecular Biology Institute, University of California, Los Angeles 90095, CA (United States); De Palma, Michele, E-mail: michele.depalma@epfl.ch [The Swiss Institute for Experimental Cancer Research (ISREC), School of Life Sciences, Swiss Federal Institute of Technology Lausanne (EPFL), 1015 Lausanne (Switzerland)

    2013-07-01

    The ability of macrophages to promote vascular growth has been associated with the secretion and local delivery of classic proangiogenic factors (e.g., VEGF-A and proteases). More recently, a series of studies have also revealed that physical contact of macrophages with growing blood vessels coordinates vascular fusion of emerging sprouts. Interestingly, the interactions between macrophages and vascular endothelial cells (ECs) appear to be bidirectional, such that activated ECs also support the expansion and differentiation of proangiogenic macrophages from myeloid progenitors. Here, we discuss recent findings suggesting that dynamic angiogenic vascular niches might also exist in vivo, e.g. in tumors, where sprouting blood vessels and immature myeloid cells like monocytes engage in heterotypic interactions that are required for angiogenesis. Finally, we provide an account of emerging mechanisms of cell-to-cell communication that rely on secreted microvesicles, such as exosomes, which can offer a vehicle for the rapid exchange of molecules and genetic information between macrophages and ECs engaged in angiogenesis. -- Highlights: • Macrophages promote angiogenesis by secreting proangiogenic factors. • Macrophages modulate angiogenesis via cell-to-cell contacts with endothelial cells. • Endothelial cells promote the differentiation of proangiogenic macrophages. • Macrophages and endothelial cells may cooperate to form angiogenic vascular niches.

  7. Reciprocal interactions between endothelial cells and macrophages in angiogenic vascular niches

    International Nuclear Information System (INIS)

    Baer, Caroline; Squadrito, Mario Leonardo; Iruela-Arispe, M. Luisa; De Palma, Michele

    2013-01-01

    The ability of macrophages to promote vascular growth has been associated with the secretion and local delivery of classic proangiogenic factors (e.g., VEGF-A and proteases). More recently, a series of studies have also revealed that physical contact of macrophages with growing blood vessels coordinates vascular fusion of emerging sprouts. Interestingly, the interactions between macrophages and vascular endothelial cells (ECs) appear to be bidirectional, such that activated ECs also support the expansion and differentiation of proangiogenic macrophages from myeloid progenitors. Here, we discuss recent findings suggesting that dynamic angiogenic vascular niches might also exist in vivo, e.g. in tumors, where sprouting blood vessels and immature myeloid cells like monocytes engage in heterotypic interactions that are required for angiogenesis. Finally, we provide an account of emerging mechanisms of cell-to-cell communication that rely on secreted microvesicles, such as exosomes, which can offer a vehicle for the rapid exchange of molecules and genetic information between macrophages and ECs engaged in angiogenesis. -- Highlights: • Macrophages promote angiogenesis by secreting proangiogenic factors. • Macrophages modulate angiogenesis via cell-to-cell contacts with endothelial cells. • Endothelial cells promote the differentiation of proangiogenic macrophages. • Macrophages and endothelial cells may cooperate to form angiogenic vascular niches

  8. Prominent Vascularization Capacity of Mesenchymal Stem Cells in Collagen-Gold Nanocomposites.

    Science.gov (United States)

    Hsieh, Shu-Chen; Chen, Hui-Jye; Hsu, Shan-Hui; Yang, Yi-Chin; Tang, Cheng-Ming; Chu, Mei-Yun; Lin, Pei-Ying; Fu, Ru-Huei; Kung, Mei-Lang; Chen, Yun-Wen; Yeh, Bi-Wen; Hung, Huey-Shan

    2016-10-26

    The ideal characteristics of surface modification on the vascular graft for clinical application would be with excellent hemocompatibility, endothelialization capacity, and antirestenosis ability. Here, Fourier transform infrared spectroscopy (FTIR), surface enhanced Raman spectroscopy (SERS), atomic force microscopy (AFM), contact angle (θ) measurement, and thermogravimetric analysis (TGA) were used to evaluate the chemical and mechanical properties of collagen-gold nanocomposites (collagen+Au) with 17.4, 43.5, and 174 ppm of Au and suggested that the collagen+Au with 43.5 ppm of Au had better biomechanical properties and thermal stability than pure collagen. Besides, stromal-derived factor-1α (SDF-1α) at 50 ng/mL promoted the migration of mesenchymal stem cells (MSCs) on collagen+Au material through the α5β3 integrin/endothelial oxide synthase (eNOS)/metalloproteinase (MMP) signaling pathway which can be abolished by the knockdown of vascular endothelial growth factor (VEGF). The potentiality of collagen+Au with MSCs for vascular regeneration was evaluated by our in vivo rat model system. Artery tissues isolated from an implanted collagen+Au-coated catheter with MSCs expressed substantial CD-31 and α-SMA, displayed higher antifibrotic ability, antithrombotic activity, as well as anti-inflammatory response than all other materials. Our results indicated that the implantation of collagen+Au-coated catheters with MSCs could be a promising strategy for vascular regeneration.

  9. LPS Promotes Vascular Smooth Muscle Cells Proliferation Through the TLR4/Rac1/Akt Signalling Pathway

    Directory of Open Access Journals (Sweden)

    Qianran Yin

    2017-12-01

    Full Text Available Background/Aims: Lipopolysaccharide (LPS is a potent activator of vascular smooth muscle cells (VSMCs proliferation, but the underlying mechanism remains unknown. In this study, we knocked down Toll-like receptor 4 (TLR4 and Ras-related C3 botulinum toxin substrate 1 (Rac1 expression using small interfering RNA (siRNA in order to investigate the effects and possible mechanisms of LPS-induced VSMCs proliferation. Methods: VSMCs proliferation was monitored by 5-ethynyl-2’-deoxyuridine staining, and Rac1 activity was measured via Glutathione S-transferase pull-down assay. mRNAs encoding proliferating cell nuclear antigen (PCNA, smooth muscle 22α (SM22α, myosin heavy chain (MYH and transient receptor potential channel 1 (TRPC1 were detected by qRT-PCR. The expression of total Akt, p-Akt (308, p-Akt (473, SM22α, MYH and TRPC1 protein was analysed by Western blot. Results: Treatment with TLR4 siRNA (siTLR4 or Rac1 siRNA (siRac1 significantly decreased LPS-induced VSMCs proliferation. Moreover, LPS-induced activation of Rac1 through TLR4 was observed. Western blot analysis revealed that transfection with siTLR4 or siRac1 inhibited LPS-induced Akt phosphorylation. We discovered that LPS stimulated VSMCs proliferation via phenotypic modulation and that this effect was partially inhibited by pre-treatment with siTLR4 or siRac1. Further, TLR4 and Rac1 are involved in LPS-induced activation of TRPC1. Conclusion: This study suggests that LPS exerts an effect on VSMCs proliferation and that the TLR4/Rac1/Akt signalling pathway mediates this effect.

  10. Deleterious effects of tributyltin on porcine vascular stem cells physiology.

    Science.gov (United States)

    Bernardini, Chiara; Zannoni, Augusta; Bertocchi, Martina; Bianchi, Francesca; Salaroli, Roberta; Botelho, Giuliana; Bacci, Maria Laura; Ventrella, Vittoria; Forni, Monica

    2016-01-01

    The vascular functional and structural integrity is essential for the maintenance of the whole organism and it has been demonstrated that different types of vascular progenitor cells resident in the vessel wall play an important role in this process. The purpose of the present research was to observe the effect of tributyltin (TBT), a risk factor for vascular disorders, on porcine Aortic Vascular Precursor Cells (pAVPCs) in term of cytotoxicity, gene expression profile, functionality and differentiation potential. We have demonstrated that pAVPCs morphology deeply changed following TBT treatment. After 48h a cytotoxic effect has been detected and Annexin binding assay demonstrated that TBT induced apoptosis. The transcriptional profile of characteristic pericyte markers has been altered: TBT 10nM substantially induced alpha-SMA, while, TBT 500nM determined a significant reduction of all pericyte markers. IL-6 protein detected in the medium of pAVPCs treated with TBT at both doses studied and with a dose response. TBT has interfered with normal pAVPC functionality preventing their ability to support a capillary-like network. In addition TBT has determined an increase of pAVPC adipogenic differentiation. In conclusion in the present paper we have demonstrated that TBT alters the vascular stem cells in terms of structure, functionality and differentiating capability, therefore effects of TBT in blood should be deeply explored to understand the potential vascular risk associated with the alteration of vascular stem cell physiology. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. Osteoblastic and Vascular Endothelial Niches, Their Control on Normal Hematopoietic Stem Cells, and Their Consequences on the Development of Leukemia

    Directory of Open Access Journals (Sweden)

    Bella S. Guerrouahen

    2011-01-01

    Full Text Available Stem cell self-renewal is regulated by intrinsic mechanisms and extrinsic signals mediated via specialized microenvironments called “niches.” The best-characterized stem cell is the hematopoietic stem cell (HSC. Self-renewal and differentiation ability of HSC are regulated by two major elements: endosteal and vascular regulatory elements. The osteoblastic niche localized at the inner surface of the bone cavity might serve as a reservoir for long-term HSC storage in a quiescent state. Whereas the vascular niche, which consists of sinusoidal endothelial cell lining blood vessel, provides an environment for short-term HSC proliferation and differentiation. Both niches act together to maintain hematopoietic homeostasis. In this paper, we provide some principles applying to the hematopoietic niches, which will be useful in the study and understanding of other stem cell niches. We will discuss altered microenvironment signaling leading to myeloid lineage disease. And finally, we will review some data on the development of acute myeloid leukemia from a subpopulation called leukemia-initiating cells (LIC, and we will discuss on the emerging evidences supporting the influence of the microenvironment on chemotherapy resistance.

  12. Calcium signal communication in the central nervous system.

    Science.gov (United States)

    Braet, Katleen; Cabooter, Liesbet; Paemeleire, Koen; Leybaert, Luc

    2004-02-01

    The communication of calcium signals between cells is known to be operative between neurons where these signals integrate intimately with electrical and chemical signal communication at synapses. Recently, it has become clear that glial cells also exchange calcium signals between each other in cultures and in brain slices. This communication pathway has received utmost attention since it is known that astrocytic calcium signals can be induced by neuronal stimulation and can be communicated back to the neurons to modulate synaptic transmission. In addition to this, cells that are generally not considered as brain cells become progressively incorporated in the picture, as astrocytic calcium signals are reported to be communicated to endothelial cells of the vessel wall and can affect smooth muscle cell tone to influence the vessel diameter and thus blood flow. We review the available evidence for calcium signal communication in the central nervous system, taking into account a basic functional unit -the brain cell tripartite- consisting of neurons, glial cells and vascular cells and with emphasis on glial-vascular calcium signaling aspects.

  13. Circulating vascular cell adhesion molecule-1 in pre-eclampsia, gestational hypertension, and normal pregnancy: evidence of selective dysregulation of vascular cell adhesion molecule-1 homeostasis in pre-eclampsia.

    Science.gov (United States)

    Higgins, J R; Papayianni, A; Brady, H R; Darling, M R; Walshe, J J

    1998-08-01

    Our purpose was to investigate circulating levels of vascular cell adhesion molecule-1 in the peripheral and uteroplacental circulations during normotensive and hypertensive pregnancies. This prospective observational study involved 2 patient groups. Group 1 consisted of 22 women with pre-eclampsia and 30 normotensive women followed up longitudinally through pregnancy and post partum. There were an additional 13 women with established gestational hypertension. Group 2 consisted of 20 women with established pre-eclampsia and 19 normotensive control subjects undergoing cesarean delivery. Plasma levels of vascular cell adhesion molecule-1 were measured in blood drawn from the antecubital vein (group 1) and from both the antecubital and uterine veins (group 2). Data were analyzed by analysis of variance. In group 1 vascular cell adhesion molecule-1 levels did not change significantly throughout normal pregnancy and post partum. Women with established pre-eclampsia had increased vascular cell adhesion molecule-1 levels compared with the normotensive pregnancy group (P = .01). Vascular cell adhesion molecule-1 levels were not elevated in women with established gestational hypertension. In group 2 significantly higher levels of vascular cell adhesion molecule-1 were detected in the uteroplacental (P post partum, is not a feature of nonproteinuric gestational hypertension, and is not observed with other major leukocyte adhesion molecules. Induction of vascular cell adhesion molecule-1 expression in pre-eclampsia may contribute to leukocyte-mediated tissue injury in this condition or may reflect perturbation of other, previously unrecognized, functions of this molecule in pregnancy.

  14. Kaempferol inhibits vascular smooth muscle cell migration by modulating BMP-mediated miR-21 expression.

    Science.gov (United States)

    Kim, Kwangho; Kim, Sunghwan; Moh, Sang Hyun; Kang, Hara

    2015-09-01

    Bioflavonoids are known to induce cardioprotective effects by inhibiting vascular smooth muscle cell (VSMC) proliferation and migration. Kaempferol has been shown to inhibit VSMC proliferation. However, little is known about the effect of kaempferol on VSMC migration and the underlying molecular mechanisms. Our studies provide the first evidence that kaempferol inhibits VSMC migration by modulating the BMP4 signaling pathway and microRNA expression levels. Kaempferol activates the BMP signaling pathway, induces miR-21 expression and downregulates DOCK4, 5, and 7, leading to inhibition of cell migration. Moreover, kaempferol antagonizes the PDGF-mediated pro-migratory effect. Therefore, our study uncovers a novel regulatory mechanism of VSMC migration by kaempferol and suggests that miRNA modulation by kaempferol is a potential therapy for cardiovascular diseases.

  15. Interplay between coagulation and vascular inflammation in sickle cell disease

    Science.gov (United States)

    Sparkenbaugh, Erica; Pawlinski, Rafal

    2013-01-01

    Sickle cell disease is the most common inherited hematologic disorder that leads to the irreversible damage of multiple organs. Although sickling of red blood cells and vaso-occlusion are central to the pathophysiology of sickle cell disease the importance of hemolytic anemia and vasculopathy has been recently recognized. Hypercoagulation state is another prominent feature of sickle cell disease and is mediated by activation of both intrinsic and extrinsic coagulation pathways. Growing evidence demonstrates that coagulation may not only contribute to the thrombotic complications, but also to vascular inflammation associated with this disease. This article summarizes the role of vascular inflammation and coagulation activation, discusses potential mechanisms responsible for activation of coagulation and reviews recent data demonstrating the crosstalk between coagulation and vascular inflammation in sickle cell disease. PMID:23593937

  16. Cell lineage in vascularized bone transplantation.

    Science.gov (United States)

    Willems, Wouter F; Larsen, Mikko; Friedrich, Patricia F; Bishop, Allen T

    2014-01-01

    The biology behind vascularized bone allotransplantation remains largely unknown. We aim to study cell traffic between donor and recipient following bone auto-, and allografting. Vascularized femoral transplantation was performed with arteriovenous bundle implantation and short-term immunosuppression. Twenty male Piebald Virol Glaxo (PVG; RT1(c) ) rats received isotransplants from female PVG (RT1(c) ) rats and 22 male PVG rats received allografts from female Dark Agouti rats (DA, RT1(a) ), representing a major histocompatibility mismatch. Both groups were randomly analyzed at 4 or 18 weeks. Bone remodeling areas (inner and outer cortical samples) were labeled and laser capture microdissected. Analysis of sex-mismatch genes by real-time reverse transcription-polymerase chain reaction provided the relative Expression Ratio (rER) of donor (female) to recipient (male) cells. The rER was 0.456 ± 0.266 at 4 weeks and 0.749 ± 0.387 at 18 weeks (p = 0.09) in allotransplants. In isotransplants, the rER was 0.412 ± 0.239 and 0.467 ± 0.252 at 4 and 18 weeks, respectively (p = 0.21). At 4 weeks, the rER at the outer cortical area of isotransplants was significantly lower in isotransplants as compared with allotransplants (0.247 ± 0.181 vs. 0.549 ± 0.184, p = 0.007). Cells in the inner and outer cortical bone remodeling areas in isotransplants were mainly donor derived (rER 0.5) at 18 weeks. Applying novel methodology, we describe detailed cell traffic in vascularized bone transplants, elaborating our comprehension on bone transplantation. Copyright © 2013 Wiley Periodicals, Inc.

  17. Telmisartan activates endothelial nitric oxide synthase via Ser1177 phosphorylation in vascular endothelial cells.

    Directory of Open Access Journals (Sweden)

    Masahiro Myojo

    Full Text Available Because endothelial nitric oxide synthase (eNOS has anti-inflammatory and anti-arteriosclerotic functions, it has been recognized as one of the key molecules essential for the homeostatic control of blood vessels other than relaxation of vascular tone. Here, we examined whether telmisartan modulates eNOS function through its pleiotropic effect. Administration of telmisartan to mice significantly increased the phosphorylation level of eNOS (Ser1177 in the aortic endothelium, but administration of valsartan had no effect. Similarly, telmisartan treatment of human umbilical vein endothelial cells significantly increased the phosphorylation levels of AMP-activated protein kinase (Thr172 and eNOS and the concentration of intracellular guanosine 3',5'-cyclic monophosphate (cGMP. Furthermore, pretreatment with a p38 mitogen-activated protein kinase (p38 MAPK inhibitor suppressed the increased phosphorylation level of eNOS and intracellular cGMP concentration. These data show that telmisartan increases eNOS activity through Ser1177 phosphorylation in vascular endothelial cells mainly via p38 MAPK signaling.

  18. Baicalein attenuates vinorelbine-induced vascular endothelial cell injury and chemotherapeutic phlebitis in rabbits.

    Science.gov (United States)

    Ge, Gang-Feng; Shi, Wei-Wen; Yu, Chen-Huan; Jin, Xiao-Yin; Zhang, Huan-Huan; Zhang, Wen-You; Wang, Lu-Chen; Yu, Bing

    2017-03-01

    Chemotherapy is one of the major strategies for cancer treatment. Several antineoplastic drugs including vinorelbine (VRB) are commonly intravenously infused and liable to cause serious phlebitis. The therapeutic drugs for preventing this complication are limited. In this study, the mechanism of baicalein (BCN) was investigated on VRB-induced phlebitis in vivo and vascular endothelial cell injury in vitro. Treatment with BCN obviously attenuated vascular endothelial cell loss, edema, inflammatory cell infiltration and blood clots, and reduced the serum levels of TNF-α, IL-1β, IL-6 and ICAM-1 in the rabbit model of phlebitis induced by intravenous injection of VRB compared with vehicle. Further tests in vitro demonstrated that BCN lessened VRB-induced endothelial cell apoptosis, decreased intracellular ROS levels, suppressed phosphorylation of p38 and eventually inhibited activation of NF-κB signaling pathway. And these effects could be reversed by p38 agonist P79350. These results suggested that BCN exerted the protective effects against VRB-induced endothelial disruption in the rabbit model of phlebitis via inhibition of intracellular ROS generation and inactivation of p38/NF-κB pathway, leading to the decreased production of pro-inflammatory cytokines. Thus, BCN could be used as a potential agent for the treatment of phlebitis. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. Stem cell differentiation on electrospun nanofibrous substrates for vascular tissue engineering

    International Nuclear Information System (INIS)

    Jia, Lin; Prabhakaran, Molamma P.; Qin, Xiaohong; Ramakrishna, Seeram

    2013-01-01

    Nanotechnology has enabled the engineering of a variety of materials to meet the current challenges and requirements in vascular tissue regeneration. In our study, poly-L-lactide (PLLA) and hybrid PLLA/collagen (PLLA/Coll) nanofibers (3:1 and 1:1) with fiber diameters of 210 to 430 nm were fabricated by electrospinning. Their morphological, chemical and mechanical characterizations were carried out using scanning electron microscopy (SEM), attenuated total reflectance Fourier transform infrared (ATR-FTIR), and tensile instrument, respectively. Bone marrow derived mesenchymal stem cells (MSCs) seeded on electrospun nanofibers that are capable of differentiating into vascular cells have great potential for repair of the vascular system. We investigated the potential of MSCs for vascular cell differentiation in vitro on electrospun PLLA/Coll nanofibrous scaffolds using endothelial differentiation media. After 20 days of culture, MSC proliferation on PLLA/Coll(1:1) scaffolds was found 256% higher than the cell proliferation on PLLA scaffolds. SEM images showed that the MSC differentiated endothelial cells on PLLA/Coll scaffolds showed cobblestone morphology in comparison to the fibroblastic type of undifferentiated MSCs. The functionality of the cells in the presence of ‘endothelial induction media’, was further demonstrated from the immunocytochemical analysis, where the MSCs on PLLA/Coll (1:1) scaffolds differentiated to endothelial cells and expressed the endothelial cell specific proteins such as platelet endothelial cell adhesion molecule-1 (PECAM-1 or CD31) and Von Willebrand factor (vWF). From the results of the SEM analysis and protein expression studies, we concluded that the electrospun PLLA/Coll nanofibers could mimic the native vascular ECM environment and might be promising substrates for potential application towards vascular regeneration. - Highlights: • PLLA and PLLA/Coll nanofibers were electrospun. • Incorporation of collagen reduced fiber

  20. Stem cell differentiation on electrospun nanofibrous substrates for vascular tissue engineering

    Energy Technology Data Exchange (ETDEWEB)

    Jia, Lin [Key Laboratory of Textile Science and Technology, Ministry of Education, College of Textiles, Donghua University, No. 2999 North Renmin Road, Songjiang, Shanghai 201620 (China); Center for Nanofibers and Nanotechnology, E3-05-14, Nanoscience and Nanotechnology Initiative, Faculty of Engineering, National University of Singapore, 2 Engineering Drive 3, Singapore 117576 (Singapore); Prabhakaran, Molamma P., E-mail: nnimpp@nus.edu.sg [Center for Nanofibers and Nanotechnology, E3-05-14, Nanoscience and Nanotechnology Initiative, Faculty of Engineering, National University of Singapore, 2 Engineering Drive 3, Singapore 117576 (Singapore); Qin, Xiaohong, E-mail: xhqin@dhu.edu.cn [Key Laboratory of Textile Science and Technology, Ministry of Education, College of Textiles, Donghua University, No. 2999 North Renmin Road, Songjiang, Shanghai 201620 (China); Ramakrishna, Seeram [Center for Nanofibers and Nanotechnology, E3-05-14, Nanoscience and Nanotechnology Initiative, Faculty of Engineering, National University of Singapore, 2 Engineering Drive 3, Singapore 117576 (Singapore)

    2013-12-01

    Nanotechnology has enabled the engineering of a variety of materials to meet the current challenges and requirements in vascular tissue regeneration. In our study, poly-L-lactide (PLLA) and hybrid PLLA/collagen (PLLA/Coll) nanofibers (3:1 and 1:1) with fiber diameters of 210 to 430 nm were fabricated by electrospinning. Their morphological, chemical and mechanical characterizations were carried out using scanning electron microscopy (SEM), attenuated total reflectance Fourier transform infrared (ATR-FTIR), and tensile instrument, respectively. Bone marrow derived mesenchymal stem cells (MSCs) seeded on electrospun nanofibers that are capable of differentiating into vascular cells have great potential for repair of the vascular system. We investigated the potential of MSCs for vascular cell differentiation in vitro on electrospun PLLA/Coll nanofibrous scaffolds using endothelial differentiation media. After 20 days of culture, MSC proliferation on PLLA/Coll(1:1) scaffolds was found 256% higher than the cell proliferation on PLLA scaffolds. SEM images showed that the MSC differentiated endothelial cells on PLLA/Coll scaffolds showed cobblestone morphology in comparison to the fibroblastic type of undifferentiated MSCs. The functionality of the cells in the presence of ‘endothelial induction media’, was further demonstrated from the immunocytochemical analysis, where the MSCs on PLLA/Coll (1:1) scaffolds differentiated to endothelial cells and expressed the endothelial cell specific proteins such as platelet endothelial cell adhesion molecule-1 (PECAM-1 or CD31) and Von Willebrand factor (vWF). From the results of the SEM analysis and protein expression studies, we concluded that the electrospun PLLA/Coll nanofibers could mimic the native vascular ECM environment and might be promising substrates for potential application towards vascular regeneration. - Highlights: • PLLA and PLLA/Coll nanofibers were electrospun. • Incorporation of collagen reduced fiber

  1. Substance-specific importance of EGFR for vascular smooth muscle cells motility in primary culture.

    Science.gov (United States)

    Schreier, Barbara; Schwerdt, Gerald; Heise, Christian; Bethmann, Daniel; Rabe, Sindy; Mildenberger, Sigrid; Gekle, Michael

    2016-07-01

    Besides their importance for the vascular tone, vascular smooth muscle cells (VSMC) also contribute to pathophysiological vessel alterations. Various G-protein coupled receptor ligands involved in vascular dysfunction and remodeling can transactivate the epidermal growth factor receptor (EGFR) of VSMC, yet the importance of EGFR transactivation for the VSMC phenotype is incompletely understood. The aims of this study were (i) to characterize further the importance of the VSMC-EGFR for proliferation, migration and marker gene expression for inflammation, fibrosis and reactive oxygen species (ROS) homeostasis and (ii) to test the hypothesis that vasoactive substances (endothelin-1, phenylephrine, thrombin, vasopressin and ATP) rely differentially on the EGFR with respect to the abovementioned phenotypic alterations. In primary, aortic VSMC from mice without conditional deletion of the EGFR, proliferation, migration, marker gene expression (inflammation, fibrosis and ROS homeostasis) and cell signaling (ERK 1/2, intracellular calcium) were analyzed. VSMC-EGFR loss reduced collective cell migration and single cell migration probability, while no difference between the genotypes in single cell velocity, chemotaxis or marker gene expression could be observed under control conditions. EGF promoted proliferation, collective cell migration, chemokinesis and chemotaxis and leads to a proinflammatory gene expression profile in wildtype but not in knockout VSMC. Comparing the impact of five vasoactive substances (all reported to transactivate EGFR and all leading to an EGFR dependent increase in ERK1/2 phosphorylation), we demonstrate that the importance of EGFR for their action is substance-dependent and most apparent for crowd migration but plays a minor role for gene expression regulation. Copyright © 2016 Elsevier B.V. All rights reserved.

  2. Insulin resistance in vascular endothelial cells promotes intestinal tumour formation

    DEFF Research Database (Denmark)

    Wang, X; Häring, M-F; Rathjen, Thomas

    2017-01-01

    in vascular endothelial cells. Strikingly, these mice had 42% more intestinal tumours than controls, no change in tumour angiogenesis, but increased expression of vascular cell adhesion molecule-1 (VCAM-1) in primary culture of tumour endothelial cells. Insulin decreased VCAM-1 expression and leukocyte...... adhesion in quiescent tumour endothelial cells with intact insulin receptors and partly prevented increases in VCAM-1 and leukocyte adhesion after treatment with tumour necrosis factor-α. Knockout of insulin receptors in endothelial cells also increased leukocyte adhesion in mesenteric venules...

  3. Targeted modulation of reactive oxygen species in the vascular endothelium

    OpenAIRE

    Shuvaev, Vladimir V.; Muzykantov, Vladimir R.

    2011-01-01

    Endothelial cells lining vascular luminal surface represent an important site of signaling and injurious effects of reactive oxygen species (ROS) produced by other cells and endothelium itself in ischemia, inflammation and other pathological conditions. Targeted delivery of ROS modulating enzymes conjugated with antibodies to endothelial surface molecules (vascular immunotargeting) provides site-specific interventions in the endothelial ROS, unattainable by other formulations including PEG-mo...

  4. Using NASA's GeneLab for VESGEN Systems Analysis of Vascular Phenotypes from Stress and Other Signaling Pathways

    Science.gov (United States)

    Parsons-Wingerter, P.; Weitzel, Alexander; Vyas, R. J.; Murray, M. C.; Vickerman, M. B.; Bhattacharya, S.; Wyatt, S. E.

    2016-01-01

    One fundamental requirement shared by humans with all higher terrestrial life forms, including other vertebrates, insects, and higher land plants, is a complex, fractally branching vascular system. NASA's VESsel GENeration Analysis (VESGEN) software maps and quantifies vascular trees, networks, and tree-network composites according to weighted physiological rules such as vessel connectivity, tapering and bifurcational branching. According to fluid dynamics, successful vascular transport requires a complex distributed system of highly regulated laminar flow. Microvascular branching rules within vertebrates, dicot leaves and the other organisms therefore display many similarities. A unifying perspective is that vascular patterning offers a useful readout of molecular signaling that necessarily integrates these complex pathways. VESGEN has elucidated changes in vascular pattern resulting from inflammatory, developmental and other signaling within numerous tissues and major model organisms studied for Space Biology. For a new VESGEN systems approach, we analyzed differential gene expression in leaves of Arabidopsis thaliana reported by GeneLab (GLDS-7) for spaceflight. Vascularrelated changes in leaf gene expression were identified that can potentially be phenocopied by mutants in ground-based experiments. To link transcriptional, protein and other molecular change with phenotype, alterations in the spatial and dynamic dimensions of vascular patterns for Arabidopsis leaves and other model species are being co-localized with signaling patterns of single molecular expression analyzed as information dimensions. Previously, Drosophila microarray data returned from space suggested significant changes in genes related to wing venation development that include EGF, Notch, Hedghog, Wingless and Dpp signaling. Phenotypes of increasingly abnormal ectopic wing venation in the (non-spaceflight) Drosophila wing generated by overexpression of a Notch antagonist were analyzed by

  5. Fibro-vascular coupling in the control of cochlear blood flow.

    Directory of Open Access Journals (Sweden)

    Min Dai

    Full Text Available Transduction of sound in the cochlea is metabolically demanding. The lateral wall and hair cells are critically vulnerable to hypoxia, especially at high sound levels, and tight control over cochlear blood flow (CBF is a physiological necessity. Yet despite the importance of CBF for hearing, consensus on what mechanisms are involved has not been obtained.We report on a local control mechanism for regulating inner ear blood flow involving fibrocyte signaling. Fibrocytes in the super-strial region are spatially distributed near pre-capillaries of the spiral ligament of the albino guinea pig cochlear lateral wall, as demonstrably shown in transmission electron microscope and confocal images. Immunohistochemical techniques reveal the inter-connected fibrocytes to be positive for Na+/K+ ATPase β1 and S100. The connected fibrocytes display more Ca(2+ signaling than other cells in the cochlear lateral wall as indicated by fluorescence of a Ca(2+ sensor, fluo-4. Elevation of Ca(2+ in fibrocytes, induced by photolytic uncaging of the divalent ion chelator o-nitrophenyl EGTA, results in propagation of a Ca(2+ signal to neighboring vascular cells and vasodilation in capillaries. Of more physiological significance, fibrocyte to vascular cell coupled signaling was found to mediate the sound stimulated increase in cochlear blood flow (CBF. Cyclooxygenase-1 (COX-1 was required for capillary dilation.The findings provide the first evidence that signaling between fibrocytes and vascular cells modulates CBF and is a key mechanism for meeting the cellular metabolic demand of increased sound activity.

  6. A Dominant-Negative PPARγ Mutant Promotes Cell Cycle Progression and Cell Growth in Vascular Smooth Muscle Cells

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    Joey Z. Liu

    2009-01-01

    Full Text Available PPARγ ligands have been shown to have antiproliferative effects on many cell types. We herein report that a synthetic dominant-negative (DN PPARγ mutant functions like a growth factor to promote cell cycle progression and cell proliferation in human coronary artery smooth muscle cells (CASMCs. In quiescent CASMCs, adenovirus-expressed DN-PPARγ promoted G1→S cell cycle progression, enhanced BrdU incorporation, and increased cell proliferation. DN-PPARγ expression also markedly enhanced positive regulators of the cell cycle, increasing Rb and CDC2 phosphorylation and the expression of cyclin A, B1, D1, and MCM7. Conversely, overexpression of wild-type (WT or constitutively-active (CA PPARγ inhibited cell cycle progression and the activity and expression of positive regulators of the cell cycle. DN-PPARγ expression, however, did not up-regulate positive cell cycle regulators in PPARγ-deficient cells, strongly suggesting that DN-PPARγ effects on cell cycle result from blocking the function of endogenous wild-type PPARγ. DN-PPARγ expression enhanced phosphorylation of ERK MAPKs. Furthermore, the ERK specific-inhibitor PD98059 blocked DN-PPARγ-induced phosphorylation of Rb and expression of cyclin A and MCM7. Our data thus suggest that DN-PPARγ promotes cell cycle progression and cell growth in CASMCs by modulating fundamental cell cycle regulatory proteins and MAPK mitogenic signaling pathways in vascular smooth muscle cells (VSMCs.

  7. METACASPASE9 modulates autophagy to confine cell death to the target cells during Arabidopsis vascular xylem differentiation

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    Sacha Escamez

    2016-02-01

    Full Text Available We uncovered that the level of autophagy in plant cells undergoing programmed cell death determines the fate of the surrounding cells. Our approach consisted of using Arabidopsis thaliana cell cultures capable of differentiating into two different cell types: vascular tracheary elements (TEs that undergo programmed cell death (PCD and protoplast autolysis, and parenchymatic non-TEs that remain alive. The TE cell type displayed higher levels of autophagy when expression of the TE-specific METACASPASE9 (MC9 was reduced using RNAi (MC9-RNAi. Misregulation of autophagy in the MC9-RNAi TEs coincided with ectopic death of the non-TEs, implying the existence of an autophagy-dependent intercellular signalling from within the TEs towards the non-TEs. Viability of the non-TEs was restored when AUTOPHAGY2 (ATG2 was downregulated specifically in MC9-RNAi TEs, demonstrating the importance of autophagy in the spatial confinement of cell death. Our results suggest that other eukaryotic cells undergoing PCD might also need to tightly regulate their level of autophagy to avoid detrimental consequences for the surrounding cells.

  8. Nestin upregulation characterizes vascular remodeling secondary to hypertension in the rat.

    Science.gov (United States)

    Tardif, Kim; Hertig, Vanessa; Duquette, Natacha; Villeneuve, Louis; El-Hamamsy, Ismail; Tanguay, Jean-François; Calderone, Angelino

    2015-05-15

    Proliferation and hypertrophy of vascular smooth muscle cells represent hallmark features of vessel remodeling secondary to hypertension. The intermediate filament protein nestin was recently identified in vascular smooth muscle cells and in other cell types directly participated in proliferation. The present study tested the hypothesis that vessel remodeling secondary to hypertension was characterized by nestin upregulation in vascular smooth muscle cells. Two weeks after suprarenal abdominal aorta constriction of adult male Sprague-Dawley rats, elevated mean arterial pressure increased the media area and thickness of the carotid artery and aorta and concomitantly upregulated nestin protein levels. In the normal adult rat carotid artery, nestin immunoreactivity was observed in a subpopulation of vascular smooth muscle cells, and the density significantly increased following suprarenal abdominal aorta constriction. Filamentous nestin was detected in cultured rat carotid artery- and aorta-derived vascular smooth muscle cells and an analogous paradigm observed in human aorta-derived vascular smooth muscle cells. ANG II and EGF treatment of vascular smooth muscle cells stimulated DNA and protein synthesis and increased nestin protein levels. Lentiviral short-hairpin RNA-mediated nestin depletion of carotid artery-derived vascular smooth muscle cells inhibited peptide growth factor-stimulated DNA synthesis, whereas protein synthesis remained intact. These data have demonstrated that vessel remodeling secondary to hypertension was characterized in part by nestin upregulation in vascular smooth muscle cells. The selective role of nestin in peptide growth factor-stimulated DNA synthesis has revealed that the proliferative and hypertrophic responses of vascular smooth muscle cells were mediated by divergent signaling events. Copyright © 2015 the American Physiological Society.

  9. UAP56 is an important mediator of Angiotensin II/platelet derived growth factor induced vascular smooth muscle cell DNA synthesis and proliferation

    International Nuclear Information System (INIS)

    Sahni, Abha; Wang, Nadan; Alexis, Jeffrey

    2013-01-01

    Highlights: ► Knockdown of UAP56 inhibits Angiotensin II/PDGF induced vascular smooth muscle cell proliferation. ► UAP56 is a positive regulator of E2F transcriptional activation. ► UAP56 is present in the vessel wall of low flow carotid arteries. -- Abstract: Angiotensin (Ang) II and platelet-derived growth factor (PDGF) are important mediators of pathologic vascular smooth muscle cell (VSMC) proliferation. Identifying downstream mediators of Ang II and PDGF signaling may provide insights for therapies to improve vascular proliferative diseases. We have previously demonstrated that breakpoint cluster region (Bcr) is an important mediator of Ang II/PDGF signaling in VSMC. We have recently reported that the DExD/H box protein UAP56 is an interacting partner of Bcr in regulating VSMC DNA synthesis. We hypothesized that UAP56 itself is an important regulator of VSMC proliferation. In this report we demonstrate that knockdown of UAP56 inhibits Ang II/PDGF induced VSMC DNA synthesis and proliferation, and inhibits E2F transcriptional activity. In addition, we demonstrate that UAP56 is present in the vessel wall of low-flow carotid arteries. These findings suggest that UAP56 is a regulator of VSMC proliferation and identify UAP56 as a target for preventing vascular proliferative disease

  10. Enhanced endothelial cell functions on rosette nanotube-coated titanium vascular stents

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    Eli Fine

    2009-04-01

    Full Text Available Eli Fine1, Lijie Zhang1, Hicham Fenniri2, Thomas J Webster1 1Department of Engineering, Brown University, Providence, RI, USA; 2National Institute for Nanotechnology and Department of Chemistry, University of Alberta, Edmonton, AB, CanadaAbstract: One of the main problems with current vascular stents is a lack of endothelial cell interactions, which if sufficient, would create a uniform healthy endothelium masking the underlying foreign metal from inflammatory cell interference. Moreover, if endothelial cells from the arterial wall do not adhere to the stent, the stent can become loose and dislodge. Therefore, the objective of this in vitro study was to design a novel biomimetic nanostructured coating (that does not contain drugs on conventional vascular stent materials (specifically, titanium for improving vascular stent applications. Rosette nanotubes (RNTs are a new class of biomimetic nanotubes that self-assemble from DNA base analogs and have been shown in previous studies to sufficiently coat titanium and enhance osteoblast cell functions. RNTs have many desirable properties for use as vascular stent coatings including spontaneous self-assembly in body fluids, tailorable surface chemistry for specific implant applications, and nanoscale dimensions similar to those of the natural vascular extracellular matrix. Importantly, the results of this study provided the first evidence that RNTs functionalized with lysine (RNT–K, even at low concentrations, significantly increase endothelial cell density over uncoated titanium. Specifically, 0.01 mg/mL RNT–K coated titanium increased endothelial cell density by 37% and 52% compared to uncoated titanium after 4 h and three days, respectively. The excellent cytocompatibility properties of RNTs (as demonstrated here for the first time for endothelial cells suggest the need for the further exploration of these novel nanostructured materials for vascular stent applications.Keywords: stents

  11. Hypoxia-inducible factor-1 plays a role in phosphate-induced vascular smooth muscle cell calcification.

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    Mokas, Sophie; Larivière, Richard; Lamalice, Laurent; Gobeil, Stéphane; Cornfield, David N; Agharazii, Mohsen; Richard, Darren E

    2016-09-01

    Medial vascular calcification is a common complication of chronic kidney disease (CKD). Although elevated inorganic phosphate stimulates vascular smooth muscle cell (VSMC) osteogenic transdifferentiation and calcification, the mechanisms involved in their calcification during CKD are not fully defined. Because hypoxic gene activation is linked to CKD and stimulates bone cell osteogenic differentiation, we used in vivo and in vitro rodent models to define the role of hypoxic signaling during elevated inorganic phosphate-induced VSMC calcification. Cell mineralization studies showed that elevated inorganic phosphate rapidly induced VSMC calcification. Hypoxia strongly enhanced elevated inorganic phosphate-induced VSMC calcification and osteogenic transdifferentiation, as seen by osteogenic marker expression. Hypoxia-inducible factor-1 (HIF-1), the key hypoxic transcription factor, was essential for enhanced VSMC calcification. Targeting HIF-1 expression in murine VSMC blocked calcification in hypoxia with elevated inorganic phosphate while HIF-1 activators, including clinically used FG-4592/Roxadustat, recreated a procalcifying environment. Elevated inorganic phosphate rapidly activated HIF-1, even in normal oxygenation; an effect mediated by HIF-1α subunit stabilization. Thus, hypoxia synergizes with elevated inorganic phosphate to enhance VSMC osteogenic transdifferentiation. Our work identifies HIF-1 as an early CKD-related pathological event, prospective marker, and potential target against vascular calcification in CKD-relevant conditions. Copyright © 2016 International Society of Nephrology. Published by Elsevier Inc. All rights reserved.

  12. Vascular retraction driven by matrix softening

    Science.gov (United States)

    Valentine, Megan

    We recently discovered we can directly apply physical forces and monitor the downstream responses in a living organism in real time through manipulation of the blood vessels of a marine organism called, Botryllus schlosseri. The extracellular matrix (ECM) plays a key role in regulating vascular growth and homeostasis in Botryllus,a basal chordate which has a large, transparent extracorporeal vascular network that can encompass areas >100 cm2. We have determined that lysyl oxidase 1 (LOX1), which is responsible for cross-linking collagen, is expressed in all vascular cells and is critically important for vascular maintenance. Inhibition of LOX1 activity in vivo by the addition of a specific inhibitor, ß-aminopropionitrile (BAPN), caused a rapid, global regression of the entire vascular bed, with some vessels regressing >10 mm within 16 hrs. In this talk, I will discuss the molecular and cellular origins of this systemic remodeling event, which hinges upon the ability of the vascular cells to sense and respond to mechanical signals, while introducing this exciting new model system for studies of biological physics and mechanobiology. Collaborators: Anthony DeTomaso, Delany Rodriguez, Aimal Khankhel (UCSB).

  13. Plant GSK3 proteins regulate xylem cell differentiation downstream of TDIF-TDR signalling

    Science.gov (United States)

    Kondo, Yuki; Ito, Tasuku; Nakagami, Hirofumi; Hirakawa, Yuki; Saito, Masato; Tamaki, Takayuki; Shirasu, Ken; Fukuda, Hiroo

    2014-03-01

    During plant radial growth typically seen in trees, procambial and cambial cells act as meristematic cells in the vascular system to self-proliferate and differentiate into xylem cells. These two processes are regulated by a signalling pathway composed of a peptide ligand and its receptor; tracheary element differentiation inhibitory factor (TDIF) and TDIF RECEPTOR (TDR). Here we show that glycogen synthase kinase 3 proteins (GSK3s) are crucial downstream components of the TDIF signalling pathway suppressing xylem differentiation from procambial cells. TDR interacts with GSK3s at the plasma membrane and activates GSK3s in a TDIF-dependent fashion. Consistently, a specific inhibitor of plant GSK3s strongly induces xylem cell differentiation through BRI1-EMS SUPPRESSOR 1 (BES1), a well-known target transcription factor of GSK3s. Our findings provide insight into the regulation of cell fate determination in meristem maintenance.

  14. Inhibition of vascular endothelial growth factor signaling facilitates liver repair from acute ethanol-induced injury in zebrafish

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    Changwen Zhang

    2016-11-01

    Full Text Available Alcoholic liver disease (ALD results from alcohol overconsumption and is among the leading causes of liver-related morbidity and mortality worldwide. Elevated expression of vascular endothelial growth factor (VEGF and its receptors has been observed in ALD, but how it contributes to ALD pathophysiology is unclear. Here, we investigated the impact of VEGF signaling inhibition on an established zebrafish model of acute alcoholic liver injury. Kdrl activity was blocked by chemical inhibitor treatment or by genetic mutation. Exposing 4-day-old zebrafish larvae to 2% ethanol for 24 h induced hepatic steatosis, angiogenesis and fibrogenesis. The liver started self-repair once ethanol was removed. Although inhibiting Kdrl did not block the initial activation of hepatic stellate cells during ethanol treatment, it suppressed their proliferation, extracellular matrix protein deposition and fibrogenic gene expression after ethanol exposure, thus enhancing the liver repair. It also ameliorated hepatic steatosis and attenuated hepatic angiogenesis that accelerated after the ethanol treatment. qPCR showed that hepatic stellate cells are the first liver cell type to increase the expression of VEGF ligand and receptor genes in response to ethanol exposure. Both hepatic stellate cells and endothelial cells, but not hepatic parenchymal cells, expressed kdrl upon ethanol exposure and were likely the direct targets of Kdrl inhibition. Ethanol-induced steatosis and fibrogenesis still occurred in cloche mutants that have hepatic stellate cells but lack hepatic endothelial cells, and Kdrl inhibition suppressed both phenotypes in the mutants. These results suggest that VEGF signaling mediates interactions between activated hepatic stellate cells and hepatocytes that lead to steatosis. Our study demonstrates the involvement of VEGF signaling in regulating sustained liver injuries after acute alcohol exposure. It also provides a proof of principle of using the

  15. Differential Gene Expression of Primary Cultured Lymphatic and Blood Vascular Endothelial Cells

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    Gregory M. Nelson

    2007-12-01

    Full Text Available Blood vascular endothelial cells (BECs and the developmentally related lymphatic endothelial cells (LECs create complementary, yet distinct vascular networks. Each endothelial cell type interacts with flowing fluid and circulating cells, yet each vascular system has evolved specialized gene expression programs and thus both cell types display different phenotypes. BECs and LECs express distinct genes that are unique to their specific vascular microenvironment. Tumors also take advantage of the molecules that are expressed in these vascular systems to enhance their metastatic potential. We completed transcriptome analyses on primary cultured LECs and BECs, where each comparative set was isolated from the same individual. Differences were resolved in the expression of several major categories, such as cell adhesion molecules (CAMs, cytokines, cytokine receptors. We have identified new molecules that are associated with BECs (e.g., claudin-9, CXCL11, neurexin-1, neurexin-2, the neuronal growth factor regulator-1 and LECs (e.g., claudin-7, CD58, hyaluronan and proteoglycan link protein 1 (HAPLN1, the poliovirus receptor-related 3 molecule that may lead to novel therapeutic treatments for diseases of lymphatic or blood vessels, including metastasis of cancer to lymph nodes or distant organs.

  16. Towards the therapeutic use of vascular smooth muscle progenitor cells.

    Science.gov (United States)

    Merkulova-Rainon, Tatyana; Broquères-You, Dong; Kubis, Nathalie; Silvestre, Jean-Sébastien; Lévy, Bernard I

    2012-07-15

    Recent advances in the development of alternative proangiogenic and revascularization processes, including recombinant protein delivery, gene therapy, and cell therapy, hold the promise of greater efficacy in the management of cardiovascular disease in the coming years. In particular, vascular progenitor cell-based strategies have emerged as an efficient treatment approach to promote vessel formation and repair and to improve tissue perfusion. During the past decade, considerable progress has been achieved in understanding therapeutic properties of endothelial progenitor cells, while the therapeutic potential of vascular smooth muscle progenitor cells (SMPC) has only recently been explored; the number of the circulating SMPC being correlated with cardiovascular health. Several endogenous SMPC populations with varying phenotypes have been identified and characterized in the peripheral blood, bone marrow, and vascular wall. While the phenotypic entity of vascular SMPC is not fully defined and remains an evolving area of research, SMPC are increasingly recognized to play a special role in cardiovascular biology. In this review, we describe the current approaches used to define vascular SMPC. We further summarize the data on phenotype and functional properties of SMPC from various sources in adults. Finally, we discuss the role of SMPC in cardiovascular disease, including the contribution of SMPC to intimal proliferation, angiogenesis, and atherosclerotic plaque instability as well as the benefits resulting from the therapeutic use of SMPC.

  17. Role of the Vasa Vasorum and Vascular Resident Stem Cells in Atherosclerosis

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    Jun-ichi Kawabe

    2014-01-01

    Full Text Available Atherosclerosis is considered an “inside-out” response, that begins with the dysfunction of intimal endothelial cells and leads to neointimal plaque formation. The adventitia of large blood vessels has been recognized as an active part of the vessel wall that is involved in the process of atherosclerosis. There are characteristic changes in the adventitial vasa vasorum that are associated with the development of atheromatous plaques. However, whether vasa vasorum plays a causative or merely reactive role in the atherosclerotic process is not completely clear. Recent studies report that the vascular wall contains a number of stem/progenitor cells that may contribute to vascular remodeling. Microvessels serve as the vascular niche that maintains the resident stem/progenitor cells of the tissue. Therefore, the vasa vasorum may contribute to vascular remodeling through not only its conventional function as a blood conducting tube, but also its new conceptual function as a stem cell reservoir. This brief review highlights the recent advances contributing to our understanding of the role of the adventitial vasa vasorum in the atherosclerosis and discusses new concept that involves vascular-resident factors, the vasa vasorum and its associated vascular-resident stem cells, in the atherosclerotic process.

  18. From here to there, progenitor cells and stem cells are everywhere in lung vascular remodeling

    Directory of Open Access Journals (Sweden)

    Rebecca L. Heise

    2016-08-01

    Full Text Available The field of stem cell biology, cell therapy and regenerative medicine has expanded almost exponentially in the last decade. Clinical trials are evaluating the potential therapeutic use of stem cells in many adult and pediatric lung diseases with vascular component, such as bronchopulmonary dysplasia (BPD, chronic obstructive pulmonary disease (COPD, idiopathic pulmonary fibrosis (IPF or pulmonary arterial hypertension (PAH. Extensive research activity is exploring lung resident and circulating progenitor cells and their contribution to vascular complications of chronic lung diseases, and researchers hope to use resident or circulating stem/progenitor cells to treat chronic lung diseases and their vascular complications. It is becoming more and more clear that progress in mechanobiology will help to understand the various influences of physical forces and extracellular matrix composition on the phenotype and features of the progenitor cells and stem cells. The current review provides an overview of current concepts in the field.

  19. Redox Signaling and Its Impact on Skeletal and Vascular Responses to Spaceflight

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    Candice G. T. Tahimic

    2017-10-01

    Full Text Available Spaceflight entails exposure to numerous environmental challenges with the potential to contribute to both musculoskeletal and vascular dysfunction. The purpose of this review is to describe current understanding of microgravity and radiation impacts on the mammalian skeleton and associated vasculature at the level of the whole organism. Recent experiments from spaceflight and ground-based models have provided fresh insights into how these environmental stresses influence mechanisms that are related to redox signaling, oxidative stress, and tissue dysfunction. Emerging mechanistic knowledge on cellular defenses to radiation and other environmental stressors, including microgravity, are useful for both screening and developing interventions against spaceflight-induced deficits in bone and vascular function.

  20. Redox Signaling and Its Impact on Skeletal and Vascular Responses to Spaceflight

    Science.gov (United States)

    Tahimic, Candice; Globus, Ruth K.

    2018-01-01

    Spaceflight entails exposure to numerous environmental challenges with the potential to contribute to both musculoskeletal and vascular dysfunction. The purpose of this review is to describe current understanding of microgravity and radiation impacts on the mammalian skeleton and associated vasculature at the level of the whole organism. Recent experiments from spaceflight and groundbased models have provided fresh insights into how these environmental stresses influence mechanisms that are related to redox signaling, oxidative stress, and tissue dysfunction. Emerging mechanistic knowledge on cellular defenses to radiation and other environmental stressors, including microgravity, are useful for both screening and developing interventions against spaceflight-induced deficits in bone and vascular function.

  1. Composite vascular grafts with high cell infiltration by co-electrospinning

    International Nuclear Information System (INIS)

    Tan, Zhikai; Wang, Hongjie; Gao, Xiangkai; Liu, Tong; Tan, Yongjun

    2016-01-01

    There is an increasing demand for functional small-diameter vascular grafts (diameter < 6 mm) to be used in clinical arterial replacement. An ideal vascular graft should have appropriate biomechanical properties and be biocompatible. Electrospinning has become a popular polymer processing technique for vascular tissue engineering, but the grafts fabricated by electrospinning often have relatively small pores and low porosity, which limit cell infiltration into scaffolds and hinder the regeneration and remodeling of grafts. In the present study, we aimed to develop an efficient method to prepare electrospun composite vascular grafts comprising natural and synthetic materials. We fabricated grafts made of polycaprolactone, gelatin, and polyvinyl alcohol (PVA) by co-electrospinning, and the scaffolds were further functionalized by immobilizing heparin on them. The PVA fibers degraded rapidly in vivo and generated electrospun scaffolds with high porosity, which significantly enhanced cell proliferation and infiltration. The mechanical properties of the grafts are suitable for use in artery replacement. Heparin functionalization of the grafts yielded a good antithrombogenic effect, which was demonstrated in platelet adhesion tests. Moreover, in vitro and in vivo results demonstrated that the heparin release from the grafts enhanced the growth of endothelial cells, which is important for the endothelium of implanted grafts. The results of this study indicate that our method is effective and controllable for the fabrication of vascular grafts that meet the clinical requirements for blood vessel transplantation. - Highlights: • This study indicate an effective method for the fabrication of vascular grafts that meet the clinical requirements. • Co-electrospinning were used to fabricate grafts made of polycaprolactone (PCL), gelatin (GT), and polyvinyl alcohol (PVA). • PVA was used to create large pores within the hybrid scaffolds, thereby enhancing cell infiltration

  2. Composite vascular grafts with high cell infiltration by co-electrospinning

    Energy Technology Data Exchange (ETDEWEB)

    Tan, Zhikai, E-mail: tanzk@hnu.edu.cn; Wang, Hongjie; Gao, Xiangkai; Liu, Tong; Tan, Yongjun

    2016-10-01

    There is an increasing demand for functional small-diameter vascular grafts (diameter < 6 mm) to be used in clinical arterial replacement. An ideal vascular graft should have appropriate biomechanical properties and be biocompatible. Electrospinning has become a popular polymer processing technique for vascular tissue engineering, but the grafts fabricated by electrospinning often have relatively small pores and low porosity, which limit cell infiltration into scaffolds and hinder the regeneration and remodeling of grafts. In the present study, we aimed to develop an efficient method to prepare electrospun composite vascular grafts comprising natural and synthetic materials. We fabricated grafts made of polycaprolactone, gelatin, and polyvinyl alcohol (PVA) by co-electrospinning, and the scaffolds were further functionalized by immobilizing heparin on them. The PVA fibers degraded rapidly in vivo and generated electrospun scaffolds with high porosity, which significantly enhanced cell proliferation and infiltration. The mechanical properties of the grafts are suitable for use in artery replacement. Heparin functionalization of the grafts yielded a good antithrombogenic effect, which was demonstrated in platelet adhesion tests. Moreover, in vitro and in vivo results demonstrated that the heparin release from the grafts enhanced the growth of endothelial cells, which is important for the endothelium of implanted grafts. The results of this study indicate that our method is effective and controllable for the fabrication of vascular grafts that meet the clinical requirements for blood vessel transplantation. - Highlights: • This study indicate an effective method for the fabrication of vascular grafts that meet the clinical requirements. • Co-electrospinning were used to fabricate grafts made of polycaprolactone (PCL), gelatin (GT), and polyvinyl alcohol (PVA). • PVA was used to create large pores within the hybrid scaffolds, thereby enhancing cell infiltration

  3. Bone marrow stromal and vascular smooth muscle cells have chemosensory capacity via bitter taste receptor expression.

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    Troy C Lund

    Full Text Available The ability of cells to detect changes in the microenvironment is important in cell signaling and responsiveness to environmental fluctuations. Our interest is in understanding how human bone marrow stromal-derived cells (MSC and their relatives, vascular smooth muscle cells (VSMC, interact with their environment through novel receptors. We found, through a proteomics screen, that MSC express the bitter taste receptor, TAS2R46, a protein more typically localized to the taste bud. Expression was also confirmed in VSMCs. A prototypical bitter compound that binds to the bitter taste receptor class, denatonium, increased intracellular calcium release and decreased cAMP levels as well as increased the extracellular release of ATP in human MSC. Denatonium also bound and activated rodent VSMC with a change in morphology upon compound exposure. Finally, rodents given denatonium in vivo had a significant drop in blood pressure indicating a vasodilator response. This is the first description of chemosensory detection by MSC and VSMCs via a taste receptor. These data open a new avenue of research into discovering novel compounds that operate through taste receptors expressed by cells in the marrow and vascular microenvironments.

  4. Influence of smartphone Wi-Fi signals on adipose-derived stem cells.

    Science.gov (United States)

    Lee, Sang-Soon; Kim, Hyung-Rok; Kim, Min-Sook; Park, Sanghoon; Yoon, Eul-Sik; Park, Seung-Ha; Kim, Deok-Woo

    2014-09-01

    The use of smartphones is expanding rapidly around the world, thus raising the concern of possible harmful effects of radiofrequency generated by smartphones. We hypothesized that Wi-Fi signals from smartphones may have harmful influence on adipose-derived stem cells (ASCs). An in vitro study was performed to assess the influence of Wi-Fi signals from smartphones. The ASCs were incubated under a smartphone connected to a Wi-Fi network, which was uploading files at a speed of 4.8 Mbps for 10 hours a day, for a total of 5 days. We constructed 2 kinds of control cells, one grown in 37°C and the other grown in 39°C. After 5 days of Wi-Fi exposure from the smartphone, the cells underwent cell proliferation assay, apoptosis assay, and flow cytometry analysis. Three growth factors, vascular endothelial growth factor, hepatocyte growth factor, and transforming growth factor-β, were measured from ASC-conditioned media. Cell proliferation rate was higher in Wi-Fi-exposed cells and 39°C control cells compared with 37°C control cells. Apoptosis assay, flow cytometry analysis, and growth factor concentrations showed no remarkable differences among the 3 groups. We could not find any harmful effects of Wi-Fi electromagnetic signals from smartphones. The increased proliferation of ASCs under the smartphone, however, might be attributable to the thermal effect.

  5. Canonical hedgehog signaling augments tumor angiogenesis by induction of VEGF-A in stromal perivascular cells

    Science.gov (United States)

    Chen, Weiwei; Tang, Tracy; Eastham-Anderson, Jeff; Dunlap, Debra; Alicke, Bruno; Nannini, Michelle; Gould, Stephen; Yauch, Robert; Modrusan, Zora; DuPree, Kelly J.; Darbonne, Walter C.; Plowman, Greg; de Sauvage, Frederic J.; Callahan, Christopher A.

    2011-01-01

    Hedgehog (Hh) signaling is critical to the patterning and development of a variety of organ systems, and both ligand-dependent and ligand-independent Hh pathway activation are known to promote tumorigenesis. Recent studies have shown that in tumors promoted by Hh ligands, activation occurs within the stromal microenvironment. Testing whether ligand-driven Hh signaling promotes tumor angiogenesis, we found that Hh antagonism reduced the vascular density of Hh-producing LS180 and SW480 xenografts. In addition, ectopic expression of sonic hedgehog in low-Hh–expressing DLD-1 xenografts increased tumor vascular density, augmented angiogenesis, and was associated with canonical Hh signaling within perivascular tumor stromal cells. To better understand the molecular mechanisms underlying Hh-mediated tumor angiogenesis, we established an Hh-sensitive angiogenesis coculture assay and found that fibroblast cell lines derived from a variety of human tissues were Hh responsive and promoted angiogenesis in vitro through a secreted paracrine signal(s). Affymetrix array analyses of cultured fibroblasts identified VEGF-A, hepatocyte growth factor, and PDGF-C as candidate secreted proangiogenic factors induced by Hh stimulation. Expression studies of xenografts and angiogenesis assays using combinations of Hh and VEGF-A inhibitors showed that it is primarily Hh-induced VEGF-A that promotes angiogenesis in vitro and augments tumor-derived VEGF to promote angiogenesis in vivo. PMID:21597001

  6. Corynoxeine isolated from the hook of Uncaria rhynchophylla inhibits rat aortic vascular smooth muscle cell proliferation through the blocking of extracellular signal regulated kinase 1/2 phosphorylation.

    Science.gov (United States)

    Kim, Tack-Joong; Lee, Ju-Hyun; Lee, Jung-Jin; Yu, Ji-Yeon; Hwang, Bang-Yeon; Ye, Sang-Kyu; Shujuan, Li; Gao, Li; Pyo, Myoung-Yun; Yun, Yeo-Pyo

    2008-11-01

    The proliferation of vascular smooth muscle cells (VSMCs) induced by injury to the intima of arteries is an important etiologic factor in vascular proliferative disorders such as atherosclerosis and restenosis. Uncaria rhynchophylla is traditional Chinese herb that has been applied to the treatment of convulsive disorders, such as epilepsy, in China. In the present study, we examined whether corynoxeine exerts inhibitory effects on platelet-derived growth factor (PDGF)-BB-induced rat aortic VSMC proliferation and the possible mechanism of such effects. Pre-treatment of VSMCs with corynoxeine (5-50 microM) for 24 h resulted in significant decreases in cell number without any cytotoxicity; the inhibition percentages were 25.0+/-12.5, 63.0+/-27.5 and 88.0+/-12.5% at 5, 20 and 50 microM, respectively. Also, corynoxeine significantly inhibited the 50 ng/ml PDGF-BB-induced DNA synthesis of VSMCs in a concentration-dependent manner without any cytotoxicity; the inhibitions were 32.8+/-11.0, 51.8+/-8.0 and 76.9+/-7.4% at concentrations of 5, 20 and 50 microM, respectively. Pre-incubation of VSMCs with corynoxeine significantly inhibited PDGF-BB-induced extracellular signal-regulated kinase 1/2 (ERK1/2) activation, whereas corynoxeine had no effects on mitogen-activated protein kinase (MAPK/ERK)-activating kinase 1 and 2 (MEK1/2), Akt, or phospholipase C (PLC)gamma1 activation or on PDGF receptor beta (PDGF-Rbeta) phosphorylation. These results suggest that corynoxeine is a potent ERK1/2 inhibitor of key PDGF-BB-induced VSMC proliferation and may be useful in the prevention and treatment of vascular diseases and restenosis after angioplasty.

  7. Autocrine VEGF-VEGFR2-Neuropilin-1 signaling promotes glioma stem-like cell viability and tumor growth

    DEFF Research Database (Denmark)

    Hamerlik, Petra; Lathia, Justin D; Rasmussen, Rikke

    2012-01-01

    Although vascular endothelial growth factor (VEGF) receptor 2 (VEGFR2) is traditionally regarded as an endothelial cell protein, evidence suggests that VEGFRs may be expressed by cancer cells. Glioblastoma multiforme (GBM) is a lethal cancer characterized by florid vascularization and aberrantly...... elevated VEGF. Antiangiogenic therapy with the humanized VEGF antibody bevacizumab reduces GBM tumor growth; however, the clinical benefits are transient and invariably followed by tumor recurrence. In this study, we show that VEGFR2 is preferentially expressed on the cell surface of the CD133(+) human......, which is associated with VEGFR2-NRP1 recycling and a pool of active VEGFR2 within a cytosolic compartment of a subset of human GBM cells. Whereas bevacizumab failed to inhibit prosurvival effects of VEGFR2-mediated signaling, GSC viability under unperturbed or radiation-evoked stress conditions...

  8. Electron histochemical and autoradiographic studies of vascular smooth muscle cell

    International Nuclear Information System (INIS)

    Kameyama, Kohji; Aida, Takeo; Asano, Goro

    1982-01-01

    The authors have studied the vascular smooth muscle cell in the aorta and the arteries of brain, heart in autopsied cases, cholesterol fed rabbits and canine through electron histochemical and autoradiographic methods, using 3 H-proline and 3 H-thymidine. The vascular changes are variable presumably due to the functional and morphological difference of vessels. Aging, pathological condition and physiological requirement induce the disturbances of vascular functions as contractility. According to various pathological conditions, the smooth muscle cell altered their shape, surface properties and arrangement of subcellular organelles including changes in number. The morphological features of arteries during aging is characterized by the thickening of endothelium and media. Decreasing cellularity and increasing collagen contents in media. The autoradiographic and histochemical observations using periodic acid methenamine silver (PAM) and ruthenium red stains demonstrated that the smooth muscle cell is a connective tissue synthetic cell. The PAM impregnation have proved that the small bundle of microfilaments become associated with small conglomerate of collagen and elastic fibers. Cytochemical examination will provide sufficient evidence to establish the contribution of subcellular structure. The acid phosphatase play an important role in vascular disease and they are directly involved in cellular lipid metabolism in cholesterol fed animals, and the activity of Na-K ATPase on the plasma membrane may contribute to the regulation of vascular blood flow and vasospasms. Direct injury and subsequent abnormal contraction of smooth muscle cell may initiate increased permeability of plasma protein and lipid in the media layer and eventually may developed and enhance arteriosclerosis. (author)

  9. Epothilones Suppress Neointimal Thickening in the Rat Carotid Balloon-Injury Model by Inducing Vascular Smooth Muscle Cell Apoptosis through p53-Dependent Signaling Pathway.

    Science.gov (United States)

    Son, Dong Ju; Jung, Jae Chul; Hong, Jin Tae

    2016-01-01

    Microtubule stabilizing agents (MTSA) are known to inhibit vascular smooth muscle cell (VSMC) proliferation and migration, and effectively reduce neointimal hyperplasia and restenosis. Epothilones (EPOs), non-taxane MTSA, have been found to be effective in the inhibition of VSMC proliferation and neointimal formation by cell cycle arrest. However, effect of EPOs on apoptosis in hyper-proliferated VSMCs as a possible way to reduce neointimal formation and its action mechanism related to VSMC viability has not been suited yet. Thus, the purposes of the present study was to investigate whether EPOs are able to inhibit neointimal formation by inducing apoptosis within the region of neointimal hyperplasia in balloon-injured rat carotid artery, as well as underlying action mechanism. Treatment of EPO-B and EPO-D significantly induced apoptotic cell death and mitotic catastrophe in hyper-proliferated VSMCs, resulting in cell growth inhibition. Further, EPOs significantly suppressed VSMC proliferation and induced apoptosis by activation of p53-dependent apoptotic signaling pathway, Bax/cytochrome c/caspase-3. We further demonstrated that the local treatment of carotid arteries with EPOs potently inhibited neointimal lesion formation by induction of apoptosis in rat carotid injury model. Our findings demonstrate a potent anti-neointimal hyperplasia property of EPOs by inducing p53-depedent apoptosis in hyper-proliferated VSMCs.

  10. Human induced pluripotent stem cell-derived vascular smooth muscle cells

    DEFF Research Database (Denmark)

    Ayoubi, Sohrab; Sheikh, Søren P; Eskildsen, Tilde V

    2017-01-01

    . To this end, human induced pluripotent stem cells (hiPSCs) have generated great enthusiasm, and have been a driving force for development of novel strategies in drug discovery and regenerative cell-therapy for the last decade. Hence, investigating the mechanisms underlying the differentiation of hi......PSCs into specialized cell types such as cardiomyocytes, endothelial cells, and vascular smooth muscle cells (VSMCs) may lead to a better understanding of developmental cardiovascular processes and potentiate progress of safe autologous regenerative therapies in pathological conditions. In this review, we summarize...

  11. Promotion of Vascular Morphogenesis of Endothelial Cells Co-Cultured with Human Adipose-Derived Mesenchymal Stem Cells Using Polycaprolactone/Gelatin Nanofibrous Scaffolds

    Directory of Open Access Journals (Sweden)

    Yun-Min Kook

    2018-02-01

    Full Text Available New blood vessel formation is essential for tissue regeneration to deliver oxygen and nutrients and to maintain tissue metabolism. In the field of tissue engineering, in vitro fabrication of new artificial vessels has been a longstanding challenge. Here we developed a technique to reconstruct a microvascular system using a polycaprolactone (PCL/gelatin nanofibrous structure and a co-culture system. Using a simple electrospinning process, we fabricated three-dimensional mesh scaffolds to support the sprouting of human umbilical vein endothelial cells (HUVECs along the electrospun nanofiber. The co-culture with adipose-derived mesenchymal stem cells (ADSCs supported greater sprouting of endothelial cells (ECs. In a two-dimensional culture system, angiogenic cell assembly produced more effective direct intercellular interactions and paracrine signaling from ADSCs to assist in the vascular formation of ECs, compared to the influence of growth factor. Although vascular endothelial growth factor and sphingosine-1-phosphate were present during the culture period, the presence of ADSCs was the most important factor for the construction of a cell-assembled structure in the two-dimensional culture system. On the contrary, HUVECs co-cultured on PCL/gelatin nanofiber scaffolds produced mature and functional microvessel and luminal structures with a greater expression of vascular markers, including platelet endothelial cell adhesion molecule-1 and podocalyxin. Furthermore, both angiogenic factors and cellular interactions with ADSCs through direct contact and paracrine molecules contributed to the formation of enhanced engineered blood vessel structures. It is expected that the co-culture system of HUVECs and ADSCs on bioengineered PCL/gelatin nanofibrous scaffolds will promote robust and functional microvessel structures and will be valuable for the regeneration of tissue with restored blood vessels.

  12. Effect of microbubble ligation to cells on ultrasound signal enhancement: implications for targeted imaging.

    Science.gov (United States)

    Lankford, Miles; Behm, Carolyn Z; Yeh, James; Klibanov, Alexander L; Robinson, Peter; Lindner, Jonathan R

    2006-10-01

    Molecular imaging with contrast-enhanced ultrasound (CEU) relies on the detection of microbubbles retained in regions of disease. The aim of this study was to determine whether microbubble attachment to cells influences their acoustic signal generation and stability. Biotinylated microbubbles were attached to streptavidin-coated plates to derive density versus intensity relations during low- and high-power imaging. To assess damping from microbubble attachment to solid or cell surfaces, in vitro imaging was performed for microbubbles charge-coupled to methacrylate spheres and for vascular cell adhesion molecule-1-targeted microbubbles attached to endothelial cells. Signal enhancement on plates increased according to acoustic power and microbubble site density up to 300 mm. Microbubble signal was reduced by attachment to solid spheres during high- and low-power imaging but was minimally reduced by attachment to endothelial cells and only at low power. Attachment of targeted microbubbles to rigid surfaces results in damping and a reduction of their acoustic signal, which is not seen when microbubbles are attached to cells. A reliable concentration versus intensity relationship can be expected from microbubble attachment to 2-dimensional surfaces until a very high site density is reached.

  13. Cell Therapy Applications for Retinal Vascular Diseases: Diabetic Retinopathy and Retinal Vein Occlusion.

    Science.gov (United States)

    Park, Susanna S

    2016-04-01

    Retinal vascular conditions, such as diabetic retinopathy and retinal vein occlusion, remain leading causes of vision loss. No therapy exists to restore vision loss resulting from retinal ischemia and associated retinal degeneration. Tissue regeneration is possible with cell therapy. The goal would be to restore or replace the damaged retinal vasculature and the retinal neurons that are damaged and/or degenerating from the hypoxic insult. Currently, various adult cell therapies have been explored as potential treatment. They include mesenchymal stem cells, vascular precursor cells (i.e., CD34+ cells, hematopoietic cells or endothelial progenitor cells), and adipose stromal cells. Preclinical studies show that all these cells have a paracrine trophic effect on damaged ischemic tissue, leading to tissue preservation. Endothelial progenitor cells and adipose stromal cells integrate into the damaged retinal vascular wall in preclinical models of diabetic retinopathy and ischemia-reperfusion injury. Mesenchymal stem cells do not integrate as readily but appear to have a primary paracrine trophic effect. Early phase clinical trials have been initiated and ongoing using mesenchymal stem cells or autologous bone marrow CD34+ cells injected intravitreally as potential therapy for diabetic retinopathy or retinal vein occlusion. Adipose stromal cells or pluripotent stem cells differentiated into endothelial colony-forming cells have been explored in preclinical studies and show promise as possible therapies for retinal vascular disorders. The relative safety or efficacy of these various cell therapies for treating retinal vascular disorders have yet to be determined.

  14. Vascular Cell Induction Culture System Using Arabidopsis Leaves (VISUAL) Reveals the Sequential Differentiation of Sieve Element-Like Cells.

    Science.gov (United States)

    Kondo, Yuki; Nurani, Alif Meem; Saito, Chieko; Ichihashi, Yasunori; Saito, Masato; Yamazaki, Kyoko; Mitsuda, Nobutaka; Ohme-Takagi, Masaru; Fukuda, Hiroo

    2016-06-01

    Cell differentiation is a complex process involving multiple steps, from initial cell fate specification to final differentiation. Procambial/cambial cells, which act as vascular stem cells, differentiate into both xylem and phloem cells during vascular development. Recent studies have identified regulatory cascades for xylem differentiation. However, the molecular mechanism underlying phloem differentiation is largely unexplored due to technical challenges. Here, we established an ectopic induction system for phloem differentiation named Vascular Cell Induction Culture System Using Arabidopsis Leaves (VISUAL). Our results verified similarities between VISUAL-induced Arabidopsis thaliana phloem cells and in vivo sieve elements. We performed network analysis using transcriptome data with VISUAL to dissect the processes underlying phloem differentiation, eventually identifying a factor involved in the regulation of the master transcription factor gene APL Thus, our culture system opens up new avenues not only for genetic studies of phloem differentiation, but also for future investigations of multidirectional differentiation from vascular stem cells. © 2016 American Society of Plant Biologists. All rights reserved.

  15. Sphingosine signaling and atherogenesis

    DEFF Research Database (Denmark)

    Xu, Cang-bao; Hansen-Schwartz, Jacob; Edvinsson, Lars

    2004-01-01

    Sphingosine-1-phosphate (S1P) has diverse biological functions acting inside cells as a second messenger to regulate cell proliferation and survival, and extracellularly, as a ligand for a group of G protein-coupled receptors (GPCRs) named the endothelial differentiation gene (EDG) family. Five...... closely related GPCRs of EDG family (EDG1, EDG3, EDG5, EDG6, and EDG8) have recently been identified as high-affinity S1P receptors. These receptors are coupled via Gi, Gq, G12/13, and Rho. The signaling pathways are linked to vascular cell migration, proliferation, apoptosis, intracellular Ca2......+ mobilization, and expression of adhesion molecules. The formation of an atherosclerotic lesion occurs through activation of cellular events that include monocyte adhesion to the endothelium and vascular smooth muscle cell (VSMC) migration and proliferation. Thus, S1P signaling may play an important role...

  16. Inhibition of STAT3 phosphorylation by sulforaphane reduces adhesion molecule expression in vascular endothelial cell.

    Science.gov (United States)

    Cho, Young S; Kim, Chan H; Ha, Tae S; Ahn, Hee Y

    2015-11-18

    Intercellular adhesion molecule 1 (ICAM-1) and vascular cell adhesion molecule 1 (VCAM-1) play key roles in the initiation of vascular inflammation. In this study, we explored whether sulforaphane, a dietary phytochemical, can inhibit the expression of ICAM-1 and VCAM-1 in human umbilical vein endothelial cells (HUVEC) stimulated with lipopolysaccharide (LPS), and the mechanisms involved. Sulforaphane prevented the LPS-mediated increase in ICAM-1 and VCAM-1 expression, (P < 0.01) in HUVEC. Sulforaphane also prevented the LPS-mediated increase in the phosphorylation of signal transducer and activator of transcription 3 (STAT3) (P < 0.01). Stattic, a STAT3 inhibitor, reduced the LPS-induced expression of ICAM-1 and VCAM-1, and STAT3 phosphorylation (P < 0.01). STAT3 small interfering RNA treatment reduced the LPS-induced expression of ICAM-1, VCAM-1, and STAT3 (P < 0.01). Sulforaphane reduced LPS-mediated THP-1 monocyte adhesion to HUVEC (P < 0.01). In C57BL/6 mice, injection of LPS increased aortic ICAM-1 and VCAM-1 expression, and this effect was prevented by sulforaphane. These data provide insight into the mechanism through which sulforaphane partly reduces the expression of ICAM-1 and VCAM-1 on the vascular wall by inhibiting STAT3 phosphorylation.

  17. Ftr82 Is Critical for Vascular Patterning during Zebrafish Development

    Directory of Open Access Journals (Sweden)

    Hsueh-Wei Chang

    2017-01-01

    Full Text Available Cellular components and signaling pathways are required for the proper growth of blood vessels. Here, we report for the first time that a teleost-specific gene ftr82 (finTRIM family, member 82 plays a critical role in vasculature during zebrafish development. To date, there has been no description of tripartite motif proteins (TRIM in vascular development, and the role of ftr82 is unknown. In this study, we found that ftr82 mRNA is expressed during the development of vessels, and loss of ftr82 by morpholino (MO knockdown impairs the growth of intersegmental vessels (ISV and caudal vein plexus (CVP, suggesting that ftr82 plays a critical role in promoting ISV and CVP growth. We showed the specificity of ftr82 MO by analyzing ftr82 expression products and expressing ftr82 mRNA to rescue ftr82 morphants. We further showed that the knockdown of ftr82 reduced ISV cell numbers, suggesting that the growth impairment of vessels is likely due to a decrease of cell proliferation and migration, but not cell death. In addition, loss of ftr82 affects the expression of vascular markers, which is consistent with the defect of vascular growth. Finally, we showed that ftr82 likely interacts with vascular endothelial growth factor (VEGF and Notch signaling. Together, we identify teleost-specific ftr82 as a vascular gene that plays an important role for vascular development in zebrafish.

  18. Fluvastatin inhibits AGE-induced cell proliferation and migration via an ERK5-dependent Nrf2 pathway in vascular smooth muscle cells.

    Directory of Open Access Journals (Sweden)

    Ae-Rang Hwang

    Full Text Available Advanced glycation endproduct (AGE-induced vascular smooth muscle cell (VSMC proliferation and reactive oxygen species (ROS production are emerging as important mechanisms of diabetic vasculopathy, but little is known about the molecular mechanism responsible for the antioxidative effects of statins on AGEs. It has been reported that statins exert pleiotropic effects on the cardiovascular system due to decreases in AGE-induced cell proliferation, migration, and vascular inflammation. Thus, in the present study, the authors investigated the molecular mechanism by which statins decrease AGE-induced cell proliferation and VSMC migration. In cultured VSMCs, statins upregulated Nrf2-related antioxidant gene, NQO1 and HO-1, via an ERK5-dependent Nrf2 pathway. Inhibition of ERK5 by siRNA or BIX02189 (a specific ERK5 inhibitor reduced the statin-induced upregulations of Nrf2, NQO1, and HO-1. Furthermore, fluvastatin was found to significantly increase ARE promoter activity through ERK5 signaling, and to inhibit AGE-induced VSMC proliferation and migration as determined by MTT assay, cell counting, FACS analysis, a wound scratch assay, and a migration chamber assay. In addition, AGE-induced proliferation was diminished in the presence of Ad-CA-MEK5α encoding a constitutively active mutant form of MEK5α (an upstream kinase of ERK5, whereas depletion of Nrf2 restored statin-mediated reduction of AGE-induced cell proliferation. Moreover, fluvastatin suppressed the protein expressions of cyclin D1 and Cdk4, but induced p27, and blocked VSMC proliferation by regulating cell cycle. These results suggest statin-induced activation of an ERK5-dependent Nrf2 pathway reduces VSMC proliferation and migration induced by AGEs, and that the ERK5-Nrf2 signal module be viewed as a potential therapeutic target of vasculopathy in patients with diabetes and complications of the disease.

  19. A Hepatic GAbp-AMPK Axis Links Inflammatory Signaling to Systemic Vascular Damage

    Directory of Open Access Journals (Sweden)

    Katharina Niopek

    2017-08-01

    Full Text Available Increased pro-inflammatory signaling is a hallmark of metabolic dysfunction in obesity and diabetes. Although both inflammatory and energy substrate handling processes represent critical layers of metabolic control, their molecular integration sites remain largely unknown. Here, we identify the heterodimerization interface between the α and β subunits of transcription factor GA-binding protein (GAbp as a negative target of tumor necrosis factor alpha (TNF-α signaling. TNF-α prevented GAbpα and β complex formation via reactive oxygen species (ROS, leading to the non-energy-dependent transcriptional inactivation of AMP-activated kinase (AMPK β1, which was identified as a direct hepatic GAbp target. Impairment of AMPKβ1, in turn, elevated downstream cellular cholesterol biosynthesis, and hepatocyte-specific ablation of GAbpα induced systemic hypercholesterolemia and early macro-vascular lesion formation in mice. As GAbpα and AMPKβ1 levels were also found to correlate in obese human patients, the ROS-GAbp-AMPK pathway may represent a key component of a hepato-vascular axis in diabetic long-term complications.

  20. Endogenous Vascular Endothelial Growth Factor-A (VEGF-A) Maintains Endothelial Cell Homeostasis by Regulating VEGF Receptor-2 Transcription*

    Science.gov (United States)

    E, Guangqi; Cao, Ying; Bhattacharya, Santanu; Dutta, Shamit; Wang, Enfeng; Mukhopadhyay, Debabrata

    2012-01-01

    Vascular endothelial growth factor A (VEGF-A) is one of the most important factors controlling angiogenesis. Although the functions of exogenous VEGF-A have been widely studied, the roles of endogenous VEGF-A remain unclear. Here we focused on the mechanistic functions of endogenous VEGF-A in endothelial cells. We found that it is complexed with VEGF receptor 2 (VEGFR-2) and maintains a basal expression level for VEGFR-2 and its downstream signaling activation. Endogenous VEGF-A also controls expression of key endothelial specific genes including VEGFR-2, Tie-2, and vascular endothelial cadherin. Of importance, endogenous VEGF-A differs from exogenous VEGF-A by regulating VEGFR-2 transcription through mediation of FoxC2 binding to the FOX:ETS motif, and the complex formed by endogenous VEGF-A with VEGFR-2 is localized within the EEA1 (early endosome antigen 1) endosomal compartment. Taken together, our results emphasize the importance of endogenous VEGF-A in endothelial cells by regulating key vascular proteins and maintaining the endothelial homeostasis. PMID:22167188

  1. DMPD: Lipoprotein trafficking in vascular cells. Molecular Trojan horses and cellularsaboteurs. [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available 9287290 Lipoprotein trafficking in vascular cells. Molecular Trojan horses and cell...ml) Show Lipoprotein trafficking in vascular cells. Molecular Trojan horses and cellularsaboteurs. PubmedID ...9287290 Title Lipoprotein trafficking in vascular cells. Molecular Trojan horses

  2. A role for mitochondrial oxidants in stress-induced premature senescence of human vascular smooth muscle cells

    Directory of Open Access Journals (Sweden)

    Yogita Mistry

    2013-01-01

    Full Text Available Mitochondria are a major source of cellular oxidants and have been implicated in aging and associated pathologies, notably cardiovascular diseases. Vascular cell senescence is observed in experimental and human cardiovascular pathologies. Our previous data highlighted a role for angiotensin II in the induction of telomere-dependent and -independent premature senescence of human vascular smooth muscle cells and suggested this was due to production of superoxide by NADPH oxidase. However, since a role for mitochondrial oxidants was not ruled out we hypothesise that angiotensin II mediates senescence by mitochondrial superoxide generation and suggest that inhibition of superoxide may prevent vascular smooth muscle cell aging in vitro. Cellular senescence was induced using a stress-induced premature senescence protocol consisting of three successive once-daily exposure of cells to 1×10−8 mol/L angiotensin II and was dependent upon the type-1 angiotensin II receptor. Angiotensin stimulated NADPH-dependent superoxide production as estimated using lucigenin chemiluminescence in cell lysates and this was attenuated by the mitochondrial electron transport chain inhibitor, rotenone. Angiotensin also resulted in an increase in mitoSOX fluorescence indicating stimulation of mitochondrial superoxide. Significantly, the induction of senescence by angiotensin II was abrogated by rotenone and by the mitochondria-targeted superoxide dismutase mimetic, mitoTEMPO. These data suggest that mitochondrial superoxide is necessary for the induction of stress-induced premature senescence by angiotensin II and taken together with other data suggest that mitochondrial cross-talk with NADPH oxidases, via as yet unidentified signalling pathways, is likely to play a key role.

  3. Hydrogen sulfide potentiates interleukin-1β-induced nitric oxide production via enhancement of extracellular signal-regulated kinase activation in rat vascular smooth muscle cells

    International Nuclear Information System (INIS)

    Jeong, Sun-Oh; Pae, Hyun-Ock; Oh, Gi-Su; Jeong, Gil-Saeng; Lee, Bok-Soo; Lee, Seoul; Kim, Du Yong; Rhew, Hyun Yul; Lee, Kang-Min; Chung, Hun-Taeg

    2006-01-01

    Hydrogen sulfide (H 2 S) and nitric oxide (NO) are endogenously synthesized from L-cysteine and L-arginine, respectively. They might constitute a cooperative network to regulate their effects. In this study, we investigated whether H 2 S could affect NO production in rat vascular smooth muscle cells (VSMCs) stimulated with interleukin-1β (IL-1β). Although H 2 S by itself showed no effect on NO production, it augmented IL-β-induced NO production and this effect was associated with increased expression of inducible NO synthase (iNOS) and activation of nuclear factor (NF)-κB. IL-1β activated the extracellular signal-regulated kinase 1/2 (ERK1/2), and this activation was also enhanced by H 2 S. Inhibition of ERK1/2 activation by the selective inhibitor U0126 inhibited IL-1β-induced NF-κB activation, iNOS expression, and NO production either in the absence or presence of H 2 S. Our findings suggest that H 2 S enhances NO production and iNOS expression by potentiating IL-1β-induced NF-κB activation through a mechanism involving ERK1/2 signaling cascade in rat VSMCs

  4. Effects of infection with recombinant adenovirus on human vascular endothelial and smooth muscle cells

    NARCIS (Netherlands)

    Quax, P.H.A.; Lamfers, M.L.M.; Grimbergen, J.M.; Teeling, J.; Hoeben, R.C.; Nieuw Amerongen, G.P. van; Hinsbergh, V.W.M. van

    1996-01-01

    The plasminogen activation (PA) system is involved in vascular remodelling. Modulating its activity in vascular cells might be a way to interfere in processes such as angiogenesis and restenosis. Adenoviral vectors have become a favourable tool for direct gene transfer into vascular cells. In the

  5. Placental-Specific sFLT-1 e15a Protein Is Increased in Preeclampsia, Antagonizes Vascular Endothelial Growth Factor Signaling, and Has Antiangiogenic Activity.

    Science.gov (United States)

    Palmer, Kirsten R; Kaitu'u-Lino, Tu'uhevaha J; Hastie, Roxanne; Hannan, Natalie J; Ye, Louie; Binder, Natalie; Cannon, Ping; Tuohey, Laura; Johns, Terrance G; Shub, Alexis; Tong, Stephen

    2015-12-01

    In preeclampsia, the antiangiogenic factor soluble fms-like tyrosine kinase-1 (sFLT-1) is released from placenta into the maternal circulation, causing endothelial dysfunction and organ injury. A recently described splice variant, sFLT-1 e15a, is primate specific and the most abundant placentally derived sFLT-1. Therefore, it may be the major sFLT-1 isoform contributing to the pathophysiology of preeclampsia. sFLT-1 e15a protein remains poorly characterized: its bioactivity has not been comprehensively examined, and serum levels in normal and preeclamptic pregnancy have not been reported. We generated and validated an sFLT-1 e15a-specific ELISA to further characterize serum levels during pregnancy, and in the presence of preeclampsia. Furthermore, we performed assays to examine the bioactivity and antiangiogenic properties of sFLT-1 e15a protein. sFLT-1 e15a was expressed in the syncytiotrophoblast, and serum levels rose across pregnancy. Strikingly, serum levels were increased 10-fold in preterm preeclampsia compared with normotensive controls. We confirmed sFLT-1 e15a is bioactive and is able to inhibit vascular endothelial growth factor signaling of vascular endothelial growth factor receptor 2 and block downstream Akt phosphorylation. Furthermore, sFLT-1 e15a has antiangiogenic properties. sFLT-1 e15a decreased endothelial cell migration, invasion, and inhibited endothelial cell tube formation. Administering sFLT-1 e15a blocked vascular endothelial growth factor induced sprouts from mouse aortic rings ex vivo. We have demonstrated that sFLT-1 e15a is increased in preeclampsia, antagonizes vascular endothelial growth factor signaling, and has antiangiogenic activity. Future development of diagnostics and therapeutics for preeclampsia should consider targeting placentally derived sFLT-1 e15a. © 2015 American Heart Association, Inc.

  6. Advanced Glycation End-Products Induce Apoptosis of Vascular Smooth Muscle Cells: A Mechanism for Vascular Calcification

    Directory of Open Access Journals (Sweden)

    Sayo Koike

    2016-09-01

    Full Text Available Vascular calcification, especially medial artery calcification, is associated with cardiovascular death in patients with diabetes mellitus and chronic kidney disease (CKD. To determine the underlying mechanism of vascular calcification, we have demonstrated in our previous report that advanced glycation end-products (AGEs stimulated calcium deposition in vascular smooth muscle cells (VSMCs through excessive oxidative stress and phenotypic transition into osteoblastic cells. Since AGEs can induce apoptosis, in this study we investigated its role on VSMC apoptosis, focusing mainly on the underlying mechanisms. A rat VSMC line (A7r5 was cultured, and treated with glycolaldehyde-derived AGE-bovine serum albumin (AGE3-BSA. Apoptotic cells were identified by Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL staining. To quantify apoptosis, an enzyme-linked immunosorbent assay (ELISA for histone-complexed DNA fragments was employed. Real-time PCR was performed to determine the mRNA levels. Treatment of A7r5 cells with AGE3-BSA from 100 µg/mL concentration markedly increased apoptosis, which was suppressed by Nox inhibitors. AGE3-BSA significantly increased the mRNA expression of NAD(PH oxidase components including Nox4 and p22phox, and these findings were confirmed by protein levels using immunofluorescence. Dihydroethidisum assay showed that compared with cBSA, AGE3-BSA increased reactive oxygen species level in A7r5 cells. Furthermore, AGE3-induced apoptosis was significantly inhibited by siRNA-mediated knockdown of Nox4 or p22phox. Double knockdown of Nox4 and p22phox showed a similar inhibitory effect on apoptosis as single gene silencing. Thus, our results demonstrated that NAD(PH oxidase-derived oxidative stress are involved in AGEs-induced apoptosis of VSMCs. These findings might be important to understand the pathogenesis of vascular calcification in diabetes and CKD.

  7. The carboxyl terminal trimer of procollagen I induces pro-metastatic changes and vascularization in breast cancer cells xenografts

    International Nuclear Information System (INIS)

    Visigalli, Davide; Palmieri, Daniela; Strangio, Antonella; Astigiano, Simonetta; Barbieri, Ottavia; Casartelli, Gianluigi; Zicca, Antonio; Manduca, Paola

    2009-01-01

    The COOH terminal peptide of Pro-collagen type I (PICP, also called C3) is chemotactic for endothelial melanoma and breast cancer cells. PICP induces the expression of Metalloproteinases-2 and -9, of Vascular endothelial growth factor and of the chemokine CXCL-12 receptor CXCR4 in MDA MB231 breast carcinoma cells in vitro. We used a model of xenografts in BalbC/nude mice obtaining tumors by implanting in contro-lateral subcutaneous positions MDA MB231 cells added or not with purified PICP and studied the earlier phases of tumor development, up to 48 days from implant, by histology, immunostain and in situ hybridization. Addition of PICP promotes rapid vascularization of the tumors while does not affect mitotic and apoptotic indexes and overall tumor growth. PICP-treated, relative to control tumors, show up-modulation of Vascular endothelial factor, Metalloproteinase-9 and CXCR4, all tumor prognostic genes; they also show down-modulation of the endogenous Metalloproteinase inhibitor, reversion-inducing-cysteine-rich protein with kazal motifs, and a different pattern of modulation of Tissue Inhibitor of Metalloproteinase-2. These changes occur in absence of detectable expression of CXCL-12, up to 38 days, in control and treated tumors. PICP has an early promoting effect in the acquisition by the tumors of prometastatic phenotype. PICP may be play a relevant role in the productive interactions between stroma and tumor cells by predisposing the tumor cells to respond to the proliferation stimuli ensuing the activation of signaling by engagement of CXCR4 by cytokines and by fostering their extravasion, due to the induction of increased vascular development

  8. Do cell based tissue engineering products for meniscus regeneration influence vascularization?

    Science.gov (United States)

    Koch, Matthias; Ehrenreich, Tobias; Koehl, Gudrun; Pattappa, Girish; Pfeifer, Christian; Loibl, Markus; Müller, Michael; Nerlich, Michael; Angele, Peter; Zellner, Johannes

    2017-01-01

    Meniscus regeneration is observed within the peripheral, vascularized zone but decreases in the inner two thirds alongside the vascularization. Within this avascular area, cell-based tissue-engineering-approaches appear to be a promising strategy for the treatment of meniscal defects. Evaluation of the angiogenic potential of cell-based tissue-engineering-products for meniscus healing. Evaluation of angiogenesis induced by rabbit meniscus-pellets, meniscus-cells (MC) or mesenchymal stem-cells (MSC) in cell-based tissue-engineering-products within a rabbit meniscus-ring was performed using a transparent dorsal skin fold chamber in nude mice. Observations were undertaken during a 14 days period. Cell preconditioning differed between experimental groups. Immunohistochemical analysis of the regenerated tissue in the meniscus-ring induced by cell loaded composite scaffolds for differentiation and anti-angiogenic factors were performed. Meniscus-pellets and MSC-/MC-based tissue-engineering-products induced angiogenesis. An accelerated vascularization was detected in the group of meniscus-pellets derived from the vascularized zone compared to avascular meniscus-pellets. In terms of cell-based tissue-engineering-products, chondrogenic preconditioning resulted in significantly increased vessel growth. MSC-constructs showed an accelerated angiogenesis. Immunohistochemical evaluation showed a progressive differentiation and lower content for anti-angiogenic endostatin in the precultured group. Preconditioning of MC-/MSC-based tissue-engineering-products is a promising tool to influence the angiogenic potential of tissue-engineering-products and to adapt these properties according to the aimed tissue qualities.

  9. Dynamic and diverse changes in the functional properties of vascular smooth muscle cells in pulmonary hypertension.

    Science.gov (United States)

    Stenmark, Kurt R; Frid, Maria G; Graham, Brian B; Tuder, Rubin M

    2018-03-15

    Pulmonary hypertension (PH) is the end result of interaction between pulmonary vascular tone and a complex series of cellular and molecular events termed 'vascular remodelling'. The remodelling process, which can involve the entirety of pulmonary arterial vasculature, almost universally involves medial thickening, driven by increased numbers and hypertrophy of its principal cellular constituent, smooth muscle cells (SMCs). It is noted, however that SMCs comprise heterogeneous populations of cells, which can exhibit markedly different proliferative, inflammatory, and extracellular matrix production changes during remodelling. We further consider that these functional changes in SMCs of different phenotype and their role in PH are dynamic and may undergo significant changes over time (which we will refer to as cellular plasticity); no single property can account for the complexity of the contribution of SMC to pulmonary vascular remodelling. Thus, the approaches used to pharmacologically manipulate PH by targeting the SMC phenotype(s) must take into account processes that underlie dominant phenotypes that drive the disease. We present evidence for time- and location-specific changes in SMC proliferation in various animal models of PH; we highlight the transient nature (rather than continuous) of SMC proliferation, emphasizing that the heterogenic SMC populations that reside in different locations along the pulmonary vascular tree exhibit distinct responses to the stresses associated with the development of PH. We also consider that cells that have often been termed 'SMCs' may arise from many origins, including endothelial cells, fibroblasts and resident or circulating progenitors, and thus may contribute via distinct signalling pathways to the remodelling process. Ultimately, PH is characterized by long-lived, apoptosis-resistant SMC. In line with this key pathogenic characteristic, we address the acquisition of a pro-inflammatory phenotype by SMC that is essential

  10. Kaempferol Inhibits Angiogenesis by Suppressing HIF-1α and VEGFR2 Activation via ERK/p38 MAPK and PI3K/Akt/mTOR Signaling Pathways in Endothelial Cells.

    Science.gov (United States)

    Kim, Gi Dae

    2017-12-01

    Kaempferol has been shown to inhibit vascular formation in endothelial cells. However, the underlying mechanisms are not fully understood. In the present study, we evaluated whether kaempferol exerts antiangiogenic effects by targeting extracellular signal-regulated kinase (ERK)/p38 mitogen-activated protein kinase (MAPK) and phosphoinositide 3-kinase (PI3K)/Akt/mechanistic target of rapamycin (mTOR) signaling pathways in endothelial cells. Endothelial cells were treated with various concentrations of kaempferol for 24 h. Cell viability was determined by the 3- (4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide assay; vascular formation was analyzed by tube formation, wound healing, and mouse aortic ring assays. Activation of hypoxia-inducible factor-1α (HIF-1α), vascular endothelial growth factor receptor 2 (VEGFR2), ERK/p38 MAPK, and PI3K/Akt/mTOR was analyzed by Western blotting. Kaempferol significantly inhibited cell migration and tube formation in endothelial cells, and suppressed microvessel sprouting in the mouse aortic ring assay. Moreover, kaempferol suppressed the activation of HIF-1α, VEGFR2, and other markers of ERK/p38 MAPK and PI3K/Akt/mTOR signaling pathways in endothelial cells. These results suggest that kaempferol inhibits angiogenesis by suppressing HIF-1α and VEGFR2 activation via ERK/p38 MAPK and PI3K/Akt/mTOR signaling in endothelial cells.

  11. The Interaction Between IGF-1, Atherosclerosis and Vascular Aging

    Science.gov (United States)

    Higashi, Yusuke; Quevedo, Henry C.; Tiwari, Summit; Sukhanov, Sergiy; Shai, Shaw-Yung; Anwar, Asif; Delafontaine, Patrice

    2014-01-01

    The process of vascular aging encompasses alterations in the function of endothelial (EC) and vascular smooth muscle cells (VSMCs) via oxidation, inflammation, cell senescence and epigenetic modifications, increasing the probability of atherosclerosis. Aged vessels exhibit decreased endothelial antithrombogenic properties, increased reactive oxygen species (ROS) generation and inflammatory signaling, increased migration of VSMCs to the subintimal space, impaired angiogenesis and increased elastin degradation. The key initiating step in atherogenesis is subendothelial accumulation of apolipoprotein-B containing low density lipoproteins resulting in activation of endothelial cells and recruitment of monocytes. Activated endothelial cells secrete “chemokines” that interact with cognate chemokine receptors on monocytes and promote directional migration. Recruitment of immune cells establishes a pro-inflammatory status, further causing elevated oxidative stress, which in turn triggers a series of events including apoptotic or necrotic death of vascular and non-vascular cells. Increased oxidative stress is also considered to be a key factor in mechanisms of aging-associated changes in tissue integrity and function. Experimental evidence indicates that insulin-like growth factor-1 (IGF-1) exerts anti-oxidant, anti-inflammatory and pro-survival effects on the vasculature, reducing atherosclerotic plaque burden and promoting features of atherosclerotic plaque stability. PMID:24943302

  12. A pro-inflammatory role of deubiquitinating enzyme cylindromatosis (CYLD) in vascular smooth muscle cells

    International Nuclear Information System (INIS)

    Liu, Shuai; Lv, Jiaju; Han, Liping; Ichikawa, Tomonaga; Wang, Wenjuan; Li, Siying; Wang, Xing Li; Tang, Dongqi; Cui, Taixing

    2012-01-01

    Highlights: ► Cyld deficiency suppresses pro-inflammatory phenotypic switch of VSMCs. ► Cyld deficiency inhibits MAPK rather than NF-kB activity in inflamed VSMCs. ► CYLD is up-regulated in the coronary artery with neointimal hyperplasia. -- Abstract: CYLD, a deubiquitinating enzyme (DUB), is a critical regulator of diverse cellular processes, ranging from proliferation and differentiation to inflammatory responses, via regulating multiple key signaling cascades such as nuclear factor kappa B (NF-κB) pathway. CYLD has been shown to inhibit vascular lesion formation presumably through suppressing NF-κB activity in vascular cells. However, herein we report a novel role of CYLD in mediating pro-inflammatory responses in vascular smooth muscle cells (VSMCs) via a mechanism independent of NF-κB activity. Adenoviral knockdown of Cyld inhibited basal and the tumor necrosis factor alpha (TNFα)-induced mRNA expression of pro-inflammatory cytokines including monocyte chemotactic protein-1 (Mcp-1), intercellular adhesion molecule (Icam-1) and interleukin-6 (Il-6) in rat adult aortic SMCs (RASMCs). The CYLD deficiency led to increases in the basal NF-κB transcriptional activity in RASMCs; however, did not affect the TNFα-induced NF-κB activity. Intriguingly, the TNFα-induced IκB phosphorylation was enhanced in the CYLD deficient RASMCs. While knocking down of Cyld decreased slightly the basal expression levels of IκBα and IκBβ proteins, it did not alter the kinetics of TNFα-induced IκB protein degradation in RASMCs. These results indicate that CYLD suppresses the basal NF-κB activity and TNFα-induced IκB kinase activation without affecting TNFα-induced NF-κB activity in VSMCs. In addition, knocking down of Cyld suppressed TNFα-induced activation of mitogen activated protein kinases (MAPKs) including extracellular signal-activated kinases (ERK), c-Jun N-terminal kinase (JNK), and p38 in RASMCs. TNFα-induced RASMC migration and monocyte adhesion to

  13. Synergistic actions of hematopoietic and mesenchymal stem/progenitor cells in vascularizing bioengineered tissues.

    Directory of Open Access Journals (Sweden)

    Eduardo K Moioli

    Full Text Available Poor angiogenesis is a major road block for tissue repair. The regeneration of virtually all tissues is limited by angiogenesis, given the diffusion of nutrients, oxygen, and waste products is limited to a few hundred micrometers. We postulated that co-transplantation of hematopoietic and mesenchymal stem/progenitor cells improves angiogenesis of tissue repair and hence the outcome of regeneration. In this study, we tested this hypothesis by using bone as a model whose regeneration is impaired unless it is vascularized. Hematopoietic stem/progenitor cells (HSCs and mesenchymal stem/progenitor cells (MSCs were isolated from each of three healthy human bone marrow samples and reconstituted in a porous scaffold. MSCs were seeded in micropores of 3D calcium phosphate (CP scaffolds, followed by infusion of gel-suspended CD34(+ hematopoietic cells. Co-transplantation of CD34(+ HSCs and CD34(- MSCs in microporous CP scaffolds subcutaneously in the dorsum of immunocompromised mice yielded vascularized tissue. The average vascular number of co-transplanted CD34(+ and MSC scaffolds was substantially greater than MSC transplantation alone. Human osteocalcin was expressed in the micropores of CP scaffolds and was significantly increased upon co-transplantation of MSCs and CD34(+ cells. Human nuclear staining revealed the engraftment of transplanted human cells in vascular endothelium upon co-transplantation of MSCs and CD34(+ cells. Based on additional in vitro results of endothelial differentiation of CD34(+ cells by vascular endothelial growth factor (VEGF, we adsorbed VEGF with co-transplanted CD34(+ and MSCs in the microporous CP scaffolds in vivo, and discovered that vascular number and diameter further increased, likely owing to the promotion of endothelial differentiation of CD34(+ cells by VEGF. Together, co-transplantation of hematopoietic and mesenchymal stem/progenitor cells may improve the regeneration of vascular dependent tissues such as bone

  14. Oxytocin receptors expressed and coupled to Ca2+ signalling in a human vascular smooth muscle cell line.

    OpenAIRE

    Yazawa, H.; Hirasawa, A.; Horie, K.; Saita, Y.; Iida, E.; Honda, K.; Tsujimoto, G.

    1996-01-01

    1. In a human vascular smooth muscle cell line (HVSMC), binding experiments with [3H]-arginine8-vasopressin (AVP) have shown the existence of a homogeneous population of binding sites with affinity (Kd value) of 0.65 nM and a maximum number of binding sites (Bmax) of 122 fmol mg-1 protein. 2. Nonlabelled compounds compete for [3H]-AVP binding in the HVSMC membrane with an order of potency of oxytocin > lyspressin > or = AVP > Thr4, Gly7-oxytocin > (beta-mercapto-beta-beta-cyclopentamethylenep...

  15. NAMPT and NAMPT-controlled NAD Metabolism in Vascular Repair.

    Science.gov (United States)

    Wang, Pei; Li, Wen-Lin; Liu, Jian-Min; Miao, Chao-Yu

    2016-06-01

    Vascular repair plays important roles in postischemic remodeling and rehabilitation in cardiovascular and cerebrovascular disease, such as stroke and myocardial infarction. Nicotinamide adenine dinucleotide (NAD), a well-known coenzyme involved in electron transport chain for generation of adenosine triphosphate, has emerged as an important controller regulating various biological signaling pathways. Nicotinamide phosphoribosyltransferase (NAMPT) is the rate-limiting enzyme for NAD biosynthesis in mammals. NAMPT may also act in a nonenzymatic manner, presumably mediated by unknown receptor(s). Rapidly accumulating data in the past decade show that NAMPT and NAMPT-controlled NAD metabolism regulate fundamental biological functions in endothelial cells, vascular smooth muscle cells, and endothelial progenitor cells. The NAD-consuming proteins, including sirtuins, poly-ADP-ribose polymerases (PARPs), and CD38, may contribute to the regulatory effects of NAMPT-NAD axis in these cells and vascular repair. This review discusses the current data regarding NAMPT and NAMPT-controlled NAD metabolism in vascular repair and the clinical potential translational application of NAMPT-related products in treatment of cardiovascular and cerebrovascular disease.

  16. Macrophage migration inhibitory factor induces vascular leakage via autophagy

    Directory of Open Access Journals (Sweden)

    Hong-Ru Chen

    2015-01-01

    Full Text Available Vascular leakage is an important feature of acute inflammatory shock, which currently has no effective treatment. Macrophage migration inhibitory factor (MIF is a pro-inflammatory cytokine that can induce vascular leakage and plays an important role in the pathogenesis of shock. However, the mechanism of MIF-induced vascular leakage is still unclear. In this study, using recombinant MIF (rMIF, we demonstrated that MIF induced disorganization and degradation of junction proteins and increased the permeability of human endothelial cells in vitro. Western blotting analysis showed that rMIF treatment induced LC3 conversion and p62 degradation. Inhibition of autophagy with a PI3K inhibitor (3-MA, a ROS scavenger (NAC or autophagosomal-lysosomal fusion inhibitors (bafilomycin A1 and chloroquine rescued rMIF-induced vascular leakage, suggesting that autophagy mediates MIF-induced vascular leakage. The potential involvement of other signaling pathways was also studied using different inhibitors, and the results suggested that MIF-induced vascular leakage may occur through the ERK pathway. In conclusion, we showed that MIF triggered autophagic degradation of endothelial cells, resulting in vascular leakage. Inhibition of MIF-induced autophagy may provide therapeutic targets against vascular leakage in inflammatory shock.

  17. NLRC5 promotes cell proliferation via regulating the AKT/VEGF-A signaling pathway in hepatocellular carcinoma

    International Nuclear Information System (INIS)

    He, Ying-hua; Li, Ming-fang; Zhang, Xing-yan; Meng, Xiao-ming; Huang, Cheng; Li, Jun

    2016-01-01

    NLRC5, a newly found member of the NLR family and the largest member of nucleotide-binding, has been reported to regulate immune responses and is associated with hepatocellular carcinoma (HCC). We investigated the mechanisms and signaling pathways of NLRC5 in HCC progression. Increased expression of NLRC5, vascular endothelial growth factor-A (VEGF-A) were found in human HCC tissue. There was a positive correlation between NLRC5 and VEGF-A expression and cell proliferation were enhanced in NLRC5-overexpressing HepG2 cells, but inhibited in cells with NLRC5 silencing treatment. Interestingly, we found that up-regulation of NLRC5 also coordinated the activation of PI3K/AKT signaling pathway. An AKT inhibitor LY294002 blocked VEGF-A expression and AKT phosphorylation in HepG2 cells and NLRC5-overexpressing HepG2 cells. These results demonstrate that NLRC5 promotes HCC progression via the AKT/VEGF-A signaling pathway.

  18. Bone Marrow Vascular Niche: Home for Hematopoietic Stem Cells

    Directory of Open Access Journals (Sweden)

    Ningning He

    2014-01-01

    Full Text Available Though discovered later than osteoblastic niche, vascular niche has been regarded as an alternative indispensable niche operating regulation on hematopoietic stem cells (HSCs. As significant progresses gained on this type niche, it is gradually clear that the main work of vascular niche is undertaking to support hematopoiesis. However, compared to what have been defined in the mechanisms through which the osteoblastic niche regulates hematopoiesis, we know less in vascular niche. In this review, based on research data hitherto we will focus on component foundation and various functions of vascular niche that guarantee the normal hematopoiesis process within bone marrow microenvironments. And the possible pathways raised by various research results through which this environment undergoes its function will be discussed as well.

  19. Magnesium Inhibits Wnt/β-Catenin Activity and Reverses the Osteogenic Transformation of Vascular Smooth Muscle Cells

    Science.gov (United States)

    Montes de Oca, Addy; Guerrero, Fatima; Martinez-Moreno, Julio M.; Madueño, Juan A.; Herencia, Carmen; Peralta, Alan; Almaden, Yolanda; Lopez, Ignacio; Aguilera-Tejero, Escolastico; Gundlach, Kristina; Büchel, Janine; Peter, Mirjam E.; Passlick-Deetjen, Jutta; Rodriguez, Mariano; Muñoz-Castañeda, Juan R.

    2014-01-01

    Magnesium reduces vascular smooth muscle cell (VSMC) calcification in vitro but the mechanism has not been revealed so far. This work used only slightly increased magnesium levels and aimed at determining: a) whether inhibition of magnesium transport into the cell influences VSMC calcification, b) whether Wnt/β-catenin signaling, a key mediator of osteogenic differentiation, is modified by magnesium and c) whether magnesium can influence already established vascular calcification. Human VSMC incubated with high phosphate (3.3 mM) and moderately elevated magnesium (1.4 mM) significantly reduced VSMC calcification and expression of the osteogenic transcription factors Cbfa-1 and osterix, and up-regulated expression of the natural calcification inhibitors matrix Gla protein (MGP) and osteoprotegerin (OPG). The protective effects of magnesium on calcification and expression of osteogenic markers were no longer observed in VSMC cultured with an inhibitor of cellular magnesium transport (2-aminoethoxy-diphenylborate [2-APB]). High phosphate induced activation of Wnt/β-catenin pathway as demonstrated by the translocation of β-catenin into the nucleus, increased expression of the frizzled-3 gene, and downregulation of Dkk-1 gene, a specific antagonist of the Wnt/β-catenin signaling pathway. The addition of magnesium however inhibited phosphate-induced activation of Wnt/β-catenin signaling pathway. Furthermore, TRPM7 silencing using siRNA resulted in activation of Wnt/β-catenin signaling pathway. Additional experiments were performed to test the ability of magnesium to halt the progression of already established VSMC calcification in vitro. The delayed addition of magnesium decreased calcium content, down-regulated Cbfa-1 and osterix and up-regulated MGP and OPG, when compared with a control group. This effect was not observed when 2-APB was added. In conclusion, magnesium transport through the cell membrane is important to inhibit VSMC calcification in vitro

  20. Transforming growth factor β-activated kinase 1 negatively regulates interleukin-1α-induced stromal-derived factor-1 expression in vascular smooth muscle cells

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Bin [Department of Hepatobiliary Surgery, Union Hospital, Tongji Medical College, Huangzhong University of Science and Technology, Wuhan 430022 (China); Li, Wei [Department of Gerontology, Union Hospital, Tongji Medical College, Huangzhong University of Science and Technology, Wuhan 430022 (China); Zheng, Qichang [Department of Hepatobiliary Surgery, Union Hospital, Tongji Medical College, Huangzhong University of Science and Technology, Wuhan 430022 (China); Qin, Tao [Department of Hepatobiliary Pancreatic Surgery, People' s Hospital of Zhengzhou University, School of Medicine, Zhengzhou University, Zhengzhou 450003 (China); Wang, Kun; Li, Jinjin; Guo, Bing; Yu, Qihong; Wu, Yuzhe; Gao, Yang; Cheng, Xiang; Hu, Shaobo; Kumar, Stanley Naveen [Department of Hepatobiliary Surgery, Union Hospital, Tongji Medical College, Huangzhong University of Science and Technology, Wuhan 430022 (China); Liu, Sanguang, E-mail: sanguang1998@sina.com [Department of Hepatobiliary Surgery, The Second Hospital, Hebei Medical University, Shijiazhuang 050000 (China); Song, Zifang, E-mail: zsong@hust.edu.cn [Department of Hepatobiliary Surgery, Union Hospital, Tongji Medical College, Huangzhong University of Science and Technology, Wuhan 430022 (China)

    2015-07-17

    Stromal-derived Factor-1 (SDF-1) derived from vascular smooth muscle cells (VSMCs) contributes to vascular repair and remodeling in various vascular diseases. In this study, the mechanism underlying regulation of SDF-1 expression by interleukin-1α (IL-1α) was investigated in primary rat VSMCs. We found IL-1α promotes SDF-1 expression by up-regulating CCAAT-enhancer-binding protein β (C/EBPβ) in an IκB kinase β (IKKβ) signaling-dependent manner. Moreover, IL-1α-induced expression of C/EBPβ and SDF-1 was significantly potentiated by knockdown of transforming growth factor β-activated kinase 1 (TAK1), an upstream activator of IKKβ signaling. In addition, we also demonstrated that TAK1/p38 mitogen-activated protein kinase (p38 MAPK) signaling exerted negative effect on IL-1α-induced expression of C/EBPβ and SDF-1 through counteracting ROS-dependent up-regulation of nuclear factor erythroid 2-related factor 2 (NRF2). In conclusion, TAK1 acts as an important regulator of IL-1α-induced SDF-1 expression in VSMCs, and modulating activity of TAK1 may serve as a potential strategy for modulating vascular repair and remodeling. - Highlights: • IL-1α induces IKKβ signaling-dependent SDF-1 expression by up-regulating C/EBPβ. • Activation of TAK1 by IL-1α negatively regulates C/EBPβ-dependent SDF-1 expression. • IL-1α-induced TAK1/p38 MAPK signaling counteracts ROS-dependent SDF-1 expression. • TAK1 counteracts IL-1α-induced SDF-1 expression by attenuating NRF2 up-regulation.

  1. Transforming growth factor β-activated kinase 1 negatively regulates interleukin-1α-induced stromal-derived factor-1 expression in vascular smooth muscle cells

    International Nuclear Information System (INIS)

    Yang, Bin; Li, Wei; Zheng, Qichang; Qin, Tao; Wang, Kun; Li, Jinjin; Guo, Bing; Yu, Qihong; Wu, Yuzhe; Gao, Yang; Cheng, Xiang; Hu, Shaobo; Kumar, Stanley Naveen; Liu, Sanguang; Song, Zifang

    2015-01-01

    Stromal-derived Factor-1 (SDF-1) derived from vascular smooth muscle cells (VSMCs) contributes to vascular repair and remodeling in various vascular diseases. In this study, the mechanism underlying regulation of SDF-1 expression by interleukin-1α (IL-1α) was investigated in primary rat VSMCs. We found IL-1α promotes SDF-1 expression by up-regulating CCAAT-enhancer-binding protein β (C/EBPβ) in an IκB kinase β (IKKβ) signaling-dependent manner. Moreover, IL-1α-induced expression of C/EBPβ and SDF-1 was significantly potentiated by knockdown of transforming growth factor β-activated kinase 1 (TAK1), an upstream activator of IKKβ signaling. In addition, we also demonstrated that TAK1/p38 mitogen-activated protein kinase (p38 MAPK) signaling exerted negative effect on IL-1α-induced expression of C/EBPβ and SDF-1 through counteracting ROS-dependent up-regulation of nuclear factor erythroid 2-related factor 2 (NRF2). In conclusion, TAK1 acts as an important regulator of IL-1α-induced SDF-1 expression in VSMCs, and modulating activity of TAK1 may serve as a potential strategy for modulating vascular repair and remodeling. - Highlights: • IL-1α induces IKKβ signaling-dependent SDF-1 expression by up-regulating C/EBPβ. • Activation of TAK1 by IL-1α negatively regulates C/EBPβ-dependent SDF-1 expression. • IL-1α-induced TAK1/p38 MAPK signaling counteracts ROS-dependent SDF-1 expression. • TAK1 counteracts IL-1α-induced SDF-1 expression by attenuating NRF2 up-regulation

  2. In-depth evaluation of commercially available human vascular smooth muscle cells phenotype: Implications for vascular tissue engineering

    Energy Technology Data Exchange (ETDEWEB)

    Timraz, Sara B.H., E-mail: sara.timraz@kustar.ac.ae [Department of Biomedical Engineering, Khalifa University, PO Box 127788, Abu Dhabi (United Arab Emirates); Farhat, Ilyas A.H., E-mail: ilyas.farhat@outlook.com [Department of Applied Mathematics and Sciences, Khalifa University, PO Box 127788, Abu Dhabi (United Arab Emirates); Alhussein, Ghada, E-mail: ghada.alhussein@kustar.ac.ae [Department of Biomedical Engineering, Khalifa University, PO Box 127788, Abu Dhabi (United Arab Emirates); Christoforou, Nicolas, E-mail: nicolas.christoforou@kustar.ac.ae [Department of Biomedical Engineering, Khalifa University, PO Box 127788, Abu Dhabi (United Arab Emirates); Department of Biomedical Engineering, Duke University, Durham, NC 27708 (United States); Teo, Jeremy C.M., E-mail: jeremy.teo@kustar.ac.ae [Department of Biomedical Engineering, Khalifa University, PO Box 127788, Abu Dhabi (United Arab Emirates)

    2016-05-01

    In vitro research on vascular tissue engineering has extensively used isolated primary human or animal smooth muscle cells (SMC). Research programs that lack such facilities tend towards commercially available primary cells sources. Here, we aim to evaluate the capacity of commercially available human SMC to maintain their contractile phenotype, and determine if dedifferentiation towards the synthetic phenotype occurs in response to conventional cell culture and passaging without any external biochemical or mechanical stimuli. Lower passage SMC adopted a contractile phenotype marked by a relatively slower proliferation rate, higher expression of proteins of the contractile apparatus and smoothelin, elongated morphology, and reduced deposition of collagen types I and III. As the passage number increased, migratory capacity was enhanced, average cell speed, total distance and net distance travelled increased up to passage 8. Through the various assays, corroborative evidence pinpoints SMC at passage 7 as the transition point between the contractile and synthetic phenotypes, while passage 8 distinctly and consistently exhibited characteristics of synthetic phenotype. This knowledge is particularly useful in selecting SMC of appropriate passage number for the target vascular tissue engineering application, for example, a homeostatic vascular graft for blood vessel replacement versus recreating atherosclerotic blood vessel model in vitro. - Highlights: • Ability of human smooth muscle cells to alter phenotype in culture is evaluated. • Examined the effect of passaging human smooth muscle cells on phenotype. • Phenotype is assessed based on morphology, proliferation, markers, and migration. • Multi-resolution assessment methodology, single-cell and cell-population. • Lower and higher passages than P7 adopted a contractile and synthetic phenotype respectively.

  3. In-depth evaluation of commercially available human vascular smooth muscle cells phenotype: Implications for vascular tissue engineering

    International Nuclear Information System (INIS)

    Timraz, Sara B.H.; Farhat, Ilyas A.H.; Alhussein, Ghada; Christoforou, Nicolas; Teo, Jeremy C.M.

    2016-01-01

    In vitro research on vascular tissue engineering has extensively used isolated primary human or animal smooth muscle cells (SMC). Research programs that lack such facilities tend towards commercially available primary cells sources. Here, we aim to evaluate the capacity of commercially available human SMC to maintain their contractile phenotype, and determine if dedifferentiation towards the synthetic phenotype occurs in response to conventional cell culture and passaging without any external biochemical or mechanical stimuli. Lower passage SMC adopted a contractile phenotype marked by a relatively slower proliferation rate, higher expression of proteins of the contractile apparatus and smoothelin, elongated morphology, and reduced deposition of collagen types I and III. As the passage number increased, migratory capacity was enhanced, average cell speed, total distance and net distance travelled increased up to passage 8. Through the various assays, corroborative evidence pinpoints SMC at passage 7 as the transition point between the contractile and synthetic phenotypes, while passage 8 distinctly and consistently exhibited characteristics of synthetic phenotype. This knowledge is particularly useful in selecting SMC of appropriate passage number for the target vascular tissue engineering application, for example, a homeostatic vascular graft for blood vessel replacement versus recreating atherosclerotic blood vessel model in vitro. - Highlights: • Ability of human smooth muscle cells to alter phenotype in culture is evaluated. • Examined the effect of passaging human smooth muscle cells on phenotype. • Phenotype is assessed based on morphology, proliferation, markers, and migration. • Multi-resolution assessment methodology, single-cell and cell-population. • Lower and higher passages than P7 adopted a contractile and synthetic phenotype respectively.

  4. Urea immunoliposome inhibits human vascular endothelial cell proliferation for hemangioma treatment

    Science.gov (United States)

    2013-01-01

    Background Urea injection has been used in hemangioma treatment as sclerotherapy. It shrinks vascular endothelial cells and induces degeneration, necrosis, and fibrosis. However, this treatment still has disadvantages, such as lacking targeting and difficulty in controlling the urea dosage. Thus, we designed a urea immunoliposome to improve the efficiency of treatment. Methods The urea liposome was prepared by reverse phase evaporation. Furthermore, the urea immunoliposome was generated by coupling the urea liposome with a vascular endothelial growth factor receptor (VEGFR) monoclonal antibody using the glutaraldehyde cross-linking method. The influence of the urea immunoliposome on cultured human hemangioma vascular endothelial cells was observed preliminarily. Results Urea immunoliposomes showed typical liposome morphology under a transmission electron microscope, with an encapsulation percentage of 54.4% and a coupling rate of 36.84% for anti-VEGFR. Treatment with the urea immunoliposome significantly inhibited the proliferation of hemangioma vascular endothelial cells (HVECs) in a time- and dose-dependent manner. Conclusions The urea immunoliposome that we developed distinctly and persistently inhibited the proliferation of HVECs and is expected to be used in clinical hemangioma treatment. PMID:24266957

  5. History of Bioelectrical Study and the Electrophysiology of the Primo Vascular System

    Directory of Open Access Journals (Sweden)

    Sang Hyun Park

    2013-01-01

    Full Text Available Background. Primo vascular system is a new anatomical structure whose research results have reported the possibility of a new circulatory system similar to the blood vascular system and cells. Electrophysiology, which measures and analyzes bioelectrical signals tissues and cells, is an important research area for investigating the function of tissues and cells. The bioelectrical study of the primo vascular system has been reported by using modern techniques since the early 1960s by Bonghan Kim. This paper reviews the research result of the electrophysiological study of the primo vascular system for the discussion of the circulatory function. We hope it would help to study the electrophysiology of the primo vascular system for researchers. This paper will use the following exchangeable expressions: Kyungrak system = Bonghan system = Bonghan circulatory system = primo vascular system = primo system; Bonghan corpuscle = primo node; Bonghan duct = primo vessel. We think that objective descriptions of reviewed papers are more important than unified expressions when citing the papers. That said, this paper will unify the expressions of the primo vascular system.

  6. CCR7 signaling pathway and retinal neovascularization

    Directory of Open Access Journals (Sweden)

    Lin-Hui Yuan

    2015-11-01

    Full Text Available Retinal neovascularization diseases are the major causes of blindness. C-C chemokine receptor type 7(CCR7can promote the expression of vascular endothelial growth factor(VEGFthrough the extracellular signal regulated kinase(ERKpathway, leading to vascular leakage, proliferation of vascular endothelial cell, neovascularization and etc. The detection of CCR7 can guide the diagnosis and treatments of retinal neovascularization diseases.

  7. Influence of Androgen Receptor in Vascular Cells on Reperfusion following Hindlimb Ischaemia.

    Directory of Open Access Journals (Sweden)

    Junxi Wu

    Full Text Available Studies in global androgen receptor knockout (G-ARKO and orchidectomised mice suggest that androgen accelerates reperfusion of the ischaemic hindlimb by stimulating angiogenesis. This investigation used novel, vascular cell-specific ARKO mice to address the hypothesis that the impaired hindlimb reperfusion in G-ARKO mice was due to loss of AR from cells in the vascular wall.Mice with selective deletion of AR (ARKO from vascular smooth muscle cells (SM-ARKO, endothelial cells (VE-ARKO, or both (SM/VE-ARKO were compared with wild type (WT controls. Hindlimb ischaemia was induced in these mice by ligation and removal of the femoral artery. Post-operative reperfusion was reduced in SM-ARKO and SM/VE-ARKO mice. Immunohistochemistry indicated that this was accompanied by a reduced density of smooth muscle actin-positive vessels but no change in the density of isolectin B4-positive vessels in the gastrocnemius muscle. Deletion of AR from the endothelium (VE-ARKO did not alter post-operative reperfusion or vessel density. In an ex vivo (aortic ring culture model of angiogenesis, AR was not detected in vascular outgrowths and angiogenesis was not altered by vascular ARKO or by exposure to dihydrotestosterone (DHT 10-10-10-7M; 6 days.These results suggest that loss of AR from vascular smooth muscle, but not from the endothelium, contributes to impaired reperfusion in the ischaemic hindlimb of G-ARKO. Impaired reperfusion was associated with reduced collateral formation rather than reduced angiogenesis.

  8. The hemodynamically-regulated vascular microenvironment promotes migration of the steroidogenic tissue during its interaction with chromaffin cells in the zebrafish embryo.

    Directory of Open Access Journals (Sweden)

    Chih-Wei Chou

    Full Text Available BACKGROUND: While the endothelium-organ interaction is critical for regulating cellular behaviors during development and disease, the role of blood flow in these processes is only partially understood. The dorsal aorta performs paracrine functions for the timely migration and differentiation of the sympatho-adrenal system. However, it is unclear how the adrenal cortex and medulla achieve and maintain specific integration and whether hemodynamic forces play a role. METHODOLOGY AND PRINCIPAL FINDINGS: In this study, the possible modulation of steroidogenic and chromaffin cell integration by blood flow was investigated in the teleostean counterpart of the adrenal gland, the interrenal gland, in the zebrafish (Danio rerio. Steroidogenic tissue migration and angiogenesis were suppressed by genetic or pharmacologic inhibition of blood flow, and enhanced by acceleration of blood flow upon norepinephrine treatment. Repressed steroidogenic tissue migration and angiogenesis due to flow deficiency were recoverable following restoration of flow. The regulation of interrenal morphogenesis by blood flow was found to be mediated through the vascular microenvironment and the Fibronectin-phosphorylated Focal Adhesion Kinase (Fn-pFak signaling. Moreover, the knockdown of krüppel-like factor 2a (klf2a or matrix metalloproteinase 2 (mmp2, two genes regulated by the hemodynamic force, phenocopied the defects in migration, angiogenesis, the vascular microenvironment, and pFak signaling of the steroidogenic tissue observed in flow-deficient embryos, indicating a direct requirement of mechanotransduction in these processes. Interestingly, epithelial-type steroidogenic cells assumed a mesenchymal-like character and downregulated β-Catenin at cell-cell junctions during interaction with chromaffin cells, which was reversed by inhibiting blood flow or Fn-pFak signaling. Blood flow obstruction also affected the migration of chromaffin cells, but not through

  9. Vascular Remodelling and Mesenchymal Transition in Systemic Sclerosis

    Directory of Open Access Journals (Sweden)

    Pier Andrea Nicolosi

    2016-01-01

    Full Text Available Fibrosis of the skin and of internal organs, autoimmunity, and vascular inflammation are hallmarks of Systemic Sclerosis (SSc. The injury and activation of endothelial cells, with hyperplasia of the intima and eventual obliteration of the vascular lumen, are early features of SSc. Reduced capillary blood flow coupled with deficient angiogenesis leads to chronic hypoxia and tissue ischemia, enforcing a positive feed-forward loop sustaining vascular remodelling, further exacerbated by extracellular matrix accumulation due to fibrosis. Despite numerous developments and a growing number of controlled clinical trials no treatment has been shown so far to alter SSc natural history, outlining the need of further investigation in the molecular pathways involved in the pathogenesis of the disease. We review some processes potentially involved in SSc vasculopathy, with attention to the possible effect of sustained vascular inflammation on the plasticity of vascular cells. Specifically we focus on mesenchymal transition, a key phenomenon in the cardiac and vascular development as well as in the remodelling of injured vessels. Recent work supports the role of transforming growth factor-beta, Wnt, and Notch signaling in these processes. Importantly, endothelial-mesenchymal transition may be reversible, possibly offering novel cues for treatment.

  10. Enhanced elastin synthesis and maturation in human vascular smooth muscle tissue derived from induced-pluripotent stem cells.

    Science.gov (United States)

    Eoh, Joon H; Shen, Nian; Burke, Jacqueline A; Hinderer, Svenja; Xia, Zhiyong; Schenke-Layland, Katja; Gerecht, Sharon

    2017-04-01

    Obtaining vascular smooth muscle tissue with mature, functional elastic fibers is a key obstacle in tissue-engineered blood vessels. Poor elastin secretion and organization leads to a loss of specialization in contractile smooth muscle cells, resulting in over proliferation and graft failure. In this study, human induced-pluripotent stem cells (hiPSCs) were differentiated into early smooth muscle cells, seeded onto a hybrid poly(ethylene glycol) dimethacrylate/poly (l-lactide) (PEGdma-PLA) scaffold and cultured in a bioreactor while exposed to pulsatile flow, towards maturation into contractile smooth muscle tissue. We evaluated the effects of pulsatile flow on cellular organization as well as elastin expression and assembly in the engineered tissue compared to a static control through immunohistochemistry, gene expression and functionality assays. We show that culturing under pulsatile flow resulted in organized and functional hiPSC derived smooth muscle tissue. Immunohistochemistry analysis revealed hiPSC-smooth muscle tissue with robust, well-organized cells and elastic fibers and the supporting microfibril proteins necessary for elastic fiber assembly. Through qRT-PCR analysis, we found significantly increased expression of elastin, fibronectin, and collagen I, indicating the synthesis of necessary extracellular matrix components. Functionality assays revealed that hiPSC-smooth muscle tissue cultured in the bioreactor had an increased calcium signaling and contraction in response to a cholinergic agonist, significantly higher mature elastin content and improved mechanical properties in comparison to the static control. The findings presented here detail an effective approach to engineering elastic human vascular smooth muscle tissue with the functionality necessary for tissue engineering and regenerative medicine applications. Obtaining robust, mature elastic fibers is a key obstacle in tissue-engineered blood vessels. Human induced-pluripotent stem cells have

  11. Hematopoietic stem cell capture and directional differentiation into vascular endothelial cells for metal stent-coated chitosan/hyaluronic acid loading CD133 antibody.

    Science.gov (United States)

    Zhang, Shixuan; Zhang, Fan; Feng, Bo; Fan, Qingyu; Yang, Feng; Shang, Debin; Sui, Jinghan; Zhao, Hong

    2015-03-01

    A series of metal stents coated with chitosan/hyaluronic acid (CS/HA) loading antibodies by electrostatic self-assembled method were prepared, and the types of cells captured by antibodies and their differentiation in vascular endothelial cells (ECs) evaluated by molecular biology and scanning electron microscope. The results showed that CD133 stent can selectively capture hematopoietic stem cells (HSC),which directionally differentiate into vascular ECs in peripheral blood by (CS/HA) induction, and simultaneously inhibit migration and proliferation of immune cells and vascular smooth muscle cells (MCs). CD34 stent can capture HSC, hematopoietic progenitor cells that differentiate into vascular ECs and immune cells, promoting smooth MCs growth, leading to thrombosis, inflammation, and rejection. CD133 stent can be implanted into miniature pig heart coronary and can repair vascular damage by capturing own HSC, thus contributing to the rapid natural vascular repair, avoiding inflammation and rejection, thrombosis and restenosis. These studies demonstrated that CD133 stent of HSC capture will be an ideal coated metal stent providing a new therapeutic approach for cardiovascular and cerebrovascular disease.

  12. Vascular endothelial growth factor receptor-1 mediates migration of human colorectal carcinoma cells by activation of Src family kinases

    Science.gov (United States)

    Lesslie, D P; Summy, J M; Parikh, N U; Fan, F; Trevino, J G; Sawyer, T K; Metcalf, C A; Shakespeare, W C; Hicklin, D J; Ellis, L M; Gallick, G E

    2006-01-01

    Vascular endothelial growth factor (VEGF) is the predominant pro-angiogenic cytokine in human malignancy, and its expression correlates with disease recurrence and poor outcomes in patients with colorectal cancer. Recently, expression of vascular endothelial growth factor receptors (VEGFRs) has been observed on tumours of epithelial origin, including those arising in the colon, but the molecular mechanisms governing potential VEGF-driven biologic functioning in these tumours are not well characterised. In this report, we investigated the role of Src family kinases (SFKs) in VEGF-mediated signalling in human colorectal carcinoma (CRC) cell lines. Vascular endothelial growth factor specifically activated SFKs in HT29 and KM12L4 CRC cell lines. Further, VEGF stimulation resulted in enhanced cellular migration, which was effectively blocked by pharmacologic inhibition of VEGFR-1 or Src kinase. Correspondingly, migration studies using siRNA clones with reduced Src expression confirmed the requirement for Src in VEGF-induced migration in these cells. Furthermore, VEGF treatment enhanced VEGFR-1/SFK complex formation and increased tyrosine phosphorylation of focal adhesion kinase, p130 cas and paxillin. Finally, we demonstrate that VEGF-induced migration is not due, at least in part, to VEGF acting as a mitogen. These results suggest that VEGFR-1 promotes migration of tumour cells through a Src-dependent pathway linked to activation of focal adhesion components that regulate this process. PMID:16685275

  13. Tissue-engineered vascular grafts for use in the treatment of congenital heart disease: from the bench to the clinic and back again.

    Science.gov (United States)

    Patterson, Joseph T; Gilliland, Thomas; Maxfield, Mark W; Church, Spencer; Naito, Yuji; Shinoka, Toshiharu; Breuer, Christopher K

    2012-05-01

    Since the first tissue-engineered vascular graft (TEVG) was implanted in a child over a decade ago, growth in the field of vascular tissue engineering has been driven by clinical demand for improved vascular prostheses with performance and durability similar to an autologous blood vessel. Great strides were made in pediatric congenital heart surgery using the classical tissue engineering paradigm, and cell seeding of scaffolds in vitro remained the cornerstone of neotissue formation. Our second-generation bone marrow cell-seeded TEVG diverged from tissue engineering dogma with a design that induces the recipient to regenerate vascular tissue in situ. New insights suggest that neovessel development is guided by cell signals derived from both seeded cells and host inflammatory cells that infiltrate the graft. The identification of these signals and the regulatory interactions that influence cell migration, phenotype and extracellular matrix deposition during TEVG remodeling are yielding a next-generation TEVG engineered to guide neotissue regeneration without the use of seeded cells. These developments represent steady progress towards our goal of an off-the-shelf tissue-engineered vascular conduit for pediatric congenital heart surgery.

  14. Tissue-Engineered Vascular Rings from Human iPSC-Derived Smooth Muscle Cells

    Directory of Open Access Journals (Sweden)

    Biraja C. Dash

    2016-07-01

    Full Text Available There is an urgent need for an efficient approach to obtain a large-scale and renewable source of functional human vascular smooth muscle cells (VSMCs to establish robust, patient-specific tissue model systems for studying the pathogenesis of vascular disease, and for developing novel therapeutic interventions. Here, we have derived a large quantity of highly enriched functional VSMCs from human induced pluripotent stem cells (hiPSC-VSMCs. Furthermore, we have engineered 3D tissue rings from hiPSC-VSMCs using a facile one-step cellular self-assembly approach. The tissue rings are mechanically robust and can be used for vascular tissue engineering and disease modeling of supravalvular aortic stenosis syndrome. Our method may serve as a model system, extendable to study other vascular proliferative diseases for drug screening. Thus, this report describes an exciting platform technology with broad utility for manufacturing cell-based tissues and materials for various biomedical applications.

  15. Delayed effects of cold atmospheric plasma on vascular cells

    NARCIS (Netherlands)

    Stoffels, Eva; Roks, Anton J. M.; Deelmm, Leo E.

    2008-01-01

    We investigated the long-term behaviour of vascular cells (endothelial and smooth muscle) after exposure to a cold atmospheric plasma source. The cells were treated through a gas-permeable membrane, in order to simulate intravenous treatment with a gas plasma-filled catheter. Such indirect treatment

  16. The redox mechanism for vascular barrier dysfunction associated with metabolic disorders: Glutathionylation of Rac1 in endothelial cells.

    Science.gov (United States)

    Han, Jingyan; Weisbrod, Robert M; Shao, Di; Watanabe, Yosuke; Yin, Xiaoyan; Bachschmid, Markus M; Seta, Francesca; Janssen-Heininger, Yvonne M W; Matsui, Reiko; Zang, Mengwei; Hamburg, Naomi M; Cohen, Richard A

    2016-10-01

    Oxidative stress is implicated in increased vascular permeability associated with metabolic disorders, but the underlying redox mechanism is poorly defined. S-glutathionylation, a stable adduct of glutathione with protein sulfhydryl, is a reversible oxidative modification of protein and is emerging as an important redox signaling paradigm in cardiovascular physiopathology. The present study determines the role of protein S-glutathionylation in metabolic stress-induced endothelial cell permeability. In endothelial cells isolated from patients with type-2 diabetes mellitus, protein S-glutathionylation level was increased. This change was also observed in aortic endothelium in ApoE deficient (ApoE -/- ) mice fed on Western diet. Metabolic stress-induced protein S-glutathionylation in human aortic endothelial cells (HAEC) was positively correlated with elevated endothelial cell permeability, as reflected by disassembly of cell-cell adherens junctions and cortical actin structures. These impairments were reversed by adenoviral overexpression of a specific de-glutathionylation enzyme, glutaredoxin-1 in cultured HAECs. Consistently, transgenic overexpression of human Glrx-1 in ApoE -/- mice fed the Western diet attenuated endothelial protein S-glutathionylation, actin cytoskeletal disorganization, and vascular permeability in the aorta. Mechanistically, glutathionylation and inactivation of Rac1, a small RhoGPase, were associated with endothelial hyperpermeability caused by metabolic stress. Glutathionylation of Rac1 on cysteine 81 and 157 located adjacent to guanine nucleotide binding site was required for the metabolic stress to inhibit Rac1 activity and promote endothelial hyperpermeability. Glutathionylation and inactivation of Rac1 in endothelial cells represent a novel redox mechanism of vascular barrier dysfunction associated with metabolic disorders. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

  17. Vascular Endothelial Growth Factor Receptor 3 Controls Neural Stem Cell Activation in Mice and Humans

    Directory of Open Access Journals (Sweden)

    Jinah Han

    2015-02-01

    Full Text Available Neural stem cells (NSCs continuously produce new neurons within the adult mammalian hippocampus. NSCs are typically quiescent but activated to self-renew or differentiate into neural progenitor cells. The molecular mechanisms of NSC activation remain poorly understood. Here, we show that adult hippocampal NSCs express vascular endothelial growth factor receptor (VEGFR 3 and its ligand VEGF-C, which activates quiescent NSCs to enter the cell cycle and generate progenitor cells. Hippocampal NSC activation and neurogenesis are impaired by conditional deletion of Vegfr3 in NSCs. Functionally, this is associated with compromised NSC activation in response to VEGF-C and physical activity. In NSCs derived from human embryonic stem cells (hESCs, VEGF-C/VEGFR3 mediates intracellular activation of AKT and ERK pathways that control cell fate and proliferation. These findings identify VEGF-C/VEGFR3 signaling as a specific regulator of NSC activation and neurogenesis in mammals.

  18. VEGFR2 Trafficking, Signaling and Proteolysis is Regulated by the Ubiquitin Isopeptidase USP8.

    Science.gov (United States)

    Smith, Gina A; Fearnley, Gareth W; Abdul-Zani, Izma; Wheatcroft, Stephen B; Tomlinson, Darren C; Harrison, Michael A; Ponnambalam, Sreenivasan

    2016-01-01

    Vascular endothelial growth factor A (VEGF-A) regulates many aspects of vascular function. VEGF-A binding to vascular endothelial growth factor receptor 2 (VEGFR2) stimulates endothelial signal transduction and regulates multiple cellular responses. Activated VEGFR2 undergoes ubiquitination but the enzymes that regulate this post-translational modification are unclear. In this study, the de-ubiquitinating enzyme, USP8, is shown to regulate VEGFR2 trafficking, de-ubiquitination, proteolysis and signal transduction. USP8-depleted endothelial cells displayed altered VEGFR2 ubiquitination and production of a unique VEGFR2 extracellular domain proteolytic fragment caused by VEGFR2 accumulation in the endosome-lysosome system. In addition, perturbed VEGFR2 trafficking impaired VEGF-A-stimulated signal transduction in USP8-depleted cells. Thus, regulation of VEGFR2 ubiquitination and de-ubiquitination has important consequences for the endothelial cell response and vascular physiology. © 2015 The Authors. Traffic published by John Wiley & Sons Ltd.

  19. Three-Dimensional Vascular Network Assembly From Diabetic Patient-Derived Induced Pluripotent Stem Cells.

    Science.gov (United States)

    Chan, Xin Yi; Black, Rebecca; Dickerman, Kayla; Federico, Joseph; Lévesque, Mathieu; Mumm, Jeff; Gerecht, Sharon

    2015-12-01

    In diabetics, hyperglycemia results in deficient endothelial progenitors and cells, leading to cardiovascular complications. We aim to engineer 3-dimensional (3D) vascular networks in synthetic hydrogels from type 1 diabetes mellitus (T1D) patient-derived human-induced pluripotent stem cells (hiPSCs), to serve as a transformative autologous vascular therapy for diabetic patients. We validated and optimized an adherent, feeder-free differentiation procedure to derive early vascular cells (EVCs) with high portions of vascular endothelial cadherin-positive cells from hiPSCs. We demonstrate similar differentiation efficiency from hiPSCs derived from healthy donor and patients with T1D. T1D-hiPSC-derived vascular endothelial cadherin-positive cells can mature to functional endothelial cells-expressing mature markers: von Willebrand factor and endothelial nitric oxide synthase are capable of lectin binding and acetylated low-density lipoprotein uptake, form cords in Matrigel and respond to tumor necrosis factor-α. When embedded in engineered hyaluronic acid hydrogels, T1D-EVCs undergo morphogenesis and assemble into 3D networks. When encapsulated in a novel hypoxia-inducible hydrogel, T1D-EVCs respond to low oxygen and form 3D networks. As xenografts, T1D-EVCs incorporate into developing zebrafish vasculature. Using our robust protocol, we can direct efficient differentiation of T1D-hiPSC to EVCs. Early endothelial cells derived from T1D-hiPSC are functional when mature. T1D-EVCs self-assembled into 3D networks when embedded in hyaluronic acid and hypoxia-inducible hydrogels. The capability of T1D-EVCs to assemble into 3D networks in engineered matrices and to respond to a hypoxic microenvironment is a significant advancement for autologous vascular therapy in diabetic patients and has broad importance for tissue engineering. © 2015 American Heart Association, Inc.

  20. Src Kinase becomes preferentially associated with the VEGFR, KDR/Flk-1, following VEGF stimulation of vascular endothelial cells

    Directory of Open Access Journals (Sweden)

    Wang Jing

    2002-12-01

    Full Text Available Abstract Background The cytoplasmic tyrosine kinase, Src, has been found to play a crucial role in VEGF (vascular endothelial growth factor – dependent vascular permeability involved in angiogenesis. The two main VEGFRs present on vascular endothelial cells are KDR/Flk-1 (kinase insert domain-containing receptor/fetal liver kinase-1 and Flt-1 (Fms-like tyrosine kinase-1. However, to date, it has not been determined which VEGF receptor (VEGFR is involved in binding to and activating Src kinase following VEGF stimulation of the receptors. Results In this report, we demonstrate that Src preferentially associates with KDR/Flk-1 rather than Flt-1 in human umbilical vein endothelial cells (HUVECs, and that VEGF stimulation resulted in an increase of Src activity associated with activated KDR/Flk-1. These findings were determined through immunoprecipitation-kinase experiments and coimmunoprecipitation studies, and were further confirmed by GST-pull-down assays and Far Western studies. However, Fyn and Yes, unlike Src, were found to associate preferentially with Flt-1. Conclusions Thus, Src preferentially associates with KDR/Flk-1, rather than with Flt-1, upon VEGF stimulation in endothelial cells. Our findings further highlight the potential significance of upregulated KDR/Flk-1-associated Src activity in the process of angiogenesis, and help to elucidate more clearly the specific roles and mechanisms involving Src family tyrosine kinase in VEGF-stimulated signal transduction events.

  1. Obesity-induced vascular dysfunction and arterial stiffening requires endothelial cell arginase 1.

    Science.gov (United States)

    Bhatta, Anil; Yao, Lin; Xu, Zhimin; Toque, Haroldo A; Chen, Jijun; Atawia, Reem T; Fouda, Abdelrahman Y; Bagi, Zsolt; Lucas, Rudolf; Caldwell, Ruth B; Caldwell, Robert W

    2017-11-01

    Elevation of arginase activity has been linked to vascular dysfunction in diabetes and hypertension by a mechanism involving decreased nitric oxide (NO) bioavailability due to L-arginine depletion. Excessive arginase activity also can drive L-arginine metabolism towards the production of ornithine, polyamines, and proline, promoting proliferation of vascular smooth muscle cells and collagen formation, leading to perivascular fibrosis. We hypothesized that there is a specific involvement of arginase 1 expression within the vascular endothelial cells in this pathology. To test this proposition, we used models of type 2 diabetes and metabolic syndrome. Studies were performed using wild type (WT), endothelial-specific arginase 1 knockout (EC-A1-/-) and littermate controls(A1con) mice fed high fat-high sucrose (HFHS) or normal diet (ND) for 6 months and isolated vessels exposed to palmitate-high glucose (PA/HG) media. Some WT mice or isolated vessels were treated with an arginase inhibitor, ABH [2-(S)-amino-6-boronohexanoic acid. In WT mice, the HFHS diet promoted increases in body weight, fasting blood glucose, and post-prandial insulin levels along with arterial stiffening and fibrosis, elevated blood pressure, decreased plasma levels of L-arginine, and elevated L-ornithine. The HFHS diet or PA/HG treatment also induced increases in vascular arginase activity along with oxidative stress, reduced vascular NO levels, and impaired endothelial-dependent vasorelaxation. All of these effects except obesity and hypercholesterolemia were prevented or significantly reduced by endothelial-specific deletion of arginase 1 or ABH treatment. Vascular dysfunctions in diet-induced obesity are prevented by deletion of arginase 1 in vascular endothelial cells or arginase inhibition. These findings indicate that upregulation of arginase 1 expression/activity in vascular endothelial cells has an integral role in diet-induced cardiovascular dysfunction and metabolic syndrome. Published

  2. Angiotensin II modulates interleukin-1β-induced inflammatory gene expression in vascular smooth muscle cells via interfering with ERK-NF-κB crosstalk

    International Nuclear Information System (INIS)

    Xu, Shanqin; Zhi, Hui; Hou, Xiuyun; Jiang, Bingbing

    2011-01-01

    Highlights: → We examine how angiotensin II modulates ERK-NF-κB crosstalk and gene expression. → Angiotensin II suppresses IL-1β-induced prolonged ERK and NF-κB activation. → ERK-RSK1 signaling is required for IL-1β-induced prolonged NF-κB activation. → Angiotensin II modulates NF-κB responsive genes via regulating ERK-NF-κB crosstalk. → ERK-NF-κB crosstalk is a novel mechanism regulating inflammatory gene expression. -- Abstract: Angiotensin II is implicated in cardiovascular diseases, which is associated with a role in increasing vascular inflammation. The present study investigated how angiotensin II modulates vascular inflammatory signaling and expression of inducible nitric oxide synthase (iNOS) and vascular cell adhesion molecule (VCAM)-1. In cultured rat aortic vascular smooth muscle cells (VSMCs), angiotensin II suppressed interleukin-1β-induced prolonged phosphorylation of extracellular signal-regulated kinase (ERK) and ribosomal S6 kinase (RSK)-1, and nuclear translocation of nuclear factor (NF)-κB, leading to decreased iNOS but enhanced VCAM-1 expression, associated with an up-regulation of mitogen-activated protein kinase phosphatase-1 expression. Knock-down of RSK1 selectively down regulated interleukin-1β-induced iNOS expression without influencing VCAM-1 expression. In vivo experiments showed that interleukin-1β, iNOS, and VCAM-1 expression were detectable in the aortic arches of both wild-type and apolipoprotein E-deficient (ApoE -/- ) mice. VCAM-1 and iNOS expression were higher in ApoE -/- than in wild type mouse aortic arches. Angiotensin II infusion (3.2 mg/kg/day, for 6 days, via subcutaneous osmotic pump) in ApoE -/- mice enhanced endothelial and adventitial VCAM-1 and iNOS expression, but reduced medial smooth muscle iNOS expression associated with reduced phosphorylation of ERK and RSK-1. These results indicate that angiotensin II can differentially modulate inflammatory gene expression in aortic smooth muscle cells

  3. Isolation and differentiation of stromal vascular cells to beige/brite cells

    DEFF Research Database (Denmark)

    Aune, Ulrike Liisberg; Ruiz, Lauren; Kajimura, Shingo

    2013-01-01

    cold exposure or by PPARγ agonists, therefore, this cell type has potential as a therapeutic target for obesity treatment. Although most immortalized adipocyte lines cannot recapitulate the process of "browning" of white fat in culture, primary adipocytes isolated from stromal vascular fraction...

  4. Upregulation of Klotho potentially inhibits pulmonary vascular remodeling by blocking the activation of the Wnt signaling pathway in rats with PM2.5-induced pulmonary arterial hypertension.

    Science.gov (United States)

    Cong, Lu-Hong; Du, Shi-Yu; Wu, Yi-Na; Liu, Ying; Li, Tao; Wang, Hui; Li, Gang; Duan, Jun

    2018-01-30

    We evaluated the effects of Klotho on pulmonary vascular remodeling and cell proliferation and apoptosis in rat models with PM2.5-induced pulmonary arterial hypertension (PAH) via the Wnt signaling pathway. After establishing rat models of PM2.5-induced PAH, these Sprague-Dawley male rats were randomized into control and model groups. Cells extracted from the model rats were sub-categorized into different groups. Activation of Wnt/β-catenin signaling transcription factor was detected by a TOPFlash/FOPFlash assay. A serial of experiment was conducted to identify the mechanism of Klotho on PHA via the Wnt signaling pathway. VEGF levels and PaCO 2 content were higher in the model group, while PaO 2, NO 2 - /NO 3 - content and Klotho level was lower compared to the control group. In comparison to the control group, the model group had decreased Klotho and Bax levels, and elevated Wnt-1, β-catenin, bcl-2, survivin, and PCNA expression, VEGF, IL-6, TNF-α, TNF-β1, and bFGF levels, as well as the percentage of pulmonary artery ring contraction. The Klotho vector, DKK-1 and DKK-1 + Klotho vector groups exhibited reduced cell proliferation, luciferase activity, and the expression of Wnt-1, β-catenin, bcl-2, survivin, and PCNA, as well as shortened S phase compared with the blank and NC groups. Compared with the Klotho vector and DKK-1 groups, the DKK-1 + Klotho vector groups had reduced cell proliferation, luciferase activity, and the expression of Wnt-1, β-catenin, bcl-2, survivin, and PCNA, as well as a shortened S phase. Conclusively, Klotho inhibits pulmonary vascular remodeling by inactivation of Wnt signaling pathway. © 2018 Wiley Periodicals, Inc.

  5. Pancreatic endoplasmic reticulum kinase activation promotes medulloblastoma cell migration and invasion through induction of vascular endothelial growth factor A.

    Directory of Open Access Journals (Sweden)

    Stephanie Jamison

    Full Text Available Evidence is accumulating that activation of the pancreatic endoplasmic reticulum kinase (PERK in response to endoplasmic reticulum (ER stress adapts tumor cells to the tumor microenvironment and enhances tumor angiogenesis by inducing vascular endothelial growth factor A (VEGF-A. Recent studies suggest that VEGF-A can act directly on certain tumor cell types in an autocrine manner, via binding to VEGF receptor 2 (VEGFR2, to promote tumor cell migration and invasion. Although several reports show that PERK activation increases VEGF-A expression in medulloblastoma, the most common solid malignancy of childhood, the role that either PERK or VEGF-A plays in medulloblastoma remains elusive. In this study, we mimicked the moderate enhancement of PERK activity observed in tumor patients using a genetic approach and a pharmacologic approach, and found that moderate activation of PERK signaling facilitated medulloblastoma cell migration and invasion and increased the production of VEGF-A. Moreover, using the VEGFR2 inhibitor SU5416 and the VEGF-A neutralizing antibody to block VEGF-A/VEGFR2 signaling, our results suggested that tumor cell-derived VEGF-A promoted medulloblastoma cell migration and invasion through VEGFR2 signaling, and that both VEGF-A and VEGFR2 were required for the promoting effects of PERK activation on medulloblastoma cell migration and invasion. Thus, these findings suggest that moderate PERK activation promotes medulloblastoma cell migration and invasion through enhancement of VEGF-A/VEGFR2 signaling.

  6. Stem Cells on Biomaterials for Synthetic Grafts to Promote Vascular Healing

    Science.gov (United States)

    Babczyk, Patrick; Conzendorf, Clelia; Klose, Jens; Schulze, Margit; Harre, Kathrin; Tobiasch, Edda

    2014-01-01

    This review is divided into two interconnected parts, namely a biological and a chemical one. The focus of the first part is on the biological background for constructing tissue-engineered vascular grafts to promote vascular healing. Various cell types, such as embryonic, mesenchymal and induced pluripotent stem cells, progenitor cells and endothelial- and smooth muscle cells will be discussed with respect to their specific markers. The in vitro and in vivo models and their potential to treat vascular diseases are also introduced. The chemical part focuses on strategies using either artificial or natural polymers for scaffold fabrication, including decellularized cardiovascular tissue. An overview will be given on scaffold fabrication including conventional methods and nanotechnologies. Special attention is given to 3D network formation via different chemical and physical cross-linking methods. In particular, electron beam treatment is introduced as a method to combine 3D network formation and surface modification. The review includes recently published scientific data and patents which have been registered within the last decade. PMID:26237251

  7. A pro-inflammatory role of deubiquitinating enzyme cylindromatosis (CYLD) in vascular smooth muscle cells

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Shuai [Shandong University Qilu Hospital Research Center for Cell Therapy, Key Laboratory of Cardiovascular Remodeling and Function Research, Qilu Hospital of Shandong University, Jinan 250012 (China); Department of Cell Biology and Anatomy, University of South Carolina School of Medicine, Columbia, SC 29208 (United States); Lv, Jiaju [Department of Urology, Shandong Provincial Hospital, Shandong University, Jinan 250021 (China); Han, Liping; Ichikawa, Tomonaga; Wang, Wenjuan; Li, Siying [Department of Cell Biology and Anatomy, University of South Carolina School of Medicine, Columbia, SC 29208 (United States); Wang, Xing Li [Shandong University Qilu Hospital Research Center for Cell Therapy, Key Laboratory of Cardiovascular Remodeling and Function Research, Qilu Hospital of Shandong University, Jinan 250012 (China); Tang, Dongqi, E-mail: tangdq@pathology.ufl.edu [Department of Pathology, Immunology, and Laboratory Medicine, University of Florida College of Medicine, Gainesville, FL 32610-0275 (United States); Cui, Taixing, E-mail: taixing.cui@uscmed.sc.edu [Department of Cell Biology and Anatomy, University of South Carolina School of Medicine, Columbia, SC 29208 (United States)

    2012-03-30

    Highlights: Black-Right-Pointing-Pointer Cyld deficiency suppresses pro-inflammatory phenotypic switch of VSMCs. Black-Right-Pointing-Pointer Cyld deficiency inhibits MAPK rather than NF-kB activity in inflamed VSMCs. Black-Right-Pointing-Pointer CYLD is up-regulated in the coronary artery with neointimal hyperplasia. -- Abstract: CYLD, a deubiquitinating enzyme (DUB), is a critical regulator of diverse cellular processes, ranging from proliferation and differentiation to inflammatory responses, via regulating multiple key signaling cascades such as nuclear factor kappa B (NF-{kappa}B) pathway. CYLD has been shown to inhibit vascular lesion formation presumably through suppressing NF-{kappa}B activity in vascular cells. However, herein we report a novel role of CYLD in mediating pro-inflammatory responses in vascular smooth muscle cells (VSMCs) via a mechanism independent of NF-{kappa}B activity. Adenoviral knockdown of Cyld inhibited basal and the tumor necrosis factor alpha (TNF{alpha})-induced mRNA expression of pro-inflammatory cytokines including monocyte chemotactic protein-1 (Mcp-1), intercellular adhesion molecule (Icam-1) and interleukin-6 (Il-6) in rat adult aortic SMCs (RASMCs). The CYLD deficiency led to increases in the basal NF-{kappa}B transcriptional activity in RASMCs; however, did not affect the TNF{alpha}-induced NF-{kappa}B activity. Intriguingly, the TNF{alpha}-induced I{kappa}B phosphorylation was enhanced in the CYLD deficient RASMCs. While knocking down of Cyld decreased slightly the basal expression levels of I{kappa}B{alpha} and I{kappa}B{beta} proteins, it did not alter the kinetics of TNF{alpha}-induced I{kappa}B protein degradation in RASMCs. These results indicate that CYLD suppresses the basal NF-{kappa}B activity and TNF{alpha}-induced I{kappa}B kinase activation without affecting TNF{alpha}-induced NF-{kappa}B activity in VSMCs. In addition, knocking down of Cyld suppressed TNF{alpha}-induced activation of mitogen activated protein

  8. Augmented vascular smooth muscle cell stiffness and adhesion when hypertension is superimposed on aging.

    Science.gov (United States)

    Sehgel, Nancy L; Sun, Zhe; Hong, Zhongkui; Hunter, William C; Hill, Michael A; Vatner, Dorothy E; Vatner, Stephen F; Meininger, Gerald A

    2015-02-01

    Hypertension and aging are both recognized to increase aortic stiffness, but their interactions are not completely understood. Most previous studies have attributed increased aortic stiffness to changes in extracellular matrix proteins that alter the mechanical properties of the vascular wall. Alternatively, we hypothesized that a significant component of increased vascular stiffness in hypertension is due to changes in the mechanical and adhesive properties of vascular smooth muscle cells, and that aging would augment the contribution from vascular smooth muscle cells when compared with the extracellular matrix. Accordingly, we studied aortic stiffness in young (16-week-old) and old (64-week-old) spontaneously hypertensive rats and Wistar-Kyoto wild-type controls. Systolic and pulse pressures were significantly increased in young spontaneously hypertensive rats when compared with young Wistar-Kyoto rats, and these continued to rise in old spontaneously hypertensive rats when compared with age-matched controls. Excised aortic ring segments exhibited significantly greater elastic moduli in both young and old spontaneously hypertensive rats versus Wistar-Kyoto rats. were isolated from the thoracic aorta, and stiffness and adhesion to fibronectin were measured by atomic force microscopy. Hypertension increased both vascular smooth muscle cell stiffness and vascular smooth muscle cell adhesion, and these increases were both augmented with aging. By contrast, hypertension did not affect histological measures of aortic collagen and elastin, which were predominantly changed by aging. These findings support the concept that stiffness and adhesive properties of vascular smooth muscle cells are novel mechanisms contributing to the increased aortic stiffness occurring with hypertension superimposed on aging. © 2014 American Heart Association, Inc.

  9. Inhibition of Epidermal Growth Factor Receptor and Vascular Endothelial Growth Factor Receptor Phosphorylation on Tumor-Associated Endothelial Cells Leads to Treatment of Orthotopic Human Colon Cancer in Nude Mice

    Directory of Open Access Journals (Sweden)

    Takamitsu Sasaki

    2007-12-01

    Full Text Available The purpose of our study was to determine whether the dual inhibition of epidermal growth factor receptor (EGFR and vascular endothelial growth factor receptor (VEGFR signaling pathways in tumor-associated endothelial cells can inhibit the progressive growth of human colon carcinoma in the cecum of nude mice. SW620CE2 human colon cancer cells growing in culture and orthotopically in the cecum of nude mice expressed a high level of transforming growth factor alpha (TGF-α and vascular endothelial growth factor (VEGF but were negative for EGFR, human epidermal growth factor receptor 2 (HER2, VEGFR. Double immunofluorescence staining revealed that tumorassociated endothelial cells expressed EGFR, VEGFR2, phosphorylated EGFR (pEGFR, phosphorylated VEGFR (pVEGFR. Treatment of mice with either 7H-pyrrolo [2,3-d]-pyrimidine lead scaffold (AEE788; an inhibitor of EGFR and VEGFR tyrosine kinase or CPT-11 as single agents significantly inhibited the growth of cecal tumors (P < .01; this decrease was even more pronounced with AEE788 combined with CPT-11 (P < .001. AEE788 alone or combined with CPT-11 also inhibited the expression of pEGFR and pVEGFR on tumor-associated endothelial cells, significantly decreased vascularization and tumor cell proliferation, increased the level of apoptosis in both tumorassociated endothelial cells and tumor cells. These data demonstrate that targeting EGFR and VEGFR signaling on tumor-associated endothelial cells provides a viable approach for the treatment of colon cancer.

  10. Anti-TNF-α activity of Portulaca oleracea in vascular endothelial cells.

    Science.gov (United States)

    Lee, An Sook; Kim, Jin Sook; Lee, Yun Jung; Kang, Dae Gill; Lee, Ho Sub

    2012-01-01

    Vascular inflammation plays a key role in the pathogenesis and progression of atherosclerosis, a main complication of diabetes. The present study investigated whether an aqueous extract of Portulaca oleracea (AP) prevents the TNF-α-induced vascular inflammatory process in the human umbilical vein endothelial cell (HUVEC). The stimulation of TNF-α induced overexpression of adhesion molecules affects vascular cell adhesion molecule (VCAM)-1, intercellular adhesion molecule (ICAM)-1 and E-selectin for example. However, AP significantly suppressed TNF-α-induced over-expression of these adhesion molecules in a dose-dependent manner. In addition, pretreatment with AP dose-dependently reduced an increase of the adhesion of HL-60 cells to TNF-α-induced HUVEC. Furthermore, we observed that stimulation of TNF-α significantly increased intracellular reactive oxygen species (ROS) production. However, pretreatment with AP markedly blocked TNF-α-induced ROS production in a dose-dependent manner. The western blot and immunofluorescence analysis showed that AP inhibited the translocation of p65 NF-κB to the nucleus. In addition, AP suppressed the TNF-α-induced degradation of IκB-α and attenuated the TNF-α-induced NF-κB binding. AP also effectively reduced TNF-α-induced mRNA expressions of monocyte chemoattractant protein (MCP)-1 and interleukin (IL)-8 in a dose-dependent manner. Taken together, AP prevents the vascular inflammatory process through the inhibition of intracellular ROS production and NF-κB activation as well as the reduction of adhesion molecule expression in TNF-α-induced HUVEC. These results suggested that AP might have a potential therapeutic effect by inhibiting the vascular inflammation process in vascular diseases such as atherosclerosis.

  11. Peptide-modified PELCL electrospun membranes for regulation of vascular endothelial cells

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    Zhou, Fang [School of Materials Science and Engineering, Tianjin Key Laboratory of Composite and Functional Materials, Tianjin University, Tianjin 300072 (China); Jia, Xiaoling [Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, Beijing 100083 (China); Yang, Yang [School of Materials Science and Engineering, Tianjin Key Laboratory of Composite and Functional Materials, Tianjin University, Tianjin 300072 (China); Yang, Qingmao; Gao, Chao [Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, Beijing 100083 (China); Zhao, Yunhui [School of Materials Science and Engineering, Tianjin Key Laboratory of Composite and Functional Materials, Tianjin University, Tianjin 300072 (China); Fan, Yubo, E-mail: yubofan@buaa.edu.cn [Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, Beijing 100083 (China); National Research Center for Rehabilitation Technical Aids, Beijing 100176 (China); Yuan, Xiaoyan, E-mail: yuanxy@tju.edu.cn [School of Materials Science and Engineering, Tianjin Key Laboratory of Composite and Functional Materials, Tianjin University, Tianjin 300072 (China)

    2016-11-01

    The efficiency of biomaterials used in small vascular repair depends greatly on their ability to interact with vascular endothelial cells (VECs). Rapid endothelialization of the vascular grafts is a promising way to prevent thrombosis and intimal hyperplasia. In this work, modification of electrospun membranes of poly(ethylene glycol)-b-poly(L-lactide-co-ε-caprolactone) (PELCL) by three different peptides for regulation of VECs were studied in order to obtain ideal bioactive biomaterials as small diameter vascular grafts. QK (a mimetic peptide to vascular endothelial growth factor), Arg-Glu-Asp-Val (REDV, a specific adhesive peptide to VECs) and Val-Ala-Pro-Gly (VAPG, a specific adhesive peptide to vascular smooth muscle cells) were investigated. Surface properties of the modified membranes and the response of VECs were verified. It was found that protein adsorption and platelet adhesion were effectively suppressed with the introduction of QK, REDV or VAPG peptides on the PELCL electrospun membranes. Both QK- and REDV-modified electrospun membranes could accelerate the proliferation of VECs in the first 9 days, and the QK-modified electrospun membrane promoted cell proliferation more significantly than the REDV-modified one. The REDV-modified PELCL membrane was the most favorable for VECs adhesion than QK- and VAPG-modified membranes. It was suggested that QK- or REDV-modified PELCL electrospun membranes may have great potential applications in cardiovascular biomaterials for rapid endothelialization in situ. - Highlights: • A series of peptide-modified PELCL electrospun membranes were prepared. • Hemocompatibility of the membranes was greatly improved by the modification. • QK-modified PELCL membrane promoted VECs proliferation more significantly. • REDV-modified PELCL membrane was the most favorable for VEC adhesion.

  12. Peptide-modified PELCL electrospun membranes for regulation of vascular endothelial cells

    International Nuclear Information System (INIS)

    Zhou, Fang; Jia, Xiaoling; Yang, Yang; Yang, Qingmao; Gao, Chao; Zhao, Yunhui; Fan, Yubo; Yuan, Xiaoyan

    2016-01-01

    The efficiency of biomaterials used in small vascular repair depends greatly on their ability to interact with vascular endothelial cells (VECs). Rapid endothelialization of the vascular grafts is a promising way to prevent thrombosis and intimal hyperplasia. In this work, modification of electrospun membranes of poly(ethylene glycol)-b-poly(L-lactide-co-ε-caprolactone) (PELCL) by three different peptides for regulation of VECs were studied in order to obtain ideal bioactive biomaterials as small diameter vascular grafts. QK (a mimetic peptide to vascular endothelial growth factor), Arg-Glu-Asp-Val (REDV, a specific adhesive peptide to VECs) and Val-Ala-Pro-Gly (VAPG, a specific adhesive peptide to vascular smooth muscle cells) were investigated. Surface properties of the modified membranes and the response of VECs were verified. It was found that protein adsorption and platelet adhesion were effectively suppressed with the introduction of QK, REDV or VAPG peptides on the PELCL electrospun membranes. Both QK- and REDV-modified electrospun membranes could accelerate the proliferation of VECs in the first 9 days, and the QK-modified electrospun membrane promoted cell proliferation more significantly than the REDV-modified one. The REDV-modified PELCL membrane was the most favorable for VECs adhesion than QK- and VAPG-modified membranes. It was suggested that QK- or REDV-modified PELCL electrospun membranes may have great potential applications in cardiovascular biomaterials for rapid endothelialization in situ. - Highlights: • A series of peptide-modified PELCL electrospun membranes were prepared. • Hemocompatibility of the membranes was greatly improved by the modification. • QK-modified PELCL membrane promoted VECs proliferation more significantly. • REDV-modified PELCL membrane was the most favorable for VEC adhesion.

  13. Facilitated Engraftment of Isolated Islets Coated With Expanded Vascular Endothelial Cells for Islet Transplantation.

    Science.gov (United States)

    Barba-Gutierrez, D Alonso; Daneri-Navarro, A; Villagomez-Mendez, J Jesus Alejandro; Kanamune, J; Robles-Murillo, A Karina; Sanchez-Enriquez, S; Villafan-Bernal, J Rafael; Rivas-Carrillo, J D

    2016-03-01

    Diabetes is complex disease, which involves primary metabolic changes followed by immunological and vascular pathophysiological adjustments. However, it is mostly characterized by an unbalanced decreased number of the β-cells unable to maintain the metabolic requirements and failure to further regenerate newly functional pancreatic islets. The objective of this study was to analyze the properties of the endothelial cells to facilitate the islet cells engraftment after islet transplantation. We devised a co-cultured engineer system to coat isolated islets with vascular endothelial cells. To assess the cell integration of cell-engineered islets, we stained them for endothelial marker CD31 and nuclei counterstained with DAPI dye. We comparatively performed islet transplantations into streptozotocin-induced diabetic mice and recovered the islet grafts for morphometric analyses on days 3, 7, 10, and 30. Blood glucose levels were measured continuously after islet transplantation to monitor the functional engraftment and capacity to achieve metabolic control. Cell-engineered islets showed a well-defined rounded shape after co-culture when compared with native isolated islets. Furthermore, the number of CD31-positive cells layered on the islet surface showed a direct proportion with engraftment capacities and less TUNEL-positive cells on days 3 and 7 after transplantation. We observed that vascular endothelial cells could be functional integrated into isolated islets. We also found that islets that are coated with vascular endothelial cells increased their capacity to engraft. These findings indicate that islets coated with endothelial cells have a greater capacity of engraftment and thus establish a definitely vascular network to support the metabolic requirements. Copyright © 2016 Elsevier Inc. All rights reserved.

  14. Atherogenic ω-6 Lipids Modulate PPAR- EGR-1 Crosstalk in Vascular Cells

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    Jia Fei

    2011-01-01

    Full Text Available Atherogenic ω-6 lipids are physiological ligands of peroxisome proliferator-activated receptors (PPARs and elicit pro- and antiatherogenic responses in vascular cells. The objective of this study was to investigate if ω-6 lipids modulated the early growth response-1 (Egr-1/PPAR crosstalk thereby altering vascular function. Rat aortic smooth muscle cells (RASMCs were exposed to ω-6 lipids, linoleic acid (LA, or its oxidized form, 13-HPODE (OxLA in the presence or absence of a PPARα antagonist (MK886 or PPARγ antagonist (GW9662 or PPAR-specific siRNA. Our results demonstrate that ω-6 lipids, induced Egr-1 and monocyte chemotactic protein-1 (MCP-1 mRNA and protein levels at the acute phase (1–4 hrs when PPARα was downregulated and at subacute phase (4–12 hrs by modulating PPARγ, thus resulting in altered monocyte adhesion to RASMCs. We provide novel insights into the mechanism of action of ω-6 lipids on Egr-1/PPAR interactions in vascular cells and their potential in altering vascular function.

  15. Poly(ADP-ribose polymerase 1 is indispensable for transforming growth factor-β Induced Smad3 activation in vascular smooth muscle cell.

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    Dan Huang

    Full Text Available BACKGROUND: Transforming growth factor type-β (TGF-β/Smad pathway plays an essential role in vascular fibrosis. Reactive oxygen species (ROS generation also mediates TGF-β signaling-induced vascular fibrosis, suggesting that some sort of interaction exists between Smad and redox pathways. However, the underlying molecular mechanism is largely unknown. This study aims to investigate the influence of poly(ADP-ribose polymerase 1 (PARP1, a downstream effector of ROS, on TGF-β signaling transduction through Smad3 pathway in rat vascular smooth muscle cells (VSMCs. METHODS AND RESULTS: TGF-β1 treatment promoted PARP1 activation through induction of ROS generation in rat VSMCs. TGF-β1-induced phosphorylation and nuclear accumulation of Smad3 was prevented by treatment of cells with PARP inhibitor, 3-aminobenzamide (3AB or N-(6-oxo-5,6-dihydrophenanthridin-2-yl-2-(N,N-dimethylaminoacetami (PJ34, or PARP1 siRNA. TGF-β1 treatment promoted poly(ADP-ribosylation of Smad3 via activation of PARP1 in the nucleus. Poly(ADP-ribosylation enhanced Smad-Smad binding element (SBE complex formation in nuclear extracts and increased DNA binding activity of Smad3. Pretreatment with 3AB, PJ34, or PARP1 siRNA prevented TGF-β1-induced Smad3 transactivation and expression of Smad3 target genes, including collagen Iα1, collagen IIIα1 and tissue inhibitor of metalloproteinase 1, in rat VSMCs. CONCLUSIONS: PARP1 is indispensable for TGF-β1 induced Smad3 activation in rat VSMCs. Targeting PARP1 may be a promising therapeutic approach against vascular diseases induced by dysregulation of TGF-β/Smad3 pathway.

  16. The effect of ionizing radiation on the filamentous actin of vascular endothelial cell

    International Nuclear Information System (INIS)

    Yao Xiaowu; Chen Shisheng; Yang Lihe; Lin Juelong; Yang Haiwei

    2006-01-01

    Objective: To observe the ionizing radiation effect on filamentous actin of vascular endothelial cell and explore its mechanism. Methods: The vascular endothelial cells were irradiated with 0, 2, 4, 6, 8, 10 and 12 Gy 60 Co γ-rays. The cytoskeleton was observed with CLSM at 6 hs after the irradiation and the cytoskeleton protein F-actin detected with flow cytometry after 12 and 24 hs. Results: The damage to cytoskeletons increased with the radiation dose. The cytoskeleton protein F-actin was significantly decreased at 12 hs after the irradiation, and then recovered after 24 hs. Conclusion: Ionizing radiation caused vascular endothelial cell injury by damaging the cytoskeleton and depolymerizating the F-actin. (authors)

  17. Vascular endothelial growth factor modified macrophages transdifferentiate into endothelial-like cells and decrease foam cell formation.

    Science.gov (United States)

    Yan, Dan; He, Yujuan; Dai, Jun; Yang, Lili; Wang, Xiaoyan; Ruan, Qiurong

    2017-06-30

    Macrophages are largely involved in the whole process of atherosclerosis from an initiation lesion to an advanced lesion. Endothelial disruption is the initial step and macrophage-derived foam cells are the hallmark of atherosclerosis. Promotion of vascular integrity and inhibition of foam cell formation are two important strategies for preventing atherosclerosis. How can we inhibit even the reverse negative role of macrophages in atherosclerosis? The present study was performed to investigate if overexpressing endogenous human vascular endothelial growth factor (VEGF) could facilitate transdifferentiation of macrophages into endothelial-like cells (ELCs) and inhibit foam cell formation. We demonstrated that VEGF-modified macrophages which stably overexpressed human VEGF (hVEGF 165 ) displayed a high capability to alter their phenotype and function into ELCs in vitro Exogenous VEGF could not replace endogenous VEGF to induce the transdifferentiation of macrophages into ELCs in vitro We further showed that VEGF-modified macrophages significantly decreased cytoplasmic lipid accumulation after treatment with oxidized LDL (ox-LDL). Moreover, down-regulation of CD36 expression in these cells was probably one of the mechanisms of reduction in foam cell formation. Our results provided the in vitro proof of VEGF-modified macrophages as atheroprotective therapeutic cells by both promotion of vascular repair and inhibition of foam cell formation. © 2017 The Author(s).

  18. Functional vascular smooth muscle cells derived from human induced pluripotent stem cells via mesenchymal stem cell intermediates

    Science.gov (United States)

    Bajpai, Vivek K.; Mistriotis, Panagiotis; Loh, Yuin-Han; Daley, George Q.; Andreadis, Stelios T.

    2012-01-01

    Aims Smooth muscle cells (SMC) play an important role in vascular homeostasis and disease. Although adult mesenchymal stem cells (MSC) have been used as a source of contractile SMC, they suffer from limited proliferation potential and culture senescence, particularly when originating from older donors. By comparison, human induced pluripotent stem cells (hiPSC) can provide an unlimited source of functional SMC for autologous cell-based therapies and for creating models of vascular disease. Our goal was to develop an efficient strategy to derive functional, contractile SMC from hiPSC. Methods and results We developed a robust, stage-wise, feeder-free strategy for hiPSC differentiation into functional SMC through an intermediate stage of multipotent MSC, which could be coaxed to differentiate into fat, bone, cartilage, and muscle. At this stage, the cells were highly proliferative and displayed higher clonogenic potential and reduced senescence when compared with parental hair follicle mesenchymal stem cells. In addition, when exposed to differentiation medium, the myogenic proteins such as α-smooth muscle actin, calponin, and myosin heavy chain were significantly upregulated and displayed robust fibrillar organization, suggesting the development of a contractile phenotype. Indeed, tissue constructs prepared from these cells exhibited high levels of contractility in response to receptor- and non-receptor-mediated agonists. Conclusion We developed an efficient stage-wise strategy that enabled hiPSC differentiation into contractile SMC through an intermediate population of clonogenic and multipotent MSC. The high yield of MSC and SMC derivation suggests that our strategy may facilitate an acquisition of the large numbers of cells required for regenerative medicine or for studying vascular disease pathophysiology. PMID:22941255

  19. Hydroxysafflor yellow A suppresses oxidized low density lipoprotein induced proliferation of vascular smooth muscle cells

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    Lin Sheng

    2012-06-01

    Full Text Available To investigate the relationship between the suppression of Hydroxysafflor yellow A (HSYA on the oxidized low density lipoprotein (ox-LDL induced proliferation of vascular smooth muscle cells (VSMCs and the mRNA and protein expression of extracellular signal-regulated protein kinase 1/2 (ERK1/2 and mitogen activated protein kinase phospholipase-1 (MAKP-1, VSMCs were treated with HSYA at 10 ?mol/L and/or ox-LDL at 35 mg/L for 48 h. MTT assay was done to measure cell survival rate, flow cytometry to detect cell cycle, reverse transcription PCR and Western blot to detect the expression of ERK1/2 and MAKP-1. When compared to cells treated with ox-LDL alone, the survival rate of cells treated with two reagents was reduced and the proportion of cells in G0/G1 phase significantly increased, with increased MKP-1 expression. The study suggests HSYA can inhibit VSMC proliferation via increasing MKP-1 expression, reducing p-ERK1/2 activity and suppressing cell cycle.

  20. Incorporation of bone marrow cells in pancreatic pseudoislets improves posttransplant vascularization and endocrine function.

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    Christine Wittig

    Full Text Available Failure of revascularization is known to be the major reason for the poor outcome of pancreatic islet transplantation. In this study, we analyzed whether pseudoislets composed of islet cells and bone marrow cells can improve vascularization and function of islet transplants. Pancreatic islets isolated from Syrian golden hamsters were dispersed into single cells for the generation of pseudoislets containing 4×10(3 cells. To create bone marrow cell-enriched pseudoislets 2×10(3 islet cells were co-cultured with 2×10(3 bone marrow cells. Pseudoislets and bone marrow cell-enriched pseudoislets were transplanted syngeneically into skinfold chambers to study graft vascularization by intravital fluorescence microscopy. Native islet transplants served as controls. Bone marrow cell-enriched pseudoislets showed a significantly improved vascularization compared to native islets and pseudoislets. Moreover, bone marrow cell-enriched pseudoislets but not pseudoislets normalized blood glucose levels after transplantation of 1000 islet equivalents under the kidney capsule of streptozotocin-induced diabetic animals, although the bone marrow cell-enriched pseudoislets contained only 50% of islet cells compared to pseudoislets and native islets. Fluorescence microscopy of bone marrow cell-enriched pseudoislets composed of bone marrow cells from GFP-expressing mice showed a distinct fraction of cells expressing both GFP and insulin, indicating a differentiation of bone marrow-derived cells to an insulin-producing cell-type. Thus, enrichment of pseudoislets by bone marrow cells enhances vascularization after transplantation and increases the amount of insulin-producing tissue. Accordingly, bone marrow cell-enriched pseudoislets may represent a novel approach to increase the success rate of islet transplantation.

  1. In vitro proliferative capacity of vascular cells irradiated in vivo

    International Nuclear Information System (INIS)

    Fischer-Dzoga, K.; Dimitrievich, G.S.; Griem, M.L.

    1985-01-01

    Explants were prepared from rabbit vascular aortic layers and irradiated with x-ray doses ranging from 100 cGy-5 cGy. This resulted in a 50% reduction in number of outgrowing cells with doses of 100-125 gy. Doses of 250, 500 and 750 gy resulted in a reduction of 70, 90, and 95% respectively. However, when the rabbit was irradiated in vivo to a narrow mediastinal port immediately before the explantation of vascular tissue, the number of outgrowing cells was comparable to that of the irradiated control for doses up to 250 cGy, while doses of 500 and 750 cGy reduced outgrowth by 60 and 93% respectively. To test for in situ repair, the time interval between irradiation and explantation was prolonged from 1-4 hours in one hour increments. The results were scored as average number of cells/explant and average number of cells/growing culture

  2. Bioreactor-induced mesenchymal progenitor cell differentiation and elastic fiber assembly in engineered vascular tissues.

    Science.gov (United States)

    Lin, Shigang; Mequanint, Kibret

    2017-09-01

    In vitro maturation of engineered vascular tissues (EVT) requires the appropriate incorporation of smooth muscle cells (SMC) and extracellular matrix (ECM) components similar to native arteries. To this end, the aim of the current study was to fabricate 4mm inner diameter vascular tissues using mesenchymal progenitor cells seeded into tubular scaffolds. A dual-pump bioreactor operating either in perfusion or pulsatile perfusion mode was used to generate physiological-like stimuli to promote progenitor cell differentiation, extracellular elastin production, and tissue maturation. Our data demonstrated that pulsatile forces and perfusion of 3D tubular constructs from both the lumenal and ablumenal sides with culture media significantly improved tissue assembly, effectively inducing mesenchymal progenitor cell differentiation to SMCs with contemporaneous elastin production. With bioreactor cultivation, progenitor cells differentiated toward smooth muscle lineage characterized by the expression of smooth muscle (SM)-specific markers smooth muscle alpha actin (SM-α-actin) and smooth muscle myosin heavy chain (SM-MHC). More importantly, pulsatile perfusion bioreactor cultivation enhanced the synthesis of tropoelastin and its extracellular cross-linking into elastic fiber compared with static culture controls. Taken together, the current study demonstrated progenitor cell differentiation and vascular tissue assembly, and provides insights into elastin synthesis and assembly to fibers. Incorporation of elastin into engineered vascular tissues represents a critical design goal for both mechanical and biological functions. In the present study, we seeded porous tubular scaffolds with multipotent mesenchymal progenitor cells and cultured in dual-pump pulsatile perfusion bioreactor. Physiological-like stimuli generated by bioreactor not only induced mesenchymal progenitor cell differentiation to vascular smooth muscle lineage but also actively promoted elastin synthesis and

  3. The angiotensin-(1-7/Mas axis counteracts angiotensin II-dependent and –independent pro-inflammatory signaling in human vascular smooth muscle cells

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    Laura A Villalobos

    2016-12-01

    Full Text Available Background and aims: Targeting inflammation is nowadays considered as a challenging pharmacological strategy to prevent or delay the development of vascular diseases. Angiotensin-(1-7 is a member of the renin-angiotensin system (RAS that binds Mas receptors and has gained growing attention in the last years as a regulator of vascular homeostasis. Here, we explored the capacity of Ang-(1-7 to counteract human aortic smooth muscle cell (HASMC inflammation triggered by RAS-dependent and –independent stimuli, such as Ang II or interleukin (IL-1.Methods and Results: In cultured HASMC, the expression of iNOS and the release of nitric oxide were stimulated by both Ang II and IL-1, as determined by Western blot and indirect immunofluorescence or the Griess method, respectively. iNOS induction was inhibited by Ang-(1-7 in a concentration-dependent manner. This effect was equally blocked by two different Mas receptor antagonists, A779 and D-Pro7-Ang-(1-7, suggesting the participation of a unique Mas receptor subtype. Using pharmacological inhibitors, the induction of iNOS was proven to rely on the consecutive upstream activation of NADPH oxidase and NF-B. Indeed, Ang-(1-7 markedly inhibited the activation of the NADPH oxidase and subsequently of NF-B, as determined by lucigenin-derived chemiluminiscence and electromobility shift assay, respectively.Conclusion: Ang-(1-7 can act as a counter-regulator of the inflammation of vascular smooth muscle cells triggered by Ang II, but also by other stimuli beyond the RAS. Activating or mimicking the Ang-(1-7/Mas axis may represent a pharmacological opportunity to attenuate the pro-inflammatory environment that promotes and sustains the development of vascular diseases.

  4. Initiation and Propagation of Vascular Calcification Is Regulated by a Concert of Platelet- and Smooth Muscle Cell-Derived Extracellular Vesicles

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    Leon J. Schurgers

    2018-04-01

    Full Text Available The ageing population continues to suffer from its primary killer, cardiovascular disease (CVD. Despite recent advances in interventional medicinal and surgical therapies towards the end of the 20th century, the epidemic of cardiovascular disease has not been halted. Yet, rather than receding globally, the burden of CVD has risen to become a top cause of morbidity and mortality worldwide. Most CVD arises from thrombotic rupture of an atherosclerotic plaque, the pathologic thickening of coronary and carotid artery segments and subsequent distal ischemia in heart or brain. In fact, one-fifth of deaths are directly attributable to thrombotic rupture of a vulnerable plaque. Atherosclerotic lesion formation is caused by a concert of interactions between circulating leukocytes and platelets, interacting with the endothelial barrier, signalling into the arterial wall by the release of cytokines and extracellular vesicles (EVs. Both platelet- and cell-derived EVs represent a novel mechanism of cellular communication, particularly by the transport and transfer of cargo and by reprogramming of the recipient cell. These interactions result in phenotypic switching of vascular smooth muscle cells (VSMCs causing migration and proliferation, and subsequent secretion of EVs. Loss of VSMCs attracts perivascular Mesenchymal Stem Cells (MSCs from the adventitia, which are a source of VSMCs and contribute to repair after vascular injury. However, continuous stress stimuli eventually switch phenotype of cells into osteochondrogenic VSMCs facilitating vascular calcification. Although Virchow’s triad is over 100 years old, it is a reality that is accurate today. It can be briefly summarised as changes in the composition of blood (platelet EVs, alterations in the vessel wall (VSMC phenotypic switching, MSC infiltration and EV release and disruption of blood flow (atherothrombosis. In this paper, we review the latest relevant advances in the identification of

  5. Glycolipids from spinach suppress LPS-induced vascular inflammation through eNOS and NK-κB signaling.

    Science.gov (United States)

    Ishii, Masakazu; Nakahara, Tatsuo; Araho, Daisuke; Murakami, Juri; Nishimura, Masahiro

    2017-07-01

    Glycolipids are the major constituent of the thylakoid membrane of higher plants and have a variety of biological and pharmacological activities. However, anti-inflammatory effects of glycolipids on vascular endothelial cells have not been elucidated. Here, we investigated the effect of glycolipids extracted from spinach on lipopolysaccharides (LPS)-induced endothelial inflammation and evaluated the underlying molecular mechanisms. Treatment with glycolipids from spinach had no cytotoxic effects on cultured human umbilical vein endothelial cells (HUVECs) and significantly blocked the expression of LPS-induced interleukin (IL)-6, monocyte chemoattractant protein-1 (MCP-1), vascular cell adhesion molecule-1 (VCAM-1), and intracellular adhesion molecule-1 (ICAM-1) in them. Glycolipids treatment also effectively suppressed monocyte adhesion to HUVECs. Treatment with glycolipids inhibited LPS-induced NF-κB phosphorylation and nuclear translocation. In addition, glycolipids treatment significantly promoted endothelial nitric oxide synthase (eNOS) activation and nitric oxide (NO) production in HUVECs. Furthermore, glycolipids treatment blocked LPS-induced inducible NOS (iNOS) expression in HUVECs. Pretreatment with a NOS inhibitor attenuated glycolipids-induced suppression of NF-κB activation and adhesion molecule expression, and abolished the glycolipids-mediated suppression of monocyte adhesion to HUVECs. These results indicate that glycolipids suppress LPS-induced vascular inflammation through attenuation of the NF-κB pathway by increasing NO production in endothelial cells. These findings suggest that glycolipids from spinach may have a potential therapeutic use for inflammatory vascular diseases. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  6. Mast cell chymase induces smooth muscle cell apoptosis by disrupting NF-κB-mediated survival signaling

    International Nuclear Information System (INIS)

    Leskinen, Markus J.; Heikkilae, Hanna M.; Speer, Mei Y.; Hakala, Jukka K.; Laine, Mika; Kovanen, Petri T.; Lindstedt, Ken A.

    2006-01-01

    Chymase released from activated mast cells induces apoptosis of vascular smooth muscle cells (SMCs) in vitro by degrading the pericellular matrix component fibronectin, so causing disruption of focal adhesion complexes and Akt dephosphorylation, which are necessary for cell adhesion and survival. However, the molecular mechanisms of chymase-mediated apoptosis downstream of Akt have remained elusive. Here, we show by means of RT-PCR, Western blotting, EMSA, immunocytochemistry and confocal microscopy, that chymase induces SMC apoptosis by disrupting NF-κB-mediated survival signaling. Following chymase treatment, the translocation of active NF-κB/p65 to the nucleus was partly abolished and the amount of nuclear p65 was reduced. Pretreatment of SMCs with chymase also inhibited LPS- and IL-1β-induced nuclear translocation of p65. The chymase-induced degradation of p65 was mediated by active caspases. Loss of NF-κB-mediated transactivation resulted in downregulation of bcl-2 mRNA and protein expression, leading to mitochondrial swelling and release of cytochrome c. The apoptotic process involved activation of both caspase 9 and caspase 8. The results reveal that, by disrupting the NF-κB-mediated survival-signaling pathway, activated chymase-secreting mast cells can mediate apoptosis of cultured arterial SMCs. Since activated mast cells colocalize with apoptotic SMCs in vulnerable areas of human atherosclerotic plaques, they may participate in the weakening and rupture of atherosclerotic plaques

  7. ROBO4-Mediated Vascular Integrity Regulates the Directionality of Hematopoietic Stem Cell Trafficking

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    Stephanie Smith-Berdan

    2015-02-01

    Full Text Available Despite the use of hematopoietic stem cells (HSCs in clinical therapy for over half a century, the mechanisms that regulate HSC trafficking, engraftment, and life-long persistence after transplantation are unclear. Here, we show that the vascular endothelium regulates HSC trafficking into and out of bone marrow (BM niches. Surprisingly, we found that instead of acting as barriers to cellular entry, vascular endothelial cells, via the guidance molecule ROBO4, actively promote HSC translocation across vessel walls into the BM space. In contrast, we found that the vasculature inhibits the reverse process, as induced vascular permeability led to a rapid increase in HSCs in the blood stream. Thus, the vascular endothelium reinforces HSC localization to BM niches both by promoting HSC extravasation from blood-to-BM and by forming vascular barriers that prevent BM-to-blood escape. Our results uncouple the mechanisms that regulate the directionality of HSC trafficking and show that the vasculature can be targeted to improve hematopoietic transplantation therapies.

  8. Autoantigens targeted in scleroderma patients with vascular disease are enriched in endothelial lineage cells

    Science.gov (United States)

    McMahan, Zsuzsanna H.; Cottrell, Tricia R.; Wigley, Fredrick M.; Antiochos, Brendan; Zambidis, Elias T.; Park, Tea Soon; Halushka, Marc K.; Gutierrez-Alamillo, Laura; Cimbro, Raffaello; Rosen, Antony; Casciola-Rosen, Livia

    2016-01-01

    Objective Scleroderma patients with autoantibodies to centromere proteins (CENPs) and/or interferon-inducible protein 16 (IFI16) are at increased risk of severe vascular complications. We set out to define whether these autoantigens are enriched in cells of the vasculature. Methods Successive stages of embryoid bodies (EBs) as well as vascular progenitors were used to evaluate the expression of scleroderma autoantigens IFI16 and CENP by immunoblotting. CD31 was included to mark early blood vessels. IFI16 and CD31 expression were defined in skin paraffin sections from scleroderma patients and from healthy controls. IFI16 expression was determined by flow cytometry in circulating endothelial cells (CECs) and circulating progenitor cells (CPCs). Results Expression of CENP-A, IFI16 and CD31 was enriched in EBs at days 10 and 12 of differentiation, and particularly in cultures enriched in vascular progenitors (IFI16, CD31, CENPs A and-B). This pattern was distinct from that of comparator autoantigens. Immunohistochemical staining of skin paraffin sections showed enrichment of IFI16 in CD31-positive vascular endothelial cells in biopsies from scleroderma patients and normal controls. Flow cytometry analysis revealed IFI16 expression in CPCs, but minimal expression in CECs. Conclusion Expression of scleroderma autoantigens IFI16 and CENPs, which are associated with severe vascular disease, is increased in vascular progenitors and mature endothelial cells. High level, lineage-enriched expression of autoantigens may explain the striking association between clinical phenotypes and the immune targeting of specific autoantigens. PMID:27159521

  9. Fibroblast growth factor-2 induces osteogenic differentiation through a Runx2 activation in vascular smooth muscle cells

    Energy Technology Data Exchange (ETDEWEB)

    Nakahara, Takehiro; Sato, Hiroko; Shimizu, Takehisa; Tanaka, Toru; Matsui, Hiroki; Kawai-Kowase, Keiko; Sato, Mahito; Iso, Tatsuya; Arai, Masashi [Department of Medicine and Biological Science, Gunma University Graduate School of Medicine, 3-39-15 Showa-machi, Maebashi, Gunma 371-8511 (Japan); Kurabayashi, Masahiko, E-mail: mkuraba@med.gunma-u.ac.jp [Department of Medicine and Biological Science, Gunma University Graduate School of Medicine, 3-39-15 Showa-machi, Maebashi, Gunma 371-8511 (Japan)

    2010-04-02

    Expression of bone-associated proteins and osteoblastic transcription factor Runx2 in arterial cells has been implicated in the development of vascular calcification. However, the signaling upstream of the Runx2-mediated activation of osteoblastic program in vascular smooth muscle cells (VSMC) is poorly understood. We examined the effects of fibroblast growth factor-2 (FGF-2), an important regulator of bone formation, on osteoblastic differentiation of VSMC. Stimulation of cultured rat aortic SMC (RASMC) with FGF-2 induced the expression of the osteoblastic markers osteopontin (OPN) and osteocalcin. Luciferase assays showed that FGF-2 induced osteocyte-specific element (OSE)-dependent transcription. Downregulation of Runx2 by siRNA repressed the basal and FGF-2-stimulated expression of the OPN gene in RASMC. FGF-2 produced hydrogen peroxide in RASMC, as evaluated by fluorescent probe. Induction of OPN expression by FGF-2 was inhibited not only by PD98059 (MEK1 inhibitor) and PP1 (c-Src inhibitor), but also by an antioxidant, N-acetyl cysteine. Nuclear extracts from FGF-2-treated RASMC exhibited increased DNA-binding of Runx2 to its target sequence. Immunohistochemistry of human coronary atherectomy specimens and calcified aortic tissues showed that expression of FGF receptor-1 and Runx2 was colocalized. In conclusion, these results suggest that FGF-2 plays a role in inducing osteoblastic differentiation of VSMC by activating Runx2 through mitogen-activated protein kinase (MAPK)-dependent- and oxidative stress-sensitive-signaling pathways.

  10. Cholesterol is necessary both for the toxic effect of Abeta peptides on vascular smooth muscle cells and for Abeta binding to vascular smooth muscle cell membranes.

    Science.gov (United States)

    Subasinghe, Supundi; Unabia, Sharon; Barrow, Colin J; Mok, Su San; Aguilar, Marie-Isabel; Small, David H

    2003-02-01

    Accumulation of beta amyloid (Abeta) in the brain is central to the pathogenesis of Alzheimer's disease. Abeta can bind to membrane lipids and this binding may have detrimental effects on cell function. In this study, surface plasmon resonance technology was used to study Abeta binding to membranes. Abeta peptides bound to synthetic lipid mixtures and to an intact plasma membrane preparation isolated from vascular smooth muscle cells. Abeta peptides were also toxic to vascular smooth muscle cells. There was a good correlation between the toxic effect of Abeta peptides and their membrane binding. 'Ageing' the Abeta peptides by incubation for 5 days increased the proportion of oligomeric species, and also increased toxicity and the amount of binding to lipids. The toxicities of various Abeta analogs correlated with their lipid binding. Significantly, binding was influenced by the concentration of cholesterol in the lipid mixture. Reduction of cholesterol in vascular smooth muscle cells not only reduced the binding of Abeta to purified plasma membrane preparations but also reduced Abeta toxicity. The results support the view that Abeta toxicity is a direct consequence of binding to lipids in the membrane. Reduction of membrane cholesterol using cholesterol-lowering drugs may be of therapeutic benefit because it reduces Abeta-membrane binding.

  11. Sodium valproate, a histone deacetylase inhibitor, modulates the vascular endothelial growth inhibitor-mediated cell death in human osteosarcoma and vascular endothelial cells.

    Science.gov (United States)

    Yamanegi, Koji; Kawabe, Mutsuki; Futani, Hiroyuki; Nishiura, Hiroshi; Yamada, Naoko; Kato-Kogoe, Nahoko; Kishimoto, Hiromitsu; Yoshiya, Shinichi; Nakasho, Keiji

    2015-05-01

    The level of vascular endothelial growth inhibitor (VEGI) has been reported to be negatively associated with neovascularization in malignant tumors. The soluble form of VEGI is a potent anti-angiogenic factor due to its effects in inhibiting endothelial cell proliferation. This inhibition is mediated by death receptor 3 (DR3), which contains a death domain in its cytoplasmic tail capable of inducing apoptosis that can be subsequently blocked by decoy receptor 3 (DcR3). We investigated the effects of sodium valproate (VPA) and trichostatin A (TSA), histone deacetylase inhibitors, on the expression of VEGI and its related receptors in human osteosarcoma (OS) cell lines and human microvascular endothelial (HMVE) cells. Consequently, treatment with VPA and TSA increased the VEGI and DR3 expression levels without inducing DcR3 production in the OS cell lines. In contrast, the effect on the HMVE cells was limited, with no evidence of growth inhibition or an increase in the DR3 and DcR3 expression. However, VPA-induced soluble VEGI in the OS cell culture medium markedly inhibited the vascular tube formation of HMVE cells, while VEGI overexpression resulted in enhanced OS cell death. Taken together, the HDAC inhibitor has anti-angiogenesis and antitumor activities that mediate soluble VEGI/DR3-induced apoptosis via both autocrine and paracrine pathways. This study indicates that the HDAC inhibitor may be exploited as a therapeutic strategy modulating the soluble VEGI/DR3 pathway in osteosarcoma patients.

  12. Effects of anti-vascular endothelial growth factor monoclonal antibody (bevacizumab on lens epithelial cells

    Directory of Open Access Journals (Sweden)

    Jun JH

    2016-06-01

    Full Text Available Jong Hwa Jun,1 Wern-Joo Sohn,2 Youngkyun Lee,2 Jae-Young Kim21Department of Ophthalmology, School of Medicine, Dongsan Medical Center, Keimyung University, 2Department of Oral Biochemistry, School of Dentistry, IHBR, Kyungpook National University, Daegu, South KoreaAbstract: The molecular and cellular effects of anti-vascular endothelial growth factor monoclonal antibody (bevacizumab on lens epithelial cells (LECs were examined using both an immortalized human lens epithelial cell line and a porcine capsular bag model. After treatment with various concentrations of bevacizumab, cell viability and proliferation patterns were evaluated using the water-soluble tetrazolium salt assay and 5-bromo-2'-deoxyuridine enzyme-linked immunosorbent assay, respectively. The scratch assay and Western blot analysis were employed to validate the cell migration pattern and altered expression levels of signaling molecules related to the epithelial–mesenchymal transition (EMT. Application of bevacizumab induced a range of altered cellular events in a concentration-dependent manner. A 0.1–2 mg/mL concentration demonstrated dose-dependent increase in proliferation and viability of LECs. However, 4 mg/mL decreased cell proliferation and viability. Cell migrations displayed dose-dependent retardation from 0.1 mg/mL bevacizumab treatment. Transforming growth factor-β2 expression was markedly increased in a dose-dependent manner, and α-smooth muscle actin, matrix metalloproteinase-9, and vimentin expression levels showed dose-dependent changes in a B3 cell line. Microscopic observation of porcine capsular bag revealed changes in cellular morphology and a decline in cell density compared to the control after 2 mg/mL treatment. The central aspect of posterior capsule showed delayed confluence, and the factors related to EMT revealed similar expression patterns to those identified in the cell line. Based on these results, bevacizumab modulates the proliferation

  13. Estrogen, vascular estrogen receptor and hormone therapy in postmenopausal vascular disease.

    Science.gov (United States)

    Khalil, Raouf A

    2013-12-15

    Cardiovascular disease (CVD) is less common in premenopausal women than men of the same age or postmenopausal women, suggesting vascular benefits of estrogen. Estrogen activates estrogen receptors ERα, ERβ and GPR30 in endothelium and vascular smooth muscle (VSM), which trigger downstream signaling pathways and lead to genomic and non-genomic vascular effects such as vasodilation, decreased VSM contraction and growth and reduced vascular remodeling. However, randomized clinical trials (RCTs), such as the Women's Health Initiative (WHI) and Heart and Estrogen/progestin Replacement Study (HERS), have shown little vascular benefits and even adverse events with menopausal hormone therapy (MHT), likely due to factors related to the MHT used, ER profile, and RCT design. Some MHT forms, dose, combinations or route of administration may have inadequate vascular effects. Age-related changes in ER amount, distribution, integrity and post-ER signaling could alter the vascular response to MHT. The subject's age, preexisting CVD, and hormone environment could also reduce the effects of MHT. Further evaluation of natural and synthetic estrogens, phytoestrogens, and selective estrogen-receptor modulators (SERMs), and the design of appropriate MHT combinations, dose, route and 'timing' could improve the effectiveness of conventional MHT and provide alternative therapies in the peri-menopausal period. Targeting ER using specific ER agonists, localized MHT delivery, and activation of specific post-ER signaling pathways could counter age-related changes in ER. Examination of the hormone environment and conditions associated with hormone imbalance such as polycystic ovary syndrome may reveal the causes of abnormal hormone-receptor interactions. Consideration of these factors in new RCTs such as the Kronos Early Estrogen Prevention Study (KEEPS) could enhance the vascular benefits of estrogen in postmenopausal CVD. Copyright © 2013 Elsevier Inc. All rights reserved.

  14. Angiogenesis mediated by soluble forms of E-selectin and vascular cell adhesion molecule-1

    Science.gov (United States)

    Koch, Alisa E.; Halloran, Margaret M.; Haskell, Catherine J.; Shah, Manisha R.; Polverini, Peter J.

    1995-08-01

    ENDOTHELIAL adhesion molecules facilitate the entry of leukocytes into inflamed tissues. This in turn promotes neovascularization, a process central to the progression of rheumatoid arthritis, tumour growth and wound repair1. Here we test the hypothesis that soluble endothelial adhesion molecules promote angiogenesis2á¤-4. Human recombinant soluble E-selectin and soluble vascular cell adhesion molecule-1 induced chemotaxis of human endothelial cells in vitro and were angiogenic in rat cornea. Soluble E-selectin acted on endothelial cells in part through a sialyl Lewis-X-dependent mechanism, while soluble vascular cell adhesion molecule-1 acted on endothelial cells in part through a very late antigen (VLA)-4 dependent mechanism. The chemotactic activity of rheumatoid synovial fluid for endothelial cells, and also its angiogenic activity, were blocked by antibodies to either soluble E-selectin or soluble vascular cell adhesion molecule-1. These results suggest a novel function for soluble endothelial adhesion molecules as mediators of angiogenesis.

  15. Vascular pattern of the dentate gyrus is regulated by neural progenitors.

    Science.gov (United States)

    Pombero, Ana; Garcia-Lopez, Raquel; Estirado, Alicia; Martinez, Salvador

    2018-05-01

    Neurogenesis is a vital process that begins during early embryonic development and continues until adulthood, though in the latter case, it is restricted to the subventricular zone and the subgranular zone of the dentate gyrus (DG). In particular, the DG's neurogenic properties are structurally and functionally unique, which may be related to its singular vascular pattern. Neurogenesis and angiogenesis share molecular signals and act synergistically, supporting the concept of a neurogenic niche as a functional unit between neural precursors cells and their environment, in which the blood vessels play an important role. Whereas it is well known that vascular development controls neural proliferation in the embryonary and in the adult brain, by releasing neurotrophic factors; the potential influence of neural cells on vascular components during angiogenesis is largely unknown. We have demonstrated that the reduction of neural progenitors leads to a significant impairment of vascular development. Since VEGF is a potential regulator in the neurogenesis-angiogenesis crosstalk, we were interested in assessing the possible role of this molecule in the hippocampal neurovascular development. Our results showed that VEGF is the molecule involved in the regulation of vascular development by neural progenitor cells in the DG.

  16. Biophysical induction of vascular smooth muscle cell podosomes.

    Directory of Open Access Journals (Sweden)

    Na Young Kim

    Full Text Available Vascular smooth muscle cell (VSMC migration and matrix degradation occurs with intimal hyperplasia associated with atherosclerosis, vascular injury, and restenosis. One proposed mechanism by which VSMCs degrade matrix is through the use of podosomes, transient actin-based structures that are thought to play a role in extracellular matrix degradation by creating localized sites of matrix metalloproteinase (MMP secretion. To date, podosomes in VSMCs have largely been studied by stimulating cells with phorbol esters, such as phorbol 12,13-dibutyrate (PDBu, however little is known about the physiological cues that drive podosome formation. We present the first evidence that physiological, physical stimuli mimicking cues present within the microenvironment of diseased arteries can induce podosome formation in VSMCs. Both microtopographical cues and imposed pressure mimicking stage II hypertension induce podosome formation in A7R5 rat aortic smooth muscle cells. Moreover, wounding using a scratch assay induces podosomes at the leading edge of VSMCs. Notably the effect of each of these biophysical stimuli on podosome stimulation can be inhibited using a Src inhibitor. Together, these data indicate that physical cues can induce podosome formation in VSMCs.

  17. Non-invasive stem cell therapy in a rat model for retinal degeneration and vascular pathology.

    Directory of Open Access Journals (Sweden)

    Shaomei Wang

    Full Text Available BACKGROUND: Retinitis pigmentosa (RP is characterized by progressive night blindness, visual field loss, altered vascular permeability and loss of central vision. Currently there is no effective treatment available except gene replacement therapy has shown promise in a few patients with specific gene defects. There is an urgent need to develop therapies that offer generic neuro-and vascular-protective effects with non-invasive intervention. Here we explored the potential of systemic administration of pluripotent bone marrow-derived mesenchymal stem cells (MSCs to rescue vision and associated vascular pathology in the Royal College Surgeons (RCS rat, a well-established animal model for RP. METHODOLOGY/PRINCIPAL FINDINGS: Animals received syngeneic MSCs (1x10(6 cells by tail vein at an age before major photoreceptor loss. PRINCIPAL RESULTS: both rod and cone photoreceptors were preserved (5-6 cells thick at the time when control animal has a single layer of photoreceptors remained; Visual function was significantly preserved compared with controls as determined by visual acuity and luminance threshold recording from the superior colliculus; The number of pathological vascular complexes (abnormal vessels associated with migrating pigment epithelium cells and area of vascular leakage that would ordinarily develop were dramatically reduced; Semi-quantitative RT-PCR analysis indicated there was upregulation of growth factors and immunohistochemistry revealed that there was an increase in neurotrophic factors within eyes of animals that received MSCs. CONCLUSIONS/SIGNIFICANCE: These results underscore the potential application of MSCs in treating retinal degeneration. The advantages of this non-invasive cell-based therapy are: cells are easily isolated and can be expanded in large quantity for autologous graft; hypoimmunogenic nature as allogeneic donors; less controversial in nature than other stem cells; can be readministered with minor discomfort

  18. Liver cell-derived microparticles activate hedgehog signaling and alter gene expression in hepatic endothelial cells.

    Science.gov (United States)

    Witek, Rafal P; Yang, Liu; Liu, Renshui; Jung, Youngmi; Omenetti, Alessia; Syn, Wing-Kin; Choi, Steve S; Cheong, Yeiwon; Fearing, Caitlin M; Agboola, Kolade M; Chen, Wei; Diehl, Anna Mae

    2009-01-01

    Angiogenesis contributes to vascular remodeling during cirrhosis. In cirrhotic livers, cholangiocytes, and myofibroblastic hepatic stellate cells (MF-HSC) produce Hedgehog (Hh) ligands. During embryogenesis Hh ligands are released from ligand-producing cells in microparticles and activate Hh signaling in endothelial cells. We studied whether adult liver cell-derived microparticles contain Hh ligands that alter hepatic sinusoidal endothelial cells (SEC). MF-HSC and cholangiocytes were exposed to platelet-derived growth factor to induce Hh ligands; microparticles were isolated from medium, analyzed by transmission electron microscopy and immunoblots, and applied to Hh-reporter-containing cells. Microparticles were obtained from serum and bile of rats after bile duct ligation (BDL) or sham surgery and applied to normal primary liver SEC with or without cyclopamine, an Hh signaling inhibitor. Effects on SEC gene expression were evaluated by quantitative reverse-transcription polymerase chain reaction and immunoblotting. Hh target gene expression and SEC activation markers were compared in primary SEC and in liver sections from healthy and BDL rats. Platelet-derived growth factor-treated MF-HSC and cholangiocytes released exosome-enriched microparticles containing biologically-active Hh ligands. BDL increased release of Hh-containing exosome-enriched microparticles into plasma and bile. Transmission electron microscopy and immunoblots revealed similarities among microparticles from all sources; all microparticles induced similar Hh-dependent changes in SEC gene expression. SEC from healthy livers did not express Hh target genes or activation markers, but both were up-regulated in SEC after BDL. Hh-containing exosome-enriched microparticles released from liver cells alter hepatic SEC gene expression, suggesting a novel mechanism for cirrhotic vasculopathy.

  19. Targeted modulation of reactive oxygen species in the vascular endothelium.

    Science.gov (United States)

    Shuvaev, Vladimir V; Muzykantov, Vladimir R

    2011-07-15

    'Endothelial cells lining vascular luminal surface represent an important site of signaling and injurious effects of reactive oxygen species (ROS) produced by other cells and endothelium itself in ischemia, inflammation and other pathological conditions. Targeted delivery of ROS modulating enzymes conjugated with antibodies to endothelial surface molecules (vascular immunotargeting) provides site-specific interventions in the endothelial ROS, unattainable by other formulations including PEG-modified enzymes. Targeting of ROS generating enzymes (e.g., glucose oxidase) provides ROS- and site-specific models of endothelial oxidative stress, whereas targeting of antioxidant enzymes SOD and catalase offers site-specific quenching of superoxide anion and H(2)O(2). These targeted antioxidant interventions help to clarify specific role of endothelial ROS in vascular and pulmonary pathologies and provide basis for design of targeted therapeutics for treatment of these pathologies. In particular, antibody/catalase conjugates alleviate acute lung ischemia/reperfusion injury, whereas antibody/SOD conjugates inhibit ROS-mediated vasoconstriction and inflammatory endothelial signaling. Encapsulation in protease-resistant, ROS-permeable carriers targeted to endothelium prolongs protective effects of antioxidant enzymes, further diversifying the means for targeted modulation of endothelial ROS. Copyright © 2011 Elsevier B.V. All rights reserved.

  20. Obligatory participation of macrophages in an angiopoietin 2-mediated cell death switch

    OpenAIRE

    Rao, Sujata; Lobov, Ivan B.; Vallance, Jefferson E.; Tsujikawa, Kaoru; Shiojima, Ichiro; Akunuru, Shailaja; Walsh, Kenneth; Benjamin, Laura E.; Lang, Richard A.

    2007-01-01

    Macrophages have a critical function in the recognition and engulfment of dead cells. In some settings, macrophages also actively signal programmed cell death. Here we show that during developmentally scheduled vascular regression, resident macrophages are an obligatory participant in a signaling switch that favors death over survival. This switch occurs when the signaling ligand angiopoietin 2 has the dual effect of suppressing survival signaling in vascular endothelial cells (VECs) and stim...

  1. IGF-1 Has Plaque-Stabilizing Effects in Atherosclerosis by Altering Vascular Smooth Muscle Cell Phenotype

    Science.gov (United States)

    von der Thüsen, Jan H.; Borensztajn, Keren S.; Moimas, Silvia; van Heiningen, Sandra; Teeling, Peter; van Berkel, Theo J.C.; Biessen, Erik A.L.

    2011-01-01

    Insulin-like growth factor-1 (IGF-1) signaling is important for the maintenance of plaque stability in atherosclerosis due to its effects on vascular smooth muscle cell (vSMC) phenotype. To investigate this hypothesis, we studied the effects of the highly inflammatory milieu of the atherosclerotic plaque on IGF-1 signaling and stability-related phenotypic parameters of murine vSMCs in vitro, and the effects of IGF-1 supplementation on plaque phenotype in an atherosclerotic mouse model. M1-polarized, macrophage-conditioned medium inhibited IGF-1 signaling by ablating IGF-1 and increasing IGF-binding protein 3, increased vSMC apoptosis, and decreased proliferation. Expression of α-actin and col3a1 genes was strongly attenuated by macrophage-conditioned medium, whereas expression of matrix-degrading enzymes was increased. Importantly, all of these effects could be corrected by supplementation with IGF-1. In vivo, treatment with the stable IGF-1 analog Long R3 IGF-1 in apolipoprotein E knockout mice reduced stenosis and core size, and doubled cap/core ratio in early atherosclerosis. In advanced plaques, Long R3 IGF-1 increased the vSMC content of the plaque by more than twofold and significantly reduced the rate of intraplaque hemorrhage. We believe that IGF-1 in atherosclerotic plaques may have a role in preventing plaque instability, not only by modulating smooth muscle cell turnover, but also by altering smooth muscle cell phenotype. PMID:21281823

  2. Temporal protein expression pattern in intracellular signalling ...

    Indian Academy of Sciences (India)

    2015-09-28

    Sep 28, 2015 ... targets for the treatment of various T-cells, immune-related diseases. We hope ... signifies the alternative routes of signal propagation. The molecules kept in ...... growth factor, mitogens for vascular cells and fibroblasts: dif- ferential ..... tumor necrosis factor contributes to CD8(+) T cell survival in the transition ...

  3. Contact-mediated and humoral communication between vascular endothelial and smooth muscle cells in vitro

    International Nuclear Information System (INIS)

    Davies, P.F.

    1986-01-01

    Vascular endothelial cells (EC) and smooth muscle cells (SMC) co-exist in close apposition to each other in all blood vessels except capillaries. Investigations of the metabolic interactions that may occur between these cells are essential to an understanding of vascular homeostasis and the pathogenesis of atherosclerosis. The authors have developed two in vitro models of co-temporal vascular cell communication. The first facilitates reversible microcarrier-mediated gap junctional communication between EC and SMC monolayers. When either EC or SMC were prelabelled with 3 H-uridine, intracellular nucleotide rapidly transferred across the region of heterocellular attachment to the complementary cell population. Cytoplasmic continuity between EC and SMC allowed metabolic cooperation via ions and small molecules (<1.5 KD). Thus, vascular reactivity, particularly in the microcirculation where myoendothelial gap junctions have been observed, may involve cytoplasmic second messengers transported from EC to SMC. In the second model, humoral communication was established between separated cultures of EC and SMC which shared the same culture medium. Endothelial-specific stimulation of SMC growth and lipoprotein metabolism via soluble factors was demonstrated. Two mechanisms of stimulation of SMC lipoprotein metabolism were identified; one endothelial derived mitogen-dependent, the other mitogen-independent which was mediated via low molecular weight endothelial cell products

  4. Suppression of vascular smooth muscle cells' proliferation and ...

    African Journals Online (AJOL)

    This study aimed to determine the effects of valsartan on the proliferation and migration of isolated rat vascular smooth muscle cells (VSMCs) and the expression of phospho-p42/44 mitogen-activated protein kinase (MAPK) promoted by angiotensin II (Ang II). VSMCs from the rat thoracic aorta were cultured by ...

  5. Proangiogenic hematopoietic cells of monocytic origin: roles in vascular regeneration and pathogenic processes of systemic sclerosis.

    Science.gov (United States)

    Yamaguchi, Yukie; Kuwana, Masataka

    2013-02-01

    New blood vessel formation is critical, not only for organ development and tissue regeneration, but also for various pathologic processes, such as tumor development and vasculopathy. The maintenance of the postnatal vascular system requires constant remodeling, which occurs through angiogenesis, vasculogenesis, and arteriogenesis. Vasculogenesis is mediated by the de novo differentiation of mature endothelial cells from endothelial progenitor cells (EPCs). Early studies provided evidence that bone marrow-derived CD14⁺ monocytes can serve as a subset of EPCs because of their expression of endothelial markers and ability to promote neovascularization in vitro and in vivo. However, the current consensus is that monocytic cells do not give rise to endothelial cells in vivo, but function as support cells, by promoting vascular formation and repair through their immediate recruitment to the site of vascular injury, secretion of proangiogenic factors, and differentiation into mural cells. These monocytes that function in a supporting role in vascular repair are now termed monocytic pro-angiogenic hematopoietic cells (PHCs). Systemic sclerosis (SSc) is a multisystem connective tissue disease characterized by excessive fibrosis and microvasculopathy, along with poor vascular formation and repair. We recently showed that in patients with SSc, circulating monocytic PHCs increase dramatically and have enhanced angiogenic potency. These effects may be induced in response to defective vascular repair machinery. Since CD14⁺ monocytes can also differentiate into fibroblast-like cells that produce extracellular matrix proteins, here we propose a new hypothesis that aberrant monocytic PHCs, once mobilized into circulation, may also contribute to the fibrotic process of SSc.

  6. Vascular smooth muscle cell stiffness and adhesion to collagen I modified by vasoactive agonists.

    Directory of Open Access Journals (Sweden)

    Zhongkui Hong

    Full Text Available In vascular smooth muscle cells (VSMCs integrin-mediated adhesion to extracellular matrix (ECM proteins play important roles in sustaining vascular tone and resistance. The main goal of this study was to determine whether VSMCs adhesion to type I collagen (COL-I was altered in parallel with the changes in the VSMCs contractile state induced by vasoconstrictors and vasodilators. VSMCs were isolated from rat cremaster skeletal muscle arterioles and maintained in primary culture without passage. Cell adhesion and cell E-modulus were assessed using atomic force microscopy (AFM by repetitive nano-indentation of the AFM probe on the cell surface at 0.1 Hz sampling frequency and 3200 nm Z-piezo travelling distance (approach and retraction. AFM probes were tipped with a 5 μm diameter microbead functionalized with COL-I (1 mg\\ml. Results showed that the vasoconstrictor angiotensin II (ANG-II; 10-6 significantly increased (p<0.05 VSMC E-modulus and adhesion probability to COL-I by approximately 35% and 33%, respectively. In contrast, the vasodilator adenosine (ADO; 10-4 significantly decreased (p<0.05 VSMC E-modulus and adhesion probability by approximately -33% and -17%, respectively. Similarly, the NO donor (PANOate, 10-6 M, a potent vasodilator, also significantly decreased (p<0.05 the VSMC E-modulus and COL-I adhesion probability by -38% and -35%, respectively. These observations support the hypothesis that integrin-mediated VSMC adhesion to the ECM protein COL-I is dynamically regulated in parallel with VSMC contractile activation. These data suggest that the signal transduction pathways modulating VSMC contractile activation and relaxation, in addition to ECM adhesion, interact during regulation of contractile state.

  7. GPR68 Senses Flow and Is Essential for Vascular Physiology.

    Science.gov (United States)

    Xu, Jie; Mathur, Jayanti; Vessières, Emilie; Hammack, Scott; Nonomura, Keiko; Favre, Julie; Grimaud, Linda; Petrus, Matt; Francisco, Allain; Li, Jingyuan; Lee, Van; Xiang, Fu-Li; Mainquist, James K; Cahalan, Stuart M; Orth, Anthony P; Walker, John R; Ma, Shang; Lukacs, Viktor; Bordone, Laura; Bandell, Michael; Laffitte, Bryan; Xu, Yan; Chien, Shu; Henrion, Daniel; Patapoutian, Ardem

    2018-04-19

    Mechanotransduction plays a crucial role in vascular biology. One example of this is the local regulation of vascular resistance via flow-mediated dilation (FMD). Impairment of this process is a hallmark of endothelial dysfunction and a precursor to a wide array of vascular diseases, such as hypertension and atherosclerosis. Yet the molecules responsible for sensing flow (shear stress) within endothelial cells remain largely unknown. We designed a 384-well screening system that applies shear stress on cultured cells. We identified a mechanosensitive cell line that exhibits shear stress-activated calcium transients, screened a focused RNAi library, and identified GPR68 as necessary and sufficient for shear stress responses. GPR68 is expressed in endothelial cells of small-diameter (resistance) arteries. Importantly, Gpr68-deficient mice display markedly impaired acute FMD and chronic flow-mediated outward remodeling in mesenteric arterioles. Therefore, GPR68 is an essential flow sensor in arteriolar endothelium and is a critical signaling component in cardiovascular pathophysiology. Copyright © 2018 Elsevier Inc. All rights reserved.

  8. Control of Vascular Smooth Muscle Cell Growth by Connexin 43

    Directory of Open Access Journals (Sweden)

    Chintamani eJoshi

    2012-06-01

    Full Text Available Connexin 43 (Cx43, the principal gap junction protein in vascular smooth muscle cells (VSMCs, regulates movement of ions and other signaling molecules through gap junction intercellular communication (GJIC and plays important roles in maintaining normal vessel function; however, many of the signaling mechanisms controlling Cx43 in VSMCs are not clearly described. The goal of this study was to investigate mechanisms of Cx43 regulation with respect to VSMC proliferation. Treatment of rat primary VSMCs with the cAMP analog 8Br-cAMP, the soluble guanylate cyclase (sGC stimulator BAY 41-2272 (BAY, or the Cx inducer diallyl disulfide (DADS significantly reduced proliferation after 72 h compared to vehicle controls. Bromodeoxyuridine uptake revealed reduction (p<.001 in DNA synthesis after 6 h and flow cytometry showed reduced (40% S phase cell numbers after 16 h in DADS-treated cells compared to controls. Cx43 expression significantly increased after 270 min treatment with 8Br-cAMP, 8Br-cGMP, BAY or DADS. Inhibition of PKA, PKG or PKC reversed 8Br-cAMP-stimulated increases in Cx43 expression, whereas only PKG or PKC inhibition reversed 8Br-cGMP- and BAY-stimulated increases in total Cx43. Interestingly, stimulation of Cx43 expression by DADS was not dependent on PKA, PKG or PKC. Using fluorescence recovery after photobleaching, only 8Br-cAMP or DADS increased GJIC with 8Br-cAMP mediated by PKC and DADS mediated by PKG. Further, DADS significantly increased phosphorylation at the MAPK-sensitive serine (Ser255 and Ser279, the cell cycle regulatory kinase-sensitive Ser262 and the PKC-sensitive Ser368 after 30 min while 8Br-cAMP significantly increased phosphorylation only at Ser279 compared to controls. This study demonstrates that 8Br-cAMP- and DADS-enhanced GJIC rather than Cx43 expression and/or phosphorylation plays an important role in regulation of VSMC proliferation and provides new insights into the growth-regulatory capacities of Cx43 in VSMCs.

  9. Compressive Elasticity of Three-Dimensional Nanofiber Matrix Directs Mesenchymal Stem Cell Differentiation to Vascular Cells with Endothelial or Smooth Muscle Cell Markers

    OpenAIRE

    Wingate, Kathryn; Bonani, Walter; Tan, Yan; Bryant, Stephanie J.; Tan, Wei

    2012-01-01

    The importance of mesenchymal stem cell (MSC) in vascular regeneration is becoming increasingly recognized. However, few in vitro studies have been performed to identify the effects of environmental elasticity on the differentiation of MSC into vascular cell types. We utilized electrospinning and photopolymerization techniques to fabricate a 3D PEGdma nanofiber hydrogel matrix with a tunable elasticity for use as a cellular substrate. Compression testing demonstrated that the elastic modulus ...

  10. Role of PD 0332991 on the Proliferation and Apoptosis of Vascular Endothelial Cells

    Directory of Open Access Journals (Sweden)

    Chenlong ZHAO

    2018-05-01

    Full Text Available Background and objective Angiogenesis is an important process in the development of tumor. PD 0332991, a cell cycle inhibitor, can specifically inhibit CD4/6 phosphorylation and cell cycle progression. In xeongraft mice models, PD 0332991 treated mice had significantly decreased angiogenesis and vascular density compared with the control group, but the mechanism remains unknown. The purpose of this study is to investigate the role and molecular mechanism of PD 0332991 on vascular endothelial cells. Methods EA.hy926 cells, a kind of vascular endothelial cell, were used as the research model. The effects of PD 0332991 on the activity and proliferation of EA.hy926 cells were detected by the MTT, EdU assays. Wound-healing assays and transwell assays were used to determine the effects of PD 0332991 on the mobility of EA.hy926. The influence of PD 0332991 on cell cycle and apoptosis of endothelial cells was tested by flow cytometry, and the Western blot was applied to observe the expression of cell cycle related proteins in EA.hy926 cells treated by PD 0332991. Results PD 0332991 significantly inhibited the proliferation and mobility of EA.hy926 cells, caused cell cycle arrest and apoptosis. At the same time, PD 0332991 inhibited the expression of CDK4/6 and phosphorylation of Rb, and thus inhibited the cell cycle progression of EA.hy926 cells. Conclusion PD 0332991 can inhibit the proliferation and activity of endothelial cells and induces apoptosis.

  11. Vascular endothelial dysfunction in β-thalassemia occurs despite increased eNOS expression and preserved vascular smooth muscle cell reactivity to NO.

    Directory of Open Access Journals (Sweden)

    Ekatherina Stoyanova

    Full Text Available The hereditary β-thalassemia major condition requires regular lifelong blood transfusions. Transfusion-related iron overloading has been associated with the onset of cardiovascular complications, including cardiac dysfunction and vascular anomalies. By using an untransfused murine model of β-thalassemia major, we tested the hypothesis that vascular endothelial dysfunction, alterations of arterial structure and of its mechanical properties would occur despite the absence of treatments.Vascular function and structure were evaluated ex vivo. Compared to the controls, endothelium-dependent vasodilation with acetylcholine was blunted in mesenteric resistance arteries of β-thalassemic mice while the endothelium-independent vasodilator (sodium nitroprusside produced comparable vessel dilation, indicating endothelial cell impairment with preserved smooth muscle cell reactivity to nitric oxide (NO. While these findings suggest a decrease in NO bioavailability, Western blotting showed heightened expression of aortic endothelial NO synthase (eNOS in β-thalassemia. Vascular remodeling of the common carotid arteries revealed increased medial elastin content. Under isobaric conditions, the carotid arteries of β-thalassemic mice exhibited decreased wall stress and softening due to structural changes of the vessel wall.A complex vasculopathy was identified in untransfused β-thalassemic mice characterized by altered carotid artery structure and endothelial dysfunction of resistance arterioles, likely attributable to reduced NO bioavailability despite enhanced vascular eNOS expression.

  12. A Robust Method to Generate Mechanically Anisotropic Vascular Smooth Muscle Cell Sheets for Vascular Tissue Engineering.

    Science.gov (United States)

    Backman, Daniel E; LeSavage, Bauer L; Shah, Shivem B; Wong, Joyce Y

    2017-06-01

    In arterial tissue engineering, mimicking native structure and mechanical properties is essential because compliance mismatch can lead to graft failure and further disease. With bottom-up tissue engineering approaches, designing tissue components with proper microscale mechanical properties is crucial to achieve the necessary macroscale properties in the final implant. This study develops a thermoresponsive cell culture platform for growing aligned vascular smooth muscle cell (VSMC) sheets by photografting N-isopropylacrylamide (NIPAAm) onto micropatterned poly(dimethysiloxane) (PDMS). The grafting process is experimentally and computationally optimized to produce PNIPAAm-PDMS substrates optimal for VSMC attachment. To allow long-term VSMC sheet culture and increase the rate of VSMC sheet formation, PNIPAAm-PDMS surfaces were further modified with 3-aminopropyltriethoxysilane yielding a robust, thermoresponsive cell culture platform for culturing VSMC sheets. VSMC cell sheets cultured on patterned thermoresponsive substrates exhibit cellular and collagen alignment in the direction of the micropattern. Mechanical characterization of patterned, single-layer VSMC sheets reveals increased stiffness in the aligned direction compared to the perpendicular direction whereas nonpatterned cell sheets exhibit no directional dependence. Structural and mechanical anisotropy of aligned, single-layer VSMC sheets makes this platform an attractive microstructural building block for engineering a vascular graft to match the in vivo mechanical properties of native arterial tissue. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Classification of vascular function in upper limb using bilateral photoplethysmographic signals

    International Nuclear Information System (INIS)

    Shariati, Nastaran Hesam; Zahedi, Edmond; Jajai, Hassan Mansouri

    2008-01-01

    Bilateral PPG signals have been used for comparative study of two groups of healthy (free from any cardiovascular risk factors) and diabetic (as cardiovascular disease risk group) subjects in the age-matched range 40–50 years. The peripheral blood pulsations were recorded simultaneously from right and left index fingers for 90 s. Pulses have been modeled with the ARX440 model in the interval of 300 sample points with 100 sample points overlap between segments. Model parameters of three segments based on the highest fitness (higher than 80%) of modeled segments were retained for each subject. Subsequently, principal component analysis (PCA) was applied to the parameters of retained segments to eliminate the existing correlation among parameters and provide uncorrelated variables. The first principal component (contains 78.2% variance of data) was significantly greater in diabetic than in control groups (P < 0.0001, 0.74 ± 2.01 versus −0.53 ± 1.66). In addition the seventh principal component, which contains 0.02% of the data variance, was significantly lower in diabetic than in control groups (P < 0.05, −0.007 ± 0.03 versus 0.005 ± 0.03). Finally, linear discrimination analysis (LDA) was used to classify the subjects. The classification was done using the robust leaving-one-subject-out method. LDA could classify the subjects with 71.7% sensitivity and 70.2% specificity while the male subjects resulted in a highly acceptable result for the sensitivity (81%). The present study showed that PPG signals can be used for vascular function assessment and may find further application for detection of vascular changes before onset of clinical diseases

  14. Cloning and characterization of rat density-enhanced phosphatase-1, a protein tyrosine phosphatase expressed by vascular cells.

    Science.gov (United States)

    Borges, L G; Seifert, R A; Grant, F J; Hart, C E; Disteche, C M; Edelhoff, S; Solca, F F; Lieberman, M A; Lindner, V; Fischer, E H; Lok, S; Bowen-Pope, D F

    1996-09-01

    We have cloned from cultured vascular smooth muscle cells a protein tyrosine phosphatase, rat density-enhanced phosphatase-1 (rDEP-1), which is a probable rat homologue of DEP-1/HPTP eta. rDEP-1 is encoded by an 8.7-kb transcript and is expressed as a 180- to 220-kD protein. The rDEP-1 gene is located on human chromosome 11 (region p11.2) and on mouse chromosome 2 (region 2E). The cDNA sequence predicts a transmembrane protein consisting of a single phosphatase catalytic domain in the intracellular region, a single transmembrane domain, and eight fibronectin type III repeats in the extracellular region (GenBank accession number U40790). In situ hybridization analysis demonstrates that rDEP-1 is widely expressed in vivo but that expression is highest in cells that form epithelioid monolayers. In cultured cells with epitheliod morphology, including endothelial cells and newborn smooth muscle cells, but not in fibroblast-like cells, rDEP-1 transcript levels are dramatically upregulated as population density increases. In vivo, quiescent endothelial cells in normal arteries express relatively high levels of rDEP-1. During repair of vascular injury, expression of rDEP-1 is downregulated in migrating and proliferating endothelial cells. In vivo, rDEP-1 transcript levels are present in very high levels in megakaryocytes, and circulating plates have high levels of the rDEP-1 protein. In vitro, initiation of differentiation of the human megakaryoblastic cell line CHRF-288-11 with phorbol 12-myristate 13-acetate leads to a very strong upregulation of rDEP-1 transcripts. The deduced structure and the regulation of expression of rDEP-1 suggest that it may play a role in adhesion and/or signaling events involving cell-cell and cell-matrix contact.

  15. An α-smooth muscle actin (acta2/αsma zebrafish transgenic line marking vascular mural cells and visceral smooth muscle cells.

    Directory of Open Access Journals (Sweden)

    Thomas R Whitesell

    Full Text Available Mural cells of the vascular system include vascular smooth muscle cells (SMCs and pericytes whose role is to stabilize and/or provide contractility to blood vessels. One of the earliest markers of mural cell development in vertebrates is α smooth muscle actin (acta2; αsma, which is expressed by pericytes and SMCs. In vivo models of vascular mural cell development in zebrafish are currently lacking, therefore we developed two transgenic zebrafish lines driving expression of GFP or mCherry in acta2-expressing cells. These transgenic fish were used to trace the live development of mural cells in embryonic and larval transgenic zebrafish. acta2:EGFP transgenic animals show expression that largely mirrors native acta2 expression, with early pan-muscle expression starting at 24 hpf in the heart muscle, followed by skeletal and visceral muscle. At 3.5 dpf, expression in the bulbus arteriosus and ventral aorta marks the first expression in vascular smooth muscle. Over the next 10 days of development, the number of acta2:EGFP positive cells and the number of types of blood vessels associated with mural cells increases. Interestingly, the mural cells are not motile and remain in the same position once they express the acta2:EGFP transgene. Taken together, our data suggests that zebrafish mural cells develop relatively late, and have little mobility once they associate with vessels.

  16. Vascular smooth muscle cells for use in vascular tissue engineering obtained by endothelial-to-mesenchymal transdifferentiation (EnMT) on collagen matrices

    NARCIS (Netherlands)

    Krenning, Guido; Moonen, Jan-Renier A. J.; van Luyn, Marja J. A.; Harmsen, Martin C.

    The discovery of the endothelial progenitor cell (EPC) has led to an intensive research effort into progenitor cell-based tissue engineering of (small-diameter) blood vessels. Herein, EPC are differentiated to vascular endothelial cells and serve as the inner lining of bioartificial vessels. As yet,

  17. Calcium Signaling in Taste Cells

    Science.gov (United States)

    Medler, Kathryn F.

    2014-01-01

    The sense of taste is a common ability shared by all organisms and is used to detect nutrients as well as potentially harmful compounds. Thus taste is critical to survival. Despite its importance, surprisingly little is known about the mechanisms generating and regulating responses to taste stimuli. All taste responses depend on calcium signals to generate appropriate responses which are relayed to the brain. Some taste cells have conventional synapses and rely on calcium influx through voltage-gated calcium channels. Other taste cells lack these synapses and depend on calcium release to formulate an output signal through a hemichannel. Beyond establishing these characteristics, few studies have focused on understanding how these calcium signals are formed. We identified multiple calcium clearance mechanisms that regulate calcium levels in taste cells as well as a calcium influx that contributes to maintaining appropriate calcium homeostasis in these cells. Multiple factors regulate the evoked taste signals with varying roles in different cell populations. Clearly, calcium signaling is a dynamic process in taste cells and is more complex than has previously been appreciated. PMID:25450977

  18. Phosphodiesterase 1 regulation is a key mechanism in vascular aging

    DEFF Research Database (Denmark)

    Niño, Paula K Bautista; Durik, Matej; Danser, A H Jan

    2015-01-01

    Reduced nitric oxide (NO)/cGMP signalling is observed in age-related vascular disease. We hypothesize that this disturbed signalling involves effects of genomic instability, a primary causal factor in aging, on vascular smooth muscle cells (VSMCs) and that the underlying mechanism plays a role...... in human age-related vascular disease. To test our hypothesis, we combined experiments in mice with genomic instability resulting from the defective nucleotide excision repair gene ERCC1 (Ercc1(d/-) mice), human VSMC cultures and population genome-wide association studies (GWAS). Aortic rings of Ercc1(d...... in lungs was higher in Ercc1(d/-) mice. No differences in activity or levels of cGMP-dependent protein kinase 1 or sGC were observed in Ercc1(d/-) mice compared with WT. Senescent human VSMC showed elevated PDE1A and PDE1C and PDE5 mRNA levels (11.6-, 9- and 2.3-fold respectively), which associated...

  19. Role of epidermal growth factor receptor and endoplasmic reticulum stress in vascular remodeling induced by angiotensin II.

    Science.gov (United States)

    Takayanagi, Takehiko; Kawai, Tatsuo; Forrester, Steven J; Obama, Takashi; Tsuji, Toshiyuki; Fukuda, Yamato; Elliott, Katherine J; Tilley, Douglas G; Davisson, Robin L; Park, Joon-Young; Eguchi, Satoru

    2015-06-01

    The mechanisms by which angiotensin II (AngII) elevates blood pressure and enhances end-organ damage seem to be distinct. However, the signal transduction cascade by which AngII specifically mediates vascular remodeling such as medial hypertrophy and perivascular fibrosis remains incomplete. We have previously shown that AngII-induced epidermal growth factor receptor (EGFR) transactivation is mediated by disintegrin and metalloproteinase domain 17 (ADAM17), and that this signaling is required for vascular smooth muscle cell hypertrophy but not for contractile signaling in response to AngII. Recent studies have implicated endoplasmic reticulum (ER) stress in hypertension. Interestingly, EGFR is capable of inducing ER stress. The aim of this study was to test the hypothesis that activation of EGFR and ER stress are critical components required for vascular remodeling but not hypertension induced by AngII. Mice were infused with AngII for 2 weeks with or without treatment of EGFR inhibitor, erlotinib, or ER chaperone, 4-phenylbutyrate. AngII infusion induced vascular medial hypertrophy in the heart, kidney and aorta, and perivascular fibrosis in heart and kidney, cardiac hypertrophy, and hypertension. Treatment with erlotinib as well as 4-phenylbutyrate attenuated vascular remodeling and cardiac hypertrophy but not hypertension. In addition, AngII infusion enhanced ADAM17 expression, EGFR activation, and ER/oxidative stress in the vasculature, which were diminished in both erlotinib-treated and 4-phenylbutyrate-treated mice. ADAM17 induction and EGFR activation by AngII in vascular cells were also prevented by inhibition of EGFR or ER stress. In conclusion, AngII induces vascular remodeling by EGFR activation and ER stress via a signaling mechanism involving ADAM17 induction independent of hypertension. © 2015 American Heart Association, Inc.

  20. Signaling profiling at the single-cell level identifies a distinct signaling signature in murine hematopoietic stem cells.

    Science.gov (United States)

    Du, Juan; Wang, Jinyong; Kong, Guangyao; Jiang, Jing; Zhang, Jingfang; Liu, Yangang; Tong, Wei; Zhang, Jing

    2012-07-01

    Hematopoietic stem cell (HSC) function is tightly regulated by cytokine signaling. Although phospho-flow cytometry allows us to study signaling in defined populations of cells, there has been tremendous hurdle to carry out this study in rare HSCs due to unrecoverable critical HSC markers, low HSC number, and poor cell recovery rate. Here, we overcame these difficulties and developed a "HSC phospho-flow" method to analyze cytokine signaling in murine HSCs at the single-cell level and compare HSC signaling profile to that of multipotent progenitors (MPPs), a cell type immediately downstream of HSCs, and commonly used Lin(-) cKit(+) cells (LK cells, enriched for myeloid progenitors). We chose to study signaling evoked from three representative cytokines, stem cell factor (SCF) and thrombopoietin (TPO) that are essential for HSC function and granulocyte macrophage-colony-stimulating factor (GM-CSF) that is dispensable for HSCs. HSCs display a distinct TPO and GM-CSF signaling signature from MPPs and LK cells, which highly correlates with receptor surface expression. In contrast, although majority of LK cells express lower levels of cKit than HSCs and MPPs, SCF-evoked ERK1/2 activation in LK cells shows a significantly increased magnitude for a prolonged period. These results suggest that specific cellular context plays a more important role than receptor surface expression in SCF signaling. Our study of HSC signaling at the homeostasis stage paves the way to investigate signaling changes in HSCs under conditions of stress, aging, and hematopoietic diseases. Copyright © 2012 AlphaMed Press.

  1. Role of UBIAD1 in Intracellular Cholesterol Metabolism and Vascular Cell Calcification.

    Directory of Open Access Journals (Sweden)

    Sha Liu

    Full Text Available Vascular calcification is an important risk factor associated with mortality among patients with chronic kidney disease. Intracellular cholesterol metabolism is involved in the process of vascular cell calcification. In this study, we investigated the role of UbiA prenyltransferase domain containing 1 (UBIAD1 in intracellular cholesterol metabolism and vascular cell calcification, and identified its subcellular location. Primary human umbilical vein smooth muscle cells (HUVSMCs were incubated with either growth medium (1.4 mmol/L Pi or calcification medium (CM (3.0 mmol/L Pi. Under treatment with CM, HUVSMCs were further incubated with exogenous cholesterol, or menaquinone-4, a product of UBIAD1. The plasmid and small interfering RNA were transfected in HUVSMCs to alter the expression of UBIAD1. Matrix calcium quantitation, alkaline phosphatase activity, intracellular cholesterol level and menaquinone-4 level were measured. The expression of several genes involved in cholesterol metabolism were analyzed. Using an anti-UBIAD1 antibody, an endoplasmic reticulum marker and a Golgi marker, the subcellular location of UBIAD1 in HUVSMCs was analyzed. CM increased matrix calcium, alkaline phosphatase activity and intracellular cholesterol level, and reduced UBIAD1 expression and menaquinone-4 level. Addition of cholesterol contributed to increased matrix calcification and alkaline phosphatase activity in a dose-dependent manner. Elevated expression of UBIAD1 or menaquinone-4 in HUVSMCs treated with CM significantly reduced intracellular cholesterol level, matrix calcification and alkaline phosphatase activity, but increased menaquinone-4 level. Elevated expression of UBIAD1 or menaquinone-4 reduced the gene expression of sterol regulatory element-binding protein-2, and increased gene expression of ATP binding cassette transporters A1, which are in charge of cholesterol synthesis and efflux. UBIAD1 co-localized with the endoplasmic reticulum marker and

  2. Ubiquitin carboxyl terminal hydrolase L1 negatively regulates TNFα-mediated vascular smooth muscle cell proliferation via suppressing ERK activation

    International Nuclear Information System (INIS)

    Ichikawa, Tomonaga; Li, Jinqing; Dong, Xiaoyu; Potts, Jay D.; Tang, Dong-Qi; Li, Dong-Sheng; Cui, Taixing

    2010-01-01

    Deubiquitinating enzymes (DUBs) appear to be critical regulators of a multitude of processes such as proliferation, apoptosis, differentiation, and inflammation. We have recently demonstrated that a DUB of ubiquitin carboxyl terminal hydrolase L1 (UCH-L1) inhibits vascular lesion formation via suppressing inflammatory responses in vasculature. However, the precise underlying mechanism remains to be defined. Herein, we report that a posttranscriptional up-regulation of UCH-L1 provides a negative feedback to tumor necrosis factor alpha (TNFα)-mediated activation of extracellular signal-regulated kinases (ERK) and proliferation in vascular smooth muscle cells (VSMCs). In rat adult VSMCs, adenoviral over-expression of UCH-L1 inhibited TNFα-induced activation of ERK and DNA synthesis. In contrast, over-expression of UCH-L1 did not affect platelet derived growth factor (PDGF)-induced VSMC proliferation and activation of growth stimulating cascades including ERK. TNFα hardly altered UCH-L1 mRNA expression and stability; however, up-regulated UCH-L1 protein expression via increasing UCH-L1 translation. These results uncover a novel mechanism by which UCH-L1 suppresses vascular inflammation.

  3. Protein kinase A-alpha directly phosphorylates FoxO1 in vascular endothelial cells to regulate expression of vascular cellular adhesion molecule-1 mRNA.

    Science.gov (United States)

    Lee, Ji-Won; Chen, Hui; Pullikotil, Philomena; Quon, Michael J

    2011-02-25

    FoxO1, a forkhead box O class transcription factor, is abundant in insulin-responsive tissues. Akt, downstream from phosphatidylinositol 3-kinase in insulin signaling, phosphorylates FoxO1 at Thr(24), Ser(256), and Ser(319), negatively regulating its function. We previously reported that dehydroepiandrosterone-stimulated phosphorylation of FoxO1 in endothelial cells requires cAMP-dependent protein kinase α (PKA-α). Therefore, we hypothesized that FoxO1 is a novel direct substrate for PKA-α. Using an immune complex kinase assay with [γ-(32)P]ATP, purified PKA-α directly phosphorylated wild-type FoxO1 but not FoxO1-AAA (mutant with alanine substitutions at known Akt phosphorylation sites). Phosphorylation of wild-type FoxO1 (but not FoxO1-AAA) was detectable using phospho-specific antibodies. Similar results were obtained using purified GST-FoxO1 protein as the substrate. Thus, FoxO1 is a direct substrate for PKA-α in vitro. In bovine aortic endothelial cells, interaction between endogenous PKA-α and endogenous FoxO1 was detected by co-immunoprecipitation. In human aortic endothelial cells (HAEC), pretreatment with H89 (PKA inhibitor) or siRNA knockdown of PKA-α decreased forskolin- or prostaglandin E(2)-stimulated phosphorylation of FoxO1. In HAEC transfected with a FoxO-promoter luciferase reporter, co-expression of the catalytic domain of PKA-α, catalytically inactive mutant PKA-α, or siRNA against PKA-α caused corresponding increases or decreases in transactivation of the FoxO promoter. Expression of vascular cellular adhesion molecule-1 mRNA, up-regulated by FoxO1 in endothelial cells, was enhanced by siRNA knockdown of PKA-α or treatment of HAEC with the PKA inhibitor H89. Adhesion of monocytes to endothelial cells was enhanced by H89 treatment or overexpression of FoxO1-AAA, similar to effects of TNF-α treatment. We conclude that FoxO1 is a novel physiological substrate for PKA-α in vascular endothelial cells.

  4. Low Immunogenic Endothelial Cells Maintain Morphological and Functional Properties Required for Vascular Tissue Engineering.

    Science.gov (United States)

    Lau, Skadi; Eicke, Dorothee; Carvalho Oliveira, Marco; Wiegmann, Bettina; Schrimpf, Claudia; Haverich, Axel; Blasczyk, Rainer; Wilhelmi, Mathias; Figueiredo, Constança; Böer, Ulrike

    2018-03-01

    The limited availability of native vessels suitable for the application as hemodialysis shunts or bypass material demands new strategies in cardiovascular surgery. Tissue-engineered vascular grafts containing autologous cells are considered ideal vessel replacements due to the low risk of rejection. However, endothelial cells (EC), which are central components of natural blood vessels, are difficult to obtain from elderly patients of poor health. Umbilical cord blood represents a promising alternative source for EC, but their allogeneic origin corresponds with the risk of rejection after allotransplantation. To reduce this risk, the human leukocyte antigen class I (HLA I) complex was stably silenced by lentiviral vector-mediated RNA interference (RNAi) in EC from peripheral blood and umbilical cord blood and vein. EC from all three sources were transduced by 93.1% ± 4.8% and effectively, HLA I-silenced by up to 67% compared to nontransduced (NT) cells or transduced with a nonspecific short hairpin RNA, respectively. Silenced EC remained capable to express characteristic endothelial surface markers such as CD31 and vascular endothelial cadherin important for constructing a tight barrier, as well as von Willebrand factor and endothelial nitric oxide synthase important for blood coagulation and vessel tone regulation. Moreover, HLA I-silenced EC were still able to align under unidirectional flow, to take up acetylated low-density lipoprotein, and to form capillary-like tube structures in three-dimensional fibrin gels similar to NT cells. In particular, addition of adipose tissue-derived mesenchymal stem cells significantly improved tube formation capability of HLA I-silenced EC toward long and widely branched vascular networks necessary for prevascularizing vascular grafts. Thus, silencing HLA I by RNAi represents a promising technique to reduce the immunogenic potential of EC from three different sources without interfering with EC-specific morphological and

  5. Construction of a fucoidan/laminin functional multilayer to direction vascular cell fate and promotion hemocompatibility

    International Nuclear Information System (INIS)

    Ye, Changrong; Wang, Yan; Su, Hong; Yang, Ping; Huang, Nan; Maitz, Manfred F.; Zhao, Anshan

    2016-01-01

    Surface biofunctional modification of cardiovascular stents is a versatile approach to reduce the adverse effects after implantation. In this work, a novel multifunctional coating was fabricated by coimmobilization of the sulfated polysaccharide of brown algae fucoidan and laminin to biomimic the vascular intimal conditions in order to support rapid endothelialization, prevent restenosis and improve hemocompatibility. The surface properties of the coating such as hydrophilicity, bonding density of biomolecules and stability were evaluated and optimized. According to the biocompatibility tests, the fucoidan/laminin multilayer coated surface displayed less platelet adhesion with favorable anticoagulant property. In addition, the fucoidan/laminin complex showed function to selectively regulate vascular cells growth behavior. The proliferation of endothelial cells (ECs) on the fucoidan/laminin biofunctional coating was significantly promoted. For the smooth muscle cells (SMCs), inhibitory effects on cell adhesion and proliferation were observed. In conclusion, the fucoidan/laminin biofunctional coating was successfully fabricated with desirable anticoagulant and endothelialization properties which show a promising application in the vascular devices such as vascular stents or grafts surface modification. - Highlights: • Construction of fucoidan/laminin functional multilayer to biomimic the basement membrane of vascular • The fucoidan/laminin complex demonstrates anti-coagulation property. • The fucoidan/laminin complex can selectively regulate EC and SMC growth behavior to prevent restenosis.

  6. Construction of a fucoidan/laminin functional multilayer to direction vascular cell fate and promotion hemocompatibility

    Energy Technology Data Exchange (ETDEWEB)

    Ye, Changrong; Wang, Yan; Su, Hong; Yang, Ping; Huang, Nan [Key Laboratory of Advanced Materials Technology of Ministry of Education, Department of Materials Science and Engineering, Southwest Jiaotong University, Chengdu 610031 (China); Maitz, Manfred F. [Leibniz Institute of Polymer Research Dresden, Max Bergmann Center of Biomaterials Dresden, Dresden 01069 (Germany); Zhao, Anshan [Key Laboratory of Advanced Materials Technology of Ministry of Education, Department of Materials Science and Engineering, Southwest Jiaotong University, Chengdu 610031 (China)

    2016-07-01

    Surface biofunctional modification of cardiovascular stents is a versatile approach to reduce the adverse effects after implantation. In this work, a novel multifunctional coating was fabricated by coimmobilization of the sulfated polysaccharide of brown algae fucoidan and laminin to biomimic the vascular intimal conditions in order to support rapid endothelialization, prevent restenosis and improve hemocompatibility. The surface properties of the coating such as hydrophilicity, bonding density of biomolecules and stability were evaluated and optimized. According to the biocompatibility tests, the fucoidan/laminin multilayer coated surface displayed less platelet adhesion with favorable anticoagulant property. In addition, the fucoidan/laminin complex showed function to selectively regulate vascular cells growth behavior. The proliferation of endothelial cells (ECs) on the fucoidan/laminin biofunctional coating was significantly promoted. For the smooth muscle cells (SMCs), inhibitory effects on cell adhesion and proliferation were observed. In conclusion, the fucoidan/laminin biofunctional coating was successfully fabricated with desirable anticoagulant and endothelialization properties which show a promising application in the vascular devices such as vascular stents or grafts surface modification. - Highlights: • Construction of fucoidan/laminin functional multilayer to biomimic the basement membrane of vascular • The fucoidan/laminin complex demonstrates anti-coagulation property. • The fucoidan/laminin complex can selectively regulate EC and SMC growth behavior to prevent restenosis.

  7. Protein Kinase C Inhibitors as Modulators of Vascular Function and Their Application in Vascular Disease

    Directory of Open Access Journals (Sweden)

    Raouf A. Khalil

    2013-03-01

    Full Text Available Blood pressure (BP is regulated by multiple neuronal, hormonal, renal and vascular control mechanisms. Changes in signaling mechanisms in the endothelium, vascular smooth muscle (VSM and extracellular matrix cause alterations in vascular tone and blood vessel remodeling and may lead to persistent increases in vascular resistance and hypertension (HTN. In VSM, activation of surface receptors by vasoconstrictor stimuli causes an increase in intracellular free Ca2+ concentration ([Ca2+]i, which forms a complex with calmodulin, activates myosin light chain (MLC kinase and leads to MLC phosphorylation, actin-myosin interaction and VSM contraction. Vasoconstrictor agonists could also increase the production of diacylglycerol which activates protein kinase C (PKC. PKC is a family of Ca2+-dependent and Ca2+-independent isozymes that have different distributions in various blood vessels, and undergo translocation from the cytosol to the plasma membrane, cytoskeleton or the nucleus during cell activation. In VSM, PKC translocation to the cell surface may trigger a cascade of biochemical events leading to activation of mitogen-activated protein kinase (MAPK and MAPK kinase (MEK, a pathway that ultimately increases the myofilament force sensitivity to [Ca2+]i, and enhances actin-myosin interaction and VSM contraction. PKC translocation to the nucleus may induce transactivation of various genes and promote VSM growth and proliferation. PKC could also affect endothelium-derived relaxing and contracting factors as well as matrix metalloproteinases (MMPs in the extracellular matrix further affecting vascular reactivity and remodeling. In addition to vasoactive factors, reactive oxygen species, inflammatory cytokines and other metabolic factors could affect PKC activity. Increased PKC expression and activity have been observed in vascular disease and in certain forms of experimental and human HTN. Targeting of vascular PKC using PKC inhibitors may function in

  8. Vascular regulation of glioma stem-like cells: a balancing act.

    Science.gov (United States)

    Brooks, Lucy J; Parrinello, Simona

    2017-12-01

    Glioblastoma (GBM) are aggressive and therapy-resistant brain tumours driven by glioma stem-like cells (GSCs). GSC behaviour is controlled by the microenvironment, or niche, in which the cells reside. It is well-established that the vasculature is a key component of the GSC niche, which drives maintenance in the tumour bulk and invasion at the margin. Emerging evidence now indicates that the specific properties of the vasculature within these two regions impose different functional states on resident GSCs, generating distinct subpopulations. Here, we review these recent findings, focusing on the mechanisms that underlie GSC/vascular communication. We further discuss how plasticity enables GSCs to respond to vascular changes by interconverting bidirectionally between states, and address the therapeutic implications of this dynamic response. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  9. Regulation of Hyaluronan Synthesis in Vascular Diseases and Diabetes

    Directory of Open Access Journals (Sweden)

    Paola Moretto

    2015-01-01

    Full Text Available Cell microenvironment has a critical role determining cell fate and modulating cell responses to injuries. Hyaluronan (HA is a ubiquitous extracellular matrix glycosaminoglycan that can be considered a signaling molecule. In fact, interacting with several cell surface receptors can deeply shape cell behavior. In vascular biology, HA triggers smooth muscle cells (SMCs dedifferentiation which contributes to vessel wall thickening. Furthermore, HA is able to modulate inflammation by altering the adhesive properties of endothelial cells. In hyperglycemic conditions, HA accumulates in vessels and can contribute to the diabetic complications at micro- and macrovasculature. Due to the pivotal role in favoring atherogenesis and neointima formation after injuries, HA could be a new target for cardiovascular pathologies. This review will focus on the recent findings regarding the regulation of HA synthesis in human vascular SMCs. In particular, the effects of the intracellular HA substrates availability, adenosine monophosphate-activated protein kinase (AMPK, and protein O-GlcNAcylation on the main HA synthetic enzyme (i.e., HAS2 will be discussed.

  10. Fluid shear promotes chondrosarcoma cell invasion by activating matrix metalloproteinase 12 via IGF-2 and VEGF signaling pathways

    Science.gov (United States)

    Wang, P; Chen, S-H; Hung, W-C; Paul, C; Zhu, F; Guan, P-P; Huso, DL; Kontrogianni-Konstantopoulos, A; Konstantopoulos, K

    2015-01-01

    Interstitial fluid flow in and around the tumor tissue is a physiologically relevant mechanical signal that regulates intracellular signaling pathways throughout the tumor. Yet, the effects of interstitial flow and associated fluid shear stress on the tumor cell function have been largely overlooked. Using in vitro bioengineering models in conjunction with molecular cell biology tools, we found that fluid shear (2 dyn/cm2) markedly upregulates matrix metalloproteinase 12 (MMP-12) expression and its activity in human chondrosarcoma cells. MMP-12 expression is induced in human chondrocytes during malignant transformation. However, the signaling pathway regulating MMP-12 expression and its potential role in human chondrosarcoma cell invasion and metastasis have yet to be delineated. We discovered that fluid shear stress induces the synthesis of insulin growth factor-2 (IGF-2) and vascular endothelial growth factor (VEGF) B and D, which in turn transactivate MMP-12 via PI3-K, p38 and JNK signaling pathways. IGF-2-, VEGF-B- or VEGF-D-stimulated chondrosarcoma cells display markedly higher migratory and invasive potentials in vitro, which are blocked by inhibiting MMP-12, PI3-K, p38 or JNK activity. Moreover, recombinant human MMP-12 or MMP-12 overexpression can potentiate chondrosarcoma cell invasion in vitro and the lung colonization in vivo. By reconstructing and delineating the signaling pathway regulating MMP-12 activation, potential therapeutic strategies that interfere with chondrosarcoma cell invasion may be identified. PMID:25435370

  11. Vascular endothelial growth factor and its relationship with the dental pulp.

    Science.gov (United States)

    Grando Mattuella, Leticia; Westphalen Bento, Leticia; de Figueiredo, José Antonio Poli; Nör, Jacques Eduardo; de Araujo, Fernando Borba; Fossati, Anna Christina Medeiros

    2007-05-01

    The dental pulp is a loose connective tissue located within rigid dentinal walls. Therefore, when subjected to a stimulus, the pulpal tissue has little expansion capacity. The defense mechanisms of this tissue include the formation of tertiary dentin as well as the production of signaling molecules that help in the repair. The dentin matrix is rich in growth factors (GFs) that, when diluted and diffused into the pulp tissue, aid the healing process of the dentinopulpar complex. The angiogenic GFs participate in this event. Vascular endothelial growth factor (VEGF), a potent mitogen for endothelial cells, promotes endothelial cell survival and angiogenesis. Among its receptors, VEGFR-2 seems to be the most intimately associated with mitogenic activities, cell migration, vascular permeability, and survival of endothelial cells. This literature review addresses the cell-signaling process that occurs in response to a pulp stimulus up to its transduction in the target cell, describing the VEGF, as well as its characteristics and receptors. The reported studies have correlated the expression of VEGF and its potential functions that may have an impact on several dental specialties, thus indicating that further clinical investigations should be conducted in order to translate the results obtained until this moment primarily in laboratory experiments.

  12. Gastrin-releasing peptide induces monocyte adhesion to vascular endothelium by upregulating endothelial adhesion molecules

    International Nuclear Information System (INIS)

    Kim, Mi-Kyoung; Park, Hyun-Joo; Kim, Yeon; Kim, Hyung Joon; Bae, Soo-Kyung; Bae, Moon-Kyoung

    2017-01-01

    Gastrin-releasing peptide (GRP) is a neuropeptide that plays roles in various pathophysiological conditions including inflammatory diseases in peripheral tissues; however, little is known about whether GRP can directly regulate endothelial inflammatory processes. In this study, we showed that GRP promotes the adhesion of leukocytes to human umbilical vein endothelial cells (HUVECs) and the aortic endothelium. GRP increased the expression of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) by activating nuclear factor-κB (NF-κB) in endothelial cells. In addition, GRP activated extracellular signal-regulated kinase 1/2 (ERK1/2), p38MAPK, and AKT, and the inhibition of these signaling pathways significantly reduced GRP-induced monocyte adhesion to the endothelium. Overall, our results suggested that GRP may cause endothelial dysfunction, which could be of particular relevance in the development of vascular inflammatory disorders. - Highlights: • GRP induces adhesion of monocytes to vascular endothelium. • GRP increases the expression of endothelial adhesion molecules through the activation of NF-κB. • ERK1/2, p38MAPK, and Akt pathways are involved in the GRP-induced leukocyte adhesiveness to endothelium.

  13. Selective Expression of an Endogenous Inhibitor of FAK Regulates Proliferation and Migration of Vascular Smooth Muscle Cells

    Science.gov (United States)

    Taylor, Joan M.; Mack, Christopher P.; Nolan, Kate; Regan, Christopher P.; Owens, Gary K.; Parsons, J. Thomas

    2001-01-01

    Extracellular matrix signaling via integrin receptors is important for smooth muscle cell (SMC) differentiation during vasculogenesis and for phenotypic modulation of SMCs during atherosclerosis. We previously reported that the noncatalytic carboxyl-terminal protein binding domain of focal adhesion kinase (FAK) is expressed as a separate protein termed FAK-related nonkinase (FRNK) and that ectopic expression of FRNK can attenuate FAK activity and integrin-dependent signaling (A. Richardson and J. T. Parsons, Nature 380:538–540, 1996). Herein we report that in contrast to FAK, which is expressed ubiquitously, FRNK is expressed selectively in SMCs, with particularly high levels observed in conduit blood vessels. FRNK expression was low during embryonic development, was significantly upregulated in the postnatal period, and returned to low but detectable levels in adult tissues. FRNK expression was also dramatically upregulated following balloon-induced carotid artery injury. In cultured rat aortic smooth muscle cells, overexpression of FRNK attenuated platelet-derived growth factor (PDGF)-BB-induced migration and also dramatically inhibited [3H]thymidine incorporation upon stimulation with PDGF-BB or 10% serum. These effects were concomitant with a reduction in SMC proliferation. Taken together, these data indicate that FRNK acts as an endogenous inhibitor of FAK signaling in SMCs. Furthermore, increased FRNK expression following vascular injury or during development may alter the SMC phenotype by negatively regulating proliferative and migratory signals. PMID:11238893

  14. Experimental study on effect of arsenic trioxide on vascular smooth muscle cells

    International Nuclear Information System (INIS)

    Lu Qin; An Yanli; Niu Huanzhang; Teng Gaojun; Wang Zihao; Zhang Dongsheng; Fang Juanjuan

    2007-01-01

    Objective: To investigate the effect of arsenic trioxide (As 2 O 3 ) nanoparticles on rabbit vascular smooth muscle cells in vitro in comparison with normal form As 2 O 3 . Methods: The rabbit vascular smooth muscle cells were cultured in vitro. Nano and normal forms of As 2 O 3 with drug concentrations of 3 μmol/L were added into the cells. Cell proliferation curve was drawn according to the light absorption values of MTT test. Flow cytometry was applied to observe the apoptosis. DNA was extracted and underwent electrophoresis. Results: Cell proliferation treated with the 3 μmol/L concentration of As 2 O 3 was inhibited. Cell growth was inhibited markedly with increased treatment time, and the inhibition effect of nano drug form seemed stronger than that of normal form. MTT light absorption values of cells treated at 24, 48 and 72 h showed statistically significant difference (H=10.934, 15.039, 15.539, P 2 O 3 , normal drug form of As 2 O 3 and control group of cells without As 2 O 3 were 44.97%, 58.54%, 74.02% respectively. The early apoptosis rates were 16.89%, 11.27%, 11.20%, late apoptosis rates were 26.56%, 23.60%, 12.46%, and necrosis rates were 11.58%, 6.59%, 2.32% respectively. Agarose gel electrophoresis showed 'ladder' strand of DNA, with more strands and obscurity for nano drug form treated cells. Conclusion: Arsenic trioxide may inhibit the growth of rabbit vascular smooth muscle cells. The nano drug form showed stronger inhibition effect than that of the normal drug form. (authors)

  15. Epidermal growth factor-mediated effects on equine vascular smooth muscle cells

    International Nuclear Information System (INIS)

    Grosenbaugh, D.A.; Amoss, M.S.; Hood, D.M.; Morgan, S.J.; Williams, J.D.

    1988-01-01

    Epidermal growth factor (EGF) receptor binding kinetics and EGF-mediated stimulation of DNA synthesis and cellular proliferation were studied in cultured vascular smooth muscle cells (VSMC) from the equine thoracic aorta. Binding studies, using murine 125 I-labeled EGF, indicate the presence of a single class of high-affinity binding sites, with an estimated maximal binding capacity of 5,800 sites/cells. EGF stimulated [ 3 H]thymidine uptake in confluent quiescent monolayers in a dose-dependent fashion, half-maximal stimulation occurring at 7.5 x 10 -11 M. Likewise, EGF-mediated cellular proliferation was dose dependent under reduced serum concentrations. Equine VSMC contain specific receptors for EGF, and EGF can stimulate DNA synthesis and proliferation in these cultured cells, which suggests that EGF may participate in the proliferative changes observed in equine distal digital peripheral vascular disease

  16. Nano- and microstructured materials for in vitro studies of the physiology of vascular cells

    OpenAIRE

    Alexandra M. Greiner; Adria Sales; Hao Chen; Sarah A. Biela; Dieter Kaufmann; Ralf Kemkemer

    2016-01-01

    The extracellular environment of vascular cells in vivo is complex in its chemical composition, physical properties, and architecture. Consequently, it has been a great challenge to study vascular cell responses in vitro, either to understand their interaction with their native environment or to investigate their interaction with artificial structures such as implant surfaces. New procedures and techniques from materials science to fabricate bio-scaffolds and surfaces have enabled novel studi...

  17. RhoA-Rho kinase and platelet-activating factor stimulation of ovine foetal pulmonary vascular smooth muscle cell proliferation.

    Science.gov (United States)

    Renteria, L S; Austin, M; Lazaro, M; Andrews, M A; Lustina, J; Raj, J U; Ibe, B O

    2013-10-01

    Platelet-activating factor (PAF) is produced by pulmonary vascular smooth muscle cells (PVSMC). We studied effects of Rho kinase on PAF stimulation of PVSMC proliferation in an attempt to understand the role of RhoA/Rho kinase on PAF-induced ovine foetal pulmonary vascular remodelling. Our hypothesis is that PAF acts through Rho kinase, as one of its downstream signals, to induce arterial (SMC-PA) and venous (SMC-PV) cell proliferation in the hypoxic lung environment of the foetus, in utero. Rho kinase and MAPK effects on PAF receptor (PAFR)-mediated cell population expansion, and PAFR expression, were studied by DNA synthesis, western blot analysis and immunocytochemistry. Effects of constructs T19N and G14V on PAF-induced cell proliferation were also investigated. Hypoxia increased PVSMC proliferation and Rho kinase inhibitors, Y-27632 and Fasudil (HA-1077) as well as MAPK inhibitors PD 98059 and SB 203580 attenuated PAF stimulation of cell proliferation. RhoA T19N and G14V stimulated cell proliferation, but co-incubation with PAF did not affect proliferative effects of the constructs. PAFR protein expression was significantly downregulated in both cell types by both Y-27632 and HA-1077, with comparable profiles. Also, cells treated with Y-27632 had less PAF receptor fluorescence with significant disruption of cell morphology. Our results show that Rho kinase non-specifically modulated PAFR-mediated responses by a translational modification of PAFR protein, and suggest that, in vivo, activation of Rho kinase by PAF may be a further pathway to sustain PAFR-mediated PVSMC proliferation. © 2013 John Wiley & Sons Ltd.

  18. Role of Cell-Cell bond for the viability and the function of vascular smooth muscle cells

    Directory of Open Access Journals (Sweden)

    M. Mura

    2010-01-01

    Full Text Available Vascular smooth muscle cell (VSMC viability and homeostasis is regulated by cell-matrix and cell-cell contact: disruption of these interactions are responsible of a switch from a mature to a high proliferative phenotype. VSMCs migration, rate of growth and apoptosis, and the extent of their extracellular matrix (ECM deposition can be also modulated by proatherogenic peptides. Among them, ATII induces the transactivation of IGF I R, which, together with the binding protein IGFBP3, represents a determinant of cell survival, growth and proliferation. Aim of our in vitro study was to verify the role of elective cell-cell bond in moulating the response to ATII. Thus, we evaluated viability, proliferation, IGFIR, IGFBP3 expression and the long term survival and production of ECM in a provisional tissue. A7r5 cell-line was used in adherent cultures or incubated in agarose-coated culture plates to inhibit cell-matrix interactions. Cells, treated or not with ATII 100 nM, were evaluated for apoptosis rate, cell cycle, IGFIR and IGFBP3 protei expression. Fibrin provisional tissue was developed polymerizing a fibrin solution. cantaining A7r5 cells with thrombin. Histological stainings for ECM components were performed on sections of prvisional tissue. An exclusive cell-cell contact resulted to monolayer cell cultures. ATII did not affect the cell survival in both culture conditions, but promoted a 10% decrease in "S" phase and an increases IGFIR expression only in adherent cells. while suspended cell aggregates were resistant to ATII administration; IGFBP3 was reduced both in ATII treated adherent cells and in floating clustered cells, irrespective of the treatmentn. VSMC conditioning in agarose-coated plates before seeding in fibrin provisional matrix reduced, but not abolished, the cell ability to colonize the clot and to produce ECM. This study demonstrates that the elective cell-cell contact induces a quiescent status in cells lacking of cell

  19. Arterial grafts exhibiting unprecedented cellular infiltration and remodeling in vivo: the role of cells in the vascular wall.

    Science.gov (United States)

    Row, Sindhu; Peng, Haofan; Schlaich, Evan M; Koenigsknecht, Carmon; Andreadis, Stelios T; Swartz, Daniel D

    2015-05-01

    To engineer and implant vascular grafts in the arterial circulation of a pre-clinical animal model and assess the role of donor medial cells in graft remodeling and function. Vascular grafts were engineered using Small Intestinal Submucosa (SIS)-fibrin hybrid scaffold and implanted interpositionally into the arterial circulation of an ovine model. We sought to demonstrate implantability of SIS-Fibrin based grafts; examine the remodeling; and determine whether the presence of vascular cells in the medial wall was necessary for cellular infiltration from the host and successful remodeling of the implants. We observed no occlusions or anastomotic complications in 18 animals that received these grafts. Notably, the grafts exhibited unprecedented levels of host cell infiltration that was not limited to the anastomotic sites but occurred through the lumen as well as the extramural side, leading to uniform cell distribution. Incoming cells remodeled the extracellular matrix and matured into functional smooth muscle cells as evidenced by expression of myogenic markers and development of vascular reactivity. Interestingly, tracking the donor cells revealed that their presence was beneficial but not necessary for successful grafting. Indeed, the proliferation rate and number of donor cells decreased over time as the vascular wall was dominated by host cells leading to significant remodeling and development of contractile function. These results demonstrate that SIS-Fibrin grafts can be successfully implanted into the arterial circulation of a clinically relevant animal model, improve our understanding of vascular graft remodeling and raise the possibility of engineering mural cell-free arterial grafts. Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. Measuring vascular reactivity with resting-state blood oxygenation level-dependent (BOLD) signal fluctuations: A potential alternative to the breath-holding challenge?

    Science.gov (United States)

    Jahanian, Hesamoddin; Christen, Thomas; Moseley, Michael E; Pajewski, Nicholas M; Wright, Clinton B; Tamura, Manjula K; Zaharchuk, Greg

    2017-07-01

    Measurement of the ability of blood vessels to dilate and constrict, known as vascular reactivity, is often performed with breath-holding tasks that transiently raise arterial blood carbon dioxide (P a CO 2 ) levels. However, following the proper commands for a breath-holding experiment may be difficult or impossible for many patients. In this study, we evaluated two approaches for obtaining vascular reactivity information using blood oxygenation level-dependent signal fluctuations obtained from resting-state functional magnetic resonance imaging data: physiological fluctuation regression and coefficient of variation of the resting-state functional magnetic resonance imaging signal. We studied a cohort of 28 older adults (69 ± 7 years) and found that six of them (21%) could not perform the breath-holding protocol, based on an objective comparison with an idealized respiratory waveform. In the subjects that could comply, we found a strong linear correlation between data extracted from spontaneous resting-state functional magnetic resonance imaging signal fluctuations and the blood oxygenation level-dependent percentage signal change during breath-holding challenge ( R 2  = 0.57 and 0.61 for resting-state physiological fluctuation regression and resting-state coefficient of variation methods, respectively). This technique may eliminate the need for subject cooperation, thus allowing the evaluation of vascular reactivity in a wider range of clinical and research conditions in which it may otherwise be impractical.

  1. Improvement of cell infiltration in electrospun polycaprolactone scaffolds for the construction of vascular grafts.

    Science.gov (United States)

    Wang, Kai; Zhu, Meifeng; Li, Ting; Zheng, Wenting; Li, Li; Xu, Mian; Zhao, Qiang; Kong, Deling; Wang, Lianyong

    2014-08-01

    The less-than-ideal cell infiltration resulting from inherently small pore size limits the application of electrospinning scaffold in tissue engineering and regeneration medicine. The present study aims to develop a porogenic method which can significantly increase pore size in electrospinning scaffold and enhance cell migration. With this method, composite scaffolds consisting of poly(epsilon-caprolactone) (PCL) fibers and poly(ethylene oxide) (PEO) microparticles were prepared by simultaneously electrospinning and electrospraying. Removal of the PEO microparticles from the composites generated large pores. In vitro culture of NIH3T3 cells and in vivo subcutaneous implantation both demonstrated that the porogenic scaffolds markedly facilitated cell infiltration. With the same technique, vascular grafts with alternative dense and loose layers were prepared by turning on or off electrospraying PEO. SEM showed that there was no a clear delamination between the loose and dense layers. The mechanical strength and burst pressure of these vascular grafts could meet the requirements of vascular implantation. In conclusion, electrospinning PCL fibers with electrospraying PEO microparticles may be an effective and controllable method to increase pore size in electrospinning scaffold and provides a useful tool for the fabrication of vascular grafts that meets the need of blood vessel replacement.

  2. RNA interference-mediated silencing of speckle-type POZ protein promotes apoptosis of renal cell cancer cells

    Directory of Open Access Journals (Sweden)

    Liu X

    2016-04-01

    Full Text Available Xiaoxia Liu, Guiling Sun, Xiuju Sun Department of Nephrology, Affiliated Hospital of Weifang Medical University, Weifang, People’s Republic of China Abstract: This study aimed to investigate the effects of silencing the speckle-type POZ protein (SPOP gene on renal cell cancer (RCC cells and to explore its possible mechanism. The A498 and ACHN RCC cells were transfected with small interference RNA (siRNA-SPOP by lipofection methods. The silencing efficiency was monitored by quantitative real-time polymerase chain reaction and Western blot. The effects of SPOP silencing on cell apoptosis, cell viability, colony formation ability, cell migration ability, and chemosensitivity to Sorafenib were assessed by flow cytometry, an MTT assay, a colony formation assay, a trans-well migration assay, and a CCK-8 assay, respectively. Its effects on the expression of several cytokines were determined by a protein microarray. Relevant signaling pathways were also analyzed. Compared with the control group, the cell apoptosis rate was significantly higher; the cell viability, the colony formation, and migration ability were significantly decreased in the siRNA-SPOP group. The protein microarray screening showed that the expression of vascular endothelial growth factor receptor, matrix metallopeptidase-9, vascular cell adhesion molecule-1, and stromal cell-derived factor-1 in the siRNA group was significantly decreased and that the expression of granulocyte–macrophage colony-stimulating factor and E-cadherin was significantly increased (P<0.05. The relevant signaling pathways were the integrin-mediated cell surface interactions pathway and extracellular matrix organization signal pathway. SPOP gene silencing induced cell apoptosis, decreased cell viability, colony formation, and migration ability, and elevated the drug sensitivity in the RCC cells. A possible mechanism is that silencing SPOP induces the differential expression of E-cadherin, vascular endothelial

  3. Suppression of complement regulatory protein C1 inhibitor in vascular endothelial activation by inhibiting vascular cell adhesion molecule-1 action

    International Nuclear Information System (INIS)

    Zhang, Haimou; Qin, Gangjian; Liang, Gang; Li, Jinan; Chiu, Isaac; Barrington, Robert A.; Liu, Dongxu

    2007-01-01

    Increased expression of adhesion molecules by activated endothelium is a critical feature of vascular inflammation associated with the several diseases such as endotoxin shock and sepsis/septic shock. Our data demonstrated complement regulatory protein C1 inhibitor (C1INH) prevents endothelial cell injury. We hypothesized that C1INH has the ability of an anti-endothelial activation associated with suppression of expression of adhesion molecule(s). C1INH blocked leukocyte adhesion to endothelial cell monolayer in both static assay and flow conditions. In inflammatory condition, C1INH reduced vascular cell adhesion molecule (VCAM-1) expression associated with its cytoplasmic mRNA destabilization and nuclear transcription level. Studies exploring the underlying mechanism of C1INH-mediated suppression in VCAM-1 expression were related to reduction of NF-κB activation and nuclear translocation in an IκBα-dependent manner. The inhibitory effects were associated with reduction of inhibitor IκB kinase activity and stabilization of the NF-κB inhibitor IκB. These findings indicate a novel role for C1INH in inhibition of vascular endothelial activation. These observations could provide the basis for new therapeutic application of C1INH to target inflammatory processes in different pathologic situations

  4. Upregulation of decorin by FXR in vascular smooth muscle cells

    International Nuclear Information System (INIS)

    He Fengtian; Zhang Qiuhong; Kuruba, Ramalinga; Gao Xiang; Li Jiang; Li Yong; Gong Wei; Jiang, Yu; Xie Wen; Li Song

    2008-01-01

    Decorin is a member of the family of small leucine-rich proteoglycans that are present in blood vessels and synthesized by vascular smooth muscle cells (VSMCs). Decorin plays complex roles in both normal vascular physiology and the pathogenesis of various types of vascular disorders. However, the mechanisms of regulation of decorin expression in vasculature are not clearly understood. Particularly little information is available about a role of nuclear receptors in the regulation of decorin expression. In the present study, we report that activation of vascular FXR by a specific ligand resulted in upregulation of decorin at the levels of both mRNA and protein. FXR appears to induce decorin expression at a transcriptional level because (1) upregulation of decorin mRNA expression was abolished by the treatment of a transcription inhibitor, actinomycin D; and (2) decorin promoter activity was significantly increased by activation of FXR. Functional analysis of human decorin promoter identified an imperfect inverted repeat DNA motif, IR8 (-2313TGGTCAtagtgtcaTGACCT-2294), as a likely FXR-responsive element that is involved in decorin regulation

  5. Hypoxic contraction of cultured pulmonary vascular smooth muscle cells

    International Nuclear Information System (INIS)

    Murray, T.R.; Chen, L.; Marshall, B.E.; Macarak, E.J.

    1990-01-01

    The cellular events involved in generating the hypoxic pulmonary vasoconstriction response are not clearly understood, in part because of the multitude of factors that alter pulmonary vascular tone. The goal of the present studies was to determine if a cell culture preparation containing vascular smooth muscle (VSM) cells could be made to contract when exposed to a hypoxic atmosphere. Cultures containing only fetal bovine pulmonary artery VSM cells were assessed for contractile responses to hypoxic stimuli by two methods. In the first, tension forces generated by cells grown on a flexible growth surface (polymerized polydimethyl siloxane) were manifested as wrinkles and distortions of the surface under the cells. Wrinkling of the surface was noted to progressively increase with time as the culture medium bathing the cells was made hypoxic (PO2 approximately 25 mmHg). The changes were sometimes reversible upon return to normoxic conditions and appeared to be enhanced in cells already exhibiting evidence of some baseline tone. Repeated passage in culture did not diminish the hypoxic response. Evidence for contractile responses to hypoxia was also obtained from measurements of myosin light chain (MLC) phosphorylation. Conversion of MLC to the phosphorylated species is an early step in the activation of smooth muscle contraction. Lowering the PO2 in the culture medium to 59 mmHg caused a 45% increase in the proportion of MLC in the phosphorylated form as determined by two-dimensional gel electrophoresis. Similarly, cultures preincubated for 4 h with 32P and then exposed to normoxia or hypoxia for a 5-min experimental period showed more than twice as much of the label in MLCs of the hypoxic cells

  6. Effects of x-irradiation on growth of vascular smooth muscle cells

    International Nuclear Information System (INIS)

    Dzoga, K.F.; Dimitrievich, G.S.; Sutton, H.G.; Griem, M.L.

    1984-01-01

    Effects of x-irradiation doses ranging from 0-2000 rads on vascular smooth muscle cells were measured. Explant cultures were from the medial layers of aortas from New Zealand rabbits. X-irradiation was delivered to narrow mediastinal port using a 250 kV Maxitron at a rate of 80 rads/min. and a S-C distance of 60 cm. Explantation was done either immediately following radiation or five days later. Two parameters were used to determine post-irradiation growth potential of these cells: number of outgrowing cells per seeded explant and size and number of cells/culture. Results were expressed as fraction of control. Irradiation immediately before explantation reduced number of cells/ explant 10% for 250 rads and over 50% for 500 rads. Doses of 1000 rads and over resulted in reductions of over 70% in number of growing explants and culture size. When five days were allowed to elapse between x-irradiation and explantation the same parameters were not significantly affected for doses of 500 rads or less. Doses of 1000 rads resulted in a reduction in number of cells of 40% and 2000 rads of over 80%. These results suggest the presence of a population of vascular repair cells five days following irradiation treatment. The nature of these cells is discussed

  7. Mobilization of endothelial precursor cells: systemic vascular response to musculoskeletal trauma.

    LENUS (Irish Health Repository)

    Laing, A J

    2012-02-03

    Postnatal vasculogenesis, the process by which vascular committed bone marrow stem cells or endothelial precursor cells (EPC) migrate, differentiate, and incorporate into the nacent endothelium contributing to physiological and pathological neovascularization, has stimulated much interest. Its contribution to tumor nonvascularization, wound healing, and revascularization associated with skeletal and cardiac muscles ischaemia is established. We evaluated the mobilization of EPCs in response to musculoskeletal trauma. Blood from patients (n = 15) following AO type 42a1 closed diaphyseal tibial fractures was analyzed for CD34 and AC133 cell surface marker expression. Immunomagnetically enriched CD34+ mononuclear cell (MNC(CD34+)) populations were cultured and examined for phenotypic and functional vascular endothelial differentiation. Circulating MNC(CD34+) levels increased sevenfold by day 3 postinjury. Circulating MNC(AC133+) increased 2.5-fold. Enriched MNC(CD34+) populations from day 3 samples in culture exhibited cell cluster formation with sprouting spindles. These cells bound UEA-1 and incorporated fluorescent DiI-Ac-LDL intracellularily. Our findings suggest a systemic provascular response is initiated in response to musculoskeletal trauma. Its therapeutic manipulation may have implications for the potential enhancement of fracture healing.

  8. RhoA–Rho kinase and Platelet Activating Factor Stimulation of Ovine Fetal Pulmonary Vascular Smooth Muscle Cell Proliferation

    Science.gov (United States)

    Renteria, Lissette S.; Austin, Monique; Lazaro, Mariecon; Andrews, Mari Ashley; Lustina, Jennessee; Raj, J. Usha; Ibe, Basil O.

    2013-01-01

    Objectives Platelet Activating Factor (PAF) is produced by pulmonary vascular smooth muscle Cells (PVSMC). We studied effect of Rho kinase on PAF stimulation of PVSMC proliferation in an attempt to understand a role for RhoA/Rho kinase on PAF-induced ovine fetal pulmonary vascular remodeling. Our hypothesis is that PAF acts through Rho kinase, as one of its downstream signaling, to induce arterial (SMC-PA) and venous (SMC-PV) growth in the hypoxic lung environment of the fetus in utero. Materials and methods Rho kinase and MAPK effects on PAF receptor (PAFR)-mediated cell growth and PAFR expression were studied by DNA synthesis, Western and immunocytochemistry. Effects of constructs T19N and G14V on PAF-induced cell proliferation was also studied. Results Hypoxia increased PVSMC proliferation and the Rho kinase inhibitors, Y-27632 and Fasudil (HA-1077) as well as MAPK inhibitors PD 98059 and SB 203580 attenuated PAF stimulation of cell proliferation. RhoA T19N and G14V stimulated cell proliferation, but co-incubation with PAF did not affect proliferative effects of the constructs. PAFR protein expression was significantly down-regulated in both cell types by both Y-27632 and HA-1077 with comparable profiles. Also cells treated with Y-27632 showed less PAF receptor fluorescence with significant disruption of the cell morphology. Conclusions Our results show that Rho kinase nonspecifically modulates PAFR-mediated responses via a translational modification of PAFR protein and suggest that, in vivo, activation of Rho kinase by PAF may be one other pathway to sustain PAFR-mediated PVSMC growth. PMID:24033386

  9. E-Cigarette Aerosol Exposure Induces Reactive Oxygen Species, DNA Damage, and Cell Death in Vascular Endothelial Cells.

    Science.gov (United States)

    Anderson, Chastain; Majeste, Andrew; Hanus, Jakub; Wang, Shusheng

    2016-12-01

    Cigarette smoking remains one of the leading causes of preventable death worldwide. Vascular cell death and dysfunction is a central or exacerbating component in the majority of cigarette smoking related pathologies. The recent development of the electronic nicotine delivery systems known as e-cigarettes provides an alternative to conventional cigarette smoking; however, the potential vascular health risks of e-cigarette use remain unclear. This study evaluates the effects of e-cigarette aerosol extract (EAE) and conventional cigarette smoke extract (CSE) on human umbilical vein endothelial cells (HUVECs). A laboratory apparatus was designed to produce extracts from e-cigarettes and conventional cigarettes according to established protocols for cigarette smoking. EAE or conventional CSE was applied to human vascular endothelial cells for 4-72 h, dependent on the assay. Treated cells were assayed for reactive oxygen species, DNA damage, cell viability, and markers of programmed cell death pathways. Additionally, the anti-oxidants α-tocopherol and n-acetyl-l-cysteine were used to attempt to rescue e-cigarette induced cell death. Our results indicate that e-cigarette aerosol is capable of inducing reactive oxygen species, causing DNA damage, and significantly reducing cell viability in a concentration dependent fashion. Immunofluorescent and flow cytometry analysis indicate that both the apoptosis and programmed necrosis pathways are triggered by e-cigarette aerosol treatment. Additionally, anti-oxidant treatment provides a partial rescue of the induced cell death, indicating that reactive oxygen species play a causal role in e-cigarette induced cytotoxicity. © The Author 2016. Published by Oxford University Press on behalf of the Society of Toxicology. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  10. Resveratrol prevents angiotensin II-induced hypertrophy of vascular smooth muscle cells through the transactivation of growth factor receptors.

    Science.gov (United States)

    Hossain, Ekhtear; Anand-Srivastava, Madhu B

    2017-08-01

    We previously showed that augmented levels of endogenous angiotensin II (AngII) contribute to vascular smooth muscle cell (VSMC) hypertrophy through the transactivation of growth factor receptors in spontaneously hypertensive rats. Resveratrol (RV), a polyphenolic component of red wine, has also been shown to attenuate AngII-evoked VSMC hypertrophy; however, the molecular mechanism mediating this response is obscure. The present study was therefore undertaken to examine whether RV could prevent AngII-induced VSMC hypertrophy through the transactivation of growth factor receptor and associated signaling pathways. AngII treatment of VSMC enhanced the protein synthesis that was attenuated towards control levels by RV pretreatment as well as by the inhibitors of NADPH oxidase, c-Src, and growth factor receptors. Furthermore, RV pretreatment also inhibited enhanced levels of superoxide anion, NADPH oxidase activity, increased expression of NADPH oxidase subunits, and phosphorylation of c-Src, EGF-R, PDGE-R, ERK1/2, and AKT1/2. In conclusion, these results indicate that RV attenuates AngII-induced VSMC hypertrophy through the inhibition of enhanced oxidative stress and activation of c-Src, growth factor receptors, and MAPK/AKT signaling. We suggest that RV could be used as a therapeutic agent in the treatment of vascular complications associated with hypertension and hypertrophy.

  11. Functions of Müller cell-derived vascular endothelial growthfactor in diabetic retinopathy

    Institute of Scientific and Technical Information of China (English)

    2015-01-01

    Müller cells are macroglia and play many essentialroles as supporting cells in the retina. To respond topathological changes in diabetic retinopathy (DR), amajor complication in the eye of diabetic patients,retinal Müller glia produce a high level of vascularendothelial growth factor (VEGF or VEGF-A). As VEGFis expressed by multiple retinal cell-types and Müllerglia comprise only a small portion of cells in the retina,it has been a great challenge to reveal the function ofVEGF or other globally expressed proteins produced byMüller cells. With the development of conditional genetargeting tools, it is now possible to dissect the functionof Müller cell-derived VEGF in vivo . By using conditionalgene targeting approach, we demonstrate that Müllerglia are a major source of retinal VEGF in diabetic miceand Müller cell-derived VEGF plays a significant role inthe alteration of protein expression and peroxynitration,which leads to retinal inflammation, neovascularization,vascular leakage, and vascular lesion, key pathologicalchanges in DR. Therefore, Müller glia are a potentialcellular target for the treatment of DR, a leading causeof blindness.

  12. Molecular biology of breast cancer metastasis Molecular expression of vascular markers by aggressive breast cancer cells

    International Nuclear Information System (INIS)

    Hendrix, Mary JC; Seftor, Elisabeth A; Kirschmann, Dawn A; Seftor, Richard EB

    2000-01-01

    During embryogenesis, the formation of primary vascular networks occurs via the processes of vasculogenesis and angiogenesis. In uveal melanoma, vasculogenic mimicry describes the 'embryonic-like' ability of aggressive, but not nonaggressive, tumor cells to form networks surrounding spheroids of tumor cells in three-dimensional culture; these recapitulate the patterned networks seen in patients' aggressive tumors and correlates with poor prognosis. The molecular profile of these aggressive tumor cells suggests that they have a deregulated genotype, capable of expressing vascular phenotypes. Similarly, the embryonic-like phenotype expressed by the aggressive human breast cancer cells is associated with their ability to express a variety of vascular markers. These studies may offer new insights for consideration in breast cancer diagnosis and therapeutic intervention strategies

  13. Vascular wall-resident CD44+ multipotent stem cells give rise to pericytes and smooth muscle cells and contribute to new vessel maturation.

    Directory of Open Access Journals (Sweden)

    Diana Klein

    Full Text Available Here, we identify CD44(+CD90(+CD73(+CD34(-CD45(- cells within the adult human arterial adventitia with properties of multipotency which were named vascular wall-resident multipotent stem cells (VW-MPSCs. VW-MPSCs exhibit typical mesenchymal stem cell characteristics including cell surface markers in immunostaining and flow cytometric analyses, and differentiation into adipocytes, chondrocytes and osteocytes under culture conditions. Particularly, TGFß1 stimulation up-regulates smooth muscle cell markers in VW-MPSCs. Using fluorescent cell labelling and co-localisation studies we show that VW-MPSCs differentiate to pericytes/smooth muscle cells which cover the wall of newly formed endothelial capillary-like structures in vitro. Co-implantation of EGFP-labelled VW-MPSCs and human umbilical vein endothelial cells into SCID mice subcutaneously via Matrigel results in new vessels formation which were covered by pericyte- or smooth muscle-like cells generated from implanted VW-MPSCs. Our results suggest that VW-MPSCs are of relevance for vascular morphogenesis, repair and self-renewal of vascular wall cells and for local capacity of neovascularization in disease processes.

  14. Slow and sustained nitric oxide releasing compounds inhibit multipotent vascular stem cell proliferation and differentiation without causing cell death

    International Nuclear Information System (INIS)

    Curtis, Brandon M.; Leix, Kyle Alexander; Ji, Yajing; Glaves, Richard Samuel Elliot; Ash, David E.; Mohanty, Dillip K.

    2014-01-01

    Highlights: • Multipotent vascular stem cells (MVSCs) proliferate and differentiate. • Nitric oxide inhibits proliferation of MVSCs. • Nitric oxide inhibits MVSC differentiation to mesenchymal-like stem cells (MSCs). • Smooth muscle cells (SMCs) neither de-differentiate nor proliferate. - Abstract: Atherosclerosis is the leading cause of cerebral and myocardial infarction. It is believed that neointimal growth common in the later stages of atherosclerosis is a result of vascular smooth muscle cell (SMC) de-differentiation in response to endothelial injury. However, the claims of the SMC de-differentiation theory have not been substantiated by monitoring the fate of mature SMCs in response to such injuries. A recent study suggests that atherosclerosis is a consequence of multipotent vascular stem cell (MVSC) differentiation. Nitric oxide (NO) is a well-known mediator against atherosclerosis, in part because of its inhibitory effect on SMC proliferation. Using three different NO-donors, we have investigated the effects of NO on MVSC proliferation. Results indicate that NO inhibits MVSC proliferation in a concentration dependent manner. A slow and sustained delivery of NO proved to inhibit proliferation without causing cell death. On the other hand, larger, single-burst NO concentrations, inhibits proliferation, with concurrent significant cell death. Furthermore, our results indicate that endogenously produced NO inhibits MVSC differentiation to mesenchymal-like stem cells (MSCs) and subsequently to SMC as well

  15. Slow and sustained nitric oxide releasing compounds inhibit multipotent vascular stem cell proliferation and differentiation without causing cell death

    Energy Technology Data Exchange (ETDEWEB)

    Curtis, Brandon M.; Leix, Kyle Alexander [Department of Chemistry, Central Michigan University, Mount Pleasant, MI 48859 (United States); Ji, Yajing [Department of Biomedical Science and Medicine, Michigan State University, East Lansing, MI 48824 (United States); Glaves, Richard Samuel Elliot [Department of Biology, Central Michigan University, Mount Pleasant, MI 48859 (United States); Ash, David E. [Department of Chemistry, Central Michigan University, Mount Pleasant, MI 48859 (United States); Mohanty, Dillip K., E-mail: Mohan1dk@cmich.edu [Department of Chemistry, Central Michigan University, Mount Pleasant, MI 48859 (United States)

    2014-07-18

    Highlights: • Multipotent vascular stem cells (MVSCs) proliferate and differentiate. • Nitric oxide inhibits proliferation of MVSCs. • Nitric oxide inhibits MVSC differentiation to mesenchymal-like stem cells (MSCs). • Smooth muscle cells (SMCs) neither de-differentiate nor proliferate. - Abstract: Atherosclerosis is the leading cause of cerebral and myocardial infarction. It is believed that neointimal growth common in the later stages of atherosclerosis is a result of vascular smooth muscle cell (SMC) de-differentiation in response to endothelial injury. However, the claims of the SMC de-differentiation theory have not been substantiated by monitoring the fate of mature SMCs in response to such injuries. A recent study suggests that atherosclerosis is a consequence of multipotent vascular stem cell (MVSC) differentiation. Nitric oxide (NO) is a well-known mediator against atherosclerosis, in part because of its inhibitory effect on SMC proliferation. Using three different NO-donors, we have investigated the effects of NO on MVSC proliferation. Results indicate that NO inhibits MVSC proliferation in a concentration dependent manner. A slow and sustained delivery of NO proved to inhibit proliferation without causing cell death. On the other hand, larger, single-burst NO concentrations, inhibits proliferation, with concurrent significant cell death. Furthermore, our results indicate that endogenously produced NO inhibits MVSC differentiation to mesenchymal-like stem cells (MSCs) and subsequently to SMC as well.

  16. Cell-Cell Contact Area Affects Notch Signaling and Notch-Dependent Patterning.

    Science.gov (United States)

    Shaya, Oren; Binshtok, Udi; Hersch, Micha; Rivkin, Dmitri; Weinreb, Sheila; Amir-Zilberstein, Liat; Khamaisi, Bassma; Oppenheim, Olya; Desai, Ravi A; Goodyear, Richard J; Richardson, Guy P; Chen, Christopher S; Sprinzak, David

    2017-03-13

    During development, cells undergo dramatic changes in their morphology. By affecting contact geometry, these morphological changes could influence cellular communication. However, it has remained unclear whether and how signaling depends on contact geometry. This question is particularly relevant for Notch signaling, which coordinates neighboring cell fates through direct cell-cell signaling. Using micropatterning with a receptor trans-endocytosis assay, we show that signaling between pairs of cells correlates with their contact area. This relationship extends across contact diameters ranging from micrometers to tens of micrometers. Mathematical modeling predicts that dependence of signaling on contact area can bias cellular differentiation in Notch-mediated lateral inhibition processes, such that smaller cells are more likely to differentiate into signal-producing cells. Consistent with this prediction, analysis of developing chick inner ear revealed that ligand-producing hair cell precursors have smaller apical footprints than non-hair cells. Together, these results highlight the influence of cell morphology on fate determination processes. Copyright © 2017 Elsevier Inc. All rights reserved.

  17. Cell-derived microparticles in haemostasis and vascular medicine.

    Science.gov (United States)

    Burnier, Laurent; Fontana, Pierre; Kwak, Brenda R; Angelillo-Scherrer, Anne

    2009-03-01

    Considerable interest for cell-derived microparticles has emerged, pointing out their essential role in haemostatic response and their potential as disease markers, but also their implication in a wide range of physiological and pathological processes. They derive from different cell types including platelets - the main source of microparticles - but also from red blood cells, leukocytes and endothelial cells, and they circulate in blood. Despite difficulties encountered in analyzing them and disparities of results obtained with a wide range of methods, microparticle generation processes are now better understood. However, a generally admitted definition of microparticles is currently lacking. For all these reasons we decided to review the literature regarding microparticles in their widest definition, including ectosomes and exosomes, and to focus mainly on their role in haemostasis and vascular medicine.

  18. Activation tagging of the two closely linked genes LEP and VAS independently affects vascular cell number

    DEFF Research Database (Denmark)

    van der Graaff, Eric; Hooykaas, Paul J J; Keller, Beat

    2002-01-01

    report that in addition to this leafy petiole phenotype, the size of the vascular bundles is increased in all aerial organs in let as a result of an increase in the number of xylem, phloem (pro)cambial and pericycle cells. This vascular phenotype is caused by activation tagging of the two genes VASCULAR......-promoting factor. The activation tagging of VAS only resulted in a specific increase in phloem (pro)cambial and pericycle cells. We conclude that activation tagging of LEP and VAS results in additive phenotypes. Insertional mutants for LEP and VAS display wild-type vascular development, indicating the relevance...... of activation tagging for functional analysis of novel genes involved in plant development....

  19. Vascular endothelial growth factors: multitasking functionality in metabolism, health and disease.

    Science.gov (United States)

    Smith, Gina A; Fearnley, Gareth W; Harrison, Michael A; Tomlinson, Darren C; Wheatcroft, Stephen B; Ponnambalam, Sreenivasan

    2015-07-01

    Vascular endothelial growth factors (VEGFs) bind to VEGF receptor tyrosine kinases (VEGFRs). The VEGF and VEGFR gene products regulate diverse regulatory pathways in mammalian development, health and disease. The interaction between a particular VEGF and its cognate VEGFR activates multiple signal transduction pathways which regulate different cellular responses including metabolism, gene expression, proliferation, migration, and survival. The family of VEGF isoforms regulate vascular physiology and promote tissue homeostasis. VEGF dysfunction is implicated in major chronic disease states including atherosclerosis, diabetes, and cancer. More recent studies implicate a strong link between response to VEGF and regulation of vascular metabolism. Understanding how this family of multitasking cytokines regulates cell and animal function has implications for treating many different diseases.

  20. Characterization of vascular endothelial progenitor cells from chicken bone marrow

    Directory of Open Access Journals (Sweden)

    Bai Chunyu

    2012-05-01

    Full Text Available Abstract Background Endothelial progenitor cells (EPC are a type of stem cell used in the treatment of atherosclerosis, vascular injury and regeneration. At present, most of the EPCs studied are from human and mouse, whereas the study of poultry-derived EPCs has rarely been reported. In the present study, chicken bone marrow-derived EPCs were isolated and studied at the cellular level using immunofluorescence and RT-PCR. Results We found that the majority of chicken EPCs were spindle shaped. The growth-curves of chicken EPCs at passages (P 1, -5 and -9 were typically “S”-shaped. The viability of chicken EPCs, before and after cryopreservation was 92.2% and 81.1%, respectively. Thus, cryopreservation had no obvious effects on the viability of chicken EPCs. Dil-ac-LDL and FITC-UAE-1 uptake assays and immunofluorescent detection of the cell surface markers CD34, CD133, VEGFR-2 confirmed that the cells obtained in vitro were EPCs. Observation of endothelial-specific Weibel-Palade bodies using transmission electron microscopy further confirmed that the cells were of endothelial lineage. In addition, chicken EPCs differentiated into endothelial cells and smooth muscle cells upon induction with VEGF and PDGF-BB, respectively, suggesting that the chicken EPCs retained multipotency in vitro. Conclusions These results suggest that chicken EPCs not only have strong self-renewal capacity, but also the potential to differentiate into endothelial and smooth muscle cells. This research provides theoretical basis and experimental evidence for potential therapeutic application of endothelial progenitor cells in the treatment of atherosclerosis, vascular injury and diabetic complications.

  1. NADPH oxidase and lipid raft-associated redox signaling are required for PCB153-induced upregulation of cell adhesion molecules in human brain endothelial cells

    International Nuclear Information System (INIS)

    Eum, Sung Yong; Andras, Ibolya; Hennig, Bernhard; Toborek, Michal

    2009-01-01

    Exposure to persistent organic pollutants, such as polychlorinated biphenyls (PCBs), can lead to chronic inflammation and the development of vascular diseases. Because cell adhesion molecules (CAMs) of the cerebrovascular endothelium regulate infiltration of inflammatory cells into the brain, we have explored the molecular mechanisms by which ortho-substituted polychlorinated biphenyls (PCBs), such as PCB153, can upregulate CAMs in brain endothelial cells. Exposure to PCB153 increased expression of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1), as well as elevated adhesion of leukocytes to brain endothelial cells. These effects were impeded by inhibitors of EGFR, JAKs, or Src activity. In addition, pharmacological inhibition of NADPH oxidase or disruption of lipid rafts by cholesterol depleting agents blocked PCB153-induced phosphorylation of JAK and Src kinases and upregulation of CAMs. In contrast, silencing of caveolin-1 by siRNA interference did not affect upregulation of ICAM-1 and VCAM-1 in brain endothelial cells stimulated by PCB153. Results of the present study indicate that lipid raft-dependent NADPH oxidase/JAK/EGFR signaling mechanisms regulate the expression of CAMs in brain endothelial cells and adhesion of leukocytes to endothelial monolayers. Due to its role in leukocyte infiltration, induction of CAMs may contribute to PCB-induced cerebrovascular disorders and neurotoxic effects in the CNS.

  2. Inhibition of MAPK and PKC pathways by 60Co γ-radiation in cultured vascular smooth muscle cells

    International Nuclear Information System (INIS)

    Jia Guanghong; Ma Yexin; Xiao Jianming

    2002-01-01

    Objective: To investigate the signal transduction pathways inhibited by 60 Co γ-radiation in cultured vascular smooth muscle cells (VSMC). Methods: The cultured VSMC were irradiated with 60 Co γ-radiation of 3.5, 7.0 and 14 Gy respectively. VSMC proliferation was measured by 3 H-TdR incorporation, while PKC, MAPK activities were determined by radioactivity assay. Results: Proliferation of VSMC was inhibited by 7.0, 14 Gy 60 Co γ-irradiation and the activities of PKC, MAPK were decreased significantly. Conclusion: Inhibitory effect of 7.0, 14 Gy 60 Co γ-irradiation on proliferation of VSMC might be resulted from decrease of the activity of PKC, MAPK

  3. Epigenetic regulation of vascular smooth muscle cell function in atherosclerosis.

    Science.gov (United States)

    Findeisen, Hannes M; Kahles, Florian K; Bruemmer, Dennis

    2013-04-01

    Epigenetics involve heritable and acquired changes in gene transcription that occur independently of the DNA sequence. Epigenetic mechanisms constitute a hierarchic upper-level of transcriptional control through complex modifications of chromosomal components and nuclear structures. These modifications include, for example, DNA methylation or post-translational modifications of core histones; they are mediated by various chromatin-modifying enzymes; and ultimately they define the accessibility of a transcriptional complex to its target DNA. Integrating epigenetic mechanisms into the pathophysiologic concept of complex and multifactorial diseases such as atherosclerosis may significantly enhance our understanding of related mechanisms and provide promising therapeutic approaches. Although still in its infancy, intriguing scientific progress has begun to elucidate the role of epigenetic mechanisms in vascular biology, particularly in the control of smooth muscle cell phenotypes. In this review, we will summarize epigenetic pathways in smooth muscle cells, focusing on mechanisms involved in the regulation of vascular remodeling.

  4. Remodeling the Vascular Microenvironment of Glioblastoma with α-Particles.

    Science.gov (United States)

    Behling, Katja; Maguire, William F; Di Gialleonardo, Valentina; Heeb, Lukas E M; Hassan, Iman F; Veach, Darren R; Keshari, Kayvan R; Gutin, Philip H; Scheinberg, David A; McDevitt, Michael R

    2016-11-01

    Tumors escape antiangiogenic therapy by activation of proangiogenic signaling pathways. Bevacizumab is approved for the treatment of recurrent glioblastoma, but patients inevitably develop resistance to this angiogenic inhibitor. We previously investigated targeted α-particle therapy with 225 Ac-E4G10 as an antivascular approach and showed increased survival and tumor control in a high-grade transgenic orthotopic glioblastoma model. Here, we investigated changes in tumor vascular morphology and functionality caused by 225 Ac-E4G10. We investigated remodeling of the tumor microenvironment in transgenic Ntva glioblastoma mice using a therapeutic 7.4-kBq dose of 225 Ac-E4G10. Immunofluorescence and immunohistochemical analyses imaged morphologic changes in the tumor blood-brain barrier microenvironment. Multicolor flow cytometry quantified the endothelial progenitor cell population in the bone marrow. Diffusion-weighted MR imaged functional changes in the tumor vascular network. The mechanism of drug action is a combination of remodeling of the glioblastoma vascular microenvironment, relief of edema, and depletion of regulatory T and endothelial progenitor cells. The primary remodeling event is the reduction of both endothelial and perivascular cell populations. Tumor-associated edema and necrosis were lessened, resulting in increased perfusion and reduced diffusion. Pharmacologic uptake of dasatinib into tumor was enhanced after α-particle therapy. Targeted antivascular α-particle radiation remodels the glioblastoma vascular microenvironment via a multimodal mechanism of action and provides insight into the vascular architecture of platelet-derived growth factor-driven glioblastoma. © 2016 by the Society of Nuclear Medicine and Molecular Imaging, Inc.

  5. Downregulation of B-myb promotes senescence via the ROS-mediated p53/p21 pathway, in vascular endothelial cells.

    Science.gov (United States)

    Zhou, Zhihui; Yin, Yanlin; Chang, Qun; Sun, Guanqun; Lin, Jiahui; Dai, Yalei

    2017-04-01

    To reveal whether B-myb is involved in preventing senescence of vascular endothelial cells, and if so, to identify possible mechanisms for it. C57/BL6 male mice and primary human aortic endothelial cells (HAECs) were used. Bleomycin was applied to induce stress-related premature senescence. B-myb knockdown was achieved using an siRNA technique and cell senescence was assessed using the senescence-associated β-galactosidase (SA-β-gal) assay. Intracellular reactive oxygen species (ROS) production was analysed using an ROS assay kit and cell proliferation was evaluated using KFluor488 EdU kit. Capillary tube network formation was determined by Matrigel assay. Expressions of mRNA and protein levels were detected by real-time PCR and western blotting. B-myb expression significantly decreased, while p53 and p21 expressions increased in the aortas of aged mice. This expression pattern was also found in replicative senescent HAECs and senescent HAECs induced by bleomycin. B-myb knockdown resulted in upregulation of p22 phox , ROS accumulation and cell senescence of HAECs. Downregulation of B-myb significantly inhibited cell proliferation and capillary tube network formation and activated the p53/p21 signalling pathway. Blocking ROS production or inhibiting p53 activation remarkably attenuated SA-β-gal activity and delayed cell senescence induced by B-myb-silencing. Downregulation of B-myb induced senescence by upregulation of p22 phox and activation of the ROS/p53/p21 pathway, in our vascular endothelial cells, suggesting that B-myb may be a novel candidate for regulating cell senescence to protect against endothelial senescence-related cardiovascular diseases. © 2016 John Wiley & Sons Ltd.

  6. IQGAP1-dependent signaling pathway regulates endothelial cell proliferation and angiogenesis.

    Directory of Open Access Journals (Sweden)

    Rosana D Meyer

    Full Text Available Vascular endothelial growth factor receptor-2 (VEGFR-2 signaling is an obligate requirement for normal development and pathological angiogenesis such as cancer and age-related macular degeneration. Although autophosphorylation of tyrosine 1173 (Y1173 of VEGFR-2 is considered a focal point for its angiogenic signal relay, however, the mechanism of phosphorylation of Y1173, signaling proteins that are recruited to this residue and their role in angiogenesis is not fully understood.In this study we demonstrate that c-Src kinase directly through its Src homology 2 (SH2 domain and indirectly via c-Cbl binds to phospho-Y1057 of VEGFR-2. Activation of c-Src kinase by a positive feedback mechanism phosphorylates VEGFR-2 at multi-docking site, Y1173. c-Src also catalyzes tyrosine phosphorylation of IQGAP1 and acts as an adaptor to bridge IQGAP1 to VEGFR-2. In turn, IQGAP1 activates b-Raf and mediates proliferation of endothelial cells. Silencing expression of IQGAP1 and b-Raf revealed that their activity is essential for VEGF to stimulate angiogenesis in an in vivo angiogenesis model of chicken chorioallantoic membrane (CAM.Angiogenesis contributes to the pathology of numerous human diseases ranging from cancer to age-related macular degeneration. Determining molecular mechanism of tyrosine phosphorylation of VEGFR-2 and identification of molecules that are relaying its angiogenic signaling may identify novel targets for therapeutic intervention against angiogenesis-associated diseases. Our study shows that recruitment and activation of c-Src by VEGFR-2 plays a pivotal role in relaying angiogenic signaling of VEGFR-2; it phosphorylates VEGFR-2 at Y1173, facilitates association and activation of IQGAP1 and other signaling proteins to VEGFR-2. IQGAP1-dependent signaling, in part, is critically required for endothelial cell proliferation, a key step in angiogenesis. Thus, Y1057 of VEGFR-2 serves to regulate VEGFR-2 function in a combinatorial manner by

  7. Buddleja officinalis suppresses high glucose-induced vascular smooth muscle cell proliferation: role of mitogen-activated protein kinases, nuclear factor-kappaB and matrix metalloproteinases.

    Science.gov (United States)

    Lee, Yun Jung; Kim, Jin Sook; Kang, Dae Gill; Lee, Ho Sub

    2010-02-01

    Diabetes mellitus is a well-established risk factor for vascular diseases caused by atherosclerosis. In the development of diabetic atherogenesis, vascular smooth muscle cell proliferation is recognized as a key event. Thus, we aimed to investigate whether an ethanol extract of Buddleja officinalis (EBO) suppresses high glucose-induced proliferation in primary cultured human aortic smooth muscle cells (HASMC). [(3)H]-thymidine incorporation revealed that incubation of HASMC with a high concentration of glucose (25 mmol/L) increased cell proliferation. The expression levels of cell cycle protein were also increased by treatment with high glucose concentration. Pretreatment of HASMC with EBO significantly attenuated the increase of high glucose-induced cell proliferation as well as p38 mitogen-activated protein kinases (MAPK) and JNK phosphorylation. EBO suppressed high glucose-induced matrix metalloproteinase (MMP)-9 activity in a dose-dependent manner. In addition, EBO suppressed nuclear factor-kappaB (NF-kappaB) nuclear translocation and transcriptional activity in high glucose conditions. Taken together, the present data suggest that EBO could suppress high glucose-induced atherosclerotic processes through inhibition of p38, JNK, NF-kappaB and MMP signal pathways in HASMC.

  8. Chorein Sensitivity of Actin Polymerization, Cell Shape and Mechanical Stiffness of Vascular Endothelial Cells

    Directory of Open Access Journals (Sweden)

    Ioana Alesutan

    2013-09-01

    Full Text Available Background/Aims: Endothelial cell stiffness plays a key role in endothelium-dependent control of vascular tone and arterial blood pressure. Actin polymerization and distribution of microfilaments is essential for mechanical cell stiffness. Chorein, a protein encoded by the VPS13A gene, defective in chorea-acanthocytosis (ChAc, is involved in neuronal cell survival as well as cortical actin polymerization of erythrocytes and blood platelets. Chorein is expressed in a wide variety of further cells, yet nothing is known about the impact of chorein on cells other than neurons, erythrocytes and platelets. The present study explored whether chorein is expressed in human umbilical vein endothelial cells (HUVECs and addressed the putative role of chorein in the regulation of cytoskeletal architecture, stiffness and survival of those cells. Methods: In HUVECs with or without silencing of the VPS13A gene, VPS13A mRNA expression was determined utilizing quantitative RT-PCR, cytoskeletal organization visualized by confocal microscopy, G/F actin ratio and phosphorylation status of focal adhesion kinase quantified by western blotting, cell death determined by flow cytometry, mechanical properties studied by atomic force microscopy (AFM and cell morphology analysed by scanning ion conductance microscopy (SICM. Results: VPS13A mRNA expression was detectable in HUVECs. Silencing of the VPS13A gene attenuated the filamentous actin network, decreased the ratio of soluble G-actin over filamentous F-actin, reduced cell stiffness and changed cell morphology as compared to HUVECs silenced with negative control siRNA. These effects were paralleled by a significant decrease in FAK phosphorylation following VPS13A silencing. Moreover, silencing of the VPS13A gene increased caspase 3 activity and induced necrosis in HUVECs. Conclusions: Chorein is a novel regulator of cytoskeletal architecture, cell shape, mechanical stiffness and survival of vascular endothelial cells.

  9. Helicobacter pylori induces vascular endothelial growth factor production in gastric epithelial cells through hypoxia-inducible factor-1α-dependent pathway.

    Science.gov (United States)

    Kang, Min-Jung; Song, Eun-Jung; Kim, Bo-Yeon; Kim, Dong-Jae; Park, Jong-Hwan

    2014-12-01

    Although Helicobacter pylori have been known to induce vascular endothelial growth factor (VEGF) production in gastric epithelial cells, the precise mechanism for cellular signaling is incompletely understood. In this study, we investigated the role of bacterial virulence factor and host cellular signaling in VEGF production of H. pylori-infected gastric epithelial cells. We evaluated production of VEGF, activation of nuclear factor nuclear factor-kappaB (NF-κB) and mitogen-activated protein kinases (MAPKs) and hypoxia-inducible factor-1α (HIF-1α) stabilization in gastric epithelial cells infected with H. pylori WT or isogenic mutants deficient in type IV secretion system (T4SS). H. pylori induced VEGF production in gastric epithelial cells via both T4SS-dependent and T4SS-independent pathways, although T4SS-independent pathway seems to be the dominant signaling. The inhibitor assay implicated that activation of NF-κB and MAPKs is dispensable for H. pylori-induced VEGF production in gastric epithelial cells. H. pylori led to HIF-1α stabilization in gastric epithelial cells independently of T4SS, NF-κB, and MAPKs, which was essential for VEGF production in these cells. N-acetyl-cysteine (NAC), a reactive oxygen species (ROS) inhibitor, treatment impaired H. pylori-induced HIF-1α stabilization and VEGF production in gastric epithelial cells. We defined the important role of ROS-HIF-1α axis in VEGF production of H. pylori-infected gastric epithelial cells, and bacterial T4SS has a minor role in H. pylori-induced VEGF production of gastric epithelial cells. © 2014 John Wiley & Sons Ltd.

  10. Human bone marrow mesenchymal stem cells for retinal vascular injury.

    Science.gov (United States)

    Wang, Jin-Da; An, Ying; Zhang, Jing-Shang; Wan, Xiu-Hua; Jonas, Jost B; Xu, Liang; Zhang, Wei

    2017-09-01

    To examine the potential of intravitreally implanted human bone marrow-derived mesenchymal stem cells (BMSCs) to affect vascular repair and the blood-retina barrier in mice and rats with oxygen-induced retinopathy, diabetic retinopathy or retinal ischaemia-reperfusion damage. Three study groups (oxygen-induced retinopathy group: 18 C57BL/6J mice; diabetic retinopathy group: 15 rats; retinal ischaemia-reperfusion model: 18 rats) received BMSCs injected intravitreally. Control groups (oxygen-induced retinopathy group: 12 C57BL/6J mice; diabetic retinopathy group: 15 rats; retinal ischaemia-reperfusion model: 18 rats) received an intravitreal injection of phosphate-buffered saline. We applied immunohistological techniques to measure retinal vascularization, spectroscopic measurements of intraretinally extravasated fluorescein-conjugated dextran to quantify the blood-retina barrier breakdown, and histomorphometry to assess retinal thickness and retinal ganglion cell count. In the oxygen-induced retinopathy model, the study group with intravitreally injected BMSCs as compared with the control group showed a significantly (p = 0.001) smaller area of retinal neovascularization. In the diabetic retinopathy model, study group and control group did not differ significantly in the amount of intraretinally extravasated dextran. In the retinal ischaemia-reperfusion model, on the 7th day after retina injury, the retina was significantly thicker in the study group than in the control group (p = 0.02), with no significant difference in the retinal ganglion cell count (p = 0.36). Intravitreally implanted human BMSCs were associated with a reduced retinal neovascularization in the oxygen-induced retinopathy model and with a potentially cell preserving effect in the retinal ischaemia-reperfusion model. Intravitreal BMSCs may be of potential interest for the therapy of retinal vascular disorders. © 2016 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley

  11. Signal transduction by VEGF receptors in regulation of angiogenesis and lymphangiogenesis

    International Nuclear Information System (INIS)

    Shibuya, Masabumi; Claesson-Welsh, Lena

    2006-01-01

    The VEGF/VPF (vascular endothelial growth factor/vascular permeability factor) ligands and receptors are crucial regulators of vasculogenesis, angiogenesis, lymphangiogenesis and vascular permeability in vertebrates. VEGF-A, the prototype VEGF ligand, binds and activates two tyrosine kinase receptors: VEGFR1 (Flt-1) and VEGFR2 (KDR/Flk-1). VEGFR1, which occurs in transmembrane and soluble forms, negatively regulates vasculogenesis and angiogenesis during early embryogenesis, but it also acts as a positive regulator of angiogenesis and inflammatory responses, playing a role in several human diseases such as rheumatoid arthritis and cancer. The soluble VEGFR1 is overexpressed in placenta in preeclampsia patients. VEGFR2 has critical functions in physiological and pathological angiogenesis through distinct signal transduction pathways regulating proliferation and migration of endothelial cells. VEGFR3, a receptor for the lymphatic growth factors VEGF-C and VEGF-D, but not for VEGF-A, regulates vascular and lymphatic endothelial cell function during embryogenesis. Loss-of-function variants of VEGFR3 have been identified in lymphedema. Formation of tumor lymphatics may be stimulated by tumor-produced VEGF-C, allowing increased spread of tumor metastases through the lymphatics. Mapping the signaling system of these important receptors may provide the knowledge necessary to suppress specific signaling pathways in major human diseases

  12. RNA interference-mediated silencing of speckle-type POZ protein promotes apoptosis of renal cell cancer cells.

    Science.gov (United States)

    Liu, Xiaoxia; Sun, Guiling; Sun, Xiuju

    2016-01-01

    This study aimed to investigate the effects of silencing the speckle-type POZ protein (SPOP) gene on renal cell cancer (RCC) cells and to explore its possible mechanism. The A498 and ACHN RCC cells were transfected with small interference RNA (siRNA)-SPOP by lipofection methods. The silencing efficiency was monitored by quantitative real-time polymerase chain reaction and Western blot. The effects of SPOP silencing on cell apoptosis, cell viability, colony formation ability, cell migration ability, and chemosensitivity to Sorafenib were assessed by flow cytometry, an MTT assay, a colony formation assay, a trans-well migration assay, and a CCK-8 assay, respectively. Its effects on the expression of several cytokines were determined by a protein microarray. Relevant signaling pathways were also analyzed. Compared with the control group, the cell apoptosis rate was significantly higher; the cell viability, the colony formation, and migration ability were significantly decreased in the siRNA-SPOP group. The protein microarray screening showed that the expression of vascular endothelial growth factor receptor, matrix metallopeptidase-9, vascular cell adhesion molecule-1, and stromal cell-derived factor-1 in the siRNA group was significantly decreased and that the expression of granulocyte-macrophage colony-stimulating factor and E-cadherin was significantly increased (Pmatrix organization signal pathway. SPOP gene silencing induced cell apoptosis, decreased cell viability, colony formation, and migration ability, and elevated the drug sensitivity in the RCC cells. A possible mechanism is that silencing SPOP induces the differential expression of E-cadherin, vascular endothelial growth factor receptor, matrix metallopeptidase-9, and vascular cell adhesion molecule, which are related to the integrin-mediated cell surface interactions and extracellular matrix organization signaling pathway.

  13. Selective Inhibitory Effect of Epigallocatechin-3-gallate on Migration of Vascular Smooth Muscle Cells

    Directory of Open Access Journals (Sweden)

    Jong-Chul Park

    2010-11-01

    Full Text Available In order to prevent restenosis after angioplasty or stenting, one of the most popular targets is suppression of the abnormal growth and excess migration of vascular smooth muscle cells (VSMCs with drugs. However, the drugs also adversely affect vascular endothelial cells (VECs, leading to the induction of late thrombosis. We have investigated the effect of epigallocatechin-3-gallate (EGCG on the proliferation and migration of VECs and VSMCs. Both cells showed dose-dependent decrease of viability in response to EGCG while they have different IC50 values of EGCG (VECs, 150 mM and VSMCs, 1050 mM. Incubating both cells with EGCG resulted in significant reduction in cell proliferation irrespective of cell type. The proliferation of VECs were greater affected than that of VSMCs at the same concentrations of EGCG. EGCG exerted differential migration-inhibitory activity in VECs vs. VSMCs. The migration of VECs was not attenuated by 200 mM EGCG, but that of VSMCs was significantly inhibited at the same concentration of EGCG. It is suggested that that EGCG can be effectively used as an efficient drug for vascular diseases or stents due to its selective activity, completely suppressing the proliferation and migration of VSMCs, but not adversely affecting VECs migration in blood vessels.

  14. VEGFR tyrosine kinase inhibitor II (VRI) induced vascular insufficiency in zebrafish as a model for studying vascular toxicity and vascular preservation

    International Nuclear Information System (INIS)

    Li, Shang; Dang, Yuan Ye; Oi Lam Che, Ginny; Kwan, Yiu Wa; Chan, Shun Wan; Leung, George Pak Heng; Lee, Simon Ming Yuen; Hoi, Maggie Pui Man

    2014-01-01

    In ischemic disorders such as chronic wounds and myocardial ischemia, there is inadequate tissue perfusion due to vascular insufficiency. Besides, it has been observed that prolonged use of anti-angiogenic agents in cancer therapy produces cardiovascular toxicity caused by impaired vessel integrity and regeneration. In the present study, we used VEGFR tyrosine kinase inhibitor II (VRI) to chemically induce vascular insufficiency in zebrafish in vivo and human umbilical vein endothelial cells (HUVEC) in vitro to further study the mechanisms of vascular morphogenesis in these pathological conditions. We also explored the possibility of treating vascular insufficiency by enhancing vascular regeneration and repair with pharmacological intervention. We observed that pretreatment of VRI induced blood vessel loss in developing zebrafish by inhibiting angiogenesis and increasing endothelial cell apoptosis, accompanied by down-regulation of kdr, kdrl and flt-1 genes expression. The VRI-induced blood vessel loss in zebrafish could be restored by post-treatment of calycosin, a cardiovascular protective isoflavone. Similarly, VRI induced cytotoxicity and apoptosis in HUVEC which could be rescued by calycosin post-treatment. Further investigation of the underlying mechanisms showed that the PI3K/AKT/Bad cell survival pathway was a main contributor of the vascular regenerative effect of calycosin. These findings indicated that the cardiovascular toxicity in anti-angiogenic therapy was mainly caused by insufficient endothelial cell survival, suggesting its essential role in vascular integrity, repair and regeneration. In addition, we showed that VRI-induced blood vessel loss in zebrafish represented a simple and effective in vivo model for studying vascular insufficiency and evaluating cancer drug vascular toxicities. - Highlights: • In vivo VRI model • Rescue effects of calycosin • Calycosin EC survival pathways

  15. ALK1 signaling inhibits angiogenesis by cooperating with the Notch pathway.

    Science.gov (United States)

    Larrivée, Bruno; Prahst, Claudia; Gordon, Emma; del Toro, Raquel; Mathivet, Thomas; Duarte, Antonio; Simons, Michael; Eichmann, Anne

    2012-03-13

    Activin receptor-like kinase 1 (ALK1) is an endothelial-specific member of the TGF-β/BMP receptor family that is inactivated in patients with hereditary hemorrhagic telangiectasia (HHT). How ALK1 signaling regulates angiogenesis remains incompletely understood. Here we show that ALK1 inhibits angiogenesis by cooperating with the Notch pathway. Blocking Alk1 signaling during postnatal development in mice leads to retinal hypervascularization and the appearance of arteriovenous malformations (AVMs). Combined blockade of Alk1 and Notch signaling further exacerbates hypervascularization, whereas activation of Alk1 by its high-affinity ligand BMP9 rescues hypersprouting induced by Notch inhibition. Mechanistically, ALK1-dependent SMAD signaling synergizes with activated Notch in stalk cells to induce expression of the Notch targets HEY1 and HEY2, thereby repressing VEGF signaling, tip cell formation, and endothelial sprouting. Taken together, these results uncover a direct link between ALK1 and Notch signaling during vascular morphogenesis that may be relevant to the pathogenesis of HHT vascular lesions. Copyright © 2012 Elsevier Inc. All rights reserved.

  16. Compressive elasticity of three-dimensional nanofiber matrix directs mesenchymal stem cell differentiation to vascular cells with endothelial or smooth muscle cell markers.

    Science.gov (United States)

    Wingate, K; Bonani, W; Tan, Y; Bryant, S J; Tan, W

    2012-04-01

    The importance of mesenchymal stem cells (MSC) in vascular regeneration is becoming increasingly recognized. However, few in vitro studies have been performed to identify the effects of environmental elasticity on the differentiation of MSC into vascular cell types. Electrospinning and photopolymerization techniques were used to fabricate a three-dimensional (3-D) polyethylene glycol dimethacrylate nanofiber hydrogel matrix with tunable elasticity for use as a cellular substrate. Compression testing demonstrated that the elastic modulus of the hydrated 3-D matrices ranged from 2 to 15 kPa, similar to the in vivo elasticity of the intima basement membrane and media layer. MSC seeded on rigid matrices (8-15 kPa) showed an increase in cell area compared with those seeded on soft matrices (2-5 kPa). Furthermore, the matrix elasticity guided the cells to express different vascular-specific phenotypes with high differentiation efficiency. Around 95% of MSC seeded on the 3-D matrices with an elasticity of 3 kPa showed Flk-1 endothelial markers within 24h, while only 20% of MSC seeded on the matrices with elasticity >8 kPa demonstrated Flk-1 marker. In contrast, ∼80% of MSC seeded on 3-D matrices with elasticity >8 kPa demonstrated smooth muscle α-actin marker within 24h, while fewer than 10% of MSC seeded on 3-D matrices with elasticity elasticity of the substrate could be a powerful tool for vascular tissue regeneration. Copyright © 2012 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  17. β1 integrin signaling promotes neuronal migration along vascular scaffolds in the post-stroke brain

    Directory of Open Access Journals (Sweden)

    Teppei Fujioka

    2017-02-01

    Full Text Available Cerebral ischemic stroke is a main cause of chronic disability. However, there is currently no effective treatment to promote recovery from stroke-induced neurological symptoms. Recent studies suggest that after stroke, immature neurons, referred to as neuroblasts, generated in a neurogenic niche, the ventricular-subventricular zone, migrate toward the injured area, where they differentiate into mature neurons. Interventions that increase the number of neuroblasts distributed at and around the lesion facilitate neuronal repair in rodent models for ischemic stroke, suggesting that promoting neuroblast migration in the post-stroke brain could improve efficient neuronal regeneration. To move toward the lesion, neuroblasts form chain-like aggregates and migrate along blood vessels, which are thought to increase their migration efficiency. However, the molecular mechanisms regulating these migration processes are largely unknown. Here we studied the role of β1-class integrins, transmembrane receptors for extracellular matrix proteins, in these migrating neuroblasts. We found that the neuroblast chain formation and blood vessel-guided migration critically depend on β1 integrin signaling. β1 integrin facilitated the adhesion of neuroblasts to laminin and the efficient translocation of their soma during migration. Moreover, artificial laminin-containing scaffolds promoted neuroblast chain formation and migration toward the injured area. These data suggest that laminin signaling via β1 integrin supports vasculature-guided neuronal migration to efficiently supply neuroblasts to injured areas. This study also highlights the importance of vascular scaffolds for cell migration in development and regeneration.

  18. α-Iso-Cubebene Inhibits PDGF-Induced Vascular Smooth Muscle Cell Proliferation by Suppressing Osteopontin Expression

    Science.gov (United States)

    Jang, Min A.; Lee, Seung Jin; Baek, Seung Eun; Park, So Youn; Choi, Young Whan; Kim, Chi Dae

    2017-01-01

    α-Iso-cubebene (ICB) is a dibenzocyclooctadiene lignin contained in Schisandra chinensis (SC), a well-known medicinal herb that ameliorates cardiovascular symptoms. Thus, we examined the effect of ICB on vascular smooth muscle cell (VSMC) proliferation, a key feature of diverse vascular diseases. When VSMCs primary cultured from rat thoracic aorta were stimulated with PDGF (1–10 ng/ml), cell proliferation and osteopontin (OPN) expression were concomitantly up-regulated, but these effects were attenuated when cells were treated with MPIIIB10, a neutralizing monoclonal antibody for OPN. In aortic tissues exposed to PDGF, sprouting VSMC numbers increased, which was attenuated in tissues from OPN-deficient mice. Furthermore, VSMC proliferation and OPN expression induced by PDGF were attenuated dose-dependently by ICB (10 or 30 μg/ml). Reporter assays conducted using OPN promoter-luciferase constructs showed that the promoter region 538–234 bp of the transcription start site was responsible for transcriptional activity enhancement by PDGF, which was significantly inhibited by ICB. Putative binding sites for AP-1 and C/EBPβ in the indicated promoter region were suggested by TF Search, and increased binding of AP-1 and C/EBPβ in PDGF-treated VSMCs was demonstrated using a ChIP assay. The increased bindings of AP-1 and C/EBPβ into OPN promoter were attenuated by ICB. Moreover, the PDGF-induced expression of OPN was markedly attenuated in VSMCs transfected with siRNA for AP-1 and C/EBPβ. These results indicate that ICB inhibit VSMC proliferation by inhibiting the AP-1 and C/EBPβ signaling pathways and thus downregulating OPN expression. PMID:28114367

  19. Response of the sensorimotor cortex of cerebral palsy rats receiving transplantation of vascular endothelial growth factor 165-transfected neural stem cells

    Institute of Scientific and Technical Information of China (English)

    Jielu Tan; Xiangrong Zheng; Shanshan Zhang; Yujia Yang; Xia Wang; Xiaohe Yu; Le Zhong

    2014-01-01

    Neural stem cells are characterized by the ability to differentiate and stably express exogenous ge-nes. Vascular endothelial growth factor plays a role in protecting local blood vessels and neurons of newborn rats with hypoxic-ischemic encephalopathy. Transplantation of vascular endothelial growth factor-transfected neural stem cells may be neuroprotective in rats with cerebral palsy. In this study, 7-day-old Sprague-Dawley rats were divided into ifve groups: (1) sham operation (control), (2) cerebral palsy model alone or with (3) phosphate-buffered saline, (4) vascular en-dothelial growth factor 165 + neural stem cells, or (5) neural stem cells alone. hTe cerebral palsy model was established by ligating the letf common carotid artery followed by exposure to hypox-ia. Phosphate-buffered saline, vascular endothelial growth factor + neural stem cells, and neural stem cells alone were administered into the sensorimotor cortex using the stereotaxic instrument and microsyringe. Atfer transplantation, the radial-arm water maze test and holding test were performed. Immunohistochemistry for vascular endothelial growth factor and histology using hematoxylin-eosin were performed on cerebral cortex. Results revealed that the number of vas-cular endothelial growth factor-positive cells in cerebral palsy rats transplanted with vascular endothelial growth factor-transfected neural stem cells was increased, the time for ifnding water and the ifnding repetitions were reduced, the holding time was prolonged, and the degree of cell degeneration or necrosis was reduced. hTese ifndings indicate that the transplantation of vascu-lar endothelial growth factor-transfected neural stem cells alleviates brain damage and cognitive deifcits, and is neuroprotective in neonatal rats with hypoxia ischemic-mediated cerebral palsy.

  20. Prevention of vascular inflammation by nanoparticle targeting of adherent neutrophils

    Science.gov (United States)

    Wang, Zhenjia; Li, Jing; Cho, Jaehyung; Malik, Asrar B.

    2014-03-01

    Inflammatory diseases such as acute lung injury and ischaemic tissue injury are caused by the adhesion of a type of white blood cell--polymorphonuclear neutrophils--to the lining of the circulatory system or vascular endothelium and unchecked neutrophil transmigration. Nanoparticle-mediated targeting of activated neutrophils on vascular endothelial cells at the site of injury may be a useful means of directly inactivating neutrophil transmigration and hence mitigating vascular inflammation. Here, we report a method employing drug-loaded albumin nanoparticles, which efficiently deliver drugs into neutrophils adherent to the surface of the inflamed endothelium. Using intravital microscopy of tumour necrosis factor-α-challenged mouse cremaster post-capillary venules, we demonstrate that fluorescently tagged albumin nanoparticles are largely internalized by neutrophils adherent to the activated endothelium via cell surface Fcɣ receptors. Administration of albumin nanoparticles loaded with the spleen tyrosine kinase inhibitor, piceatannol, which blocks `outside-in' β2 integrin signalling in leukocytes, detached the adherent neutrophils and elicited their release into the circulation. Thus, internalization of drug-loaded albumin nanoparticles into neutrophils inactivates the pro-inflammatory function of activated neutrophils, thereby offering a promising approach for treating inflammatory diseases resulting from inappropriate neutrophil sequestration and activation.

  1. Macrophages control vascular stem/progenitor cell plasticity through tumor necrosis factor-α-mediated nuclear factor-κB activation.

    Science.gov (United States)

    Wong, Mei Mei; Chen, Yikuan; Margariti, Andriani; Winkler, Bernhard; Campagnolo, Paola; Potter, Claire; Hu, Yanhua; Xu, Qingbo

    2014-03-01

    Vascular lineage differentiation of stem/progenitor cells can contribute to both tissue repair and exacerbation of vascular diseases such as in vein grafts. The role of macrophages in controlling vascular progenitor differentiation is largely unknown and may play an important role in graft development. This study aims to identify the role of macrophages in vascular stem/progenitor cell differentiation and thereafter elucidate the mechanisms that are involved in the macrophage- mediated process. We provide in vitro evidence that macrophages can induce endothelial cell (EC) differentiation of the stem/progenitor cells while simultaneously inhibiting their smooth muscle cell differentiation. Mechanistically, both effects were mediated by macrophage-derived tumor necrosis factor-α (TNF-α) via TNF-α receptor 1 and canonical nuclear factor-κB activation. Although the overexpression of p65 enhanced EC (or attenuated smooth muscle cell) differentiation, p65 or TNF-α receptor 1 knockdown using lentiviral short hairpin RNA inhibited EC (or rescued smooth muscle cell) differentiation in response to TNF-α. Furthermore, TNF-α-mediated EC differentiation was driven by direct binding of nuclear factor-κB (p65) to specific VE-cadherin promoter sequences. Subsequent experiments using an ex vivo decellularized vessel scaffold confirmed an increase in the number of ECs and reduction in smooth muscle cell marker expression in the presence of TNF-α. The lack of TNF-α in a knockout mouse model of vein graft decreased endothelialization and significantly increased thrombosis formation. Our study highlights the role of macrophages in directing vascular stem/progenitor cell lineage commitment through TNF-α-mediated TNF-α receptor 1 and nuclear factor-κB activation that is likely required for endothelial repair in vascular diseases such as vein graft.

  2. Enhanced adherence of mouse fibroblast and vascular cells to plasma modified polyethylene

    Energy Technology Data Exchange (ETDEWEB)

    Reznickova, Alena, E-mail: alena.reznickova@vscht.cz [Department of Solid State Engineering, Institute of Chemical Technology Prague, 166 28 Prague 6 (Czech Republic); Novotna, Zdenka, E-mail: zdenka1.novotna@vscht.cz [Department of Solid State Engineering, Institute of Chemical Technology Prague, 166 28 Prague 6 (Czech Republic); Kolska, Zdenka [Faculty of Science, J.E. Purkyně University, 400 96 Usti nad Labem (Czech Republic); Kasalkova, Nikola Slepickova [Department of Solid State Engineering, Institute of Chemical Technology Prague, 166 28 Prague 6 (Czech Republic); Rimpelova, Silvie [Department of Biochemistry and Microbiology, Institute of Chemical Technology Prague, 166 28 Prague 6 (Czech Republic); Svorcik, Vaclav [Department of Solid State Engineering, Institute of Chemical Technology Prague, 166 28 Prague 6 (Czech Republic)

    2015-07-01

    Since the last decade, tissue engineering has shown a sensational promise in providing more viable alternatives to surgical procedures for harvested tissues, implants and prostheses. Biomedical polymers, such as low-density polyethylene (LDPE), high-density polyethylene (HDPE) and ultra-high molecular weight polyethylene (UHMWPE), were activated by Ar plasma discharge. Degradation of polymer chains was examined by determination of the thickness of ablated layer. The amount of an ablated polymer layer was measured by gravimetry. Contact angle, measured by goniometry, was studied as a function of plasma exposure and post-exposure aging times. Chemical structure of modified polymers was characterized by angle resolved X-ray photoelectron spectroscopy. Surface chemistry and polarity of the samples were investigated by electrokinetic analysis. Changes in surface morphology were followed using atomic force microscopy. Cytocompatibility of plasma activated polyethylene foils was studied using two distinct model cell lines; VSMCs (vascular smooth muscle cells) as a model for vascular graft testing and connective tissue cells L929 (mouse fibroblasts) approved for standardized material cytotoxicity testing. Specifically, the cell number, morphology, and metabolic activity of the adhered and proliferated cells on the polyethylene matrices were studied in vitro. It was found that the plasma treatment caused ablation of the polymers, resulting in dramatic changes in their surface morphology and roughness. ARXPS and electrokinetic measurements revealed oxidation of the polymer surface. It was found that plasma activation has a positive effect on the adhesion and proliferation of VSMCs and L929 cells. - Highlights: • Plasma activation of LDPE, HDPE and UHMWPE • Study of surface properties by several techniques: ARXPS, AFM, zeta-potential, and goniometry • Investigation of adhesion and spreading of vascular smooth muscle cells (VSMCs) and mouse fibroblasts (L929)

  3. A bHLH-Based Feedback Loop Restricts Vascular Cell Proliferation in Plants.

    Science.gov (United States)

    Vera-Sirera, Francisco; De Rybel, Bert; Úrbez, Cristina; Kouklas, Evangelos; Pesquera, Marta; Álvarez-Mahecha, Juan Camilo; Minguet, Eugenio G; Tuominen, Hannele; Carbonell, Juan; Borst, Jan Willem; Weijers, Dolf; Blázquez, Miguel A

    2015-11-23

    Control of tissue dimensions in multicellular organisms requires the precise quantitative regulation of mitotic activity. In plants, where cells are immobile, tissue size is achieved through control of both cell division orientation and mitotic rate. The bHLH transcription factor heterodimer formed by target of monopteros5 (TMO5) and lonesome highway (LHW) is a central regulator of vascular width-increasing divisions. An important unanswered question is how its activity is limited to specify vascular tissue dimensions. Here we identify a regulatory network that restricts TMO5/LHW activity. We show that thermospermine synthase ACAULIS5 antagonizes TMO5/LHW activity by promoting the accumulation of SAC51-LIKE (SACL) bHLH transcription factors. SACL proteins heterodimerize with LHW-therefore likely competing with TMO5/LHW interactions-prevent activation of TMO5/LHW target genes, and suppress the over-proliferation caused by excess TMO5/LHW activity. These findings connect two thus-far disparate pathways and provide a mechanistic understanding of the quantitative control of vascular tissue growth. Copyright © 2015 Elsevier Inc. All rights reserved.

  4. Ubiquitination of basal VEGFR2 regulates signal transduction and endothelial function

    Directory of Open Access Journals (Sweden)

    Gina A. Smith

    2017-10-01

    Full Text Available Cell surface receptors can undergo recycling or proteolysis but the cellular decision-making events that sort between these pathways remain poorly defined. Vascular endothelial growth factor A (VEGF-A and vascular endothelial growth factor receptor 2 (VEGFR2 regulate signal transduction and angiogenesis, but how signaling and proteolysis is regulated is not well understood. Here, we provide evidence that a pathway requiring the E1 ubiquitin-activating enzyme UBA1 controls basal VEGFR2 levels, hence metering plasma membrane receptor availability for the VEGF-A-regulated endothelial cell response. VEGFR2 undergoes VEGF-A-independent constitutive degradation via a UBA1-dependent ubiquitin-linked pathway. Depletion of UBA1 increased VEGFR2 recycling from endosome-to-plasma membrane and decreased proteolysis. Increased membrane receptor availability after UBA1 depletion elevated VEGF-A-stimulated activation of key signaling enzymes such as PLCγ1 and ERK1/2. Although UBA1 depletion caused an overall decrease in endothelial cell proliferation, surviving cells showed greater VEGF-A-stimulated responses such as cell migration and tubulogenesis. Our study now suggests that a ubiquitin-linked pathway regulates the balance between receptor recycling and degradation which in turn impacts on the intensity and duration of VEGF-A-stimulated signal transduction and the endothelial response.

  5. Mitochondrial metabolism and the control of vascular smooth muscle cell proliferation

    Directory of Open Access Journals (Sweden)

    Mario eChiong

    2014-12-01

    Full Text Available Differentiation and dedifferentiation of vascular smooth muscle cells (VSMCs are essential processes of vascular development. VSMCs have biosynthetic, proliferative and contractile roles in the vessel wall. Alterations in the differentiated state of the VSMCs play a critical role in the pathogenesis of a variety of cardiovascular diseases, including atherosclerosis, hypertension and vascular stenosis. This review provides an overview of the current state of knowledge of molecular mechanisms involved in the control of VSMC proliferation, with particular focus on mitochondrial metabolism. Mitochondrial activity can be controlled by regulating mitochondrial dynamics, i.e. mitochondrial fusion and fission, and by regulating mitochondrial calcium handling through the interaction with the endoplasmic reticulum (ER. Alterations in both VSMC proliferation and mitochondrial function can be triggered by dysregulation of mitofusin-2, a small GTPase associated with mitochondrial fusion and mitochondrial-ER interaction. Several lines of evidence highlight the relevance of mitochondrial metabolism in the control of VSMC proliferation, indicating a new area to be explored in the treatment of vascular diseases.

  6. Vascular niche promotes hematopoietic multipotent progenitor formation from pluripotent stem cells

    Science.gov (United States)

    Gori, Jennifer L.; Butler, Jason M.; Chan, Yan-Yi; Chandrasekaran, Devikha; Poulos, Michael G.; Ginsberg, Michael; Nolan, Daniel J.; Elemento, Olivier; Wood, Brent L.; Adair, Jennifer E.; Rafii, Shahin; Kiem, Hans-Peter

    2015-01-01

    Pluripotent stem cells (PSCs) represent an alternative hematopoietic stem cell (HSC) source for treating hematopoietic disease. The limited engraftment of human PSC–derived (hPSC-derived) multipotent progenitor cells (MPP) has hampered the clinical application of these cells and suggests that MPP require additional cues for definitive hematopoiesis. We hypothesized that the presence of a vascular niche that produces Notch ligands jagged-1 (JAG1) and delta-like ligand-4 (DLL4) drives definitive hematopoiesis. We differentiated hes2 human embryonic stem cells (hESC) and Macaca nemestrina–induced PSC (iPSC) line-7 with cytokines in the presence or absence of endothelial cells (ECs) that express JAG1 and DLL4. Cells cocultured with ECs generated substantially more CD34+CD45+ hematopoietic progenitors compared with cells cocultured without ECs or with ECs lacking JAG1 or DLL4. EC-induced cells exhibited Notch activation and expressed HSC-specific Notch targets RUNX1 and GATA2. EC-induced PSC-MPP engrafted at a markedly higher level in NOD/SCID/IL-2 receptor γ chain–null (NSG) mice compared with cytokine-induced cells, and low-dose chemotherapy-based selection further increased engraftment. Long-term engraftment and the myeloid-to-lymphoid ratio achieved with vascular niche induction were similar to levels achieved for cord blood–derived MPP and up to 20-fold higher than those achieved with hPSC-derived MPP engraftment. Our findings indicate that endothelial Notch ligands promote PSC-definitive hematopoiesis and production of long-term engrafting CD34+ cells, suggesting these ligands are critical for HSC emergence. PMID:25664855

  7. Generation of a functional and durable vascular niche by the adenoviral E4ORF1 gene.

    Science.gov (United States)

    Seandel, Marco; Butler, Jason M; Kobayashi, Hideki; Hooper, Andrea T; White, Ian A; Zhang, Fan; Vertes, Eva L; Kobayashi, Mariko; Zhang, Yan; Shmelkov, Sergey V; Hackett, Neil R; Rabbany, Sina; Boyer, Julie L; Rafii, Shahin

    2008-12-09

    Vascular cells contribute to organogenesis and tumorigenesis by producing unknown factors. Primary endothelial cells (PECs) provide an instructive platform for identifying factors that support stem cell and tumor homeostasis. However, long-term maintenance of PECs requires stimulation with cytokines and serum, resulting in loss of their angiogenic properties. To circumvent this hurdle, we have discovered that the adenoviral E4ORF1 gene product maintains long-term survival and facilitates organ-specific purification of PECs, while preserving their vascular repertoire for months, in serum/cytokine-free cultures. Lentiviral introduction of E4ORF1 into human PECs (E4ORF1(+) ECs) increased the long-term survival of these cells in serum/cytokine-free conditions, while preserving their in vivo angiogenic potential for tubulogenesis and sprouting. Although E4ORF1, in the absence of mitogenic signals, does not induce proliferation of ECs, stimulation with VEGF-A and/or FGF-2 induced expansion of E4ORF1(+) ECs in a contact-inhibited manner. Indeed, VEGF-A-induced phospho MAPK activation of E4ORF1(+) ECs is comparable with that of naive PECs, suggesting that the VEGF receptors remain functional upon E4ORF1 introduction. E4ORF1(+) ECs inoculated in implanted Matrigel plugs formed functional, patent, humanized microvessels that connected to the murine circulation. E4ORF1(+) ECs also incorporated into neo-vessels of human tumor xenotransplants and supported serum/cytokine-free expansion of leukemic and embryonal carcinoma cells. E4ORF1 augments survival of PECs in part by maintaining FGF-2/FGF-R1 signaling and through tonic Ser-473 phosphorylation of Akt, thereby activating the mTOR and NF-kappaB pathways. Therefore, E4ORF1(+) ECs establish an Akt-dependent durable vascular niche not only for expanding stem and tumor cells but also for interrogating the roles of vascular cells in regulating organ-specific vascularization and tumor neo-angiogenesis.

  8. Generation of a functional and durable vascular niche by the adenoviral E4ORF1 gene

    Science.gov (United States)

    Seandel, Marco; Butler, Jason M.; Kobayashi, Hideki; Hooper, Andrea T.; White, Ian A.; Zhang, Fan; Vertes, Eva L.; Kobayashi, Mariko; Zhang, Yan; Shmelkov, Sergey V.; Hackett, Neil R.; Rabbany, Sina; Boyer, Julie L.; Rafii, Shahin

    2008-01-01

    Vascular cells contribute to organogenesis and tumorigenesis by producing unknown factors. Primary endothelial cells (PECs) provide an instructive platform for identifying factors that support stem cell and tumor homeostasis. However, long-term maintenance of PECs requires stimulation with cytokines and serum, resulting in loss of their angiogenic properties. To circumvent this hurdle, we have discovered that the adenoviral E4ORF1 gene product maintains long-term survival and facilitates organ-specific purification of PECs, while preserving their vascular repertoire for months, in serum/cytokine-free cultures. Lentiviral introduction of E4ORF1 into human PECs (E4ORF1+ ECs) increased the long-term survival of these cells in serum/cytokine-free conditions, while preserving their in vivo angiogenic potential for tubulogenesis and sprouting. Although E4ORF1, in the absence of mitogenic signals, does not induce proliferation of ECs, stimulation with VEGF-A and/or FGF-2 induced expansion of E4ORF1+ ECs in a contact-inhibited manner. Indeed, VEGF-A-induced phospho MAPK activation of E4ORF1+ ECs is comparable with that of naive PECs, suggesting that the VEGF receptors remain functional upon E4ORF1 introduction. E4ORF1+ ECs inoculated in implanted Matrigel plugs formed functional, patent, humanized microvessels that connected to the murine circulation. E4ORF1+ ECs also incorporated into neo-vessels of human tumor xenotransplants and supported serum/cytokine-free expansion of leukemic and embryonal carcinoma cells. E4ORF1 augments survival of PECs in part by maintaining FGF-2/FGF-R1 signaling and through tonic Ser-473 phosphorylation of Akt, thereby activating the mTOR and NF-κB pathways. Therefore, E4ORF1+ ECs establish an Akt-dependent durable vascular niche not only for expanding stem and tumor cells but also for interrogating the roles of vascular cells in regulating organ-specific vascularization and tumor neo-angiogenesis. PMID:19036927

  9. Determinants of cell-to-cell variability in protein kinase signaling.

    Science.gov (United States)

    Jeschke, Matthias; Baumgärtner, Stephan; Legewie, Stefan

    2013-01-01

    Cells reliably sense environmental changes despite internal and external fluctuations, but the mechanisms underlying robustness remain unclear. We analyzed how fluctuations in signaling protein concentrations give rise to cell-to-cell variability in protein kinase signaling using analytical theory and numerical simulations. We characterized the dose-response behavior of signaling cascades by calculating the stimulus level at which a pathway responds ('pathway sensitivity') and the maximal activation level upon strong stimulation. Minimal kinase cascades with gradual dose-response behavior show strong variability, because the pathway sensitivity and the maximal activation level cannot be simultaneously invariant. Negative feedback regulation resolves this trade-off and coordinately reduces fluctuations in the pathway sensitivity and maximal activation. Feedbacks acting at different levels in the cascade control different aspects of the dose-response curve, thereby synergistically reducing the variability. We also investigated more complex, ultrasensitive signaling cascades capable of switch-like decision making, and found that these can be inherently robust to protein concentration fluctuations. We describe how the cell-to-cell variability of ultrasensitive signaling systems can be actively regulated, e.g., by altering the expression of phosphatase(s) or by feedback/feedforward loops. Our calculations reveal that slow transcriptional negative feedback loops allow for variability suppression while maintaining switch-like decision making. Taken together, we describe design principles of signaling cascades that promote robustness. Our results may explain why certain signaling cascades like the yeast pheromone pathway show switch-like decision making with little cell-to-cell variability.

  10. Experimental studies of mitochondrial function in CADASIL vascular smooth muscle cells

    International Nuclear Information System (INIS)

    Viitanen, Matti; Sundström, Erik; Baumann, Marc; Poyhonen, Minna; Tikka, Saara; Behbahani, Homira

    2013-01-01

    Cerebral Autosomal Dominant Arteriopathy with Subcortical Infarcts and Leukoencephalopathy (CADASIL) is a familiar fatal progressive degenerative disorder characterized by cognitive decline, and recurrent stroke in young adults. Pathological features include a dramatic reduction of brain vascular smooth muscle cells and severe arteriopathy with the presence of granular osmophilic material in the arterial walls. Here we have investigated the cellular and mitochondrial function in vascular smooth muscle cell lines (VSMCs) established from CADASIL mutation carriers (R133C) and healthy controls. We found significantly lower proliferation rates in CADASIL VSMC as compared to VSMC from controls. Cultured CADASIL VSMCs were not more vulnerable than control cells to a number of toxic substances. Morphological studies showed reduced mitochondrial connectivity and increased number of mitochondria in CADASIL VSMCs. Transmission electron microscopy analysis demonstrated increased irregular and abnormal mitochondria in CADASIL VSMCs. Measurements of mitochondrial membrane potential (Δψ m ) showed a lower percentage of fully functional mitochondria in CADASIL VSMCs. For a number of genes previously reported to be changed in CADASIL VSMCs, immunoblotting analysis demonstrated a significantly reduced SOD1 expression. These findings suggest that alteration of proliferation and mitochondrial function in CADASIL VSMCs might have an effect on vital cellular functions important for CADASIL pathology. -- Highlights: ► CADASIL is an inherited disease of cerebral vascular cells. ► Mitochondrial dysfunction has been implicated in the pathogenesis of CADASIL. ► Lower proliferation rates in CADASIL VSMC. ► Increased irregular and abnormal mitochondria and lower mitochondrial membrane potential in CADASIL VSMCs. ► Reduced mitochondrial connectivity and increased number of mitochondria in CADASIL VSMCs.

  11. Experimental studies of mitochondrial function in CADASIL vascular smooth muscle cells

    Energy Technology Data Exchange (ETDEWEB)

    Viitanen, Matti [Division of Clinical Geriatrics, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Stockholm (Sweden); Department of Geriatrics, Turku City Hospital and University of Turku, Turku (Finland); Sundström, Erik [Division of Neurodegeneration, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Stockholm (Sweden); Baumann, Marc [Protein Chemistry Unit, Institute of Biomedicine/Anatomy, University of Helsinki, Helsinki (Finland); Poyhonen, Minna [Department of Clinical Genetics, Helsinki University Hospital, HUSLAB, Helsinki (Finland); Tikka, Saara [Protein Chemistry Unit, Institute of Biomedicine/Anatomy, University of Helsinki, Helsinki (Finland); Behbahani, Homira, E-mail: homira.behbahani@ki.se [Division of Clinical Geriatrics, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Stockholm (Sweden); Karolinska Institutet Alzheimer' s Disease Research Center, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Stockholm (Sweden)

    2013-02-01

    Cerebral Autosomal Dominant Arteriopathy with Subcortical Infarcts and Leukoencephalopathy (CADASIL) is a familiar fatal progressive degenerative disorder characterized by cognitive decline, and recurrent stroke in young adults. Pathological features include a dramatic reduction of brain vascular smooth muscle cells and severe arteriopathy with the presence of granular osmophilic material in the arterial walls. Here we have investigated the cellular and mitochondrial function in vascular smooth muscle cell lines (VSMCs) established from CADASIL mutation carriers (R133C) and healthy controls. We found significantly lower proliferation rates in CADASIL VSMC as compared to VSMC from controls. Cultured CADASIL VSMCs were not more vulnerable than control cells to a number of toxic substances. Morphological studies showed reduced mitochondrial connectivity and increased number of mitochondria in CADASIL VSMCs. Transmission electron microscopy analysis demonstrated increased irregular and abnormal mitochondria in CADASIL VSMCs. Measurements of mitochondrial membrane potential (Δψ{sub m}) showed a lower percentage of fully functional mitochondria in CADASIL VSMCs. For a number of genes previously reported to be changed in CADASIL VSMCs, immunoblotting analysis demonstrated a significantly reduced SOD1 expression. These findings suggest that alteration of proliferation and mitochondrial function in CADASIL VSMCs might have an effect on vital cellular functions important for CADASIL pathology. -- Highlights: ► CADASIL is an inherited disease of cerebral vascular cells. ► Mitochondrial dysfunction has been implicated in the pathogenesis of CADASIL. ► Lower proliferation rates in CADASIL VSMC. ► Increased irregular and abnormal mitochondria and lower mitochondrial membrane potential in CADASIL VSMCs. ► Reduced mitochondrial connectivity and increased number of mitochondria in CADASIL VSMCs.

  12. Analysis for apoptosis and necrosis on adipocytes, stromal vascular fraction, and adipose-derived stem cells in human lipoaspirates after liposuction.

    Science.gov (United States)

    Wang, Wei Z; Fang, Xin-Hua; Williams, Shelley J; Stephenson, Linda L; Baynosa, Richard C; Wong, Nancy; Khiabani, Kayvan T; Zamboni, William A

    2013-01-01

    Adipose-derived stem cells have become the most studied adult stem cells. The authors examined the apoptosis and necrosis rates for adipocyte, stromal vascular fraction, and adipose-derived stem cells in fresh human lipoaspirates. Human lipoaspirate (n = 8) was harvested using a standard liposuction technique. Stromal vascular fraction cells were separated from adipocytes and cultured to obtain purified adipose-derived stem cells. A panel of stem cell markers was used to identify the surface phenotypes of cultured adipose-derived stem cells. Three distinct stem cell subpopulations (CD90/CD45, CD105/CD45, and CD34/CD31) were selected from the stromal vascular fraction. Apoptosis and necrosis were determined by annexin V/propidium iodide assay and analyzed by flow cytometry. The cultured adipose-derived stem cells demonstrated long-term proliferation and differentiation evidenced by cell doubling time and positive staining with oil red O and alkaline phosphatase. Isolated from lipoaspirates, adipocytes exhibited 19.7 ± 3.7 percent apoptosis and 1.1 ± 0.3 percent necrosis; stromal vascular fraction cells revealed 22.0 ± 6.3 percent of apoptosis and 11.2 ± 1.9 percent of necrosis; stromal vascular fraction cells had a higher rate of necrosis than adipocytes (p vascular fraction cells, 51.1 ± 3.7 percent expressed CD90/CD45, 7.5 ± 1.0 percent expressed CD105/CD45, and 26.4 ± 3.8 percent expressed CD34/CD31. CD34/CD31 adipose-derived stem cells had lower rates of apoptosis and necrosis compared with CD105/CD45 adipose-derived stem cells (p necrosis than adipocytes. However, the extent of apoptosis and necrosis was significantly different among adipose-derived stem cell subpopulations.

  13. Advanced glycation end-products (AGEs acutely impair Ca2+ signalling in bovine aortic endothelial cells

    Directory of Open Access Journals (Sweden)

    Nadim eNaser

    2013-03-01

    Full Text Available Post-translational modification of proteins in diabetes, including formation of advanced glycation end products (AGEs are believed to contribute to vascular dysfunction and disease. Impaired function of the endothelium is an early indicator of vascular dysfunction in diabetes and as many endothelial cell processes are dependent upon intracellular [Ca2+] and Ca2+ signalling, the aim of this study was to examine the acute effects of AGEs on Ca2+ signalling in bovine aortic endothelial cells (BAEC. Ca2+ signalling was studied using the fluorescent indicator dye Fura2-AM. AGEs were generated by incubating bovine serum albumin with 0 - 250 mM glucose or glucose-6-phosphate for 0 to 120 days at 37ºC. Under all conditions, the main AGE species generated was carboxymethyl lysine (CML as assayed using both GC-MS and HPLC. In Ca2+-replete solution, exposure of BAEC to AGEs for 5 min caused an elevation in basal [Ca2+] and attenuated the increase in intracellular [Ca2+] caused by ATP (100 µM. In the absence of extracellular Ca2+, exposure of BAEC to AGEs for 5 min caused an elevation in basal [Ca2+] and attenuated subsequent intracellular Ca2+ release caused by ATP, thapsigargin (0.1 µM and ionomycin (3 µM, but AGEs did not affect extracellular Ca2+ entry induced by the re-addition of Ca2+ to the bathing solution in the presence of any of these agents. The anti-oxidant α-lipoic acid (2 µM and NAD(PH oxidase inhibitors apocynin (500 µM and diphenyleneiodonium (DPI, 1 µM abolished these effects of AGEs on BAECs, as did the IP3 receptor antagonist xestospongin C (1 µM. In summary, AGEs caused an acute depletion of Ca2+ from the intracellular store in BAECs, such that the Ca2+ signal stimulated by the subsequent application other agents acting upon this store is reduced. The mechanism may involve generation of ROS from NAD(PH oxidase and possible activation of the IP3 receptor.

  14. Endothelium derived nitric oxide synthase negatively regulates the PDGF-survivin pathway during flow-dependent vascular remodeling.

    Directory of Open Access Journals (Sweden)

    Jun Yu

    Full Text Available Chronic alterations in blood flow initiate structural changes in vessel lumen caliber to normalize shear stress. The loss of endothelial derived nitric oxide synthase (eNOS in mice promotes abnormal flow dependent vascular remodeling, thus uncoupling mechanotransduction from adaptive vascular remodeling. However, the mechanisms of how the loss of eNOS promotes abnormal remodeling are not known. Here we show that abnormal flow-dependent remodeling in eNOS knockout mice (eNOS (-/- is associated with activation of the platelet derived growth factor (PDGF signaling pathway leading to the induction of the inhibitor of apoptosis, survivin. Interfering with PDGF signaling or survivin function corrects the abnormal remodeling seen in eNOS (-/- mice. Moreover, nitric oxide (NO negatively regulates PDGF driven survivin expression and cellular proliferation in cultured vascular smooth muscle cells. Collectively, our data suggests that eNOS negatively regulates the PDGF-survivin axis to maintain proportional flow-dependent luminal remodeling and vascular quiescence.

  15. LRP1 in brain vascular smooth muscle cells mediates local clearance of Alzheimer's amyloid-β.

    Science.gov (United States)

    Kanekiyo, Takahisa; Liu, Chia-Chen; Shinohara, Mitsuru; Li, Jie; Bu, Guojun

    2012-11-14

    Impaired clearance of amyloid-β (Aβ) is a major pathogenic event for Alzheimer's disease (AD). Aβ depositions in brain parenchyma as senile plaques and along cerebrovasculature as cerebral amyloid angiopathy (CAA) are hallmarks of AD. A major pathway that mediates brain Aβ clearance is the cerebrovascular system where Aβ is eliminated through the blood-brain barrier (BBB) and/or degraded by cerebrovascular cells along the interstitial fluid drainage pathway. An Aβ clearance receptor, the low-density lipoprotein receptor-related protein 1 (LRP1), is abundantly expressed in cerebrovasculature, in particular in vascular smooth muscle cells. Previous studies have indicated a role of LRP1 in endothelial cells in transcytosing Aβ out of the brain across the BBB; however, whether this represents a significant pathway for brain Aβ clearance remains controversial. Here, we demonstrate that Aβ can be cleared locally in the cerebrovasculature by an LRP1-dependent endocytic pathway in smooth muscle cells. The uptake and degradation of both endogenous and exogenous Aβ were significantly reduced in LRP1-suppressed human brain vascular smooth muscle cells. Conditional deletion of Lrp1 in vascular smooth muscle cell in amyloid model APP/PS1 mice accelerated brain Aβ accumulation and exacerbated Aβ deposition as amyloid plaques and CAA without affecting Aβ production. Our results demonstrate that LRP1 is a major Aβ clearance receptor in cerebral vascular smooth muscle cell and a disturbance of this pathway contributes to Aβ accumulation. These studies establish critical functions of the cerebrovasculature system in Aβ metabolism and identify a new pathway involved in the pathogenesis of both AD and CAA.

  16. Hypoxia Inducible Factor Signaling and Experimental Persistent Pulmonary Hypertension of the Newborn: A Therapeutic Opportunity

    Directory of Open Access Journals (Sweden)

    Stephen eWedgwood

    2015-03-01

    Full Text Available BACKGROUND: Mitochondrial reactive oxygen species levels and nuclear factor kappa-light-chain-enhancer of activated B cells (NFκB activity are increased in a lamb model of persistent pulmonary hypertension of the newborn (PPHN. These events can trigger hypoxia inducible factor (HIF signaling in response to hypoxia, which has been shown to contribute to pulmonary vascular remodeling in rodent models of pulmonary hypertension. However the role of HIF signaling in chronic intrauterine pulmonary hypertension is not well understood.AIM: To determine if HIF signaling is increased in the lamb model of PPHN, and to identify the underlying mechanisms. RESULTS: PPHN was induced in lambs by antenatal ligation of the ductus arteriosus at 128 days gestation. After 9 days, lungs and pulmonary artery smooth muscle cells (PASMC were isolated from control and PPHN lambs. HIF-1α expression was increased in PPHN lungs and HIF activity was increased in PPHN PASMC relative to controls. Hypoxia increased HIF activity to a greater degree in PPHN vs. control PASMC. Control PASMC were exposed to cyclic stretch at 1Hz and 15% elongation for 24h, as an in vitro model of vascular stress. Stretch increased HIF activity, which was attenuated by inhibition of mitochondrial complex III and NFκB.CONCLUSION: Increased HIF signaling in PPHN is triggered by stretch, via mechanisms involving mitochondrial ROS and NFκB. Hypoxia substantially amplifies HIF activity in PPHN vascular cells. Targeting these signaling molecules may attenuate and reverse pulmonary vascular remodeling associated with PPHN.

  17. Atherosclerosis is a vascular stem cell disease caused by insulin.

    Science.gov (United States)

    Traunmüller, Friederike

    2018-07-01

    The present article proposes the hypothesis that when multipotent vascular stem cells are exposed to excessive insulin in a rhythmic pattern of sharply rising and falling concentrations, their differentiation is misdirected toward adipogenic and osteogenic cell lineages. This results in plaque-like accumulation of adipocytes with fat and cholesterol deposition from adipocyte debris, and osteogenic (progenitor) cells with a calcified matrix in advanced lesions. The ingrowth of capillaries and infiltration with macrophages, which upon uptake of lipids turn into foam cells, are unspecific pro-resolving reactions. Epidemiological, histopathological, pharmacological, and experimental evidence in favour of this hypothesis is summarised. Copyright © 2018. Published by Elsevier Ltd.

  18. Orphan Nuclear Receptor Nur77 Is a Novel Negative Regulator of Endothelin-1 Expression In Vascular Endothelial Cells

    OpenAIRE

    Qin, Qing; Chen, Ming; Yi, Bing; You, Xiaohua; Yang, Ping; Sun, Jianxin

    2014-01-01

    Endothelin-1 (ET-1) produced by vascular endothelial cells plays essential roles in the regulation of vascular tone and development of cardiovascular diseases. The objective of this study is to identify novel regulators implicated in the regulation of ET-1 expression in vascular endothelial cells (ECs). By using quantitative real-time PCR (qRT-PCR) and Enzyme-linked immunosorbent assay (ELISA), we show that either ectopic expression of orphan nuclear receptor Nur77 or pharmacological activati...

  19. NUTRITION AND VASCULAR SUPPLY OF RETINAL GANGLION CELLS DURING HUMAN DEVELOPMENT

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    Paul eRutkowski

    2016-04-01

    Full Text Available Purpose. To review the roles of the different vascular beds nourishing the inner retina (retinal ganglion cells during normal development of the human eye and using our own tissue specimens to support our conclusions.Methods. An extensive search of the appropriate literature included PubMed, Google scholar, and numerous available textbooks. In addition, choroidal and retinal NADPH-diaphorase stained whole mount preparations were investigated.Results. The first critical interaction between vascular bed and retinal ganglion cell (RGC formation occurs in the 6th-8th month of gestation leading to a massive reduction of RGCs mainly in the peripheral retina. The first three years of age are characterized by an intense growth of the eyeball to near adult size. In the adult eye, the influence of the choroid on inner retinal nutrition was determined by examining the peripheral retinal watershed zones in more detail.Conclusion. This delicately balanced situation of retinal ganglion cell nutrition is described in the different regions of the eye, and a new graphic presentation is introduced to combine morphological measurements and clinical visual field data.

  20. Bosutinib, dasatinib, imatinib, nilotinib, and ponatinib differentially affect the vascular molecular pathways and functionality of human endothelial cells.

    Science.gov (United States)

    Gover-Proaktor, Ayala; Granot, Galit; Pasmanik-Chor, Metsada; Pasvolsky, Oren; Shapira, Saar; Raz, Oshrat; Raanani, Pia; Leader, Avi

    2018-05-09

    The tyrosine kinase inhibitors (TKIs), nilotinib, ponatinib, and dasatinib (but not bosutinib or imatinib), are associated with vascular adverse events (VAEs) in chronic myeloid leukemia (CML). Though the mechanism is inadequately understood, an effect on vascular cells has been suggested. We investigated the effect of imatinib, nilotinib, dasatinib, bosutinib, and ponatinib on tube formation, cell viability, and gene expression of human vascular endothelial cells (HUVECs). We found a distinct genetic profile in HUVECs treated with dasatinib, ponatinib, and nilotinib compared to bosutinib and imatinib, who resembled untreated samples. However, unique gene expression and molecular pathway alterations were detected between dasatinib, ponatinib, and nilotinib. Angiogenesis/blood vessel-related pathways and HUVEC function (tube formation/viability) were adversely affected by dasatinib, ponatinib, and nilotinib but not by imatinib or bosutinib. These results correspond to the differences in VAE profiles of these TKIs, support a direct effect on vascular cells, and provide direction for future research.

  1. Vascular Endothelial Growth Factor and Angiopoietin-1 Stimulate Postnatal Hematopoiesis by Recruitment of Vasculogenic and Hematopoietic Stem Cells

    Science.gov (United States)

    Hattori, Koichi; Dias, Sergio; Heissig, Beate; Hackett, Neil R.; Lyden, David; Tateno, Masatoshi; Hicklin, Daniel J.; Zhu, Zhenping; Witte, Larry; Crystal, Ronald G.; Moore, Malcolm A.S.; Rafii, Shahin

    2001-01-01

    Tyrosine kinase receptors for angiogenic factors vascular endothelial growth factor (VEGF) and angiopoietin-1 (Ang-1) are expressed not only by endothelial cells but also by subsets of hematopoietic stem cells (HSCs). To further define their role in the regulation of postnatal hematopoiesis and vasculogenesis, VEGF and Ang-1 plasma levels were elevated by injecting recombinant protein or adenoviral vectors expressing soluble VEGF165, matrix-bound VEGF189, or Ang-1 into mice. VEGF165, but not VEGF189, induced a rapid mobilization of HSCs and VEGF receptor (VEGFR)2+ circulating endothelial precursor cells (CEPs). In contrast, Ang-1 induced delayed mobilization of CEPs and HSCs. Combined sustained elevation of Ang-1 and VEGF165 was associated with an induction of hematopoiesis and increased marrow cellularity followed by proliferation of capillaries and expansion of sinusoidal space. Concomitant to this vascular remodeling, there was a transient depletion of hematopoietic activity in the marrow, which was compensated by an increase in mobilization and recruitment of HSCs and CEPs to the spleen resulting in splenomegaly. Neutralizing monoclonal antibody to VEGFR2 completely inhibited VEGF165, but not Ang-1–induced mobilization and splenomegaly. These data suggest that temporal and regional activation of VEGF/VEGFR2 and Ang-1/Tie-2 signaling pathways are critical for mobilization and recruitment of HSCs and CEPs and may play a role in the physiology of postnatal angiogenesis and hematopoiesis. PMID:11342585

  2. Inhibition of Vascular Smooth Muscle Growth via Signaling Crosstalk between AMP-Activated Protein Kinase and cAMP-Dependent Protein Kinase

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    Joshua Daniel Stone

    2012-10-01

    Full Text Available Abnormal vascular smooth muscle (VSM growth is central in the pathophysiology of vascular disease yet fully effective therapies to curb this growth are lacking. Recent findings from our lab and others support growth control of VSM by adenosine monophosphate (AMP-based approaches including the metabolic sensor AMP-activated protein kinase (AMPK and cAMP-dependent protein kinase (PKA. Molecular crosstalk between AMPK and PKA has been previously suggested, yet the extent to which this occurs and its biological significance in VSM remains unclear. Considering their common AMP backbone and similar signaling characteristics, we hypothesized that crosstalk exists between AMPK and PKA in the regulation of VSM growth. Using rat primary VSM cells, the AMPK agonist AICAR increased AMPK activity and phosphorylation of the catalytic Thr172 site on AMPK. Interestingly, AICAR also phosphorylated a suspected PKA-inhibitory Ser485 site on AMPK, and these cumulative events were reversed by the PKA inhibitor PKI suggesting possible PKA-mediated regulation of AMPK. AICAR also increased PKA activity in a reversible fashion. The cAMP stimulator forskolin increased PKA activity and completely ameliorated Ser/Thr protein phosphatase-2C activity, suggesting a potential mechanism of AMPK modulation by PKA since inhibition of PKA by PKI reduced AMPK activity. Functionally, AMPK inhibited serum-stimulated cell cycle progression and cellular proliferation; however, PKA failed to do so. Moreover, AMPK and PKA reduced PDGF-β-stimulated VSM cell migration. Collectively, these results show that AMPK is capable of reducing VSM growth in both anti-proliferative and anti-migratory fashions. Furthermore, these data suggest that AMPK may be modulated by PKA and that positive feedback may exist between these two systems. These findings reveal a discrete nexus between AMPK and PKA in VSM and provide basis for metabolically-directed targets in reducing pathologic VSM growth.

  3. Ihh controls cartilage development by antagonizing Gli3, but requires additional effectors to regulate osteoblast and vascular development.

    Science.gov (United States)

    Hilton, Matthew J; Tu, Xiaolin; Cook, Julie; Hu, Hongliang; Long, Fanxin

    2005-10-01

    Indian hedgehog (Ihh) controls multiple aspects of endochondral skeletal development, including proliferation and maturation of chondrocytes, osteoblast development and cartilage vascularization. Although it is known that Gli transcription factors are key effectors of hedgehog signaling, it has not been established which Gli protein mediates Ihh activity in skeletal development. Here, we show that removal of Gli3 in Ihh-null mouse embryos restored normal proliferation and maturation of chondrocytes, but only partially rescued the defects in osteoblast development and cartilage vascularization. Remarkably, in both Ihh-/- and Ihh-/-; Gli3-/- embryos, vascularization promoted osteoblast development in perichondrial progenitor cells. Our results not only establish Gli3 as a critical effector for Ihh activity in the developing skeleton, but also identify an osteogenic role for a vasculature-derived signal, which integrates with Ihh and Wnt signals to determine the osteoblast versus chondrocyte fate in the mesenchymal progenitors.

  4. CRH promotes human colon cancer cell proliferation via IL-6/JAK2/STAT3 signaling pathway and VEGF-induced tumor angiogenesis.

    Science.gov (United States)

    Fang, Xianjun; Hong, Yali; Dai, Li; Qian, Yuanyuan; Zhu, Chao; Wu, Biao; Li, Shengnan

    2017-11-01

    Corticotrophin-releasing hormone (CRH) has been demonstrated to participate in various diseases. Our previous study showed that its receptor CRHR1 mediated the development of colitis-associated cancer in mouse model. However, the detailed mechanisms remain unclear. In this study, we explored the oncogenetic role of CRH/CRHR1 signaling in colon cancer cells. Cell proliferation and colony formation assays revealed that CRH contributed to cell proliferation. Moreover, tube formation assay showed that CRH-treated colon cancer cell supernatant significantly promoted tube formation of human umbilical vein endothelial cells (HUVECs). And these effects could be reversed by the CRHR1 specific antagonist Antalarmin. Further investigation showed that CRH significantly upregulated the expressions of interlukin-6 (IL-6) and vascular endothelial growth factor (VEGF) through activating nuclear factor-kappa B (NF-κB). The CRH-induced IL-6 promoted phosphorylation of janus kinase 2 (JAK2) and signal transducers and activators of transcription 3 (STAT3). STAT3 inhibition by Stattic significantly inhibited the CRH-induced cell proliferation. In addition, silence of VEGF resulted in declined tube formation induced by CRH. Taken together, CRH/CRHR1 signaling promoted human colon cancer cell proliferation via NF-κB/IL-6/JAK2/STAT3 signaling pathway and tumor angiogenesis via NF-κB/VEGF signaling pathway. Our results provide evidence to support a critical role for the CRH/CRHR1 signaling in colon cancer progression and suggest its potential utility as a new therapeutic target for colon cancer. © 2017 Wiley Periodicals, Inc.

  5. Inhibition of DNA methyltransferase induces G2 cell cycle arrest and apoptosis in human colorectal cancer cells via inhibition of JAK2/STAT3/STAT5 signalling.

    Science.gov (United States)

    Xiong, Hua; Chen, Zhao-Fei; Liang, Qin-Chuan; Du, Wan; Chen, Hui-Min; Su, Wen-Yu; Chen, Guo-Qiang; Han, Ze-Guang; Fang, Jing-Yuan

    2009-09-01

    DNA methyltransferase inhibitors (MTIs) have recently emerged as promising chemotherapeutic or preventive agents for cancer, despite their poorly characterized mechanisms of action. The present study shows that DNA methylation is integral to the regulation of SH2-containing protein tyrosine phosphatase 1 (SHP1) expression, but not for regulation of suppressors of cytokine signalling (SOCS)1 or SOCS3 in colorectal cancer (CRC) cells. SHP1 expression correlates with down-regulation of Janus kinase/signal transducers and activators of transcription (JAK2/STAT3/STAT5) signalling, which is mediated in part by tyrosine dephosphorylation events and modulation of the proteasome pathway. Up-regulation of SHP1 expression was achieved using a DNA MTI, 5-aza-2'-deoxycytidine (5-aza-dc), which also generated significant down-regulation of JAK2/STAT3/STAT5 signalling. We demonstrate that 5-aza-dc suppresses growth of CRC cells, and induces G2 cell cycle arrest and apoptosis through regulation of downstream targets of JAK2/STAT3/STAT5 signalling including Bcl-2, p16(ink4a), p21(waf1/cip1) and p27(kip1). Although 5-aza-dc did not significantly inhibit cell invasion, 5-aza-dc did down-regulate expression of focal adhesion kinase and vascular endothelial growth factor in CRC cells. Our results demonstrate that 5-aza-dc can induce SHP1 expression and inhibit JAK2/STAT3/STAT5 signalling. This study represents the first evidence towards establishing a mechanistic link between inhibition of JAK2/STAT3/STAT5 signalling and the anticancer action of 5-aza-dc in CRC cells that may lead to the use of MTIs as a therapeutic intervention for human colorectal cancer.

  6. Vascular endothelial growth factor C promotes cervical cancer cell invasiveness via regulation of microRNA-326/cortactin expression.

    Science.gov (United States)

    Cheng, Yang; Jiang, Shuyi; Yuan, Jin; Liu, Junxiu; Simoncini, Tommaso

    2018-04-16

    Vascular endothelial growth factor C (VEGF-C) accelerates cervical cancer metastasis, while the detailed mechanism remains largely unknown. Recent evidence indicates that microRNA play a crucial role in controlling cancer cell invasiveness. In the present study, we investigated the role of miR-326 in VEGF-C-induced cervical cancer cell invasion. VEGF-C expression was higher and miR-326 was much lower in primary cervical cancer specimens than that in non-cancerous specimens, and a negative correlation between VEGF-C and miR-326 was found. On cervical carcinoma cell line SiHa cells, treatment with VEGF-C downregulated miR-326 level and increased cortactin protein expression. Transfection with miR-326 mimic reversed cortactin expression induced by VEGF-C, suggesting that VEGF-C increased cortactin via downregulation of miR-326. VEGF-C activated c-Src and c-Src inhibitor PP2 abolished VEGF-C effect on miR-326 and cortactin expression, implying that VEGF-C regulated miR-326/cortactin via c-Src signaling. VEGF-C promoted SiHa cell invasion index, which was largely inhibited by transfection with miR-326 antagonist or by siRNA against cortactin. In conclusion, our findings implied that VEGF-C reduced miR-326 expression and increased cortactin expression through c-Src signaling, leading to enhanced cervical cancer invasiveness. This may shed light on potential therapeutic strategies for cervical cancer therapy.

  7. N-Acetylglucosamine Functions in Cell Signaling

    Directory of Open Access Journals (Sweden)

    James B. Konopka

    2012-01-01

    Full Text Available The amino sugar N-acetylglucosamine (GlcNAc is well known for the important structural roles that it plays at the cell surface. It is a key component of bacterial cell wall peptidoglycan, fungal cell wall chitin, and the extracellular matrix of animal cells. Interestingly, recent studies have also identified new roles for GlcNAc in cell signaling. For example, GlcNAc stimulates the human fungal pathogen Candida albicans to undergo changes in morphogenesis and expression of virulence genes. Pathogenic E. coli responds to GlcNAc by altering the expression of fimbriae and CURLI fibers that promote biofilm formation and GlcNAc stimulates soil bacteria to undergo changes in morphogenesis and production of antibiotics. Studies with animal cells have revealed that GlcNAc influences cell signaling through the posttranslational modification of proteins by glycosylation. O-linked attachment of GlcNAc to Ser and Thr residues regulates a variety of intracellular proteins, including transcription factors such as NFκB, c-myc, and p53. In addition, the specificity of Notch family receptors for different ligands is altered by GlcNAc attachment to fucose residues in the extracellular domain. GlcNAc also impacts signal transduction by altering the degree of branching of N-linked glycans, which influences cell surface signaling proteins. These emerging roles of GlcNAc as an activator and mediator of cellular signaling in fungi, animals, and bacteria will be the focus of this paper.

  8. Determinants of cell-to-cell variability in protein kinase signaling.

    Directory of Open Access Journals (Sweden)

    Matthias Jeschke

    Full Text Available Cells reliably sense environmental changes despite internal and external fluctuations, but the mechanisms underlying robustness remain unclear. We analyzed how fluctuations in signaling protein concentrations give rise to cell-to-cell variability in protein kinase signaling using analytical theory and numerical simulations. We characterized the dose-response behavior of signaling cascades by calculating the stimulus level at which a pathway responds ('pathway sensitivity' and the maximal activation level upon strong stimulation. Minimal kinase cascades with gradual dose-response behavior show strong variability, because the pathway sensitivity and the maximal activation level cannot be simultaneously invariant. Negative feedback regulation resolves this trade-off and coordinately reduces fluctuations in the pathway sensitivity and maximal activation. Feedbacks acting at different levels in the cascade control different aspects of the dose-response curve, thereby synergistically reducing the variability. We also investigated more complex, ultrasensitive signaling cascades capable of switch-like decision making, and found that these can be inherently robust to protein concentration fluctuations. We describe how the cell-to-cell variability of ultrasensitive signaling systems can be actively regulated, e.g., by altering the expression of phosphatase(s or by feedback/feedforward loops. Our calculations reveal that slow transcriptional negative feedback loops allow for variability suppression while maintaining switch-like decision making. Taken together, we describe design principles of signaling cascades that promote robustness. Our results may explain why certain signaling cascades like the yeast pheromone pathway show switch-like decision making with little cell-to-cell variability.

  9. Anti-atherosclerotic plants which modulate the phenotype of vascular smooth muscle cells.

    Science.gov (United States)

    Saleh Al-Shehabi, Tuqa; Iratni, Rabah; Eid, Ali H

    2016-10-15

    Cardiovascular disease (CVD) remains the leading cause of global death, with atherosclerosis being a major contributor to this mortality. Several mechanisms are implicated in the pathogenesis of this disease. A key element in the development and progression of atherosclerotic lesions is the phenotype of vascular smooth muscle cells. Under pathophysiologic conditions such as injury, these cells switch from a contractile to a synthetic phenotype that often possesses high proliferative and migratory capacities. Despite major advances made in the management and treatment of atherosclerosis, mortality associated with this disease remains high. This mandates that other approaches be sought. Herbal medicine, especially for the treatment of CVD, has been gaining more attention in recent years. This is in no small part due to the evidence-based values associated with the consumption of many plants as well as the relatively cheaper prices, easier access and conventional folk medicine "inherited" over generations. Sections: In this review, we provide a brief introduction about the pathogenesis of atherosclerosis then we highlight the role of vascular smooth muscle cells in this disease, especially when a phenotypic switch of these cells arises. We then thoroughly discuss the various plants that show potentially beneficial effects as anti-atherosclerotic, with prime attention given to herbs and plants that inhibit the phenotypic switch of vascular smooth muscle cells. Accumulating evidence provides the justification for the use of botanicals in the treatment or prevention of atherosclerosis. However, further studies, especially clinical ones, are warranted to better define several pharmacological parameters of these herbs, such as toxicity, tolerability, and efficacy. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. Additive effects of low concentrations of estradiol-17β and progesterone on nitric oxide production by human vascular endothelial cells through shared signaling pathways.

    Science.gov (United States)

    Pang, Yefei; Thomas, Peter

    2017-01-01

    Potential cardiovascular benefits of low-dose formulations of estrogens and progesterone (P4) for treating climacteric symptoms in postmenopausal women remain unclear because information is lacking on their combined vascular effects. Protective effects of low concentrations (5nM) of P4 and estradiol-17β (E2), alone and in combination (P4+E2), were investigated in a nongenomic model of vascular protection which measured acute increases in nitric oxide (NO) production by cultured human umbilical vein endothelial cells (HUVECs). Treatment with 5nM P4+E2 for twenty minutes significantly increased NO production and endothelial NO synthase (eNOS) phosphorylation, whereas 5nM treatments with either steroid alone were ineffective. The 5nM P4+E2 treatment also increased phosphorylation of ERK and Akt, mimicking the effects of higher concentrations of P4 and E2 alone. Pre-treatment with inhibitors of PI3K (wortmannin), Akt (ML-9), and MAP kinase (AZD6244 and U0126) completely blocked the NO response to 5nM P4+E2. Combined 5nM treatments with specific estrogen and progesterone receptor agonists showed an involvement of membrane progesterone receptor alpha (mPRα, also known as PAQR7), G protein-coupled estrogen receptor 1 (GPER), and estrogen receptor alpha (ERα), but not ERβ, in P4+E2 stimulation of NO production. P4+E2 also exerted genomic actions, increasing mPRα, GPER, cyclooxygenase-1, and prostacyclin-synthase mRNA levels. Taken together, the results show that a low concentration of P4+E2 rapidly increases NO production in HUVECs through mPRα, ERα, and GPER and involves common signaling pathways, PI3K/Akt and MAP kinase. These in vitro findings suggest that low doses of E2 and P4 may also have some beneficial cardiovascular effects in vivo when administered as hormone replacement therapy (HRT) for post-menopausal women. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. Gremlin promotes retinal pigmentation epithelial (RPE) cell proliferation, migration and VEGF production via activating VEGFR2-Akt-mTORC2 signaling.

    Science.gov (United States)

    Liu, Yuan; Chen, Zhijun; Cheng, Haixia; Chen, Juan; Qian, Jing

    2017-01-03

    Retinopathy of prematurity (ROP) is characterized by late-phase pathologic retinal vasoproliferation. Gremlin is a novel vascular endothelial growth factors (VEGF) receptor 2 (VEGFR2) agonist and promotes angiogenic response. We demonstrated that gremlin expression was significantly increased in retinas of ROP model mice, which was correlated with VEGF upregulation. In retinal pigmentation epithelial (RPE) cells, gremlin activated VEGFR2-Akt-mTORC2 (mammalian target of rapamycin complex 2) signaling, and promoted cell proliferation, migration and VEGF production. VEGFR inhibition (by SU5416) or shRNA knockdown almost abolished gremlin-mediated pleiotropic functions in RPE cells. Further, pharmacological inhibition of Akt-mTOR, or shRNA knockdown of key mTORC2 component (Rictor or Sin1) also attenuated gremlin-exerted activities in RPE cells. We conclude that gremlin promotes RPE cell proliferation, migration and VEGF production possibly via activating VEGFR2-Akt-mTORC2 signaling. Gremlin could be a novel therapeutic target of ROP or other retinal vasoproliferation diseases.

  12. PolNet: A Tool to Quantify Network-Level Cell Polarity and Blood Flow in Vascular Remodeling.

    Science.gov (United States)

    Bernabeu, Miguel O; Jones, Martin L; Nash, Rupert W; Pezzarossa, Anna; Coveney, Peter V; Gerhardt, Holger; Franco, Claudio A

    2018-05-08

    In this article, we present PolNet, an open-source software tool for the study of blood flow and cell-level biological activity during vessel morphogenesis. We provide an image acquisition, segmentation, and analysis protocol to quantify endothelial cell polarity in entire in vivo vascular networks. In combination, we use computational fluid dynamics to characterize the hemodynamics of the vascular networks under study. The tool enables, to our knowledge for the first time, a network-level analysis of polarity and flow for individual endothelial cells. To date, PolNet has proven invaluable for the study of endothelial cell polarization and migration during vascular patterning, as demonstrated by two recent publications. Additionally, the tool can be easily extended to correlate blood flow with other experimental observations at the cellular/molecular level. We release the source code of our tool under the Lesser General Public License. Copyright © 2018 Biophysical Society. Published by Elsevier Inc. All rights reserved.

  13. Invasion of vascular cells in vitro by Porphyromonas endodontalis.

    Science.gov (United States)

    Dorn, B R; Harris, L J; Wujick, C T; Vertucci, F J; Progulske-Fox, A

    2002-04-01

    The objective of this study was to determine whether laboratory strains and clinical isolates of microorganisms associated with root canal infections can invade primary cultures of cardiovascular cells. Quantitative levels of bacterial invasion of human coronary artery endothelial cells (HCAEC) and coronary artery smooth muscle cells (CASMC) were measured using a standard antibiotic protection assay. Transmission electron microscopy was used to confirm and visualize internalization within the vascular cells. Of the laboratory and clinical strains tested, only P. endodontalis ATCC 35406 was invasive in an antibiotic protection assay using HCAEC and CASMC. Invasion of P. endodontalis ATCC 35406 was confirmed by transmission electron microscopy. Certain microorganisms associated with endodontic infections are invasive. If bacterial invasion of the vasculature contributes to the pathogenesis of cardiovascular disease, then microorganisms in the pulp chamber represent potential pathogens.

  14. Lipid rafts and B cell signaling.

    Science.gov (United States)

    Gupta, Neetu; DeFranco, Anthony L

    2007-10-01

    B cells comprise an essential component of the humoral immune system. They are equipped with the unique ability to synthesize and secrete pathogen-neutralizing antibodies, and share with professional antigen presenting cells the ability to internalize foreign antigens, and process them for presentation to helper T cells. Recent evidence indicates that specialized cholesterol- and glycosphingolipid-rich microdomains in the plasma membrane commonly referred to as lipid rafts, serve to compartmentalize key signaling molecules during the different stages of B cell activation including B cell antigen receptor (BCR)-initiated signal transduction, endocytosis of BCR-antigen complexes, loading of antigenic peptides onto MHC class II molecules, MHC-II associated antigen presentation to helper T cells, and receipt of helper signals via the CD40 receptor. Here we review the recent literature arguing for a role of lipid rafts in the spatial organization of B cell function.

  15. Vitamin K2 inhibits rat vascular smooth muscle cell calcification by restoring the Gas6/Axl/Akt anti-apoptotic pathway.

    Science.gov (United States)

    Qiu, Cuiting; Zheng, Haijun; Tao, Huiren; Yu, Wenjun; Jiang, Xiaoyu; Li, Aiqin; Jin, Hui; Lv, Anlin; Li, Huan

    2017-09-01

    Vascular calcification is associated with cardiovascular disease as a complication of hypertension, hyperlipidemia, diabetes mellitus, and chronic kidney disease. Vitamin K2 (VK2) delays vascular calcification by an unclear mechanism. Moreover, apoptosis modulates vascular smooth muscle cell (VSMC) calcification. This paper aimed to study VK2-modified VSMC calcification and survival cell signaling mediated by growth arrest-specific gene 6 (Gas6) and its tyrosine kinase receptor Axl. Primary-cultured VSMCs were dose-dependently treated with VK2 in the presence of calcification medium for 8 days, or pre-treated for 1 h with/without the Axl inhibitor R428 (2 μmol/L) or the caspase inhibitor Z-VAD-fmk (20 μmol/L) followed by treatment with VK2 (10 μmol/L) or rmGas6 (200 nmol/L) in calcification medium for 8 days. Calcium deposition was determined by the o-cresolphthalein complexone assay and Alizarin Red S staining. Apoptosis was determined by TUNEL and flow cytometry using Annexin V-FITC and propidium iodide staining. Western blotting detected the expressions of Axl, Gas6, p-Akt, Akt, and Bcl2. VK2 significantly inhibited CaCl 2 - and β-sodium glycerophosphate (β-GP)-induced VSMC calcification and apoptosis, which was dependent on restored Gas6 expression and activated downstream signaling by Axl, p-Akt, and Bcl2. Z-VAD-fmk significantly inhibited CaCl 2 - and β-GP-induced VSMC calcification and apoptosis. Augmented recombinant mouse Gas6 protein (rmGas6) expression significantly reduced VSMC calcification and apoptosis. Furthermore, the Gas6/Axl interaction was inhibited by R428, which abolished the preventive effect of VK2 on CaCl 2 - and β-GP-induced apoptosis and calcification. These results suggest that Gas6 is critical in VK2-mediated functions that attenuate CaCl 2 - and β-GP-induced VSMC calcification by blocking apoptosis.

  16. Effect of bFGF on radiation-induced apoptosis of vascular endothelial cells

    International Nuclear Information System (INIS)

    Gu Qingyang; Wang Dewen; Li Yuejuan; Peng Ruiyun; Dong Bo; Wang Zhaohai; Liu Jie; Deng Hua; Jiang Tao

    2003-01-01

    Objective: To study the effect of bFGF on radiation-induced apoptosis vascular endothelial cells. Methods: A cell line PAE (porcine aortic endothelial cells) and primary cultured HUVEC (human umbilical vein endothelial cells) were irradiated with 60 Co γ-rays to establish cell apoptosis models. Flow cytometry with annexin-V-FITC + PI labeling was used to evaluate cell apoptosis. Different amounts of bFGF were used to study their effects on radiation-induced endothelial cell apoptosis. Results and Conclusions: It is found that bFGF could inhibit radiation-induced endothelial cell apoptosis in a considerable degree

  17. Glutathione regulation of redox-sensitive signals in tumor necrosis factor-α-induced vascular endothelial dysfunction

    International Nuclear Information System (INIS)

    Tsou, T.-C.; Yeh, S.C.; Tsai, F.-Y.; Chen, J.-W.; Chiang, H.-C.

    2007-01-01

    We investigated the regulatory role of glutathione in tumor necrosis factor-alpha (TNF-α)-induced vascular endothelial dysfunction as evaluated by using vascular endothelial adhesion molecule expression and monocyte-endothelial monolayer binding. Since TNF-α induces various biological effects on vascular cells, TNF-α dosage could be a determinant factor directing vascular cells into different biological fates. Based on the adhesion molecule expression patterns responding to different TNF-α concentrations, we adopted the lower TNF-α (0.2 ng/ml) to rule out the possible involvement of other TNF-α-induced biological effects. Inhibition of glutathione synthesis by L-buthionine-(S,R)-sulfoximine (BSO) resulted in down-regulations of the TNF-α-induced adhesion molecule expression and monocyte-endothelial monolayer binding. BSO attenuated the TNF-α-induced nuclear factor-kappaB (NF-κB) activation, however, with no detectable effect on AP-1 and its related mitogen-activated protein kinases (MAPKs). Deletion of an AP-1 binding site in intercellular adhesion molecule-1 (ICAM-1) promoter totally abolished its constitutive promoter activity and its responsiveness to TNF-α. Inhibition of ERK, JNK, or NF-κB attenuates TNF-α-induced ICAM-1 promoter activation and monocyte-endothelial monolayer binding. Our study indicates that TNF-α induces adhesion molecule expression and monocyte-endothelial monolayer binding mainly via activation of NF-κB in a glutathione-sensitive manner. We also demonstrated that intracellular glutathione does not modulate the activation of MAPKs and/or their downstream AP-1 induced by lower TNF-α. Although AP-1 activation by the lower TNF-α was not detected in our systems, we could not rule out the possible involvement of transiently activated MAPKs/AP-1 in the regulation of TNF-α-induced adhesion molecule expression

  18. Vascular lumen formation.

    Science.gov (United States)

    Lammert, Eckhard; Axnick, Jennifer

    2012-04-01

    The vascular system developed early in evolution. It is required in large multicellular organisms for the transport of nutrients, oxygen, and waste products to and from tissues. The vascular system is composed of hollow tubes, which have a high level of complexity in vertebrates. Vasculogenesis describes the de novo formation of blood vessels, e.g., aorta formation in vertebrate embryogenesis. In contrast, angiogenesis is the formation of blood vessels from preexisting ones, e.g., sprouting of intersomitic blood vessels from the aorta. Importantly, the lumen of all blood vessels in vertebrates is lined and formed by endothelial cells. In both vasculogenesis and angiogenesis, lumen formation takes place in a cord of endothelial cells. It involves a complex molecular mechanism composed of endothelial cell repulsion at the cell-cell contacts within the endothelial cell cords, junctional rearrangement, and endothelial cell shape change. As the vascular system also participates in the course of many diseases, such as cancer, stroke, and myocardial infarction, it is important to understand and make use of the molecular mechanisms of blood vessel formation to better understand and manipulate the pathomechanisms involved.

  19. CD4+ T Cell Activation and Vascular Normalization: Two Sides of the Same Coin?

    Science.gov (United States)

    De Palma, Michele; Jain, Rakesh K

    2017-05-16

    Normalization of tumor blood vessels enhances the infiltration and functions of T cells. Tian et al. (2017) report that effector CD4 + T cells, in turn, support vascular normalization, highlighting intertwined roles for blood vessels and T cells in cancer. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Red cell 2, 3-diphosphoglycerate levels among diabetic patents with and without vascular complications.

    Science.gov (United States)

    Kanter, Y; Bessman, S P; Bessman, A

    1975-08-01

    There have been differences of opinion among authors concening in the levels of red cell 2,3-diphosphoglycerate (2,3-DPG) and nucleotides in nonacidotic diabetic patients. Our data suggest that abnormal levels of 2, 3-DPG in diabetic patients are related to the presence of vascular complications and not to the duration of the disease per sec. 2,3-DPG levels are normal in diabetic patients with no evidence of vascular complications (group A). In ambulatory patients with vascular complications (group B), significantly higher levels of 2,3-DPG are found than in normal subjects and patients in group A. In hospitalized diabetic patients with active peripheral vascular complications (group C), levels of 2,3-DPG are likewise significantly increased over those of normal subjects and patients of group A. 2,3-DPG was found to be significantly elevated in patients of group C as compared with group B. 2,3-DPG levels in venous blood from infected legs as compared with those of the peripheral venous blood were not significantly different, thereby ruling out local factors. There were no differences in the blood lactate levels in any of the group studied. The elevation of the 2,3-DPG levels may be a reflection of attempted red blood cell compensation for tissue hypoxia in the diabetic with vascular disease.

  1. CD147 induces up-regulation of vascular endothelial growth factor in U937-derived foam cells through PI3K/AKT pathway.

    Science.gov (United States)

    Zong, JiaXin; Li, YunTian; Du, DaYong; Liu, Yang; Yin, YongJun

    2016-11-01

    Intraplaque angiogenesis has been recognized as an important risk factor for the rupture of advanced atherosclerotic plaques in recent years. CD147, also called Extracellular Matrix Metalloproteinase Inducer, has been found the ability to promote angiogenesis in many pathological conditions such as cancer diseases and rheumatoid arthritis via the up-regulation of vascular endothelial growth factor (VEGF), a critical mediator of angiogenesis. We investigated whether CD147 would also induce the up-regulation of VEGF in the foam cells formation process and explored the probable signaling pathway. The results showed the expression of CD147 and VEGF was significantly higher in U937-derived foam cells. After CD147 stealth siRNA transfection treatment, the production of VEGF was reduced depended on the inhibition efficiency of CD147 siRNAs.The special signaling pathway inhibitors LY294002, SP600125, SB203580 and U0126 were added to cultures respectively and the results showed LY294002 dose-dependently inhibited the expression of VEGF. The reduction of phospho-Akt was observed in both LY294002 and siRNA groups, suggested that the phosphatidylinositol 3-kinase/Akt pathway may be the probable signaling pathway underlying CD147 induced up-regulation of VEGF in U937-derived foam cells. Copyright © 2016 Elsevier Inc. All rights reserved.

  2. NF-kappaB signaling mediates vascular smooth muscle endothelin type B receptor expression in resistance arteries

    DEFF Research Database (Denmark)

    Zheng, Jian-Pu; Zhang, Yaping; Edvinsson, Lars

    2010-01-01

    Vascular smooth muscle cells (SMC) endothelin type B (ET(B)) receptor upregulation results in strong vasoconstriction and reduction of local blood flow. We hypothesizes that the underlying molecular mechanisms involve transcriptional factor nuclear factor-kappaB (NF-kappaB) pathway. ET(B) recepto...

  3. Additive Manufacturing of Vascular Grafts and Vascularized Tissue Constructs.

    Science.gov (United States)

    Elomaa, Laura; Yang, Yunzhi Peter

    2017-10-01

    There is a great need for engineered vascular grafts among patients with cardiovascular diseases who are in need of bypass therapy and lack autologous healthy blood vessels. In addition, because of the severe worldwide shortage of organ donors, there is an increasing need for engineered vascularized tissue constructs as an alternative to organ transplants. Additive manufacturing (AM) offers great advantages and flexibility of fabrication of cell-laden, multimaterial, and anatomically shaped vascular grafts and vascularized tissue constructs. Various inkjet-, extrusion-, and photocrosslinking-based AM techniques have been applied to the fabrication of both self-standing vascular grafts and porous, vascularized tissue constructs. This review discusses the state-of-the-art research on the use of AM for vascular applications and the key criteria for biomaterials in the AM of both acellular and cellular constructs. We envision that new smart printing materials that can adapt to their environment and encourage rapid endothelialization and remodeling will be the key factor in the future for the successful AM of personalized and dynamic vascular tissue applications.

  4. Anti-vascular agent Combretastatin A-4-P modulates Hypoxia Inducible Factor-1 and gene expression

    Directory of Open Access Journals (Sweden)

    Currie Margaret J

    2006-12-01

    Full Text Available Abstract Background A functional vascular network is essential for the survival, growth and spread of solid tumours, making blood vessels a key target for therapeutic strategies. Combretastatin A-4 phosphate (CA-4-P is a tubulin-depolymerising agent in Phase II clinical trials as a vascular disrupting agent. Not much is known of the molecular effect of CA-4-P under tumour conditions. The tumour microenvironment differs markedly from that in normal tissue, specifically with respect to oxygenation (hypoxia. Gene regulation under tumour conditions is governed by hypoxia inducible factor 1 (HIF-1, controlling angiogenic and metastatic pathways. Methods We investigated the effect of CA-4-P on factors of the upstream and downstream signalling pathway of HIF-1 in vitro. Results CA-4-P treatment under hypoxia tended to reduce HIF-1 accumulation in a concentration-dependent manner, an effect which was more prominent in endothelial cells than in cancer cell lines. Conversely, CA-4-P increased HIF-1 accumulation under aerobic conditions in vitro. At these concentrations of CA-4-P under aerobic conditions, nuclear factor κB was activated via the small GTPase RhoA, and expression of the HIF-1 downstream angiogenic effector gene, vascular endothelial growth factor (VEGF-A, was increased. Conclusion Our findings advance the understanding of signal transduction pathways involved in the actions of the anti-vascular agent CA-4-P.

  5. Diabetes and Retinal Vascular Dysfunction

    Directory of Open Access Journals (Sweden)

    Eui Seok Shin

    2014-01-01

    Full Text Available Diabetes predominantly affects the microvascular circulation of the retina resulting in a range of structural changes unique to this tissue. These changes ultimately lead to altered permeability, hyperproliferation of endothelial cells and edema, and abnormal vascularization of the retina with resulting loss of vision. Enhanced production of inflammatory mediators and oxidative stress are primary insults with significant contribution to the pathogenesis of diabetic retinopathy (DR. We have determined the identity of the retinal vascular cells affected by hyperglycemia, and have delineated the cell autonomous impact of high glucose on function of these cells. We discuss some of the high glucose specific changes in retinal vascular cells and their contribution to retinal vascular dysfunction. This knowledge provides novel insight into the molecular and cellular defects contributing to the development and progression of diabetic retinopathy, and will aid in the development of innovative, as well as target specific therapeutic approaches for prevention and treatment of DR.

  6. Cigarette smoke regulates VEGFR2-mediated survival signaling in rat lungs

    Directory of Open Access Journals (Sweden)

    Stevenson Christopher S

    2010-02-01

    Full Text Available Abstract Background Vascular endothelial growth factor (VEGF and VEGF receptor 2 (VEGFR2-mediated survival signaling is critical to endothelial cell survival, maintenance of the vasculature and alveolar structure and regeneration of lung tissue. Reduced VEGF and VEGFR2 expression in emphysematous lungs has been linked to increased endothelial cell death and vascular regression. Previously, we have shown that CS down-regulated the VEGFR2 and its downstream signaling in mouse lungs. However, the VEGFR2-mediated survival signaling in response to oxidants/cigarette smoke (CS is not known. We hypothesized that CS exposure leads to disruption of VEGFR2-mediated endothelial survival signaling in rat lungs. Methods Adult male Sprague-Dawley rats were exposed CS for 3 days, 8 weeks and 6 months to investigate the effect of CS on VEGFR2-mediated survival signaling by measuring the Akt/PI3-kinase/eNOS downstream signaling in rat lungs. Results and Discussion We show that CS disrupts VEGFR2/PI3-kinase association leading to decreased Akt and eNOS phosphorylation. This may further alter the phosphorylation of the pro-apoptotic protein Bad and increase the Bad/Bcl-xl association. However, this was not associated with a significant lung cell death as evidenced by active caspase-3 levels. These data suggest that although CS altered the VEGFR2-mediated survival signaling in the rat lungs, but it was not sufficient to cause lung cell death. Conclusion The rat lungs exposed to CS in acute, sub-chronic and chronic levels may be representative of smokers where survival signaling is altered but was not associated with lung cell death whereas emphysema is known to be associated with lung cell apoptosis.

  7. Coupling Planar Cell Polarity Signaling to Morphogenesis

    Directory of Open Access Journals (Sweden)

    Jeffrey D. Axelrod

    2002-01-01

    Full Text Available Epithelial cells and other groups of cells acquire a polarity orthogonal to their apical–basal axes, referred to as Planar Cell Polarity (PCP. The process by which these cells become polarized requires a signaling pathway using Frizzled as a receptor. Responding cells sense cues from their environment that provide directional information, and they translate this information into cellular asymmetry. Most of what is known about PCP derives from studies in the fruit fly, Drosophila. We review what is known about how cells translate an unknown signal into asymmetric cytoskeletal reorganization. We then discuss how the vertebrate processes of convergent extension and cochlear hair-cell development may relate to Drosophila PCP signaling.

  8. Emerging Role of Angiotensin Type 2 Receptor (AT2R)/Akt/NO Pathway in Vascular Smooth Muscle Cell in the Hyperthyroidism

    Science.gov (United States)

    Carrillo-Sepúlveda, Maria Alícia; Ceravolo, Graziela S.; Furstenau, Cristina R.; Monteiro, Priscilla de Souza; Bruno-Fortes, Zuleica; Carvalho, Maria Helena; Laurindo, Francisco R.; Tostes, Rita C.; Webb, R. Clinton; Barreto-Chaves, Maria Luiza M.

    2013-01-01

    Hyperthyroidism is characterized by increased vascular relaxation and decreased vascular contraction and is associated with augmented levels of triiodothyronine (T3) that contribute to the diminished systemic vascular resistance found in this condition. T3 leads to augmented NO production via PI3K/Akt signaling pathway, which in turn causes vascular smooth muscle cell (VSMC) relaxation; however, the underlying mechanisms involved remain largely unknown. Evidence from human and animal studies demonstrates that the renin-angiotensin system (RAS) plays a crucial role in vascular function and also mediates some of cardiovascular effects found during hyperthyroidism. Thus, in this study, we hypothesized that type 2 angiotensin II receptor (AT2R), a key component of RAS vasodilatory actions, mediates T3 induced-decreased vascular contraction. Marked induction of AT2R expression was observed in aortas from T3-induced hyperthyroid rats (Hyper). These vessels showed decreased protein levels of the contractile apparatus: α-actin, calponin and phosphorylated myosin light chain (p-MLC). Vascular reactivity studies showed that denuded aortic rings from Hyper rats exhibited decreased maximal contractile response to angiotensin II (AngII), which was attenuated in aortic rings pre-incubated with an AT2R blocker. Further study showed that cultured VSMC stimulated with T3 (0.1 µmol/L) for 24 hours had increased AT2R gene and protein expression. Augmented NO levels and decreased p-MLC levels were found in VSMC stimulated with T3, both of which were reversed by a PI3K/Akt inhibitor and AT2R blocker. These findings indicate for the first time that the AT2R/Akt/NO pathway contributes to decreased contractile responses in rat aorta, promoted by T3, and this mechanism is independent from the endothelium. PMID:23637941

  9. Emerging role of angiotensin type 2 receptor (AT2R/Akt/NO pathway in vascular smooth muscle cell in the hyperthyroidism.

    Directory of Open Access Journals (Sweden)

    Maria Alícia Carrillo-Sepúlveda

    Full Text Available Hyperthyroidism is characterized by increased vascular relaxation and decreased vascular contraction and is associated with augmented levels of triiodothyronine (T3 that contribute to the diminished systemic vascular resistance found in this condition. T3 leads to augmented NO production via PI3K/Akt signaling pathway, which in turn causes vascular smooth muscle cell (VSMC relaxation; however, the underlying mechanisms involved remain largely unknown. Evidence from human and animal studies demonstrates that the renin-angiotensin system (RAS plays a crucial role in vascular function and also mediates some of cardiovascular effects found during hyperthyroidism. Thus, in this study, we hypothesized that type 2 angiotensin II receptor (AT2R, a key component of RAS vasodilatory actions, mediates T3 induced-decreased vascular contraction. Marked induction of AT2R expression was observed in aortas from T3-induced hyperthyroid rats (Hyper. These vessels showed decreased protein levels of the contractile apparatus: α-actin, calponin and phosphorylated myosin light chain (p-MLC. Vascular reactivity studies showed that denuded aortic rings from Hyper rats exhibited decreased maximal contractile response to angiotensin II (AngII, which was attenuated in aortic rings pre-incubated with an AT2R blocker. Further study showed that cultured VSMC stimulated with T3 (0.1 µmol/L for 24 hours had increased AT2R gene and protein expression. Augmented NO levels and decreased p-MLC levels were found in VSMC stimulated with T3, both of which were reversed by a PI3K/Akt inhibitor and AT2R blocker. These findings indicate for the first time that the AT2R/Akt/NO pathway contributes to decreased contractile responses in rat aorta, promoted by T3, and this mechanism is independent from the endothelium.

  10. Vascular development in the vertebrate pancreas

    Science.gov (United States)

    Azizoglu, D. Berfin; Chong, Diana C.; Villasenor, Alethia; Magenheim, Judith; Barry, David M.; Lee, Simon; Marty-Santos, Leilani; Fu, Stephen; Dor, Yuval; Cleaver, Ondine

    2016-01-01

    The vertebrate pancreas is comprised of a highly branched tubular epithelium, which is intimately associated with an extensive and specialized vasculature. While we know a great deal about basic vascular anatomy of the adult pancreas, as well as islet capillaries, surprisingly little is known about the ontogeny of its blood vessels. Here, we analyze development of the pancreatic vasculature in the mouse embryo. We show that pancreatic epithelial branches intercalate with the fine capillary plexus of the surrounding pancreatic mesenchyme. Endothelial cells (ECs) within this mesenchyme are heterogeneous from the onset of organogenesis. Pancreatic arteries take shape before veins, in a manner analogous to early embryonic vessels. The main central artery forms during mid-gestation, as a result of vessel coalescence and remodeling of a vascular plexus. In addition, we show that vessels in the forming pancreas display a predictable architecture that is dependent on VEGF signaling. Over-expression of VEGF disrupts vascular patterning and arteriovenous differentiation within the developing pancreas. This study constitutes a first-time cellular and molecular characterization of pancreatic blood vessels, as they coordinately grow along with the pancreatic epithelium. PMID:27789228

  11. Vascular development in the vertebrate pancreas.

    Science.gov (United States)

    Azizoglu, D Berfin; Chong, Diana C; Villasenor, Alethia; Magenheim, Judith; Barry, David M; Lee, Simon; Marty-Santos, Leilani; Fu, Stephen; Dor, Yuval; Cleaver, Ondine

    2016-12-01

    The vertebrate pancreas is comprised of a highly branched tubular epithelium, which is intimately associated with an extensive and specialized vasculature. While we know a great deal about basic vascular anatomy of the adult pancreas, as well as islet capillaries, surprisingly little is known about the ontogeny of its blood vessels. Here, we analyze development of the pancreatic vasculature in the mouse embryo. We show that pancreatic epithelial branches intercalate with the fine capillary plexus of the surrounding pancreatic mesenchyme. Endothelial cells (ECs) within this mesenchyme are heterogeneous from the onset of organogenesis. Pancreatic arteries take shape before veins, in a manner analogous to early embryonic vessels. The main central artery forms during mid-gestation, as a result of vessel coalescence and remodeling of a vascular plexus. In addition, we show that vessels in the forming pancreas display a predictable architecture that is dependent on VEGF signaling. Over-expression of VEGF disrupts vascular patterning and arteriovenous differentiation within the developing pancreas. This study constitutes a first-time in-depth cellular and molecular characterization of pancreatic blood vessels, as they coordinately grow along with the pancreatic epithelium. Copyright © 2016 Elsevier Inc. All rights reserved.

  12. Ubiquitination of basal VEGFR2 regulates signal transduction and endothelial function.

    Science.gov (United States)

    Smith, Gina A; Fearnley, Gareth W; Abdul-Zani, Izma; Wheatcroft, Stephen B; Tomlinson, Darren C; Harrison, Michael A; Ponnambalam, Sreenivasan

    2017-10-15

    Cell surface receptors can undergo recycling or proteolysis but the cellular decision-making events that sort between these pathways remain poorly defined. Vascular endothelial growth factor A (VEGF-A) and vascular endothelial growth factor receptor 2 (VEGFR2) regulate signal transduction and angiogenesis, but how signaling and proteolysis is regulated is not well understood. Here, we provide evidence that a pathway requiring the E1 ubiquitin-activating enzyme UBA1 controls basal VEGFR2 levels, hence metering plasma membrane receptor availability for the VEGF-A-regulated endothelial cell response. VEGFR2 undergoes VEGF-A-independent constitutive degradation via a UBA1-dependent ubiquitin-linked pathway. Depletion of UBA1 increased VEGFR2 recycling from endosome-to-plasma membrane and decreased proteolysis. Increased membrane receptor availability after UBA1 depletion elevated VEGF-A-stimulated activation of key signaling enzymes such as PLCγ1 and ERK1/2. Although UBA1 depletion caused an overall decrease in endothelial cell proliferation, surviving cells showed greater VEGF-A-stimulated responses such as cell migration and tubulogenesis. Our study now suggests that a ubiquitin-linked pathway regulates the balance between receptor recycling and degradation which in turn impacts on the intensity and duration of VEGF-A-stimulated signal transduction and the endothelial response. © 2017. Published by The Company of Biologists Ltd.

  13. Regulation of plant vascular stem cells by endodermis-derived EPFL-family peptide hormones and phloem-expressed ERECTA-family receptor kinases.

    Science.gov (United States)

    Uchida, Naoyuki; Tasaka, Masao

    2013-12-01

    Plant vasculatures are complex tissues consisting of (pro)cambium, phloem, and xylem. The (pro)cambium serves as vascular stem cells that produce all vascular cells. The Arabidopsis ERECTA (ER) receptor kinase is known to regulate the architecture of inflorescence stems. It was recently reported that the er mutation enhances a vascular phenotype induced by a mutation of TDR/PXY, which plays a significant role in procambial proliferation, suggesting that ER participates in vascular development. However, detailed molecular mechanisms of the ER-dependent vascular regulation are largely unknown. Here, this work found that ER and its paralogue, ER-LIKE1, were redundantly involved in procambial development of inflorescence stems. Interestingly, their activity in the phloem was sufficient for vascular regulation. Furthermore, two endodermis-derived peptide hormones, EPFL4 and EPFL6, were redundantly involved in such regulation. It has been previously reported that EPFL4 and EPFL6 act as ligands of phloem-expressed ER for stem elongation. Therefore, these findings indicate that cell-cell communication between the endodermis and the phloem plays an important role in procambial development as well as stem elongation. Interestingly, similar EPFL-ER modules control two distinct developmental events by slightly changing their components: the EPFL4/6-ER module for stem elongation and the EPFL4/6-ER/ERL1 module for vascular development.

  14. Decoding Signal Processing at the Single-Cell Level

    Energy Technology Data Exchange (ETDEWEB)

    Wiley, H. Steven

    2017-12-01

    The ability of cells to detect and decode information about their extracellular environment is critical to generating an appropriate response. In multicellular organisms, cells must decode dozens of signals from their neighbors and extracellular matrix to maintain tissue homeostasis while still responding to environmental stressors. How cells detect and process information from their surroundings through a surprisingly limited number of signal transduction pathways is one of the most important question in biology. Despite many decades of research, many of the fundamental principles that underlie cell signal processing remain obscure. However, in this issue of Cell Systems, Gillies et al present compelling evidence that the early response gene circuit can act as a linear signal integrator, thus providing significant insight into how cells handle fluctuating signals and noise in their environment.

  15. Engineered, axially-vascularized osteogenic grafts from human adipose-derived cells to treat avascular necrosis of bone in a rat model.

    Science.gov (United States)

    Ismail, Tarek; Osinga, Rik; Todorov, Atanas; Haumer, Alexander; Tchang, Laurent A; Epple, Christian; Allafi, Nima; Menzi, Nadia; Largo, René D; Kaempfen, Alexandre; Martin, Ivan; Schaefer, Dirk J; Scherberich, Arnaud

    2017-11-01

    Avascular necrosis of bone (AVN) leads to sclerosis and collapse of bone and joints. The standard of care, vascularized bone grafts, is limited by donor site morbidity and restricted availability. The aim of this study was to generate and test engineered, axially vascularized SVF cells-based bone substitutes in a rat model of AVN. SVF cells were isolated from lipoaspirates and cultured onto porous hydroxyapatite scaffolds within a perfusion-based bioreactor system for 5days. The resulting constructs were inserted into devitalized bone cylinders mimicking AVN-affected bone. A ligated vascular bundle was inserted upon subcutaneous implantation of constructs in nude rats. After 1 and 8weeks in vivo, bone formation and vascularization were analyzed. Newly-formed bone was found in 80% of SVF-seeded scaffolds after 8weeks but not in unseeded controls. Human ALU+cells in the bone structures evidenced a direct contribution of SVF cells to bone formation. A higher density of regenerative, M2 macrophages was observed in SVF-seeded constructs. In both experimental groups, devitalized bone was revitalized by vascularized tissue after 8 weeks. SVF cells-based osteogenic constructs revitalized fully necrotic bone in a challenging AVN rat model of clinically-relevant size. SVF cells contributed to accelerated initial vascularization, to bone formation and to recruitment of pro-regenerative endogenous cells. Avascular necrosis (AVN) of bone often requires surgical treatment with autologous bone grafts, which is surgically demanding and restricted by significant donor site morbidity and limited availability. This paper describes a de novo engineered axially-vascularized bone graft substitute and tests the potential to revitalize dead bone and provide efficient new bone formation in a rat model. The engineering of an osteogenic/vasculogenic construct of clinically-relevant size with stromal vascular fraction of human adipose, combined to an arteriovenous bundle is described. This

  16. Effect of essential fatty acids on glucose-induced cytotoxicity to retinal vascular endothelial cells

    Directory of Open Access Journals (Sweden)

    Shen Junhui

    2012-07-01

    Full Text Available Abstract Background Diabetic retinopathy is a major complication of dysregulated hyperglycemia. Retinal vascular endothelial cell dysfunction is an early event in the pathogenesis of diabetic retinopathy. Studies showed that hyperglycemia-induced excess proliferation of retinal vascular endothelial cells can be abrogated by docosahexaenoic acid (DHA, 22:6 ω-3 and eicosapentaenoic acid (EPA, 20:5 ω-3. The influence of dietary omega-3 PUFA on brain zinc metabolism has been previously implied. Zn2+ is essential for the activity of Δ6 desaturase as a co-factor that, in turn, converts essential fatty acids to their respective long chain metabolites. Whether essential fatty acids (EFAs α-linolenic acid and linoleic acid have similar beneficial effect remains poorly understood. Methods RF/6A cells were treated with different concentrations of high glucose, α-linolenic acid and linoleic acid and Zn2+. The alterations in mitochondrial succinate dehydrogenase enzyme activity, cell membrane fluidity, reactive oxygen species generation, SOD enzyme and vascular endothelial growth factor (VEGF secretion were evaluated. Results Studies showed that hyperglycemia-induced excess proliferation of retinal vascular endothelial cells can be abrogated by both linoleic acid (LA and α-linolenic acid (ALA, while the saturated fatty acid, palmitic acid was ineffective. A dose–response study with ALA showed that the activity of the mitochondrial succinate dehydrogenase enzyme was suppressed at all concentrations of glucose tested to a significant degree. High glucose enhanced fluorescence polarization and microviscocity reverted to normal by treatment with Zn2+ and ALA. ALA was more potent that Zn2+. Increased level of high glucose caused slightly increased ROS generation that correlated with corresponding decrease in SOD activity. ALA suppressed ROS generation to a significant degree in a dose dependent fashion and raised SOD activity significantly. ALA suppressed

  17. Treating fat grafts with human endothelial progenitor cells promotes their vascularization and improves their survival in diabetes mellitus.

    Science.gov (United States)

    Hamed, Saher; Ben-Nun, Ohad; Egozi, Dana; Keren, Aviad; Malyarova, Nastya; Kruchevsky, Danny; Gilhar, Amos; Ullmann, Yehuda

    2012-10-01

    Bone marrow-derived endothelial progenitor cells are required for vascularization of a fat graft to form a functional microvasculature within the graft and to facilitate its integration into the surrounding tissues. Organ transplantation carries a high risk of graft loss and rejection in patients with diabetes mellitus because endothelial progenitor cell function is impaired. The authors investigated the influence of endothelial progenitor cell treatment on the phenotype and survival of human fat grafts in immunocompromised mice with experimentally induced diabetes mellitus. The authors injected 1 ml of human fat tissue into the scalps of 14 nondiabetic and 28 diabetic immunocompromised mice, and then treated some of the grafts with endothelial progenitor cells that was isolated from the blood of a human donor. The phenotype of the endothelial progenitor cell-treated fat grafts from the 14 diabetic mice was compared with that of the untreated fat grafts from 14 nondiabetic and 14 diabetic mice, 18 days and 15 weeks after fat transplantation. Determination of graft phenotype included measurements of weight and volume, vascular endothelial growth factor levels, vascular endothelial growth factor receptor-2, endothelial nitric oxide synthase, and caspase 3 expression levels, and histologic analysis of the extent of vascularization. The untreated grafts from the diabetic mice were fully resorbed 15 weeks after fat transplantation. The phenotype of endothelial progenitor cell-treated fat grafts from the diabetic mice was similar to that of the untreated fat grafts from the nondiabetic mice. Endothelial progenitor cell treatment of transplanted fat can increase the survival of a fat graft by inducing its vascularization and decreasing the extent of apoptosis.

  18. Endothelial Estrogen Receptor-α Does Not Protect Against Vascular Stiffness Induced by Western Diet in Female Mice.

    Science.gov (United States)

    Manrique, Camila; Lastra, Guido; Ramirez-Perez, Francisco I; Haertling, Dominic; DeMarco, Vincent G; Aroor, Annayya R; Jia, Guanghong; Chen, Dongqing; Barron, Brady J; Garro, Mona; Padilla, Jaume; Martinez-Lemus, Luis A; Sowers, James R

    2016-04-01

    Consumption of a diet high in fat and refined carbohydrates (Western diet [WD]) is associated with obesity and insulin resistance, both major risk factors for cardiovascular disease (CVD). In women, obesity and insulin resistance abrogate the protection against CVD likely afforded by estrogen signaling through estrogen receptor (ER)α. Indeed, WD in females results in increased vascular stiffness, which is independently associated with CVD. We tested the hypothesis that loss of ERα signaling in the endothelium exacerbates WD-induced vascular stiffening in female mice. We used a novel model of endothelial cell (EC)-specific ERα knockout (EC-ERαKO), obtained after sequential crossing of the ERα double floxed mice and VE-Cadherin Cre-recombinase mice. Ten-week-old females, EC-ERαKO and aged-matched genopairs were fed either a regular chow diet (control diet) or WD for 8 weeks. Vascular stiffness was measured in vivo by pulse wave velocity and ex vivo in aortic explants by atomic force microscopy. In addition, vascular reactivity was assessed in isolated aortic rings. Initial characterization of the model fed a control diet did not reveal changes in whole-body insulin sensitivity, aortic vasoreactivity, or vascular stiffness in the EC-ERαKO mice. Interestingly, ablation of ERα in ECs reduced WD-induced vascular stiffness and improved endothelial-dependent dilation. In the setting of a WD, endothelial ERα signaling contributes to vascular stiffening in females. The precise mechanisms underlying the detrimental effects of endothelial ERα in the setting of a WD remain to be elucidated.

  19. Restoration of autophagy in endothelial cells from patients with diabetes mellitus improves nitric oxide signaling.

    Science.gov (United States)

    Fetterman, Jessica L; Holbrook, Monica; Flint, Nir; Feng, Bihua; Bretón-Romero, Rosa; Linder, Erika A; Berk, Brittany D; Duess, Mai-Ann; Farb, Melissa G; Gokce, Noyan; Shirihai, Orian S; Hamburg, Naomi M; Vita, Joseph A

    2016-04-01

    Endothelial dysfunction contributes to cardiovascular disease in diabetes mellitus. Autophagy is a multistep mechanism for the removal of damaged proteins and organelles from the cell. Under diabetic conditions, inadequate autophagy promotes cellular dysfunction and insulin resistance in non-vascular tissue. We hypothesized that impaired autophagy contributes to endothelial dysfunction in diabetes mellitus. We measured autophagy markers and endothelial nitric oxide synthase (eNOS) activation in freshly isolated endothelial cells from diabetic subjects (n = 45) and non-diabetic controls (n = 41). p62 levels were higher in cells from diabetics (34.2 ± 3.6 vs. 20.0 ± 1.6, P = 0.001), indicating reduced autophagic flux. Bafilomycin inhibited insulin-induced activation of eNOS (64.7 ± 22% to -47.8 ± 8%, P = 0.04) in cells from controls, confirming that intact autophagy is necessary for eNOS signaling. In endothelial cells from diabetics, activation of autophagy with spermidine restored eNOS activation, suggesting that impaired autophagy contributes to endothelial dysfunction (P = 0.01). Indicators of autophagy initiation including the number of LC3-bound puncta and beclin 1 expression were similar in diabetics and controls, whereas an autophagy terminal phase indicator, the lysosomal protein Lamp2a, was higher in diabetics. In endothelial cells under diabetic conditions, the beneficial effect of spermidine on eNOS activation was blocked by autophagy inhibitors bafilomycin or 3-methyladenine. Blocking the terminal stage of autophagy with bafilomycin increased p62 (P = 0.01) in cells from diabetics to a lesser extent than in cells from controls (P = 0.04), suggesting ongoing, but inadequate autophagic clearance. Inadequate autophagy contributes to endothelial dysfunction in patients with diabetes and may be a target for therapy of diabetic vascular disease. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  20. Vascular Endothelial Growth Factor Receptor 1 Contributes to Escherichia coli K1 Invasion of Human Brain Microvascular Endothelial Cells through the Phosphatidylinositol 3-Kinase/Akt Signaling Pathway▿ †

    OpenAIRE

    Zhao, Wei-Dong; Liu, Wei; Fang, Wen-Gang; Kim, Kwang Sik; Chen, Yu-Hua

    2010-01-01

    Escherichia coli is the most common Gram-negative organism causing neonatal meningitis. Previous studies demonstrated that E. coli K1 invasion of brain microvascular endothelial cells (BMEC) is required for penetration into the central nervous system, but the microbe-host interactions that are involved in this process remain incompletely understood. Here we report the involvement of vascular endothelial growth factor receptor 1 (VEGFR1) expressed on human brain microvascular endothelial cells...

  1. Nonimmune cells equipped with T-cell-receptor-like signaling for cancer cell ablation.

    Science.gov (United States)

    Kojima, Ryosuke; Scheller, Leo; Fussenegger, Martin

    2018-01-01

    The ability to engineer custom cell-contact-sensing output devices into human nonimmune cells would be useful for extending the applicability of cell-based cancer therapies and for avoiding risks associated with engineered immune cells. Here we have developed a new class of synthetic T-cell receptor-like signal-transduction device that functions efficiently in human nonimmune cells and triggers release of output molecules specifically upon sensing contact with a target cell. This device employs an interleukin signaling cascade, whose OFF/ON switching is controlled by biophysical segregation of a transmembrane signal-inhibitory protein from the sensor cell-target cell interface. We further show that designer nonimmune cells equipped with this device driving expression of a membrane-penetrator/prodrug-activating enzyme construct could specifically kill target cells in the presence of the prodrug, indicating its potential usefulness for target-cell-specific, cell-based enzyme-prodrug cancer therapy. Our study also contributes to the advancement of synthetic biology by extending available design principles to transmit extracellular information to cells.

  2. Progranulin protects vascular endothelium against atherosclerotic inflammatory reaction via Akt/eNOS and nuclear factor-κB pathways.

    Science.gov (United States)

    Hwang, Hwan-Jin; Jung, Tae Woo; Hong, Ho Cheol; Choi, Hae Yoon; Seo, Ji-A; Kim, Sin Gon; Kim, Nan Hee; Choi, Kyung Mook; Choi, Dong Seop; Baik, Sei Hyun; Yoo, Hye Jin

    2013-01-01

    Atherosclerosis is considered a chronic inflammatory disease, initiated by activation and dysfunction of the endothelium. Recently, progranulin has been regarded as an important modulator of inflammatory processes; however, the role for prgranulin in regulating inflammation in vascular endothelial cells has not been described. Signaling pathways mediated by progranulin were analyzed in human umbilical vein endothelial cells (HUVECs) treated with progranulin. Progranulin significantly induced Akt and endothelial nitric oxide synthase (eNOS) phosphorylation in HUVECs, an effect that was blocked with Akt inhibitor. Furthermore, nitric oxide (NO) level, the end product of Akt/eNOS pathway, was significantly upregulated after progranulin treatment. Next, we showed that progranulin efficiently inhibited lipopolysaccharide (LPS)-mediated pro-inflammatory signaling. LPS-induced phosphorylation of IκB and nuclear factor-κB (NF-κB) levels decreased after progranulin treatment. Also, progranulin blocked translocation of NF-κB from the cytosol to the nucleus. In addition, progranulin significantly reduced the expression of vascular cell adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1 (ICAM-1) by inhibiting binding of NF- κB to their promoter regions and blocked attachment of monocytes to HUVECs. Progranulin also significantly reduced the expression of tumor necrosis factor receptor-α (TNF-α) and monocyte chemo-attractant protein-1 (MCP-1), the crucial inflammatory molecules known to aggravate atherosclerosis. Progranulin efficiently inhibited LPS-mediated pro-inflammatory signaling in endothelial cells through activation of the Akt/eNOS pathway and attenuation of the NF-κB pathway, suggesting its protective roles in vascular endothelium against inflammatory reaction underlying atherosclerosis.

  3. The Haematopoietic Stem Cell Niche: New Insights into the Mechanisms Regulating Haematopoietic Stem Cell Behaviour

    Directory of Open Access Journals (Sweden)

    Andrew J. Lilly

    2011-01-01

    Full Text Available The concept of the haematopoietic stem cell (HSC niche was formulated by Schofield in the 1970s, as a region within the bone marrow containing functional cell types that can maintain HSC potency throughout life. Since then, ongoing research has identified numerous cell types and a plethora of signals that not only maintain HSCs, but also dictate their behaviour with respect to homeostatic requirements and exogenous stresses. It has been proposed that there are endosteal and vascular niches within the bone marrow, which are thought to regulate different HSC populations. However, recent data depicts a more complicated picture, with functional crosstalk between cells in these two regions. In this review, recent research into the endosteal/vascular cell types and signals regulating HSC behaviour are considered, together with the possibility of a single subcompartmentalised niche.

  4. Illegitimate WNT signaling promotes proliferation of multiple myeloma cells

    Science.gov (United States)

    Derksen, Patrick W. B.; Tjin, Esther; Meijer, Helen P.; Klok, Melanie D.; Mac Gillavry, Harold D.; van Oers, Marinus H. J.; Lokhorst, Henk M.; Bloem, Andries C.; Clevers, Hans; Nusse, Roel; van der Neut, Ronald; Spaargaren, Marcel; Pals, Steven T.

    2004-01-01

    The unrestrained growth of tumor cells is generally attributed to mutations in essential growth control genes, but tumor cells are also influenced by signals from the environment. In multiple myeloma (MM), the factors and signals coming from the bone marrow microenvironment are possibly even essential for the growth of the tumor cells. As targets for intervention, these signals may be equally important as mutated oncogenes. Given their oncogenic potential, WNT signals form a class of paracrine growth factors that could act to influence MM cell growth. In this paper, we report that MM cells have hallmarks of active WNT signaling, whereas the cells have not undergone detectable mutations in WNT signaling genes such as adenomatous polyposis coli and β-catenin (CTNNB1). We show that the malignant MM plasma cells overexpress β-catenin, including its N-terminally unphosphorylated form, suggesting active β-catenin/T cell factor-mediated transcription. Further accumulation and nuclear localization of β-catenin, and/or increased cell proliferation, was achieved by stimulation of WNT signaling with either Wnt3a, LiCl, or the constitutively active S33Y mutant of β-catenin. In contrast, by blocking WNT signaling by dominant-negative T cell factor, we can interfere with the growth of MM cells. We therefore suggest that MM cells are dependent on an active WNT signal, which may have important implications for the management of this incurable form of cancer. PMID:15067127

  5. Double-filter identification of vascular-expressed genes using Arabidopsis plants with vascular hypertrophy and hypotrophy.

    Science.gov (United States)

    Ckurshumova, Wenzislava; Scarpella, Enrico; Goldstein, Rochelle S; Berleth, Thomas

    2011-08-01

    Genes expressed in vascular tissues have been identified by several strategies, usually with a focus on mature vascular cells. In this study, we explored the possibility of using two opposite types of altered tissue compositions in combination with a double-filter selection to identify genes with a high probability of vascular expression in early organ primordia. Specifically, we generated full-transcriptome microarray profiles of plants with (a) genetically strongly reduced and (b) pharmacologically vastly increased vascular tissues and identified a reproducible cohort of 158 transcripts that fulfilled the dual requirement of being underrepresented in (a) and overrepresented in (b). In order to assess the predictive value of our identification scheme for vascular gene expression, we determined the expression patterns of genes in two unbiased subsamples. First, we assessed the expression patterns of all twenty annotated transcription factor genes from the cohort of 158 genes and found that seventeen of the twenty genes were preferentially expressed in leaf vascular cells. Remarkably, fifteen of these seventeen vascular genes were clearly expressed already very early in leaf vein development. Twelve genes with published leaf expression patterns served as a second subsample to monitor the representation of vascular genes in our cohort. Of those twelve genes, eleven were preferentially expressed in leaf vascular tissues. Based on these results we propose that our compendium of 158 genes represents a sample that is highly enriched for genes expressed in vascular tissues and that our approach is particularly suited to detect genes expressed in vascular cell lineages at early stages of their inception. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  6. Spironolactone treatment attenuates vascular dysfunction in type 2 diabetic mice by decreasing oxidative stress and restoring NO/GC signaling

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    Marcondes Alves Barbosa Da Silva

    2015-10-01

    Full Text Available Type 2 diabetes (DM2 increases the risk of cardiovascular disease. Aldosterone, which has pro-oxidative and pro-inflammatory effects in the cardiovascular system, is positively regulated in DM2. We assessed whether blockade of mineralocorticoid receptors (MR with spironolactone decreases ROS-associated vascular dysfunction and improves vascular NO signaling in diabetes. Leptin receptor knockout [LepRdb/LepRdb (db/db] mice, a model of DM2, and their counterpart controls [LepRdb/LepR+, (db/+ mice] received spironolactone (50 mg/kg body weight/day or vehicle (ethanol 1% via oral per gavage for 6 weeks. Spironolactone treatment abolished the endothelial dysfunction and increased endothelial nitric oxide synthase (eNOS phosphorylation (Ser1177, determined by acetylcholine-induced relaxation and Western Blot analysis, respectively. MR antagonist therapy also abrogated augmented ROS-generation in aorta from diabetic mice, determined by lucigenin luminescence assay. Spironolactone treatment increased superoxide dismutase-1 (SOD1 and catalase expression, improved sodium nitroprusside (SNP and BAY 41-2272-induced relaxation, as well as increased soluble guanylyl cyclase (sGC subunit β protein expression in arteries from db/db mice. Our results demonstrate that spironolactone decreases diabetes-associated vascular oxidative stress and prevents vascular dysfunction through processes involving increased expression of antioxidant enzymes and sGC. These findings further elucidate redox-sensitive mechanisms whereby spironolactone protects against vascular injury in diabetes.

  7. Excitation-contraction coupling and excitation-transcription coupling in blood vessels: their possible interactions in hypertensive vascular remodeling

    Czech Academy of Sciences Publication Activity Database

    Misárková, Eliška; Behuliak, Michal; Bencze, Michal; Zicha, Josef

    2016-01-01

    Roč. 65, č. 2 (2016), s. 173-191 ISSN 0862-8408 R&D Projects: GA MZd(CZ) NV15-25396A Institutional support: RVO:67985823 Keywords : vascular smooth muscle cells * contractile VSMC phenotype * proliferative VSMC phenotype * cell Ca2+ handling * intracellular signaling pathways Subject RIV: FA - Cardiovascular Diseases incl. Cardiotharic Surgery Impact factor: 1.461, year: 2016

  8. 1-o-acetylbritannilactone (ABL) inhibits angiogenesis and lung cancer cell growth through regulating VEGF-Src-FAK signaling

    Energy Technology Data Exchange (ETDEWEB)

    Zhengfu, He; Hu, Zhang; Huiwen, Miao; Zhijun, Li [Department of Thoracic Surgery, Sir Run Run Shaw Hospital of Zhejiang University School of Medicine, Hangzhou (China); Jiaojie, Zhou [Zhejiang University School of Medicine, Hangzhou (China); Xiaoyi, Yan, E-mail: xiaoyiyan163@163.com [Zhejiang University School of Medicine, Hangzhou (China); Xiujun, Cai, E-mail: xiujuncaomaj@163.com [Sir Run Run Shaw Hospital of Zhejiang University School of Medicine, Hangzhou (China)

    2015-08-21

    The search for safe, effective and affordable therapeutics against non-small cell lung cancer (NSCLC) and other lung cancers is important. Here we explored the potential effect of 1-o-acetylbritannilactone (ABL), a novel extract from Inula britannica-F, on angiogenesis and lung cancer cell growth. We demonstrated that ABL dose-dependently inhibited vascular endothelial growth factor (VEGF)-induced proliferation, migration, and capillary structure formation of cultured human umbilical vascular endothelial cells (HUVECs). In vivo, ABL administration suppressed VEGF-induced new vasculature formation in Matrigel plugs. For the mechanism investigations, we found that ABL largely inhibited VEGF-mediated activation of Src kinase and focal adhesion kinase (FAK) in HUVECs. Furthermore, treatment of A549 NSCLC cells with ABL resulted in cell growth inhibition and Src-FAK in-activation. Significantly, administration of a single dose of ABL (12 mg/kg/day) remarkably suppressed growth of A549 xenografts in nude mice. In vivo microvessels formation and Src activation were also significantly inhibited in ABL-treated xenograft tumors. Taken together, our findings suggest that ABL suppresses angiogenesis and lung cancer cell growth possibly via regulating the VEGFR-Src-FAK signaling. - Highlights: • 1-o-acetylbritannilactone (ABL) inhibits VEGF-induced angiogenesis in vivo. • ABL inhibits VEGF-induced HUVEC migration, proliferation, capillary tube formation. • ABL inhibits VEGF-mediated activation of Src and FAK in HUVECs. • ABL inhibits growth and Src-FAK activation in A549 cells. • ABL administration inhibits A549 tumor angiogenesis and growth in nude mice.

  9. Intermittent injections of osteocalcin reverse autophagic dysfunction and endoplasmic reticulum stress resulting from diet-induced obesity in the vascular tissue via the NFκB-p65-dependent mechanism.

    Science.gov (United States)

    Zhou, Bo; Li, Huixia; Liu, Jiali; Xu, Lin; Zang, Weijin; Wu, Shufang; Sun, Hongzhi

    2013-06-15

    The osteoblast-specific secreted molecule osteocalcin behaves as a hormone-regulating glucose and lipid metabolism, but the role of osteocalcin in cardiovascular disease (CVD) is not fully understood. In the present study, we investigated the effect of osteocalcin on autophagy and endoplasmic reticulum (ER) stress secondary to diet-induced obesity in the vascular tissue of mice and in vascular cell models and clarified the intracellular events responsible for osteocalcin-mediated effects. The evidences showed that intermittent injections of osteocalcin in mice fed the high-fat diet were associated with a reduced body weight gain, decreased blood glucose and improved insulin sensitivity compared with mice fed the high-fat diet receiving vehicle. Simultaneously, the administration of osteocalcin not only attenuated autophagy and ER stress but also rescued impaired insulin signaling in vascular tissues of mice fed a high-fat diet. Consistent with these results in vivo, the addition of osteocalcin reversed autophagy and ER stress and restored defective insulin sensitivity in vascular endothelial cells (VECs) and vascular smooth muscle cells (VSMCs) in the presence of tunicamycin or in knockout XBP-1 (a transcription factor which mediates ER stress response) cells or in Atg7(-/-) cells. The protective effects of osteocalcin were nullified by suppression of Akt, mammalian target of rapamycin (mTOR) or nuclear factor kappa B (NFκB), suggesting that osteocalcin inhibits autophagy, ER stress and improves insulin signaling in the vascular tissue and cells under insulin resistance in a NFκB-dependent manner, which may be a promising therapeutic strategies of cardiovascular dysfunction secondary to obesity.

  10. A Novel Mammary Fat Pad Transplantation Technique to Visualize the Vessel Generation of Vascular Endothelial Stem Cells.

    Science.gov (United States)

    Yu, Qing Cissy; Song, Wenqian; Lai, Dengwen; Zeng, Yi Arial

    2017-08-03

    Endothelial cells (ECs) are the fundamental building blocks of the vascular architecture and mediate vascular growth and remodeling to ensure proper vessel development and homeostasis. However, studies on endothelial lineage hierarchy remain elusive due to the lack of tools to gain access as well as to directly evaluate their behavior in vivo. To address this shortcoming, a new tissue model to study angiogenesis using the mammary fat pad has been developed. The mammary gland develops mostly in the postnatal stages, including puberty and pregnancy, during which robust epithelium proliferation is accompanied by extensive vascular remodeling. Mammary fat pads provide space, matrix, and rich angiogenic stimuli from the growing mammary epithelium. Furthermore, mammary fat pads are located outside the peritoneal cavity, making them an easily accessible grafting site for assessing the angiogenic potential of exogenous cells. This work also describes an efficient tracing approach using fluorescent reporter mice to specifically label the targeted population of vascular endothelial stem cells (VESCs) in vivo. This lineage tracing method, coupled with subsequent tissue whole-mount microscopy, enable the direct visualization of targeted cells and their descendants, through which the proliferation capability can be quantified and the differentiation commitment can be fate-mapped. Using these methods, a population of bipotent protein C receptor (Procr) expressing VESCs has recently been identified in multiple vascular systems. Procr + VESCs, giving rise to both new ECs and pericytes, actively contribute to angiogenesis during development, homeostasis, and injury repair. Overall, this manuscript describes a new mammary fat pad transplantation and in vivo lineage tracing techniques that can be used to evaluate the stem cell properties of VESCs.

  11. Microparticle Shedding by Erythrocytes, Monocytes and Vascular Smooth Muscular Cells Is Reduced by Aspirin in Diabetic Patients.

    Science.gov (United States)

    Chiva-Blanch, Gemma; Suades, Rosa; Padró, Teresa; Vilahur, Gemma; Peña, Esther; Ybarra, Juan; Pou, Jose M; Badimon, Lina

    2016-07-01

    Diabetes mellitus is associated with an enhanced risk for cardiovascular disease and its prevalence is increasing. Diabetes induces metabolic stress on blood and vascular cells, promoting platelet activation and vascular dysfunction. The level of vascular cell activation can be measured by the number and phenotype of microparticles found in the circulation. The aim of this study was to investigate the effect of a platelet-inhibitory dose of aspirin on the number and type of microparticles shed to the circulation. Forty-three diabetic patients were enrolled in the study and received a daily dose of 100mg of aspirin for 10 days to cover the average platelet life-span in the circulation. Before and after the intervention period, circulating microparticles were characterized and quantified by flow cytometry. Type 1 diabetic patients had about twice the number of tissue factor-positive circulating microparticles (derived both from platelets and monocytes) and endothelial-derived E-selectin positive microparticles than type 2 diabetic patients. Aspirin therapy significantly inhibited platelets since cyclooxygenase 1 derived thromboxane generation levels were reduced by 99%. Microparticles derived from erythrocytes, activated monocytes, and smooth muscle cells were significantly reduced after 10 days of aspirin administration. These results indicate that: a) vascular and blood cells in type 1 diabetic patients are exposed to more sustained stress shown by their specific microparticle origin and levels; b) aspirin therapy inhibits vascular wall cell activation and microparticle shedding, and c) the effects of aspirin are similar in type 1 and 2 diabetes. Copyright © 2016 Sociedad Española de Cardiología. Published by Elsevier España, S.L.U. All rights reserved.

  12. Differential TCR signals for T helper cell programming.

    Science.gov (United States)

    Morel, Penelope A

    2018-05-02

    Upon encounter with their cognate antigen naïve CD4 T cells become activated and are induced to differentiate into several possible T helper (Th) cell subsets. This differentiation depends on a number of factors including antigen presenting cells, cytokines and costimulatory molecules. The strength of the T cell receptor (TCR) signal, related to the affinity of TCR for antigen and antigen dose, has emerged as a dominant factor in determining Th cell fate. Recent studies have revealed that TCR signals of high or low strength do not simply induce quantitatively different signals in the T cells, but rather qualitatively distinct pathways can be induced based on TCR signal strength. This review examines the recent literature in this area and highlights important new developments in our understanding of Th cell differentiation and TCR signal strength. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  13. In Vitro Generation of Vascular Wall-Resident Multipotent Stem Cells of Mesenchymal Nature from Murine Induced Pluripotent Stem Cells

    Directory of Open Access Journals (Sweden)

    Jennifer Steens

    2017-04-01

    Full Text Available Summary: The vascular wall (VW serves as a niche for mesenchymal stem cells (MSCs. In general, tissue-specific stem cells differentiate mainly to the tissue type from which they derive, indicating that there is a certain code or priming within the cells as determined by the tissue of origin. Here we report the in vitro generation of VW-typical MSCs from induced pluripotent stem cells (iPSCs, based on a VW-MSC-specific gene code. Using a lentiviral vector expressing the so-called Yamanaka factors, we reprogrammed tail dermal fibroblasts from transgenic mice containing the GFP gene integrated into the Nestin-locus (NEST-iPSCs to facilitate lineage tracing after subsequent MSC differentiation. A lentiviral vector expressing a small set of recently identified human VW-MSC-specific HOX genes then induced MSC differentiation. This direct programming approach successfully mediated the generation of VW-typical MSCs with classical MSC characteristics, both in vitro and in vivo. : In this article, Klein and colleagues show that iPSCs generated from skin fibroblasts of transgenic mice carrying a GFP gene under the control of the endogenous Nestin promoter to facilitate lineage tracing (NEST-iPSCs can be directly programmed toward mouse vascular wall-typical multipotent mesenchymal stem cells (VW-MSC by ectopic lentiviral expression of a previously defined VW-MSC-specific HOX code. Keywords: vascular wall-derived mesenchymal stem cells, HOX gene, induced pluripotent stem cells, direct programming, nestin

  14. Signal Transduction of Sphingosine-1-Phosphate G Protein—Coupled Receptors

    Directory of Open Access Journals (Sweden)

    Nicholas Young

    2006-01-01

    Full Text Available Sphingosine-1-phosphate (S1P is a bioactive lipid capable of eliciting dramatic effects in a variety of cell types. Signaling by this molecule is by a family of five G protein—coupled receptors named S1P1–5 that signal through a variety of pathways to regulate cell proliferation, migration, cytoskeletal organization, and differentiation. These receptors are expressed in a wide variety of tissues and cell types, and their cellular effects contribute to important biological and pathological functions of S1P in many processes, including angiogenesis, vascular development, lymphocyte trafficking, and cancer. This review will focus on the current progress in the field of S1P receptor signaling and biology.

  15. Trkb signaling in pericytes is required for cardiac microvessel stabilization.

    Directory of Open Access Journals (Sweden)

    Agustin Anastasia

    Full Text Available Pericyte and vascular smooth muscle cell (SMC recruitment to the developing vasculature is an important step in blood vessel maturation. Brain-derived neurotrophic factor (BDNF, expressed by endothelial cells, activates the receptor tyrosine kinase TrkB to stabilize the cardiac microvasculature in the perinatal period. However, the effects of the BDNF/TrkB signaling on pericytes/SMCs and the mechanisms downstream of TrkB that promote vessel maturation are unknown. To confirm the involvement of TrkB in vessel maturation, we evaluated TrkB deficient (trkb (-/- embryos and observed severe cardiac vascular abnormalities leading to lethality in late gestation to early prenatal life. Ultrastructural analysis demonstrates that trkb(-/- embryos exhibit defects in endothelial cell integrity and perivascular edema. As TrkB is selectively expressed by pericytes and SMCs in the developing cardiac vasculature, we generated mice deficient in TrkB in these cells. Mice with TrkB deficiency in perivascular cells exhibit reduced pericyte/SMC coverage of the cardiac microvasculature, abnormal endothelial cell ultrastructure, and increased vascular permeability. To dissect biological actions and the signaling pathways downstream of TrkB in pericytes/SMCs, human umbilical SMCs were treated with BDNF. This induced membranous protrusions and cell migration, events dependent on myosin light chain phosphorylation. Moreover, inhibition of Rho GTPase and the Rho-associated protein kinase (ROCK prevented membrane protrusion and myosin light chain phosphorylation in response to BDNF. These results suggest an important role for BDNF in regulating migration of TrkB-expressing pericytes/SMCs to promote cardiac blood vessel ensheathment and functional integrity during development.

  16. Essential role of TGF-beta/Smad pathway on statin dependent vascular smooth muscle cell regulation.

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    Juan Rodríguez-Vita

    Full Text Available BACKGROUND: The 3-hydroxy-3-methylglutaryl CoA reductase inhibitors (also called statins exert proven beneficial effects on cardiovascular diseases. Recent data suggest a protective role for Transforming Growth Factor-beta (TGF-beta in atherosclerosis by regulating the balance between inflammation and extracellular matrix accumulation. However, there are no studies about the effect of statins on TGF-beta/Smad pathway in atherosclerosis and vascular cells. METHODOLOGY: In cultured vascular smooth muscle cells (VSMCs statins enhanced Smad pathway activation caused by TGF-beta. In addition, statins upregulated TGF-beta receptor type II (TRII, and increased TGF-beta synthesis and TGF-beta/Smad-dependent actions. In this sense, statins, through Smad activation, render VSMCs more susceptible to TGF-beta induced apoptosis and increased TGF-beta-mediated ECM production. It is well documented that high doses of statins induce apoptosis in cultured VSMC in the presence of serum; however the precise mechanism of this effect remains to be elucidated. We have found that statins-induced apoptosis was mediated by TGF-beta/Smad pathway. Finally, we have described that RhoA inhibition is a common intracellular mechanisms involved in statins effects. The in vivo relevance of these findings was assessed in an experimental model of atherosclerosis in apolipoprotein E deficient mice: Treatment with Atorvastatin increased Smad3 phosphorylation and TRII overexpression, associated to elevated ECM deposition in the VSMCs within atheroma plaques, while apoptosis was not detected. CONCLUSIONS: Statins enhance TGF-beta/Smad pathway, regulating ligand levels, receptor, main signaling pathway and cellular responses of VSMC, including apoptosis and ECM accumulation. Our findings show that TGF-beta/Smad pathway is essential for statins-dependent actions in VSMCs.

  17. PDGF activates K-Cl cotransport through phosphoinositide 3-kinase and protein phosphatase-1 in primary cultures of vascular smooth muscle cells.

    Science.gov (United States)

    Zhang, Jing; Lauf, Peter K; Adragna, Norma C

    2005-07-15

    K-Cl cotransport (K-Cl COT, KCC) is an electroneutrally coupled movement of K and Cl present in most cells. In this work, we studied the pathways of regulation of K-Cl COT by platelet-derived growth factor (PDGF) in primary cultures of vascular smooth muscle cells (VSMCs). Wortmannin and LY 294002 blocked the PDGF-induced K-Cl COT activation, indicating that the phosphoinositide 3-kinase (PI 3-K) pathway is involved. However, PD 98059 had no effect on K-Cl COT activation by PDGF, suggesting that the mitogen-activated protein kinase pathway is not involved under the experimental conditions tested. Involvement of phosphatases was also examined. Sodium orthovanadate, cyclosporin A and okadaic acid had no effect on PDGF-stimulated K-Cl COT. Calyculin A blocked the PDGF-stimulated K-Cl COT by 60%, suggesting that protein phosphatase-1 (PP-1) is a mediator in the PDGF signaling pathway/s. In conclusion, our results indicate that the PDGF-mediated pathways of K-Cl COT regulation involve the signaling molecules PI 3-K and PP-1.

  18. Platelets Promote Metastasis via Binding Tumor CD97 Leading to Bidirectional Signaling that Coordinates Transendothelial Migration

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    Yvona Ward

    2018-04-01

    Full Text Available Summary: Tumor cells initiate platelet activation leading to the secretion of bioactive molecules, which promote metastasis. Platelet receptors on tumors have not been well-characterized, resulting in a critical gap in knowledge concerning platelet-promoted metastasis. We identify a direct interaction between platelets and tumor CD97 that stimulates rapid bidirectional signaling. CD97, an adhesion G protein-coupled receptor (GPCR, is an overexpressed tumor antigen in several cancer types. Purified CD97 extracellular domain or tumor cell-associated CD97 stimulated platelet activation. CD97-initiated platelet activation led to granule secretion, including the release of ATP, a mediator of endothelial junction disruption. Lysophosphatidic acid (LPA derived from platelets induced tumor invasiveness via proximal CD97-LPAR heterodimer signaling, coupling coincident tumor cell migration and vascular permeability to promote transendothelial migration. Consistent with this, CD97 was necessary for tumor cell-induced vascular permeability in vivo and metastasis formation in preclinical models. These findings support targeted blockade of tumor CD97 as an approach to ameliorate metastatic spread. : Tumor-initiated platelet activation promotes tissue invasion of cancer cells and metastasis. Ward et al. demonstrate that a common tumor-associated antigen, CD97, accounts for platelet activation and participates directly in LPA-mediated signal transduction leading to tumor cell invasion. CD97 promotes vascular extravasation and metastasis in pre-clinical models. Keywords: platelets, metastasis, transendothelial migration, circulating tumor cells, CD97, adhesion GPCR, LPA

  19. Bioengineering vascularized tissue constructs using an injectable cell-laden enzymatically crosslinked collagen hydrogel derived from dermal extracellular matrix.

    Science.gov (United States)

    Kuo, Kuan-Chih; Lin, Ruei-Zeng; Tien, Han-Wen; Wu, Pei-Yun; Li, Yen-Cheng; Melero-Martin, Juan M; Chen, Ying-Chieh

    2015-11-01

    Tissue engineering promises to restore or replace diseased or damaged tissue by creating functional and transplantable artificial tissues. The development of artificial tissues with large dimensions that exceed the diffusion limitation will require nutrients and oxygen to be delivered via perfusion instead of diffusion alone over a short time period. One approach to perfusion is to vascularize engineered tissues, creating a de novo three-dimensional (3D) microvascular network within the tissue construct. This significantly shortens the time of in vivo anastomosis, perfusion and graft integration with the host. In this study, we aimed to develop injectable allogeneic collagen-phenolic hydroxyl (collagen-Ph) hydrogels that are capable of controlling a wide range of physicochemical properties, including stiffness, water absorption and degradability. We tested whether collagen-Ph hydrogels could support the formation of vascularized engineered tissue graft by human blood-derived endothelial colony-forming cells (ECFCs) and bone marrow-derived mesenchymal stem cells (MSC) in vivo. First, we studied the growth of adherent ECFCs and MSCs on or in the hydrogels. To examine the potential formation of functional vascular networks in vivo, a liquid pre-polymer solution of collagen-Ph containing human ECFCs and MSCs, horseradish peroxidase and hydrogen peroxide was injected into the subcutaneous space or abdominal muscle defect of an immunodeficient mouse before gelation, to form a 3D cell-laden polymerized construct. These results showed that extensive human ECFC-lined vascular networks can be generated within 7 days, the engineered vascular density inside collagen-Ph hydrogel constructs can be manipulated through refinable mechanical properties and proteolytic degradability, and these networks can form functional anastomoses with the existing vasculature to further support the survival of host muscle tissues. Finally, optimized conditions of the cell-laden collagen

  20. Vascular-targeted therapies for Duchenne muscular dystrophy

    Science.gov (United States)

    2013-01-01

    Duchenne muscular dystrophy (DMD) is the most common muscular dystrophy and an X-linked recessive, progressive muscle wasting disease caused by the absence of a functional dystrophin protein. Dystrophin has a structural role as a cytoskeletal stabilization protein and protects cells against contraction-induced damage. Dystrophin also serves a signaling role through mechanotransduction of forces and localization of neuronal nitric oxide synthase (nNOS), which produces nitric oxide (NO) to facilitate vasorelaxation. In DMD, the signaling defects produce inadequate tissue perfusion caused by functional ischemia due to a diminished ability to respond to shear stress induced endothelium-dependent dilation. Additionally, the structural defects seen in DMD render myocytes with an increased susceptibility to mechanical stress. The combination of both defects is necessary to generate myocyte damage, which induces successive rounds of myofiber degeneration and regeneration, loss of calcium homeostasis, chronic inflammatory response, fibrosis, and myonecrosis. In individuals with DMD, these processes inevitably cause loss of ambulation shortly after the first decade and an abbreviated life with death in the third or fourth decade due to cardio-respiratory anomalies. There is no known cure for DMD, and although the culpable gene has been identified for more than twenty years, research on treatments has produced few clinically relevant results. Several recent studies on novel DMD therapeutics are vascular targeted and focused on attenuating the inherent functional ischemia. One approach improves vasorelaxation capacity through pharmaceutical inhibition of either phosphodiesterase 5 (PDE5) or angiotensin-converting enzyme (ACE). Another approach increases the density of the underlying vascular network by inducing angiogenesis, and this has been accomplished through either direct delivery of vascular endothelial growth factor (VEGF) or by downregulating the VEGF decoy

  1. Cues for cellular assembly of vascular elastin networks

    Science.gov (United States)

    Kothapalli, Chandrasekhar R.

    Elastin, a structural protein distributed in the extracellular matrix of vascular tissues is critical to the maintenance of vascular mechanics, besides regulation of cell-signaling pathways involved in injury response and morphogenesis. Thus, congenital absence or disease-mediated degradation of vascular elastin and its malformation within native vessels due to innately poor elastin synthesis by adult vascular cells compromise vascular homeostasis. Current elastin regenerative strategies using tissue engineering principles are limited by the progressive destabilization of tropoelastin mRNA expression in adult vascular cells and the unavailability of scaffolds that can provide cellular cues necessary to up-regulate elastin synthesis and regenerate faithful mimics of native elastin. Since our earlier studies demonstrated the elastogenic utility of hyaluronan (HA)-based cues, we have currently sought to identify a unique set of culture conditions based on HA fragments (0.756-2000 kDa), growth factors (TGF-beta1, IGF-1) and other biomolecules (Cu2+ ions, LOX), which will together enhance synthesis, crosslinking, maturation and fibrous elastin matrix formation by adult SMCs, under both healthy and inflammatory conditions. It was observed that TGF-beta1 (1 ng/mL) together with HA oligomers (0.2 microg/mL) synergistically suppressed SMC proliferation, enhanced tropoelastin (8-fold) and matrix elastin synthesis (5.5-fold), besides improving matrix yield (4.5-fold), possibly by increasing production and activity of lysyl oxidase (LOX). Though addition of IGF-1 alone did not offer any advantage, HA fragments (20-200 kDa) in the presence of IGF-1 stimulated tropoelastin and soluble elastin synthesis more than 2.2-fold, with HMW HA contributing for ˜5-fold increase in crosslinked matrix elastin synthesis. Similarly, 0.1 M of Cu2+ ions, alone or together with HA fragments stimulated synthesis of tropoelastin (4-fold) and crosslinked matrix elastin (4.5-fold), via increases in

  2. Harmful effects of the azathioprine metabolite 6-mercaptopurine in vascular cells: induction of mineralization.

    Science.gov (United States)

    Prüfer, Jasmin; Schuchardt, Mirjam; Tölle, Markus; Prüfer, Nicole; Höhne, Matthias; Zidek, Walter; van der Giet, Markus

    2014-01-01

    Vascular mineralization contributes to the high cardiovascular morbidity and mortality in patients who suffer from chronic kidney disease and in individuals who have undergone solid organ transplantation. The immunosuppressive regimen used to treat these patients appears to have an impact on vascular alterations. The effect of 6-mercaptopurine (6-MP) on vascular calcification has not yet been determined. This study investigates the effect of 6-MP on vascular mineralization by the induction of trans-differentiation of rat vascular smooth muscle cells in vitro. 6-MP not only induces the expression of osteo-chondrocyte-like transcription factors and proteins but also activates alkaline phosphatase enzyme activity and produces calcium deposition in in vitro and ex vivo models. These processes are dependent on 6-MP-induced production of reactive oxygen species, intracellular activation of mitogen-activated kinases and phosphorylation of the transcription factor Cbfa1. Furthermore, the metabolic products of 6-MP, 6-thioguanine nucleotides and 6-methyl-thio-inosine monophosphate have major impacts on cellular calcification. These data provide evidence for a possible harmful effect of the immunosuppressive drug 6-MP in vascular diseases, such as arteriosclerosis.

  3. Harmful effects of the azathioprine metabolite 6-mercaptopurine in vascular cells: induction of mineralization.

    Directory of Open Access Journals (Sweden)

    Jasmin Prüfer

    Full Text Available Vascular mineralization contributes to the high cardiovascular morbidity and mortality in patients who suffer from chronic kidney disease and in individuals who have undergone solid organ transplantation. The immunosuppressive regimen used to treat these patients appears to have an impact on vascular alterations. The effect of 6-mercaptopurine (6-MP on vascular calcification has not yet been determined. This study investigates the effect of 6-MP on vascular mineralization by the induction of trans-differentiation of rat vascular smooth muscle cells in vitro. 6-MP not only induces the expression of osteo-chondrocyte-like transcription factors and proteins but also activates alkaline phosphatase enzyme activity and produces calcium deposition in in vitro and ex vivo models. These processes are dependent on 6-MP-induced production of reactive oxygen species, intracellular activation of mitogen-activated kinases and phosphorylation of the transcription factor Cbfa1. Furthermore, the metabolic products of 6-MP, 6-thioguanine nucleotides and 6-methyl-thio-inosine monophosphate have major impacts on cellular calcification. These data provide evidence for a possible harmful effect of the immunosuppressive drug 6-MP in vascular diseases, such as arteriosclerosis.

  4. Proline-rich tyrosine kinase 2 (Pyk2) mediates vascular endothelial-cadherin-based cell-cell adhesion by regulating beta-catenin tyrosine phosphorylation

    NARCIS (Netherlands)

    van Buul, Jaap D.; Anthony, Eloise C.; Fernandez-Borja, Mar; Burridge, Keith; Hordijk, Peter L.

    2005-01-01

    Vascular endothelial-cadherin (VE-cadherin) controls endothelial cell-cell adhesion and preserves endothelial integrity. In order to maintain endothelial barrier function, VE-cadherin function is tightly regulated through mechanisms that involve protein phosphorylation and cytoskeletal dynamics.

  5. Color Doppler Ultrasonographic Findings of Vascular Leiomyoma: Pathologic Correlation

    Energy Technology Data Exchange (ETDEWEB)

    Ko, Ji Young; Koh, Sung Hye; Min, Soo Kee; Choi, A Lam; Jang, Kyung Mi; Lee, Yul; Lee, Kwan Seop; Lee, Hyun; Sohn, Jeong Hee [Hallym University Sacred Heart Hospital, Anyang (Korea, Republic of); Kim, Sam Soo [Kangwon National University College of Medicine, Chuncheon (Korea, Republic of)

    2009-12-15

    To evaluate the distribution of color flow signals on color Doppler ultrasonography of vascular leiomyomas and to correlate them with pathologic findings. We retrospectively analyzed color Doppler ultrasonographic images and pathologic slides of six vascular leiomyomas. We classified the patterns of distribution of color flow signals into localized compact cluster types and non-cluster types, and the pathologic findings into three subtypes: solid, venous and cavernous. All cases showed well-defined homogenous hypoechoic subcutaneous masses on gray-scale ultrasonography. Three cases showed localized compact cluster types on color Doppler ultrasonography, one in each subtype (solid, venous and cavernous). For the three non-cluster types, again there was on in each subtype. In addition, on pathologic analysis the zone of the localized compact cluster of color flow signals coincided with a cluster of larger, vascular caliber masses. Localized compact clusters of color flow signals on color Doppler ultrasonography were seen in 50% of our cases and correlated with a cluster of larger vascular caliber in the mass. But the pattern of distribution of color flows didn't show a correlation with pathologic type

  6. Color Doppler Ultrasonographic Findings of Vascular Leiomyoma: Pathologic Correlation

    International Nuclear Information System (INIS)

    Ko, Ji Young; Koh, Sung Hye; Min, Soo Kee; Choi, A Lam; Jang, Kyung Mi; Lee, Yul; Lee, Kwan Seop; Lee, Hyun; Sohn, Jeong Hee; Kim, Sam Soo

    2009-01-01

    To evaluate the distribution of color flow signals on color Doppler ultrasonography of vascular leiomyomas and to correlate them with pathologic findings. We retrospectively analyzed color Doppler ultrasonographic images and pathologic slides of six vascular leiomyomas. We classified the patterns of distribution of color flow signals into localized compact cluster types and non-cluster types, and the pathologic findings into three subtypes: solid, venous and cavernous. All cases showed well-defined homogenous hypoechoic subcutaneous masses on gray-scale ultrasonography. Three cases showed localized compact cluster types on color Doppler ultrasonography, one in each subtype (solid, venous and cavernous). For the three non-cluster types, again there was on in each subtype. In addition, on pathologic analysis the zone of the localized compact cluster of color flow signals coincided with a cluster of larger, vascular caliber masses. Localized compact clusters of color flow signals on color Doppler ultrasonography were seen in 50% of our cases and correlated with a cluster of larger vascular caliber in the mass. But the pattern of distribution of color flows didn't show a correlation with pathologic type

  7. Biomarkers of drug-induced vascular injury

    International Nuclear Information System (INIS)

    Brott, D.; Gould, S.; Jones, H.; Schofield, J.; Prior, H.; Valentin, J.P; Bjurstrom, S.; Kenne, K.; Schuppe-Koistinen, I.; Katein, A.; Foster-Brown, L.; Betton, G.; Richardson, R.; Evans, G.; Louden, C.

    2005-01-01

    In pre-clinical safety studies, drug-induced vascular injury is an issue of concern because there are no obvious diagnostic markers for pre-clinical or clinical monitoring and there is an intellectual gap in our understanding of the pathogenesis of this lesion. While vasodilatation and increased shear stress appear to play a role, the exact mechanism(s) of injury to the primary targets, smooth muscle and endothelial cells are unknown. However, evaluation of novel markers for potential clinical monitoring with a mechanistic underpinning would add value in risk assessment and management. This mini review focuses on the progress to identify diagnostic markers of drug-induced vascular injury. Von Willebrand factor (vWF), released upon perturbation of endothelial cells, is transiently increased in plasma prior to morphological evidence of damage in dogs or rats treated with vascular toxicants. Therefore, vWF might be a predictive biomarker of vascular injury. However, vWF is not an appropriate biomarker of lesion progression or severity since levels return to baseline values when there is morphological evidence of injury. A potential mechanistically linked biomarker of vascular injury is caveolin-1. Expression of this protein, localized primarily to smooth muscle and endothelial cells, decreases with the onset of vascular damage. Since vascular injury involves multiple mediators and cell types, evaluation of a panel rather than a single biomarker may be more useful in monitoring early and severe progressive vascular injury

  8. KCl cotransport regulation and protein kinase G in cultured vascular smooth muscle cells.

    Science.gov (United States)

    Adragna, N C; Zhang, J; Di Fulvio, M; Lincoln, T M; Lauf, P K

    2002-05-15

    K-Cl cotransport is activated by vasodilators in erythrocytes and vascular smooth muscle cells and its regulation involves putative kinase/phosphatase cascades. N-ethylmaleimide (NEM) activates the system presumably by inhibiting a protein kinase. Nitrovasodilators relax smooth muscle via cGMP-dependent activation of protein kinase G (PKG), a regulator of membrane channels and transporters. We investigated whether PKG regulates K-Cl cotransport activity or mRNA expression in normal, PKG-deficient-vector-only-transfected (PKG-) and PKG-catalytic-domain-transfected (PKG+) rat aortic smooth muscle cells. K-Cl cotransport was calculated as the Cl-dependent Rb influx, and mRNA was determined by semiquantitative RT-PCR. Baseline K-Cl cotransport was higher in PKG+ than in PKG- cells (p <0.01). At 0.5 mM, NEM stimulated K-Cl cotransport by 5-fold in PKG- but not in PKG+ cells. However, NEM was more potent although less effective to activate K-Cl cotransport in normal (passage 1-3) and PKG+ than in PKG- cells. In PKG- cells, [(dihydroindenyl) oxy] alkanoic acid (300 mM) but not furosemide (1 mM) inhibited K-Cl cotransport. Furthermore, no difference in K-Cl cotransport mRNA expression was observed between these cells. In conclusion, this study shows that manipulation of PKG expression in vascular smooth muscle cells affects K-Cl cotransport activity and its activation by NEM.

  9. MIXED HYALINE VASCULAR AND PLASMA CELL TYPE CASTLEMAN’S DISEASE: REPORT OF A CASE

    Directory of Open Access Journals (Sweden)

    F. Asgarani

    2006-05-01

    Full Text Available Castleman’s disease (angiofollicular lymphoid hyperplasia includes a heterogeneous group of lymphoproliferative disorders. The cause of this disease remains uncertain. There are two types of localized Castleman’s disease: the more common hyaline vascular and the plasma cell types. Mixed variant is an uncommon localized lesion in general population. The lesions can occur in any part of the body that contains lymphoid tissue, although seventy percent are found in the anterior mediastinum. We report a thirty years old boy with Castleman’s disease who presented with fever, anorexia, weight loss,sweating, anemia and abdominal mass. The histologic examination of the biopsy specimens revealed a mixed hyaline vascular and plasma cell type of Castleman’s disease.

  10. Proatherogenic pathways leading to vascular calcification

    International Nuclear Information System (INIS)

    Mazzini, Michael J.; Schulze, P. Christian

    2006-01-01

    Cardiovascular disease is the leading cause of morbidity and mortality in the western world and atherosclerosis is the major common underlying disease. The pathogenesis of atherosclerosis involves local vascular injury, inflammation and oxidative stress as well as vascular calcification. Vascular calcification has long been regarded as a degenerative process leading to mineral deposition in the vascular wall characteristic for late stages of atherosclerosis. However, recent studies identified vascular calcification in early stages of atherosclerosis and its occurrence has been linked to clinical events in patients with cardiovascular disease. Its degree correlates with local vascular inflammation and with the overall impact and the progression of atherosclerosis. Over the last decade, diverse and highly regulated molecular signaling cascades controlling vascular calcification have been described. Local and circulating molecules such as osteopontin, osteoprogerin, leptin and matrix Gla protein were identified as critical regulators of vascular calcification. We here review the current knowledge on molecular pathways of vascular calcification and their relevance for the progression of cardiovascular disease

  11. Metal-free Phtalocyanine and 5-Aminolevulenic Acid in Photodynamic Treatment of Human Vascular Cells

    Science.gov (United States)

    Udartseva, Olga O.; Andreeva, Elena R.; Buravkova, Ludmila B.; Tararak, Eduard M.

    2010-05-01

    Originally developed as a tumor therapy, now photodynamic therapy (PDT) may become a useful tool for treatment of cardiovascular diseases. Different cell types are involved in this vascular pathology, and these cells possess different susceptibility to PDT. In this study we screened the effects of two new photosensitizers (PtS and ALA) on human vascular cells. Human macrophages (Mph), aorta endothelial (HAEC) and smooth muscle (SMC) cells were obtained and cultured as described elsewhere. 2-10 ug/ml PtS was added to culture medium 24 h before PDT. ALA was added in 2-10 mM concentration in serum-free culture medium. Then cells were washed carefully and illuminated with 692-nm (PtS) or 633-nm (ALA) light. Cellular viability was measured with MTT-test. Except the case of use 5-10 mM ALA, either photosensitizer accumulation alone or laser illumination alone did not affect cells. Illumination of PtS or ALA-loaded cells (1-20 J/cm2) impaired cellular viability in dose-dependent manner. LD90 for different vascular cells with PtS were as follows: HAEC -1 J/cm2, SMC -2 J/cm2, Mph -5 J/cm2. HAEC and some Mph were unsusceptible to ALA-PDT. SMC LD90 with ALA was 20 J/cm2. Effects of ALA-PDT depended on protoporphyrin IX (PpIX) formation in cells. HAEC didn't accumulate PpIX and were non-sensitive to ALA-PDT. PpIX formation in Mph changed individually according to donor. Illumination of ALA-loaded Mph with low PpIX formation did not affect cells. However LD90 for Mph with high PpIX formation comprised 20 J/cm2. All cell types were more susceptible to PtS-PDT compared to ALA-PDT. Among tested photosensitizers PtS was the most effective one. HAEC were the most susceptible to PtS-PDT.

  12. Alpha1a-Adrenoceptor Genetic Variant Triggers Vascular Smooth Muscle Cell Hyperproliferation and Agonist Induced Hypertrophy via EGFR Transactivation Pathway.

    Directory of Open Access Journals (Sweden)

    Irina Gradinaru

    Full Text Available α1a Adrenergic receptors (α1aARs are the predominant AR subtype in human vascular smooth muscle cells (SMCs. α1aARs in resistance vessels are crucial in the control of blood pressure, yet the impact of naturally occurring human α1aAR genetic variants in cardiovascular disorders remains poorly understood. To this end, we present novel findings demonstrating that 3D cultures of vascular SMCs expressing human α1aAR-247R (247R genetic variant demonstrate significantly increased SMC contractility compared with cells expressing the α1aAR-WT (WT receptor. Stable expression of 247R genetic variant also triggers MMP/EGFR-transactivation dependent serum- and agonist-independent (constitutive hyperproliferation and agonist-dependent hypertrophy of SMCs. Agonist stimulation reduces contractility Using pathway-specific inhibitors we determined that the observed hyperproliferation of 247R-expressing cells is triggered via β-arrestin1/Src/MMP-2/EGFR/ERK-dependent mechanism. MMP-2-specific siRNA inhibited 247R-triggered hyperproliferation indicating MMP-2 involvement in 247R-triggered hyperproliferation in SMCs. β-arrestin1-specific shRNA also inhibited 247R-triggered hyperproliferation but did not affect hypertrophy in 247R-expressing SMCs, indicating that agonist-dependent hypertrophy is independent of β-arrestin1. Our data reveal that in different cardiovascular cells the same human receptor genetic variant can activate alternative modulators of the same signaling pathway. Thus, our findings in SMCs demonstrate that depending on the type of cells expressing the same receptor (or receptor variant, different target-specific inhibitors could be used to modulate aberrant hyperproliferative or hypertrophic pathways in order to restore normal phenotype.

  13. Leptin promotes osteoblast differentiation and mineralization of primary cultures of vascular smooth muscle cells by inhibiting glycogen synthase kinase (GSK)-3{beta}

    Energy Technology Data Exchange (ETDEWEB)

    Zeadin, Melec G.; Butcher, Martin K.; Shaughnessy, Stephen G. [Department of Medicine, McMaster University, Hamilton, ON (Canada); Thrombosis and Atherosclerosis Research Institute, Hamilton, ON (Canada); Werstuck, Geoff H., E-mail: Geoff.Werstuck@taari.ca [Department of Medicine, McMaster University, Hamilton, ON (Canada); Thrombosis and Atherosclerosis Research Institute, Hamilton, ON (Canada)

    2012-09-07

    Highlights: Black-Right-Pointing-Pointer Leptin promotes osteoblast differentiation of primary smooth muscle cells. Black-Right-Pointing-Pointer Leptin regulates the expression of genes involved in osteoblast differentiation. Black-Right-Pointing-Pointer Constitutively active GSK-3{beta} attenuates leptin-induced osteoblast differentiation. Black-Right-Pointing-Pointer This suggests that leptin signals through GSK-3{beta} to promote osteoblast differentiation. -- Abstract: In this study, we begin to investigate the underlying mechanism of leptin-induced vascular calcification. We found that treatment of cultured bovine aortic smooth muscle cells (BASMCs) with leptin (0.5-4 {mu}g/ml) induced osteoblast differentiation in a dose-dependent manner. Furthermore, we found that leptin significantly increased the mRNA expression of osteopontin and bone sialoprotein, while down-regulating matrix gla protein (MGP) expression in BASMCs. Key factors implicated in osteoblast differentiation, including members of the Wnt signaling pathway, were examined. Exposure to leptin enhanced phosphorylation of GSK-3{beta} on serine-9 thereby inhibiting activity and promoting the nuclear accumulation of {beta}-catenin. Transfection of BASMCs with an adenovirus that expressed constitutively active GSK-3{beta} (Ad-GSK-3{beta} S9A) resulted in a >2-fold increase in GSK-3{beta} activity and a significant decrease in leptin-induced alkaline phosphatase (ALP) activity. In addition, qRT-PCR analysis showed that GSK-3{beta} activation resulted in a significant decrease in the expression of osteopontin and bone sialoprotein, but a marked increase in MGP mRNA expression. When taken together, our results suggest a mechanism by which leptin promotes osteoblast differentiation and vascular calcification in vivo.

  14. Inhibition of TGF-β Signaling in SHED Enhances Endothelial Differentiation.

    Science.gov (United States)

    Xu, J G; Gong, T; Wang, Y Y; Zou, T; Heng, B C; Yang, Y Q; Zhang, C F

    2018-02-01

    Low efficiency of deriving endothelial cells (ECs) from adult stem cells hampers their utilization in tissue engineering studies. The purpose of this study was to investigate whether suppression of transforming growth factor beta (TGF-β) signaling could enhance the differentiation efficiency of dental pulp-derived stem cells into ECs. We initially used vascular endothelial growth factor A (VEGF-A) to stimulate 2 dental pulp-derived stem cells (dental pulp stem cells and stem cells from human exfoliated deciduous teeth [SHED]) and compared their differentiation capacity into ECs. We further evaluated whether the vascular endothelial growth factor receptor I (VEGF-RI)-specific ligand placental growth factor-1 (PlGF-1) could mediate endothelial differentiation. Finally, we investigated whether the TGF-β signaling inhibitor SB-431542 could enhance the inductive effect of VEGF-A on endothelial differentiation, as well as the underlying mechanisms involved. ECs differentiated from dental pulp-derived stem cells exhibited the typical phenotypes of primary ECs, with SHED possessing a higher endothelial differentiation potential than dental pulp stem cells. VEGFR1-specific ligand-PLGF exerted a negligible effect on SHED-ECs differentiation. Compared with VEGF-A alone, the combination of VEGF-A and SB-431542 significantly enhanced the endothelial differentiation of SHED. The presence of SB-431542 inhibited the phosphorylation of Suppressor of Mothers Against Decapentaplegic 2/3 (SMAD2/3), allowing for VEGF-A-dependent phosphorylation and upregulation of VEGFR2. Our results indicate that the combination of VEGF-A and SB-431542 could enhance the differentiation of dental pulp-derived stem cells into endothelial cells, and this process is mediated through enhancement of VEGF-A-VEGFR2 signaling and concomitant inhibition of TGF-β-SMAD2/3 signaling.

  15. Effect of benzo[a]pyrene on the production of vascular endothelial growth factor by human eosinophilic leukemia EoL-1 cells.

    Science.gov (United States)

    Gu, Jie; Chan, Lai-Sheung; Wong, Chris Kong-Chu; Wong, Ngok-Shun; Wong, Chun-Kwok; Leung, Kok-Nam; Mak, Naiki K

    2011-01-01

    Benzo[a]pyrene (BaP) has been shown to affect both the development and response of T and B cells in the immune system. However, the effect of BaP on other immune cells, such as eosionophils, is unknown. In this study, we investigated the effect of BaP on the production of vascular endothelial growth factor (VEGF) using an in vitro eosinophilic EoL-1 cell and human umbilical vein endothelial cell (HUVEC) co-culture system. EoL-1-conditioned medium was found to promote the growth of HUVEC in a time-dependent manner. The growth stimulating activity was due to the production of VEGF by the EoL-1 cells. The production of VEGF was correlated with the enhanced expression of the phosphorylated form of extracellular signal-regulated kinases (p-ERKs) and the upregulated expression of VEGF mRNA. Furthermore, BaP-induced expression of VEGF mRNA was reduced by the ERK inhibitor PD98059. Results from this study suggested that BaP might affect the growth of endothelial cells through the modulation of VEGF production by eosinophils.

  16. Efficient Direct Reprogramming of Mature Amniotic Cells into Endothelial Cells by ETS Factors and TGFβ Suppression

    Science.gov (United States)

    Ginsberg, Michael; James, Daylon; Ding, Bi-Sen; Nolan, Daniel; Geng, Fuqiang; Butler, Jason M; Schachterle, William; Pulijaal, Venkat R; Mathew, Susan; Chasen, Stephen T; Xiang, Jenny; Rosenwaks, Zev; Shido, Koji; Elemento, Olivier; Rabbany, Sina Y; Rafii, Shahin

    2012-01-01

    ETS transcription factors ETV2, FLI1 and ERG1 specify pluripotent stem cells into endothelial cells (ECs). However, these ECs are unstable and drift towards non-vascular cell fates. We show that human mid-gestation c-Kit− lineage-committed amniotic cells (ACs) can be readily reprogrammed into induced vascular endothelial cells (iVECs). Transient ETV2 expression in ACs generated proliferative but immature iVECs, while co-expression with FLI1/ERG1 endowed iVECs with a vascular repertoire and morphology matching mature stable ECs. Brief TGFβ-inhibition functionalized VEGFR2 signaling, augmenting specification of ACs to iVECs. Genome-wide transcriptional analyses showed that iVECs are similar to adult ECs in which vascular-specific genes are turned on and non-vascular genes are silenced. Functionally, iVECs form long-lasting patent vasculature in Matrigel plugs and regenerating livers. Thus, short-term ETV2 expression and TGFβ-inhibition along with constitutive ERG1/FLI1 co-expression reprogram mature ACs into durable and functional iVECs with clinical-scale expansion potential. Public banking of HLA-typed iVECs would establish a vascular inventory for treatment of genetically diverse disorders. PMID:23084400

  17. YAP1 Regulates OCT4 Activity and SOX2 Expression to Facilitate Self-Renewal and Vascular Mimicry of Stem-Like Cells.

    Science.gov (United States)

    Bora-Singhal, Namrata; Nguyen, Jonathan; Schaal, Courtney; Perumal, Deepak; Singh, Sandeep; Coppola, Domenico; Chellappan, Srikumar

    2015-06-01

    Non-small cell lung cancer (NSCLC) is highly correlated with smoking and has very low survival rates. Multiple studies have shown that stem-like cells contribute to the genesis and progression of NSCLC. Our results show that the transcriptional coactivator yes-associated protein 1 (YAP1), which is the oncogenic component of the Hippo signaling pathway, is elevated in the stem-like cells from NSCLC and contributes to their self-renewal and ability to form angiogenic tubules. Inhibition of YAP1 by a small molecule or depletion of YAP1 by siRNAs suppressed self-renewal and vascular mimicry of stem-like cells. These effects of YAP1 were mediated through the embryonic stem cell transcription factor, Sox2. YAP1 could transcriptionally induce Sox2 through a physical interaction with Oct4; Sox2 induction occurred independent of TEAD2 transcription factor, which is the predominant mediator of YAP1 functions. The binding of Oct4 to YAP1 could be detected in cell lines as well as tumor tissues; the interaction was elevated in NSCLC samples compared to normal tissue as seen by proximity ligation assays. YAP1 bound to Oct4 through the WW domain, and a peptide corresponding to this region could disrupt the interaction. Delivery of the WW domain peptide to stem-like cells disrupted the interaction and abrogated Sox2 expression, self-renewal, and vascular mimicry. Depleting YAP1 reduced the expression of multiple epithelial-mesenchymal transition genes and prevented the growth and metastasis of tumor xenografts in mice; overexpression of Sox2 in YAP1 null cells rescued these functions. These results demonstrate a novel regulation of stem-like functions by YAP1, through the modulation of Sox2 expression. © 2015 AlphaMed Press.

  18. Bioprinting for vascular and vascularized tissue biofabrication.

    Science.gov (United States)

    Datta, Pallab; Ayan, Bugra; Ozbolat, Ibrahim T

    2017-03-15

    Bioprinting is a promising technology to fabricate design-specific tissue constructs due to its ability to create complex, heterocellular structures with anatomical precision. Bioprinting enables the deposition of various biologics including growth factors, cells, genes, neo-tissues and extra-cellular matrix-like hydrogels. Benefits of bioprinting have started to make a mark in the fields of tissue engineering, regenerative medicine and pharmaceutics. Specifically, in the field of tissue engineering, the creation of vascularized tissue constructs has remained a principal challenge till date. However, given the myriad advantages over other biofabrication methods, it becomes organic to expect that bioprinting can provide a viable solution for the vascularization problem, and facilitate the clinical translation of tissue engineered constructs. This article provides a comprehensive account of bioprinting of vascular and vascularized tissue constructs. The review is structured as introducing the scope of bioprinting in tissue engineering applications, key vascular anatomical features and then a thorough coverage of 3D bioprinting using extrusion-, droplet- and laser-based bioprinting for fabrication of vascular tissue constructs. The review then provides the reader with the use of bioprinting for obtaining thick vascularized tissues using sacrificial bioink materials. Current challenges are discussed, a comparative evaluation of different bioprinting modalities is presented and future prospects are provided to the reader. Biofabrication of living tissues and organs at the clinically-relevant volumes vitally depends on the integration of vascular network. Despite the great progress in traditional biofabrication approaches, building perfusable hierarchical vascular network is a major challenge. Bioprinting is an emerging technology to fabricate design-specific tissue constructs due to its ability to create complex, heterocellular structures with anatomical precision

  19. Growth hormone increases vascular cell adhesion molecule 1 expression

    DEFF Research Database (Denmark)

    Hansen, Troels Krarup; Fisker, Sanne; Dall, Rolf

    2004-01-01

    We investigated the impact of GH administration on endothelial adhesion molecules, vascular cell adhesion molecule-1 (VCAM-1) and E-selectin, in vivo and in vitro. Soluble VCAM-1, E-selectin, and C-reactive protein concentrations were measured before and after treatment in 25 healthy subjects...... and 25 adult GH-deficient (GHD) patients randomized to GH treatment or placebo. Furthermore, we studied the direct effect of GH and IGF-I and serum from GH-treated subjects on basal and TNF alpha-stimulated expression of VCAM-1 and E-selectin on cultured human umbilical vein endothelial cells. Baseline......% confidence interval: 95.0-208.7 microg/liter); P cells, there was no direct stimulatory effect of either GH or IGF-I on the expression of VCAM-1 and E-selectin, but serum from GH-treated healthy subjects significantly increased the expression of VCAM-1 (P

  20. Cell–cell signaling drives the evolution of complex traits: introduction—lung evo-devo

    Science.gov (United States)

    Torday, John S.; Rehan, V. K.

    2009-01-01

    Physiology integrates biology with the environment through cell–cell interactions at multiple levels. The evolution of the respiratory system has been “deconvoluted” (Torday and Rehan in Am J Respir Cell Mol Biol 31:8–12, 2004) through Gene Regulatory Networks (GRNs) applied to cell–cell communication for all aspects of lung biology development, homeostasis, regeneration, and aging. Using this approach, we have predicted the phenotypic consequences of failed signaling for lung development, homeostasis, and regeneration based on evolutionary principles. This cell–cell communication model predicts other aspects of vertebrate physiology as adaptational responses. For example, the oxygen-induced differentiation of alveolar myocytes into alveolar adipocytes was critical for the evolution of the lung in land dwelling animals adapting to fluctuating Phanarezoic oxygen levels over the past 500 million years. Adipocytes prevent lung injury due to oxygen radicals and facilitate the rise of endothermy. In addition, they produce the class I cytokine leptin, which augments pulmonary surfactant activity and alveolar surface area, increasing selection pressure for both respiratory oxygenation and metabolic demand initially constrained by high-systemic vascular pressure, but subsequently compensated by the evolution of the adrenomedullary beta-adrenergic receptor mechanism. Conserted positive selection for the lung and adrenals created further selection pressure for the heart, which becomes progressively more complex phylogenetically in tandem with the lung. Developmentally, increasing heart complexity and size impinges precociously on the gut mesoderm to induce the liver. That evolutionary-developmental interaction is significant because the liver provides regulated sources of glucose and glycogen to the evolving physiologic system, which is necessary for the evolution of the neocortex. Evolution of neocortical control furthers integration of physiologic systems. Such

  1. Wnt signaling positively regulates endothelial cell fate specification in the Fli1a-positive progenitor population via Lef1.

    Science.gov (United States)

    Hübner, Kathleen; Grassme, Kathrin S; Rao, Jyoti; Wenke, Nina K; Zimmer, Cordula L; Korte, Laura; Mu Ller, Katja; Sumanas, Saulius; Greber, Boris; Herzog, Wiebke

    2017-10-01

    During vertebrate embryogenesis, vascular endothelial cells (ECs) and primitive erythrocytes become specified within close proximity in the posterior lateral plate mesoderm (LPM) from a common progenitor. However, the signaling cascades regulating the specification into either lineage remain largely elusive. Here, we analyze the contribution of β-catenin dependent Wnt signaling to EC and erythrocyte specification during zebrafish embryogenesis. We generated novel β-catenin dependent Wnt signaling reporters which, by using destabilized fluorophores (Venus-Pest, dGFP), specifically allow us to detect Wnt signaling responses in narrow time windows as well as in spatially restricted domains, defined by Cre recombinase expression (Tg(axin2 BAC :Venus-Pest) mu288 ; Tg(14TCF:loxP-STOP-loxP-dGFP) mu202 ). We therefore can detect β-catenin dependent Wnt signaling activity in a subset of the Fli1a-positive progenitor population. Additionally, we show that mesodermal Wnt3a-mediated signaling via the transcription factor Lef1 positively regulates EC specification (defined by kdrl expression) at the expense of primitive erythrocyte specification (defined by gata1 expression) in zebrafish embryos. Using mesoderm derived from human embryonic stem cells, we identified the same principle of Wnt signaling dependent EC specification in conjunction with auto-upregulation of LEF1. Our data indicate a novel role of β-catenin dependent Wnt signaling in regulating EC specification during vasculogenesis. Copyright © 2017. Published by Elsevier Inc.

  2. Benfotiamine counteracts glucose toxicity effects on endothelial progenitor cell differentiation via Akt/FoxO signaling.

    Science.gov (United States)

    Marchetti, Valentina; Menghini, Rossella; Rizza, Stefano; Vivanti, Alessia; Feccia, Tiziana; Lauro, Davide; Fukamizu, Akiyoshi; Lauro, Renato; Federici, Massimo

    2006-08-01

    Dysfunction of mature endothelial cells is thought to play a major role in both micro- and macrovascular complications of diabetes. However, recent advances in biology of endothelial progenitor cells (EPCs) have highlighted their involvement in diabetes complications. To determine the effect of glucotoxicity on EPCs, human EPCs have been isolated from peripheral blood mononuclear cells of healthy donors and cultured in the presence or absence of high glucose (33 mmol/l) or high glucose plus benfotiamine to scavenge glucotoxicity. Morphological analysis revealed that high glucose significantly affected the number of endothelial cell colony forming units, uptake and binding of acLDL and Lectin-1, and the ability to differentiate into CD31- and vascular endothelial growth factor receptor 2-positive cells. Functional analysis outlined a reduced EPC involvement in de novo tube formation, when cocultured with mature endothelial cells (human umbilical vein endothelial cells) on matrigel. To explain the observed phenotypes, we have investigated the signal transduction pathways known to be involved in EPC growth and differentiation. Our results indicate that hyperglycemia impairs EPC differentiation and that the process can be restored by benfotiamine administration, via the modulation of Akt/FoxO1 activity.

  3. Arachidonic metabolism and radiation toxicity in cultures of vascular endothelial cells

    International Nuclear Information System (INIS)

    Eldor, A.; Vlodavsky, I.; Fuks, Z.; Matzner, Y.; Rubin, D.B.

    1989-01-01

    The authors conclude that the observed changes in eicosanoid production by vascular endothelial cells exposed to ionizing irradiation may be relevant to the pathogenesis of post-radiation injury in small and large blood vessels. Anomalies of PGI 2 production may lead to thrombosis and accelerated arteriosclerosis which are observed in irradiated vessels. The generation of potent cells may greatly facilitate inflammation in irradiated vessels. The model of irradiated cultured endothelial cells may also be useful for the study of various methods and agents aimed at reducing the radiation induced damage to blood vessels. Evaluation of the capacity of cultured endothelial cells to produce eicosanoids may serve as an appropriate index for the metabolic damage induced by radiation. (author)

  4. Endothelial Progenitor Cell Dysfunction in Myelodysplastic Syndromes: Possible Contribution of a Defective Vascular Niche to Myelodysplasia

    Directory of Open Access Journals (Sweden)

    Luciana Teofili

    2015-05-01

    Full Text Available We set a model to replicate the vascular bone marrow niche by using endothelial colony forming cells (ECFCs, and we used it to explore the vascular niche function in patients with low-risk myelodysplastic syndromes (MDS. Overall, we investigated 56 patients and we observed higher levels of ECFCs in MDS than in healthy controls; moreover, MDS ECFCs were found variably hypermethylated for p15INK4b DAPK1, CDH1, or SOCS1. MDS ECFCs exhibited a marked adhesive capacity to normal mononuclear cells. When normal CD34+ cells were co-cultured with MDS ECFCs, they generated significant lower amounts of CD11b+ and CD41+ cells than in co-culture with normal ECFCs. At gene expression profile, several genes involved in cell adhesion were upregulated in MDS ECFCs, while several members of the Wingless and int (Wnt pathways were underexpressed. Furthermore, at miRNA expression profile, MDS ECFCs hypo-expressed various miRNAs involved in Wnt pathway regulation. The addition of Wnt3A reduced the expression of intercellular cell adhesion molecule-1 on MDS ECFCs and restored the defective expression of markers of differentiation. Overall, our data demonstrate that in low-risk MDS, ECFCs exhibit various primary abnormalities, including putative MDS signatures, and suggest the possible contribution of the vascular niche dysfunction to myelodysplasia.

  5. Guard Cell Signal Transduction Network: Advances in Understanding Abscisic Acid, CO2, and Ca2+ Signaling

    KAUST Repository

    Kim, Tae-Houn

    2010-05-04

    Stomatal pores are formed by pairs of specialized epidermal guard cells and serve as major gateways for both CO2 influx into plants from the atmosphere and transpirational water loss of plants. Because they regulate stomatal pore apertures via integration of both endogenous hormonal stimuli and environmental signals, guard cells have been highly developed as a model system to dissect the dynamics and mechanisms of plant-cell signaling. The stress hormone ABA and elevated levels of CO2 activate complex signaling pathways in guard cells that are mediated by kinases/phosphatases, secondary messengers, and ion channel regulation. Recent research in guard cells has led to a new hypothesis for how plants achieve specificity in intracellular calcium signaling: CO2 and ABA enhance (prime) the calcium sensitivity of downstream calcium-signaling mechanisms. Recent progress in identification of early stomatal signaling components are reviewed here, including ABA receptors and CO2-binding response proteins, as well as systems approaches that advance our understanding of guard cell-signaling mechanisms.

  6. Guard Cell Signal Transduction Network: Advances in Understanding Abscisic Acid, CO2, and Ca2+ Signaling

    KAUST Repository

    Kim, Tae-Houn; Bö hmer, Maik; Hu, Honghong; Nishimura, Noriyuki; Schroeder, Julian I.

    2010-01-01

    Stomatal pores are formed by pairs of specialized epidermal guard cells and serve as major gateways for both CO2 influx into plants from the atmosphere and transpirational water loss of plants. Because they regulate stomatal pore apertures via integration of both endogenous hormonal stimuli and environmental signals, guard cells have been highly developed as a model system to dissect the dynamics and mechanisms of plant-cell signaling. The stress hormone ABA and elevated levels of CO2 activate complex signaling pathways in guard cells that are mediated by kinases/phosphatases, secondary messengers, and ion channel regulation. Recent research in guard cells has led to a new hypothesis for how plants achieve specificity in intracellular calcium signaling: CO2 and ABA enhance (prime) the calcium sensitivity of downstream calcium-signaling mechanisms. Recent progress in identification of early stomatal signaling components are reviewed here, including ABA receptors and CO2-binding response proteins, as well as systems approaches that advance our understanding of guard cell-signaling mechanisms.

  7. Changes in adipose tissue stromal-vascular cells in primary culture due to porcine sera

    International Nuclear Information System (INIS)

    Jewell, D.E.; Hausman, G.J.

    1986-01-01

    This study was conducted to determine the response of rat stromal-vascular cells to pig sea. Sera were collected from unselected contemporary (lean) and high backfat thickness selected (obese) pigs. Sera from obese pigs were collected either by exsanguination or cannulation. sera from lean pigs during the growing phase (45 kg) and the fattening phase (100-110 kg) were collected. Stromal-vascular cells derived rom rat inguinal tissue were cultured on either 25 cm 2 flasks, collagen-coated coverslips or petri dishes. Cell proliferation was measured by [ 3 H]-thymidine incorporation during the fourth day of culture. Coverslip cultures were used for histochemical analysis. Petri dish cultures were used for analysis of Sn-glycerol-3-phosphate dehydrogenase (GPDH) activity. All cells were plated for 24 hours in media containing 10 fetal bovine sera. Test media contained 2.5, 5.0, 10.0% sera. Sera from obese pigs increased GPDH activity and fat cell production when compared to the lean controls. The increased concentration of sera increased esterase activity and lipid as measured with oil red O. The sera from obese pigs collected at slaughter stimulated more fat cell production than obese sera collected by cannulation. These studies show there are adipogenic factors in obese pigs sera which promote fat cell development in primary cell culture

  8. Inhibition of tumor angiogenesis and tumor growth by the DSL domain of human Delta-like 1 targeted to vascular endothelial cells.

    Science.gov (United States)

    Zhao, Xing-Cheng; Dou, Guo-Rui; Wang, Li; Liang, Liang; Tian, Deng-Mei; Cao, Xiu-Li; Qin, Hong-Yan; Wang, Chun-Mei; Zhang, Ping; Han, Hua

    2013-07-01

    The growth of solid tumors depends on neovascularization. Several therapies targeting tumor angiogenesis have been developed. However, poor response in some tumors and emerging resistance necessitate further investigations of new drug targets. Notch signal pathway plays a pivotal role in vascular development and tumor angiogenesis. Either blockade or forced activation of this pathway can inhibit angiogenesis. As blocking Notch pathway results in the formation of vascular neoplasm, activation of Notch pathway to prevent tumor angiogenesis might be an alternative choice. However, an in vivo deliverable reagent with highly efficient Notch-activating capacity has not been developed. Here, we generated a polypeptide, hD1R, which consists of the Delta-Serrate-Lag-2 fragment of the human Notch ligand Delta-like 1 and an arginine-glycine-aspartate (RGD) motif targeting endothelial cells (ECs). We showed that hD1R could bind to ECs specifically through its RGD motif and effectively triggered Notch signaling in ECs. We demonstrated both in vitro and in vivo that hD1R inhibited angiogenic sprouting and EC proliferation. In tumor-bearing mice, the injection of hD1R effectively repressed tumor growth, most likely through increasing tumor hypoxia and tissue necrosis. The amount and width of vessels reduced remarkably in tumors of mice treated with hD1R. Moreover, vessels in tumors of mice treated with hD1R recruited more NG2(+) perivascular cells and were better perfused. Combined application of hD1R and chemotherapy with cisplatin and teniposide revealed that these two treatments had additive antitumor effects. Our study provided a new strategy for antiangiogenic tumor therapy.

  9. Inhibition of Tumor Angiogenesis and Tumor Growth by the DSL Domain of Human Delta-Like 1 Targeted to Vascular Endothelial Cells

    Directory of Open Access Journals (Sweden)

    Xing-Cheng Zhao

    2013-07-01

    Full Text Available The growth of solid tumors depends on neovascularization. Several therapies targeting tumor angiogenesis have been developed. However, poor response in some tumors and emerging resistance necessitate further investigations of newdrug targets. Notch signal pathway plays a pivotal role in vascular development and tumor angiogenesis. Either blockade or forced activation of this pathway can inhibit angiogenesis. As blocking Notch pathway results in the formation of vascular neoplasm, activation of Notch pathway to prevent tumor angiogenesis might be an alternative choice. However, an in vivo deliverable reagent with highly efficient Notch-activating capacity has not been developed. Here, we generated a polypeptide, hD1R, which consists of the Delta-Serrate-Lag-2 fragment of the human Notch ligand Delta-like 1 and an arginine-glycine-aspartate (RGD motif targeting endothelial cells (ECs. We showed that hD1R could bind to ECs specifically through its RGD motif and effectively triggered Notch signaling in ECs. We demonstrated both in vitro and in vivo that hD1R inhibited angiogenic sprouting and EC proliferation. In tumor-bearing mice, the injection of hD1R effectively repressed tumor growth, most likely through increasing tumor hypoxia and tissue necrosis. The amount and width of vessels reduced remarkably in tumors of mice treated with hD1R. Moreover, vessels in tumors of mice treated with hD1R recruited more NG2+ perivascular cells and were better perfused. Combined application of hD1R and chemotherapy with cisplatin and teniposide revealed that these two treatments had additive antitumor effects. Our study provided a new strategy for antiangiogenic tumor therapy.

  10. Epigenetic regulation of vascular smooth muscle cell proliferation and neointima formation by histone deacetylase inhibition.

    Science.gov (United States)

    Findeisen, Hannes M; Gizard, Florence; Zhao, Yue; Qing, Hua; Heywood, Elizabeth B; Jones, Karrie L; Cohn, Dianne; Bruemmer, Dennis

    2011-04-01

    Proliferation of smooth muscle cells (SMC) in response to vascular injury is central to neointimal vascular remodeling. There is accumulating evidence that histone acetylation constitutes a major epigenetic modification for the transcriptional control of proliferative gene expression; however, the physiological role of histone acetylation for proliferative vascular disease remains elusive. In the present study, we investigated the role of histone deacetylase (HDAC) inhibition in SMC proliferation and neointimal remodeling. We demonstrate that mitogens induce transcription of HDAC 1, 2, and 3 in SMC. Short interfering RNA-mediated knockdown of either HDAC 1, 2, or 3 and pharmacological inhibition of HDAC prevented mitogen-induced SMC proliferation. The mechanisms underlying this reduction of SMC proliferation by HDAC inhibition involve a growth arrest in the G(1) phase of the cell cycle that is due to an inhibition of retinoblastoma protein phosphorylation. HDAC inhibition resulted in a transcriptional and posttranscriptional regulation of the cyclin-dependent kinase inhibitors p21(Cip1) and p27(Kip). Furthermore, HDAC inhibition repressed mitogen-induced cyclin D1 mRNA expression and cyclin D1 promoter activity. As a result of this differential cell cycle-regulatory gene expression by HDAC inhibition, the retinoblastoma protein retains a transcriptional repression of its downstream target genes required for S phase entry. Finally, we provide evidence that these observations are applicable in vivo by demonstrating that HDAC inhibition decreased neointima formation and expression of cyclin D1 in a murine model of vascular injury. These findings identify HDAC as a critical component of a transcriptional cascade regulating SMC proliferation and suggest that HDAC might play a pivotal role in the development of proliferative vascular diseases, including atherosclerosis and in-stent restenosis.

  11. Progranulin protects vascular endothelium against atherosclerotic inflammatory reaction via Akt/eNOS and nuclear factor-κB pathways.

    Directory of Open Access Journals (Sweden)

    Hwan-Jin Hwang

    Full Text Available OBJECTIVE: Atherosclerosis is considered a chronic inflammatory disease, initiated by activation and dysfunction of the endothelium. Recently, progranulin has been regarded as an important modulator of inflammatory processes; however, the role for prgranulin in regulating inflammation in vascular endothelial cells has not been described. METHOD AND RESULTS: Signaling pathways mediated by progranulin were analyzed in human umbilical vein endothelial cells (HUVECs treated with progranulin. Progranulin significantly induced Akt and endothelial nitric oxide synthase (eNOS phosphorylation in HUVECs, an effect that was blocked with Akt inhibitor. Furthermore, nitric oxide (NO level, the end product of Akt/eNOS pathway, was significantly upregulated after progranulin treatment. Next, we showed that progranulin efficiently inhibited lipopolysaccharide (LPS-mediated pro-inflammatory signaling. LPS-induced phosphorylation of IκB and nuclear factor-κB (NF-κB levels decreased after progranulin treatment. Also, progranulin blocked translocation of NF-κB from the cytosol to the nucleus. In addition, progranulin significantly reduced the expression of vascular cell adhesion molecule-1 (VCAM-1 and intercellular adhesion molecule-1 (ICAM-1 by inhibiting binding of NF- κB to their promoter regions and blocked attachment of monocytes to HUVECs. Progranulin also significantly reduced the expression of tumor necrosis factor receptor-α (TNF-α and monocyte chemo-attractant protein-1 (MCP-1, the crucial inflammatory molecules known to aggravate atherosclerosis. CONCLUSION: Progranulin efficiently inhibited LPS-mediated pro-inflammatory signaling in endothelial cells through activation of the Akt/eNOS pathway and attenuation of the NF-κB pathway, suggesting its protective roles in vascular endothelium against inflammatory reaction underlying atherosclerosis.

  12. Fibroblast growth factor regulates insulin-like growth factor-binding protein production by vascular smooth muscle cells.

    Science.gov (United States)

    Ververis, J; Ku, L; Delafontaine, P

    1994-02-01

    Insulin-like growth factor I is an important mitogen for vascular smooth muscle cells, and its effects are regulated by several binding proteins. Western ligand blotting of conditioned medium from rat aortic smooth muscle cells detected a 24 kDa binding protein and a 28 kDa glycosylated variant of this protein, consistent with insulin-like growth factor binding protein-4 by size. Low amounts of a glycosylated 38 to 42 kDa doublet (consistent with binding protein-3) and a 31 kDa non-glycosylated protein also were present. Basic fibroblast growth factor markedly increased secretion of the 24 kDa binding protein and its 28 kDa glycosylated variant. This effect was dose- and time-dependent and was inhibited by co-incubation with cycloheximide. Crosslinking of [125I]-insulin-like growth factor I to cell monolayers revealed no surface-associated binding proteins, either basally or after agonist treatment. Induction of binding protein production by fibroblast growth factor at sites of vascular injury may be important in vascular proliferative responses in vivo.

  13. Arsenite enhances tumor necrosis factor-α-induced expression of vascular cell adhesion molecule-1

    International Nuclear Information System (INIS)

    Tsou, T.-C.; Yeh, Szu Ching; Tsai, E.-M.; Tsai, F.-Y.; Chao, H.-R.; Chang, Louis W.

    2005-01-01

    Epidemiological studies demonstrated a high association of vascular diseases with arsenite exposure. We hypothesize that arsenite potentiates the effect of proinflammatory cytokines on vascular endothelial cells, and hence contributes to atherosclerosis. In this study, we investigated the effect of arsenite and its induction of glutathione (GSH) on vascular cell adhesion molecule-1 (VCAM-1) protein expression in human umbilical vein endothelial cells (HUVECs) in response to tumor necrosis factor-α (TNF-α), a typical proinflammatory cytokine. Our study demonstrated that arsenite pretreatment potentiated the TNF-α-induced VCAM-1 expression with up-regulations of both activator protein-1 (AP-1) and nuclear factor-κB (NF-κB). To elucidate the role of GSH in regulation of AP-1, NF-κB, and VCAM-1 expression, we employed L-buthionine (S,R)-sulfoximine (BSO), a specific γ-glutamylcysteine synthetase (γ-GCS) inhibitor, to block intracellular GSH synthesis. Our investigation revealed that, by depleting GSH, arsenite attenuated the TNF-α-induced VCAM-1 expression as well as a potentiation of AP-1 and an attenuation of NF-κB activations by TNF-α. Moreover, we found that depletion of GSH would also attenuate the TNF-α-induced VCAM-1 expression with a down-regulation of the TNF-α-induced NF-κB activation and without significant effect on AP-1. On the other hand, the TNF-α-induced VCAM-1 expression could be completely abolished by inhibition of AP-1 or NF-κB activity, suggesting that activation of both AP-1 and NF-κB was necessary for VCAM-1 expression. In summary, we demonstrate that arsenite enhances the TNF-α-induced VCAM-1 expression in HUVECs via regulation of AP-1 and NF-κB activities in a GSH-sensitive manner. Our present study suggested a potential mechanism for arsenite in the induction of vascular inflammation and vascular diseases via modulating the actions of proinflammatory cytokines

  14. Modulating the vascular behavior of metastatic breast cancer cells by curcumin treatment

    Energy Technology Data Exchange (ETDEWEB)

    Palange, Anna L. [Department of Translational Imaging, The Methodist Hospital Research Institute, Houston, TX (United States); Department of Nanomedicine, The Methodist Hospital Research Institute, Houston, TX (United States); Mascolo, Daniele Di [Department of Translational Imaging, The Methodist Hospital Research Institute, Houston, TX (United States); Department of Nanomedicine, The Methodist Hospital Research Institute, Houston, TX (United States); Department of Experimental and Clinical Medicine, University of Magna Graecia, Catanzaro (Italy); Singh, Jaykrishna [Department of Translational Imaging, The Methodist Hospital Research Institute, Houston, TX (United States); Department of Nanomedicine, The Methodist Hospital Research Institute, Houston, TX (United States); Franceschi, Maria S. De; Carallo, Claudio; Gnasso, Agostino [Department of Translational Imaging, The Methodist Hospital Research Institute, Houston, TX (United States); Decuzzi, Paolo, E-mail: pdecuzzi@tmhs.org [Department of Translational Imaging, The Methodist Hospital Research Institute, Houston, TX (United States); Department of Nanomedicine, The Methodist Hospital Research Institute, Houston, TX (United States); Department of Experimental and Clinical Medicine, University of Magna Graecia, Catanzaro (Italy)

    2012-11-15

    The spreading of tumor cells to secondary sites (tumor metastasis) is a complex process that involves multiple, sequential steps. Vascular adhesion and extravasation of circulating tumor cells (CTCs) is one, critical step. Curcumin, a natural compound extracted from Curcuma longa, is known to have anti-tumoral, anti-proliferative, anti-inflammatory properties and affect the expression of cell adhesion molecules, mostly by targeting the NF-κB transcription factor. Here, upon treatment with curcumin, the vascular behavior of three different estrogen receptor negative (ER{sup –}) breast adenocarcinoma cell lines (SK-BR-3, MDA-MB-231, MDA-MB-468) is analyzed using a microfluidic system. First, the dose response to curcumin is characterized at 24, 48, and 72 h using a XTT assay. For all three cell lines, an IC{sub 50} larger than 20 µM is observed at 72 h; whereas no significant reduction in cell viability is detected for curcumin concentrations up to 10 µM. Upon 24 h treatment at 10 µM of curcumin, SK-BR3 and MDA-MB-231 cells show a decrease in adhesion propensity of 40% (p = 0.02) and 47% (p = 0.001), respectively. No significant change is documented for the less metastatic MDA-MB-468 cells. All three treated cell lines show a 20% increase in rolling velocity from 48.3 to 58.7 µm/s in SK-BR-3, from 64.1 to 73.77 µm/s in MDA-MB-231, and from 57.5 to 74.4 µm/s in MDA-MB-468. Collectively, these results suggest that mild curcumin treatments could limit the metastatic potential of these adenocarcinoma cell lines, possibly by altering the expression of adhesion molecules, and the organization and stiffness of the cell cytoskeleton. Future studies will elucidate the biophysical mechanisms regulating this curcumin-induced behavior and further explore the clinical relevance of these findings.

  15. Modulating the vascular behavior of metastatic breast cancer cells by curcumin treatment

    International Nuclear Information System (INIS)

    Palange, Anna L.; Mascolo, Daniele Di; Singh, Jaykrishna; Franceschi, Maria S. De; Carallo, Claudio; Gnasso, Agostino; Decuzzi, Paolo

    2012-01-01

    The spreading of tumor cells to secondary sites (tumor metastasis) is a complex process that involves multiple, sequential steps. Vascular adhesion and extravasation of circulating tumor cells (CTCs) is one, critical step. Curcumin, a natural compound extracted from Curcuma longa, is known to have anti-tumoral, anti-proliferative, anti-inflammatory properties and affect the expression of cell adhesion molecules, mostly by targeting the NF-κB transcription factor. Here, upon treatment with curcumin, the vascular behavior of three different estrogen receptor negative (ER – ) breast adenocarcinoma cell lines (SK-BR-3, MDA-MB-231, MDA-MB-468) is analyzed using a microfluidic system. First, the dose response to curcumin is characterized at 24, 48, and 72 h using a XTT assay. For all three cell lines, an IC 50 larger than 20 µM is observed at 72 h; whereas no significant reduction in cell viability is detected for curcumin concentrations up to 10 µM. Upon 24 h treatment at 10 µM of curcumin, SK-BR3 and MDA-MB-231 cells show a decrease in adhesion propensity of 40% (p = 0.02) and 47% (p = 0.001), respectively. No significant change is documented for the less metastatic MDA-MB-468 cells. All three treated cell lines show a 20% increase in rolling velocity from 48.3 to 58.7 µm/s in SK-BR-3, from 64.1 to 73.77 µm/s in MDA-MB-231, and from 57.5 to 74.4 µm/s in MDA-MB-468. Collectively, these results suggest that mild curcumin treatments could limit the metastatic potential of these adenocarcinoma cell lines, possibly by altering the expression of adhesion molecules, and the organization and stiffness of the cell cytoskeleton. Future studies will elucidate the biophysical mechanisms regulating this curcumin-induced behavior and further explore the clinical relevance of these findings.

  16. Modulating the vascular behavior of metastatic breast cancer cells by curcumin treatment

    Directory of Open Access Journals (Sweden)

    Anna Lisa ePalange

    2012-11-01

    Full Text Available The spreading of tumor cells to secondary sites (tumor metastasis is a complex process that involves multiple, sequential steps. Vascular adhesion and extravasation of circulating tumor cells (CTCs is one, critical step. Curcumin, a natural compound extracted from Curcuma longa, is known to have anti-tumoral, anti-proliferative, anti-inflammatory properties and affect the expression of cell adhesion molecules, mostly by targeting the NF-κB transcription factor. Here, upon treatment with Curcumin, the vascular behavior of three different estrogen receptor negative (ER– breast adenocarcinoma cell lines (SK-BR-3, MDA-MB-231, MDA-MB-468 is analyzed using a microfluidic system. First, the dose response to curcumin is characterized at 24, 48 and 72h using a XTT assay. For all three cell lines, an IC50 larger than 20 µM is observed at 72 h; whereas no significant reduction in cell viability is detected for curcumin concentrations up to 10 µM. Upon 24 h treatment at 10 µM of curcumin, SK-BR3 and MDA-MB-231 cells show a decrease in adhesion propensity of 40% (p = 0.02 and 47% (p = 0.001, respectively. No significant change is documented for the less metastatic MDA-MB-468 cells. All three treated cell lines show a 20% increase in rolling velocity from 48.3 to 58.7 µm/s in SK-BR-3, from 64.1 to 73.77 µm/s in MDA-MB-231 and from 57.5 to 74.4 µm/s in MDA-MB-468. Collectively, these results suggest that mild curcumin treatments could limit the metastatic potential of these adenocarcinoma cell lines, possibly by altering the expression of adhesion molecules, and the organization and stiffness of the cell cytoskeleton. Future studies will elucidate the biophysical mechanisms regulating this curcumin-induced behavior and further explore the clinical relevance of these findings.

  17. Chansporter complexes in cell signaling.

    Science.gov (United States)

    Abbott, Geoffrey W

    2017-09-01

    Ion channels facilitate diffusion of ions across cell membranes for such diverse purposes as neuronal signaling, muscular contraction, and fluid homeostasis. Solute transporters often utilize ionic gradients to move aqueous solutes up their concentration gradient, also fulfilling a wide variety of tasks. Recently, an increasing number of ion channel-transporter ('chansporter') complexes have been discovered. Chansporter complex formation may overcome what could otherwise be considerable spatial barriers to rapid signal integration and feedback between channels and transporters, the ions and other substrates they transport, and environmental factors to which they must respond. Here, current knowledge in this field is summarized, covering both heterologous expression structure/function findings and potential mechanisms by which chansporter complexes fulfill contrasting roles in cell signaling in vivo. © 2017 Federation of European Biochemical Societies.

  18. Wnt Signalling in Gastrointestinal Epithelial Stem Cells

    Directory of Open Access Journals (Sweden)

    Dustin J. Flanagan

    2018-03-01

    Full Text Available Wnt signalling regulates several cellular functions including proliferation, differentiation, apoptosis and migration, and is critical for embryonic development. Stem cells are defined by their ability for self-renewal and the ability to be able to give rise to differentiated progeny. Consequently, they are essential for the homeostasis of many organs including the gastrointestinal tract. This review will describe the huge advances in our understanding of how stem cell functions in the gastrointestinal tract are regulated by Wnt signalling, including how deregulated Wnt signalling can hijack these functions to transform cells and lead to cancer.

  19. Regulation of Cell Wall Biogenesis in Saccharomyces cerevisiae: The Cell Wall Integrity Signaling Pathway

    Science.gov (United States)

    Levin, David E.

    2011-01-01

    The yeast cell wall is a strong, but elastic, structure that is essential not only for the maintenance of cell shape and integrity, but also for progression through the cell cycle. During growth and morphogenesis, and in response to environmental challenges, the cell wall is remodeled in a highly regulated and polarized manner, a process that is principally under the control of the cell wall integrity (CWI) signaling pathway. This pathway transmits wall stress signals from the cell surface to the Rho1 GTPase, which mobilizes a physiologic response through a variety of effectors. Activation of CWI signaling regulates the production of various carbohydrate polymers of the cell wall, as well as their polarized delivery to the site of cell wall remodeling. This review article centers on CWI signaling in Saccharomyces cerevisiae through the cell cycle and in response to cell wall stress. The interface of this signaling pathway with other pathways that contribute to the maintenance of cell wall integrity is also discussed. PMID:22174182

  20. Role of Galectin-3 in Bone Cell Differentiation, Bone Pathophysiology and Vascular Osteogenesis

    Directory of Open Access Journals (Sweden)

    Carla Iacobini

    2017-11-01

    Full Text Available Galectin-3 is expressed in various tissues, including the bone, where it is considered a marker of chondrogenic and osteogenic cell lineages. Galectin-3 protein was found to be increased in the differentiated chondrocytes of the metaphyseal plate cartilage, where it favors chondrocyte survival and cartilage matrix mineralization. It was also shown to be highly expressed in differentiating osteoblasts and osteoclasts, in concomitance with expression of osteogenic markers and Runt-related transcription factor 2 and with the appearance of a mature phenotype. Galectin-3 is expressed also by osteocytes, though its function in these cells has not been fully elucidated. The effects of galectin-3 on bone cells were also investigated in galectin-3 null mice, further supporting its role in all stages of bone biology, from development to remodeling. Galectin-3 was also shown to act as a receptor for advanced glycation endproducts, which have been implicated in age-dependent and diabetes-associated bone fragility. Moreover, its regulatory role in inflammatory bone and joint disorders entitles galectin-3 as a possible therapeutic target. Finally, galectin-3 capacity to commit mesenchymal stem cells to the osteoblastic lineage and to favor transdifferentiation of vascular smooth muscle cells into an osteoblast-like phenotype open a new area of interest in bone and vascular pathologies.

  1. Neuropilin-2 mediated β-catenin signaling and survival in human gastro-intestinal cancer cell lines.

    Directory of Open Access Journals (Sweden)

    Shaija Samuel

    Full Text Available NRP-2 is a high-affinity kinase-deficient receptor for ligands belonging to the class 3 semaphorin and vascular endothelial growth factor families. NRP-2 has been detected on the surface of several types of human cancer cells, but its expression and function in gastrointestinal (GI cancer cells remains to be determined. We sought to determine the function of NRP-2 in mediating downstream signals regulating the growth and survival of human gastrointestinal cancer cells. In human gastric cancer specimens, NRP-2 expression was detected in tumor tissues but not in adjacent normal mucosa. In CNDT 2.5 cells, shRNA mediated knockdown NRP-2 expression led to decreased migration and invasion in vitro (p<0.01. Focused gene-array analysis demonstrated that loss of NRP-2 reduced the expression of a critical metastasis mediator gene, S100A4. Steady-state levels and function of β-catenin, a known regulator of S100A4, were also decreased in the shNRP-2 clones. Furthermore, knockdown of NRP-2 sensitized CNDT 2.5 cells in vitro to 5FU toxicity. This effect was associated with activation of caspases 3 and 7, cleavage of PARP, and downregulation of Bcl-2. In vivo growth of CNDT 2.5 cells in the livers of nude mice was significantly decreased in the shNRP-2 group (p<0.05. Intraperitoneal administration of NRP-2 siRNA-DOPC decreased the tumor burden in mice (p = 0.01. Collectively, our results demonstrate that tumor cell-derived NRP-2 mediates critical survival signaling in gastrointestinal cancer cells.

  2. Artemisinic acid exhibits antitumor activity in MCF-7 breast cancer cells through the inhibition of angiogenesis, VEGF, m-TOR and AKT signalling pathways

    Directory of Open Access Journals (Sweden)

    Yan Cui

    2016-09-01

    Full Text Available The aim of the present study was to evaluate the antitumor and anti-angiogenic effects of artemisinic acid in MCF-7 human breast cancer cells. Various cell signalling pathways (VEGF, m-TOR and AKT signalling pathways and MTT assay were used. The in vivo antitumor activity of artemisinic acid was evaluated by means of tumor xenograft mouse model. Transwell cell migration assay was used to examine the chemotactic motility of the human umbilical vascular endothelial cells (HUVECs, while as endothelial cell capillary-like tube formation assay was used to evaluate the effect of artemisinic acid on the tube formation in HUVECs. We found that artemisinic acid considerably reduced both the volume and weight of concrete tumors and reduced angiogenesis in a xenograft mouse tumor model in vivo. Further, artemisinic acid suppressed the VEGF-induced cell migration and capillary-like tube formation of HUVECs in a dose-dependent manner. Artemisinic acid was found to suppress the VEGF-induced phosphorylation of VEGFR2 and also the activity of AKT and m-TOR.

  3. Vascular smooth muscle cell phenotypic changes in patients with Marfan syndrome.

    Science.gov (United States)

    Crosas-Molist, Eva; Meirelles, Thayna; López-Luque, Judit; Serra-Peinado, Carla; Selva, Javier; Caja, Laia; Gorbenko Del Blanco, Darya; Uriarte, Juan José; Bertran, Esther; Mendizábal, Yolanda; Hernández, Vanessa; García-Calero, Carolina; Busnadiego, Oscar; Condom, Enric; Toral, David; Castellà, Manel; Forteza, Alberto; Navajas, Daniel; Sarri, Elisabet; Rodríguez-Pascual, Fernando; Dietz, Harry C; Fabregat, Isabel; Egea, Gustavo

    2015-04-01

    Marfan's syndrome is characterized by the formation of ascending aortic aneurysms resulting from altered assembly of extracellular matrix microfibrils and chronic tissue growth factor (TGF)-β signaling. TGF-β is a potent regulator of the vascular smooth muscle cell (VSMC) phenotype. We hypothesized that as a result of the chronic TGF-β signaling, VSMC would alter their basal differentiation phenotype, which could facilitate the formation of aneurysms. This study explores whether Marfan's syndrome entails phenotypic alterations of VSMC and possible mechanisms at the subcellular level. Immunohistochemical and Western blotting analyses of dilated aortas from Marfan patients showed overexpression of contractile protein markers (α-smooth muscle actin, smoothelin, smooth muscle protein 22 alpha, and calponin-1) and collagen I in comparison with healthy aortas. VSMC explanted from Marfan aortic aneurysms showed increased in vitro expression of these phenotypic markers and also of myocardin, a transcription factor essential for VSMC-specific differentiation. These alterations were generally reduced after pharmacological inhibition of the TGF-β pathway. Marfan VSMC in culture showed more robust actin stress fibers and enhanced RhoA-GTP levels, which was accompanied by increased focal adhesion components and higher nuclear localization of myosin-related transcription factor A. Marfan VSMC and extracellular matrix measured by atomic force microscopy were both stiffer than their respective controls. In Marfan VSMC, both in tissue and in culture, there are variable TGF-β-dependent phenotypic changes affecting contractile proteins and collagen I, leading to greater cellular and extracellular matrix stiffness. Altogether, these alterations may contribute to the known aortic rigidity that precedes or accompanies Marfan's syndrome aneurysm formation. © 2015 American Heart Association, Inc.

  4. Vascular remodeling: A redox-modulated mechanism of vessel caliber regulation.

    Science.gov (United States)

    Tanaka, Leonardo Y; Laurindo, Francisco R M

    2017-08-01

    Vascular remodeling, i.e. whole-vessel structural reshaping, determines lumen caliber in (patho)physiology. Here we review mechanisms underlying vessel remodeling, with emphasis in redox regulation. First, we discuss confusing terminology and focus on strictu sensu remodeling. Second, we propose a mechanobiological remodeling paradigm based on the concept of tensional homeostasis as a setpoint regulator. We first focus on shear-mediated models as prototypes of remodeling closely dominated by highly redox-sensitive endothelial function. More detailed discussions focus on mechanosensors, integrins, extracellular matrix, cytoskeleton and inflammatory pathways as potential of mechanisms potentially coupling tensional homeostasis to redox regulation. Further discussion of remodeling associated with atherosclerosis and injury repair highlights important aspects of redox vascular responses. While neointima formation has not shown consistent responsiveness to antioxidants, vessel remodeling has been more clearly responsive, indicating that despite the multilevel redox signaling pathways, there is a coordinated response of the whole vessel. Among mechanisms that may orchestrate redox pathways, we discuss roles of superoxide dismutase activity and extracellular protein disulfide isomerase. We then discuss redox modulation of aneurysms, a special case of expansive remodeling. We propose that the redox modulation of vascular remodeling may reflect (1) remodeling pathophysiology is dominated by a particularly redox-sensitive cell type, e.g., endothelial cells (2) redox pathways are temporospatially coordinated at an organ level across distinct cellular and acellular structures or (3) the tensional homeostasis setpoint is closely connected to redox signaling. The mechanobiological/redox model discussed here can be a basis for improved understanding of remodeling and helps clarifying mechanisms underlying prevalent hard-to-treat diseases. Copyright © 2017 Elsevier Inc. All

  5. Ageing induced vascular smooth muscle cell senescence in atherosclerosis.

    Science.gov (United States)

    Uryga, Anna K; Bennett, Martin R

    2016-04-15

    Atherosclerosis is a disease of ageing in that its incidence and prevalence increase with age. However, atherosclerosis is also associated with biological ageing, manifest by a number of typical hallmarks of ageing in the atherosclerotic plaque. Thus, accelerated biological ageing may be superimposed on the effects of chronological ageing in atherosclerosis. Tissue ageing is seen in all cells that comprise the plaque, but particularly in vascular smooth muscle cells (VSMCs). Hallmarks of ageing include evidence of cell senescence, DNA damage (including telomere attrition), mitochondrial dysfunction, a pro-inflammatory secretory phenotype, defects in proteostasis, epigenetic changes, deregulated nutrient sensing, and exhaustion of progenitor cells. In this model, initial damage to DNA (genomic, telomeric, mitochondrial and epigenetic changes) results in a number of cellular responses (cellular senescence, deregulated nutrient sensing and defects in proteostasis). Ultimately, ongoing damage and attempts at repair by continued proliferation overwhelm reparative capacity, causing loss of specialised cell functions, cell death and inflammation. This review summarises the evidence for accelerated biological ageing in atherosclerosis, the functional consequences of cell ageing on cells comprising the plaque, and the causal role that VSMC senescence plays in atherogenesis. © 2015 The Authors. The Journal of Physiology © 2015 The Physiological Society.

  6. Reconstruction and signal propagation analysis of the Syk signaling network in breast cancer cells.

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    Aurélien Naldi

    2017-03-01

    Full Text Available The ability to build in-depth cell signaling networks from vast experimental data is a key objective of computational biology. The spleen tyrosine kinase (Syk protein, a well-characterized key player in immune cell signaling, was surprisingly first shown by our group to exhibit an onco-suppressive function in mammary epithelial cells and corroborated by many other studies, but the molecular mechanisms of this function remain largely unsolved. Based on existing proteomic data, we report here the generation of an interaction-based network of signaling pathways controlled by Syk in breast cancer cells. Pathway enrichment of the Syk targets previously identified by quantitative phospho-proteomics indicated that Syk is engaged in cell adhesion, motility, growth and death. Using the components and interactions of these pathways, we bootstrapped the reconstruction of a comprehensive network covering Syk signaling in breast cancer cells. To generate in silico hypotheses on Syk signaling propagation, we developed a method allowing to rank paths between Syk and its targets. We first annotated the network according to experimental datasets. We then combined shortest path computation with random walk processes to estimate the importance of individual interactions and selected biologically relevant pathways in the network. Molecular and cell biology experiments allowed to distinguish candidate mechanisms that underlie the impact of Syk on the regulation of cortactin and ezrin, both involved in actin-mediated cell adhesion and motility. The Syk network was further completed with the results of our biological validation experiments. The resulting Syk signaling sub-networks can be explored via an online visualization platform.

  7. Activated factor X signaling via protease-activated receptor 2 suppresses pro-inflammatory cytokine production from LPS-stimulated myeloid cells.

    LENUS (Irish Health Repository)

    Gleeson, Eimear M

    2013-07-19

    Vitamin K-dependent proteases generated in response to vascular injury and infection enable fibrin clot formation, but also trigger distinct immuno-regulatory signaling pathways on myeloid cells. Factor Xa, a protease crucial for blood coagulation, also induces protease-activated receptor-dependent cell signaling. Factor Xa can bind both monocytes and macrophages, but whether factor Xa-dependent signaling stimulates or suppresses myeloid cell cytokine production in response to Toll-like receptor activation is not known. In this study, exposure to factor Xa significantly impaired pro-inflammatory cytokine production from lipopolysaccharide-treated peripheral blood mononuclear cells, THP-1 monocytic cells and murine macrophages. Furthermore, factor Xa inhibited nuclear factor-kappa B activation in THP-1 reporter cells, requiring phosphatidylinositide 3-kinase activity for its anti-inflammatory effect. Active-site blockade, γ-carboxyglutamic acid domain truncation and a peptide mimic of the factor Xa inter-epidermal growth factor-like region prevented factor Xa inhibition of lipopolysaccharide-induced tumour necrosis factor-α release. In addition, factor Xa anti-inflammatory activity was markedly attenuated by the presence of an antagonist of protease-activated receptor 2, but not protease-activated receptor 1. The key role of protease-activated receptor 2 in eliciting factor Xa-dependent anti-inflammatory signaling on macrophages was further underscored by the inability of factor Xa to mediate inhibition of tumour necrosis factor-α and interleukin-6 release from murine bone marrow-derived protease-activated receptor 2-deficient macrophages. We also show for the first time that, in addition to protease-activated receptor 2, factor Xa requires a receptor-associated protein-sensitive low-density lipoprotein receptor to inhibit lipopolysaccharide-induced cytokine production. Collectively, this study supports a novel function for factor Xa as an endogenous, receptor

  8. CCN5 modulates the antiproliferative effect of heparin and regulates cell motility in vascular smooth muscle cells

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    Castellot John J

    2003-11-01

    Full Text Available Abstract Background Vascular smooth muscle cell (VSMC hyperplasia plays an important role in both chronic and acute vascular pathologies including atherosclerosis and restenosis. Considerable work has focused on the mechanisms regulating VSMC proliferation and motility. Earlier work in our lab revealed a novel growth arrest-specific (gas gene induced in VSMC exposed to the antiproliferative agent heparin. This gene is a member of the CCN family and has been given the name CCN5. The objective of the present study is to elucidate the function of CCN5 protein and to explore its mechanism of action in VSMC. Results Using RNA interference (RNAi, we first demonstrate that CCN5 is required for the antiproliferative effect of heparin in VSMC. We also use this gene knockdown approach to show that CCN5 is an important negative regulator of motility. To explore the mechanism of action of CCN5 on VSMC motility, we use RNAi to demonstrate that knock down of CCN5 up regulates expression of matrix metalloproteinase-2 (MMP-2, an important stimulator of motility in VSMC. In addition, forced expression of CCN5 via adenovirus results in reduced MMP-2 activity, this also corroborates the gene knock down results. Finally, we show that loss of CCN5 expression in VSMC causes changes in VSMC morphology and cytoskeletal organization, including a reduction in the amount and macromolecular assembly of smooth muscle cell α-actin. Conclusions This work provides important new insights into the regulation of smooth muscle cell proliferation and motility by CCN5 and may aid the development of therapies for vascular diseases.

  9. Cell signaling during Trypanosoma cruzi invasion

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    Fernando Yukio Maeda

    2012-11-01

    Full Text Available Cell signaling is an essential requirement for mammalian cell invasion by Trypanosoma cruzi. Depending on the parasite strain and the parasite developmental form, distinct signaling pathways may be induced. In this short review, we focus on the data coming from studies with metacyclic trypomastigotes (MT generated in vitro and tissue culture-derived trypomastigotes (TCT, used as counterparts of insect-borne and bloodstream parasites respectively. During invasion of host cells by MT or TCT, intracellular Ca2+ mobilization and host cell lysosomal exocytosis are triggered. Invasion mediated by MT surface molecule gp82 requires the activation of mammalian target of rapamycin (mTOR, phosphatidylinositol 3-kinase (PI3K and protein kinase C (PKC in the host cell, associated with Ca2+-dependent disruption of the actin cytoskeleton. In MT, protein tyrosine kinase (PTK, PI3K, phospholipase C (PLC and PKC appear to be activated. TCT invasion, on the other hand, does not rely on mTOR activation, rather on target cell PI3K, and may involve the host cell autophagy for parasite internalization. Enzymes, such oligopeptidase B and the major T. cruzi cysteine proteinase cruzipain, have been shown to generate molecules that induce target cell Ca2+ signal. In addition, TCT may trigger host cell responses mediated by TGF-β receptor or integrin family member. Further investigations are needed for a more complete and detailed picture of T. cruzi invasion.

  10. Endothelial cell motility, coordination and pattern formation during vasculogenesis.

    Science.gov (United States)

    Czirok, Andras

    2013-01-01

    How vascular networks assemble is a fundamental problem of developmental biology that also has medical importance. To explain the organizational principles behind vascular patterning, we must understand how can tissue level structures be controlled through cell behavior patterns like motility and adhesion that, in turn, are determined by biochemical signal transduction processes? We discuss the various ideas that have been proposed as mechanisms for vascular network assembly: cell motility guided by extracellular matrix alignment (contact guidance), chemotaxis guided by paracrine and autocrine morphogens, and multicellular sprouting guided by cell-cell contacts. All of these processes yield emergent patterns, thus endothelial cells can form an interconnected structure autonomously, without guidance from an external pre-pattern. © 2013 Wiley Periodicals, Inc.

  11. Msx1 and Msx2 are expressed in sub-populations of vascular smooth muscle cells.

    Science.gov (United States)

    Goupille, Olivier; Saint Cloment, Cécile; Lopes, Miguel; Montarras, Didier; Robert, Benoît

    2008-08-01

    Using an nlacZ reporter gene inserted at the Msx1 and Msx2 loci, we could analyze the expression of these homeogenes in the adult mouse. We observed that Msx genes are prominently expressed in a subset of blood vessels. The Msx2nlacZ allele is mainly expressed in a restricted population of mural cells in peripheral arteries and veins. Msx1nlacZ is expressed to a lesser extent by vascular smooth muscle cells of peripheral arteries, but is highly expressed in arterioles and capillaries, making Msx1 a novel marker for a subpopulation of pericytes. Expression is set up early in developing vessels and maintained throughout life. In addition, expression of both genes is observed in a few endothelial cells of the aorta at fetal stages, and only Msx2 continues to be expressed in this layer at the adult stage. These results suggest major functions for Msx genes in vascular mural cell formation and remodeling. Copyright (c) 2008 Wiley-Liss, Inc.

  12. Screening and identification of dietary oils and unsaturated fatty acids in inhibiting inflammatory prostaglandin E2 signaling in fat stromal cells

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    Ruan Diana

    2012-08-01

    Full Text Available Abstract Background The molecular mechanisms of dietary oils (such as fish oil and unsaturated fatty acids, which are widely used by the public for anti-inflammation and vascular protection, have not been settled yet. In this study, prostaglandin E2 (PGE2-mediated calcium signaling was used to screen dietary oils and eight unsaturated fatty acids for identification of their anti-inflammatory mechanisms. Isolated fat/stromal cells expressing endogenous PGE2 receptors and an HEK293 cell line specifically expressing the recombinant human PGE2 receptor subtype-1 (EP1 were cultured and used in live cell calcium signaling assays. The different dietary oils and unsaturated fatty acids were used to affect cell signaling under the specific stimulation of a pathological amount of inflammatory PGE2. Results It was identified that fish oil best inhibited the PGE2 signaling in the primary cultured stromal cells. Second, docosahexaenoic acid (DHA, found in abundance in fish oil, was identified as a key factor of inhibition of PGE2 signaling. Eicosapentaenoic acid (EPA, another major fatty acid found in fish oil and tested in this study was found to have small effect on EP1 signaling. The study suggested one of the four PGE2 subtype receptors, EP1 as the key target for the fish oil and DHA target. These findings were further confirmed by using the recombinant EP1 expressed in HEK293 cells as a target. Conclusion This study demonstrated the new mechanism behind the positive effects of dietary fish oils in inhibiting inflammation originates from the rich concentration of DHA, which can directly inhibit the inflammatory EP1-mediated PGE2 receptor signaling, and that the inflammatory response stimulated by PGE2 in the fat stromal cells, which directly related to metabolic diseases, could be down regulated by fish oil and DHA. These findings also provided direct evidence to support the use of dietary oils and unsaturated fatty acids for protection against heart

  13. Angiogenesis, Cancer, and Vascular Aging

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    Junji Moriya

    2017-10-01

    Full Text Available Several lines of evidence have revealed that the angiogenic response to ischemic injury declines with age, which might account for the increased morbidity and mortality of cardiovascular disease (CVD among the elderly. While impairment of angiogenesis with aging leads to delayed wound healing or exacerbation of atherosclerotic ischemic diseases, it also inhibits the progression of cancer. Age-related changes of angiogenesis have been considered to at least partly result from vascular aging or endothelial cell senescence. There is considerable evidence supporting the hypothesis that vascular cell senescence contributes to the pathogenesis of age-related CVD, suggesting that vascular aging could be an important therapeutic target. Since therapeutic angiogenesis is now regarded as a promising concept for patients with ischemic CVD, it has become even more important to understand the detailed molecular mechanisms underlying impairment of angiogenesis in older patients. To improve the usefulness of therapeutic angiogenesis, approaches are needed that can compensate for impaired angiogenic capacity in the elderly while not promoting the development or progression of malignancy. In this review, we briefly outline the mechanisms of angiogenesis and vascular aging, followed by a description of how vascular aging leads to impairment of angiogenesis. We also examine potential therapeutic approaches that could enhance angiogenesis and/or vascular function in the elderly, as well as discussing the possibility of anti-senescence therapy or reversal of endothelial cell senescence.

  14. Viral haemorrhagic fever and vascular alterations.

    Science.gov (United States)

    Aleksandrowicz, P; Wolf, K; Falzarano, D; Feldmann, H; Seebach, J; Schnittler, H

    2008-02-01

    Pathogenesis of viral haemorrhagic fever (VHF) is closely associated with alterations of the vascular system. Among the virus families causing VHF, filoviruses (Marburg and Ebola) are the most fatal, and will be focused on here. After entering the body, Ebola primarily targets monocytes/macrophages and dendritic cells. Infected dendritic cells are largely impaired in their activation potency, likely contributing to the immune suppression that occurs during filovirus infection. Monocytes/macrophages, however, immediately activate after viral contact and release reasonable amounts of cytokines that target the vascular system, particularly the endothelial cells. Some underlying molecular mechanisms such as alteration of the vascular endothelial cadherin/catenin complex, tyrosine phosphorylation, expression of cell adhesion molecules, tissue factor and the effect of soluble viral proteins released from infected cells to the blood stream will be discussed.

  15. BMP signaling regulates satellite cell-dependent postnatal muscle growth.

    Science.gov (United States)

    Stantzou, Amalia; Schirwis, Elija; Swist, Sandra; Alonso-Martin, Sonia; Polydorou, Ioanna; Zarrouki, Faouzi; Mouisel, Etienne; Beley, Cyriaque; Julien, Anaïs; Le Grand, Fabien; Garcia, Luis; Colnot, Céline; Birchmeier, Carmen; Braun, Thomas; Schuelke, Markus; Relaix, Frédéric; Amthor, Helge

    2017-08-01

    Postnatal growth of skeletal muscle largely depends on the expansion and differentiation of resident stem cells, the so-called satellite cells. Here, we demonstrate that postnatal satellite cells express components of the bone morphogenetic protein (BMP) signaling machinery. Overexpression of noggin in postnatal mice (to antagonize BMP ligands), satellite cell-specific knockout of Alk3 (the gene encoding the BMP transmembrane receptor) or overexpression of inhibitory SMAD6 decreased satellite cell proliferation and accretion during myofiber growth, and ultimately retarded muscle growth. Moreover, reduced BMP signaling diminished the adult satellite cell pool. Abrogation of BMP signaling in satellite cell-derived primary myoblasts strongly diminished cell proliferation and upregulated the expression of cell cycle inhibitors p21 and p57 In conclusion, these results show that BMP signaling defines postnatal muscle development by regulating satellite cell-dependent myofiber growth and the generation of the adult muscle stem cell pool. © 2017. Published by The Company of Biologists Ltd.

  16. Identification of cyst nematode B-type CLE peptides and modulation of the vascular stem cell pathway for feeding cell formation.

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    Xiaoli Guo

    2017-02-01

    Full Text Available Stem cell pools in the SAM (shoot apical meristem, RAM (root apical meristem and vascular procambium/cambium are regulated by CLE-receptor kinase-WOX signaling modules. Previous data showed that cyst nematode CLE-like effector proteins delivered into host cells through a stylet, act as ligand mimics of plant A-type CLE peptides and are pivotal for successful parasitism. Here we report the identification of a new class of CLE peptides from cyst nematodes with functional similarity to the B-type CLE peptide TDIF (tracheary element differentiation inhibitory factor encoded by the CLE41 and CLE44 genes in Arabidopsis. We further demonstrate that the TDIF-TDR (TDIF receptor-WOX4 pathway, which promotes procambial meristem cell proliferation, is involved in beet cyst nematode Heterodera schachtii parasitism. We observed activation of the TDIF pathway in developing feeding sites, reduced nematode infection in cle41 and tdr-1 wox4-1 mutants, and compromised syncytium size in cle41, tdr-1, wox4-1 and tdr-1 wox4-1 mutants. By qRT-PCR and promoter:GUS analyses, we showed that the expression of WOX4 is decreased in a clv1-101 clv2-101 rpk2-5 mutant, suggesting that WOX4 is a potential downstream target of nematode CLEs. Exogenous treatment with both nematode A-type and B-type CLE peptides induced massive cell proliferation in wild type roots, suggesting that the two types of CLEs may regulate cell proliferation during feeding site formation. These findings highlight an important role of the procambial cell proliferation pathway in cyst nematode feeding site formation.

  17. Vascular Smooth Muscle Cells From Hypertensive Patient-Derived Induced Pluripotent Stem Cells to Advance Hypertension Pharmacogenomics.

    Science.gov (United States)

    Biel, Nikolett M; Santostefano, Katherine E; DiVita, Bayli B; El Rouby, Nihal; Carrasquilla, Santiago D; Simmons, Chelsey; Nakanishi, Mahito; Cooper-DeHoff, Rhonda M; Johnson, Julie A; Terada, Naohiro

    2015-12-01

    Studies in hypertension (HTN) pharmacogenomics seek to identify genetic sources of variable antihypertensive drug response. Genetic association studies have detected single-nucleotide polymorphisms (SNPs) that link to drug responses; however, to understand mechanisms underlying how genetic traits alter drug responses, a biological interface is needed. Patient-derived induced pluripotent stem cells (iPSCs) provide a potential source for studying otherwise inaccessible tissues that may be important to antihypertensive drug response. The present study established multiple iPSC lines from an HTN pharmacogenomics cohort. We demonstrated that established HTN iPSCs can robustly and reproducibly differentiate into functional vascular smooth muscle cells (VSMCs), a cell type most relevant to vasculature tone control. Moreover, a sensitive traction force microscopy assay demonstrated that iPSC-derived VSMCs show a quantitative contractile response on physiological stimulus of endothelin-1. Furthermore, the inflammatory chemokine tumor necrosis factor α induced a typical VSMC response in iPSC-derived VSMCs. These studies pave the way for a large research initiative to decode biological significance of identified SNPs in hypertension pharmacogenomics. Treatment of hypertension remains suboptimal, and a pharmacogenomics approach seeks to identify genetic biomarkers that could be used to guide treatment decisions; however, it is important to understand the biological underpinnings of genetic associations. Mouse models do not accurately recapitulate individual patient responses based on their genetics, and hypertension-relevant cells are difficult to obtain from patients. Induced pluripotent stem cell (iPSC) technology provides a great interface to bring patient cells with their genomic data into the laboratory and to study hypertensive responses. As an initial step, the present study established an iPSC bank from patients with primary hypertension and demonstrated an effective

  18. Vasoprotection by Dietary Supplements and Exercise: Role of TNFα Signaling

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    Hanrui Zhang

    2012-01-01

    Full Text Available Vascular dysfunction contributes to the pathogenesis of various cardiovascular diseases. Dietary supplements, including fish oil, dietary fibers, and various natural products, and exercise training exert vasoprotective effects. However, the mechanisms underlying the vasoprotective benefits of dietary supplements and physical activity demand extensive investigation. Accumulating evidence suggests that inflammatory cytokine tumor necrosis factor-alpha (TNFα plays a pivotal role in the dysregulation of macrovascular and microvascular function. TNFα induces vascular inflammation, monocyte adhesion to endothelial cells, vascular oxidative stress, apoptosis, and atherogenic response and participates in the regulation of thrombosis and coagulation through multiple signaling pathways involving NFκB, Sp1, activator protein 1, JNK, p38, STAT3, and so forth. Dietary supplements and exercise training decrease TNFα production and ameliorate TNFα-mediated pathological changes in vasculature. Thus, the inhibitory effects of dietary supplements and physical exercise on TNFα production and TNFα signaling may contribute to their vasoprotective properties.

  19. Apoptotic Cells Induced Signaling for Immune Homeostasis in Macrophages and Dendritic Cells

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    Uriel Trahtemberg

    2017-10-01

    Full Text Available Inefficient and abnormal clearance of apoptotic cells (efferocytosis contributes to systemic autoimmune disease in humans and mice, and inefficient chromosomal DNA degradation by DNAse II leads to systemic polyarthritis and a cytokine storm. By contrast, efficient clearance allows immune homeostasis, generally leads to a non-inflammatory state for both macrophages and dendritic cells (DCs, and contributes to maintenance of peripheral tolerance. As many as 3 × 108 cells undergo apoptosis every hour in our bodies, and one of the primary “eat me” signals expressed by apoptotic cells is phosphatidylserine (PtdSer. Apoptotic cells themselves are major contributors to the “anti-inflammatory” nature of the engulfment process, some by secreting thrombospondin-1 (TSP-1 or adenosine monophosphate and possibly other immune modulating “calm-down” signals that interact with macrophages and DCs. Apoptotic cells also produce “find me” and “tolerate me” signals to attract and immune modulate macrophages and DCs that express specific receptors for some of these signals. Neither macrophages nor DCs are uniform, and each cell type may variably express membrane proteins that function as receptors for PtdSer or for opsonins like complement or opsonins that bind to PtdSer, such as protein S and growth arrest-specific 6. Macrophages and DCs also express scavenger receptors, CD36, and integrins that function via bridging molecules such as TSP-1 or milk fat globule-EGF factor 8 protein and that differentially engage in various multi-ligand interactions between apoptotic cells and phagocytes. In this review, we describe the anti-inflammatory and pro-homeostatic nature of apoptotic cell interaction with the immune system. We do not review some forms of immunogenic cell death. We summarize the known apoptotic cell signaling events in macrophages and DCs that are related to toll-like receptors, nuclear factor kappa B, inflammasome, the lipid

  20. Vectorial signalling mechanism required for cell-cell communication during sporulation in Bacillus subtilis.

    Science.gov (United States)

    Diez, Veronica; Schujman, Gustavo E; Gueiros-Filho, Frederico J; de Mendoza, Diego

    2012-01-01

    Spore formation in Bacillus subtilis takes place in a sporangium consisting of two chambers, the forespore and the mother cell, which are linked by pathways of cell-cell communication. One pathway, which couples the proteolytic activation of the mother cell transcription factor σ(E) to the action of a forespore synthesized signal molecule, SpoIIR, has remained enigmatic. Signalling by SpoIIR requires the protein to be exported to the intermembrane space between forespore and mother cell, where it will interact with and activate the integral membrane protease SpoIIGA. Here we show that SpoIIR signal activity as well as the cleavage of its N-terminal extension is strictly dependent on the prespore fatty acid biosynthetic machinery. We also report that a conserved threonine residue (T27) in SpoIIR is required for processing, suggesting that signalling of SpoIIR is dependent on fatty acid synthesis probably because of acylation of T27. In addition, SpoIIR localization in the forespore septal membrane depends on the presence of SpoIIGA. The orchestration of σ(E) activation in the intercellular space by an acylated signal protein provides a new paradigm to ensure local transmission of a weak signal across the bilayer to control cell-cell communication during development. © 2011 Blackwell Publishing Ltd.