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Sample records for cells vascular carriers

  1. Auxin influx carriers control vascular patterning and xylem differentiation in Arabidopsis thaliana.

    Directory of Open Access Journals (Sweden)

    Norma Fàbregas

    2015-04-01

    Full Text Available Auxin is an essential hormone for plant growth and development. Auxin influx carriers AUX1/LAX transport auxin into the cell, while auxin efflux carriers PIN pump it out of the cell. It is well established that efflux carriers play an important role in the shoot vascular patterning, yet the contribution of influx carriers to the shoot vasculature remains unknown. Here, we combined theoretical and experimental approaches to decipher the role of auxin influx carriers in the patterning and differentiation of vascular tissues in the Arabidopsis inflorescence stem. Our theoretical analysis predicts that influx carriers facilitate periodic patterning and modulate the periodicity of auxin maxima. In agreement, we observed fewer and more spaced vascular bundles in quadruple mutants plants of the auxin influx carriers aux1lax1lax2lax3. Furthermore, we show AUX1/LAX carriers promote xylem differentiation in both the shoot and the root tissues. Influx carriers increase cytoplasmic auxin signaling, and thereby differentiation. In addition to this cytoplasmic role of auxin, our computational simulations propose a role for extracellular auxin as an inhibitor of xylem differentiation. Altogether, our study shows that auxin influx carriers AUX1/LAX regulate vascular patterning and differentiation in plants.

  2. The role of the vascular endothelial growth factor/vascular endothelial growth factor receptors axis mediated angiogenesis in curcumin-loaded nanostructured lipid carriers induced human HepG2 cells apoptosis

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    Fengling Wang

    2015-01-01

    Full Text Available Background: Curcumin (diferuloylmethane, the active constituent of turmeric extract has potent anti-cancer properties have been demonstrated in hepatocellular carcinoma (HCC. However, its underlying molecular mechanism of therapeutic effects remains unclear. Vascular endothelial growth factor (VEGF and its receptors (VEGFRs have crucial roles in tumor angiogenesis. Purpose: The goal of this study was to investigate the role of the VEGF/VEGFRs mediated angiogenesis during the proliferation and apoptosis of human HepG2 hepatoma cell line and the effect of curcumin-loaded nanostructured lipid carriers (Cur-NLC. Materials and Methods: The proliferation of HepG2 cells was determined by methyl thiazolyl tetrazolium after exposure to Cur-NLC and native curcumin. Apoptosis was quantified by flow cytometry with annexin V-fluorescein isothiocyanate and propidium iodide staining. Cellular internalization of Cur-NLC was observed by fluorescent microscope. The level of VEGF was detected by enzyme-linked immunosorbent assay kits. The expression of VEGFRs was quantified by Western blotting. Results: Cur-NLC was more effective in inhibiting the proliferation and enhancing the apoptosis of HepG2 cells than native curcumin. Fluorescent microscope analysis showed that HepG2 cells internalized Cur-NLC more effectively than native curcumin. Furthermore, Cur-NLC down-regulated the level of VEGF and the expression of VEGFR-2, but had a slight effect on VEGFR-1. Conclusion: These results clearly demonstrated that Cur-NLC was more effective in anti-cancer activity than the free form of curcumin. These studies demonstrate for the 1 st time that Cur-NLC exerts an antitumor effect on HepG2 cells by modulating VEGF/VEGFRs signaling pathway.

  3. Plasma protein corona modulates the vascular wall interaction of drug carriers in a material and donor specific manner.

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    Daniel J Sobczynski

    Full Text Available The nanoscale plasma protein interaction with intravenously injected particulate carrier systems is known to modulate their organ distribution and clearance from the bloodstream. However, the role of this plasma protein interaction in prescribing the adhesion of carriers to the vascular wall remains relatively unknown. Here, we show that the adhesion of vascular-targeted poly(lactide-co-glycolic-acid (PLGA spheres to endothelial cells is significantly inhibited in human blood flow, with up to 90% reduction in adhesion observed relative to adhesion in simple buffer flow, depending on the particle size and the magnitude and pattern of blood flow. This reduced PLGA adhesion in blood flow is linked to the adsorption of certain high molecular weight plasma proteins on PLGA and is donor specific, where large reductions in particle adhesion in blood flow (>80% relative to buffer is seen with ∼60% of unique donor bloods while others exhibit moderate to no reductions. The depletion of high molecular weight immunoglobulins from plasma is shown to successfully restore PLGA vascular wall adhesion. The observed plasma protein effect on PLGA is likely due to material characteristics since the effect is not replicated with polystyrene or silica spheres. These particles effectively adhere to the endothelium at a higher level in blood over buffer flow. Overall, understanding how distinct plasma proteins modulate the vascular wall interaction of vascular-targeted carriers of different material characteristics would allow for the design of highly functional delivery vehicles for the treatment of many serious human diseases.

  4. Cell-based strategies for vascular regeneration.

    Science.gov (United States)

    Zou, Tongqiang; Fan, Jiabing; Fartash, Armita; Liu, Haifeng; Fan, Yubo

    2016-05-01

    Vascular regeneration is known to play an essential role in the repair of injured tissues mainly through accelerating the repair of vascular injury caused by vascular diseases, as well as the recovery of ischemic tissues. However, the clinical vascular regeneration is still challenging. Cell-based therapy is thought to be a promising strategy for vascular regeneration, since various cells have been identified to exert important influences on the process of vascular regeneration such as the enhanced endothelium formation on the surface of vascular grafts, and the induction of vessel-like network formation in the ischemic tissues. Here are a vast number of diverse cell-based strategies that have been extensively studied in vascular regeneration. These strategies can be further classified into three main categories, including cell transplantation, construction of tissue-engineered grafts, and surface modification of scaffolds. Cells used in these strategies mainly refer to terminally differentiated vascular cells, pluripotent stem cells, multipotent stem cells, and unipotent stem cells. The aim of this review is to summarize the reported research advances on the application of various cells for vascular regeneration, yielding insights into future clinical treatment for injured tissue/organ. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 1297-1314, 2016. PMID:26864677

  5. Vascular inflammatory cells in hypertension

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    DavidG.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.

  6. Pattern formation by vascular mesenchymal cells

    OpenAIRE

    Garfinkel, Alan; Tintut, Yin; Petrasek, Danny; Boström, Kristina; Demer, Linda L.

    2004-01-01

    In embryogenesis, immature mesenchymal cells aggregate and organize into patterned tissues. Later in life, a pathological recapitulation of this process takes place in atherosclerotic lesions, when vascular mesenchymal cells organize into trabecular bone tissue within the artery wall. Here we show that multipotential adult vascular mesenchymal cells self-organize in vitro into patterns that are predicted by a mathematical model based on molecular morphogens interacting in a reaction-diffusion...

  7. Molecular signal transduction in vascular cell apoptosis

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Apoptosis is a form of genetically programmed cell death, which plays a key role in regulation of cellularity in a variety of tissue and cell types including the cardiovascular tissues. Under both physiological and pathophysiological conditions, various biophysiological and biochemical factors, including mechanical forces, reactive oxygen and nitrogen species, cytokines, growth factors, oxidized lipoproteins, etc., may influence apoptosis of vascular cells. The Fas/Fas ligand/caspase death-signaling pathway, Bcl-2 protein family/mitochondria, the tumor suppressive gene p53, and the proto-oncogene c-myc may be activated in atherosclerotic lesions, and mediates vascular apoptosis during the development of atherosclerosis. Abnormal expression and dysfunction of these apoptosis-regulating genes may attenuate or accelerate vascular cell apoptosis and affect the integrity and stability of atherosclerotic plaques. Clarification of the molecular mechanism that regulates apoptosis may help design a new strategy for treatment of atherosclerosis and its major complication, the acute vascular syndromes.

  8. T cells in vascular inflammatory diseases

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    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.

  9. Advance in molecular imaging research of vascular smooth muscle cells in the vascular diseases

    International Nuclear Information System (INIS)

    Vascular smooth muscle cells (VSMCs) are the primary cells within the vascular wall structure and maintain the tension of blood vessels, playing a key role in the restenosis, atherosclerosis and some other vascular diseases. With the development of molecular imaging, VSMCs cellular level of imaging studies is becoming more and more attention. The phenotype modulation, proliferation, migration and molecular imaging research progress of VSMCs in pathologic state were reviewed, to improve the management of vascular restenosis and atherosclerosis. (authors)

  10. Stimulation of vascular cells by extracellular signals - A biophysical analysis

    OpenAIRE

    Biela, Sarah A.

    2009-01-01

    Stimulation of vascular cells by extracellullar signals Treatment of vascular diseases often requires the selective addressing of endothelial (ECs) and smooth muscle cells (SMCs). The two vascular cell types are important for the wound healing after stent implantation. Recent research designs new materials and coatings for stents to improve the complex healing process. The aim of my work was to find and investigate different reactions in the two vascular cell types (ECs and SMCs) through surf...

  11. Simulations of magnetic capturing of drug carriers in the brain vascular system

    International Nuclear Information System (INIS)

    Highlights: ► Blood flow and magnetic particles distributions in the brain vascular system simulated. ► Numerical mesh generated from raw MRI images. ► Significant increase in local capturing of magnetic particles obtained. ► Promising technique for localised non-invasive treatment of brain tumours. - Abstract: The present paper reports on numerical simulations of blood flow and magnetic drug carrier distributions in a complex brain vascular system. The blood is represented as a non-Newtonian fluid by the generalised power law. The Lagrangian tracking of the double-layer spherical particles is performed to estimate particle deposition under influence of imposed magnetic field gradients across arterial walls. Two situations are considered: neutral (magnetic field off) and active control (magnetic field on) case. The double-layer spherical particles that mimic a real medical drug are characterised by two characteristic diameters - the outer one and the inner one of the magnetic core. A numerical mesh of the brain vascular system consisting of multi-branching arteries is generated from raw MRI scan images of a patient. The blood is supplied through four main inlet arteries and the entire vascular system includes more than 30 outlets, which are modelled by Murray’s law. The no-slip boundary condition is applied for velocity components along the smooth and rigid arterial walls. Numerical simulations revealed detailed insights into blood flow patterns, wall-shear-stress and local particle deposition efficiency along arterial walls. It is demonstrated that magnetically targeted drug delivery significantly increased the particle capturing efficiency in the pre-defined regions. This feature can be potentially useful for localised, non-invasive treatment of brain tumours.

  12. Optoelectronic characterization of carrier extraction in a hot carrier photovoltaic cell structure

    Science.gov (United States)

    Dimmock, James A. R.; Kauer, Matthias; Smith, Katherine; Liu, Huiyun; Stavrinou, Paul N.; Ekins-Daukes, Nicholas J.

    2016-07-01

    A hot carrier photovoltaic cell requires extraction of electrons on a timescale faster than they can lose energy to the lattice. We optically and optoelectronically characterize two resonant tunneling structures, showing their compatability with hot carrier photovoltaic operation, demonstrating structural and carrier extraction properties necessary for such a device. In particular we use time resolved and temperature dependent photoluminescence to determine extraction timescales and energy levels in the structures and demonstrate fast carrier extraction by tunneling. We also show that such devices are capable of extracting photo-generated electrons at high carrier densities, with an open circuit voltage in excess of 1 V.

  13. Molecular Mechanisms for Vascular Development and Secondary Cell Wall Formation

    OpenAIRE

    Yang, Jung Hyun; Wang, Huanzhong

    2016-01-01

    Vascular tissues are important for transporting water and nutrients throughout the plant and as physical support of upright growth. The primary constituents of vascular tissues, xylem, and phloem, are derived from the meristematic vascular procambium and cambium. Xylem cells develop secondary cell walls (SCWs) that form the largest part of plant lignocellulosic biomass that serve as a renewable feedstock for biofuel production. For the last decade, research on vascular development and SCW bio...

  14. Hot carrier solar cell absorbers: investigation of carrier cooling properties of candidate materials

    Science.gov (United States)

    Conibeer, G.; Shrestha, Santosh; Huang, Shujuan; Patterson, Robert; Xia, Hongze; Feng, Yu; Zhang, Pengfei; Gupta, Neeti; Smyth, Suntrana; Liao, Yuanxun; Lin, Shu; Wang, Pei; Dai, Xi; Chung, Simon; Yang, Jianfeng; Zhang, Yi

    2015-09-01

    The hot carrier cell aims to extract the electrical energy from photo-generated carriers before they thermalize to the band edges. Hence it can potentially achieve a high current and a high voltage and hence very high efficiencies up to 65% under 1 sun and 86% under maximum concentration. To slow the rate of carrier thermalisation is very challenging, but modification of the phonon energies and the use of nanostructures are both promising ways to achieve some of the required slowing of carrier cooling. A number of materials and structures are being investigated with these properties and test structures are being fabricated. Initial measurements indicate slowed carrier cooling in III-Vs with large phonon band gaps and in multiple quantum wells. It is expected that soon proof of concept of hot carrier devices will pave the way for their development to fully functioning high efficiency solar cells.

  15. Detachment factors for enhanced carrier to carrier transfer of CHO cell lines on macroporous microcarriers

    OpenAIRE

    Landauer, K.; Dürrschmid, M.; Klug, H.; Wiederkum, S.; Blüml, G.; Doblhoff-Dier, O.

    2002-01-01

    In this publication different detachment factors were tested for enhancing carrier to carrier transfer for scale-up of macroporous microcarrier based bioprocesses. Two Chinese hamster ovary cell lines, CHO-K1 and a genetically engineered CHO-K1 derived cell line (CHO-MPS), producing recombinant human Arylsulfatase B, were examined. The cells were grown on Cytoline 1microcarriers (Amersham Biosciences, Uppsala, Sweden) in protein-free and chemically defined medium respectively. Fully colonised...

  16. Human Vascular Endothelium from Induced Pluripotent Stem Cells

    OpenAIRE

    Adams, William James

    2013-01-01

    The vascular endothelium is a dynamic cellular interface that displays a unique phenotypic plasticity. This plasticity is critical for vascular function and when dysregulated is pathogenic in several diseases. The development of new human endothelial genotype-phenotype studies, personalized vascular medicine efforts and cell based regenerative therapies are limited by the unavailability of patient-specific endothelial cells. Induced pluripotent stem cells (iPSC) offer great promise as a new p...

  17. In vitro differentiation of porcine aortic vascular precursor cells to endothelial and vascular smooth muscle cells.

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    Zaniboni, Andrea; Bernardini, Chiara; Bertocchi, Martina; Zannoni, Augusta; Bianchi, Francesca; Avallone, Giancarlo; Mangano, Chiara; Sarli, Giuseppe; Calzà, Laura; Bacci, Maria Laura; Forni, Monica

    2015-09-01

    Recent findings suggest that progenitor and multipotent mesenchymal stromal cells (MSCs) are associated with vascular niches. Cells displaying mesenchymal properties and differentiating to whole components of a functional blood vessel, including endothelial and smooth muscle cells, can be defined as vascular stem cells (VSCs). Recently, we isolated a population of porcine aortic vascular precursor cells (pAVPCs), which have MSC- and pericyte-like properties. The aim of the present work was to investigate whether pAVPCs possess VSC-like properties and assess their differentiation potential toward endothelial and smooth muscle lineages. pAVPCs, maintained in a specific pericyte growth medium, were cultured in high-glucose DMEM + 10% FBS (long-term medium, LTM) or in human endothelial serum-free medium + 5% FBS and 50 ng/ml of hVEGF (endothelial differentiation medium, EDM). After 21 days of culture in LTM, pAVPCs showed an elongated fibroblast-like morphology, and they seem to organize in cord-like structures. qPCR analysis of smooth muscle markers [α-smooth muscle actin (α-SMA), calponin, and smooth muscle myosin (SMM) heavy chain] showed a significant increment of the transcripts, and immunofluorescence analysis confirmed the presence of α-SMA and SMM proteins. After 21 days of culture in EDM, pAVPCs displayed an endothelial cell-like morphology and revealed the upregulation of the expression of endothelial markers (CD31, vascular endothelial-cadherin, von Willebrand factor, and endothelial nitric oxide synthase) showing the CD31-typical pattern. In conclusion, pAVPCs could be defined as a VSC-like population considering that, if they are maintained in a specific pericyte medium, they express MSC markers, and they have, in addition to the classical mesenchymal trilineage differentiation potential, the capacity to differentiate in vitro toward the smooth muscle and the endothelial cell phenotypes. PMID:26135800

  18. 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

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

    OpenAIRE

    Ningning He; Lu Zhang; Jian Cui; Zongjin Li

    2014-01-01

    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 rev...

  20. Cell carriers for oncolytic viruses: current challenges and future directions.

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    Roy, Dominic G; Bell, John C

    2013-01-01

    The optimal route for clinical delivery of oncolytic viruses is thought to be systemic intravenous injection; however, the immune system is armed with several highly efficient mechanisms to remove pathogens from the circulatory system. To overcome the challenges faced in trying to delivery oncolytic viruses specifically to tumors via the bloodstream, carrier cells have been investigated to determine their suitability as delivery vehicles for systemic administration of oncolytic viruses. Cell carriers protect viruses from neutralization, one of the most limiting aspects of oncolytic virus interaction with the immune system. Cell carriers can also possess inherent tumor tropism, thus directing the delivery of the virus more specifically to a tumor. With preclinical studies already demonstrating the success and feasibility of this approach with multiple oncolytic viruses, clinical evaluation of cell-mediated delivery of viruses is on the horizon. Meanwhile, ongoing preclinical studies are aimed at identifying new cellular vehicles for oncolytic viruses and improving current promising cell carrier platforms. PMID:27512657

  1. Apoptosis and calcification of vascular endothelial cell under hyperhomocysteinemia.

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    Fang, Kuaifa; Chen, Zhujun; Liu, Meng; Peng, Jian; Wu, Pingsheng

    2015-01-01

    In recent years, it is found that increase in Hcy level in blood can directly or indirectly cause vascular endothelial cell injury and induce vascular calcification. However, the mechanism of vascular endothelial cell injury and vascular calcification has not been studied thoroughly. This paper carried out experiment for research aiming at discussing the effect and action mechanism of Hhcy on endothelial cells and vascular calcification. Firstly, human umbilical vein endothelial cells (HUVECs) were cultured and then intervened by Hcy of different concentrations (0, 0.01, 0.1, 1.0, 3.0, 5.0 mmol/L) and at different action time (3, 6, 12, 24 h). Then apoptosis rate and reactive oxygen were detected by flow cytometry. At the same time, the model for the culture of rat vascular calcification was set up and induced into Hhcy so as to detect the total plasma Hcy level and judge vascular calcification degree. The results showed that with the increase in Hcy concentration and extension of action period, the apoptosis rate and generation of reactive oxygen of HUVECs all significantly increased, and the differences were all statistically significant (P animal calcification model, mass of black particle deposition was seen after Von Kossa staining of rat vessels in calcification group. Compared with the control group, the vascular calcium content, alkaline phosphatase activity and osteocalcin content in calcification group all increased (P benefits on clinical prevention works. PMID:25476479

  2. Vascular mimicry in cultured head and neck tumour cell lines

    OpenAIRE

    Upile, Tahwinder; Jerjes, Waseem; Radhi, Hani; Al-Khawalde, Mohammed; Kafas, Panagiotis; Nouraei, Seyed; Sudhoff, Holger

    2011-01-01

    Introduction Vascuologenesis is the de novo establishment of blood vessels and vascular networks from mesoderm-derived endothelial cell precursors (angioblasts). Recently a novel mechanism, by which some genetically deregulated and aggressive tumour cells generate "micro-vascular" channels without the participation of endothelial cells and independent of angiogenesis, has been proposed. This has been termed "vasculogenic mimicry" and has implications beyond angiogenesis and adds another layer...

  3. Vascular progenitor cells in arterial remodeling

    OpenAIRE

    Grudzinska, Monika K.

    2011-01-01

    Cardiovascular disease is the leading cause of global mortality and physical disability mainly due to the complications such as myocardial infarction or stroke. Physiological healing reaction takes place in the diseased vessel wall aimed to repair the vessel after an injury. There are two factors essentially important for clinical improvement of vascular diseases. The first one is protection of the vascular damage, and the second one is repair of injured, ischemic and regenerating tissues to ...

  4. Fundamental limitations of hot-carrier solar cells

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    Kirk, A. P.; Fischetti, M. V.

    2012-10-01

    Sunlight-generated hot-carrier transport in strongly absorbing direct band-gap GaAs—among the most optimal of semiconductors for high-efficiency solar cells—is simulated with an accurate full-band structure self-consistent Monte Carlo method, including short- and long-range Coulomb interaction, impact ionization, and optical and acoustic phonon scattering. We consider an ultrapure 100-nm-thick intrinsic GaAs absorber layer designed with quasiballistic carrier transport that achieves complete photon absorption down to the band edge by application of careful light trapping and that has a generous hot-carrier retention time of 10 ps prior to the onset of carrier relaxation. We find that hot-carrier solar cells can be severely limited in performance due to the substantially reduced current density caused by insufficient extraction of the widely distributed hot electrons (holes) through the requisite energy selective contacts.

  5. Piperine Congeners as Inhibitors of Vascular Smooth Muscle Cell Proliferation.

    Science.gov (United States)

    Mair, Christina E; Liu, Rongxia; Atanasov, Atanas G; Wimmer, Laurin; Nemetz-Fiedler, Daniel; Sider, Nadine; Heiss, Elke H; Mihovilovic, Marko D; Dirsch, Verena M; Rollinger, Judith M

    2015-08-01

    Successful vascular healing after percutaneous coronary interventions is related to the inhibition of abnormal vascular smooth muscle cell proliferation and efficient re-endothelialization. In the search for vascular smooth muscle cell anti-proliferative agents from natural sources we identified piperine (1), the main pungent constituent of the fruits from Piper nigrum (black pepper). Piperine inhibited vascular smooth muscle cell proliferation with an IC50 of 21.6 µM, as quantified by a resazurin conversion assay. Investigations of ten piperamides isolated from black pepper fruits and 15 synthesized piperine derivatives resulted in the identification of three potent vascular smooth muscle cell proliferation inhibitors: the natural alkaloid pipertipine (4), and the two synthetic derivatives (2E,4E)-N,N-dibutyl-5-(3,5-dimethoxyphenyl)penta-2,4-dienamide (14) and (E)-N,N-dibutyl-3-(naphtho[2,3-d][1,3]dioxol-5-yl)acrylamide (20). They showed IC50 values of 3.38, 6.00, and 7.85 µM, respectively. Furthermore, the synthetic compound (2E,4E)-5-(4-fluorophenyl)-1-(piperidin-1-yl)penta-2,4-dien-1-one (12) was found to be cell type selective, by inhibiting vascular smooth muscle cell proliferation with an IC50 of 11.8 µM without influencing the growth of human endothelial cells. PMID:26132851

  6. Characterisation of resident multipotent vascular stem cell derived smooth muscle cells in culture

    OpenAIRE

    Kennedy, Eimear

    2015-01-01

    The origin of the vascular Smooth Muscle Cell (SMC) involved with vascular remodelling is very controversial. The theory that SMCs can dedifferentiate is long standing. However, in more recent years this idea has been challenged with the emergence of resident progenitor stem cells in the vascular wall. Here, a population of primary Multipotent Vascular Stem Cells (MVSCs) were isolated using explant culture from the medial layer of rat aortic tissue. MVSCs were characterised for multipotency b...

  7. 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. PMID:26965667

  8. 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...

  9. 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.

  10. Cell carriers for oncolytic viruses: current challenges and future directions

    Directory of Open Access Journals (Sweden)

    Roy DG

    2013-10-01

    Full Text Available Dominic G Roy,1,2 John C Bell1–31Centre for Innovative Cancer Therapeutics, Ottawa Hospital Research Institute, 2Department of Biochemistry, Immunology and Microbiology, 3Department of Medicine, University of Ottawa, Ottawa, ON, CanadaAbstract: The optimal route for clinical delivery of oncolytic viruses is thought to be systemic intravenous injection; however, the immune system is armed with several highly efficient mechanisms to remove pathogens from the circulatory system. To overcome the challenges faced in trying to delivery oncolytic viruses specifically to tumors via the bloodstream, carrier cells have been investigated to determine their suitability as delivery vehicles for systemic administration of oncolytic viruses. Cell carriers protect viruses from neutralization, one of the most limiting aspects of oncolytic virus interaction with the immune system. Cell carriers can also possess inherent tumor tropism, thus directing the delivery of the virus more specifically to a tumor. With preclinical studies already demonstrating the success and feasibility of this approach with multiple oncolytic viruses, clinical evaluation of cell-mediated delivery of viruses is on the horizon. Meanwhile, ongoing preclinical studies are aimed at identifying new cellular vehicles for oncolytic viruses and improving current promising cell carrier platforms.Keywords: oncolytic virus, cell carrier, systemic delivery, tumor targeting, cancer

  11. Local Augmented Angiotensinogen Secreted from Apoptotic Vascular Endothelial Cells Is a Vital Mediator of Vascular Remodelling.

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    Shyh-Jong Wu

    Full Text Available Vascular remodelling is a critical vasculopathy found in atheromatous diseases and allograft failures. The local renin angiotensin system (RAS has been implicated in vascular remodelling. However, the mechanisms by which the augmented local RAS is associated with the initial event of endothelial cell apoptosis in injured vasculature remain undefined. We induced the apoptosis of human umbilical vein endothelial cells (HUVECs and vascular smooth muscle cells (VSMCs through serum starvation (SS. After the cells were subjected to SS, we found that the mRNA expression of angiotensinogen (AGT was increased by >3-fold in HUVECs and by approximately 2.5-fold in VSMCs. In addition, the expression of angiotensin-converting enzyme (ACE mRNA was increased in VSMCs but decreased to 50% in HUVECs during the same apoptotic process. Increases in the expression of AGT protein and angiotensin II (Ang II were found in a serum-free medium conditioned by HUVECs (SSC. The increased Ang II was suppressed using lisinopril (an ACE inhibitor treatment. Moreover, the activation of ERK1/2 induced by the SSC in VSMCs was also suppressed by losartan. In conclusion, we first demonstrated that the augmented AGT released from apoptotic endothelial cells acts as a vital progenitor of Ang II to accelerate vascular remodelling, and we suggest that blocking local augmented Ang II might be an effective strategy for restraining intimal hyperplasia.

  12. Ancestral vascular lumen formation via basal cell surfaces.

    Directory of Open Access Journals (Sweden)

    Tomás Kucera

    Full Text Available The cardiovascular system of bilaterians developed from a common ancestor. However, no endothelial cells exist in invertebrates demonstrating that primitive cardiovascular tubes do not require this vertebrate-specific cell type in order to form. This raises the question of how cardiovascular tubes form in invertebrates? Here we discovered that in the invertebrate cephalochordate amphioxus, the basement membranes of endoderm and mesoderm line the lumen of the major vessels, namely aorta and heart. During amphioxus development a laminin-containing extracellular matrix (ECM was found to fill the space between the basal cell surfaces of endoderm and mesoderm along their anterior-posterior (A-P axes. Blood cells appear in this ECM-filled tubular space, coincident with the development of a vascular lumen. To get insight into the underlying cellular mechanism, we induced vessels in vitro with a cell polarity similar to the vessels of amphioxus. We show that basal cell surfaces can form a vascular lumen filled with ECM, and that phagocytotic blood cells can clear this luminal ECM to generate a patent vascular lumen. Therefore, our experiments suggest a mechanism of blood vessel formation via basal cell surfaces in amphioxus and possibly in other invertebrates that do not have any endothelial cells. In addition, a comparison between amphioxus and mouse shows that endothelial cells physically separate the basement membranes from the vascular lumen, suggesting that endothelial cells create cardiovascular tubes with a cell polarity of epithelial tubes in vertebrates and mammals.

  13. The adhesion receptor CD44 promotes atherosclerosis by mediating inflammatory cell recruitment and vascular cell activation

    OpenAIRE

    Cuff, Carolyn A.; Kothapalli, Devashish; Azonobi, Ijeoma; Chun, Sam; Zhang, Yuanming; Belkin, Richard; Yeh, Christine; Secreto, Anthony; Richard K Assoian; Rader, Daniel J; Puré, Ellen

    2001-01-01

    Atherosclerosis causes most acute coronary syndromes and strokes. The pathogenesis of atherosclerosis includes recruitment of inflammatory cells to the vessel wall and activation of vascular cells. CD44 is an adhesion protein expressed on inflammatory and vascular cells. CD44 supports the adhesion of activated lymphocytes to endothelium and smooth muscle cells. Furthermore, ligation of CD44 induces activation of both inflammatory and vascular cells. To assess the potential contribution of CD4...

  14. Effects of Estrogen Level on the Function of Vascular Endothelial Cells and Expression of Vascular Cell Adhesion Molecule - 1φ

    Institute of Scientific and Technical Information of China (English)

    WU Saizhu(吴赛珠); LIU Jiangguo(刘建国); TAN Jiayu(谭家余); ZHoU Kexiang(周可祥); Gorge D Webb; WEI Heming(隗和明); GUO Zhiguang(郭志刚)

    2002-01-01

    Objectives To ob- serve the effect of different estrogen levels on the se- cretory function of vascular endothelial cells of female rats, and study the effect of modulation of estrogen level on the expression of vascular cell adhesion molecule - 1 and the concentration of estrogen receptorin vascular endothelial cells. Methods Radioim-munology was used to measure the serum concentrationof endothelin and PGI2, and copper-cadmium re-duction was employed to measure the serum content ofnitrogen monoxide. Radioligand binding and flowcy-tometry were used to measure the expression of estrogenreceptor and vascular cell adhesion molecule (VCAM-1 ) of vascular endothelial cells respectively. Re-sults 1. The serum concentration of nitric oxide andPGI2 decreased when the ovaries of female rats wereremoved. In ovariectomized rats, given estrogen, theconcentration rose ( P < 0.05), but the plasma con-centration of endothelin was adverse to it. 2. Theconcentration of estrogen receptor of vascular endothe-lial cells decreased remarkably when the ovaries of fe-male rats were removed. When given estrogen, it in-creased. 3. The percent of expressed VCAM - 1 in-creased siguificantly after interleukin- lβoperated onthe cells, but 17 - βestradiol at 3 × 10-8 ~ 10-6 mol/lall decreased the percent. Conclusions Estrogenlevel can influence the secretion of nitrogen monoxide,PGI2 and endothlin of vascular endothelial cells, andalso influence the concentration of estrogen receptor ofvascular endothelial cells. 17 -β Estradiol at 3 × 10-8~ 10-6 M can decrease the elevation of VCAM - 1 ofvascular endothelial cells induced by interleukin - 1 β.

  15. Accelerating Vascularization in Polycaprolactone Scaffolds by Endothelial Progenitor Cells

    OpenAIRE

    Singh, Shivani; Wu, Benjamin M.; Dunn, James C.Y.

    2011-01-01

    Vascularization is a major challenge in tissue engineering. The purpose of this study is to expedite the formation of blood vessels in porous polycaprolactone (PCL) scaffolds by the delivery of endothelial progenitor cells (EPCs). To establish a pro-angiogenic and pro-vasculogenic microenvironment, we employed EPCs seeded in PCL scaffold with surface-immobilized heparin and vascular endothelial growth factor (VEGF). EPCs seeded on scaffolds with VEGF exhibited phosphorylation of the receptor....

  16. NREL Studies Carrier Separation and Transport in Perovskite Solar Cells

    Energy Technology Data Exchange (ETDEWEB)

    2016-01-01

    NREL scientists studied charge separation and transport in perovskite solar cells by determining the junction structure across the solar device using the nanoelectrical characterization technique of Kelvin probe force microscopy. The distribution of electrical potential across both planar and porous devices demonstrates a p-n junction structure at the interface between titanium dioxide and perovskite. In addition, minority-carrier transport within the devices operates under diffusion/drift. Clarifying the fundamental junction structure provides significant guidance for future research and development. This NREL study points to the fact that improving carrier mobility is a critical factor for continued efficiency gains in perovskite solar cells.

  17. 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.

  18. Vinpocetine suppresses pathological vascular remodeling by inhibiting vascular smooth muscle cell proliferation and migration.

    Science.gov (United States)

    Cai, Yujun; Knight, Walter E; Guo, Shujie; Li, Jian-Dong; Knight, Peter A; Yan, Chen

    2012-11-01

    Abnormal vascular smooth muscle cell (SMC) activation is associated with various vascular disorders such as atherosclerosis, in-stent restenosis, vein graft disease, and transplantation-associated vasculopathy. Vinpocetine, a derivative of the alkaloid vincamine, has long been used as a cerebral blood flow enhancer for treating cognitive impairment. However, its role in pathological vascular remodeling remains unexplored. Herein, we show that systemic administration of vinpocetine significantly reduced neointimal formation in carotid arteries after ligation injury. Vinpocetine also markedly decreased spontaneous remodeling of human saphenous vein explants in ex vivo culture. In cultured SMCs, vinpocetine dose-dependently suppressed cell proliferation and caused G1-phase cell cycle arrest, which is associated with a decrease in cyclin D1 and an increase in p27Kip1 levels. In addition, vinpocetine dose-dependently inhibited platelet-derived growth factor (PDGF)-stimulated SMC migration as determined by the two-dimensional migration assays and three-dimensional aortic medial explant invasive assay. Moreover, vinpocetine significantly reduced PDGF-induced type I collagen and fibronectin expression. It is noteworthy that PDGF-stimulated phosphorylation of extracellular signal-regulated kinases 1/2 (ERK1/2), but not protein kinase B, was specifically inhibited by vinpocetine. Vinpocetine powerfully attenuated intracellular reactive oxidative species (ROS) production, which largely mediates the inhibitory effects of vinpocetine on ERK1/2 activation and SMC growth. Taken together, our results reveal a novel function of vinpocetine in attenuating neointimal hyperplasia and pathological vascular remodeling, at least partially through suppressing ROS production and ERK1/2 activation in SMCs. Given the safety profile of vinpocetine, this study provides insight into the therapeutic potential of vinpocetine in proliferative vascular disorders. PMID:22915768

  19. Carbon nanotubes: an emerging drug carrier for targeting cancer cells.

    Science.gov (United States)

    Rastogi, Vaibhav; Yadav, Pragya; Bhattacharya, Shiv Sankar; Mishra, Arun Kumar; Verma, Navneet; Verma, Anurag; Pandit, Jayanta Kumar

    2014-01-01

    During recent years carbon nanotubes (CNTs) have been attracted by many researchers as a drug delivery carrier. CNTs are the third allotropic form of carbon-fullerenes which were rolled into cylindrical tubes. To be integrated into the biological systems, CNTs can be chemically modified or functionalised with therapeutically active molecules by forming stable covalent bonds or supramolecular assemblies based on noncovalent interactions. Owing to their high carrying capacity, biocompatibility, and specificity to cells, various cancer cells have been explored with CNTs for evaluation of pharmacokinetic parameters, cell viability, cytotoxicty, and drug delivery in tumor cells. This review attempts to highlight all aspects of CNTs which render them as an effective anticancer drug carrier and imaging agent. Also the potential application of CNT in targeting metastatic cancer cells by entrapping biomolecules and anticancer drugs has been covered in this review. PMID:24872894

  20. Specialized mouse embryonic stem cells for studying vascular development

    Directory of Open Access Journals (Sweden)

    Glaser DE

    2014-10-01

    Full Text Available Drew E Glaser,1 Andrew B Burns,2 Rachel Hatano,2 Magdalena Medrzycki,3 Yuhong Fan,3 Kara E McCloskey1 1School of Engineering, University of California, Merced, CA, USA; 2School of Natural Sciences, University of California, Merced, CA, USA; 3School of Biology and the Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA, USAAbstract: 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

  1. The Effect of Polymeric Nanoparticles on Biocompatibility of Carrier Red Blood Cells.

    Directory of Open Access Journals (Sweden)

    Daniel Pan

    Full Text Available Red blood cells (RBCs can be used for vascular delivery of encapsulated or surface-bound drugs and carriers. Coupling to RBC prolongs circulation of nanoparticles (NP, 200 nm spheres, a conventional model of polymeric drug delivery carrier enabling their transfer to the pulmonary vasculature without provoking overt RBC elimination. However, little is known about more subtle and potentially harmful effects of drugs and drug carriers on RBCs. Here we devised high-throughput in vitro assays to determine the sensitivity of loaded RBCs to osmotic stress and other damaging insults that they may encounter in vivo (e.g. mechanical, oxidative and complement insults. Sensitivity of these tests is inversely proportional to RBC concentration in suspension and our results suggest that mouse RBCs are more sensitive to damaging factors than human RBCs. Loading RBCs by NP at 1:50 ratio did not affect RBCs, while 10-50 fold higher NP load accentuated RBC damage by mechanical, osmotic and oxidative stress. This extensive loading of RBC by NP also leads to RBCs agglutination in buffer; however, addition of albumin diminished this effect. These results provide a template for analyses of the effects of diverse cargoes loaded on carrier RBCs and indicate that: i RBCs can tolerate carriage of NP at doses providing loading of millions of nanoparticles per microliter of blood; ii tests using protein-free buffers and mouse RBCs may overestimate adversity that may be encountered in humans.

  2. Modulation of human vascular endothelial cell behaviors by nanotopographic cues.

    Science.gov (United States)

    Liliensiek, Sara J; Wood, Joshua A; Yong, Jiang; Auerbach, Robert; Nealey, Paul F; Murphy, Christopher J

    2010-07-01

    Basement membranes possess a complex three-dimensional topography in the nanoscale and submicron range which have been shown to profoundly modulate a large menu of fundamental cell behaviors. Using the topographic features found in native vascular endothelial basement membranes as a guide, polyurethane substrates were fabricated containing anisotropically ordered ridge and groove structures and isotropically ordered pores from 200 nm to 2000 nm in size. We investigated the impact of biomimetic length-scale topographic cues on orientation/elongation, proliferation and migration on four human vascular endothelial cell-types from large and small diameter vessels. We found that all cell-types exhibited orientation and alignment with the most pronounced response on anisotropically ordered ridges > or =800 nm. HUVEC cells were the only cell-type examined to demonstrate a decrease in proliferation in response to the smallest topographic features regardless of surface order. On anisotropically ordered surfaces all cell-types migrated preferentially parallel to the long axis of the ridges, with the greatest increase in cell migration being observed on the 1200 nm pitch. In contrast, cells did not exhibit any preference in direction or increase in migration speed on isotropically ordered surfaces. Overall, our data demonstrate that surface topographic features impact vascular endothelial cell behavior and that the impact of features varies with the cell behavior being considered, topographic feature scale, surface order, and the anatomic origin of the cell being investigated. PMID:20400175

  3. Vascular Potential of Human Pluripotent Stem Cells

    OpenAIRE

    Iacobas, Ionela; Vats, Archana; Hirschi, Karen K.

    2010-01-01

    Cardiovascular disease is the number one cause of death and disability in the US. Understanding the biological activity of stem and progenitor cells, and their ability to contribute to the repair, regeneration and remodeling of the heart and blood vessels affected by pathologic processes is an essential part of the paradigm in enabling us to achieve a reduction in related deaths. Both human embryonic stem (ES) cells and induced pluripotent stem (iPS) cells are promising sources of cells for c...

  4. Inhibition of apoptotic signaling in spermine-treated vascular smooth muscle cells by a novel glutathione precursor

    OpenAIRE

    Sinha-Hikim, Indrani; Shen, Ruoqing; Kovacheva, Ekaterina; Crum, Albert; Vaziri, Nosratola D.; Norris, Keith C.

    2010-01-01

    Chronic kidney disease (CKD) is a public health problem, mediated by hemodynamic and non-hemodynamic events including oxidative stress. We investigated the effect of two glutathione (GSH) precursors, N-acetyl-cysteine (NAC) and cystine as the physiologic carrier of cysteine in GSH with added selenomethionine (F1) in preventing spermine (uremic toxin) induced apoptosis in cultured human aortic vascular smooth muscle cells (VSMC). VSMCs exposed to spermine (15 μM) with or without antioxidants (...

  5. Cancer stem cell-vascular endothelial cell interactions in glioblastoma.

    Science.gov (United States)

    Sharma, Aman; Shiras, Anjali

    2016-05-01

    Glioblastoma (GBM), a higher grade glial tumor, is highly aggressive, therapy resistant and often shows poor patient prognosis due to frequent recurrence. These features of GBM are attributed to presence of a significantly smaller proportion of glioma stem cells (GSCs) that are endowed with self-renewal ability, multi-potent nature and show resistance to therapy in patients. GSCs preferably take shelter close to tumor vasculature due to paracrine need of soluble factors secreted by endothelial cells (ECs) of vasculature. The physical proximity of GSCs to ECs creates a localized perivascular niche where mutual GSC-EC interactions regulate GSC stemness, migration, therapy resistance, and cellular kinetics during tumor growth. Together, perivascular niche presents a therapeutically targetable tumor structure for clinical management of GBM. Thus, understanding cellular and non-cellular components in perivascular niche is vital for designing in vitro and in vivo GBM tumor models. Here, we discuss the components and structure of tumor vascular niche and its impact on tumor progression. PMID:26692486

  6. Establishment of the model of vascular endothelial cell membrane chromatography and its preliminary application

    Institute of Scientific and Technical Information of China (English)

    LI YiPing; HE LangChong

    2007-01-01

    A model of vascular endothelial cell membrane chromatography was established by using an ECV304 cell membrane stationary phase (ECV304 CMSP) prepared by immobilizing the ECV304 cell membrane onto the surface of silica carrier. The surface and chromatographic characteristics of ECV304 CMSP were studied. The active component from Caulophyllum robustum was screened by using the model of vascular endothelial cell membrane chromatography. The interaction between the active component and membrane receptor was determined by using a replace experiments. The effect of the active component was tested by using tube formation of ECV304 cell. The results indicated that the model of ECV304 cell membrane chromatograph (ECV304 CMC) can stimulate the interaction between drug and receptor in vitro and the retention characteristics of taspine as active component was similar to that of model molecule in the model of ECV304 CMC. And therefore, taspine acted on VEGFR2 and inhibited the tube formation of ECV304 cell induced by VEGF. This model can be used to screen definite active component as a screening model.

  7. Beta-cell mitochondrial carriers and the diabetogenic stress response.

    Science.gov (United States)

    Brun, Thierry; Maechler, Pierre

    2016-10-01

    Mitochondria play a central role in pancreatic beta-cells by coupling metabolism of the secretagogue glucose to distal events of regulated insulin exocytosis. This process requires transports of both metabolites and nucleotides in and out of the mitochondria. The molecular identification of mitochondrial carriers and their respective contribution to beta-cell function have been uncovered only recently. In type 2 diabetes, mitochondrial dysfunction is an early event and may precipitate beta-cell loss. Under diabetogenic conditions, characterized by glucotoxicity and lipotoxicity, the expression profile of mitochondrial carriers is selectively modified. This review describes the role of mitochondrial carriers in beta-cells and the selective changes in response to glucolipotoxicity. In particular, we discuss the importance of the transfer of metabolites (pyruvate, citrate, malate, and glutamate) and nucleotides (ATP, NADH, NADPH) for beta-cell function and dysfunction. This article is part of a Special Issue entitled: Mitochondrial Channels edited by Pierre Sonveaux, Pierre Maechler and Jean-Claude Martinou. PMID:26979549

  8. Human Adipose Stromal Vascular Cell Delivery in a Fibrin Spray

    Science.gov (United States)

    Zimmerlin, Ludovic; Rubin, J. Peter; Pfeifer, Melanie E.; Moore, L.R.; Donnenberg, Vera S.; Donnenberg, Albert D.

    2014-01-01

    Background Adipose tissue represents a practical source of autologous mesenchymal stromal cells (MSC) and vascular-endothelial progenitor cells, available for regenerative therapy without in vitro expansion. One of the problems confronting the therapeutic application of such cells is how to immobilize them at the wound site. Here, we evaluated in vitro the growth and differentiation of human adipose stromal vascular fraction (SVF) cells after delivery using a fibrin spray system. Methods SVF cells were harvested from four human adult patients undergoing elective abdominoplasty using the LipiVage™ system. After collagenase digestion, mesenchymal and endothelial progenitor cells (pericytes, supra-adventitial stromal cells, endothelial progenitors) were quantified by flow cytometry before culture. SVF cells were applied to culture vessels using the Tisseel™ fibrin spray system. SVF cell growth and differentiation was documented by immunofluorescence staining and photomicrography. Results SVF cells remained viable following application and were expanded up to three weeks, when they reached confluence and adipogenic differentiation. Under angiogenic conditions, SVF cells formed endothelial (vWF+, CD31+ and CD34+) tubules surrounded by CD146+ and α-SMA+ perivascular/stromal cells. Discussion Human adipose tissue is a rich source of autologous stem cells, which are readily available for regenerative applications such as wound healing, without in vitro expansion. Our results indicate that mesenchymal and endothelial progenitor cells, prepared in a closed system from unpassaged lipoaspirate samples, retain their growth and differentiation capacity when applied and immobilized on a substrate using a clinically approved fibrin sealant spray system. PMID:23260090

  9. Recombination process in solar cells: Impact on the carrier transport

    Energy Technology Data Exchange (ETDEWEB)

    Gurevich, Yuri G. [Departamento de Fisica, CINVESTAV-IPN, Av. IPN 2508, Apartado Postal 14-740, Mexico D.F. 07000 (Mexico); Velazquez-Perez, Jesus E. [Departamento Fisica Aplicada, Universidad de Salamanca, Plaza de la Merced, 37008 Salamanca (Spain)

    2012-10-15

    Thickness of Si solar cells is being reduced below 200 {mu}m to reduce costs and improve their performance. In conventional solar cells recombination of photo-generated charge carriers plays a major limiting role in the cell efficiency. High quality thin-film solar cells may overcome this limit if the minority diffusion lengths become large as compared to the cell dimensions, but, strikingly, the conventional model fails to describe the cell electric behaviour under these conditions. Moreover, it is shown that in the conventional model the reverse-saturation current diverges (tends to infinity) in thin solar cells. A new formulation of the basic equations describing charge carrier transport in the cell along with a set of boundary conditions is presented. An analytical closed-form solution is obtained under a linear approximation. In the new framework given, the calculation of the open-circuit voltage of the solar cell diode does not lead to unphysical results. (copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  10. Glycoconjugates and Related Molecules in Human Vascular Endothelial Cells

    Directory of Open Access Journals (Sweden)

    Norihiko Sasaki

    2013-01-01

    Full Text Available Vascular endothelial cells (ECs form the inner lining of blood vessels. They are critically involved in many physiological functions, including control of vasomotor tone, blood cell trafficking, hemostatic balance, permeability, proliferation, survival, and immunity. It is considered that impairment of EC functions leads to the development of vascular diseases. The carbohydrate antigens carried by glycoconjugates (e.g., glycoproteins, glycosphingolipids, and proteoglycans mainly present on the cell surface serve not only as marker molecules but also as functional molecules. Recent studies have revealed that the carbohydrate composition of the EC surface is critical for these cells to perform their physiological functions. In this paper, we consider the expression and functional roles of endogenous glycoconjugates and related molecules (galectins and glycan-degrading enzymes in human ECs.

  11. Mitochondrial function in vascular endothelial cell in diabetes

    OpenAIRE

    Pangare, Meenal; Makino, Ayako

    2012-01-01

    Micro- and macrovascular complications are commonly seen in diabetic patients and endothelial dysfunction contributes to the development and progression of the complications. Abnormal functions in endothelial cells lead to the increase in vascular tension and atherosclerosis, followed by systemic hypertension as well as increased incident of ischemia and stroke in diabetic patients. Mitochondria are organelles serving as a source of energy production and as regulators of cell survival (e.g., ...

  12. Cerebro vascular accident in sickle cell disease

    International Nuclear Information System (INIS)

    Sickle cell disease (SCD) is a common inherited hemoglobin disorder characterized by the presence of sickle shaped erythrocytes in the blood. It can cause stroke in around 10% of children. Repeated blood transfusions are often used in an attempt to dilute blood thus reducing the risk of vaso-occlusion and stroke. We report a case of an 11 years old girl, known patient of sickle cell disease, who did not follow regular blood transfusion protocol and as a result presented with recurrent stroke. (author)

  13. Berberine protects vascular endothelial cells in hypertensive rats

    OpenAIRE

    Wang, Yang; Ding, Yun

    2015-01-01

    Objective: This study is to investigate the effect and mechanism of berberine on vascular endothelial cell injury. Methods: The isolated aortic endothelial cells were divided into negative control group, spontaneous hypertension group, and berberine group (1.25, 2.5, and 5 μmol/L berberine). CCK-8 assay was performed to detect cell proliferation. Annexin V-FITC flow cytometry and Hochest33342/PI staining were used to measure cell apoptosis. Expression of TLR4, Myd88, and NF-κB was detected wi...

  14. Vascular potential of human pluripotent stem cells

    Science.gov (United States)

    Cardiovascular disease is the number one cause of death and disability in the US. Understanding the biological activity of stem and progenitor cells, and their ability to contribute to the repair, regeneration and remodeling of the heart and blood vessels affected by pathological processes is an ess...

  15. The control of vascular endothelial cell injury.

    Science.gov (United States)

    Murota, S; Morita, I; Suda, N

    1990-01-01

    The mechanism by which MCI-186 showed a potent cytoprotective effect on the in vitro endothelial cell injury due to 15-HPETE was studied. Stimulation of human leukocytes with various chemical mediators such as TPA, f-Met-Leu-Phe, LTB4, etc. elicited the production of active oxygens, which could be detected by luminol-dependent chemiluminescence. Among the chemical mediators tested, TPA elicited the chemiluminescence the most, and f-Met-Leu-Phe and LTB4 came next. When the leukocytes were directly placed on a monolayer of cultured endothelial cells, followed by stimulating the leukocytes with TPA, severe endothelial cell injury was observed. The effect of TPA was dose dependent. There was good correlation between the active oxygen releasing activity and the cytotoxic activity. When the leukocytes were placed on a filter which was set apart from the monolayer of endothelial cell in a culture dish, and stimulated the leukocytes with TPA, no cytotoxicity was observed. These data strongly suggest that the substance responsible for the cytotoxicity must be a very labile and short-lived substance, presumably active oxygens. On the other hand, MCI-186 was found to have a complete quenching activity to the chemiluminescence due to active oxygens in the TPA-leukocyte system. Taken together, these factors indicate that the potent cytoprotective effect of MCI-186 may be due to its specific radical scavenging activity. PMID:2248437

  16. Human vascular smooth muscle cells express a urate transporter.

    Science.gov (United States)

    Price, Karen L; Sautin, Yuri Y; Long, David A; Zhang, Li; Miyazaki, Hiroki; Mu, Wei; Endou, Hitoshi; Johnson, Richard J

    2006-07-01

    An elevated serum uric acid is associated with the development of hypertension and renal disease. Renal regulation of urate excretion is largely controlled by URAT1 (SLC22A12), a member of the organic anion transporter superfamily. This study reports the specific expression of URAT1 on human aortic vascular smooth muscle cells, as assessed by reverse transcription-PCR and Western blot analysis. Expression of URAT1 was localized to the cell membrane. Evidence that the URAT1 transporter was functional was provided by the finding that uptake of 14C-urate was significantly inhibited in the presence of probenecid, an organic anion transporter inhibitor. It is proposed that URAT1 may provide a mechanism by which uric acid enters the human vascular smooth muscle cell, a finding that may be relevant to the role of uric acid in cardiovascular disease. PMID:16775029

  17. Identification of vascular lineage-specific genes by transcriptional profiling of isolated blood vascular and lymphatic endothelial cells.

    Science.gov (United States)

    Hirakawa, Satoshi; Hong, Young-Kwon; Harvey, Natasha; Schacht, Vivien; Matsuda, Kant; Libermann, Towia; Detmar, Michael

    2003-02-01

    In mammals, the lymphatic vascular system develops by budding of lymphatic progenitor endothelial cells from embryonic veins to form a distinct network of draining vessels with important functions in the immune response and in cancer metastasis. However, the lineage-specific molecular characteristics of blood vascular versus lymphatic endothelium have remained poorly defined. We isolated lymphatic endothelial cells (LECs) and blood vascular endothelial cells (BVECs) by immunomagnetic isolation directly from human skin. Cultured LECs but not BVECs expressed the lymphatic markers Prox1 and LYVE-1 and formed LYVE-1-positive vascular tubes after implantation in vivo. Transcriptional profiling studies revealed increased expression of several extracellular matrix and adhesion molecules in BVECs, including versican, collagens, laminin, and N-cadherin, and of the growth factor receptors endoglin and vascular endothelial growth factor receptor-1/Flt-1. Differential immunostains of human skin confirmed the blood vessel-specific expression of these genes. During embryonic development, endoglin expression was gradually down-regulated on lymphatic endothelium whereas vascular endothelial growth factor receptor-1 was absent from lymphatics. We also identified several genes with specific expression in LECs. These results demonstrate that some lineage-specific genes are only expressed during distinct developmental stages and they identify new molecular markers for blood vascular and lymphatic endothelium with important implications for future studies of vascular development and function. PMID:12547715

  18. Metabolism of bacterial cells bound to solid carriers

    International Nuclear Information System (INIS)

    Escherichia coli 2260 cells bound to solid carriers (iodo-and bromoacetyl cellulose) were incubated in the Davis mineral medium and changes in respiratory activity, ATP level, 14C-valine and 14C-adenine incorporation and the number of bacteria able to multiply were investigated. As compared with suspended cells, no significant changes in the rate and capacity of the metabolic processes studied were recorded. Iodoacetyl cellulose had the smallest effect on the rates of nucleic acids and protein syntheses. (author). 3 figs., 2 tabs., 11 refs

  19. Modulation of Human Vascular Endothelial Cell Behaviors by Nanotopographic Cues

    OpenAIRE

    Liliensiek, S.J.; Wood, J.A.; Yong, J.; Auerbach, R.; Nealey, P.F.; Murphy, C. J.

    2010-01-01

    Basement membranes possess a complex three dimensional topography in the nanoscale and submicron range which have been shown to profoundly modulate a large menu of fundamental cell behaviors. Using the topographic features found in native vascular endothelial basement membranes as a guide, polyurethane substrates were fabricated containing anisotropically ordered ridge and groove structures and isotropically ordered pores from 200 nm to 2000 nm in size. We investigated the impact of biomimeti...

  20. Charge carrier dynamics in thin film solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Strothkaemper, Christian

    2013-06-24

    This work investigates the charge carrier dynamics in three different technological approaches within the class of thin film solar cells: radial heterojunctions, the dye solar cell, and microcrystalline CuInSe{sub 2}, focusing on charge transport and separation at the electrode, and the relaxation of photogenerated charge carriers due to recombination and energy dissipation to the phonon system. This work relies mostly on optical-pump terahertz-probe (OPTP) spectroscopy, followed by transient absorption (TA) and two-photon photoemission (2PPE). The charge separation in ZnO-electrode/In{sub 2}S{sub 3}-absorber core/shell nanorods, which represent a model system of a radial heterojunction, is analyzed by OPTP. It is concluded, that the dynamics in the absorber are determined by multiple trapping, which leads to a dispersive charge transport to the electrode that lasts over hundreds of picoseconds. The high trap density on the order of 10{sup 19}/cm{sup 3} is detrimental for the injection yield, which exhibits a decrease with increasing shell thickness. The heterogeneous electron transfer from a series of model dyes into ZnO proceeds on a time-scale of 200 fs. However, the photoconductivity builds up just on a 2-10 ps timescale, and 2PPE reveals that injected electrons are meanwhile localized spatially and energetically at the interface. It is concluded that the injection proceeds through adsorbate induced interface states. This is an important result because the back reaction from long lived interface states can be expected to be much faster than from bulk states. While the charge transport in stoichiometric CuInSe{sub 2} thin films is indicative of free charge carriers, CuInSe{sub 2} with a solar cell grade composition (Cu-poor) exhibits signs of carrier localization. This detrimental effect is attributed to a high density of charged defects and a high degree of compensation, which together create a spatially fluctuating potential that inhibits charge transport. On

  1. Derived vascular endothelial cells induced by mucoepidermoid carcinoma cells: 3-dimensional collagen matrix model*

    OpenAIRE

    Yang, Sen; Guo, Li-Juan; Gao, Qing-hong; Xuan, Ming; Tan, Ke; Zhang, Qiang; Wen, Yu-ming; Wang, Chang-mei; Tang, Xiu-fa; Wang, Xiao-yi

    2010-01-01

    Mucoepidermoid carcinoma undergoes uniquely vigorous angiogenic and neovascularization processes, possibly due to proliferation of vascular endothelial cells (ECs) induced by mucoepidermoid carcinoma cells (MCCs) in their three-dimensional (3D) microenvironment. To date, no studies have dealt with tumor cells and vascular ECs from the same origin of mucoepidermoid carcinoma using the in vitro 3D microenvironment model. In this context, the current research aims to observe neovascularization w...

  2. Adhesion of bone and vascular cells on a fullerene layer

    Czech Academy of Sciences Publication Activity Database

    Bačáková, Lucie; Grausová, Ľubica; Vacík, Jiří; Jungová, Ivana

    Gyeongju: Korean Carbon Society, 2005. s. 147-147. [Carbon 2005 - International Conference on Carbon. 03.07.2005-07.07.2005, Gyeongju] R&D Projects: GA MŠk(CZ) OC 527.130 Grant ostatní: IGA MŠk(CZ) OC/PR 00680 Institutional research plan: CEZ:AV0Z50110509 Keywords : carbon nanoparticles * nanotechnology * biomaterials * tissue engineering * osteoblast-like MG 63 cells * vascular smooth muscle cells * vinculin * beta-actin Subject RIV: EI - Biotechnology ; Bionics

  3. 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.

  4. Experimental studies of mitochondrial function in CADASIL vascular smooth muscle cells

    International Nuclear Information System (INIS)

    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 (Δψm) 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.

  5. Determination of Orbiter and Carrier Aerodynamic Coefficients from Load Cell Measurements

    Science.gov (United States)

    Glenn, G. M.

    1976-01-01

    A method of determining orbiter and carrier total aerodynamic coefficients from load cell measurements is required to support the inert and the captive active flights of the ALT program. A set of equations expressing the orbiter and carrier total aerodynamic coefficients in terms of the load cell measurements, the sensed dynamics of the Boeing 747 (carrier) aircraft, and the relative geometry of the orbiter/carrier is derived.

  6. Zfp423 promotes adipogenic differentiation of bovine stromal vascular cells.

    Directory of Open Access Journals (Sweden)

    Yan Huang

    Full Text Available Intramuscular fat or marbling is critical for the palatability of beef. In mice, very recent studies show that adipocytes and fibroblasts share a common pool of progenitor cells, with Zinc finger protein 423 (Zfp423 as a key initiator of adipogenic differentiation. To evaluate the role of Zfp423 in intramuscular adipogenesis and marbling in beef cattle, we sampled beef muscle for separation of stromal vascular cells. These cells were immortalized with pCI neo-hEST2 and individual clones were selected by G418. A total of 288 clones (3×96 well plates were isolated and induced to adipogenesis. The presence of adipocytes was assessed by Oil-Red-O staining. Three clones with high and low adipogenic potential respectively were selected for further analyses. In addition, fibro/adipogenic progenitor cells were selected using a surface marker, platelet derived growth factor receptor (PDGFR α. The expression of Zfp423 was much higher (307.4±61.9%, P<0.05 in high adipogenic cells, while transforming growth factor (TGF-β was higher (156.1±48.7%, P<0.05 in low adipogenic cells. Following adipogenic differentiation, the expression of peroxisome proliferator-activated receptor γ (PPARγ and CCAAT/enhancer binding protein α (C/EBPα were much higher (239.4±84.1% and 310.7±138.4%, respectively, P<0.05 in high adipogenic cells. Over-expression of Zfp423 in stromal vascular cells and cloned low adipogenic cells dramatically increased their adipogenic differentiation, accompanied with the inhibition of TGF-β expression. Zfp423 knockdown by shRNA in high adipogenic cells largely prevented their adipogenic differentiation. The differential regulation of Zfp423 and TGF-β between low and high adipogenic cells is associated with the DNA methylation in their promoters. In conclusion, data show that Zfp423 is a critical regulator of adipogenesis in stromal vascular cells of bovine muscle, and Zfp423 may provide a molecular target for enhancing intramuscular

  7. 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.

  8. Nanostructured lipid carriers loaded with resveratrol modulate human dendritic cells

    Science.gov (United States)

    Barbosa, João P; Neves, Ana R; Silva, Andreia M; Barbosa, Mário A; Reis, M Salette; Santos, Susana G

    2016-01-01

    Dendritic cells (DCs) are promising targets for drug delivery, as they can induce immunity or tolerance. The current study aims to examine the potential of using nanostructured lipid carriers (NLC) as delivery systems for human DC by evaluating nanoparticle internalization, cell labeling, and drug activity. NLC were formulated incorporating the fluorochrome fluorescein isothiocyanate (FITC-NLC) or the natural anti-inflammatory molecule resveratrol (rsv-NLC). Primary human DCs were differentiated from peripheral blood monocytes, and the innovative imaging flow cytometry technique was used to examine FITC-NLC internalization. The capacity of rsv-NLC to inhibit DC activation in response to proinflammatory cytokine tumor necrosis factor-α (TNF- α) was investigated by conventional flow cytometry. A combination of imaging and conventional flow cytometry was used to assess NLC cytotoxicity. The results obtained indicate that both NLC formulations were stable over time, with mean diameter nuclear factor κ beta phosphorylation and significantly decrease the level of interleukin-12/23, both upregulated in response to TNF-α, while 10 µM free rsv were needed to promote a similar effect. Taken together, the results presented show that NLC are suitable carriers of fluorescent labels or bioactive molecules for human DCs, leading to inflammation modulation.

  9. From Here to There, Progenitor Cells and Stem Cells Are Everywhere in Lung Vascular Remodeling.

    Science.gov (United States)

    Heise, Rebecca L; Link, Patrick A; Farkas, Laszlo

    2016-01-01

    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 the 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. PMID:27583245

  10. Arteriolar vascular smooth muscle cells: mechanotransducers in a complex environment.

    Science.gov (United States)

    Hill, Michael A; Meininger, Gerald A

    2012-09-01

    Contraction of small artery (diameters typically less than 250 μm) vascular smooth muscle cells (VSMCs) plays a critical role in local control of blood flow and arterial pressure through its affect on vascular caliber. Specifically, contraction of small arteries in response to increased intraluminal pressure is referred to as the myogenic response and represents an important role for mechanotransduction. Critical questions remain as to how changes in pressure are sensed by VSMCs and transduced across the cell membrane to tune the contractile state of the cell. Recent studies suggest a pivotal role for interactions between VSMCs and extracellular matrix (ECM) proteins. Thus, pressure-induced deformation of ECM proteins and their cell surface receptors (for example, integrins) may initiate contraction and cytoskeletal remodeling through modulation of ion channels, membrane depolarization, increased intracellular Ca(2+) and actomyosin crossbridge cycling. Importantly, it is argued that the contractile properties of small artery VSMCs reflect an intimate and integrated interaction with their extracellular environment and the three-dimensional structure of the vessel wall. PMID:22677491

  11. Effect of curcumin on cell cycle progression and apoptosis in vascular smooth muscle cells

    OpenAIRE

    Chen, Huei-Wen; Huang, Huei-Chen

    1998-01-01

    The possible mechanisms of the antiproliferative and apoptotic effects of curcumin (diferuloylmethane), a polyphenol in the spice turmeric, on vascular smooth muscle cells were studied in rat aortic smooth muscle cell line (A7r5).The proliferative response was determined from the uptake of [3H]-thymidine. Curcumin (10−6–10−4 M) inhibited serum-stimulated [3H]-thymidine incorporation of both A7r5 cells and rabbit cultured vascular smooth muscle cells in a concentration-dependent manner. Cell v...

  12. Defining the potential for cell therapy for vascular disease using animal models

    OpenAIRE

    Gulati, Rajiv; Simari, Robert D.

    2009-01-01

    Cell-based therapeutics are currently being developed for a wide array of unmet medical needs. As obstructive vascular disease is the major cause of mortality in the world, cell-based strategies aimed at developing novel therapies or improving current therapies are currently under study. These studies are based on the evolving understanding of the biology of vascular progenitor cells, which has in turn led to the availability of well-defined sources of vascular cells for delivery. Crucial to ...

  13. Generation of vascular endothelial and smooth muscle cells from human pluripotent stem cells

    OpenAIRE

    Patsch, Christoph; Challet-Meylan, Ludivine; Eva C Thoma; Urich, Eduard; Heckel, Tobias; O’Sullivan, John F.; Grainger, Stephanie J.; Kapp, Friedrich G.; Sun, Lin; Christensen, Klaus; Xia, Yulei; Florido, Mary H. C.; He, Wei; Pan, Wei; Prummer, Michael

    2015-01-01

    The use of human pluripotent stem cells for in vitro disease modeling and clinical applications requires protocols that convert these cells into relevant adult cell types. Here, we report the rapid and efficient differentiation of human pluripotent stem cells into vascular endothelial and smooth muscle cells. We found that GSK3 inhibition and BMP4 treatment rapidly committed pluripotent cells to a mesodermal fate and subsequent exposure to VEGF or PDGF-BB resulted in the differentiation of ei...

  14. 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.

  15. Mesenchymal Stem Cells as Immunomodulators in a Vascularized Composite Allotransplantation

    Directory of Open Access Journals (Sweden)

    Yur-Ren Kuo

    2012-01-01

    Full Text Available Vascularized composite allotransplantations (VCAs are not routinely performed for tissue reconstruction because of the potentially harmful adverse effects associated with lifelong administration of immunosuppressive agents. Researchers have been eagerly seeking alternative methods that circumvent the long-term use of immunosuppressants. Mesenchymal stem cells (MSCs show promise as an immunomodulatory therapeutic agent and are currently being tested in preclinical and clinical settings as therapies for autoimmune disorders or transplant rejection. The mechanisms by which MSCs modulate the immune response are still under thorough investigation, but these most likely involve expression of local factors influencing T-cell regulation, modulation of cytokine expression (e.g., IL-10, TGF-β, TNF-, INF-γ, etc., and interactions with dendritic or antigen presenting cells. In this paper, we summarize the current understanding of immunomodulation achieved by MSC therapies and introduce a possible outline for future clinical applications in VCA.

  16. INTERACTIONS BETWEEN THE HUMAN GASTRIC CARCINOMA CELL AND THE HUMAN VASCULAR ENDOTHELIAL CELL

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Objective To definite the interactions between the human gastric carcinoma cell and the human vascular endothelial cell during the establishment and maintenance of the tumor vascular system and the tumor hematogenous metastasis.Methods We prepared the conditioned mediums of each cell so as to study the effect of the conditioned medium on itself or others by MTT colorimetry. The comprehensive effect of interactions between two cells was determined by stratified transfilter co-culture or direct contact co-culture.Results The conditioned medium of human gastric carcinoma cell can stimulate the proliferation of the human vascular endothelial cell, but the CM of HVEC can inhibit the growth of HGCC. Both kinds of cells can inhibit the growth of itself. The ultimate comprehensive effect of the interactions between two kinds of cells was increase of total cell numbers.Conclusion There exist the complicated interactions between the human gastric carcinoma cell and the human vascular endothelial cell during the tumor angiogenesis and the tumor hematogenous metastasis. The ultimate comprehensive effect of the interactions is increase of total cells numbers and tumor volume.

  17. Generation of vascular endothelial and smooth muscle cells from human pluripotent stem cells.

    Science.gov (United States)

    Patsch, Christoph; Challet-Meylan, Ludivine; Thoma, Eva C; Urich, Eduard; Heckel, Tobias; O'Sullivan, John F; Grainger, Stephanie J; Kapp, Friedrich G; Sun, Lin; Christensen, Klaus; Xia, Yulei; Florido, Mary H C; He, Wei; Pan, Wei; Prummer, Michael; Warren, Curtis R; Jakob-Roetne, Roland; Certa, Ulrich; Jagasia, Ravi; Freskgård, Per-Ola; Adatto, Isaac; Kling, Dorothee; Huang, Paul; Zon, Leonard I; Chaikof, Elliot L; Gerszten, Robert E; Graf, Martin; Iacone, Roberto; Cowan, Chad A

    2015-08-01

    The use of human pluripotent stem cells for in vitro disease modelling and clinical applications requires protocols that convert these cells into relevant adult cell types. Here, we report the rapid and efficient differentiation of human pluripotent stem cells into vascular endothelial and smooth muscle cells. We found that GSK3 inhibition and BMP4 treatment rapidly committed pluripotent cells to a mesodermal fate and subsequent exposure to VEGF-A or PDGF-BB resulted in the differentiation of either endothelial or vascular smooth muscle cells, respectively. Both protocols produced mature cells with efficiencies exceeding 80% within six days. On purification to 99% via surface markers, endothelial cells maintained their identity, as assessed by marker gene expression, and showed relevant in vitro and in vivo functionality. Global transcriptional and metabolomic analyses confirmed that the cells closely resembled their in vivo counterparts. Our results suggest that these cells could be used to faithfully model human disease. PMID:26214132

  18. Vascular smooth muscle cell differentiation from human stem/progenitor cells.

    Science.gov (United States)

    Steinbach, Sarah K; Husain, Mansoor

    2016-05-15

    Transplantation of vascular smooth muscle cells (VSMCs) is a promising cellular therapy to promote angiogenesis and wound healing. However, VSMCs are derived from diverse embryonic sources which may influence their role in the development of vascular disease and in its therapeutic modulation. Despite progress in understanding the mechanisms of VSMC differentiation, there remains a shortage of robust methods for generating lineage-specific VSMCs from pluripotent and adult stem/progenitor cells in serum-free conditions. Here we describe a method for differentiating pluripotent stem cells, such as embryonic and induced pluripotent stem cells, as well as skin-derived precursors, into lateral plate-derived VSMCs including 'coronary-like' VSMCs and neural crest-derived VSMC, respectively. We believe this approach will have broad applications in modeling origin-specific disease vulnerability and in developing personalized cell-based vascular grafts for regenerative medicine. PMID:26678794

  19. Carrier injection dynamics in heterojunction solar cells with bipolar molecule

    Energy Technology Data Exchange (ETDEWEB)

    Takahashi, Yosuke; Yonezawa, Kouhei [Graduate School of Pure and Applied Science, University of Tsukuba, Tsukuba 305-8571 (Japan); Yasuda, Takeshi, E-mail: YASUDA.Takeshi@nims.go.jp, E-mail: moritomo.yutaka.gf@u.tsukuba.ac.jp [Photovoltaic Materials Unit, National Institute for Materials Science (NIMS), Tsukuba 305-0047 (Japan); Moritomo, Yutaka, E-mail: YASUDA.Takeshi@nims.go.jp, E-mail: moritomo.yutaka.gf@u.tsukuba.ac.jp [Graduate School of Pure and Applied Science, University of Tsukuba, Tsukuba 305-8571 (Japan); Center for Integrated Research in Fundamental Science and Engineering (CiRfSE), University of Tsukuba, Tsukuba 305-8571 (Japan)

    2015-03-23

    A boron subphthalocyanine chloride (SubPc) is a bipolar molecule and is used in hetero-junction organic solar cells. Here, we investigated the carrier injection dynamics from the donor α-sexithiophene (6T) or acceptor C{sub 60} layers to the bipolar SubPc layer by means of the femtosecond time-resolved spectroscopy. We observed gradual increase of the SubPc{sup –} (SubPc{sup +}) species within ≈300 ps. The increases are interpreted in terms of the exciton diffusion within the 6T (C{sub 60}) layer and subsequent electron (hole) injection at the interface. In 6T/SubPc heterojunction, the electron injection is observed even at 80 K. The robust electron injection is ascribed to the efficient charge separation within the 6T layer under photo exciation at 400 nm.

  20. Carrier injection dynamics in heterojunction solar cells with bipolar molecule

    International Nuclear Information System (INIS)

    A boron subphthalocyanine chloride (SubPc) is a bipolar molecule and is used in hetero-junction organic solar cells. Here, we investigated the carrier injection dynamics from the donor α-sexithiophene (6T) or acceptor C60 layers to the bipolar SubPc layer by means of the femtosecond time-resolved spectroscopy. We observed gradual increase of the SubPc– (SubPc+) species within ≈300 ps. The increases are interpreted in terms of the exciton diffusion within the 6T (C60) layer and subsequent electron (hole) injection at the interface. In 6T/SubPc heterojunction, the electron injection is observed even at 80 K. The robust electron injection is ascribed to the efficient charge separation within the 6T layer under photo exciation at 400 nm

  1. Embryonic origins of human vascular smooth muscle cells: implications for in vitro modeling and clinical application

    OpenAIRE

    Sinha, Sanjay; Iyer, Dharini; Granata, Alessandra

    2014-01-01

    Vascular smooth muscle cells (SMCs) arise from multiple origins during development, raising the possibility that differences in embryological origins between SMCs could contribute to site-specific localization of vascular diseases. In this review, we first examine the developmental pathways and embryological origins of vascular SMCs and then discuss in vitro strategies for deriving SMCs from human embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs). We then review in detail...

  2. Impact of intense pulsed light irradiation on cultured primary fibroblasts and a vascular endothelial cell line

    OpenAIRE

    Wu, Di; Zhou, BingRong; Xu, Yang; Yin, Zhiqiang; Luo, Dan

    2012-01-01

    The aim of this study was to determine the effects of intense pulsed light (IPL) on cell proliferation and the secretion of vascular endothelial growth factor (VEGF) and matrix metalloproteinases (MMPs) in human fibroblasts and vascular endothelial cell lines, and to investigate the effects of IPL on the mRNA expression levels of type I and III procollagens in cultured human fibroblasts. Foreskin fibroblasts and a vascular endothelial cell line (ECV034) were cultured and treated with various ...

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

    OpenAIRE

    Wu, Junxi; Hadoke, Patrick W.F.; Takov, Kaloyan; Korczak, Agnieszka; Denvir, Martin A.; Smith, Lee B.

    2016-01-01

    Aims 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. Methods and Results Mice with selective deletion of AR (ARKO) from vascular smooth muscle cells (SM-ARKO), endoth...

  4. Activated vascular endothelia regulate invasion of glioma cells through expression of fibronectin

    Institute of Scientific and Technical Information of China (English)

    LIN Zhi-xiong; YANG Li-juan; HUANG Qiang; FU Jin

    2010-01-01

    Background Previous researches have indicated that glioma invasion may occur within a tumor-host microecology, and that fibronectin may be involved in glioma invasion as an important component of the extracellular matrix. However, how the interaction between tumor cells and vascular endothelial cells affects glioma invasion is poorly understood. The aim of this study was to investigate the effects of the interaction between tumor cells and vascular endothelial cells on glioma invasion, and the relationship of this interaction to fibronectin.Methods The localization of fibronectin in different brain astrocytoma tissues was determined by immunohistochemistry. Then, vascular endothelial cells and glioma cells were co-cultured in a Transwell co-culturing system. Fibronectin expression was detected by reverse transcriptase-polymerase chain reaction, immunocytochemistry, and enzyme-linked immunosorbent assay. Additionally, the influence of the interaction between tumor cells and vascular endothelial cells on glioma cell invasion was determined by an in vitro rapid invasion test.Results In brain astrocytoma tissues, fibronectin was present on the endothelial cells, in the extracellular matrix. Fibronectin expression was greater in higher grade tumors than in lower grade tumors. The interaction of glioma cells and vascular endothelial cells in vitro induced fibronectin release from vascular endothelial cells, which in turn stimulated glioma cell migration. This effect was inhibited by fibronectin blocking antibody.Conclusion Glioma cells may induce vascular epithelial cells to express fibronectin, and in turn fibronectin could promote glioma cell invasion.

  5. 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...... levels of VCAM-1, but not E-selectin, were significantly lower in GHD patients than in healthy subjects (362 +/- 15 microg/liter vs. 516 +/- 21 microg/liter, P < 0.001) and increased in GHD patients during GH treatment, compared with placebo [net difference between groups 151.8 microg/liter (95...

  6. Simulated Hypergravity Alters Vascular Smooth Muscle Cell Proliferation and Motility

    Science.gov (United States)

    Hunt, Shameka; Bettis, Barika; Harris-Hooker, Sandra; Sanford, Gary L.

    1997-01-01

    The cellular effects of gravity are poorly understood due to its constancy and nonavailability of altered gravitational models. Such an understanding is crucial for prolonged space flights. In these studies, we assessed the influence of centrifugation at 6G (HGrav) on vascular smooth muscle (SMC) mobility and proliferation. Cells were: (a) plated at low density and subjected to HGrav for 24-72 hr for proliferation studies, or (b) grown to confluency, subjected to HGrav, mechanically denuded and monitored for cell movement into the denuded area. Controls were maintained under normogravity. SMC showed a 50% inhibition of growth under HGrav and 10% serum; HGrav and low serum resulted in greater growth inhibition. The rate of movement of SMC into the denuded area was 2-3-fold higher under HGrav in low serum compared to controls, but similar in 10% serum. These studies show that HGrav has significant effects on SMC growth and mobility, which are dependent on serum levels.

  7. Process optimization and biocompatibility of cell carriers suitable for automated magnetic manipulation.

    OpenAIRE

    Krejci, I; Piana, C.; Howitz, S.; Wegener, T; Fiedler, S.; ZWANZIG, M.; Schmitt, D.; Daum, N; Meier, K.; Lehr, C. M.; Batista, U; Zemljic, S; Messerschmidt, J.; Franzke, J; M. Wirth

    2012-01-01

    There is increasing demand for automated cell reprogramming in the fields of cell biology, biotechnology and the biomedical sciences. Microfluidic-based platforms that provide unattended manipulation of adherent cells promise to be an appropriate basis for cell manipulation. In this study we developed a magnetically driven cell carrier to serve as a vehicle within an in vitro environment. To elucidate the impact of the carrier on cells, biocompatibility was estimated using the human adenocarc...

  8. Regulation of cyclooxygenase expression in cultured vascular cells

    International Nuclear Information System (INIS)

    Arachidonic acid metabolism in vascular tissue results in synthesis of prostacylin. The key enzyme in this synthesis pathway, cyclooxygenase, is down-regulated through self-inactivation. An analogous refractory state is produced by aspirin which irreversibly acetylates the enzyme. To further understand this phenomenon, the inactivation and recovery of cyclooxygenase activity was assayed in cultured ray vascular smooth muscle cells using exogenously added arachidonic acid. Self-inactivation of cyclooxygenase was observed following treatment with micromolar amounts of arachidonic acid. The recovery of cyclooxygenase activity following self-inactivation was analogous to that observed following aspirin-inactivation in that it depended on protein synthesis and required either serum or EGF. Two additional factors, TGF-β and uric acid, were found to enhance the stimulation of cyclooxygenase recovery by EGF. A defined medium containing 10 ng/mL EGF, 1 ng/mL TGFβ and 0.1 mM uric acid duplicated the cyclooxygenase recovery activity of 10% serum. Stimulation of cyclooxygenase activity by EGF and TGF-β was inhibited by cycloheximide but not by actinomycin-D, indicating a link to increased translation of pre-existing mRNA. A lack of significant effect on overall protein synthesis by EGF and TGF-β, measured by [35S]-methionine incorporation under conditions where a multi-fold increase in cyclooxygenase activity was seen, indicates that the translational regulation of a small fraction of total mRNA and possibly cyclooxygenase is occurring

  9. Modeling human endothelial cell transformation in vascular neoplasias

    Directory of Open Access Journals (Sweden)

    Victoria W. Wen

    2013-09-01

    Full Text Available Endothelial cell (EC-derived neoplasias range from benign hemangioma to aggressive metastatic angiosarcoma, which responds poorly to current treatments and has a very high mortality rate. The development of treatments that are more effective for these disorders will be expedited by insight into the processes that promote abnormal proliferation and malignant transformation of human ECs. The study of primary endothelial malignancy has been limited by the rarity of the disease; however, there is potential for carefully characterized EC lines and animal models to play a central role in the discovery, development and testing of molecular targeted therapies for vascular neoplasias. This review describes molecular alterations that have been identified in EC-derived neoplasias, as well as the processes that underpin the immortalization and tumorigenic conversion of ECs. Human EC lines, established through the introduction of defined genetic elements or by culture of primary tumor tissue, are catalogued and discussed in relation to their relevance as models of vascular neoplasia.

  10. Oxidative stress modulates PPAR gamma in vascular endothelial cells.

    Science.gov (United States)

    Blanquicett, Carmelo; Kang, Bum-Yong; Ritzenthaler, Jeffrey D; Jones, Dean P; Hart, C Michael

    2010-06-15

    The peroxisome proliferator-activated receptor gamma (PPAR gamma) plays an important role in vascular regulation. However, the impact of oxidative stress on PPAR gamma expression and activity has not been clearly defined. Human umbilical vein endothelial cells (HUVECs) were exposed to graded concentrations of H(2)O(2) for 0.5-72h, or bovine aortic endothelial cells (BAECs) were exposed to alterations in extracellular thiol/disulfide redox potential (E(h)) of the cysteine/cystine couple. Within 2h, H(2)O(2) reduced HUVEC PPAR gamma mRNA and activity and reduced the expression of two PPAR gamma-regulated genes without altering PPAR gamma protein levels. After 4h H(2)O(2) exposure, mRNA levels remained reduced, whereas PPAR gamma activity returned to control levels. PPAR gamma mRNA levels remained depressed for up to 72 h after exposure to H(2)O(2), without any change in PPAR gamma activity. Catalase prevented H(2)O(2)-induced reductions in PPAR gamma mRNA and activity. H(2)O(2) (1) reduced luciferase expression in HUVECs transiently transfected with a human PPAR gamma promoter reporter, (2) failed to alter PPAR gamma mRNA half-life, and (3) transiently increased expression and activity of c-Fos and phospho-c-Jun. Treatment with the AP1 inhibitor curcumin prevented H(2)O(2)-mediated reductions in PPAR gamma expression. In addition, medium having an oxidized E(h) reduced BAEC PPAR gamma mRNA and activity. These findings demonstrate that oxidative stress, potentially through activation of inhibitory redox-regulated transcription factors, attenuates PPAR gamma expression and activity in vascular endothelial cells through suppression of PPAR gamma transcription. PMID:20302927

  11. Polyacylurethanes as Novel Degradable Cell Carrier Materials for Tissue Engineering

    Directory of Open Access Journals (Sweden)

    Arend Jan Schouten

    2011-10-01

    Full Text Available Polycaprolactone (PCL polyester and segmented aliphatic polyester urethanes based on PCL soft segment have been thoroughly investigated as biodegradable scaffolds for tissue engineering. Although proven beneficial as long term implants, these materials degrade very slowly and are therefore not suitable in applications in which scaffold support is needed for a shorter time. A recently developed class of polyacylurethanes (PAUs is expected to fulfill such requirements. Our aim was to assess in vitro the degradation of PAUs and evaluate their suitability as temporary scaffold materials to support soft tissue repair. With both a mass loss of 2.5–3.0% and a decrease in molar mass of approx. 35% over a period of 80 days, PAUs were shown to degrade via both bulk and surface erosion mechanisms. Fourier Transform Infra Red (FTIR spectroscopy was successfully applied to study the extent of PAUs microphase separation during in vitro degradation. The microphase separated morphology of PAU1000 (molar mass of the oligocaprolactone soft segment = 1000 g/mol provided this polymer with mechano-physical characteristics that would render it a suitable material for constructs and devices. PAU1000 exhibited excellent haemocompatibility in vitro. In addition, PAU1000 supported both adhesion and proliferation of vascular endothelial cells and this could be further enhanced by pre-coating of PAU1000 with fibronectin (Fn. The contact angle of PAU1000 decreased both with in vitro degradation and by incubation in biological fluids. In endothelial cell culture medium the contact angle reached 60°, which is optimal for cell adhesion. Taken together, these results support the application of PAU1000 in the field of soft tissue repair as a temporary degradable scaffold.

  12. Inflammation, glucose, and vascular cell damage: the role of the pentose phosphate pathway

    OpenAIRE

    Peiró, Concepción; Romacho, Tania; Azcutia, Verónica; Villalobos, Laura; Fernández, Emilio; Bolaños, Juan P.; Moncada, Salvador; Sánchez-Ferrer, Carlos F

    2016-01-01

    Background Hyperglycemia is acknowledged as a pro-inflammatory condition and a major cause of vascular damage. Nevertheless, we have previously described that high glucose only promotes inflammation in human vascular cells previously primed with pro-inflammatory stimuli, such as the cytokine interleukin (IL)1β. Here, we aimed to identify the cellular mechanisms by which high glucose exacerbates the vascular inflammation induced by IL1β. Methods Cultured human aortic smooth muscle cells (HASMC...

  13. Virulent Treponema pallidum activates human vascular endothelial cells.

    Science.gov (United States)

    Riley, B S; Oppenheimer-Marks, N; Hansen, E J; Radolf, J D; Norgard, M V

    1992-03-01

    Perivascular lymphocytic infiltration, fibrin deposition, and endothelial cell abnormalities consistent with cellular activation are prominent histopathologic features of syphilis, a sexually transmitted disease caused by the spirochetal bacterium Treponema pallidum. Because activated endothelial cells play important roles in lymphocyte homing and hemostasis, the ability of virulent T. pallidum to activate cultured human umbilical vein endothelial cells (HUVEC) was investigated. T. pallidum induced the expression of intercellular adhesion molecule-1 (ICAM-1) and procoagulant activity on the surface of HUVEC. Electron microscopy of T. pallidum-stimulated HUVEC revealed extensive networks of fibrin strands not observed in cultures without treponemes. ICAM-1 expression in HUVEC also was promoted by a 47-kDa integral membrane lipoprotein purified from T. pallidum, implicating a role for spirochete membrane lipoproteins in endothelial cell activation. The combined findings are consistent with the pathology of syphilis and provide the first evidence that a pathogenic spirochetal bacterium such as T. pallidum or its constituent integral membrane lipoprotein(s) can activate directly host vascular endothelium. PMID:1347056

  14. Extracellular calcium sensing in rat aortic vascular smooth muscle cells

    International Nuclear Information System (INIS)

    Extracellular calcium (Ca2+o) can act as a first messenger in many cell types through a G protein-coupled receptor, calcium-sensing receptor (CaR). It is still debated whether the CaR is expressed in vascular smooth muscle cells (VSMCs). Here, we report the expression of CaR mRNA and protein in rat aortic VSMCs and show that Ca2+o stimulates proliferation of the cells. The effects of Ca2+o were attenuated by pre-treatment with MAPK kinase 1 (MEK1) inhibitor, as well as an allosteric modulator, NPS 2390. Furthermore, stimulation of the VSMCs with Ca2+o-induced phosphorylation of ERK1/2, but surprisingly did not cause inositol phosphate accumulation. We were not able to conclusively state that the CaR mediates Ca2+o-induced cell proliferation. Rather, an additional calcium-sensing mechanism may exist. Our findings may be of importance with regard to atherosclerosis, an inflammatory disease characterized by abnormal proliferation of VSMCs and high local levels of calcium

  15. The Use of Fiber-Reinforced Scaffolds Cocultured with Schwann Cells and Vascular Endothelial Cells to Repair Rabbit Sciatic Nerve Defect with Vascularization

    OpenAIRE

    Hongyang Gao; Yang You; Guoping Zhang; Feng Zhao; Ziyi Sha; Yong Shen

    2013-01-01

    To explore the feasibility of biodegradable fiber-reinforced 3D scaffolds with satisfactory mechanical properties for the repair of long-distance sciatic nerve defect in rabbits and effects of vascularized graft in early stage on the recovery of neurological function, Schwann cells and vascular endothelial cells were cocultured in the fiber-reinforced 3D scaffolds. Experiment group which used prevascularized nerve complex for the repair of sciatic nerve defect and control group which only cul...

  16. Intracellular pathways of insulin transport across vascular endothelial cells

    International Nuclear Information System (INIS)

    Processing and transport of hormones across vascular endothelial cells may modulate hormone action at subendothelial tissue sites. Insulin was transported across cultured rat capillary and bovine aortic endothelial cells, after a delay of 5-10 min, at a constant rate for 60 min at 37 degrees C. 125I-labeled insulin transport was inhibited by 88 +/- 11% (SE, n = 4) and 75 +/- 18% (SE, n = 4) in the presence of anti-insulin receptor antibody and unlabeled insulin (at 10(-7) M), respectively. Reverse phase high-performance liquid chromatography showed 88% of the 125I-insulin transported over 60 min was indistinguishable from the 125I-insulin added to the cells at 4 degrees C. In aortic endothelial cells preincubated with 2.3 x 10(-9) M of insulin for 24 h, insulin receptor binding was downregulated by 67%, and 125I-insulin transport was decreased by 52 +/- 11%. The proton ionophore monensin (0.05 mM) increased the internalized insulin in bovine aortic endothelial cells by 78%, with a corresponding decrease in 125I-insulin released by 76 +/- 2% (SE, n = 4). 125I-insulin transport across the aortic endothelial cell monolayer was similarly decreased (54 +/- 12%, SE, n = 4) by monensin. In contrast, the lysosomal protease inhibitor leupeptin had no effect. Degradation and transport were similarly dissociated by low temperature. At 15 degrees C, no significant insulin degradation was detected, whereas 125I-insulin release from the cells continued at 30 +/- 3% of the rate at 37 degrees C

  17. 3D Reconstruction of Coronary Artery Vascular Smooth Muscle Cells.

    Directory of Open Access Journals (Sweden)

    Tong Luo

    Full Text Available The 3D geometry of individual vascular smooth muscle cells (VSMCs, which are essential for understanding the mechanical function of blood vessels, are currently not available. This paper introduces a new 3D segmentation algorithm to determine VSMC morphology and orientation.A total of 112 VSMCs from six porcine coronary arteries were used in the analysis. A 3D semi-automatic segmentation method was developed to reconstruct individual VSMCs from cell clumps as well as to extract the 3D geometry of VSMCs. A new edge blocking model was introduced to recognize cell boundary while an edge growing was developed for optimal interpolation and edge verification. The proposed methods were designed based on Region of Interest (ROI selected by user and interactive responses of limited key edges. Enhanced cell boundary features were used to construct the cell's initial boundary for further edge growing. A unified framework of morphological parameters (dimensions and orientations was proposed for the 3D volume data. Virtual phantom was designed to validate the tilt angle measurements, while other parameters extracted from 3D segmentations were compared with manual measurements to assess the accuracy of the algorithm. The length, width and thickness of VSMCs were 62.9±14.9 μm, 4.6±0.6 μm and 6.2±1.8 μm (mean±SD. In longitudinal-circumferential plane of blood vessel, VSMCs align off the circumferential direction with two mean angles of -19.4±9.3° and 10.9±4.7°, while an out-of-plane angle (i.e., radial tilt angle was found to be 8±7.6° with median as 5.7°.A 3D segmentation algorithm was developed to reconstruct individual VSMCs of blood vessel walls based on optical image stacks. The results were validated by a virtual phantom and manual measurement. The obtained 3D geometries can be utilized in mathematical models and leads a better understanding of vascular mechanical properties and function.

  18. Study on the biological characteristics of pancreatic cancer vascular endothelial cells

    Institute of Scientific and Technical Information of China (English)

    李雷

    2012-01-01

    Objective To explore the biological characteristics of pancreatic cancer vascular endothelial cells,including the aspects of morphology,species,genetics,vascular formation ability,and proliferation ability in vitro. Methods The human pancreatic cancer cells were inoculated in nude mice pancreas to get pancreatic cancer

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

    Directory of Open Access Journals (Sweden)

    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.

  20. D609 induces vascular endothelial cells and marrow stromal cells differentiation into neuron-like cells

    Institute of Scientific and Technical Information of China (English)

    Nan WANG; Chun-qing DU; Shao-shan WANG; Kun XIE; Shang-li ZHANG; Jun-ying MIAO

    2004-01-01

    AIM: To investigate the effect of tricyclodecane-9-yl-xanthogenate (D609) on cell differentiation in vascular endothelial cells (VECs) and marrow stromal cells (MSCs). METHODS: Morphological changes were observed under phase contrast microscope. Electron microscope and immunostaining were used for VECs identification. The expressions of neuron-specific enolase (NSE) and glial fibrillary acidic protein (GFAP) were examined by immunohistochemistry. RESULTS: After 6 h of induction with D609, some VECs showed morphological changes characteristic of neurones. 9 h later, more VECs became neuron-like cells. About 30.8 % of VECs displayed positive NSE (P<0.01), while the expression of GFAP was negative. When MSCs were exposed to D609, the cells displayed neuronal morphologies, such as pyramidal cell bodies and processes formed extensive networks at 3 h. 6 h later, almost all of the cells exhibited a typical neuronal appearance, and 85.6 % of MSCs displayed intensive positive NSE, but GFAP did not express. CONCLUSION: D609 induces VECs and MSCs differentiation into neuron-like cells.

  1. The adhesion receptor CD44 promotes atherosclerosis by mediating inflammatory cell recruitment and vascular cell activation

    Science.gov (United States)

    Cuff, Carolyn A.; Kothapalli, Devashish; Azonobi, Ijeoma; Chun, Sam; Zhang, Yuanming; Belkin, Richard; Yeh, Christine; Secreto, Anthony; Assoian, Richard K.; Rader, Daniel J.; Puré, Ellen

    2001-01-01

    Atherosclerosis causes most acute coronary syndromes and strokes. The pathogenesis of atherosclerosis includes recruitment of inflammatory cells to the vessel wall and activation of vascular cells. CD44 is an adhesion protein expressed on inflammatory and vascular cells. CD44 supports the adhesion of activated lymphocytes to endothelium and smooth muscle cells. Furthermore, ligation of CD44 induces activation of both inflammatory and vascular cells. To assess the potential contribution of CD44 to atherosclerosis, we bred CD44-null mice to atherosclerosis-prone apoE-deficient mice. We found a 50–70% reduction in aortic lesions in CD44-null mice compared with CD44 heterozygote and wild-type littermates. We demonstrate that CD44 promotes the recruitment of macrophages to atherosclerotic lesions. Furthermore, we show that CD44 is required for phenotypic dedifferentiation of medial smooth muscle cells to the “synthetic” state as measured by expression of VCAM-1. Finally, we demonstrate that hyaluronan, the principal ligand for CD44, is upregulated in atherosclerotic lesions of apoE-deficient mice and that the low-molecular-weight proinflammatory forms of hyaluronan stimulate VCAM-1 expression and proliferation of cultured primary aortic smooth muscle cells, whereas high-molecular-weight forms of hyaluronan inhibit smooth muscle cell proliferation. We conclude that CD44 plays a critical role in the progression of atherosclerosis through multiple mechanisms. PMID:11581304

  2. Bile acids increase intracellular Ca2+ concentration and nitric oxide production in vascular endothelial cells

    OpenAIRE

    Nakajima, Toshiaki; Okuda, Yukichi; Chisaki, Keigo; Shin, Wee-Soo; Iwasawa, Kuniaki; Morita, Toshihiro; Matsumoto, Akihiro; Suzuki, Jun-ichi; Suzuki, Seizi; Yamada, Nobuhiro; Toyo-Oka, Teruhiko; Nagai, Ryozo; Omata, Masao

    2000-01-01

    The effects of bile acids on intracellular Ca2+ concentration [Ca2+]i and nitric oxide production were investigated in vascular endothelial cells.Whole-cell patch clamp techniques and fluorescence measurements of [Ca2+]i were applied in vascular endothelial cells obtained from human umbilical and calf aortic endothelial cells. Nitric oxide released was determined by measuring the concentration of NO2−.Deoxycholic acid, chenodeoxycholic acid and the taurine conjugates increased [Ca2+]i concent...

  3. Apoptosis in vascular cells induced by cold atmospheric plasma treatment

    Science.gov (United States)

    Sladek, Raymond; Stoffels, Eva

    2006-10-01

    Apoptosis is a natural mechanism of cellular self-destruction. It can be triggered by moderate, yet irreversible damage. Apoptosis plays a major role in tissue renewal. Artificial apoptosis induction will become a novel therapy that meets all requirements for tissue-saving surgery. Diseased tissues can disappear without inflammation and scarring. This is particularly important in treatment of blockages in body tracts (e.g. cardiovascular diseases). Artificial induction of apoptosis can be achieved by means of cold plasma treatment. In this work an atmospheric micro-plasma operated in helium/air has been used to induce apoptosis in vascular cells. Parametric studies of apoptosis induction have been conducted; the efficiency is almost 100%. The apoptotic factors are ROS/RNS (reactive oxygen and nitrogen species). Their densities in the plasma have been measured by mass spectrometry. For apoptosis induction, RNS seem to be more important than ROS, because of their relative abundance. Moreover, addition of a ROS scavenger (ascorbic acid) to the cell culture medium does not reduce the occurrence of apoptosis. Cold plasma is a very efficient tool for fundamental studies of apoptosis, and later, for controlled tissue removal in vivo.

  4. Endothelial progenitor cell recruitment in a microfluidic vascular model.

    Science.gov (United States)

    Lewis, Daniel M; Abaci, Hasan E; Xu, Yu; Gerecht, Sharon

    2015-12-01

    During vessel injury, endothelial progenitors cells (EPCs) are recruited from bone marrow and directed to the hypoxic injury site. The hypoxic conditions in the damaged blood vessel promote TNF-α, which upregulates intercellular adhesion molecule-1 (ICAM-1). EPCs attach to endothelial cell lining using ICAM-1. Here we aimed to examine EPC attachment to ECs in an injured-blood vessel conditions. We first determined ICAM-1 expression in stimulated HUVECs. We stimulated HUVECs with 21% oxygen (atmospheric), atmospheric with TNF-α-supplemented media, 1% oxygen (hypoxia), and hypoxia with TNF-α-supplemented media and found the highest ECFC attachment on HUVECs stimulated with TNF-α and hypoxia, correlating with the highest ICAM-1 expression. We next designed, fabricated and tested a three-dimensional microbioreactor (3D MBR) system with precise control and monitoring of dissolve oxygen and media flow rate in the cellular environment. We utilized a step-wise seeding approach, producing monolayer of HUVECs on all four walls. When stimulated with both TNF-α and hypoxia, ECFC retention on HUVECs was significantly increased under low shear stress compared to static controls. Overall, the 3D MBR system mimics the pathological oxygen tension and shear stress in the damaged vasculature, providing a platform to model vascular-related disorders. PMID:26693599

  5. Targeted delivery of microRNA-126 to vascular endothelial cells via REDV peptide modified PEG-trimethyl chitosan.

    Science.gov (United States)

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

    2016-05-26

    Manipulation of gene expression by means of microRNAs (miRNAs) is one of the emerging strategies to treat cardiovascular and cancer diseases. Nevertheless, efficient delivery of miRNAs to a specific vascular tissue is limited. In this work, a short peptide Arg-Glu-Asp-Val (REDV) was linked to trimethyl chitosan (TMC) via a bifunctional poly(ethylene glycol) (PEG) linker for the targeted delivery of microRNA-126 (miRNA-126) to vascular endothelial cells (VECs). The morphology, serum stability and cytotoxicity of the polyplex/miRNA complexes, namely, TMC/miRNA, TMC-g-PEG/miRNA and TMC-g-PEG-REDV/miRNA, were investigated along with the cellular uptake, proliferation and in vitro miRNA transfection efficiency. By REDV modification, the TMC-g-PEG-REDV/miRNA complex showed negligible cytotoxicity, increased expression of miRNA-126 and enhanced VEC proliferation compared with the TMC/miRNA and TMC-g-PEG/miRNA complexes. In particular, the approaches adopted for the miRNA delivery and targeted peptide REDV modification promote the selective uptake and the growth of VECs over vascular smooth muscle cells. It was suggested that the REDV peptide-modified TMC-g-PEG polyplex could be potentially used as a miRNA carrier in artificial blood vessels for rapid endothelialization. PMID:27055482

  6. Study on immobilized yeast cells with hydrophilic polymer carrier by radiation-induced copolymerization

    International Nuclear Information System (INIS)

    Various kinds of monomers 2-hydroxyethyl methacrylate (HEMA), 2-hydroxyethyl acrylate (HEA), hydroxypropyl methacrylate (HPMA) and methoxy polyethylene glycol methylacrylate (M-23G) are copolymerized by radiation technique at low temperature (-78 degree C) and several kinds of copolymer carriers were obtained. Yeast cells are immobilized through adhesion and multiplication of yeast cells themselves on these carriers. The ethanol productivity of immobilized yeast cells with these carriers was related to the monomer composition and water content of copolymer carriers and the optimum monomer composition was 20%:10% in poly (HEA-M23G). In this case, the ethanol productivity of immobilized yeast cells was 26 mg/(ml · h), which was 4 times as high as that of free cells. Effect of adding crosslinking reagent (4G) in lower monomer composition of poly(HEA-M23G) on the ethanol productivity of immobilized cells was better than that in higher one in this work

  7. Reversible electron-hole separation in a hot carrier solar cell

    OpenAIRE

    Limpert, Steven; Bremner, Stephen; Linke, Heiner

    2015-01-01

    Hot-carrier solar cells are envisioned to utilize energy filtering to extract power from photogenerated electron-hole pairs before they thermalize with the lattice, and thus potentially offer higher power conversion efficiency compared to conventional, single absorber solar cells. The efficiency of hot-carrier solar cells can be expected to strongly depend on the details of the energy filtering process, a relationship which to date has not been satisfactorily explored. Here, we establish the ...

  8. Reactive oxygen species and angiotensin II signaling in vascular cells: implications in cardiovascular disease

    Directory of Open Access Journals (Sweden)

    Touyz R.M.

    2004-01-01

    Full Text Available Diseases such as hypertension, atherosclerosis, hyperlipidemia, and diabetes are associated with vascular functional and structural changes including endothelial dysfunction, altered contractility and vascular remodeling. Cellular events underlying these processes involve changes in vascular smooth muscle cell (VSMC growth, apoptosis/anoikis, cell migration, inflammation, and fibrosis. Many factors influence cellular changes, of which angiotensin II (Ang II appears to be amongst the most important. The physiological and pathophysiological actions of Ang II are mediated primarily via the Ang II type 1 receptor. Growing evidence indicates that Ang II induces its pleiotropic vascular effects through NADPH-driven generation of reactive oxygen species (ROS. ROS function as important intracellular and intercellular second messengers to modulate many downstream signaling molecules, such as protein tyrosine phosphatases, protein tyrosine kinases, transcription factors, mitogen-activated protein kinases, and ion channels. Induction of these signaling cascades leads to VSMC growth and migration, regulation of endothelial function, expression of pro-inflammatory mediators, and modification of extracellular matrix. In addition, ROS increase intracellular free Ca2+ concentration ([Ca2+]i, a major determinant of vascular reactivity. ROS influence signaling molecules by altering the intracellular redox state and by oxidative modification of proteins. In physiological conditions, these events play an important role in maintaining vascular function and integrity. Under pathological conditions ROS contribute to vascular dysfunction and remodeling through oxidative damage. The present review focuses on the biology of ROS in Ang II signaling in vascular cells and discusses how oxidative stress contributes to vascular damage in cardiovascular disease.

  9. In vivo imaging of tumor vascular endothelial cells

    Science.gov (United States)

    Zhao, Dawen; Stafford, Jason H.; Zhou, Heling; Thorpe, Philip E.

    2013-02-01

    Phosphatidylserine (PS), normally restricted to the inner leaflet of the plasma membrane, becomes exposed on the outer surface of viable (non-apoptotic) endothelial cells in tumor blood vessels, probably in response to oxidative stresses present in the tumor microenvironment. In the present study, we optically imaged exposed PS on tumor vasculature in vivo using PGN635, a novel human monoclonal antibody that targets PS. PGN635 F(ab')2 was labeled with the near infrared (NIR) dye, IRDye 800CW. Human glioma U87 cells or breast cancer MDA-MB-231 cells were implanted subcutaneously or orthotopically into nude mice. When the tumors reached ~5 mm in diameter, 800CW- PGN635 was injected via a tail vein and in vivo dynamic NIR imaging was performed. For U87 gliomas, NIR imaging allowed clear detection of tumors as early as 4 h later, which improved over time to give a maximal tumor/normal ratio (TNR = 2.9 +/- 0.5) 24 h later. Similar results were observed for orthotopic MDA-MB-231 breast tumors. Localization of 800CW-PGN635 to tumors was antigen specific since 800CW-Aurexis, a control probe of irrelevant specificity, did not localize to the tumors, and pre-administration of unlabeled PGN635 blocked the uptake of 800CW-PGN635. Fluorescence microscopy confirmed that 800CW-PGN635 was binding to PS-positive tumor vascular endothelium. Our studies suggest that tumor vasculature can be successfully imaged in vivo to provide sensitive tumor detection.

  10. Ablation of the androgen receptor from vascular smooth muscle cells demonstrates a role for testosterone in vascular calcification.

    Science.gov (United States)

    Zhu, Dongxing; Hadoke, Patrick W F; Wu, Junxi; Vesey, Alex T; Lerman, Daniel A; Dweck, Marc R; Newby, David E; Smith, Lee B; MacRae, Vicky E

    2016-01-01

    Vascular calcification powerfully predicts mortality and morbidity from cardiovascular disease. Men have a greater risk of cardiovascular disease, compared to women of a similar age. These gender disparities suggest an influence of sex hormones. Testosterone is the primary and most well-recognised androgen in men. Therefore, we addressed the hypothesis that exogenous androgen treatment induces vascular calcification. Immunohistochemical analysis revealed expression of androgen receptor (AR) in the calcified media of human femoral artery tissue and calcified human valves. Furthermore, in vitro studies revealed increased phosphate (Pi)-induced mouse vascular smooth muscle cell (VSMC) calcification following either testosterone or dihydrotestosterone (DHT) treatment for 9 days. Testosterone and DHT treatment increased tissue non-specific alkaline phosphatase (Alpl) mRNA expression. Testosterone-induced calcification was blunted in VSMC-specific AR-ablated (SM-ARKO) VSMCs compared to WT. Consistent with these data, SM-ARKO VSMCs showed a reduction in Osterix mRNA expression. However, intriguingly, a counter-intuitive increase in Alpl was observed. These novel data demonstrate that androgens play a role in inducing vascular calcification through the AR. Androgen signalling may represent a novel potential therapeutic target for clinical intervention. PMID:27095121

  11. Effect of lovastatin on rabbit vascular smooth muscle cells

    International Nuclear Information System (INIS)

    Objective: To investigate the effect of lovastatin on binding activity of nuclear factor activator protein-1 (AP-1) to NF-κB and the expression of matrix metalloproteinase-9 (MMP-9) in rabbit vascular smooth muscle cells (VSMCs). Methods: The oligonucleotide corresponding to the consensus NF-κB element or the consensus AP-1 element was labeled by [γ-32P]-ATP. AP-1 and NF-κB binding activity was detected by electrophoretic mobility shift assay (EMSA), expression of MMP-9 was detected by zymography. Results: Lovastatin inhibited the expression of MMP-9 in a dose-dependent manner, this effect was reversed by mevalonate and GGPP but not by squalene; lovastatin significantly decreased AP-1 and NF-κB binding activity. Conclusion: Lovastatin decreased AP-1 and NF-κB binding activity and inhibited MMP-9 expression in rabbit VSMCs by the way of inhibiting prenylation of protein but not by cholestrol-lowering, and this might be the mechanism of its arteriosclerostic plaque stabilizing effects

  12. Effect of Oxysterol-Induced Apoptosis of Vascular Smooth Muscle Cells on Experimental Hypercholesterolemia

    OpenAIRE

    2009-01-01

    Smooth muscle cells (SMCs) undergo changes related to proliferation and apoptosis in the physiological remodeling of vessels and in diseases such as atherosclerosis and restenosis. Recent studies also have demonstrated the vascular cell proliferation and programmed cell death contribute to changes in vascular architecture in normal development and in disease. The present study was designed to investigate the apoptotic pathways induced by 25-hydroxycholesterol in SMCs cultures, using an in viv...

  13. Unsuspected role for the T-cell leukemia protein SCL/tal-1 in vascular development

    OpenAIRE

    Visvader, Jane E.; Fujiwara, Yuko; Orkin, Stuart H.

    1998-01-01

    The transcription factor SCL/tal-1 is essential for blood cell development. Though it is also expressed in vascular endothelium, SCL has been considered dispensable for vessel formation. Through transgenic rescue of hematopoietic defects of SCL−/− embryos and analysis of chimeras generated with SCL−/− ES cells tagged with a transgene expressed in vascular endothelial cells, we show that SCL is essential for angiogenic remodeling of the yolk sac capillary network into complex vitelline vessels...

  14. Immune cells: more than simple carriers for systemic delivery of oncolytic viruses

    Directory of Open Access Journals (Sweden)

    Eisenstein S

    2014-11-01

    Full Text Available Samuel Eisenstein,1 Shu-Hsia Chen,2 Ping-Ying Pan21Department of Surgery, 2Department of Oncological Sciences and Tisch Cancer Institute, The Icahn School of Medicine at Mount Sinai, New York, NY, USAAbstract: Oncolytic virotherapy on its own has numerous drawbacks, including an inability of the virus to actively target tumor cells and systemic toxicities at the high doses necessary to effectively treat tumors. Addition of immune cell-based carriers of oncolytic viruses holds promise as a technique in which oncolytic virus can be delivered directly to tumors in smaller and less toxic doses. Interestingly, the cell carriers themselves have also demonstrated antitumor effects, which can be augmented further by tailoring the appropriate oncolytic virus to the appropriate cell type. This review discusses the multiple factors that go into devising an effective, cell-based delivery system for oncolytic viruses.Keywords: oncolytic virus, cell carrier, immune cells, cancer therapy, myeloid-derived suppressor cells

  15. 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. PMID:27194709

  16. Biomedical Application of Low Molecular Weight Heparin/Protamine Nano/Micro Particles as Cell- and Growth Factor-Carriers and Coating Matrix

    Science.gov (United States)

    Ishihara, Masayuki; Kishimoto, Satoko; Takikawa, Makoto; Hattori, Hidemi; Nakamura, Shingo; Shimizu, Masafumi

    2015-01-01

    Low molecular weight heparin (LMWH)/protamine (P) nano/micro particles (N/MPs) (LMWH/P N/MPs) were applied as carriers for heparin-binding growth factors (GFs) and for adhesive cells including adipose-derived stromal cells (ADSCs) and bone marrow-derived mesenchymal stem cells (BMSCs). A mixture of LMWH and P yields a dispersion of N/MPs (100 nm–3 μm in diameter). LMWH/P N/MPs can be immobilized onto cell surfaces or extracellular matrix, control the release, activate GFs and protect various GFs. Furthermore, LMWH/P N/MPs can also bind to adhesive cell surfaces, inducing cells and LMWH/P N/MPs-aggregate formation. Those aggregates substantially promoted cellular viability, and induced vascularization and fibrous tissue formation in vivo. The LMWH/P N/MPs, in combination with ADSCs or BMSCs, are effective cell-carriers and are potential promising novel therapeutic agents for inducing vascularization and fibrous tissue formation in ischemic disease by transplantation of the ADSCs and LMWH/P N/MPs-aggregates. LMWH/P N/MPs can also bind to tissue culture plates and adsorb exogenous GFs or GFs from those cells. The LMWH/P N/MPs-coated matrix in the presence of GFs may provide novel biomaterials that can control cellular activity such as growth and differentiation. Furthermore, three-dimensional (3D) cultures of cells including ADSCs and BMSCs using plasma-medium gel with LMWH/P N/MPs exhibited efficient cell proliferation. Thus, LMWH/P N/MPs are an adequate carrier both for GFs and for stromal cells such as ADSCs and BMSCs, and are a functional coating matrix for their cultures. PMID:26006248

  17. Cell Phone Carriers, TV-Commercials & Branding : A study of cell phone carriers TV- commercials, branding and its affect on young people

    OpenAIRE

    Sköld, Robin; Nilsson, Magnus

    2009-01-01

    Problem: As almost everyone has a cell phone today, keeping your customers is very important. An important group for cell phone carriers is young people. This is a group that uses cell phones more and more. However, attracting these people could be hard. One of the most common strategies to attract customers today is promotion through TV-commercials. Another strategy that has gained popularity is branding. We therefore asked ourselves how these strategies could affect each other and eventuall...

  18. Carbon nanotubes as VEGF carriers to improve the early vascularization of porcine small intestinal submucosa in abdominal wall defect repair

    Directory of Open Access Journals (Sweden)

    Liu Z

    2014-03-01

    Full Text Available Zhengni Liu,1,* Xueyi Feng,2,* Huichun Wang,1 Jun Ma,1 Wei Liu,3 Daxiang Cui,4 Yan Gu,1 Rui Tang,11Department of General Surgery, Shanghai Ninth People’s Hospital, Hernia and Abdominal Wall Disease Center, Shanghai Jiao Tong University School of Medicine, Shanghai, People’s Republic of China; 2Department of General Surgery, Lu’an People’s Hospital, Lu’an Affiliated Hospital of Anhui Medical University, Lu’an, Province Anhui, People’s Republic of China; 3Department of Plastic and Reconstructive Surgery, Shanghai Ninth People’s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Tissue Engineering, Shanghai, People’s Republic of China; 4Institute of Nano Biomedicine and Engineering, Key Laboratory for Thin Film and Microfabrication Technology of the Ministry of Education, Research Institute of Micro/Nano Science and Technology, Bio-X Center, Shanghai Jiao Tong University, Shanghai, People's Republic of China *These authors contributed equally to this work Abstract: Insufficient early vascularization in biological meshes, resulting in limited host tissue incorporation, is thought to be the primary cause for the failure of abdominal wall defect repair after implantation. The sustained release of exogenous angiogenic factors from a biocompatible nanomaterial might be a way to overcome this limitation. In the study reported here, multiwalled carbon nanotubes (MWNT were functionalized by plasma polymerization to deliver vascular endothelial growth factor165 (VEGF165. The novel VEGF165-controlled released system was incorporated into porcine small intestinal submucosa (PSIS to construct a composite scaffold. Scaffolds incorporating varying amounts of VEGF165-loaded functionalized MWNT were characterized in vitro. At 5 weight percent MWNT, the scaffolds exhibited optimal properties and were implanted in rats to repair abdominal wall defects. PSIS scaffolds incorporating VEGF165-loaded MWNT (VEGF

  19. 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.

  20. Rosiglitzone Suppresses Angiotensin II-Induced Production of KLF5 and Cell Proliferation in Rat Vascular Smooth Muscle Cells

    OpenAIRE

    Gao, Dengfeng; Hao, Guanghua; Meng, Zhe; Ning, Ning; Yang, Guang; Liu, Zhongwei; Dong, Xin; Niu, Xiaolin

    2015-01-01

    Krüppel-like factor (KLF) 5, which initiates vascular smooth muscle cell (VSMC) proliferation, also participates in Angiotensin (Ang) II-induced vascular remodeling. The protective effect of rosiglitazone on vascular remodeling may be due to their impact on VSMC proliferation. However, the underlying mechanisms involved remain unclear. This study was designed to investigate whether the antiproliferation effects of rosiglitazone are mediated by regulating Ang II/KLF5 response. We found that, i...

  1. A study of ethanol production of yeast cells immobolized with polymer carrier produced by radiation polymerization

    Science.gov (United States)

    Zhaoxin, Lu; Fujimura, Takashi

    1993-10-01

    Polymer carriers, poly(hydroxyethyl acrylate(HEA)-methoxy polyethylene glycol methylacrylate (M-23G)) and poly (hydroxyethyl accrylate(HEA)-glycidyl methlacrylate(GMA)) using for immobilization of yeast cells were prepared by radiation polymerization at low temperature. Yeast cells were immobilized through adhesion and multiplication of yeast cells themselves. The ethanol productivity of immobilized yeast cells with these carriers was related to the monomer composition of polymers and the optimum monomer composition was 20% : 10% in poly(HEA-M-23G) and 17%: 6% in poly(HEA-GMA). In this case, the ethanol productivity of immobilized yeast cells was 29mg/ml/h which was about 4 times that of cells in free system. The relationship between the activity of immobilized yeast cells and the water content of polymer carrier were also discussed.

  2. A study of ethanol production of yeast cells immobilized with polymer carrier produced by radiation polymerization

    International Nuclear Information System (INIS)

    Polymer carriers, poly(hydroxyethyl acrylate(HEA)-methoxy polyethylene glycol methylacrylate (M-23G)) and poly(hydroxyethyl acrylate(HEA)-glycidyl methylacrylate (GMA)) used for the immobilization of yeast cells were prepared by radiation polymerization at low temperature. Yeast cells were immobilized through adhesion and multiplication of yeast cells. The ethanol productivity of immobilized yeast cells with these carriers was related to the monomer composition of polymers and the optimum monomer composition was 20%:10% in poly(HEA-M-23G) and 17%:6% in poly(HEA-GMA). In this case, the ethanol productivity of immobilized yeast cells was about 4 times that of cells in free system. The relationship between the activity of immobilized yeast cells and the water content of the polymer carrier were also discussed. (author)

  3. Mesenchymal stem cells-derived vascular smooth muscle cells release abundant levels of osteoprotegerin

    Directory of Open Access Journals (Sweden)

    M Vaccarezza

    2009-03-01

    Full Text Available Although several studies have shown that the serum levels of osteoprotegerin (OPG are significantly elevated in patients affected with atherosclerotic lesions in coronary and peripheral arteries, the cellular source and the role of OPG in the physiopathology of atherosclerosis are not completely defined. Therefore, we aimed to investigate the potential contribution of mesenchymal stem cells in the production/release of OPG. OPG was detectable by immunohistochemistry in aortic and coronary atherosclerotic plaques, within or in proximity of intimal vascular smooth muscle cells (SMC. In addition, bone marrow mesenchymal stem cell (MSC-derived vascular SMC as well as primary aortic SMC released in the culture supernatant significantly higher levels of OPG with respect to MSCderived endothelial cells (EC or primary aortic EC. On the other hand, in vitro exposure to full-length human recombinant OPG significantly increased the proliferation rate of aortic SMC cultures, as monitored by bromodeoxyuridine incorporation. Taken together, these data suggest that OPG acts as an autocrine/paracrine growth factor for vascular SMC, which might contribute to the progression of atherosclerotic lesions.

  4. 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 in...... subcutaneous white adipose tissue (WAT) provide a reliable cellular system to study the molecular control of beige/brite cell development. Here we describe a protocol for effective isolation of primary preadipocytes and for inducing differentiation to beige/brite cells in culture. The browning effect can be...

  5. Cheiradone: a vascular endothelial cell growth factor receptor antagonist

    Directory of Open Access Journals (Sweden)

    Ahmed Nessar

    2008-01-01

    Full Text Available Abstract Background Angiogenesis, the growth of new blood vessels from the pre-existing vasculature is associated with physiological (for example wound healing and pathological conditions (tumour development. Vascular endothelial growth factor (VEGF, fibroblast growth factor-2 (FGF-2 and epidermal growth factor (EGF are the major angiogenic regulators. We have identified a natural product (cheiradone isolated from a Euphorbia species which inhibited in vivo and in vitro VEGF- stimulated angiogenesis but had no effect on FGF-2 or EGF activity. Two primary cultures, bovine aortic and human dermal endothelial cells were used in in vitro (proliferation, wound healing, invasion in Matrigel and tube formation and in vivo (the chick chorioallantoic membrane models of angiogenesis in the presence of growth factors and cheiradone. In all cases, the concentration of cheiradone which caused 50% inhibition (IC50 was determined. The effect of cheiradone on the binding of growth factors to their receptors was also investigated. Results Cheiradone inhibited all stages of VEGF-induced angiogenesis with IC50 values in the range 5.20–7.50 μM but did not inhibit FGF-2 or EGF-induced angiogenesis. It also inhibited VEGF binding to VEGF receptor-1 and 2 with IC50 values of 2.9 and 0.61 μM respectively. Conclusion Cheiradone inhibited VEGF-induced angiogenesis by binding to VEGF receptors -1 and -2 and may be a useful investigative tool to study the specific contribution of VEGF to angiogenesis and may have therapeutic potential.

  6. Immobilization of yeast cells with various porous carriers by radiation-induced polymerization

    International Nuclear Information System (INIS)

    Yeast cells were immobilized by radiation-induced polymerization in twice. Various kinds of porous polymer carriers were prepared by radiation-induced polymerization of glass-forming monomers at a low temperature. Precultured yeast cells were incubated aerobically at 300C with these porous carriers for 24 h. Porous carriers with yeast cells were immersed in low concentration monomer solution. Yeast cells were immobilized by radiation-induced polymerization. The maximum ethanol productivity in immobilized yeast system was around 10 times as much as that in free yeast cell system. High activity of immobilized yeast cells was maintained more than 480 h. The growth of yeast cells in immobilized yeast cells during aerobical incubation was indicated. Immobilized yeast cells thus grown were incubated for fermentation reaction. In this immobilized system, 100% of glucose was converted to ethanol, that is 100% ethanol yield was obtained, within 180 min. In free cell system, only 15% ethanol yield was obtained within 180 min. These results indicates clearly the superiority of immobilized growing cell. Yeast cells were also immobilized with non woven material as carrier by radiation-induced polymerization. The relationship between pore size of non woven material and activity in immobilized yeast cells was made clear. (author)

  7. UBIAD1-mediated vitamin K2 synthesis is required for vascular endothelial cell survival and development

    OpenAIRE

    Hegarty, Jeffrey M.; Yang, Hongbo; Chi, Neil C.

    2013-01-01

    Multi-organ animals, such as vertebrates, require the development of a closed vascular system to ensure the delivery of nutrients to, and the transport of waste from, their organs. As a result, an organized vascular network that is optimal for tissue perfusion is created through not only the generation of new blood vessels but also the remodeling and maintenance of endothelial cells via apoptotic and cell survival pathways. Here, we show that UBIAD1, a vitamin K2/menaquinone-4 biosynthetic en...

  8. Hyaluronan oligosaccharides perturb lymphocyte slow rolling on brain vascular endothelial cells: Implications for inflammatory demyelinating disease

    OpenAIRE

    Winkler, Clayton W.; Foster, Scott C.; Itakura, Asako; Matsumoto, Steven G.; Asari, Akira; McCarty, Owen J. T.; Sherman, Larry S.

    2013-01-01

    Inflammatory demyelinating diseases like multiple sclerosis are characterized by mononuclear cell infiltration into the central nervous system. The glycosaminoglycan hyaluronan and its receptor, CD44, are implicated in the initiation and progression of a mouse model of multiple sclerosis, experimental autoimmune encephalomyelitis (EAE). Digestion of hyaluronan tethered to brain vascular endothelial cells by a hyaluronidase blocks the slow rolling of lymphocytes along activated brain vascular ...

  9. Carbon Nanotubes: An Emerging Drug Carrier for Targeting Cancer Cells

    OpenAIRE

    Vaibhav Rastogi; Pragya Yadav; Shiv Sankar Bhattacharya; Arun Kumar Mishra; Navneet Verma; Anurag Verma; Jayanta Kumar Pandit

    2014-01-01

    During recent years carbon nanotubes (CNTs) have been attracted by many researchers as a drug delivery carrier. CNTs are the third allotropic form of carbon-fullerenes which were rolled into cylindrical tubes. To be integrated into the biological systems, CNTs can be chemically modified or functionalised with therapeutically active molecules by forming stable covalent bonds or supramolecular assemblies based on noncovalent interactions. Owing to their high carrying capacity, biocompatibility,...

  10. 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.

  11. 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

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

    International Nuclear Information System (INIS)

    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

  13. 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.

  14. Biomaterials as carrier, barrier and reactor for cell-based regenerative medicine

    OpenAIRE

    Qi, Chunxiao; Yan, Xiaojun; Huang, Chenyu; Melerzanov, Alexander; Du, Yanan

    2015-01-01

    Cell therapy has achieved tremendous success in regenerative medicine in the past several decades. However, challenges such as cell loss, death and immune-rejection after transplantation still persist. Biomaterials have been designed as carriers to deliver cells to desirable region for local tissue regeneration; as barriers to protect transplanted cells from host immune attack; or as reactors to stimulate host cell recruitment, homing and differentiation. With the assistance of biomaterials, ...

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

    Directory of Open Access Journals (Sweden)

    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.

  16. Coseeded Schwann cells myelinate neurites from differentiated neural stem cells in neurotrophin-3-loaded PLGA carriers.

    Science.gov (United States)

    Xiong, Yi; Zhu, Ji-Xiang; Fang, Zheng-Yu; Zeng, Cheng-Guang; Zhang, Chao; Qi, Guo-Long; Li, Man-Hui; Zhang, Wei; Quan, Da-Ping; Wan, Jun

    2012-01-01

    Biomaterials and neurotrophic factors represent promising guidance for neural repair. In this study, we combined poly-(lactic acid-co-glycolic acid) (PLGA) conduits and neurotrophin-3 (NT-3) to generate NT-3-loaded PLGA carriers in vitro. Bioactive NT-3 was released stably and constantly from PLGA conduits for up to 4 weeks. Neural stem cells (NSCs) and Schwann cells (SCs) were coseeded into an NT-releasing scaffold system and cultured for 14 days. Immunoreactivity against Map2 showed that most of the grafted cells (>80%) were differentiated toward neurons. Double-immunostaining for synaptogenesis and myelination revealed the formation of synaptic structures and myelin sheaths in the coculture, which was also observed under electron microscope. Furthermore, under depolarizing conditions, these synapses were excitable and capable of releasing synaptic vesicles labeled with FM1-43 or FM4-64. Taken together, coseeding NSCs and SCs into NT-3-loaded PLGA carriers increased the differentiation of NSCs into neurons, developed synaptic connections, exhibited synaptic activities, and myelination of neurites by the accompanying SCs. These results provide an experimental basis that supports transplantation of functional neural construction in spinal cord injury. PMID:22619535

  17. Resveratrol Induces Vascular Smooth Muscle Cell Differentiation through Stimulation of SirT1 and AMPK

    OpenAIRE

    Anne Marie Thompson; Martin, Kathleen A.; Rzucidlo, Eva M.

    2014-01-01

    Phenotypic plasticity in vascular smooth muscle cells (VSMC) is necessary for vessel maintenance, repair and adaptation to vascular changes associated with aging. De-differentiated VSMC contribute to pathologies including atherosclerosis and intimal hyperplasia. As resveratrol has been reported to have cardio- protective effects, we investigated its role in VSMC phenotypic modulation. We demonstrated the novel finding that resveratrol promoted VSMC differentiation as measured by contractile p...

  18. Smooth muscle cell mineralocorticoid receptors: role in vascular function and contribution to cardiovascular disease

    OpenAIRE

    McCurley, Amy; McGraw, Adam; Pruthi, Dafina; Jaffe, Iris Z.

    2013-01-01

    The mineralocorticoid receptor (MR), a member of the steroid receptor family, regulates blood pressure by mediating the effects of the hormone aldosterone on renal sodium handling. In recent years, it has become clear that MR is expressed in vascular smooth muscle cells (SMC) and interest has grown in understanding the direct role of SMC MR in regulating vascular function. This interest stems from multiple clinical studies where MR inhibitor treatment reduced the incidence of cardiovascular e...

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

    Directory of Open Access Journals (Sweden)

    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.

  20. Coseeded Schwann cells myelinate neurites from differentiated neural stem cells in neurotrophin-3-loaded PLGA carriers

    Directory of Open Access Journals (Sweden)

    Xiong Y

    2012-04-01

    Full Text Available Yi Xiong1,*, Ji-Xiang Zhu2,*, Zheng-Yu Fang1, Cheng-Guang Zeng2, Chao Zhang1, Guo-Long Qi3, Man-Hui Li1, Wei Zhang1, Da-Ping Quan2, Jun Wan1,41Biomedical Research Institute, Shenzhen-PKU-HKUST Medical Center, Shenzhen, 2DSAPM Lab, PCFM Lab, Institute of Polymer Science, School of Chemistry and Chemical Engineering, Sun Yat-sen University, Guangzhou, 3Department of Medical Information, Medical Collage of Jinan University, Guangzhou, 4Division of Life Science, the Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, People's Republic of China*These authors contributed equally to this manuscriptAbstract: Biomaterials and neurotrophic factors represent promising guidance for neural repair. In this study, we combined poly-(lactic acid-co-glycolic acid (PLGA conduits and neurotrophin-3 (NT-3 to generate NT-3-loaded PLGA carriers in vitro. Bioactive NT-3 was released stably and constantly from PLGA conduits for up to 4 weeks. Neural stem cells (NSCs and Schwann cells (SCs were coseeded into an NT-releasing scaffold system and cultured for 14 days. Immunoreactivity against Map2 showed that most of the grafted cells (>80% were differentiated toward neurons. Double-immunostaining for synaptogenesis and myelination revealed the formation of synaptic structures and myelin sheaths in the coculture, which was also observed under electron microscope. Furthermore, under depolarizing conditions, these synapses were excitable and capable of releasing synaptic vesicles labeled with FM1-43 or FM4-64. Taken together, coseeding NSCs and SCs into NT-3-loaded PLGA carriers increased the differentiation of NSCs into neurons, developed synaptic connections, exhibited synaptic activities, and myelination of neurites by the accompanying SCs. These results provide an experimental basis that supports transplantation of functional neural construction in spinal cord injury.Keywords: PLGA, NT-3, neural stem cells, Schwann cells, myelin sheath

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

    Science.gov (United States)

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

    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 9days, 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. PMID:27524062

  2. Reversible electron-hole separation in a hot carrier solar cell

    Science.gov (United States)

    Linke, Heiner

    Hot-carrier solar cells are envisioned to utilize energy filtering to extract power from photogenerated electron-hole pairs before they thermalize with the lattice, and thus potentially offer higher power conversion efficiency compared to conventional, single absorber solar cells. The efficiency of hot-carrier solar cells can be expected to strongly depend on the details of the energy filtering process, a relationship which to date has not been satisfactorily explored. Here, we establish the conditions under which electron-hole separation in hot-carrier solar cells can occur reversibly, that is, at maximum energy conversion efficiency. We find that, under specific conditions, the energy conversion efficiency of a hot-carrier solar cell can exceed the Carnot limit set by the intra-device temperature gradient alone, due to the additional contribution of the quasi-Fermi level splitting in the absorber. To achieve this, we consider a highly selective energy filter such as a quantum dot embedded into a one-dimensional conductor. We also establish that the open-circuit voltage of a hot-carrier solar cell is not limited by the band gap of the absorber, due to the additional thermoelectric contribution to the voltage. Additionally, we find that a hot-carrier solar cell can be operated in reverse as a thermally driven solid-state light emitter. In addition this theoretical analysis, I will also report on first experimental results in a nanowire-based energy filter device. Ref: S Limpert, S Bremner, and H Linke, New J. Phys 17, 095004 (2015)

  3. Molecular biology of breast cancer metastasis Molecular expression of vascular markers by aggressive breast cancer cells

    International Nuclear Information System (INIS)

    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

  4. Human fetal aorta-derived vascular progenitor cells: identification and potential application in ischemic diseases

    OpenAIRE

    Invernici, Gloria; Madeddu, Paolo; Emanueli, Costanza; Parati, Eugenio A.; Alessandri, Giulio

    2008-01-01

    Vasculogenesis, the formation of blood vessels in embryonic or fetal tissue mediated by immature vascular cells (i.e., angioblasts), is poorly understood. Here we report a summary of our recent studies on the identification of a population of vascular progenitor cells (VPCs) in human fetal aorta. These undifferentiated mesenchymal cells co-express endothelial and myogenic markers (CD133+, CD34+, KDR+, desmin+) and are localized in outer layer of the aortic stroma of 11–12 weeks old human fetu...

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

    Directory of Open Access Journals (Sweden)

    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

  6. RNA interference inhibits expression of vascular endothelial growth factor (VEGF) in human retinal pigment epithelial cells

    Institute of Scientific and Technical Information of China (English)

    CAI Chun-mei; SUN Bao-chen; LIU Xu-yang; WANG Jin-jin; LI Jun-fa; HAN Song; WANG Ning-li; LU Qing-jun

    2005-01-01

    @@ Choroidal neovascularization (CNV), a major cause of vision loss, is the result of the increased vascular endothelial growth factor (VEGF) expression in human retinal pigment epithelial (RPE) cells. It is important to inhibit the expression of VEGF protein in RPE cells.

  7. Spatial development of the cultivation of a bone marrow stromal cell line in porous carriers.

    Science.gov (United States)

    Takagi, M; Sasaki, T; Yoshida, T

    1999-11-01

    The spatial development of the cultivation of a bone marrow stromal cell line (SR-4987) in porous carriers was investigated in order to construct a three-dimensional hematopoietic culture system. Low-rate continuous agitation, 20 rpm, was an appropriate method to achieve initial adhesion of cells onto a cellulose porous beads (CPB, 100 mum pore diameter) in a spinner bottle, compared with other methods such as centrifugation and intermittent agitation. Cell growth with continuous agitation at 70 rpm after initial cell adhesion was not inferior to that at 20 rpm. A 2- and 10-fold increase in the inoculum cell concentration for CPB and another type of porous cellulose beads (Micro-cube (MC), 500 mum pore diameter) resulted in a 1.2- and 2-fold increase in final cell concentrationm, respectively. Cells attached to the MC beads and a polyester nonwoven dic (Fibra-cell (FC)) could grow and spread well on the carriers and a fibroblast-like shape was observed under scanning electron microscopy while the cells on CPB were globular. The flatness and inner surface area of these carriers may be the reason for the differences in cell morphology. PMID:19003146

  8. Disturbance of Copper Homeostasis Is a Mechanism for Homocysteine-Induced Vascular Endothelial Cell Injury

    OpenAIRE

    Dong, Daoyin; Wang, Biao; Yin, Wen; Ding, Xueqing; Yu, Jingjing; Kang, Y James

    2013-01-01

    Elevation of serum homocysteine (Hcy) levels is a risk factor for cardiovascular diseases. Previous studies suggested that Hcy interferes with copper (Cu) metabolism in vascular endothelial cells. The present study was undertaken to test the hypothesis that Hcy-induced disturbance of Cu homeostasis leads to endothelial cell injury. Exposure of human umbilical vein endothelial cells (HUVECs) to concentrations of Hcy at 0.01, 0.1 or 1 mM resulted in a concentration-dependent decrease in cell vi...

  9. Cell proliferation in the murine epidermis and subcutaneous vascular endothelium after hyperthermia

    International Nuclear Information System (INIS)

    The proliferation characteristics of the vascular endothelial cells in the subepidermal stoma were investigated after heat treatment using [3H] thymidine labelling and labelling of epidermal basal cells studied and compared with endothelium cells. The stimulated proliferation of subcutaneous endothelial cells after heating for 30 and 60 min at 440C correlated well with the finding that these heat treatments, given after or shortly before X-irradiation, led to a greatly reduced (X-ray induced) tumour bed effect. (author)

  10. Physiological tests for yeast brewery cells immobilized on modified chamotte carrier

    OpenAIRE

    Berlowska, Joanna; Kregiel, Dorota; Ambroziak, Wojciech

    2013-01-01

    In this study yeast cell physiological activity was assessed on the basis of the in situ activity of two important enzymes, succinate dehydrogenase and pyruvate decarboxylase. FUN1 dye bioconversion and cellular ATP content were also taken as important indicators of yeast cell activity. The study was conducted on six brewing yeast strains, which were either free cells or immobilized on a chamotte carrier. The experimental data obtained indicate clearly that, in most cases, the immobilized cel...

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

    International Nuclear Information System (INIS)

    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.Tgfbr2f/f) and their corresponding wild-type background mice (MyhCre.Tgfbr2WT/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

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  13. Glucose and Inflammatory Cells Decrease Adiponectin in Epicardial Adipose Tissue Cells: Paracrine Consequences on Vascular Endothelium.

    Science.gov (United States)

    Fernández-Trasancos, Ángel; Guerola-Segura, Raquel; Paradela-Dobarro, Beatriz; Álvarez, Ezequiel; García-Acuña, José María; Fernández, Ángel Luis; González-Juanatey, José Ramón; Eiras, Sonia

    2016-05-01

    Epicardial adipose tissue (EAT) is a source of energy for heart that expresses the insulin-sensitizer, anti-inflammatory and anti-atherogenic protein, adiponectin. But, in coronary artery disease, adiponectin production declines. Our objective was to determine its regulation by glucose and inflammation in stromal cells from EAT and subcutaneous adipose tissue (SAT) and its paracrine effect on endothelial cells. Stromal cells of EAT and SAT were obtained from patients who underwent cardiac surgery. Adipogenesis was induced at 117, 200, or 295 mg/dl glucose, with or without macrophage-conditioned medium (MCM). Expression of adiponectin, GLUT-4 and the insulin receptor was analyzed by real-time PCR. The paracrine effect of stromal cells was determined in co-cultures with endothelial cells, by exposing them to high glucose and/or MCM, and, additionally, to leukocyte-conditioned medium from patients with myocardial infarction. The endothelial response was determined by analyzing vascular adhesion molecule expression. Our results showed a U-shaped dose-response curve of glucose on adiponectin in EAT, but not in SAT stromal cells. Conversely, MCM reduced the adipogenesis-induced adiponectin expression of EAT stromal cells. The presence of EAT stromal increased the inflammatory molecules of endothelial cells. This deleterious effect was emphasized in the presence of inflammatory cell-conditioned medium from patients with myocardial infarction. Thus, high glucose and inflammatory cells reduced adipogenesis-induced adiponectin expression of EAT stromal cells, which induced an inflammatory paracrine process in endothelial cells. This inflammatory effect was lower in presence of mature adipocytes, producers of adiponectin. These results contribute to understanding the role of EAT dysfunction on coronary atherosclerosis progression. PMID:26406271

  14. Carrier extraction dynamics from Ge/Si quantum wells in Si solar cells

    International Nuclear Information System (INIS)

    To address the carrier extraction mechanism that determines the fundamental characteristics, such as current density, open circuit voltage, and fill factor in nanostructure-based solar cells, we performed photoluminescence (PL) decay measurements of the Ge/Si quantum wells (QWs) in crystalline-silicon (c-Si) solar cells. We found that the PL decay time of Ge/Si QWs depends on the temperature and the applied electric field; this dependence reflects the carrier separation characteristics of electron–hole pairs in Ge/Si QWs. Above ∼ 40 K, the electron–hole pairs are rapidly separated by the thermal excitation and the built-in electric field of c-Si solar cells. In contrast, at 20 K the PL decay time remains almost unchanged for an applied electric field of up to ± 1 V. These results indicate that the electrons confined in the type-II band offsets could be thermally excited and then extracted by an applied electric field. - Highlights: • Carrier extraction mechanism in nanostructure-based solar cells • Photoluminescence dynamics in Ge/Si quantum wells in Si solar cellsCarrier separation characteristics of electron-hole pairs in type-II Ge/Si QWs

  15. Simple spinner bottle with rotating basket packed with carriers for hybridoma cell culture.

    Science.gov (United States)

    Chen, Y; Wang, G; Zhang, W; Freedman, D

    1996-01-01

    r-69B is a mouse-mouse hybridoma cell line, producing monoclonal antibody IgG against human r-IFN. It was cultured for 21 days in the 1.0-L spinner bottle which was assembled with a rotating basket packed with the 8.0-g Fibra-Cel carriers. The agitation was 100 r/min. The results showed that 53.5% of the cells can be trapped within the carriers in the basket and the cell concentration and MAb was about double those in the suspension culture. The spinner bottle could be assembled simply and used in general laboratories. It also could be used for different kinds of cells, including anchorage-dependent and independent cells. PMID:9093764

  16. Immobilization of Gibberella fujikuroi cells with carriers modified by radiation polymerization

    International Nuclear Information System (INIS)

    Gibberella fujikuroi cells were immobilized on modified carriers (gauze) by using the radiation polymerization technique. The mycelium was firmly adhered to the surface of fibril covered with hydrophobic polymer, poly (diethylene glycol dimethyl acrylate) and hydrophobic-hydrophilic copolymer poly (diethylene glycol dimethyl acrylate-sodium acrylate), but it was not immobilized onto the polyethylene net, which has a similar network structure to that of the modified carrier. The weight of immobilized cells was affected by covered polymer. Gibberellic acid productivity in immobilized cells was similar to that of free cells, and the immobilized cells was of good stability. A optimum culture condition for gibberellic acid production was at pH 5.5 and under 20 ∼ 30 degree C

  17. Improved carrier extraction of solar cell using transparent current spreading layer

    International Nuclear Information System (INIS)

    An as-deposited ultra thin metal film was fine-etched to a mesh with average optical transmittance of 70.83%. When this metal mesh was applied to the fabrication of solar cell, it was transparent and conductive to be used as a current-spreading layer. Such a current-spreading layer was good for the carrier extraction of illuminated solar cell. Then the non-uniform two-dimensional current flow on the resistive central emitter region of solar cell can be reduced efficiently by this metal mesh. The metal mesh integrated solar cell can result in improvements of 26.15% for short-circuit current and 30% for the conversion efficiency, respectively. - Highlights: • An as-deposited thin metal thin film is fine-etched to a transparent mesh. • A transparent metal mesh acts as a current-spreading layer for solar cells. • A transparent metal mesh allows photons going through and carriers conducting

  18. Mast Cells and Histamine: Do They Influence Placental Vascular Network and Development in Preeclampsia?

    Directory of Open Access Journals (Sweden)

    Grzegorz Szewczyk

    2012-01-01

    Full Text Available The physiological course of pregnancy is closely related to adequate development of the placenta. Shallow invasion of trophoblast as well as decreased development of the placental vascular network are both common features of preeclampsia. To better understand the proangiogenic features of mast cells, in this study we aim to identify the potential relationship between the distribution of mast cells within the placenta and vascular network development. Material and Methods. Placentas from preeclampsia-complicated pregnancies (=11 and from physiological pregnancies (=11 were acquired after cesarean section. The concentration of histamine was measured, and immunohistochemical staining for mast cell tryptase was performed. Morphometric analysis was then performed. Results. We noticed significant differences between the examined groups. Notably, in the preeclampsia group compared to the control group, we observed a higher mean histamine concentration, higher mast cell density (MCD, lower mean mast cell (MMCA and lower vascular/extravascular (V/EVT index. In physiological pregnancies, a positive correlation was observed between the histamine concentration and V/VEVT index as well as MCD and the V/VEVT index. In contrast, a negative correlation was observed between MMCA and the V/EVT index in physiological pregnancies. Conclusions. Based on the data from our study, we suggest that a differential distribution of mast cells and corresponding changes in the concentration of histamine are involved in the defective placental vascularization seen in preeclamptic placentas.

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

    International Nuclear Information System (INIS)

    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 3H-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

  20. Red blood cells serve as intravascular carriers of myeloperoxidase

    Czech Academy of Sciences Publication Activity Database

    Adam, M.; Gajdová, Silvie; Kolářová, Hana; Kubala, Lukáš; Lau, D.; Geisler, A.

    2014-01-01

    Roč. 74, SEP (2014), s. 353-363. ISSN 0022-2828 R&D Projects: GA ČR(CZ) GCP305/12/J038 Institutional support: RVO:68081707 Keywords : Myeloperoxidase * Erythrocyte * Cell membranes Subject RIV: BO - Biophysics Impact factor: 4.655, year: 2014

  1. Vascular dysfunction in diabetes: The endothelial progenitor cells as new therapeutic strategy.

    Science.gov (United States)

    Georgescu, Adriana

    2011-06-15

    The vascular endothelium is a critical determinant of diabetes-associated vascular complications, and improving endothelial function is an important target for therapy. Diabetes mellitus contributes to endothelial cell injury and dysfunction. Endothelial progenitor cells (EPCs) play a critical role in maintaining endothelial function and might affect the progression of vascular disease. EPCs are essential to blood vessel formation, can differentiate into mature endothelial cells, and promote the repair of damaged endothelium. In diabetes, the circulating EPC count is low and their functionality is impaired. The mechanisms that underlie this reduced count and impaired functionality are poorly understood. Knowledge of the status of EPCs is critical for assessing the health of the vascular system, and interventions that increase the number of EPCs and restore their angiogenic activity in diabetes may prove to be particularly beneficial. The present review outlines current thinking on EPCs' therapeutic potential in endothelial dysfunction in diabetes, as well as evidence-based perspectives regarding their use for vascular regenerative medicine. PMID:21860692

  2. Electrospun PELCL membranes loaded with QK peptide for enhancement of vascular endothelial cell growth.

    Science.gov (United States)

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

    2016-06-01

    One of the major challenges in tissue engineering of small-diameter vascular grafts is to inhibit intimal hyperplasia and keep long-term patency after implantation. Rapid endothelialization of the grafts could be an effective approach. In this study, QK, a peptide mimicking vascular endothelial growth factor, was selected as the bioactive substrate and loaded in electrospun membranes for enhancement of vascular endothelial cell growth. In detail, QK peptide was firstly introduced with poly(ethylene glycol) diacrylate into a thiolated chitosan solution that could transfer into hydrogel. Then, suspensions or emulsions of poly(ethylene glycol)-b-poly(L-lactide-co-ε-caprolactone) (PELCL) containing QK peptide (with or without chitosan hydrogel) were electrospun into fibrous membranes. For comparison, the electrospun PELCL membrane without QK was also fabricated. Results of release behaviors showed that the electrospun membranes, especially that contained chitosan hydrogel prepared by suspension electrospinning, could successfully encapsulate QK peptide and maintain its secondary structure after released. In vitro cell culture studies exhibited that the release of QK peptide could accelerate the proliferation of vascular endothelial cells in the 9 days. It was suggested that the electrospun PELCL membranes loaded with QK peptide might have potential applications in vascular tissue engineering. PMID:27107890

  3. 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

  4. Quantification of stromal vascular cell mechanics with a linear cell monolayer rheometer

    Energy Technology Data Exchange (ETDEWEB)

    Elkins, Claire M., E-mail: cma9@stanford.edu; Fuller, Gerald G. [Department of Chemical Engineering, Stanford University, Stanford, California 94305 (United States); Shen, Wen-Jun; Khor, Victor K.; Kraemer, Fredric B. [Division of Endocrinology, Gerontology and Metabolism, Stanford University, Stanford, California 94305 and Veterans Affairs Palo Alto Health Care System, Palo Alto, California 94304 (United States)

    2015-01-15

    Over the past few decades researchers have developed a variety of methods for measuring the mechanical properties of whole cells, including traction force microscopy, atomic force microscopy (AFM), and single-cell tensile testing. Though each of these techniques provides insight into cell mechanics, most also involve some nonideal conditions for acquiring live cell data, such as probing only one portion of a cell at a time, or placing the cell in a nonrepresentative geometry during testing. In the present work, we describe the development of a linear cell monolayer rheometer (LCMR) and its application to measure the mechanics of a live, confluent monolayer of stromal vascular cells. In the LCMR, a monolayer of cells is contacted on both top and bottom by two collagen-coated plates and allowed to adhere. The top plate then shears the monolayer by stepping forward to induce a predetermined step strain, while a force transducer attached to the top plate collects stress information. The stress and strain data are then used to determine the maximum relaxation modulus recorded after step-strain, G{sub r}{sup 0}, referred to as the zero-time relaxation modulus of the cell monolayer. The present study validates the ability of the LCMR to quantify cell mechanics by measuring the change in G{sub r}{sup 0} of a confluent cell monolayer upon the selective inhibition of three major cytoskeletal components (actin microfilaments, vimentin intermediate filaments, and microtubules). The LCMR results indicate that both actin- and vimentin-deficient cells had ∼50% lower G{sub r}{sup 0} values than wild-type, whereas tubulin deficiency resulted in ∼100% higher G{sub r}{sup 0} values. These findings constitute the first use of a cell monolayer rheometer to quantitatively distinguish the roles of different cytoskeletal elements in maintaining cell stiffness and structure. Significantly, they are consistent with results obtained using single-cell mechanical testing methods

  5. Biological behaviour and role of endothelial progenitor cells in vascular diseases

    Institute of Scientific and Technical Information of China (English)

    ZHANG Qiu-hua; SHE Ming-peng

    2007-01-01

    Obiective To review the biological behaviour of endothelial progenitor cells and their role in vascular diseases.Data sources The data used in this review were mainly from Medline and PubMed for relevant English language articles published from 1985 to March 2007.The search term was "endothelial progenitor cells".Study selection Articles about the biological behaviour of endothelial progenitor cells and their roles in the pathogenesis of vascular diseases such as atherogenesis were used.Results Progenitor cells in bone marrow,peripheral blood and adventitia can differentiate into mature endothelial cells (ECs).The progenitor cells,which express certain surface markers including AC133,CD34 and KDR,enable restoration of the microcirculation and ECs when injury or ischaemia occurs.Endothelial progenitor cells used in experimental models and clinical trials for ischaemic syndromes could restore endothelial integrity and inhibit neointima development.Moreover,their number and functional properties are influenced by certain cytokines and atherosclerotic risk factors.Impairment of the progenitor cells might limit the regenerative capacity,even lead to the development of atherosclerosis or other vascular diseases.Conclusions Endothelial progenitor cells have a particular role in prevention and treatment of certain cardiovascular diseases.However,many challenges remain in understanding differentiation of endothelial progenitor cells,their mobilization and revascularization.

  6. Influence of injected charge carriers on photocurrents in polymer solar cells

    NARCIS (Netherlands)

    Wehenkel, Dominique J.; Koster, L. Jan Anton; Wienk, Martijn M.; Janssen, Rene A. J.

    2012-01-01

    We determine and analyze the photocurrent Jph in polymer solar cells under conditions where, no, one, or two different charge carriers can be injected by choosing appropriate electrodes and compare the experimental results to simulations based on a drift-diffusion device model that accounts for phot

  7. 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

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

    International Nuclear Information System (INIS)

    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

  9. Differences in Valvular and Vascular Cell Responses to Strain in Osteogenic Media

    OpenAIRE

    Zannatul, Ferdous; Hanjoong, Jo; Robert M., Nerem

    2011-01-01

    Calcification is the primary cause of failure of bioprosthetic and tissue-engineered vascular and valvular grafts. We used tissue-engineered collagen gels containing human aortic smooth muscle cells (HASMC) and human aortic valvular interstitial cells (HAVIC) as a model to investigate cell-mediated differences in early markers of calcification. The HASMCs and HAVICs were isolated from non-sclerotic human tissues. After 21 days of culture in either regular or osteogenic media with or without 1...

  10. Non-expanded adipose stromal vascular fraction cell therapy for multiple sclerosis

    OpenAIRE

    Rodriguez Jorge; Alfaro Miguel; Lara Fabian; Solano Fabio; Wang Hao; Min Wei-Ping; Ichim Thomas E; Riordan Neil H; Harman Robert J; Patel Amit N; Murphy Michael P; Lee Roland R; Minev Boris

    2009-01-01

    Abstract The stromal vascular fraction (SVF) of adipose tissue is known to contain mesenchymal stem cells (MSC), T regulatory cells, endothelial precursor cells, preadipocytes, as well as anti-inflammatory M2 macrophages. Safety of autologous adipose tissue implantation is supported by extensive use of this procedure in cosmetic surgery, as well as by ongoing studies using in vitro expanded adipose derived MSC. Equine and canine studies demonstrating anti-inflammatory and regenerative effects...

  11. An ethanolic extract of Angelica gigas improves atherosclerosis by inhibiting vascular smooth muscle cell proliferation

    OpenAIRE

    Jang, Ja Young; Kim, Jihyun; Cai, Jingmei; Kim, Youngeun; Shin, Kyungha; Kim, Tae-Su; Lee, Sung-Pyo; Park, Sung Kyeong; Choi, Ehn-Kyoung; Kim, Yun-Bae

    2014-01-01

    The effects of an ethanolic extract of Angelica gigas (EAG) on the vascular smooth muscle cell (VSMC) proliferation and high-cholesterol diet-induced hypercholesterolemia and atherosclerosis were investigated. Rat aortic VSMCs were stimulated with platelet-derived growth factor-BB (25 ng/mL) for the induction of DNA synthesis and cell proliferation. EAG (1-10 µg/mL) significantly inhibited both the thymidine incorporation and cell proliferation in a concentration-dependent manner. Hypercholes...

  12. Vascular neuroprotection via TrkB- and Akt-dependent cell survival signaling

    OpenAIRE

    Guo, Shuzhen; Som, Angel T.; Waeber, Christian; Lo, Eng H.

    2012-01-01

    The cerebral endothelium can be a vital source of signaling factors such as brain-derived neurotrophic factor (BDNF) that defend the neuronal parenchyma against stress and injury. But the underlying mechanisms remain to be fully defined. Here, we use cell models to ask how vascular neuroprotection is sustained. Human brain endothelial cells were grown in culture and conditioned media was transferred to primary rat cortical neurons. Brain endothelial cell-conditioned media activated neuronal A...

  13. Three-Dimensional Cell Culture of Vascular Networks on Biomimetic Hydrogel Scaffolds

    OpenAIRE

    Hulkkonen, Hanna

    2015-01-01

    In vitro modeling of vascular development (angiogenesis) remains challenging since cell behavior may be abnormal in traditional, simplified monocultures. To mimic the extracellular matrix, 3D-printed and uniform fibrin and fibrin/gelatin hydrogels were fabricated to support capillary morphogenesis of human endothelial cells and adipose stromal cells. A microextrusion method was optimized for printing of patterned hydrogels. The effects of topography and hydrogel formulation on capillary l...

  14. An Important Method in the Investigation of Vascular Pathologies: Endothelial Cell Culture

    Directory of Open Access Journals (Sweden)

    Yusufhan Yazır

    2012-12-01

    Full Text Available Endothelial cells line the interior surface of blood vessels and form an interface between circulating blood in the lumen and the rest of the vessel wall. Endothelial cells are involved in many aspects of vascular biology, including barrier function, vasoconstriction, coagulation and inflamation. The endothelial cells in different organs have different functions and surface phenotype. These cells express prostoglandin-I2, platelet activating factor, collagen, endothelin-1, laminin, fibronectin and growth factors including platelet derived growth factor, fibroblast growth factor. İn the cell culture, cells can be isolated, maintened and proliferate in the laboratory conditions. The techniques of the cell culture have allowed scientists to use the cells in vitro for experimental studies, such as the production of vaccine, antibody and enzime, drug research, cell-cell interactions. Human umbilical vein endothelial cell is a good source for endothelial cell, because it is cheaper, easy to find and has the basic features of the normal endothelial cells.

  15. Trans fatty acids induce vascular inflammation and reduce vascular nitric oxide production in endothelial cells.

    Directory of Open Access Journals (Sweden)

    Naomi G Iwata

    Full Text Available Intake of trans fatty acids (TFA, which are consumed by eating foods made from partially hydrogenated vegetable oils, is associated with a higher risk of cardiovascular disease. This relation can be explained by many factors including TFA's negative effect on endothelial function and reduced nitric oxide (NO bioavailability. In this study we investigated the effects of three different TFA (2 common isomers of C18 found in partially hydrogenated vegetable oil and a C18 isomer found from ruminant-derived-dairy products and meat on endothelial NF-κB activation and nitric oxide (NO production. Human endothelial cells were treated with increasing concentrations of Elaidic (trans-C18:1 (9 trans, Linoelaidic (trans-C18:2 (9 trans, 12 trans, and Transvaccenic (trans-C18:1 (11 trans for 3 h. Both Elaidic and Linoelaidic acids were associated with increasing NF-κB activation as measured by IL-6 levels and phosphorylation of IκBα, and impairment of endothelial insulin signaling and NO production, whereas Transvaccenic acid was not associated with these responses. We also measured superoxide production, which has been hypothesized to be necessary in fatty acid-dependent activation of NF-κB. Both Elaidic acid and Linoelaidic acid are associated with increased superoxide production, whereas Transvaccenic acid (which did not induce inflammatory responses did not increase superoxide production. We observed differential activation of endothelial superoxide production, NF-κB activation, and reduction in NO production by different C18 isomers suggesting that the location and number of trans double bonds effect endothelial NF-κB activation.

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

    OpenAIRE

    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 eviden...

  17. Programmable insect cell carriers for systemic delivery of integrated cancer biotherapy.

    Science.gov (United States)

    Roy, D G; Power, A T; Bourgeois-Daigneault, M C; Falls, T; Ferreira, L; Stern, A; Tanese de Souza, C; McCart, J A; Stojdl, D F; Lichty, B D; Atkins, H; Auer, R C; Bell, J C; Le Boeuf, F

    2015-12-28

    Due to cancer's genetic complexity, significant advances in the treatment of metastatic disease will require sophisticated, multi-pronged therapeutic approaches. Here we demonstrate the utility of a Drosophila melanogaster cell platform for the production and in vivo delivery of multi-gene biotherapeutic systems. We show that cultured Drosophila S2 cell carriers can stably propagate oncolytic viral therapeutics that are highly cytotoxic for mammalian cancer cells without adverse effects on insect cell viability or gene expression. Drosophila cell carriers administered systemically to immunocompetent animals trafficked to tumors to deliver multiple biotherapeutics with little apparent off-target tissue homing or toxicity, resulting in a therapeutic effect. Cells of this Dipteran invertebrate provide a genetically tractable platform supporting the integration of complex, multi-gene biotherapies while avoiding many of the barriers to systemic administration of mammalian cell carriers. These transporters have immense therapeutic potential as they can be modified to express large banks of biotherapeutics with complementary activities that enhance anti-tumor activity. PMID:26482080

  18. A ginkgo biloba extract promotes proliferation of endogenous neural stem cells in vascular dementia rats

    Institute of Scientific and Technical Information of China (English)

    Jiwei Wang; Wen Chen; Yuliang Wang

    2013-01-01

    The ginkgo biloba extract EGb761 improves memory loss and cognitive impairments in patients with senile dementia. It also promotes proliferation of neural stem cells in the subventricular zone in Parkinson's disease model mice and in the hippocampal zone of young epileptic rats. However, it remains unclear whether EGb761 enhances proliferation of endogenous neural stem cells in the brain of rats with vascular dementia. In this study, a vascular dementia model was established by repeatedly clipping and reperfusing the bilateral common carotid arteries of rats in combination with an intraperitoneal injection of a sodium nitroprusside solution. Seven days after establishing the model, rats were intragastrically given EGb761 at 50 mg/kg per day. Learning and memory abilities were assessed using the Morris water maze and proliferation of endogenous neural stem cells in the subventricular zone and dentate gyrus were labeled by 5-bromo-2-deoxyuridine immunofluorescence in all rats at 15 days, and 1, 2, and 4 months after model establishment. The escape latencies in Morris water maze tests of rats with vascular dementia after EGb761 treatment were significantly shorter than the model group. Immunofluorescence staining showed that the number and proliferation of 5-bromo-2-deoxyuridine-positive cells in the subventricular zone and dentate gyrus of the EGb761-treated group were significantly higher than in the model group. These experimental findings suggest that EGb761 enhances proliferation of neural stem cells in the subventricular zone and dentate gyrus, and significantly improves learning and memory in rats with vascular dementia.

  19. Impaired SIRT1 promotes the migration of vascular smooth muscle cell-derived foam cells.

    Science.gov (United States)

    Zhang, Ming-Jie; Zhou, Yi; Chen, Lei; Wang, Xu; Pi, Yan; Long, Chun-Yan; Sun, Meng-Jiao; Chen, Xue; Gao, Chang-Yue; Li, Jing-Cheng; Zhang, Li-Li

    2016-07-01

    The formation of fat-laden foam cells, contributing to the fatty streaks of the plaques of atheroma, is the critical early process in atherosclerosis. The previous study demonstrated that vascular smooth muscle cells (VSMCs) contain a much larger burden of the excess cholesterol in comparison with monocyte-derived macrophages in human coronary atherosclerosis, as the main origin of foam cells. It is noteworthy that VSMC-derived foam cells are deposited in subintima but not media, where VSMCs normally deposit in. Therefore, migration from media to intima is an indispensable step for a VSMC to accrue neutral lipids and form foam cell. Whether this migration occurs paralleled with or prior to the formation of foam cell is still unclear. Herein, the present study was designed to test the VSMC migratory capability in the process of foam cell formation induced by oxidized low-density lipoprotein (oxLDL). In conclusion, we provide evidence that oxLDL induces the VSMC-derived foam cells formation with increased migration ability and MMP-9 expression, which were partly attributed to the impaired SIRT1 and enhanced nuclear factor-kappa B (NF-κB) activity. As activation of transient receptor potential vanilloid type 1 (TRPV1) has been reported to have anti-atherosclerotic effects, we investigated its role in oxLDL-treated VSMC migration. It is found that activating TRPV1 by capsaicin inhibits VSMC foam cell formation and the accompanied migration through rescuing the SIRT1 and suppressing NF-κB signaling. The present study provides evidence that SIRT1 may be a promising intervention target of atherosclerosis, and raises the prospect of TRPV1 in prevention and treatment of atherosclerosis. PMID:26883442

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

    Directory of Open Access Journals (Sweden)

    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.

  1. Electron-phonon energy transfer in hot-carrier solar cells

    OpenAIRE

    Luque López, Antonio; Martí Vega, Antonio

    2010-01-01

    Hot-carrier solar cells may yield very high efficiency if the heat transfer from electrons to phonons is low enough. In this paper we calculate this heat transfer for the two inelastic mechanisms known to limit the electric conductivity: the multi-valley scattering in non-polar semiconductors and the coupling of electrons to longitudinal optical phonons in polar semiconductors. Heat transfer is ruled by matrix elements deduced from electric conductivity measurements. The cell power extracted ...

  2. Ethanol production by Kluyveromyces lactis immobilized cells in copolymer carriers produced by radiation polymerization.

    Science.gov (United States)

    El-Batal, A I; Farahat, L M; El-Rehim, H A

    2000-01-01

    The conditions for batch and continuous production of ethanol, using immobilized growing yeast cells of Kluyveromyces lactis, have been optimized. Yeast cells have been immobilized in hydrogel copolymer carriers composed of polyvinyl alcohol (PVA) with various hydrophilic monomers, using radiation copolymerization technique. Yeast cells were immobilized through adhesion and multiplication of yeast cells themselves. The ethanol production of immobilized growing yeast cells with these hydrogel carriers was related to the monomer composition of the copolymers and the optimum monomer composition was hydroxyethyl methacrylate (HEMA). In this case by using batch fermentation, the superior ethanol production was 32.9 g L(-1) which was about 4 times higher than that of cells in free system. The relation between the activity of immobilized yeast cells and the water content of the copolymer carriers was also discussed. Immobilized growing yeast cells in PVA: HEMA (7%: 10%, w/w) hydrogel copolymer carrier, were used in a packed-bed column reactor for the continuous production of ethanol from lactose at different levels of concentrations (50, 100 and 150) g L(-1). For all lactose feed concentrations, an increase in dilution rates from 0.1 h(-1) to 0.3 h(-1) lowered ethanol concentration in fermented broth, but the volumetric ethanol productivity and volumetric lactose uptake rate were improved. The fermentation efficiency was lowered with the increase in dilution rate and also at higher lactose concentration in feed medium and a maximum of 70.2% was obtained at the lowest lactose concentration 50 g L(-1). PMID:11093678

  3. Experimental evidence of hot carriers solar cell operation in multi-quantum wells heterostructures

    Energy Technology Data Exchange (ETDEWEB)

    Rodière, Jean; Lombez, Laurent, E-mail: laurent.lombez@chimie-paristech.fr [IRDEP, Institute of R and D on Photovoltaic Energy, UMR 7174, CNRS-EDF-Chimie ParisTech, 6 Quai Watier-BP 49, 78401 Chatou Cedex (France); Le Corre, Alain; Durand, Olivier [INSA, FOTON-OHM, UMR 6082, F-35708 Rennes (France); Guillemoles, Jean-François [IRDEP, Institute of R and D on Photovoltaic Energy, UMR 7174, CNRS-EDF-Chimie ParisTech, 6 Quai Watier-BP 49, 78401 Chatou Cedex (France); NextPV, LIA CNRS-RCAST/U. Tokyo-U. Bordeaux, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8904 (Japan)

    2015-05-04

    We investigated a semiconductor heterostructure based on InGaAsP multi quantum wells (QWs) using optical characterizations and demonstrate its potential to work as a hot carrier cell absorber. By analyzing photoluminescence spectra, the quasi Fermi level splitting Δμ and the carrier temperature are quantitatively measured as a function of the excitation power. Moreover, both thermodynamics values are measured at the QWs and the barrier emission energy. High values of Δμ are found for both transition, and high carrier temperature values in the QWs. Remarkably, the quasi Fermi level splitting measured at the barrier energy exceeds the absorption threshold of the QWs. This indicates a working condition beyond the classical Shockley-Queisser limit.

  4. Extravillous trophoblast cells-derived exosomes promote Vascular Smooth Muscle Cell Migration

    Directory of Open Access Journals (Sweden)

    Carlos eSalomon

    2014-08-01

    Full Text Available Background: Vascular smooth muscle cells (VSMCs migration is a critical process during human uterine spiral artery (SpA remodeling and a successful pregnancy. Extravillous trophoblast cells (EVT interact with VSMC and enhance their migration, however, the mechanisms by which EVT remodel SpA remain to be fully elucidated. We hypothesize that exosomes released from EVT promote VSMC migration.Methods: JEG-3 and HTR-8/SVneo cell lines were used as models for EVT. Cells were cultured at 37 0C and humidified under an atmosphere of 5% CO2-balanced N2 to obtain 8% O2. Cell-conditioned media were collected and exosomes (exo-JEG-3 and exo- HTR-8/SVneo isolated by differential and buoyant density centrifugation. The effects of exo-EVT on VSMC migration were established using a real-time, live-cell imaging system (Incucyte™. Exosomal proteins where identified by mass spectrometry and submitted to bioinformatic pathway analysis (Ingenuity software .Results: HTR-8/SVneo cells were significantly more (~30% invasive than JEG-3 cells. HTR-8/SVneo cells released 2.6-fold more exosomes (6.39 x 108 ± 2.5 x108 particles/106 cells compared to JEG-3 (2.86 x 108 ± 0.78 x108 particles/106 cells. VSMC migration was significantly increased in the presence of exo-JEG-3 and exo-HTR-8/SVneo compared to control (-exosomes (21.83 ± 0.49 h and 15.57 ± 0.32, respectively, versus control 25.09 ± 0.58 h, p<0.05. Sonication completely abolished the effect of exosomes on VSMC migration. Finally, mass spectrometry analysis identified unique exosomal proteins for each EVT cell line-derived exosomes.Conclusion: The data obtained in this study are consistent with the hypothesis that the release, content and bioactivity of exosomes derived from EVT-like cell lines is cell origin-dependent and differentially regulates VSMC migration. Thus, an EVT exosomal signaling pathway may contribute to SpA remodeling by promoting the migration of VSMC out of the vessel walls.

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

    Science.gov (United States)

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

    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. PMID:27127049

  6. Vascular smooth muscle cells in cultures on low density polyethylene modified with plasma discharge and biofunctionalization

    Czech Academy of Sciences Publication Activity Database

    Pařízek, Martin; Kasálková, N.; Bačáková, Lucie; Kolářová, K.; Lisá, Věra; Švorčík, V.

    2009-01-01

    Roč. 12, 89-91 (2009), s. 25-28. ISSN 1429-7248 R&D Projects: GA AV ČR(CZ) KAN400480701; GA AV ČR(CZ) 1QS500110564 Institutional research plan: CEZ:AV0Z50110509 Keywords : Ar plasma discharge * low density polyethylene * vascular smooth muscle cells Subject RIV: EI - Biotechnology ; Bionics

  7. Modulation of stem cell differentiation by the influence of nanobiomaterials/carriers.

    Science.gov (United States)

    Bokara, Kiran Kumar; Oggu, Gopi Suresh; Vidyasagar, Aditya Josyula; Asthana, Amit; Lee, Jong Eun; Rao, Ch Mohan

    2014-01-01

    Stem cells, either neural [NSCs] or mesenchymal [MSCs], possess tremendous untapped potential for cell therapy. Unlike the NSCs, MSCs are multi-potent and they have high self-renewal capability and broad tissue distribution. Since they do not produce significant immune rejection on post-transplantation; they are better suited for cell-based therapies. However, several critical issues need to be addressed to maximize stem cell-derived therapeutic effects. The key factor affecting the therapeutic application of stem cells is exposure to hostile conditions in vivo such as oxidative stress, which results in considerably low survival rate of these cells at transplanted sites, thereby reducing the therapeutic efficiency. Such limitation has led scientists to design clinically relevant, innovative and multifaceted solutions including the use of nanobiomaterials. Use of cytocompatible nanobiomaterials holds great promise and has gained attention of researchers, worldwide. Various nanobiomaterials are being explored to increase the survival efficiency and direct differentiation of stem cells to generate tissue-specific cells for biomedical research and futuristic therapies. These materials have superior cytocompatability, mechanical, electrical, optical, catalytic and magnetic properties. Non-invasive visualization of the biological system has been developed using magnetic nanoparticles and magnetic resonance imaging [MRI] approaches. Apart from viral vectors, non-viral carriers such as DNA nano carriers, single stranded RNA nanoparticles, liposomes and carbon nanotubes/wires are being exploited for gene delivery into stem cells. This article reviews potential application of various biocompatible nanomaterials in stem cell research and development. PMID:25163795

  8. Efficient, non-toxic anion transport by synthetic carriers in cells and epithelia

    Science.gov (United States)

    Li, Hongyu; Valkenier, Hennie; Judd, Luke W.; Brotherhood, Peter R.; Hussain, Sabir; Cooper, James A.; Jurček, Ondřej; Sparkes, Hazel A.; Sheppard, David N.; Davis, Anthony P.

    2016-01-01

    Transmembrane anion transporters (anionophores) have potential for new modes of biological activity, including therapeutic applications. In particular they might replace the activity of defective anion channels in conditions such as cystic fibrosis. However, data on the biological effects of anionophores are scarce, and it remains uncertain whether such molecules are fundamentally toxic. Here, we report a biological study of an extensive series of powerful anion carriers. Fifteen anionophores were assayed in single cells by monitoring anion transport in real time through fluorescence emission from halide-sensitive yellow fluorescent protein. A bis-(p-nitrophenyl)ureidodecalin shows especially promising activity, including deliverability, potency and persistence. Electrophysiological tests show strong effects in epithelia, close to those of natural anion channels. Toxicity assays yield negative results in three cell lines, suggesting that promotion of anion transport may not be deleterious to cells. We therefore conclude that synthetic anion carriers are realistic candidates for further investigation as treatments for cystic fibrosis.

  9. Relationships between systemic vascular resistance, blood rheology and nitric oxide in children with sickle cell anemia or sickle cell-hemoglobin C disease. : Hemodynamics in sickle cell disease

    OpenAIRE

    Lamarre, Yann; Hardy-Dessources, Marie-Dominique; Romana, Marc; Lalanne-Mistrih, Marie-Laure; Waltz, Xavier; Petras, Marie; Doumdo, Lydia; Blanchet-Deverly, Anne; Martino, Jean; Tressières, Benoît; Maillard, Frederic; Tarer, Vanessa; Etienne-Julan, Maryse; Connes, Philippe

    2013-01-01

    Vascular function has been found to be impaired in patients with sickle cell disease (SCD). The present study investigated the determinants of systemic vascular resistance in two main SCD syndromes in children: sickle cell anemia (SCA) and sickle cell-hemoglobin C disease (SCC). Nitric oxide metabolites (NOx), hematological, hemorheological, and hemodynamical parameters were investigated in 61 children with SCA and 49 children with SCC. While mean arterial pressure was not different between S...

  10. 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.

  11. Charge Carrier Conduction Mechanism in PbS Quantum Dot Solar Cells: Electrochemical Impedance Spectroscopy Study.

    Science.gov (United States)

    Wang, Haowei; Wang, Yishan; He, Bo; Li, Weile; Sulaman, Muhammad; Xu, Junfeng; Yang, Shengyi; Tang, Yi; Zou, Bingsuo

    2016-07-20

    With its properties of bandgap tunability, low cost, and substrate compatibility, colloidal quantum dots (CQDs) are becoming promising materials for optoelectronic applications. Additionally, solution-processed organic, inorganic, and hybrid ligand-exchange technologies have been widely used in PbS CQDs solar cells, and currently the maximum certified power conversion efficiency of 9.9% has been reported by passivation treatment of molecular iodine. Presently, there are still some challenges, and the basic physical mechanism of charge carriers in CQDs-based solar cells is not clear. Electrochemical impedance spectroscopy is a monitoring technology for current by changing the frequency of applied alternating current voltage, and it provides an insight into its electrical properties that cannot be measured by direct current testing facilities. In this work, we used EIS to analyze the recombination resistance, carrier lifetime, capacitance, and conductivity of two typical PbS CQD solar cells Au/PbS-TBAl/ZnO/ITO and Au/PbS-EDT/PbS-TBAl/ZnO/ITO, in this way, to better understand the charge carriers conduction mechanism behind in PbS CQD solar cells, and it provides a guide to design high-performance quantum-dots solar cells. PMID:27176547

  12. Ancestral vascular lumen formation via basal cell surfaces

    OpenAIRE

    Tomás Kucera; Boris Strilić; Kathrin Regener; Michael Schubert; Vincent Laudet; Eckhard Lammert

    2015-01-01

    The cardiovascular system of bilaterians developed from a common ancestor. However, no endothelial cells exist in invertebrates demonstrating that primitive cardiovascular tubes do not require this vertebrate-specific cell type in order to form. This raises the question of how cardiovascular tubes form in invertebrates? Here we discovered that in the invertebrate cephalochordate amphioxus, the basement membranes of endoderm and mesoderm line the lumen of the major vessels, namely aorta and he...

  13. Vascular effects of multiwalled carbon nanotubes in dyslipidemic ApoE-/- mice and cultured endothelial cells

    DEFF Research Database (Denmark)

    Cao, Yi; Jacobsen, Nicklas Raun; Danielsen, Pernille Høgh;

    2014-01-01

    Accumulating evidences indicate that pulmonary exposure to carbon nanotubes (CNTs) is associated with increased risk of lung diseases, whereas the effect on the vascular system is less studied. We investigated vascular effects of 2 types of multiwalled CNTs (MWCNTs) in apolipoprotein E(-/-) mice......, wild-type mice, and cultured cells. The ApoE(-/-) mice had accelerated plaque progression in aorta after 5 intracheal instillations of MWCNT (25.6 μg/mouse weekly for 5 weeks). The exposure was associated with pulmonary inflammation, lipid peroxidation, and increased expression of inflammatory......, oxidative stress, DNA repair, and vascular activation response genes. The level of oxidatively damaged DNA in lung tissue was unaltered, probably due to increased DNA repair capacities. Despite upregulation of inflammatory genes in the liver, effects on systemic cytokines and lipid peroxidation were minimal...

  14. Ascorbic acid improves embryonic cardiomyoblast cell survival and promotes vascularization in potential myocardial grafts in vivo

    OpenAIRE

    Martinez, E. C.; Wang, J; Gan, S U; Singh, R.; Lee, C. N.; Kofidis, T

    2010-01-01

    Organ restoration via cell therapy and tissue transplantation is limited by impaired graft survival. We tested the hypothesis that ascorbic acid (AA) reduces cell death in myocardial grafts both in vitro and in vivo and introduced a new model of autologous graft vascularization for later transplantation. Luciferase (Fluc)- and green fluorescent protein (GFP)-expressing H9C2 cardiomyoblasts were seeded in gelatin scaffolds to form myocardial artificial grafts (MAGs). MAGs were supplemented wit...

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

    International Nuclear Information System (INIS)

    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

  16. Adipose-derived Stromal Cells Overexpressing Vascular Endothelial Growth Factor Accelerate Mouse Excisional Wound Healing

    OpenAIRE

    Nauta, Allison; Seidel, Catharina; Deveza, Lorenzo; Montoro, Daniel; Grova, Monica; Ko, Sae Hee; Hyun, Jeong; Geoffrey C Gurtner; Longaker, Michael T.; Yang, Fan

    2012-01-01

    Angiogenesis is essential to wound repair, and vascular endothelial growth factor (VEGF) is a potent factor to stimulate angiogenesis. Here, we examine the potential of VEGF-overexpressing adipose-derived stromal cells (ASCs) for accelerating wound healing using nonviral, biodegradable polymeric vectors. Mouse ASCs were transfected with DNA plasmid encoding VEGF or green fluorescent protein (GFP) using biodegradable poly (β-amino) esters (PBAE). Cells transfected using Lipofectamine 2000, a c...

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

    OpenAIRE

    Zhao, Jingshan; Niu, Honglin; Li, Aiying; Nie, Lei

    2016-01-01

    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 pho...

  18. Doxycycline Alters Vascular Smooth Muscle Cell Adhesion, Migration, and Reorganization of Fibrillar Collagen Matrices

    OpenAIRE

    Franco, Christopher; Ho, Bernard; Mulholland, Diane; Hou, Guangpei; Islam, Muzharul; Donaldson, Katey; Bendeck, Michelle Patricia

    2006-01-01

    Remodeling of injured blood vessels is dependent on smooth muscle cells and matrix metalloproteinase activity. Doxycycline is a broad spectrum matrix metalloproteinase inhibitor that is under investigation for the treatment of acute coronary syndromes and aneurysms. In the present study, we examine the mechanisms by which doxycycline inhibits smooth muscle cell responses using a series of in vitro assays that mimic critical steps in pathological vascular remodeling. Doxycycline treatment dram...

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

    Directory of Open Access Journals (Sweden)

    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.

  20. Increased expression of osteoprotegerin in vascular smooth muscle cells from spontaneously hypertensive rats

    Institute of Scientific and Technical Information of China (English)

    Yongshan MOU; Tianhua LEI; Luning ZHAO; Xiaojun ZHU; Mingui FU; Yuqing E CHEN

    2004-01-01

    Background Osteoprotegerin (OPG) is a secreted protein of the tumor necrosis factor receptor family, which regulates bone mass by inhibiting osteoclast differentiation and activation. Although OPG is expressed ubiquitously and abundantly in many tissues and cell types including vascular cells, the role of OPG in other tissues is unknown.Our previous studies demonstrated that OPG was highly expressed in vascular smooth muscle cells (VSMC) and upregulated during vascular lesion formation. Methods and Results We documented, by Northern blot analysis,that the expression of OPG was more prevalent in the aorta and cultured VSMC from spontaneously hypertensive rats (SI-IR) compared to Wistar-Kyoto rats (WKY). In addition, we found that the expression of Angiotensin II (Ang II)type I receptor (AT1R) in SHR VSMC was at significantly increased levels than in WKY VSMC. Furthermore, Ang II potently induced the expression of OPG in VSMC in a time- and dose-dependent manner through the AT1R signaling pathway. Conclusions OPG expression was substantially greater in SHR VSMC, suggesting that OPG may be an important determinant of vascular remodeling in SHR.

  1. Engineering micropatterned surfaces to modulate the function of vascular stem cells

    International Nuclear Information System (INIS)

    Highlights: • We examine vascular stem cell function on microgrooved and micropost patterned polymer substrates. • 10 μm microgrooved surfaces significantly lower VSC proliferation but do not modulate calcified matrix deposition. • Micropost surfaces significantly lower VSC proliferation and decrease calcified matrix deposition. - Abstract: Multipotent vascular stem cells have been implicated in vascular disease and in tissue remodeling post therapeutic intervention. Hyper-proliferation and calcified extracellular matrix deposition of VSC cause blood vessel narrowing and plaque hardening thereby increasing the risk of myocardial infarct. In this study, to optimize the surface design of vascular implants, we determined whether micropatterned polymer surfaces can modulate VSC differentiation and calcified matrix deposition. Undifferentiated rat VSC were cultured on microgrooved surfaces of varied groove widths, and on micropost surfaces. 10 μm microgrooved surfaces elongated VSC and decreased cell proliferation. However, microgrooved surfaces did not attenuate calcified extracellular matrix deposition by VSC cultured in osteogenic media conditions. In contrast, VSC cultured on micropost surfaces assumed a dendritic morphology, were significantly less proliferative, and deposited minimal calcified extracellular matrix. These results have significant implications for optimizing the design of cardiovascular implant surfaces

  2. Effects of vascular endothelial growth factor on angiogenesis of the endothelial cells isolated from cavernous malformations

    Institute of Scientific and Technical Information of China (English)

    TAN YuZhen; ZHAO Yao; WANG HaiJie; ZHOU LiangFu; MAO Ying; LIU Rui; SHU Jia; WANG YongFei

    2008-01-01

    Human cerebral cavernous malformation (CM) is a common vascular malformation of the central nervous system. We have investigated the biological characteristics of CM endothelial cells and the cellular and molecular mechanisms of CM angiogenesis to offer new insights into exploring effective measures for treatment of this disease. The endothelial cells were isolated from CM tissue masses dissected during operation and expanded in vitro. Expression of VEGFR-1 and VEGFR-2 was examined with immunocytochemical staining. Proliferation, migration and tube formation of CM endothelial cells were determined using MTT, wounding and transmigration assays, and three-dimensional collagen type Ⅰ gel respectively. The endothelial cells were successfully isolated from the tissue specimens of 25 CMs dissected without dipolar electrocoagulation. The cells show the general characteristics of the vascular endothelial cells. Expression of VEGFR-1 and VEGFR-2 on the cells is higher than that on the normal cerebral microvascular endothelial cells. After treatment with VEGF, numbers of the proliferated and migrated cells, the maximal distance of cell migration and the length and area of capillary-like struc-tures formed in the three-dimensional collagen gel increase significantly. These results demonstrate that expression of VEGFR-1 and VEGFR-2 on CM endothelial cells is up-regulated. By binding to re-ceptors, VEGF may activate the downstream signaling pathways and promote proliferation, migration and tube formation of CM endothelial cells. VEGF/VEGFR signaling pathways play important regulating roles in CM angiogenesis.

  3. βA3/A1-crystallin in astroglial cells regulates retinal vascular remodeling during development

    Science.gov (United States)

    Sinha, Debasish; Klise, Andrew; Sergeev, Yuri; Hose, Stacey; Bhutto, Imran A.; Hackler, Laszlo; Malpic-llanos, Tanya; Samtani, Sonia; Grebe, Rhonda; Goldberg, Morton F.; Hejtmancik, J. Fielding; Nath, Avindra; Zack, Donald J.; Fariss, Robert N.; McLeod, D. Scott; Sundin, Olof; Broman, Karl W.; Lutty, Gerard A.; Zigler, J. Samuel

    2016-01-01

    Vascular remodeling is a complex process critical to development of the mature vascular system. Astrocytes are known to be indispensable for initial formation of the retinal vasculature; our studies with the Nuc1 rat provide novel evidence that these cells are also essential in the retinal vascular remodeling process. Nuc1 is a spontaneous mutation in the Sprague–Dawley rat originally characterized by nuclear cataracts in the heterozygote and microphthalmia in the homozygote. We report here that the Nuc1 allele results from mutation of the βA3/A1-crystallin gene, which in the neural retina is expressed only in astrocytes. We demonstrate striking structural abnormalities in Nuc1 astrocytes with profound effects on the organization of intermediate filaments. While vessels form in the Nuc1 retina, the subsequent remodeling process required to provide a mature vascular network is deficient. Our data implicate βA3/A1-crystallin as an important regulatory factor mediating vascular patterning and remodeling in the retina. PMID:17931883

  4. Hypertonic upregulation of amino acid transport system A in vascular smooth muscle cells.

    Science.gov (United States)

    Chen, J G; Klus, L R; Steenbergen, D K; Kempson, S A

    1994-08-01

    The A10 line of vascular smooth muscle cells has Na+ dependent transport systems for alanine, proline, and Pi, whereas uptake of leucine, myo-inositol and D-glucose is Na+ independent. When A10 cells were incubated for 4 h in medium made hypertonic by addition of sucrose, there was a marked increase in Na(+)-dependent transport of alanine and proline but no change in Na(+)-dependent Pi uptake or Na(+)-independent uptake of leucine and inositol. Intracellular alanine content was increased 61% by the hypertonic treatment. Other nonpenetrating solutes, such as cellobiose and mannitol, reproduced the effect of sucrose, but urea, a penetrating solute, did not. Studies with 2-(methylamino)-isobutyric acid revealed that the upregulation by hypertonicity involved only system A. Increases in alanine and proline uptake also occurred after incubating the cells in isotonic medium containing 0.1 mM ouabain, suggesting that an increase in intracellular Na+ may be part of the intracellular signal for upregulation of system A. Hypertonic upregulation of Na(+)-dependent alanine transport occurred also in primary cultures of vascular smooth muscle cells. The response was blocked by actinomycin D and cycloheximide, indicating that gene transcription and protein synthesis play important roles in the mechanism leading to increased alanine uptake. We conclude that vascular smooth muscle cells, during prolonged hypertonic stress, activate system A and accumulate specific neutral amino acids which may act as organic osmolytes to help maintain normal cell volume. PMID:8074188

  5. 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.

  6. Glycoproteomic characterization of carriers of the CD15/Lewisx epitope on Hodgkin's Reed-Sternberg cells

    Directory of Open Access Journals (Sweden)

    Hitchen Paul G

    2011-03-01

    Full Text Available Abstract Background The Lewisx trisaccharide, also referred to as the CD15 antigen, is a diagnostic marker used to distinguish Hodgkin's lymphoma from other lymphocytic cancers. However, the role of such fucosylated structures remains poorly understood, in part because carriers of Lewisx structures on Hodgkin's Reed-Sternberg cells have not been identified. Methods GalMBP, an engineered carbohydrate-recognition protein that binds selectively to oligosaccharides with paired terminal galactose and fucose residues, has been used in conjunction with proteomic and glycomic analysis to identify glycoprotein carriers of Lewisx and related glycan structures in multiple Hodgkin's Reed-Sternberg cell lines. Results Multiple glycoproteins that bind to GalMBP and carry CD15/Lewisx have been identified in a panel of six Reed-Sternberg cell lines. The most commonly identified Lewisx-bearing glycoproteins are CD98hc, which was found in all six cell lines tested, and intercellular adhesion molecule-1 and DEC-205, which were detected in five and four of the lines, respectively. Thus, several of the most prominent cell adhesion molecules on the lymphomas carry this characteristic glycan epitope. In addition, the Hodgkin's Reed-Sternberg cell lines can be grouped into subsets based on the presence or absence of less common Lewisx-bearing glycoproteins. Conclusions CD98 and intercellular adhesion molecule-1 are major carriers of CD15/Lewisx on Reed-Sternberg cells. Binding of DC-SIGN and other glycan-specific receptors to the Lewisx epitopes on CD98 and intercellular adhesion molecule-1 may facilitate interaction of the lymphoma cells with lymphocytes and myeloid cells in lymph nodes.

  7. Invasion of Porphyromonas gingivalis strains into vascular cells and tissue

    Directory of Open Access Journals (Sweden)

    Ingar Olsen

    2015-08-01

    Full Text Available Porphyromonas gingivalis is considered a major pathogen in adult periodontitis and is also associated with multiple systemic diseases, for example, cardiovascular diseases. One of its most important virulence factors is invasion of host cells. The invasion process includes attachment, entry/internalization, trafficking, persistence, and exit. The present review discusses these processes related to P. gingivalis in cardiovascular cells and tissue. Although most P. gingivalis strains invade, the invasion capacity of strains and the mechanisms of invasion including intracellular trafficking among them differ. This is consistent with the fact that there are significant differences in the pathogenicity of P. gingivalis strains. P. gingivalis invasion mechanisms are also dependent on types of host cells. Although much is known about the invasion process of P. gingivalis, we still have little knowledge of its exit mechanisms. Nevertheless, it is intriguing that P. gingivalis can remain viable in human cardiovascular cells and atherosclerotic plaque and later exit and re-enter previously uninfected host cells.

  8. CD4+ mononuclear cells induce cytokine expression, vascular smooth muscle cell proliferation, and arterial occlusion after endothelial injury.

    OpenAIRE

    Hancock, W. W.; Adams, D. H.; Wyner, L R; Sayegh, M H; Karnovsky, M. J.

    1994-01-01

    Studies of T cell-deficient or immunosuppressed animals undergoing arterial endothelial denudation have yielded conflicting results as to the contribution of the immune system to neointimal vascular smooth muscle cell accumulation and proliferation. We investigated the cell types and cytokine expression associated with intimal hyperplasia occurring 14 days after balloon angioplasty of the carotid artery in Sprague-Dawley rats. Immunohistological studies using monoclonal antibodies showed that...

  9. Impaired Peroxisome Proliferator-activated Receptor-γ Contributes to Phenotypic Modulation of Vascular Smooth Muscle Cells during Hypertension*

    OpenAIRE

    Zhang, Lili; Xie, Peng; Wang, Jingzhou; Yang, Qingwu; Fang, Chuanqin; Zhou, Shuang; Li, Jingcheng

    2010-01-01

    The phenotypic modulation of vascular smooth muscle cells (VSMCs) plays a pivotal role in hypertension-induced vascular changes including vascular remodeling. The precise mechanisms underlying VSMC phenotypic modulation remain elusive. Here we test the role of peroxisome proliferator-activated receptor (PPAR)-γ in the VSMC phenotypic modulation during hypertension. Both spontaneously hypertensive rat (SHR) aortas and SHR-derived VSMCs exhibited reduced PPAR-γ expression and excessive VSMC phe...

  10. In vivo ectopic bone formation by devitalized mineralized stem cell carriers produced under mineralizing culture condition.

    Science.gov (United States)

    Chai, Yoke Chin; Geris, Liesbet; Bolander, Johanna; Pyka, Grzegorz; Van Bael, Simon; Luyten, Frank P; Schrooten, Jan

    2014-12-01

    Functionalization of tissue engineering scaffolds with in vitro-generated bone-like extracellular matrix (ECM) represents an effective biomimetic approach to promote osteogenic differentiation of stem cells in vitro. However, the bone-forming capacity of these constructs (seeded with or without cells) is so far not apparent. In this study, we aimed at developing a mineralizing culture condition to biofunctionalize three-dimensional (3D) porous scaffolds with highly mineralized ECM in order to produce devitalized, osteoinductive mineralized carriers for human periosteal-derived progenitors (hPDCs). For this, three medium formulations [i.e., growth medium only (BM1), with ascorbic acid (BM2), and with ascorbic acid and dexamethasone (BM3)] supplemented with calcium (Ca(2+)) and phosphate (PO4 (3-)) ions simultaneously as mineralizing source were investigated. The results showed that, besides the significant impacts on enhancing cell proliferation (the highest in BM3 condition), the formulated mineralizing media differentially regulated the osteochondro-related gene markers in a medium-dependent manner (e.g., significant upregulation of BMP2, bone sialoprotein, osteocalcin, and Wnt5a in BM2 condition). This has resulted in distinguished cell populations that were identifiable by specific gene signatures as demonstrated by the principle component analysis. Through devitalization, mineralized carriers with apatite crystal structures unique to each medium condition (by X-ray diffraction and SEM analysis) were obtained. Quantitatively, BM3 condition produced carriers with the highest mineral and collagen contents as well as human-specific VEGF proteins, followed by BM2 and BM1 conditions. Encouragingly, all mineralized carriers (after reseeded with hPDCs) induced bone formation after 8 weeks of subcutaneous implantation in nude mice models, with BM2-carriers inducing the highest bone volume, and the lowest in the BM3 condition (as quantitated by nano-computed tomography

  11. Immobilization of Escherichia coli cells with penicillin-amidohydrolase activity on solid polymeric carriers.

    Science.gov (United States)

    Zurková, E; Drobník, J; Kálal, J; Svec, F; Tyrácková, V; Vojtísek, V; Zeman, R

    1983-09-01

    Whole cells of Escherichia coli containing the enzyme penicillinamidohydrolase EC 3.5.1.11 were immobilized on the surface of modified macroporous copolymers of glycidylmethacrylate with ethylenedimethacrylate and of copolymers of methacrylaldehyde (MA) with divinylbenzene (DVB) by means of glutaraldehyde. These polymeric carriers were modified before cell binding by using ammonia or polyamines, especially ethylenediamine and hexamethylenediamine (HMDA). The highest specific activity and the largest yield in cell immobilization were achieved with the macroporous copolymer of MA and DVB modified with HMDA. The material thus obtained was used in repeated conversions of benzylpenicillin to 6-aminopenicillanic acid in a stirred batch reactor. PMID:18574818

  12. The Use of Fiber-Reinforced Scaffolds Cocultured with Schwann Cells and Vascular Endothelial Cells to Repair Rabbit Sciatic Nerve Defect with Vascularization

    Directory of Open Access Journals (Sweden)

    Hongyang Gao

    2013-01-01

    Full Text Available To explore the feasibility of biodegradable fiber-reinforced 3D scaffolds with satisfactory mechanical properties for the repair of long-distance sciatic nerve defect in rabbits and effects of vascularized graft in early stage on the recovery of neurological function, Schwann cells and vascular endothelial cells were cocultured in the fiber-reinforced 3D scaffolds. Experiment group which used prevascularized nerve complex for the repair of sciatic nerve defect and control group which only cultured with Schwann cells were set. The animals in both groups underwent electromyography to show the status of the neurological function recovery at 4, 8, and 16 weeks after the surgery. Sciatic nerve regeneration and myelination were observed under the light microscope and electron microscope. Myelin sheath thickness, axonal diameter, and number of myelinated nerve fiber were quantitatively analyzed using image analysis system. The recovery of foot ulcer, the velocity of nerve conduction, the number of regenerating nerve fiber, and the recovery of ultrastructure were increased in the experimental group than those in the control group. Prevascularized tissue engineered fiber-reinforced 3D scaffolds for the repair of sciatic nerve defects in rabbits can effectively promote the recovery of neurological function.

  13. The use of fiber-reinforced scaffolds cocultured with Schwann cells and vascular endothelial cells to repair rabbit sciatic nerve defect with vascularization.

    Science.gov (United States)

    Gao, Hongyang; You, Yang; Zhang, Guoping; Zhao, Feng; Sha, Ziyi; Shen, Yong

    2013-01-01

    To explore the feasibility of biodegradable fiber-reinforced 3D scaffolds with satisfactory mechanical properties for the repair of long-distance sciatic nerve defect in rabbits and effects of vascularized graft in early stage on the recovery of neurological function, Schwann cells and vascular endothelial cells were cocultured in the fiber-reinforced 3D scaffolds. Experiment group which used prevascularized nerve complex for the repair of sciatic nerve defect and control group which only cultured with Schwann cells were set. The animals in both groups underwent electromyography to show the status of the neurological function recovery at 4, 8, and 16 weeks after the surgery. Sciatic nerve regeneration and myelination were observed under the light microscope and electron microscope. Myelin sheath thickness, axonal diameter, and number of myelinated nerve fiber were quantitatively analyzed using image analysis system. The recovery of foot ulcer, the velocity of nerve conduction, the number of regenerating nerve fiber, and the recovery of ultrastructure were increased in the experimental group than those in the control group. Prevascularized tissue engineered fiber-reinforced 3D scaffolds for the repair of sciatic nerve defects in rabbits can effectively promote the recovery of neurological function. PMID:24490158

  14. VITALITY AND MORPHOLOGY OF TUMOR CELLS TREATED WITH 4-TIAZOLIDINONE DERIVATIVES IMMOBILIZED ON NANOSCALE POLYMER CARRIER

    Directory of Open Access Journals (Sweden)

    N. M. Boiko

    2015-02-01

    Full Text Available A nanoscale polymeric carrier was used for delivery of novel anticancer compounds – 4-tiazolidinone derivatives – to tumor cells of different lines. It was found that such way of delivery of the above mentioned compounds to target cells significantly (approximately 10 times decreased acting cytotoxic dose of some of these compounds with preservation of similar level of their antineoplastic effect in vitro towards various mammalian tumor cells. The microscopic investigation of these cells demonstrated that under the action of some immobilized 4-tiazolidonone derivatives, there was an increase (up to 40% of the part of apoptotic cells, as well as an appearance of 10% of cells with morphologically changed nucleus, and up to 35% of cells with an increased intensity of red fluorescence of acridine orange in the lysosomes, compared with such indicators observed under the action of free form of those compounds. Thus, the applied nanoscale carrier is a perspective polymer system for delivery of anticancer drugs to target cells.

  15. Effects of Gingko biloba extract (EGb 761) on vascular smooth muscle cell calcification induced by β-glycerophosphate.

    Science.gov (United States)

    Li, En-Gang; Tian, Jun; Xu, Zhong-Hua

    2016-05-01

    Objective To investigate the effects of Gingko biloba extract (EGb 761) on calcification induced by β-glycerophosphate in rat aortic vascular smooth muscle cells. Methods Rat aortic vascular smooth muscle cells were cultured with various concentrations of EGb 761 and β-glycerophosphate for 7 days. Calcium content in the cells, alkaline phosphatase activity, cell protein content, NF-κB activation, and reactive oxygen species production were assayed, respectively. Results The calcium depositions of vascular smooth muscle cells of the β-glycerophosphate group were significantly higher than those of the control group (p < 0.01), and were inhibited by EGb 761 in a concentration-dependent manner (p < 0.05). Data showed β-glycerophosphate induced the enhanced expression of alkaline phosphatase, up-regulated the NF-κB activity and increased reactive oxygen species production of vascular smooth muscle cells while these decreased when administrated with EGb 761(p < 0.05). Conclusions EGb 761 significantly reduced deposition of calcium induced by β-glycerophosphate in rat aortic vascular smooth muscle cells. It not only reduced the deposition of calcium, but also inhibited osteogenic transdifferentiation, which may be associated with decreasing expression of alkaline phosphatase, down-regulating the NF-κB activity, and reducing reactive oxygen species production of vascular smooth muscle cells, and may have the potential to serve as a role for vascular calcification in clinical situations. PMID:26908182

  16. A new image of the hematopoietic stem cell vascular niche

    OpenAIRE

    Silberstein, Leslie E.; Lin, Charles P.

    2013-01-01

    The microenvironment within the bone marrow that maintains hematopoietic stem cell (HSC) quiescence is the subject of intense study. In a recent Nature paper, Kunisaki et al combine imaging techniques and computational modeling to define a novel arteriolar niche for quiescent HSCs within the bone marrow.

  17. Succinobucol induces apoptosis in vascular smooth muscle cells

    Czech Academy of Sciences Publication Activity Database

    Midwinter, R.G.; Maghzal, G.; Dennis, J.M.; Wu, B.J.; Cai, H.; Kapralov, A.A.; Belikova, N.A.; Tyurina, Y.Y.; Dong, L. F.; Khachigian, L.; Neužil, Jiří; Kagan, V.E.; Stocker, R.

    2012-01-01

    Roč. 52, č. 5 (2012), s. 871-879. ISSN 0891-5849 R&D Projects: GA ČR(CZ) GAP301/10/1937 Institutional research plan: CEZ:AV0Z50520701 Keywords : reactive oxygen species * free radicals * apoptosis Subject RIV: EA - Cell Biology Impact factor: 5.271, year: 2012

  18. Higher Levels of Adiponectin in Vascular Endothelial Cells are Associated with Greater Brachial Artery Flow-mediated Dilation in Older Adults

    OpenAIRE

    Yoo, Jeung-Ki; Hwang, Moon-Hyon; Luttrell, Meredith J.; Kim, Han-Kyul; Meade, Thomas H.; English, Mark; Segal, Mark S.; Christou, Demetra D.

    2015-01-01

    Adiponectin, an adipocyte-derived protein, exerts anti-atherosclerotic effects on the vascular endothelium. Recently adiponectin protein has been reported in murine vascular endothelial cells, however, whether adiponectin is present in human vascular endothelial cells remains unexplored. We sought to examine 1) adiponectin protein in vascular endothelial cells collected from older adults free of overt cardiovascular disease; 2) the relation between endothelial cell adiponectin and in vivo vas...

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

    International Nuclear Information System (INIS)

    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 125I-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 [3H]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

  20. Vascular remodeling and mobilization of bone marrow-derived cells in cuff-induced vascular injury in LDL receptor knockout muce

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Background Vascular remodeling is an important pathologic process in vascular injury for various vascular disorders such as atherosclerosis,postangioplasty restenosis and transplant arteriopathy.Recently,pathologic change and the role of bone marrow derived cells were wildly studied in atherosclerosis and restenosis.But the manner of lesion formation in neointima and cell recruitment in vascular remodeling lesion in the present of hypercholesterolemia is not Vet fully understood. Methods Double-transgenic mice knockout of LDL receptor gene (LDL-/-) and expressing ubiquitously green fluorescent protein (GFP) were obtained by cross-breeding LDL-/-mice with the GFP-expressing transgenic mice. LDL-/- mice (22-24 weeks of age) fed high fat diet containing 1.25% (w/w) cholesterol were subjected to 9Gy irradiation and received bone marrow (BM) cells from the double-transgenic mice.Four weeks later,a nonconstrictive cuff was Dlaced around the right femoral artery.After another 2 weeks,both right and left femoral arteries were harvested and subjected to histochemical analysis.Apoptosis was analyzed in situ using TUNEL assay.Resuits Two weeks after cuff placement,atherosclerotic lesions developed in the intima consisting of a massive accumulation of foam cells, The tissue stained with anti-α smooth muscle actin (SMA) antibody,showed a number of SMA-positive cells in the intimal lesion area.They were also positive for GFP,indicating that BM-derived cells can differentiate to SMCs in the intima in cuff-induced vascular remodeling lesions.Numerous small vessels in the adventitia as well as the endothelial lining of the intima were positive both for CD31 and GFP.The intima and media showed a larae number of TUNEL-positive signals after 2 weeks cuff injury,indicating the presence of apoptosis in vascular remodelina.Conclusions Atherosclerotic lesions in mice can be developed in the intima after 2 weeks of cuff-induced vascular inJury under the hypercholesterolemic conditions

  1. Effects of Panax notoginseng saponins on vascular endothelial cells in vitro

    Institute of Scientific and Technical Information of China (English)

    關超然; 關加荤

    2000-01-01

    AIM: To investigate the inhibition of endothelium-dependent in vitro vascular relaxation induced by the total saponins (gensenosides) from Panax notoginseng ( PNS ) and the effect of PNS on the cytosolic Ca2 + concentration on cultured bovine pulmonary artery endothelial cells.METHODS: The endothelial-dependent vascular relaxation was assessed using acetylcholine (ACh) or cyclopiazonic acid (CPA) induced relaxation in endothelium-intact rat aorta. Cytosolic Caa + level was assessed in real time using dynamic digital fluorescence ratio imaging.RESULTS: In addition to its direct relaxation of the smooth muscle cells at high concentrations, PNS, at 100 mg/L having little effect on smooth muscle, caused a marked inhibition of endothelium-dependent relaxation brought about by PNS. This inhibitory effect was due to its inhibition of elevation of cytosolic Ca2 + , which is required for the activation of NO generation and release from the vascular endothelial cells. Nifedipine has no effect on either the endothelium-dependent relaxation or the cytosolic Ca2 + level in the cultured endothelial cells.CONCLUSION: Our findings are consistent with the known action of PNS on receptor-operated Ca2 + channels and support our contention that PNS inhibits endotheliumdependent relaxation by preventing the increase of Ca2 + level in endothelial cells via the receptor-operated Ca2 + channels in the presence of ACh or the non-selective cation channels opened by CPA.

  2. Hypercholesterolemic diet induces vascular smooth muscle cell apoptosis in sympathectomized rats via intrinsic pathway.

    Science.gov (United States)

    Hachani, Rafik; Dab, Houcine; Feriani, Anouar; Saber, Sami; Sakly, Mohsen; Vicaut, Eric; Callebert, Jacques; Sercombe, Richard; Kacem, Kamel

    2014-07-01

    In this study, we intend to investigate the role of hypercholesterolemic diet, a high risk factor for atherosclerosis, on vascular cell apoptosis in rats that have been previously sympathectomized. Thus, newborn male Wistar rats received injections of guanethidine for sympathectomy. Sham received injections of vehicle. The two groups were fed 1% cholesterol diet for 3months. Sympathectomy alone group was also exploited. Apoptosis in abdominal aortic tissue was identified by TUNEL method and conventional agarose gel electrophoresis to detect specific DNA fragmentation. Caspases 3 and 9, Bcl-2, Bax and cytochrome c were examined by immunoblotting. Oil Red O staining was used to reveal lipid in the arterial wall. Vascular smooth muscle cells (VSMCs) and macrophages were identified by immunostaining for α-smooth muscle actin and rat macrophage marker (ED1), respectively. The efficacy of sympathectomy was evaluated by analysis of perivascular sympathetic fibers. Our study showed that hypercholesterolemic diet, when performed in rats with neonatal sympathectomy, 1) increased aortic TUNEL-positive cells compared to sham and sympathectomy alone groups, 2) illustrated a typical apoptotic DNA ladder on agarose gel electrophoresis, 3) induced Bax translocation from cytosol to mitochondria, 4) enhanced cytochrome c release from mitochondria to cytosol, 5) increased expression of active caspases 3 and 9, and 6) decreased Bcl-2 expression. VSMCs are identified as the major cell type exhibiting apoptosis in this model. Taken together, it can be concluded that hypercholesterolemic diet, when performed in rats with neonatal sympathectomy, induces vascular cell apoptosis in an intrinsic pathway. PMID:24708922

  3. Influence of injected charge carriers on photocurrents in polymer solar cells

    OpenAIRE

    Wehenkel, Dominique J.; Koster, L. Jan Anton; Wienk, Martijn M.; Janssen, Rene A. J.

    2012-01-01

    We determine and analyze the photocurrent Jph in polymer solar cells under conditions where, no, one, or two different charge carriers can be injected by choosing appropriate electrodes and compare the experimental results to simulations based on a drift-diffusion device model that accounts for photogeneration and Langevin recombination of electrons and holes. We demonstrate that accounting for the series resistance of the device is essential to determine Jph. Without such correction, the res...

  4. Collagen microsphere serving as a cell carrier supports oligodendrocyte progenitor cell growth and differentiation for neurite myelination in vitro

    OpenAIRE

    Yao, Li; Phan, Francis; Li, Yongchao

    2013-01-01

    Introduction Microspheres fabricated from natural materials serve as a promising biodegradable and biocompatible carrier in a small volume for efficient cell delivery to the lesion of the injured neural tissue to generate biological functions. As the major component of extracellular matrix and due to its natural abundance within the body, collagen may be fabricated into microspheres and improve the ability of pre-seeded cells on the microspheres to encounter the hostile micro-environment in t...

  5. 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.

  6. Slow and sustained nitric oxide releasing compounds inhibit multipotent vascular stem cell proliferation and differentiation without causing cell death

    International Nuclear Information System (INIS)

    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

  7. Characterization of carrier concentration in CIGS solar cells by scanning capacitance microscopy

    International Nuclear Information System (INIS)

    Thin films of copper indium gallium selenide (CIGS) designed for highly efficient solar cell material were investigated to characterize the two-dimensional carrier distribution using scanning capacitance microscopy (SCM). We optimized a preparation method of the cross-section samples and concluded that bevel polishing by 25° to 30° was effective for crumbly polycrystalline materials such as CIGS, so as to provide not the surface property of cracked crystalline grains but the cross-section property of individual cut grains. Because of improvement in this preparation procedure, changes in carrier distribution have been observed directly in the active CIGS layer before and after turning on a 100 W halogen lamp irradiation. A calibration curve between carrier concentration N and SCM's dC/dV signals was applied for qualitatively calculating relative values of N in CIGS. Increased carrier concentration peaks on the grains were estimated to become about three times as high as those with the light on. (paper)

  8. Influence of stain etching on low minority carrier lifetime areas of multicrystalline silicon for solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Montesdeoca-Santana, A. [Departamento de Fisica Basica, Universidad de La Laguna, Avda. Astrofisico Francisco Sanchez, 38206 La Laguna (Spain); Fraunhofer Institute for Solar Energy Systems, Laboratory and Servicecenter Gelsenkirchen, Auf der Reihe 2, 45884 Gelsenkirchen (Germany); Gonzalez-Diaz, B. [Departamento de Fisica Basica, Universidad de La Laguna, Avda. Astrofisico Francisco Sanchez, 38206 La Laguna (Spain); Departamento de Energia Fotovoltaica, Instituto Tecnologico y de Energias Renovables. Poligono Industrial de Granadilla s/n, 38600 San Isidro-Granadilla de Abona (Spain); Jimenez-Rodriguez, E. [Departamento de Fisica Basica, Universidad de La Laguna, Avda. Astrofisico Francisco Sanchez, 38206 La Laguna (Spain); Ziegler, J. [Fraunhofer Institute for Solar Energy Systems, Laboratory- and Servicecenter Gelsenkirchen. Auf der Reihe 2, 45884 Gelsenkirchen (Germany); Velazquez, J.J. [Departamento de Fisica Fundamental y Experimental, Electronica y Sistemas, Universidad de La Laguna. Avda. Astrofisico Francisco Sanchez, 38206 La Laguna (Spain); Hohage, S.; Borchert, D. [Fraunhofer Institute for Solar Energy Systems, Laboratory and Servicecenter Gelsenkirchen. Auf der Reihe 2, 45884 Gelsenkirchen (Germany); Guerrero-Lemus, R., E-mail: rglemus@ull.es [Departamento de Fisica Basica, Universidad de La Laguna, Avda. Astrofisico Francisco Sanchez, 38206 La Laguna (Spain)

    2011-11-15

    Highlights: > An enhanced minority carrier lifetime at extended defects in multicrystalline silicon is observed with the use of HF/HNO{sub 3} stain etching to texture the surface. > FTIR analysis shows no influence of oxide passivation in this effect. > SEM images show a preferential etching at extended defects suggesting smoothing at defects as one of the causes for the reduced recombination activity. > LBIC images show a reduction in IQE at extended defects in HF/HNO{sub 3} textured multicrystalline solar cells. - Abstract: In this work the use of HF/HNO{sub 3} solutions for texturing silicon-based solar cell substrates by stain etching and the influence of texturing on minority carrier lifetimes are studied. Stain etching is currently used to decrease the reflectance and, subsequently improve the photogenerated current of the cells, but also produces nanostructures on the silicon surface. In the textured samples it has been observed that an improvement on the minority carrier lifetime with respect to the samples treated with a conventional saw damage etching process is produced on grain boundaries and defects, and the origin of this effect has been discussed.

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

    International Nuclear Information System (INIS)

    Objective: To investigate the effect of arsenic trioxide (As2O3) nanoparticles on rabbit vascular smooth muscle cells in vitro in comparison with normal form As2O3. Methods: The rabbit vascular smooth muscle cells were cultured in vitro. Nano and normal forms of As2O3 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 As2O3 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, P2O3, normal drug form of As2O3 and control group of cells without As2O3 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)

  10. Endothelial Nitric Oxide Synthase (−786T>C) and Endothelin-1 (5665G>T) Gene Polymorphisms as Vascular Dysfunction Risk Factors in Sickle Cell Anemia

    Science.gov (United States)

    Vilas-Boas, Wendell; Figueiredo, Camylla V. B.; Pitanga, Thassila N.; Carvalho, Magda O. S.; Santiago, Rayra P.; Santana, Sânzio S.; Guarda, Caroline C.; Zanette, Angela M. D.; Cerqueira, Bruno A. V.; Gonçalves, Marilda S.

    2016-01-01

    Sickle cell anemia (SCA) patients have vascular complications, and polymorphisms in endothelin-1 (ET-1) and endothelial nitric oxide synthase (eNOS) genes were associated with ET-1 and nitric oxide disturbance. We investigate the association of ET-1 5665G>T and eNOS −786T>C polymorphisms with soluble adhesion molecules (sVCAM-1 and sICAM-1), biochemical markers, and medical history. We studied 101 SCA patients; carriers of eNOS minor allele (C) had the highest levels of sVCAM-1, and carriers of ET-1 minor allele had more occurrence of acute chest syndrome (ACS). The multivariate analysis suggested the influence of the ET-1 gene on ACS outcome and an association of the eNOS gene with upper respiratory tract infection. We suggest that eNOS and ET-1 gene polymorphisms can influence SCA pathophysiology and that eNOS variant in SCA patients might be important to nitric oxide activity and vascular alteration. We found an association of the ET-1 minor allele in ACS, showing the importance of genetic screening in SCA. PMID:27486304

  11. 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 ...

  12. Hyperphosphatemia, Phosphoprotein Phosphatases, and Microparticle Release in Vascular Endothelial Cells.

    Science.gov (United States)

    Abbasian, Nima; Burton, James O; Herbert, Karl E; Tregunna, Barbara-Emily; Brown, Jeremy R; Ghaderi-Najafabadi, Maryam; Brunskill, Nigel J; Goodall, Alison H; Bevington, Alan

    2015-09-01

    Hyperphosphatemia in patients with advanced CKD is thought to be an important contributor to cardiovascular risk, in part because of endothelial cell (EC) dysfunction induced by inorganic phosphate (Pi). Such patients also have an elevated circulating concentration of procoagulant endothelial microparticles (MPs), leading to a prothrombotic state, which may contribute to acute occlusive events. We hypothesized that hyperphosphatemia leads to MP formation from ECs through an elevation of intracellular Pi concentration, which directly inhibits phosphoprotein phosphatases, triggering a global increase in phosphorylation and cytoskeletal changes. In cultured human ECs (EAhy926), incubation with elevated extracellular Pi (2.5 mM) led to a rise in intracellular Pi concentration within 90 minutes. This was mediated by PiT1/slc20a1 Pi transporters and led to global accumulation of tyrosine- and serine/threonine-phosphorylated proteins, a marked increase in cellular Tropomyosin-3, plasma membrane blebbing, and release of 0.1- to 1-μm-diameter MPs. The effect of Pi was independent of oxidative stress or apoptosis. Similarly, global inhibition of phosphoprotein phosphatases with orthovanadate or fluoride yielded a global protein phosphorylation response and rapid release of MPs. The Pi-induced MPs expressed VE-cadherin and superficial phosphatidylserine, and in a thrombin generation assay, they displayed significantly more procoagulant activity than particles derived from cells incubated in medium with a physiologic level of Pi (1 mM). These data show a mechanism of Pi-induced cellular stress and signaling, which may be widely applicable in mammalian cells, and in ECs, it provides a novel pathologic link between hyperphosphatemia, generation of MPs, and thrombotic risk. PMID:25745026

  13. Comparative study of antithrombin III. Protease complex metabolism by fibroblasts and vascular endothelial cells

    International Nuclear Information System (INIS)

    125I-labeled human antithrombin III (125I-AT III).protease complexes are specifically bound to both cultured human skin fibroblast (HSF) cells and adult bovine aortic endothelial (ABAE) cells; however, there is a significant difference in the rate and degree of metabolism of the complexes by these two cell types. HSF cells appear to internalize the complexes at a rate of about 2.5 pmole/1 X 10(6) cells/h and subsequently degrade them at a rate of 0.6 pmole/1 X 10(6) cells/h. ABAE cells internalize and degrade the complexes at rates approximately 100 and 30 times lower, respectively. Neither cell type interacts with free 125I-AT III but only with its combined form with either thrombin or trypsin. These data indicate the major role of HSF cells in the removal of AT III.protease complexes from extravascular spaces in the body, in contrast to the inert vascular surface with regard to AT III.protease complexes provided by the vascular endothelium

  14. Vascular endothelial growth factor A and vascular endothelial growth factor receptor 2 expression in non-small cell lung cancer patients: relation to prognosis

    DEFF Research Database (Denmark)

    Bonnesen, Barbara; Pappot, Helle; Holmstav, Julie;

    2009-01-01

    elements in neoplastic cells and their microenvironment have recently been and are continuously developed including drugs inhibiting the angiogenic system. Angiogenic factor vascular endothelial growth factor (VEGF) and its receptor vascular endothelial growth factor receptor 2 (VEGFR2) seem to play key...... stained on whole tumour slides. Kaplan-Meier survival curves were generated to evaluate the significance of immunohistochemical VEGF-A and VEGFR2 expression for the prognosis. RESULTS: VEGF-A and VEGFR2 expression was observed in the majority of NSCLC patients. VEGF-A expression showed a correlation to...

  15. Microscopic observation of carrier-transport dynamics in quantum-structure solar cells using a time-of-flight technique

    International Nuclear Information System (INIS)

    In this study, we propose a carrier time-of-flight technique to evaluate the carrier transport time across a quantum structure in an active region of solar cells. By observing the time-resolved photoluminescence signal with a quantum-well probe inserted under the quantum structure at forward bias, the carrier transport time can be efficiently determined at room temperature. The averaged drift velocity shows linear dependence on the internal field, allowing us to estimate the quantum structure as a quasi-bulk material with low effective mobility containing the information of carrier dynamics. We show that this direct and real-time observation is more sensitive to carrier transport than other conventional techniques, providing better insights into microscopic carrier transport dynamics to overcome a device design difficulty

  16. Microscopic observation of carrier-transport dynamics in quantum-structure solar cells using a time-of-flight technique

    Energy Technology Data Exchange (ETDEWEB)

    Toprasertpong, Kasidit; Fujii, Hiromasa; Sugiyama, Masakazu; Nakano, Yoshiaki [School of Engineering, The University of Tokyo, Bunkyo-ku, Tokyo 113-0032 (Japan); Kasamatsu, Naofumi; Kada, Tomoyuki; Asahi, Shigeo; Kita, Takashi [Graduate School of Engineering, Kobe University, Nada-ku, Kobe 657-8501 (Japan); Wang, Yunpeng; Watanabe, Kentaroh [Research Center for Advanced Science and Technology, The University of Tokyo, Meguro-ku, Tokyo 153-8904 (Japan)

    2015-07-27

    In this study, we propose a carrier time-of-flight technique to evaluate the carrier transport time across a quantum structure in an active region of solar cells. By observing the time-resolved photoluminescence signal with a quantum-well probe inserted under the quantum structure at forward bias, the carrier transport time can be efficiently determined at room temperature. The averaged drift velocity shows linear dependence on the internal field, allowing us to estimate the quantum structure as a quasi-bulk material with low effective mobility containing the information of carrier dynamics. We show that this direct and real-time observation is more sensitive to carrier transport than other conventional techniques, providing better insights into microscopic carrier transport dynamics to overcome a device design difficulty.

  17. Terapia celular no acidente vascular cerebral Cell therapy in strokes

    Directory of Open Access Journals (Sweden)

    Rosalia Mendez-Otero

    2009-05-01

    Full Text Available O AVC é o recordista em número de óbitos e a maior causa de incapacidade no Brasil. Apesar das inúmeras pesquisas realizadas ao longo dos últimos anos não há terapias farmacológicas adequadas para este quadro e, neste cenário, as terapias celulares vêm sendo consideradas como alternativas terapêuticas para diminuir as perdas funcionais decorrentes do AVC. Nesta revisão comentaremos os resultados de diversos estudos pré-clinicos e de alguns clínicos que utilizaram diferentes tipos de células-tronco em AVC.Stroke is the leading cause of death and incapacity in Brazil. Over the last few years, numerous preclinical and clinical studies have been carried out, however to date, none of the drugs tested in these studies were effective in patients. The emerging field of stem cell research has raised hope of therapy to ameliorate the functional loss after strokes. In this review we will discuss the results of several preclinical studies and clinical trials using different types of stem cells in the treatment of strokes.

  18. Zinc oxide particles induce inflammatory responses in vascular endothelial cells via NF-κB signaling

    International Nuclear Information System (INIS)

    This study investigated inflammatory effects of zinc oxide (ZnO) particles on vascular endothelial cells. The effects of 50 and 100-nm ZnO particles on human umbilical vein endothelial cells (HUVECs) were characterized by assaying cytotoxicity, cell proliferation, and glutathione levels. A marked drop in survival rate was observed when ZnO concentration was increased to 45 μg/ml. ZnO concentrations of ≤3 μg/ml resulted in increased cell proliferation, while those of ≤45 μg/ml caused dose-dependent increases in oxidized glutathione levels. Treatments with ZnO concentrations ≤45 μg/ml were performed to determine the expression of intercellular adhesion molecule-1 (ICAM-1) protein, an indicator of vascular endothelium inflammation, revealing that ZnO particles induced a dose-dependent increase in ICAM-1 expression and marked increases in NF-κB reporter activity. Overexpression of IκBα completely inhibited ZnO-induced ICAM-1 expression, suggesting NF-κB plays a pivotal role in regulation of ZnO-induced inflammation in HUVECs. Additionally, TNF-α, a typical inflammatory cytokine, induced ICAM-1 expression in an NF-κB-dependent manner, and ZnO synergistically enhanced TNF-α-induced ICAM-1 expression. Both 50 and 100-nm ZnO particles agglomerated to similar size distributions. This study reveals an important role for ZnO in modulating inflammatory responses of vascular endothelial cells via NF-κB signaling, which could have important implications for treatments of vascular disease.

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

    Directory of Open Access Journals (Sweden)

    Patrick Babczyk

    2014-01-01

    Full Text Available 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.

  20. Changes in adipose tissue stromal-vascular cells in primary culture due to porcine sera

    International Nuclear Information System (INIS)

    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 cm2 flasks, collagen-coated coverslips or petri dishes. Cell proliferation was measured by [3H]-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

  1. Bone morphogenetic proteins regulate osteoprotegerin and its ligands in human vascular smooth muscle cells

    DEFF Research Database (Denmark)

    Knudsen, Kirsten Quyen Nguyen; Olesen, Ping; Ledet, Thomas;

    2007-01-01

    ) and TNF-related apoptosis-inducing ligand (TRAIL) in HVSMC. All three growth factors decreased OPG protein production significantly; these results were paralleled by reduced OPG mRNA expression. TRAIL mRNA levels were also decreased. RANKL mRNA expression declined when treated with TGF-beta1 but were......The bone-related protein osteoprotegerin (OPG) may be involved in the development of vascular calcifications, especially in diabetes, where it has been found in increased amounts in the arterial wall. Experimental studies suggest that members of the TGF-superfamily are involved in the...... transformation of human vascular smooth muscle cells (HVSMC) to osteoblast-like cells. In this study, we evaluated the effect of BMP-2, BMP-7 and transforming growth factor beta (TGF-beta1) on the secretion and mRNA expression of OPG and its ligands receptor activator of nuclear factor-kappabeta ligand (RANKL...

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

    Science.gov (United States)

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

    2016-10-01

    There is an increasing demand for functional small-diameter vascular grafts (diameterpolycaprolactone, 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. PMID:27287133

  3. Fibulin-2 is present in murine vascular lesions and is important for smooth muscle cell migration

    DEFF Research Database (Denmark)

    Ström, A.; Olin, A. I.; Aspberg, A.;

    2006-01-01

    and is upregulated during SMC phenotypic modulation in cell culture. Moreover, treatments with peptides that block the interaction between versican and fibulin-2 inhibit SMC migration in vitro. Conclusions: Fibulin-2 can be produced by SMC as a response to injury and may participate in the ECM organisation......Objective: The vascular extracellular matrix (ECM) can affect smooth muscle cell (SMC) adhesion, migration and proliferation-events that are important during the atherosclerotic process. Fibulin-2 is a member of the ECM protein family of fibulins and has been found to cross-link versican....../hyaluronan complexes, an ECM network that has been suggested to be important during tissue repair. In this study we have analysed the presence of fibulin-2 in two different models of murine vascular lesions. We have also examined how the fibulin-2/versican network influences SMC migration. Methods: Presence of fibulin...

  4. Low-dose effects of Bisphenol A on human primary vascular endothelial cells and colon cancer cells

    OpenAIRE

    Varandas, Edna Soraia Gregório Ribeiro Varandas

    2014-01-01

    Bisphenol A (BPA) is an extensively utilized endocrine disruptor for which human exposure is considered generalized through ingestion. Information regarding BPA effects on vascular and digestive tract tissues is scarce. Therefore, in this work primary Human Umbilical Vein Endothelial Cells (HUVEC) and human colon adenocarcinona cell line HT29 were used to evaluate BPA effects at two distinct low-dose concentrations relevant in terms of human health risk assessment. BPA di...

  5. 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.

  6. Onychin inhibits proliferation of vascular smooth muscle cells by regulating cell cycle

    Institute of Scientific and Technical Information of China (English)

    Ming YANG; Hong-lin HUANG; Bing-yang ZHU; Qin-hui TUO; Duan-fang LIAO

    2005-01-01

    Aim: To investigate the effects of onychin on the proliferation of cultured rat artery vascular smooth muscle cells (VSMCs) in the presence of 10% new-borncalf serum (NCS). Methods: Rat VSMCs were incubated with onychin 1-50 μmol/L or genistein 10 μmol/L in the presence of 10% NCS for 24 h. The proliferation of VSMCs was measured by cell counting and MTS/PMS colorimetric assays. Cell cycle progression was evaluated by flow cytometry. Retinoblastoma (Rb) phosphorylation, and expression of cyclin D1 and cyclin E were measured by Western blot assays. The tyrosine phosphorylation of ERK1/2 was examined by immunoprecipitation techniques using anti-phospho-tyrosine antibodies. Results: The proliferation of VSMCs was accelerated significantly in the presence of 10% NCS. Onychin reduced the metabolic rate of MTS and the cell number of VSMCs in the presence of 10% NCS in a dose-dependent manner. Flow cytometry analy sis revealed that the G1-phase fraction ratio in the onychin group was higher than that in the 10% NCS group (85.2% vs 70.0%, P<0.01), while the S-phase fraction ratio in the onychin group was lower than that in 10% NCS group (4.3% vs 16.4%, P<0.01). Western blot analysis showed that onychin inhibited Rb phos phorylation and reduced the expression of cyclin D1 and cyclin E. The effects of onychin on proliferation, the cell cycle and the expression of cyclins in VSMCs were similar to those of genistein, an inhibitor of tyrosine kinase. Furthermore immunoprecipitation studies showed that both onychin and genistein markedly inhibited the tyrosine phosphorylation of ERK1/2 induced by 10% NCS.Conclusion: Onychin inhibits the proliferation of VSMCs through G1 phase cell cycle arrest by decreasing the tyrosine phosphorylation of ERK1/2, and the expression of cyclin D1 and cyclin E, and sequentially inhibiting Rb phosphorylation.

  7. Dextran based nanosized carrier for the controlled and targeted delivery of curcumin to liver cancer cells.

    Science.gov (United States)

    Anirudhan, Thayyath Sreenivasan; Binusreejayan

    2016-07-01

    Curcumin (Cur), a poly phenolic yellow colored compound present in Indian spice turmeric, has a wide variety of biological properties. Bioavailability of Cur is limited by its low water solubility, rapid metabolism and low stability. In the present study, we mainly focus on synthesis and characterization of dextran based nano-sized drug carrier (GHDx) for the delivery of Cur. A liver targeting moiety is incorporated in GHDx so as to improve the therapeutic efficiency and decrease adverse effects of conventional cancer therapy. The effect of different parameters on grafting variables was studied. GHDx was characterised by FTIR, (1)H NMR XRD, TG/DTG, TEM, SEM, AFM, DLS and zeta potential analyses. Adsorption experiments were carried out for drug loading. Swelling of GHDx was studied as a function of pH and temperature. Three step release of Cur from GHDx was confirmed by analyzing in vitro release data in simulated intracellular pH using different kinetic models. In vitro cytotoxicity analysis on L929 and Hep G2 cells shows that GHDx is safe carrier while Cur loaded GHDx exhibits high toxicity with slow drug release towards hepatic cells. The results show that the GHDx can be customized as a stimuli sensitive potential carrier for the delivery of drugs. PMID:27012895

  8. Peptide nucleic acid (PNA) cell penetrating peptide (CPP) conjugates as carriers for cellular delivery of antisense oligomers

    DEFF Research Database (Denmark)

    Shiraishi, Takehiko; Nielsen, Peter E

    2012-01-01

    We have explored the merits of a novel delivery strategy for the antisense oligomers based on cell penetrating peptide (CPP) conjugated to a carrier PNA with sequence complementary to part of the antisense oligomer. The effect of these carrier CPP-PNAs was evaluated by using antisense PNA targeting...... splicing correction of the mutated luciferase gene in the HeLa pLuc705 cell line, reporting cellular (nuclear) uptake of the antisense PNA via luciferase activity measurement. Carrier CPP-PNA constructs were studied in terms of construct modification (with octaarginine and/or decanoic acid) and carrier PNA...... length (to adjust binding affinity). In general, the carrier CPP-PNA constructs including the ones with decanoyl modification provided significant increase of the activity of unmodified antisense PNA as well as of antisense octaarginine-PNA conjugates. Antisense activity, and by inference cellular...

  9. Nitroglycerin induces DNA damage and vascular cell death in the setting of nitrate tolerance.

    Science.gov (United States)

    Mikhed, Yuliya; Fahrer, Jörg; Oelze, Matthias; Kröller-Schön, Swenja; Steven, Sebastian; Welschof, Philipp; Zinßius, Elena; Stamm, Paul; Kashani, Fatemeh; Roohani, Siyer; Kress, Joana Melanie; Ullmann, Elisabeth; Tran, Lan P; Schulz, Eberhard; Epe, Bernd; Kaina, Bernd; Münzel, Thomas; Daiber, Andreas

    2016-07-01

    Nitroglycerin (GTN) and other organic nitrates are widely used vasodilators. Their side effects are development of nitrate tolerance and endothelial dysfunction. Given the potential of GTN to induce nitro-oxidative stress, we investigated the interaction between nitro-oxidative DNA damage and vascular dysfunction in experimental nitrate tolerance. Cultured endothelial hybridoma cells (EA.hy 926) and Wistar rats were treated with GTN (ex vivo: 10-1000 µM; in vivo: 10, 20 and 50 mg/kg/day for 3 days, s.c.). The level of DNA strand breaks, 8-oxoguanine and O (6)-methylguanine DNA adducts was determined by Comet assay, dot blot and immunohistochemistry. Vascular function was determined by isometric tension recording. DNA adducts and strand breaks were induced by GTN in cells in vitro in a concentration-dependent manner. GTN in vivo administration leads to endothelial dysfunction, nitrate tolerance, aortic and cardiac oxidative stress, formation of DNA adducts, stabilization of p53 and apoptotic death of vascular cells in a dose-dependent fashion. Mice lacking O (6)-methylguanine-DNA methyltransferase displayed more vascular O (6)-methylguanine adducts and oxidative stress under GTN therapy than wild-type mice. Although we were not able to prove a causal role of DNA damage in the etiology of nitrate tolerance, the finding of GTN-induced DNA damage such as the mutagenic and toxic adduct O (6)-methylguanine, and cell death supports the notion that GTN based therapy may provoke adverse side effects, including endothelial function. Further studies are warranted to clarify whether GTN pro-apoptotic effects are related to an impaired recovery of patients upon myocardial infarction. PMID:27357950

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

    OpenAIRE

    Son, Dong Ju; Kim, Soo Yeon; Han, Seong Su; Kim, Chan Woo; Kumar, Sandeep; Park, Byeoung Soo; Lee, Sung Eun; Yun, Yeo Pyo; Jo, Hanjoong; Park, Young Hyun

    2012-01-01

    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 significant...

  11. miR-599 Inhibits Vascular Smooth Muscle Cells Proliferation and Migration by Targeting TGFB2

    OpenAIRE

    Baodong Xie; Chunfeng Zhang; Kai Kang; Shulin Jiang

    2015-01-01

    Aberrant proliferation and migration of vascular smooth muscle cells (VSMCs) play a crucial role in the pathogenesis of cardiovascular diseases including coronary heart disease, restenosis and atherosclerosis. MicroRNAs are a class of small, non-coding and endogenous RNAs that play critical roles in VSMCs function. In this study, we showed that PDGF-bb, as a stimulant, promoted VSMCs proliferation and suppressed the expression of miR-599. Moreover, overexpression of miR-599 inhibited VSMCs pr...

  12. The Fat1 cadherin integrates vascular smooth muscle cell growth and migration signals

    OpenAIRE

    Hou, Rong; Liu, Liming; Anees, Syed; Hiroyasu, Shungo; Sibinga, Nicholas E. S.

    2006-01-01

    The significance of cadherin superfamily proteins in vascular smooth muscle cell (VSMC) biology is undefined. Here we describe recent studies of the Fat1 protocadherin. Fat1 expression in VSMCs increases significantly after arterial injury or growth factor stimulation. Fat1 knockdown decreases VSMC migration in vitro, but surprisingly, enhances cyclin D1 expression and proliferation. Despite limited similarity to classical cadherins, the Fat1 intracellular domain (Fat1IC) interacts with β-cat...

  13. Akt1/PKB upregulation leads to vascular smooth muscle cell hypertrophy and polyploidization

    OpenAIRE

    Hixon, Mary L.; Muro-Cacho, Carlos; Wagner, Mark W.; Obejero-Paz, Carlos; Millie, Elise; Fujio, Yasushi; Kureishi, Yasuko; Hassold, Terry; Walsh, Kenneth; Gualberto, Antonio

    2000-01-01

    Vascular smooth muscle cells (VSMCs) at capacitance arteries of hypertensive individuals and animals undergo marked age- and blood pressure–dependent polyploidization and hypertrophy. We show here that VSMCs at capacitance arteries of rat models of hypertension display high levels of Akt1/PKB protein and activity. Gene transfer of Akt1 to VSMCs isolated from a normotensive rat strain was sufficient to abrogate the activity of the mitotic spindle cell–cycle checkpoint, promoting polyploidizati...

  14. Systemic immunotherapy delays photoreceptor cell loss and prevents vascular pathology in Royal College of Surgeons rats

    OpenAIRE

    Adamus, Grazyna; Wang, Shaomei; Kyger, Madison; Worley, Aneta; Lu, Bin; Burrows, Gregory G.

    2012-01-01

    Purpose Degenerative retinopathies, including retinitis pigmentosa, age-related retinal degeneration, autoimmune retinopathy, and related diseases affect millions of people around the world. Currently, there is no effective treatment for most of those diseases. We investigated systemic recombinant T-cell receptor ligand (RTL) immunotherapy for preventing retinal degeneration and vascular damage in the Royal College of Surgeons (RCS) rat model of retinal degeneration. Methods RCS rats were tre...

  15. Electroporation of human microvascular endothelial cells: evidence for an anti-vascular mechanism of electrochemotherapy

    OpenAIRE

    Cemazar, M; Parkins, C. S.; Holder, A L; Chaplin, D. J.; Tozer, G. M.; Sersa, G

    2001-01-01

    Recent studies have indicated that the antitumour effectiveness of electrochemotherapy, a combination of chemotherapeutic drugs with application of high voltage electric pulses applied to the tumour nodule (electroporation), result in a significant reduction in tumour blood flow and may therefore be mediated by an anti-vascular mechanism. The aim of this study was to evaluate the cytotoxicity of electroporation with bleomycin or cisplatin on cultured human microvascular endothelial cells (HME...

  16. Vascular smooth muscle cell-derived adiponectin: a paracrine regulator of contractile phenotype

    OpenAIRE

    Ding, Min; Carrao, Ana Catarina; Wagner, Robert J.; Xie, Yi; Jin, Yu; Rzucidlo, Eva M.; Yu, Jun; Li, Wei; Tellides, George; Hwa, John; Aprahamian, Tamar R.; Martin, Kathleen A.

    2011-01-01

    Adiponectin is a cardioprotective adipokine derived predominantly from visceral fat. We recently demonstrated that exogenous adiponectin induces vascular smooth muscle cell (VSMC) differentiation via repression of mTORC1 and FoxO4. Here we report for the first time that VSMC express and secrete adiponectin, which acts in an autocrine and paracrine manner to regulate VSMC contractile phenotype. Adiponectin was found to be expressed in human coronary artery and mouse aortic VSMC. Importantly, s...

  17. pH-Sensitive and Thermosensitive Hydrogels as Stem-Cell Carriers for Cardiac Therapy.

    Science.gov (United States)

    Li, Zhenqing; Fan, Zhaobo; Xu, Yanyi; Lo, Wilson; Wang, Xi; Niu, Hong; Li, Xiaofei; Xie, Xiaoyun; Khan, Mahmood; Guan, Jianjun

    2016-05-01

    Stem-cell therapy has the potential to regenerate damaged heart tissue after a heart attack. Injectable hydrogels may be used as stem-cell carriers to improve cell retention in the heart tissue. However, current hydrogels are not ideal to serve as cell carriers because most of them block blood vessels after solidification. In addition, these hydrogels have a relatively slow gelation rate (typically >60 s), which does not allow them to quickly solidify upon injection, so as to efficiently hold cells in the heart tissue. As a result, the hydrogels and cells are squeezed out of the tissue, leading to low cell retention. To address these issues, we have developed hydrogels that can quickly solidify at the pH of an infarcted heart (6-7) at 37 °C but cannot solidify at the pH of blood (7.4) at 37 °C. These hydrogels are also clinically attractive because they can be injected through catheters commonly used for minimally invasive surgeries. The hydrogels were synthesized by free-radical polymerization of N-isopropylacrylamide, propylacrylic acid, hydroxyethyl methacrylate-co-oligo(trimethylene carbonate), and methacrylate poly(ethylene oxide) methoxy ester. Hydrogel solutions were injectable through 0.2-mm-diameter catheters at pH 8.0 at 37 °C, and they can quickly form solid gels under pH 6.5 at 37 °C. All of the hydrogels showed pH-dependent degradation and mechanical properties with less mass loss and greater complex shear modulus at pH 6.5 than at pH 7.4. When cardiosphere-derived cells (CDCs) were encapsulated in the hydrogels, the cells were able to survive during a 7-day culture period. The surviving cells were differentiated into cardiac cells, as evidenced by the expression of cardiac markers at both the gene and protein levels, such as cardiac troponin T, myosin heavy chain α, calcium channel CACNA1c, cardiac troponin I, and connexin 43. The gel integrity was found to largely affect CDC cardiac differentiation. These results suggest that the developed dual

  18. 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.

  19. Enhancing light absorption within the carrier transport length in quantum junction solar cells.

    Science.gov (United States)

    Fu, Yulan; Hara, Yukihiro; Miller, Christopher W; Lopez, Rene

    2015-09-10

    Colloidal quantum dot (CQD) solar cells have attracted tremendous attention because of their tunable absorption spectrum window and potentially low processing cost. Recently reported quantum junction solar cells represent a promising approach to building a rectifying photovoltaic device that employs CQD layers on each side of the p-n junction. However, the ultimate efficiency of CQD solar cells is still highly limited by their high trap state density in both p- and n-type CQDs. By modeling photonic structures to enhance the light absorption within the carrier transport length and by ensuring that the carrier generation and collection efficiencies were both augmented, our work shows that overall device current density could be improved. We utilized a two-dimensional numerical model to calculate the characteristics of patterned CQD solar cells based on a simple grating structure. Our calculation predicts a short circuit current density as high as 31  mA/cm2, a value nearly 1.5 times larger than that of the conventional flat design, showing the great potential value of patterned quantum junction solar cells. PMID:26368966

  20. Cell carrier function of hollow-fiber membrane in rotating wall vessel bioreactor

    Institute of Scientific and Technical Information of China (English)

    Kedong SONG; Tianqing LIU; Hu ZHAO; Xiangqin LI; Zhanfeng CUI; Xuehu MA

    2008-01-01

    Large-scale expansion of the osteoblasts of a Sprague-Dawley (SD) rat was studied in a rotating wall hollow-fiber membrane bioreactor (RWHMB) by using hollow-fiber membrane as the carrier. For the sake of contrast, cells were also expanded in a T-flask using a hollow-fiber membrane as carrier and in a rotating wall vessel bioreactor (RWVB) using a microcarrier. During the culture period, the cells were sampled every 12 h, and after 5 days, the cells were harvested and evaluated with scanning electron microscopy (SEM), hematoxylin-eosin (HE) staining and alkaline phosphatase (ALP) staining. Moreover, von-Kossa staining and Alizarin Red S stain-ing were carried out for mineralized nodules formation. The results show that in RWHMB, the cells present better morphology and vitality and secrete much more extracel-lular matrix. It is concluded that the RWHMB combines the advantages of the rotating wall vessel and hollow-fiber membrane bioreactors. The hydrodynamic stimulation within it accelerates the metabolism of the osteoblast and mass transfer, which is propitious to cell differenti-ation and proliferation.

  1. Anti-Proliferative Effect of an Aqueous Extract of Prunella vulgaris in Vascular Smooth Muscle Cells

    Directory of Open Access Journals (Sweden)

    Sun Mi Hwang

    2013-01-01

    Full Text Available The abnormal proliferation of vascular smooth muscle cells (VSMCs in arterial walls is an important pathogenic factor of vascular disorders such as diabetic atherosclerosis. We have reported the anti-inflammatory effect of an aqueous extract from Prunella vulgaris (APV in vascular endothelial cell. In the present study, APV exhibited inhibitory effects on high glucose-stimulated VSMC proliferation, migration, and invasion activities, inducing G1 cell cycle arrest with downregulation of cyclins and CDKs and upregulation of the CKIs, p21waf1/cip1 and p27kip1. Furthermore, APV dose dependently suppressed the high glucose-induced matrix metalloproteinase activity. High glucose-induced phosphorylation of ERK, p38 MAPK, was decreased by the pretreatment of APV. NF-κB activation by high glucose was attenuated by APV, as an antioxidant. APV attenuated the high glucose-induced decrease of nuclear factor E2-related factor-2 (Nrf2 translocation and heme oxygenase-1 (HO-1 expression. Intracellular cGMP level was also increased by APV treatment. These results demonstrate that APV may inhibit VSMC proliferation via downregulating ROS/NF-κB /ERK/p38 MAPK pathways. In addition, APV has a beneficial effect by the interaction of Nrf2-mediated NO/cGMP with HO-1, suggesting that Prunella vulgaris may be useful in preventing diabetic atherosclerosis.

  2. 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.

  3. In Vivo Vascularization of Endothelial Cells Derived from Bone Marrow Mesenchymal Stem Cells in SCID Mouse Model

    Directory of Open Access Journals (Sweden)

    Allameh Abdolamir

    2016-07-01

    Full Text Available Objective In vivo and in vitro stem cell differentiation into endothelial cells is a promising area of research for tissue engineering and cell therapy. Materials and Methods We induced human mesenchymal stem cells (MSCs to differentiate to endothelial cells that had the ability to form capillaries on an extracellular matrix (ECM gel. Thereafter, the differentiated endothelial cells at early stage were characterized by expression of specific markers such as von Willebrand factor (vWF, vascular endothelial growth factor (VEGF receptor 2, and CD31. In this experimental model, the endothelial cells were transplanted into the groins of severe combined immunodeficiency (SCID mice. After 30 days, we obtained tissue biopsies from the transplantation sites. Biopsies were processed for histopathological and double immunohistochemistry (DIHC staining. Results Endothelial cells at the early stage of differentiation expressed endothelial markers. Hematoxylin and eosin (H&E staining, in addition to DIHC demonstrated homing of the endothelial cells that underwent vascularization in the injected site. Conclusion The data clearly showed that endothelial cells at the early stage of differentiation underwent neovascularization in vivo in SCID mice. Endothelial cells at their early stage of differentiation have been proven to be efficient for treatment of diseases with impaired vasculogenesis.

  4. Physiological tests for yeast brewery cells immobilized on modified chamotte carrier.

    Science.gov (United States)

    Berlowska, Joanna; Kregiel, Dorota; Ambroziak, Wojciech

    2013-11-01

    In this study yeast cell physiological activity was assessed on the basis of the in situ activity of two important enzymes, succinate dehydrogenase and pyruvate decarboxylase. FUN1 dye bioconversion and cellular ATP content were also taken as important indicators of yeast cell activity. The study was conducted on six brewing yeast strains, which were either free cells or immobilized on a chamotte carrier. The experimental data obtained indicate clearly that, in most cases, the immobilized cells showed lower enzyme activity than free cells from analogous cultures. Pyruvate decarboxylase activity in immobilized cells was higher than in planktonic cell populations only in the case of the Saccharomyces pastorianus 680 strain. However, in a comparative assessment of the fermentation process, conducted with the use of free and immobilized cells, much more favorable dynamics and carbon dioxide productivity were observed in immobilized cells, especially in the case of brewing lager yeast strains. This may explain the higher total cell density per volume unit of the fermented medium and the improved resistance of immobilized cells to environmental changes. PMID:23887884

  5. 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)

  6. Enhanced adherence of mouse fibroblast and vascular cells to plasma modified polyethylene

    International Nuclear Information System (INIS)

    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)

  7. 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.

  8. Non-expanded adipose stromal vascular fraction cell therapy for multiple sclerosis

    Directory of Open Access Journals (Sweden)

    Rodriguez Jorge

    2009-04-01

    Full Text Available Abstract The stromal vascular fraction (SVF of adipose tissue is known to contain mesenchymal stem cells (MSC, T regulatory cells, endothelial precursor cells, preadipocytes, as well as anti-inflammatory M2 macrophages. Safety of autologous adipose tissue implantation is supported by extensive use of this procedure in cosmetic surgery, as well as by ongoing studies using in vitro expanded adipose derived MSC. Equine and canine studies demonstrating anti-inflammatory and regenerative effects of non-expanded SVF cells have yielded promising results. Although non-expanded SVF cells have been used successfully in accelerating healing of Crohn's fistulas, to our knowledge clinical use of these cells for systemic immune modulation has not been reported. In this communication we discuss the rationale for use of autologous SVF in treatment of multiple sclerosis and describe our experiences with three patients. Based on this rationale and initial experiences, we propose controlled trials of autologous SVF in various inflammatory conditions.

  9. Calcium phosphate nanoparticles as versatile carrier for small and large molecules across cell membranes

    International Nuclear Information System (INIS)

    The successful transport of molecules across the cell membrane is a key point in biology and medicine. In most cases, molecules alone cannot penetrate the cell membrane, therefore an efficient carrier is needed. Calcium phosphate nanoparticles (diameter: 100–250 nm, depending on the functionalization) were loaded with fluorescent oligonucleotides, peptide, proteins, antibodies, polymers or porphyrins and characterized by dynamic light scattering, nanoparticle tracking analysis and scanning electron microscopy. Any excess of molecules was removed by ultracentrifugation, and the dissolved molecules at the same concentration were used as control. The uptake of such fluorescence-labeled nanoparticles into HeLa cells was monitored by fluorescence microscopy and confocal laser scanning microscopy. Calcium phosphate nanoparticles were able to transport all molecules across the cell membrane, whereas the dissolved molecules alone were taken up only to a very small extent or even not at all.

  10. Ethanol production and the effect of porous polymer carriers on immobilized growing yeast cells by radiation-induced polymerization

    International Nuclear Information System (INIS)

    As a means of producing ethanol as fuel from waste cellulose, yeast cells were immobilized by radiation-induced polymerization. Precultured yeast cells were incubated aerobically at 300C for 24 h with porous polymer carriers prepared by radiation-induced polymerization at a low temperature. Yeast cells adsorbed on the surface of these porous carriers were immersed in monomer solution and were immobilized by radiation-induced polymerization of this monomer. The maximum ethanol productivity in an immobilized yeast cell system was found to be about 10 times greater than that in a free yeast cell system. (author)

  11. Physiology and pathophysiology of oxLDL uptake by vascular wall cells in atherosclerosis.

    Science.gov (United States)

    Di Pietro, Natalia; Formoso, Gloria; Pandolfi, Assunta

    2016-09-01

    Atherosclerosis is a progressive disease in which endothelial cell dysfunction, macrophage foam cell formation, and smooth muscle cell migration and proliferation, lead to the loss of vascular homeostasis. Oxidized low-density lipoprotein (oxLDL) may play a pre-eminent function in atherosclerotic lesion formation, even if their role is still debated. Several types of scavenger receptors (SRs) such as SR-AI/II, SRBI, CD36, lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1), toll-like receptors (TLRs) and others can promote the internalization of oxLDL. They are expressed on the surface of vascular wall cells (endothelial cells, macrophages and smooth muscle cells) and they mediate the cellular effects of oxLDL. The key influence of both oxLDL and SRs on the atherogenic process has been established in atherosclerosis-prone animals, in which antioxidant treatment and/or silencing of SRs has been shown to reduce atherogenesis. Despite some discrepancies, the indication from cohort studies that there is an association between oxLDL and cardiovascular (CV) events seems to point toward a role for oxLDL in atherosclerotic plaque progress and disruption. Finally, randomized clinical trials using antioxidants have demonstrated benefits only in high-risk patients, suggesting that additional proofs are still needed to better define the involvement of each type of modified LDL in the development of atherosclerosis. PMID:27256928

  12. 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.

  13. 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. PMID:27012600

  14. SIRT1 inhibits angiotensin Ⅱ-induced vascular smooth muscle cell hypertrophy

    Institute of Scientific and Technical Information of China (English)

    Li Li; Chihchuan Liang; Peng Gao; Huina Zhang; Houzao Chen; Wei Zheng; Xiang Lv; Tingting Xu; Yusheng Wei; Depei Liu

    2011-01-01

    Angiotensin Ⅱ (Ang Ⅱ) stimulates vascular smooth muscle cell (VSMC) hypertrophy as a critical event in the development of vascular diseases such as atherosclerosis.Sirtuin (SIRT) 1, a nicotinamide adenine dinucleotide dependent deacetylase, has been demonstrated to exert protective effects in atherosclerosis by promoting endo-thelium-dependent vascular relaxation and reducing macrophage foam cell formation, but its role in VSMC hypertrophy remains unknown. In this study, we tried to investigate the effect of SIRTI on Ang Ⅱ-induced VSMC hypertrophy. Results showed that adenoviral-mediated over-expression of SIRT1 significantly inhibited Ang Ⅱ-induced VSMC hypertrophy, while knockdown of SIRT1 by RNAi resulted in an increased [3H]-leucine incorpor-ation of VSMC. Accordingly, nicotinamide adenine dinu-cleotide phosphate oxidase 1 (Nox1) expression induced by Ang Ⅱ was inhibited by SIRT1 in VSMCs. SIRT1 acti-vator resveratrol decreased, whereas endogenous SIRT1 inhibitor nicotinamide increased Nox1 expression in A7r5 VSMCs. Furthermore, transcription factor GATA-6 was involved in the down-regulation of Nox1 expression by SIRT1. These results provide new insight into SIRTI's anti-atherogenic properties by suppressing Ang Ⅱ-induced VSMC hypertrophy.

  15. Resonant tunneling diodes as energy-selective contacts used in hot-carrier solar cells

    Science.gov (United States)

    Takeda, Yasuhiko; Ichiki, Akihisa; Kusano, Yuya; Sugimoto, Noriaki; Motohiro, Tomoyoshi

    2015-09-01

    Among the four features unique to hot-carrier solar cells (HC-SCs): (i) carrier thermalization time and (ii) carrier equilibration time in the absorber, (iii) energy-selection width and (iv) conductance of the energy-selective contacts (ESCs), requisites of (i)-(iii) for high conversion efficiency have been clarified. We have tackled the remaining issues related to (iv) in the present study. The detailed balance model of HC-SC operation has been improved to involve a finite value of the ESC conductance to find the required values, which in turn has been revealed to be feasible using resonant tunneling diodes (RTDs) consisting of semiconductor quantum dots (QDs) and quantum wells (QWs) by means of a formulation to calculate the conductance of the QD- and QW-RTDs derived using the rigorous solutions of the effective-mass Hamiltonians. Thus, all of the four requisites unique to HC-SCs to achieve high conversion efficiency have been elucidated, and the two requisites related to the ESCs can be fulfilled using the QD- and QW-RTDs.

  16. Resonant tunneling diodes as energy-selective contacts used in hot-carrier solar cells

    International Nuclear Information System (INIS)

    Among the four features unique to hot-carrier solar cells (HC-SCs): (i) carrier thermalization time and (ii) carrier equilibration time in the absorber, (iii) energy-selection width and (iv) conductance of the energy-selective contacts (ESCs), requisites of (i)-(iii) for high conversion efficiency have been clarified. We have tackled the remaining issues related to (iv) in the present study. The detailed balance model of HC-SC operation has been improved to involve a finite value of the ESC conductance to find the required values, which in turn has been revealed to be feasible using resonant tunneling diodes (RTDs) consisting of semiconductor quantum dots (QDs) and quantum wells (QWs) by means of a formulation to calculate the conductance of the QD- and QW-RTDs derived using the rigorous solutions of the effective-mass Hamiltonians. Thus, all of the four requisites unique to HC-SCs to achieve high conversion efficiency have been elucidated, and the two requisites related to the ESCs can be fulfilled using the QD- and QW-RTDs

  17. 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. PMID:27016579

  18. Indirect co‑culture of vascular smooth muscle cells with bone marrow mesenchymal stem cells inhibits vascular calcification and downregulates the Wnt signaling pathways.

    Science.gov (United States)

    Zhu, Meng'en; Fang, Xin; Zhou, Shaoqiong; Li, Wei; Guan, Siming

    2016-06-01

    Vascular calcification (VC) is widely considered to be a crucial clinical indicator of cardiovascular disease. Recently, certain properties of mesenchymal stem cells (MSCs) have been hypothesized to have potential in treating cardiovascular diseases. However, their effect on the initiation and progression of VC remains controversial. The present study aimed to investigate whether MSCs indirectly mediate VC and their impact on the Wnt signaling pathways. A Transwell system was selected to establish the indirect co‑culture environment, and hence, vascular smooth muscle cells (VSMCs) were indirectly co‑cultured in the presence or absence of MSCs at a ratio of 1:1. Osteogenic medium (OS) was added to imitate a calcifying environment. Fourteen days later, VSMCs in the lower layers of the Transwell plates were harvested. Alkaline phosphatase activity and calcium nodules were markedly increased in calcific VSMCs induced by OS. However, these parameters were significantly decreased in VSMCs by indirectly co‑culturing with MSCs in the same medium. Furthermore, the messenger RNA expression levels of osteopontin and osteoprotegerin were notably increased in VSMCs cultured in OS, but reduced by indirect interaction with MSCs. In addition, the activities of canonical and noncanonical Wnt ligands, wingless‑type MMTV integration site family, number 5A (Wnt5a), receptor tyrosine kinase‑like orphan receptor 2 (Ror2) and β‑catenin, which are important in the process of VC, were downregulated by indirect contact with MSCs in OS. Thus, indirect co‑culture with MSCs inhibits VC and downregulates the Wnt signaling pathways. PMID:27121342

  19. Dimethylfumarate attenuates restenosis after acute vascular injury by cell-specific and Nrf2-dependent mechanisms

    Directory of Open Access Journals (Sweden)

    Chang Joo Oh

    2014-01-01

    Full Text Available Excessive proliferation of vascular smooth muscle cells (VSMCs and incomplete re-endothelialization is a major clinical problem limiting the long-term efficacy of percutaneous coronary angioplasty. We tested if dimethylfumarate (DMF, an anti-psoriasis drug, could inhibit abnormal vascular remodeling via NF−E2-related factor 2 (Nrf2-NAD(PH quinone oxidoreductase 1 (NQO1 activity. DMF significantly attenuated neointimal hyperplasia induced by balloon injury in rat carotid arteries via suppression of the G1 to S phase transition resulting from induction of p21 protein in VSMCs. Initially, DMF increased p21 protein stability through an enhancement in Nrf2 activity without an increase in p21 mRNA. Later on, DMF stimulated p21 mRNA expression through a process dependent on p53 activity. However, heme oxygenase-1 (HO-1 or NQO1 activity, well-known target genes induced by Nrf2, were dispensable for the DMF induction of p21 protein and the effect on the VSMC proliferation. Likewise, DMF protected endothelial cells from TNF-α-induced apoptosis and the dysfunction characterized by decreased eNOS expression. With knock-down of Nrf2 or NQO1, DMF failed to prevent TNF-α-induced cell apoptosis and decreased eNOS expression. Also, CD31 expression, an endothelial specific marker, was restored in vivo by DMF. In conclusion, DMF prevented abnormal proliferation in VSMCs by G1 cell cycle arrest via p21 upregulation driven by Nrf2 and p53 activity, and had a beneficial effect on TNF-α-induced apoptosis and dysfunction in endothelial cells through Nrf2–NQO1 activity suggesting that DMF might be a therapeutic drug for patients with vascular disease.

  20. SNS-032 Prevents Tumor Cell-Induced Angiogenesis By Inhibiting Vascular Endothelial Growth Factor

    Directory of Open Access Journals (Sweden)

    M. Aktar Ali

    2007-05-01

    Full Text Available Cell proliferation, migration, and capillary network formation of endothelial cells are the fundamental steps for angiogenesis, which involves the formation of new blood vessels. The purpose of this study is to investigate the effect of a novel aminothiazole SNS-032 on these critical steps for in vitro angiogenesis using a coculture system consisting of human umbilical vein endothelial cells (HUVECs and human glioblastoma cells (U87MG. SNS-032 is a potent selective inhibitor of cyclin-dependent kinases 2, 7, and 9, and inhibits both transcription and cell cycle. In this study, we examined the proliferation and viability of HUVECs and U87MG cells in the presence of SNS-032 and observed a dose-dependent inhibition of cellular proliferation in both cell lines. SNS-032 inhibited threedimensional capillary network formations of endothelial cells. In a coculture study, SNS-032 completely prevented U87MG cell-mediated capillary formation of HUVECs. This inhibitor also prevented the migration of HUVECs when cultured alone or cocultured with U87MG cells. In addition, SNS-032 significantly prevented the production of vascular endothelial growth factor (VEGF in both cell lines, whereas SNS-032 was less effective in preventing capillary network formation and migration of endothelial cells when an active recombinant VEGF was added to the medium. In conclusion, SNS-032 prevents in vitro angiogenesis, and this action is attributable to blocking of VEGF.

  1. Effect of Caspase Inhibitor Ac-DEVD-CHO on Apoptosis of Vascular Smooth Muscle Cells Induced by Artesunate

    Directory of Open Access Journals (Sweden)

    Jingwen Zhang

    2014-05-01

    Full Text Available Numerous studies have shown that the proliferation and apoptosis of vascular smooth muscle cells play a key role in restenosis. Artesunate is a triterpenoid with a peroxide structure and its antimalarial, antitumor, and antiangiogenetic activities can inhibit the proliferation and apoptosis of multifarious cells. Apoptosis is caused by the activation of a series of intracellular proteolytic enzymes, among which caspase-dependent apoptosis was the earliest to be recognized. The purpose of this article is to study the effects of caspase-3 inhibitor Ac-DEVD-CHO on proliferation and apoptosis of vascular smooth muscle cells induced by Artesunate and to explore the mechanism of Artesunate-induced apoptosis of vascular smooth muscle cells. By using the method based on methyl thiazolyl tetrazolium to observe the effects of Artesunate on the growth and proliferation of vascular smooth muscle cells; observing the change in cell shape before and after Artesunate administration by transmission electron microscopy; detecting the changes in cell cycle and apoptosis rates before and after drug administration by flow cytometry; detecting the activity of caspase-3 in the caspase apoptosis pathway by the Western Blot method, we found that Artesunate inhibits the growth and proliferation of vascular smooth muscle cells in a dose- and time-dependent manner within the concentration range of 7.5–120 μg/mL, and the inhibition rate of Artesunate can be as high as 89.49 % at a concentration of 120 μg/mL after acting for 72 hours; vascular smooth muscle cells show a typical apoptosis peak due to the effects of higher concentration of Artesunate. Compared with the control group, the higher-concentration group shows major variability, Ac-DEVD-CHO, however, can significantly decrease this induction; it has been detected by Western Blot that Artesunate can induce caspase-3 activity dramatically in vascular smooth muscle cells, but this activation may be remarkably

  2. Thermosensitive chitosan-Pluronic hydrogel as an injectable cell delivery carrier for cartilage regeneration.

    Science.gov (United States)

    Park, Kyung Min; Lee, Sang Young; Joung, Yoon Ki; Na, Jae Sik; Lee, Myung Chul; Park, Ki Dong

    2009-07-01

    Injectable hydrogels have been studied for potential applications for articular cartilage regeneration. In this study, a thermosensitive chitosan-Pluronic (CP) hydrogel was designed as an injectable cell delivery carrier for cartilage regeneration. The CP conjugate was synthesized by grafting Pluronic onto chitosan using EDC/NHS chemistry. The sol-gel phase transition and mechanical properties of the CP hydrogel were examined by rheological experiments. The CP solution underwent a sol-gel transition around 25 degrees C at which the storage modulus (G') approaches 10(4)Pa, highlighting the potential of this material as an injectable scaffold for cartilage regeneration. The CP hydrogel was formed rapidly by increasing the temperature. The morphology of the dried CP hydrogel was observed by scanning electron microscopy. In vitro cell culture was performed using bovine chondrocytes. The proliferation of bovine chondrocytes and the amount of synthesized glycosaminoglycan increased for 28 days. These results suggested that the CP hydrogel has potential as an injectable cell delivery carrier for cartilage regeneration and could serve as a new biomaterial for tissue engineering. PMID:19261553

  3. In vivo vascularization of cell sheets provided better long-term tissue survival than injection of cell suspension.

    Science.gov (United States)

    Takeuchi, Ryohei; Kuruma, Yosuke; Sekine, Hidekazu; Dobashi, Izumi; Yamato, Masayuki; Umezu, Mitsuo; Shimizu, Tatsuya; Okano, Teruo

    2016-08-01

    Cell sheets have shown a remarkable ability for repairing damaged myocardium in clinical and preclinical studies. Although they demonstrate a high degree of viability as engrafted cells in vivo, the reason behind their survivability is unclear. In this study, the survival and vascularization of rat cardiac cell sheets transplanted in the subcutaneous tissue of athymic rats were investigated temporally. The cell sheets showed significantly higher survival than cell suspensions for up to 12 months, using an in vivo bioluminescence imaging system to detect luciferase-positive transplanted cells. Terminal deoxynucleotidyl transferase dUTP nick-end labelling (TUNEL) assay also showed a smaller number of apoptotic cells in the cell sheets than in the cell suspensions at 1 day. Rapid vascular formation and maturation were observed inside the cell sheets using an in vivo imaging system. Leaky vessels appeared at 6 h, red blood cells flowing through functional vessels appeared at 12 h, and morphologically matured vessels appeared at 7 days. In addition, immunostaining of cell sheets with nerve/glial antigen-2 (NG2) showed that vessel maturity increased over time. Interestingly, these results correlated with the dynamics of cell sheet mRNA expression. Genes related to endothelial cells (ECs) proliferation, migration and vessel sprouting were highly expressed within 1 day, and genes related to pericyte recruitment and vessel maturation were highly expressed at 3 days or later. This suggested that the cell sheets could secrete appropriate angiogenic factors in a timely way after transplantation, and this ability might be a key reason for their high survival. Copyright © 2014 John Wiley & Sons, Ltd. PMID:24470393

  4. Grain-boundary-enhanced carrier collection in CdTe solar cells.

    Science.gov (United States)

    Li, Chen; Wu, Yelong; Poplawsky, Jonathan; Pennycook, Timothy J; Paudel, Naba; Yin, Wanjian; Haigh, Sarah J; Oxley, Mark P; Lupini, Andrew R; Al-Jassim, Mowafak; Pennycook, Stephen J; Yan, Yanfa

    2014-04-18

    When CdTe solar cells are doped with Cl, the grain boundaries no longer act as recombination centers but actively contribute to carrier collection efficiency. The physical origin of this remarkable effect has been determined through a combination of aberration-corrected scanning transmission electron microscopy, electron energy loss spectroscopy, and first-principles theory. Cl substitutes for a large proportion of the Te atoms within a few unit cells of the grain boundaries. Density functional calculations reveal the mechanism, and further indicate the grain boundaries are inverted to n type, establishing local p-n junctions which assist electron-hole pair separation. The mechanism is electrostatic, and hence independent of the geometry of the boundary, thereby explaining the universally high collection efficiency of Cl-doped CdTe solar cells. PMID:24785058

  5. Rosiglitzone suppresses angiotensin II-induced production of KLF5 and cell proliferation in rat vascular smooth muscle cells.

    Directory of Open Access Journals (Sweden)

    Dengfeng Gao

    Full Text Available Krüppel-like factor (KLF 5, which initiates vascular smooth muscle cell (VSMC proliferation, also participates in Angiotensin (Ang II-induced vascular remodeling. The protective effect of rosiglitazone on vascular remodeling may be due to their impact on VSMC proliferation. However, the underlying mechanisms involved remain unclear. This study was designed to investigate whether the antiproliferation effects of rosiglitazone are mediated by regulating Ang II/KLF5 response. We found that, in aortas of Ang II-infused rats, vascular remodeling and KLF5 expression were markedly increased, and its target gene cyclin D1 was overexpressed. Co-treatment with rosiglitazone diminished these changes. In growth-arrested VSMCs, PPAR-γ agonists (rosiglitazone and 15d-PGJ2 dose-dependently inhibited Ang II-induced cell proliferation and expression of KLF5 and cyclin D1. Moreover, these effects were attenuated by the PPAR-γ antagonists GW9662, bisphenol A diglycidyl ether and PPAR-γ specific siRNA. Furthermore, rosiglitazone inhibited Ang II-induced phosphorylation of protein kinase C (PKC ζ and extracellular signal-regulated kinase (ERK 1/2 and activation of early growth response protein (Egr. In conclusion, in Ang II-stimulated VSMCs, rosiglitazone might have an antiproliferative effect through mechanisms that include reducing KLF5 expression, and a crosstalk between PPAR-γ and PKCζ/ERK1/2/Egr may be involved in. These findings not only provide a previously unrecognized mechanism by which PPAR-γ agonists inhibit VSMC proliferation, but also document a novel evidence for the beneficial vascular effect of PPAR-γ activation.

  6. Rosiglitzone Suppresses Angiotensin II-Induced Production of KLF5 and Cell Proliferation in Rat Vascular Smooth Muscle Cells

    Science.gov (United States)

    Gao, Dengfeng; Hao, Guanghua; Meng, Zhe; Ning, Ning; Yang, Guang; Liu, Zhongwei; Dong, Xin; Niu, Xiaolin

    2015-01-01

    Krüppel-like factor (KLF) 5, which initiates vascular smooth muscle cell (VSMC) proliferation, also participates in Angiotensin (Ang) II-induced vascular remodeling. The protective effect of rosiglitazone on vascular remodeling may be due to their impact on VSMC proliferation. However, the underlying mechanisms involved remain unclear. This study was designed to investigate whether the antiproliferation effects of rosiglitazone are mediated by regulating Ang II/KLF5 response. We found that, in aortas of Ang II-infused rats, vascular remodeling and KLF5 expression were markedly increased, and its target gene cyclin D1 was overexpressed. Co-treatment with rosiglitazone diminished these changes. In growth-arrested VSMCs, PPAR-γ agonists (rosiglitazone and 15d-PGJ2) dose-dependently inhibited Ang II-induced cell proliferation and expression of KLF5 and cyclin D1. Moreover, these effects were attenuated by the PPAR-γ antagonists GW9662, bisphenol A diglycidyl ether and PPAR-γ specific siRNA. Furthermore, rosiglitazone inhibited Ang II-induced phosphorylation of protein kinase C (PKC) ζ and extracellular signal-regulated kinase (ERK) 1/2 and activation of early growth response protein (Egr). In conclusion, in Ang II-stimulated VSMCs, rosiglitazone might have an antiproliferative effect through mechanisms that include reducing KLF5 expression, and a crosstalk between PPAR-γ and PKCζ/ERK1/2/Egr may be involved in. These findings not only provide a previously unrecognized mechanism by which PPAR-γ agonists inhibit VSMC proliferation, but also document a novel evidence for the beneficial vascular effect of PPAR-γ activation. PMID:25874449

  7. 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.

  8. Preserved vascular integrity and enhanced survival following neuropilin-1 inhibition in a mouse model of CD8 T cell-initiated CNS vascular permeability

    Directory of Open Access Journals (Sweden)

    Suidan Georgette L

    2012-09-01

    Full Text Available Abstract Background Altered permeability of the blood–brain barrier (BBB is a feature of numerous neurological conditions including multiple sclerosis, cerebral malaria, viral hemorrhagic fevers and acute hemorrhagic leukoencephalitis. Our laboratory has developed a murine model of CD8 T cell-initiated central nervous system (CNS vascular permeability in which vascular endothelial growth factor (VEGF signaling plays a prominent role in BBB disruption. Findings In this study, we addressed the hypothesis that in vivo blockade of VEGF signal transduction through administration of peptide (ATWLPPR to inhibit neuropilin-1 (NRP-1 would have a therapeutic effect following induction of CD8 T cell-initiated BBB disruption. We report that inhibition of NRP-1, a co-receptor that enhances VEGFR2 (flk-1 receptor activation, decreases vascular permeability, brain hemorrhage, and mortality in this model of CD8 T cell-initiated BBB disruption. We also examine the expression pattern of VEGFR2 (flk-1 and VEGFR1 (flt-1 mRNA expression during a time course of this condition. We find that viral infection of the brain leads to increased expression of flk-1 mRNA. In addition, flk-1 and flt-1 expression levels decrease in the striatum and hippocampus in later time points following induction of CD8 T cell-mediated BBB disruption. Conclusion This study demonstrates that NRP-1 is a potential therapeutic target in neuro-inflammatory diseases involving BBB disruption and brain hemorrhage. Additionally, the reduction in VEGF receptors subsequent to BBB disruption could be involved in compensatory negative feedback as an attempt to reduce vascular permeability.

  9. 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

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

    International Nuclear Information System (INIS)

    Highlights: ► Chemerin is a novel adipocytokine with almost unknown function in vasculature. ► Chemerin activates Akt/eNOS/NO pathways in endothelial cells. ► Chemerin inhibits TNF-α-induced monocyte adhesion to endothelial cells. ► Chemerin inhibits TNF-induced VCAM-1 via suppressing NF-κB and p38 signal. ► 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)-κB p65 (Ser536) and p38 as well as vascular cell adhesion molecule (VCAM)-1 expression induced by tumor necrosis factor (TNF)-α (5 ng/ml, 20 min–6 h). Inhibitor of NF-κB or p38 significantly inhibited the TNF-α-induced VCAM-1 expression. Chemerin also inhibited TNF-α-induced VCAM-1 expression in rat isolated aorta. Moreover, chemerin significantly inhibited monocytes adhesion to TNF-α-stimulated endothelial cells. The inhibitory effect of chemerin on TNF-α-induced VCAM-1 was reversed by a NOS inhibitor. Conversely, an NO donor, sodium nitroprusside significantly inhibited TNF-α-induced VCAM-1. The present results for the first time demonstrate that chemerin plays anti-inflammatory roles by preventing TNF-α-induced VCAM-1 expression and monocytes adhesion in vascular endothelial cells. The effect is mediated via inhibiting activation of NF-κB and p38 through stimulation of Akt/eNOS signaling and NO production.

  11. "The preadipocyte factor" DLK1 marks adult mouse adipose tissue residing vascular cells that lack in vitro adipogenic differentiation potential

    DEFF Research Database (Denmark)

    Andersen, Ditte Caroline; Jensen, Line; Schrøder, Henrik Daa;

    2009-01-01

    Delta-like 1 (Dlk1) is expressed in 3T3-L1 preadipocytes and has frequently been referred to as "the" preadipocyte marker, yet the phenotype of DLK1(+) cells in adipose tissue remains undetermined. Herein, we demonstrate that DLK1(+) cells encompass around 1-2% of the adult mouse adipose stromal...... vascular fraction (SVF). Unexpectedly, the DLK1(+)SVF population was enriched for cells expressing genes generally ascribed to the vascular lineage and did not possess any adipogenic differentiation potential in vitro. Instead, DLK1(+) cells comprised an immediate ability for cobblestone formation......, generation of tube-like structures on matrigel, and uptake of Acetylated Low Density-Lipoprotein, all characteristics of endothelial cells. We therefore suggest that DLK1(+)SVF cells are of a vascular origin and not them-selves committed preadipocytes as assumed hitherto....

  12. Arachidonic metabolism and radiation toxicity in cultures of vascular endothelial cells

    Energy Technology Data Exchange (ETDEWEB)

    Eldor, A.; Vlodavsky, I.; Fuks, Z.; Matzner, Y.; Rubin, D.B. (Hadassah Univ. Hospital, Jerusalem (Israel) Rush-Presbyterian-St. Luke' s Medical Center, Chicago, IL (USA))

    1989-06-01

    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{sub 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).

  13. Enhanced Viability of Endothelial Colony Forming Cells in Fibrin Microbeads for Sensor Vascularization

    Directory of Open Access Journals (Sweden)

    Jarel K. Gandhi

    2015-09-01

    Full Text Available Enhanced vascularization at sensor interfaces can improve long-term function. Fibrin, a natural polymer, has shown promise as a biomaterial for sensor coating due to its ability to sustain endothelial cell growth and promote local vascularization. However, the culture of cells, particularly endothelial cells (EC, within 3D scaffolds for more than a few days is challenging due to rapid loss of EC viability. In this manuscript, a robust method for developing fibrin microbead scaffolds for long-term culture of encapsulated ECs is described. Fibrin microbeads are formed using sodium alginate as a structural template. The size, swelling and structural properties of the microbeads were varied with needle gauge and composition and concentration of the pre-gel solution. Endothelial colony-forming cells (ECFCs were suspended in the fibrin beads and cultured within a perfusion bioreactor system. The perfusion bioreactor enhanced ECFCs viability and genome stability in fibrin beads relative to static culture. Perfusion bioreactors enable 3D culture of ECs within fibrin beads for potential application as a sensor coating.

  14. Adipose-Derived Stromal Vascular Fraction Cell Effects on a Rodent Model of Thin Endometrium.

    Directory of Open Access Journals (Sweden)

    Robert K Hunter

    Full Text Available Endometrial dysfunction affects approximately 1% of infertile women, and there is currently no standard therapy for improving fertility treatment outcomes in these patients. In our study, we utilized a rodent model of thin endometrium to test whether intrauterine application of adipose-derived stromal vascular fraction cells (SVF could improve morphological and physiological markers of endometrial receptivity. Using anhydrous ethanol, endometrial area and gland density were significantly reduced in our model of thin endometrium. Application of SVF was associated with a 29% reduction in endometrial vascular endothelial growth factor (VEGF expression and significant increases in uterine artery systolic/diastolic velocity ratios and resistance index values, suggesting reduced diastolic microvascular tone. However, no significant improvements in endometrial area or gland density were observed following SVF treatment. 3D confocal imaging demonstrated poor engraftment of SVF cells into recipient tissue, which likely contributed to the negative results of this study. We suspect modified treatment protocols utilizing adjuvant estrogen and/or tail vein cell delivery may improve SVF retention and therapeutic response in subsequent studies. SVF is an easily-obtainable cell product with regenerative capability that may have a future role in the treatment of infertile women with endometrial dysfunction.

  15. Temperature and nucleotide dependence of calcium release by myo-inositol 1,4,5-trisphosphate in cultured vascular smooth muscle cells

    International Nuclear Information System (INIS)

    Inositol 1,4,5-trisphosphate (IP3) rapidly increased 45Ca2+ efflux from a nonmitochondrial organelle in cultured vascular smooth muscle cells that were permeabilized with saponin. A nucleotide, preferably ATP, was essential for IP3-evoked 45Ca2+ release. Two nonhydrolyzable ATP analogues satisfied the nucleotide requirement for IP3-evoked 45Ca2+ release. IP3 strongly stimulated 45Ca2+ efflux at low temperatures (1 to 15 degrees C). Decreasing the temperature from 37 to 4 degrees C inhibited the rate of IP3-stimulated efflux by only about 33%. The failure of such low temperatures to strongly inhibit IP3-induced 45Ca2+ efflux suggests that IP3 activated a Ca2+ channel, rather than a carrier, by a ligand-binding, rather than a metabolic, reaction

  16. Temperature and nucleotide dependence of calcium release by myo-inositol 1,4,5-trisphosphate in cultured vascular smooth muscle cells

    Energy Technology Data Exchange (ETDEWEB)

    Smith, J.B.; Smith, L.; Higgins, B.L.

    1985-11-25

    Inositol 1,4,5-trisphosphate (IP3) rapidly increased UVCaS efflux from a nonmitochondrial organelle in cultured vascular smooth muscle cells that were permeabilized with saponin. A nucleotide, preferably ATP, was essential for IP3-evoked UVCaS release. Two nonhydrolyzable ATP analogues satisfied the nucleotide requirement for IP3-evoked UVCaS release. IP3 strongly stimulated UVCaS efflux at low temperatures (1 to 15 degrees C). Decreasing the temperature from 37 to 4 degrees C inhibited the rate of IP3-stimulated efflux by only about 33%. The failure of such low temperatures to strongly inhibit IP3-induced UVCaS efflux suggests that IP3 activated a CaS channel, rather than a carrier, by a ligand-binding, rather than a metabolic, reaction.

  17. Induction of vascular endothelial phenotype and cellular proliferation from human cord blood stem cells cultured in simulated microgravity

    Science.gov (United States)

    Chiu, Brian; Z-M Wan, Jim; Abley, Doris; Akabutu, John

    2005-05-01

    Recent studies have demonstrated that stem cells derived from adult hematopoietic tissues are capable of trans-differentiation into non-hematopoietic cells, and that the culture in microgravity ( μg) may modulate the proliferation and differentiation. We investigated the application of μg to human umbilical cord blood stem cells (CBSC) in the induction of vascular endothelial phenotype expression and cellular proliferation. CD34+ mononuclear cells were isolated from waste human umbilical cord blood samples and cultured in simulated μg for 14 days. The cells were seeded in rotary wall vessels (RWV) with or without microcarrier beads (MCB) and vascular endothelial growth factor was added during culture. Controls consisted of culture in 1 G. The cell cultures in RWV were examined by inverted microscopy. Cell counts, endothelial cell and leukocyte markers performed by flow-cytometry and FACS scan were assayed at days 1, 4, 7 and at the termination of the experiments. Culture in RWV revealed significantly increased cellular proliferation with three-dimensional (3D) tissue-like aggregates. At day 4, CD34+ cells cultured in RWV bioreactor without MCB developed vascular tubular assemblies and exhibited endothelial phenotypic markers. These data suggest that CD34+ human umbilical cord blood progenitors are capable of trans-differentiation into vascular endothelial cell phenotype and assemble into 3D tissue structures. Culture of CBSC in simulated μg may be potentially beneficial in the fields of stem cell biology and somatic cell therapy.

  18. Molecular mechanisms and cell signaling of 20-hydroxyeicosatetraenoic acid in vascular pathophysiology.

    Science.gov (United States)

    Fan, Fan; Ge, Ying; Lv, Wenshan; Elliott, Matthew R; Muroya, Yoshikazu; Hirata, Takashi; Booz, George W; Roman, Richard J

    2016-01-01

    Cytochrome P450s enzymes catalyze the metabolism of arachidonic acid to epoxyeicosatrienoic acids (EETs), dihydroxyeicosatetraenoic acid and hydroxyeicosatetraeonic acid (HETEs). 20-HETE is a vasoconstrictor that depolarizes vascular smooth muscle cells by blocking K+ channels. EETs serve as endothelial derived hyperpolarizing factors. Inhibition of the formation of 20-HETE impairs the myogenic response and autoregulation of renal and cerebral blood flow. Changes in the formation of EETs and 20-HETE have been reported in hypertension and drugs that target these pathways alter blood pressure in animal models. Sequence variants in CYP4A11 and CYP4F2 that produce 20-HETE, UDP-glucuronosyl transferase involved in the biotransformation of 20-HETE and soluble epoxide hydrolase that inactivates EETs are associated with hypertension in human studies. 20-HETE contributes to the regulation of vascular hypertrophy, restenosis, angiogenesis and inflammation. It also promotes endothelial dysfunction and contributes to cerebral vasospasm and ischemia-reperfusion injury in the brain, kidney and heart. This review will focus on the role of 20-HETE in vascular dysfunction, inflammation, ischemic and hemorrhagic stroke and cardiac and renal ischemia reperfusion injury. PMID:27100515

  19. Protective effect of atorvastatin on radiation-induced vascular endothelial cell injury in vitro

    International Nuclear Information System (INIS)

    Vascular endothelial cells are very sensitive to ionizing radiation, and it is important to develop effective prevent agents and measures in radiation exposure protection. In the present study, the protective effects of atorvastatin on irradiated human umbilical vein endothelial cells (HUVEC) and the possible mechanisms were explored. Cultured HUVEC were treated by atorvastatin at a final concentration of 10 μmol/ml for 10 minutes, and then irradiated at a dose of 2 Gy or 25 Gy. Twenty-four hours after irradiation, apoptosis of HUVEC was monitored by flow cytometry, and the expression of thrombomodulin (TM) and protein C activation in HUVEC was respectively assessed by flow cytometry and spectrophotometry. After treatment with atorvastatin for 24 h, the rate of cell apoptosis decreased by 6% and 16% in cells irradiated with 2 Gy and 25 Gy, respectively. TM expression increased by 77%, 59%, and 61% in untreated cells, 2 Gy irradiation-treated cells, and 25 Gy irradiation-treated cells, respectively. The protein C levels in 2 Gy and 25 Gy irradiation-treated cells were reduced by 23% and 34% when compared with untreated cells, but up-regulated by 79% and 76% when compared with cells which were irradiated and treated with atorvastatin. In conclusion, these data indicate that atorvastatin exerts protective effects on irradiated HUVEC by reducing apoptosis by up-regulating TM expression and enhancing protein C activation in irradiated HUVEC. (author)

  20. Encapsulating Mobile Proton Carriers into Structural Defects in Coordination Polymer Crystals: High Anhydrous Proton Conduction and Fuel Cell Application.

    Science.gov (United States)

    Inukai, Munehiro; Horike, Satoshi; Itakura, Tomoya; Shinozaki, Ryota; Ogiwara, Naoki; Umeyama, Daiki; Nagarkar, Sanjog; Nishiyama, Yusuke; Malon, Michal; Hayashi, Akari; Ohhara, Takashi; Kiyanagi, Ryoji; Kitagawa, Susumu

    2016-07-13

    We describe the encapsulation of mobile proton carriers into defect sites in nonporous coordination polymers (CPs). The proton carriers were encapsulated with high mobility and provided high proton conductivity at 150 °C under anhydrous conditions. The high proton conductivity and nonporous nature of the CP allowed its application as an electrolyte in a fuel cell. The defects and mobile proton carriers were investigated using solid-state NMR, XAFS, XRD, and ICP-AES/EA. On the basis of these analyses, we concluded that the defect sites provide space for mobile uncoordinated H3PO4, H2PO4(-), and H2O. These mobile carriers play a key role in expanding the proton-hopping path and promoting the mobility of protons in the coordination framework, leading to high proton conductivity and fuel cell power generation. PMID:27324658

  1. The development of blood-retinal barrier during the interaction of astrocytes with vascular wall cells

    Institute of Scientific and Technical Information of China (English)

    Huanling Yao; Tianshi Wang; Jiexin Deng; Ding Liu; Xiaofei Li; Jinbo Deng

    2014-01-01

    Astrocytes are intimately involved in the formation and development of retinal vessels. Astrocyte dysfunction is a major cause of blood-retinal barrier injury and other retinal vascular diseases. In this study, the development of the retinal vascular system and the formation of the blood-ret-inal barrier in mice were investigated using immunolfuorescence staining, gelatin-ink perfusion, and transmission electron microscopy. The results showed that the retinal vascular system of mice develops from the optic disc after birth, and radiates out gradually to cover the entire retina, taking the papilla optica as the center. First, the superifcial vasculature is formed on the inner retinal layer;then, the vasculature extends into the inner and outer edges of the retinal inner nuclear layer, forming the deep vasculature that is parallel to the superifcial vasculature. The blood-retinal barrier is mainly composed of endothelium, basal lamina and the end-feet of astrocytes, which become mature during mouse development. Initially, the naive endothelial cells were immature with few organelles and many microvilli. The basal lamina was uniform in thickness, and the glial end-feet surrounded the outer basal lamina incompletely. In the end, the blood-retinal barrier matures with smooth endothelia connected through tight junctions, rela-tively thin and even basal lamina, and relatively thin glial cell end-feet. These ifndings indicate that the development of the vasculature in the retina follows the rules of“center to periphery”and“superifcial layer to deep layers”. Its development and maturation are spatially and tempo-rally consistent with the functional performance of retinal neurons and photosensitivity. The blood-retinal barrier gradually becomes mature via the process of interactions between astro-cytes and blood vessel cells.

  2. Regulation of SIRT1 in vascular smooth muscle cells from streptozotocin-diabetic rats.

    Directory of Open Access Journals (Sweden)

    Alice Toniolo

    Full Text Available Sirtuins enzymes are a conserved family of nicotinamide adenine dinucleotide (NAD-dependent deacetylases and ADP-ribosyltransferases that mediate responses to oxidative stress, fasting and dietary restriction in mammals. Vascular smooth muscle cells (VSMCs are involved in many mechanisms that regulate vascular biology in vivo but the role of SIRT1 has not been explored in much detail. Therefore, we investigated the regulation of SIRT1 in cultured VSMCs under various stress conditions including diabetes. Sprague-Dawley rats were made diabetic by injecting a single dose of streptozotocin (65 mg/Kg, and aortic VSMCs were isolated after 4 weeks. Immunocytochemistry showed that SIRT1 was localized predominantly in the nucleus, with lower staining in VSMCs from STZ-diabetic as compared with normoglycemic rats. Previous diabetes induction in vivo and high glucose concentrations in vitro significantly downregulated SIRT1 amounts as detected in Western blot assays, whereas TNF-α (30 ng/ml stimulation failed to induce significant changes. Because estrogen signaling affects several pathways of oxidative stress control, we also investigated SIRT1 modulation by 17β-estradiol. Treatment with the hormone (10 nM or a selective estrogen receptor-α agonist decreased SIRT1 levels in VSMCs from normoglycemic but not in those from STZ-diabetic animals. 17β-estradiol treatment also enhanced activation of AMP-dependent kinase, which partners with SIRT1 in a signaling axis. SIRT1 downregulation by 17β-estradiol could be observed as well in human peripheral blood mononuclear cells, a cell type in which SIRT1 downregulation is associated with insulin resistance and subclinical atherosclerosis. These data suggest that SIRT1 protein levels are regulated by diverse cellular stressors to a variable extent in VSMCs from diabetic and normoglycemic rats, warranting further investigation on SIRT1 as a modulator of VSMC activity in settings of vascular inflammation.

  3. Increased expression of granulocyte colony-stimulating factor mediates mesenchymal stem cells recruitment after vascular injury

    Institute of Scientific and Technical Information of China (English)

    ZHAO Yong; LIU Ying-xi; XIEShuang-lun; DENG Bing-qing; WANG Jing-feng; NIE Ru-qiong

    2011-01-01

    Background Recent studies indicate that bone marrow-derived cells may significantly contribute to atherosclerosis,post-angioplasty restenosis and transplantation-associated vasculopathy.The responsible bone marrow (BM) cells and mechanisms regulating the mobilization of these cells are currently unclear.The purpose of this study was to investigate the expression of granulocyte colony-stimulating factor (G-CSF) on injured arteries and its effects on mesenchymal stem cells (MSCs) differentiation into vascular smooth muscle cells (VSMCs) in the process of vascular remodeling.Methods Balloon-mediated vascular injury was established in female rats (n=1O0) which received radioprotective whole female BM cells by tail vein injection and male MSCs through a tibial BM injection after lethal irradiation.The injured and contralateral carotid arteries were harvested at 3,7,14 and 28 days after treatment.Results Morphometric analysis indicated that intima to media area-ratio (I/M ratio) significantly increased at 28 days,0.899±-0.057 (P <0.01),compared with uninjured arteries.Combining fluorescence in situ hybridization (FISH) and immunohistochemical analysis showed that a significant number of the neointimal cells derived from MSCs,(45.2±8.5)% at 28 days (P=0.01),compared with (23.5±6.3)% at 14 days.G-CSF was induced in carotid arteries subject to balloon angioplasty (fold mRNA change=8.67±0.63 at three days,relative G-CSF protein=0.657±-0.011 at three days,P <0.01,respectively,compared with uninjured arteries).G-CSF was chemotactic for MSCs but did not affect the differentiation of MSCs into smooth-muscle-like cells.Conclusion Increased expression of G-CSF by injured arteries plays an essential role in contribution to recruitment and homing of MSCs to the site of the arterial lesion.

  4. Autonomous Precision Spraying Trials Using a Novel Cell Spray Implement Mounted on an Armadillo Tool Carrier

    DEFF Research Database (Denmark)

    Jensen, Kjeld; Stigaard Laursen, Morten; Midtiby, Henrik;

    Precision weeding is one of the most promising applications for autonomous service robots in biological production. Herbicides have been the default weeding solution during the past decades, but there is a growing concern about the environmental impact on drinking water reservoirs etc. The use...... of computer vision and precision spraying technology makes it possible to significantly reduce the consumption of herbicides. The work presented here is part of a project with the purpose of performing autonomous precision spraying trials. In this work a novel cell sprayer designed for large scale tests...... with an Armadillo robotic tool carrier consisting of two battery powered track modules mounted on each side of the implement. This paper focus on the cell sprayer implement design including camera system, sprayer module and integration with the service robot and the robot software. The FroboMind software platform...

  5. Drug loading and release on tumor cells using silk fibroin–albumin nanoparticles as carriers

    International Nuclear Information System (INIS)

    Polymeric and biodegradable nanoparticles are frequently used in drug delivery systems. In this study silk fibroin–albumin blended nanoparticles were prepared using the desolvation method without any surfactant. These nanoparticles are easily internalized by the cells, reside within perinuclear spaces and act as carriers for delivery of the model drug methotrexate. Methotrexate loaded nanoparticles have better encapsulation efficiency, drug loading ability and less toxicity. The in vitro release behavior of methotrexate from the nanoparticles suggests that about 85% of the drug gets released after 12 days. The encapsulation and loading of a drug would depend on factors such as size, charge and hydrophobicity, which affect drug release. MTT assay and conjugation of particles with FITC demonstrate that the silk fibroin–albumin nanoparticles do not affect the viability and biocompatibility of cells. This blended nanoparticle, therefore, could be a promising nanocarrier for the delivery of drugs and other bioactive molecules. (paper)

  6. Mononuclear Phagocyte-Derived Microparticulate Caspase-1 Induces Pulmonary Vascular Endothelial Cell Injury.

    Directory of Open Access Journals (Sweden)

    Srabani Mitra

    Full Text Available Lung endothelial cell apoptosis and injury occurs throughout all stages of acute lung injury (ALI/ARDS and impacts disease progression. Lung endothelial injury has traditionally been focused on the role of neutrophil trafficking to lung vascular integrin receptors induced by proinflammatory cytokine expression. Although much is known about the pathogenesis of cell injury and death in ALI/ARDS, gaps remain in our knowledge; as a result of which there is currently no effective pharmacologic therapy. Enzymes known as caspases are essential for completion of the apoptotic program and secretion of pro-inflammatory cytokines. We hypothesized that caspase-1 may serve as a key regulator of human pulmonary microvascular endothelial cell (HPMVEC apoptosis in ALI/ARDS. Our recent experiments confirm that microparticles released from stimulated monocytic cells (THP1 induce lung endothelial cell apoptosis. Microparticles pretreated with the caspase-1 inhibitor, YVAD, or pan-caspase inhibitor, ZVAD, were unable to induce cell death of HPMVEC, suggesting the role of caspase-1 or its substrate in the induction of HPMVEC cell death. Neither un-induced microparticles (control nor direct treatment with LPS induced apoptosis of HPMVEC. Further experiments showed that caspase-1 uptake into HPMVEC and the induction of HPMVEC apoptosis was facilitated by caspase-1 interactions with microparticulate vesicles. Altering vesicle integrity completely abrogated apoptosis of HPMVEC suggesting an encapsulation requirement for target cell uptake of active caspase-1. Taken together, we confirm that microparticle centered caspase-1 can play a regulator role in endothelial cell injury.

  7. Antisense oligodeoxynucleotide inhibits vascular endothelial growth factor expression in U937 foam cells

    Institute of Scientific and Technical Information of China (English)

    YANGPeng-Yuan; RUIYao-Cheng; JINYou-Xin; LITie-Jun; QIUYan; ZHANGLi; WANGJie-Song

    2003-01-01

    AIM:To study the expression of vascular endothelial growth factor (VEGF) induced by oxidized low density liprotein (ox-LDL) and the inhibitory effects of antisense oligodeoxynucleotide (asODN) on the levels of VEGF protein and mRNA in the U937 foam cells. METHODS: U937 cells were incubated with ox-LDL 80 mg/L for 48h, then ,the foam cells were treated with asODN (0,5,10, and 20μmol/L). The VEGF concentration in the media was determined by ELISA. The VEGF protein expression level in cells was measured by immuohistochemistry; the positive ratio detected by a morphometrical analysis system was used as the amount of the VEGF expression level. The VEGF mRNA level was examined by Northern blotting. RESULTS: After U937 cells were incubated with ox-LDL, VEGF expression level increased greatly both in the cells and in the media. asODN markeldy inhibited the increase of VEGF. After treatment with asODN 20μmol/L, the VEGF protein concentration in the media decreased by 45.0%, the VEGF positive ratio detected by immuohistochemistry in cells decreased by 64.9%, and the VEGF mRNA level decreased by 47.1%. CONCLUSION: The expression of VEGF in U937 foam cells was strong. asODN inhibited VEGF expression significantly in U937 foam cells in vitro.

  8. Hydrogen peroxide as a sustainable energy carrier: Electrocatalytic production of hydrogen peroxide and the fuel cell

    International Nuclear Information System (INIS)

    This review describes homogeneous and heterogeneous catalytic reduction of dioxygen with metal complexes focusing on the catalytic two-electron reduction of dioxygen to produce hydrogen peroxide. Whether two-electron reduction of dioxygen to produce hydrogen peroxide or four-electron O2-reduction to produce water occurs depends on the types of metals and ligands that are utilized. Those factors controlling the two processes are discussed in terms of metal–oxygen intermediates involved in the catalysis. Metal complexes acting as catalysts for selective two-electron reduction of oxygen can be utilized as metal complex-modified electrodes in the electrocatalytic reduction to produce hydrogen peroxide. Hydrogen peroxide thus produced can be used as a fuel in a hydrogen peroxide fuel cell. A hydrogen peroxide fuel cell can be operated with a one-compartment structure without a membrane, which is certainly more promising for the development of low-cost fuel cells as compared with two compartment hydrogen fuel cells that require membranes. Hydrogen peroxide is regarded as an environmentally benign energy carrier because it can be produced by the electrocatalytic two-electron reduction of O2, which is abundant in air, using solar cells; the hydrogen peroxide thus produced could then be readily stored and then used as needed to generate electricity through the use of hydrogen peroxide fuel cells.

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

    OpenAIRE

    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-pol...

  10. Parents' responses to receiving sickle cell or cystic fibrosis carrier results for their child following newborn screening.

    Science.gov (United States)

    Ulph, Fiona; Cullinan, Tim; Qureshi, Nadeem; Kai, Joe

    2015-04-01

    Universal newborn screening for sickle cell disorders and cystic fibrosis aims to enable the early identification and treatment of affected babies. Screening can also identify infants who are healthy carriers, with carrier results being the commonest outcome for parents and professionals to discuss in practice. However it is unclear what the effect will be on parents on being informed of their baby's carrier result. Semi-structured face-to-face interviews were conducted with a purposeful sample of 67 family members (49 mothers, 16 fathers, 2 grandparents) of 51 infants identified by universal newborn screening as carriers of cystic fibrosis (n=27) and sickle cell (n=24), across all health regions in England. Data were analysed by thematic analysis with subsequent respondent validation. Untoward anxiety or distress among parents appeared influenced by how results were conveyed, rather than the carrier result per se. Parents who had more prior awareness of carrier status or the possibility of a carrier result assimilated the information more readily. Being left in an information vacuum while awaiting results, or before seeing a professional, led some parents to fear that their child had a serious health condition. Parental distress and anxiety appeared mostly transient, subsiding with understanding of carrier status and communication with a professional. Parents regarded carrier results as valuable information and sought to share this with their families and to inform their children in the future. However parents needed greater support after communication of results in considering and accessing cascade testing, and negotiating further communication within their families. PMID:25005733

  11. Parents' responses to receiving sickle cell or cystic fibrosis carrier results for their child following newborn screening

    Science.gov (United States)

    Ulph, Fiona; Cullinan, Tim; Qureshi, Nadeem; Kai, Joe

    2015-01-01

    Universal newborn screening for sickle cell disorders and cystic fibrosis aims to enable the early identification and treatment of affected babies. Screening can also identify infants who are healthy carriers, with carrier results being the commonest outcome for parents and professionals to discuss in practice. However it is unclear what the effect will be on parents on being informed of their baby's carrier result. Semi-structured face-to-face interviews were conducted with a purposeful sample of 67 family members (49 mothers, 16 fathers, 2 grandparents) of 51 infants identified by universal newborn screening as carriers of cystic fibrosis (n=27) and sickle cell (n=24), across all health regions in England. Data were analysed by thematic analysis with subsequent respondent validation. Untoward anxiety or distress among parents appeared influenced by how results were conveyed, rather than the carrier result per se. Parents who had more prior awareness of carrier status or the possibility of a carrier result assimilated the information more readily. Being left in an information vacuum while awaiting results, or before seeing a professional, led some parents to fear that their child had a serious health condition. Parental distress and anxiety appeared mostly transient, subsiding with understanding of carrier status and communication with a professional. Parents regarded carrier results as valuable information and sought to share this with their families and to inform their children in the future. However parents needed greater support after communication of results in considering and accessing cascade testing, and negotiating further communication within their families. PMID:25005733

  12. Preparation of open porous polycaprolactone microspheres and their applications as effective cell carriers in hydrogel system

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Qingchun [Key Laboratory for Ultrafine Materials of Ministry of Education, School of Materials Science and Engineering (China); Tan, Ke; Ye, Zhaoyang [State Key Laboratory of Bioreactor Engineering, School of Bioengineering, East China University of Science and Technology, Shanghai, 200237 China (China); Zhang, Yan, E-mail: zhang_yan@ecust.edu.cn [Key Laboratory for Ultrafine Materials of Ministry of Education, School of Materials Science and Engineering (China); Tan, Wensong [State Key Laboratory of Bioreactor Engineering, School of Bioengineering, East China University of Science and Technology, Shanghai, 200237 China (China); Lang, Meidong, E-mail: mdlang@ecust.edu.cn [Key Laboratory for Ultrafine Materials of Ministry of Education, School of Materials Science and Engineering (China)

    2012-12-01

    Common hydrogel, composed of synthetic polymers or natural polysaccharides could not support the adhesion of anchorage-dependent cells due to the lack of cell affinitive interface and high cell constraint. The use of porous polyester microspheres as cell-carriers and introduction of cell-loaded microspheres into the hydrogel system might overcome the problem. However, the preparation of the open porous microsphere especially using polycaprolactone (PCL) has been rarely reported. Here, the open porous PCL microspheres were fabricated via the combined emulsion/solvent evaporation and particle leaching method. The microspheres exhibited porous surface and inter-connective pore structure. Additionally, the pore structure could be easily controlled by adjusting the processing parameters. The surface pore size could be altered from 20 {mu}m to 80 {mu}m and the internal porosities were varied from 30% to 70%. The obtained microspheres were evaluated to delivery mesenchymal stem cells (MSCs) and showed the improved cell adhesion and growth when compared with the non-porous microspheres. Then, the MSCs loaded microspheres were introduced into agarose hydrogel. MSCs remained alive and sustained proliferation in microsphere/agarose composite in 5-day incubation while a decrement of MSCs viabilities was found in agarose hydrogel without microspheres. The results indicated that the microsphere/hydrogel composite had a great potential in cell therapy and injectable system for tissue regeneration. Highlights: Black-Right-Pointing-Pointer The open porous polycaprolactone microspheres were fabricated using paraffin as a porogen. Black-Right-Pointing-Pointer The microspheres exhibited porous surface and inter-connective pore structure. Black-Right-Pointing-Pointer The surface and internal pore size and porosity of microsphere could be controlled. Black-Right-Pointing-Pointer The porous microspheres exhibited an improved cell adhesion and proliferation. Black

  13. The pyrimidine nucleotide carrier PNC1 and mitochondrial trafficking of thymidine phosphates in cultured human cells

    Energy Technology Data Exchange (ETDEWEB)

    Franzolin, Elisa; Miazzi, Cristina; Frangini, Miriam; Palumbo, Elisa; Rampazzo, Chiara [Department of Biology, University of Padova, Via Ugo Bassi 58B, I-35131 Padova (Italy); Bianchi, Vera, E-mail: vbianchi@bio.unipd.it [Department of Biology, University of Padova, Via Ugo Bassi 58B, I-35131 Padova (Italy)

    2012-10-15

    In cycling cells cytosolic de novo synthesis of deoxynucleotides is the main source of precursors for mitochondrial (mt) DNA synthesis. The transfer of deoxynucleotides across the inner mt membrane requires protein carriers. PNC1, a SLC25 family member, exchanges pyrimidine nucleoside triphosphates in liposomes and its downregulation decreases mtUTP concentration in cultured cells. By an isotope-flow protocol we confirmed transport of uridine nucleotides by PNC1 in intact cultured cells and investigated PNC1 involvement in the mt trafficking of thymidine phosphates. Key features of our approach were the manipulation of PNC1 expression by RNA interference or inducible overexpression, the employment of cells proficient or deficient for cytosolic thymidine kinase (TK1) to distinguish the direction of flow of thymidine nucleotides across the mt membrane during short pulses with [{sup 3}H]-thymidine, the determination of mtdTTP specific radioactivity to quantitate the rate of mtdTTP export to the cytoplasm. Downregulation of PNC1 in TK1{sup -} cells increased labeled dTTP in mitochondria due to a reduced rate of export. Overexpression of PNC1 in TK1{sup +} cells increased mtdTTP pool size and radioactivity, suggesting an involvement in the import of thymidine phosphates. Thus PNC1 is a component of the network regulating the mtdTTP pool in human cells. -- Highlights: Black-Right-Pointing-Pointer Thymidine phosphates exchange between mitochondria and cytosol in mammalian cells. Black-Right-Pointing-Pointer siRNA-downregulation of PNC1 delays mitochondrial dTTP export in TK1{sup -} cells. Black-Right-Pointing-Pointer PNC1 overexpression accumulates dTTP in mitochondria of TK1{sup +} cells. Black-Right-Pointing-Pointer PNC1 exchanges thymidine nucleotides across the mitochondrial inner membrane. Black-Right-Pointing-Pointer PNC1 participates in the regulation of the mtdTTP pool supporting mtDNA synthesis.

  14. Preparation of open porous polycaprolactone microspheres and their applications as effective cell carriers in hydrogel system

    International Nuclear Information System (INIS)

    Common hydrogel, composed of synthetic polymers or natural polysaccharides could not support the adhesion of anchorage-dependent cells due to the lack of cell affinitive interface and high cell constraint. The use of porous polyester microspheres as cell-carriers and introduction of cell-loaded microspheres into the hydrogel system might overcome the problem. However, the preparation of the open porous microsphere especially using polycaprolactone (PCL) has been rarely reported. Here, the open porous PCL microspheres were fabricated via the combined emulsion/solvent evaporation and particle leaching method. The microspheres exhibited porous surface and inter-connective pore structure. Additionally, the pore structure could be easily controlled by adjusting the processing parameters. The surface pore size could be altered from 20 μm to 80 μm and the internal porosities were varied from 30% to 70%. The obtained microspheres were evaluated to delivery mesenchymal stem cells (MSCs) and showed the improved cell adhesion and growth when compared with the non-porous microspheres. Then, the MSCs loaded microspheres were introduced into agarose hydrogel. MSCs remained alive and sustained proliferation in microsphere/agarose composite in 5-day incubation while a decrement of MSCs viabilities was found in agarose hydrogel without microspheres. The results indicated that the microsphere/hydrogel composite had a great potential in cell therapy and injectable system for tissue regeneration. Highlights: ► The open porous polycaprolactone microspheres were fabricated using paraffin as a porogen. ► The microspheres exhibited porous surface and inter-connective pore structure. ► The surface and internal pore size and porosity of microsphere could be controlled. ► The porous microspheres exhibited an improved cell adhesion and proliferation. ► Mesenchymal stem cells survived and proliferated in microsphere/hydrogel composite.

  15. The pyrimidine nucleotide carrier PNC1 and mitochondrial trafficking of thymidine phosphates in cultured human cells

    International Nuclear Information System (INIS)

    In cycling cells cytosolic de novo synthesis of deoxynucleotides is the main source of precursors for mitochondrial (mt) DNA synthesis. The transfer of deoxynucleotides across the inner mt membrane requires protein carriers. PNC1, a SLC25 family member, exchanges pyrimidine nucleoside triphosphates in liposomes and its downregulation decreases mtUTP concentration in cultured cells. By an isotope-flow protocol we confirmed transport of uridine nucleotides by PNC1 in intact cultured cells and investigated PNC1 involvement in the mt trafficking of thymidine phosphates. Key features of our approach were the manipulation of PNC1 expression by RNA interference or inducible overexpression, the employment of cells proficient or deficient for cytosolic thymidine kinase (TK1) to distinguish the direction of flow of thymidine nucleotides across the mt membrane during short pulses with [3H]-thymidine, the determination of mtdTTP specific radioactivity to quantitate the rate of mtdTTP export to the cytoplasm. Downregulation of PNC1 in TK1− cells increased labeled dTTP in mitochondria due to a reduced rate of export. Overexpression of PNC1 in TK1+ cells increased mtdTTP pool size and radioactivity, suggesting an involvement in the import of thymidine phosphates. Thus PNC1 is a component of the network regulating the mtdTTP pool in human cells. -- Highlights: ► Thymidine phosphates exchange between mitochondria and cytosol in mammalian cells. siRNA-downregulation of PNC1 delays mitochondrial dTTP export in TK1− cells. ► PNC1 overexpression accumulates dTTP in mitochondria of TK1+ cells. ► PNC1 exchanges thymidine nucleotides across the mitochondrial inner membrane. ► PNC1 participates in the regulation of the mtdTTP pool supporting mtDNA synthesis.

  16. Quantitative Carrier Density Wave Imaging in Silicon Solar Cells Using Photocarrier Radiometry and Lock-in Carrierography

    Science.gov (United States)

    Sun, Q. M.; Melnikov, A.; Mandelis, A.

    2016-04-01

    InGaAs camera-based low-frequency homodyne and high-frequency heterodyne lock-in carrierographies (LIC) are introduced for spatially resolved imaging of optoelectronic properties of Si solar cells. Based on the full theory of solar cell photocarrier radiometry (PCR), several simplification steps were performed aiming at the open circuit case, and a concise expression of the base minority carrier density depth profile was obtained. The model shows that solar cell PCR/LIC signals are mainly sensitive to the base minority carrier lifetime. Both homodyne and heterodyne frequency response data at selected locations on a mc-Si solar cell were used to extract the local base minority carrier lifetimes by best fitting local experimental data to theory.

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

    International Nuclear Information System (INIS)

    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

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

    International Nuclear Information System (INIS)

    Mercury exposure is known to increase cardiovascular risk but the underlying cellular mechanisms remain undetermined. We analyzed whether chronic exposure to HgCl2 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 HgCl2 (first dose 4.6 mg kg−1, subsequent doses 0.07 mg kg−1 day−1, 30 days) and cultured aortic VSMC stimulated with HgCl2 (0.05–5 μg/ml) were used. Treatment of rats with HgCl2 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 HgCl2: 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 HgCl2. Blockade of ERK1/2 and p38 signaling pathways abolished the HgCl2-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 HgCl2 exposure induces vascular remodeling. ► HgCl2 induces proliferation and decreased cell size in vascular smooth muscle cells. ► HgCl2 induces MAPK activation, oxidative stress and COX-2 expression. ► Inhibition of

  19. 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

  20. Perspectives on the Use of Mesenchymal Stem Cells in Vascularized Composite Allotransplantation

    Directory of Open Access Journals (Sweden)

    Jan A. Plock

    2013-07-01

    Full Text Available Reconstructive transplantation has emerged as clinical reality over the past decade. Utilizing standard immunosuppressive drugs has proven feasible in face and hand transplantation to achieve long-term graft acceptance. As vascularized composite tissue allotransplantation is not a life-saving procedure compared to solid organ transplantation alternative protocols with less long-term side effects are even more desirable. Allograft tolerance is the holy grail of many cell-based concepts and recent data in the field is most promising. Immunomodulation with mesenchymal stem cells from bone marrow and adipose tissue has shown high potential in this respect. This article is aiming at giving an overview on the experimental studies available, the scientific background and clinical applications. Furthermore we address essential questions prior to the use of mesenchymal stem cells in reconstructive allotransplantation.

  1. Urokinase Receptor Mediates Osteogenic Differentiation of Mesenchymal Stem Cells and Vascular Calcification via the Complement C5a Receptor

    OpenAIRE

    Anaraki, Parnian Kalbasi; Patecki, Margret; Larmann, Jan; Tkachuk, Sergey; Jurk, Kerstin; Haller, Hermann; Theilmeier, Gregor; Dumler, Inna

    2013-01-01

    Vascular calcification is a severe consequence of several pathological processes with a lack of effective therapy. Recent studies suggest that circulating and resident mesenchymal stem cells (MSC) contribute to the osteogenic program of vascular calcification. Molecular mechanisms underlying MSC osteogenic potential and differentiation remain, however, sparsely explored. We investigated a role for the complement receptor C5aR in these processes. We found that expression of C5aR was upregulate...

  2. Adiponectin inhibits oxidized low density lipoprotein-induced increase in matrix metalloproteinase 9 expression in vascular smooth muscle cells

    OpenAIRE

    Saneipour, Maryam; Ghatreh-Samani, Keihan; Heydarian, Esfandiar; Farrokhi, Effat; Abdian, Narges

    2015-01-01

    BACKGROUND High expression of matrix metalloproteinase 9 (MMP9) during vascular injury and inflammation plays an important role in atherosclerotic plaque formation and rupture. In the process of atherosclerosis, oxidized low-density lipoprotein (oxLDL) upregulates MMP9 in human aortic vascular smooth muscle cells (HA/VSMCs). Adiponectin is an adipose tissue-derived hormone that has been shown to exert anti-atherogenic and anti-inflammatory effects. The aim of this study was to investigate the...

  3. Differential effects of formoterol on thrombin- and PDGF-induced proliferation of human pulmonary arterial vascular smooth muscle cells

    OpenAIRE

    Goncharova Elena A; Khavin Irene S; Goncharov Dmitry A; Krymskaya Vera P

    2012-01-01

    Abstract Background Increased pulmonary arterial vascular smooth muscle (PAVSM) cell proliferation is a key pathophysiological component of pulmonary vascular remodeling in pulmonary arterial hypertension (PH). The long-acting β2-adrenergic receptor (β2AR) agonist formoterol, a racemate comprised of (R,R)- and (S,S)-enantiomers, is commonly used as a vasodilator in chronic obstructive pulmonary disease (COPD). PH, a common complication of COPD, increases patients’ morbidity and reduces surviv...

  4. Differential effects of formoterol on thrombin- and PDGF-induced proliferation of human pulmonary arterial vascular smooth muscle cells

    OpenAIRE

    Goncharova, Elena A.; Khavin, Irene S; Goncharov, Dmitry A; Vera P Krymskaya

    2012-01-01

    Background Increased pulmonary arterial vascular smooth muscle (PAVSM) cell proliferation is a key pathophysiological component of pulmonary vascular remodeling in pulmonary arterial hypertension (PH). The long-acting β2-adrenergic receptor (β2AR) agonist formoterol, a racemate comprised of (R,R)- and (S,S)-enantiomers, is commonly used as a vasodilator in chronic obstructive pulmonary disease (COPD). PH, a common complication of COPD, increases patients’ morbidity and reduces survival. Recen...

  5. Calphostin-C induction of vascular smooth muscle cell apoptosis proceeds through phospholipase D and microtubule inhibition.

    Science.gov (United States)

    Zheng, Xi-Long; Gui, Yu; Du, Guangwei; Frohman, Michael A; Peng, Dao-Quan

    2004-02-20

    Calphostin-C, a protein kinase C inhibitor, induces apoptosis of cultured vascular smooth muscle cells. However, the mechanisms are not completely defined. Because apoptosis of vascular smooth muscle cells is critical in several proliferating vascular diseases such as atherosclerosis and restenosis after angioplasty, we decided to investigate the mechanisms underlying the calphostin-C-induced apoptotic pathway. We show here that apoptosis is inhibited by the addition of exogenous phosphatidic acid, a metabolite of phospholipase D (PLD), and that calphostin-C inhibits completely the activities of both isoforms of PLD, PLD1 and PLD2. Overexpression of either PLD1 or PLD2 prevented the vascular smooth muscle cell apoptosis induced by serum withdrawal but not the calphostin-C-elicited apoptosis. These data suggest that PLDs have anti-apoptotic effects and that complete inhibition of PLD activity by calphostin-C induces smooth muscle cell apoptosis. We also report that calphostin-C induced microtubule disruption and that the addition of exogenous phosphatidic acid inhibits calphostin-C effects on microtubules, suggesting a role for PLD in stabilizing the microtubule network. Overexpressing PLD2 in Chinese hamster ovary cells phenocopies this result, providing strong support for the hypothesis. Finally, taxol, a microtubule stabilizer, not only inhibited the calphostin-C-induced microtubule disruption but also inhibited apoptosis. We therefore conclude that calphostin-C induces apoptosis of cultured vascular smooth muscle cells through inhibiting PLD activity and subsequent microtubule polymerization. PMID:14660552

  6. Unique cell type-specific junctional complexes in vascular endothelium of human and rat liver sinusoids.

    Directory of Open Access Journals (Sweden)

    Cyrill Géraud

    Full Text Available Liver sinusoidal endothelium is strategically positioned to control access of fluids, macromolecules and cells to the liver parenchyma and to serve clearance functions upstream of the hepatocytes. While clearance of macromolecular debris from the peripheral blood is performed by liver sinusoidal endothelial cells (LSECs using a delicate endocytic receptor system featuring stabilin-1 and -2, the mannose receptor and CD32b, vascular permeability and cell trafficking are controlled by transcellular pores, i.e. the fenestrae, and by intercellular junctional complexes. In contrast to blood vascular and lymphatic endothelial cells in other organs, the junctional complexes of LSECs have not yet been consistently characterized in molecular terms. In a comprehensive analysis, we here show that LSECs express the typical proteins found in endothelial adherens junctions (AJ, i.e. VE-cadherin as well as α-, β-, p120-catenin and plakoglobin. Tight junction (TJ transmembrane proteins typical of endothelial cells, i.e. claudin-5 and occludin, were not expressed by rat LSECs while heterogenous immunreactivity for claudin-5 was detected in human LSECs. In contrast, junctional molecules preferentially associating with TJ such as JAM-A, B and C and zonula occludens proteins ZO-1 and ZO-2 were readily detected in LSECs. Remarkably, among the JAMs JAM-C was considerably over-expressed in LSECs as compared to lung microvascular endothelial cells. In conclusion, we show here that LSECs form a special kind of mixed-type intercellular junctions characterized by co-occurrence of endothelial AJ proteins, and of ZO-1 and -2, and JAMs. The distinct molecular architecture of the intercellular junctional complexes of LSECs corroborates previous ultrastructural findings and provides the molecular basis for further analyses of the endothelial barrier function of liver sinusoids under pathologic conditions ranging from hepatic inflammation to formation of liver metastasis.

  7. Protocatechuic aldehyde inhibits migration and proliferation of vascular smooth muscle cells and intravascular thrombosis

    International Nuclear Information System (INIS)

    Highlights: ► Protocatechuic aldehyde (PCA) inhibits ROS production in VSMCs. ► PCA inhibits proliferation and migration in PDGF-induced VSMCs. ► PCA has anti-platelet effects in ex vivo rat whole blood. ► We report the potential therapeutic role of PCA in atherosclerosis. -- Abstract: The migration and proliferation of vascular smooth muscle cells (VSMCs) and formation of intravascular thrombosis play crucial roles in the development of atherosclerotic lesions. This study examined the effects of protocatechuic aldehyde (PCA), a compound isolated from the aqueous extract of the root of Salvia miltiorrhiza, an herb used in traditional Chinese medicine to treat a variety of vascular diseases, on the migration and proliferation of VSMCs and platelets due to platelet-derived growth factor (PDGF). DNA 5-bromo-2′-deoxy-uridine (BrdU) incorporation and wound-healing assays indicated that PCA significantly attenuated PDGF-induced proliferation and migration of VSMCs at a pharmacologically relevant concentration (100 μM). On a molecular level, we observed down-regulation of the phosphatidylinositol 3-kinase (PI3K)/Akt and the mitogen-activated protein kinase (MAPK) pathways, both of which regulate key enzymes associated with migration and proliferation. We also found that PCA induced S-phase arrest of the VSMC cell cycle and suppressed cyclin D2 expression. In addition, PCA inhibited PDGF-BB-stimulated reactive oxygen species production in VSMCs, indicating that PCA’s antioxidant properties may contribute to its suppression of PDGF-induced migration and proliferation in VSMCs. Finally, PCA exhibited an anti-thrombotic effect related to its inhibition of platelet aggregation, confirmed with an aggregometer. Together, these findings suggest a potential therapeutic role of PCA in the treatment of atherosclerosis and angioplasty-induced vascular restenosis.

  8. Protocatechuic aldehyde inhibits migration and proliferation of vascular smooth muscle cells and intravascular thrombosis

    Energy Technology Data Exchange (ETDEWEB)

    Moon, Chang Yoon [The Hotchkiss School, Lakeville, CT (United States); Endocrinology, Brain Korea 21 Project for Medical Science, Institute of Endocrine Research, and Severance Integrative Research Institute for Cerebral and Cardiovascular Disease, Yonsei University College of Medicine, Seoul (Korea, Republic of); Ku, Cheol Ryong [Endocrinology, Brain Korea 21 Project for Medical Science, Institute of Endocrine Research, and Severance Integrative Research Institute for Cerebral and Cardiovascular Disease, Yonsei University College of Medicine, Seoul (Korea, Republic of); Cho, Yoon Hee, E-mail: wooriminji@gmail.com [Endocrinology, Brain Korea 21 Project for Medical Science, Institute of Endocrine Research, and Severance Integrative Research Institute for Cerebral and Cardiovascular Disease, Yonsei University College of Medicine, Seoul (Korea, Republic of); Lee, Eun Jig, E-mail: ejlee423@yuhs.ac [Endocrinology, Brain Korea 21 Project for Medical Science, Institute of Endocrine Research, and Severance Integrative Research Institute for Cerebral and Cardiovascular Disease, Yonsei University College of Medicine, Seoul (Korea, Republic of); Endocrinology, Northwestern University Feinberg School of Medicine, Chicago, IL (United States)

    2012-06-22

    Highlights: Black-Right-Pointing-Pointer Protocatechuic aldehyde (PCA) inhibits ROS production in VSMCs. Black-Right-Pointing-Pointer PCA inhibits proliferation and migration in PDGF-induced VSMCs. Black-Right-Pointing-Pointer PCA has anti-platelet effects in ex vivo rat whole blood. Black-Right-Pointing-Pointer We report the potential therapeutic role of PCA in atherosclerosis. -- Abstract: The migration and proliferation of vascular smooth muscle cells (VSMCs) and formation of intravascular thrombosis play crucial roles in the development of atherosclerotic lesions. This study examined the effects of protocatechuic aldehyde (PCA), a compound isolated from the aqueous extract of the root of Salvia miltiorrhiza, an herb used in traditional Chinese medicine to treat a variety of vascular diseases, on the migration and proliferation of VSMCs and platelets due to platelet-derived growth factor (PDGF). DNA 5-bromo-2 Prime -deoxy-uridine (BrdU) incorporation and wound-healing assays indicated that PCA significantly attenuated PDGF-induced proliferation and migration of VSMCs at a pharmacologically relevant concentration (100 {mu}M). On a molecular level, we observed down-regulation of the phosphatidylinositol 3-kinase (PI3K)/Akt and the mitogen-activated protein kinase (MAPK) pathways, both of which regulate key enzymes associated with migration and proliferation. We also found that PCA induced S-phase arrest of the VSMC cell cycle and suppressed cyclin D2 expression. In addition, PCA inhibited PDGF-BB-stimulated reactive oxygen species production in VSMCs, indicating that PCA's antioxidant properties may contribute to its suppression of PDGF-induced migration and proliferation in VSMCs. Finally, PCA exhibited an anti-thrombotic effect related to its inhibition of platelet aggregation, confirmed with an aggregometer. Together, these findings suggest a potential therapeutic role of PCA in the treatment of atherosclerosis and angioplasty-induced vascular restenosis.

  9. SM22α inhibits vascular inflammation via stabilization of IκBα in vascular smooth muscle cells.

    Science.gov (United States)

    Shu, Ya-Nan; Zhang, Fan; Bi, Wei; Dong, Li-Hua; Zhang, Dan-Dan; Chen, Rong; Lv, Pin; Xie, Xiao-Li; Lin, Yan-Ling; Xue, Zhen-Ying; Li, Haibo; Miao, Sui-Bing; Zhao, Li-Li; Wang, Hong; Han, Mei

    2015-07-01

    Smooth muscle (SM) 22α, an actin-binding protein, is down-regulated in atherosclerotic arteries. Disruption of SM22α promotes arterial inflammation through activation of reactive oxygen species (ROS)-mediated nuclear factor (NF)-κB pathways. This study aimed to investigate the mechanisms by which SM22α regulates vascular inflammatory response. The ligation injury model of SM22α(-/-) mice displayed up-regulation of inflammatory molecules MCP-1, VCAM-1, and ICAM-1 in the carotid arteries. Similar results were discovered in human atherosclerotic samples. In vitro studies, overexpression of SM22α attenuated TNF-α-induced IκBα phosphorylation and degradation, accompanied by decreased NF-κB activity and reduced inflammatory molecule expression. Using coimmunoprecipitation, we found that SM22α interacted with and stabilized IκBα in quiescent VSMCs. Upon TNF-α stimulation, SM22α was phosphorylated by casein kinase (CK) II at Thr139, leading to dissociation of SM22α from IκBα, followed by IκBα degradation and NF-κB activation. Our findings demonstrate that SM22α is a phosphorylation-regulated suppressor of IKK-IκBα-NF-κB signaling cascades. SM22α may be a novel therapeutic target for human vascular diseases and other inflammatory conditions. PMID:25937534

  10. Time-resolved, nonequilibrium carrier dynamics in Si-on-glass thin films for photovoltaic cells

    International Nuclear Information System (INIS)

    A femtosecond pump–probe spectroscopy method was used to characterize the growth process and transport properties of amorphous silicon-on-glass, thin films, intended as absorbers for photovoltaic cells. We collected normalized transmissivity change (ΔT/T) waveforms and interpreted them using a comprehensive three-rate equation electron trapping and recombination model. Optically excited ∼300–500 nm thick Si films exhibited a bi-exponential carrier relaxation with the characteristic times varying from picoseconds to nanoseconds depending on the film growth process. From our comprehensive trapping model, we could determine that for doped and intrinsic films with very low hydrogen dilution the dominant relaxation mode was carrier trapping; while for intrinsic films with large hydrogen content and some texture, it was the standard electron–phonon cooling. In both cases, the initial nonequilibrium relaxation was followed by Shockley–Read–Hall recombination. An excellent fit between the model and the ΔT/T experimental transients was obtained and a correlation between the Si film growth process, its hydrogen content, and the associated trap concentration was demonstrated. (paper)

  11. Interfacial Study To Suppress Charge Carrier Recombination for High Efficiency Perovskite Solar Cells.

    Science.gov (United States)

    Adhikari, Nirmal; Dubey, Ashish; Khatiwada, Devendra; Mitul, Abu Farzan; Wang, Qi; Venkatesan, Swaminathan; Iefanova, Anastasiia; Zai, Jiantao; Qian, Xuefeng; Kumar, Mukesh; Qiao, Qiquan

    2015-12-01

    We report effects of an interface between TiO2-perovskite and grain-grain boundaries of perovskite films prepared by single step and sequential deposited technique using different annealing times at optimum temperature. Nanoscale kelvin probe force microscopy (KPFM) measurement shows that charge transport in a perovskite solar cell critically depends upon the annealing conditions. The KPFM results of single step and sequential deposited films show that the increase in potential barrier suppresses the back-recombination between electrons in TiO2 and holes in perovskite. Spatial mapping of the surface potential within perovskite film exhibits higher positive potential at grain boundaries compared to the surface of the grains. The average grain boundary potential of 300-400 mV is obtained upon annealing for sequentially deposited films. X-ray diffraction (XRD) spectra indicate the formation of a PbI2 phase upon annealing which suppresses the recombination. Transient analysis exhibits that the optimum device has higher carrier lifetime and short carrier transport time among all devices. An optimum grain boundary potential and proper band alignment between the TiO2 electron transport layer (ETL) and the perovskite absorber layer help to increase the overall device performance. PMID:26579732

  12. Time-resolved, nonequilibrium carrier dynamics in Si-on-glass thin films for photovoltaic cells

    Science.gov (United States)

    Serafini, John; Akbas, Yunus; Crandall, Lucas; Bellman, Robert; Kosik Williams, Carlo; Sobolewski, Roman

    2016-04-01

    A femtosecond pump-probe spectroscopy method was used to characterize the growth process and transport properties of amorphous silicon-on-glass, thin films, intended as absorbers for photovoltaic cells. We collected normalized transmissivity change (ΔT/T) waveforms and interpreted them using a comprehensive three-rate equation electron trapping and recombination model. Optically excited ˜300-500 nm thick Si films exhibited a bi-exponential carrier relaxation with the characteristic times varying from picoseconds to nanoseconds depending on the film growth process. From our comprehensive trapping model, we could determine that for doped and intrinsic films with very low hydrogen dilution the dominant relaxation mode was carrier trapping; while for intrinsic films with large hydrogen content and some texture, it was the standard electron-phonon cooling. In both cases, the initial nonequilibrium relaxation was followed by Shockley-Read-Hall recombination. An excellent fit between the model and the ΔT/T experimental transients was obtained and a correlation between the Si film growth process, its hydrogen content, and the associated trap concentration was demonstrated.

  13. Photo-generated carriers lose energy during extraction from polymer-fullerene solar cells

    KAUST Repository

    Melianas, Armantas

    2015-11-05

    In photovoltaic devices, the photo-generated charge carriers are typically assumed to be in thermal equilibrium with the lattice. In conventional materials, this assumption is experimentally justified as carrier thermalization completes before any significant carrier transport has occurred. Here, we demonstrate by unifying time-resolved optical and electrical experiments and Monte Carlo simulations over an exceptionally wide dynamic range that in the case of organic photovoltaic devices, this assumption is invalid. As the photo-generated carriers are transported to the electrodes, a substantial amount of their energy is lost by continuous thermalization in the disorder broadened density of states. Since thermalization occurs downward in energy, carrier motion is boosted by this process, leading to a time-dependent carrier mobility as confirmed by direct experiments. We identify the time and distance scales relevant for carrier extraction and show that the photo-generated carriers are extracted from the operating device before reaching thermal equilibrium.

  14. Visualization of Photoexcited Carrier Responses in a Solar Cell Using Optical Pump—Terahertz Emission Probe Technique

    Science.gov (United States)

    Nakanishi, Hidetoshi; Ito, Akira; Takayama, Kazuhisa; Kawayama, Iwao; Murakami, Hironaru; Tonouchi, Masayoshi

    2016-05-01

    We observed photoexcited carrier responses in solar cells excited by femtosecond laser pulses with spatial and temporal resolution using an optical pump-terahertz emission probe technique. We visualized the ultrafast local variation of the intensity of terahertz emission from a polycrystalline silicon solar cell using this technique and clearly observed the change in signals between a grain boundary and the inside of a grain in the solar cell. Further, the time evolution of the pump-probe signals of the polycrystalline and monocrystalline silicon solar cells was observed, and the relaxation times of photoexcited carriers in the emitter layers of crystalline silicon solar cells were estimated using this technique. The estimated relaxation time was consistent with the lifetime of the Auger recombination process that was dominant in heavily doped silicon used as an emitter layer for the silicon solar cells, which is difficult to obtain with photoluminescence method commonly used for the evaluation of solar cells.

  15. 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.

  16. Human vascular endothelial cells transport foreign exosomes from cow's milk by endocytosis.

    Science.gov (United States)

    Kusuma, Rio Jati; Manca, Sonia; Friemel, Taylor; Sukreet, Sonal; Nguyen, Christopher; Zempleni, Janos

    2016-05-15

    Encapsulation of microRNAs in exosomes confers protection against degradation and a vehicle for shuttling of microRNAs between cells and tissues, and cellular uptake by endocytosis. Exosomes can be found in foods including milk. Humans absorb cow's milk exosomes and deliver the microRNA cargo to peripheral tissues, consistent with gene regulation by dietary nucleic acids across species boundaries. Here, we tested the hypothesis that human vascular endothelial cells transport milk exosomes by endocytosis, constituting a step crucial for the delivery of dietary exosomes and their cargo to peripheral tissues. We tested this hypothesis by using human umbilical vein endothelial cells and fluorophore-labeled exosomes isolated from cow's milk. Exosome uptake followed Michaelis-Menten kinetics (Vmax = 0.057 ± 0.004 ng exosome protein × 40,000 cells/h; Km = 17.97 ± 3.84 μg exosomal protein/200 μl media) and decreased by 80% when the incubation temperature was lowered from 37°C to 4°C. When exosome surface proteins were removed by treatment with proteinase K, or transport was measured in the presence of the carbohydrate competitor d-galactose or measured in the presence of excess unlabeled exosomes, transport rates decreased by 45% to 80% compared with controls. Treatment with an inhibitor of endocytosis, cytochalasin D, caused a 50% decrease in transport. When fluorophore-labeled exosomes were administered retro-orbitally, exosomes accumulated in liver, spleen, and lungs in mice. We conclude that human vascular endothelial cells transport bovine exosomes by endocytosis and propose that this is an important step in the delivery of dietary exosomes and their cargo to peripheral tissues. PMID:26984735

  17. Effect of Oxysterol-Induced Apoptosis of Vascular Smooth Muscle Cells on Experimental Hypercholesterolemia

    Directory of Open Access Journals (Sweden)

    Sonia Perales

    2009-01-01

    Full Text Available Smooth muscle cells (SMCs undergo changes related to proliferation and apoptosis in the physiological remodeling of vessels and in diseases such as atherosclerosis and restenosis. Recent studies also have demonstrated the vascular cell proliferation and programmed cell death contribute to changes in vascular architecture in normal development and in disease. The present study was designed to investigate the apoptotic pathways induced by 25-hydroxycholesterol in SMCs cultures, using an in vivo/in vitro cell model in which SMCs were isolated and culture from chicken exposed to an atherogenic cholesterol-rich diet (SMC-Ch and/or an antiatherogenic fish oil-rich diet (SMC-Ch-FO. Cells were exposed in vitro to 25-hydroxycholesterol to study levels of apoptosis and apoptotic proteins Bcl-2, Bcl-XL and Bax and the expression of bcl-2 and bcl-xL, genes. The quantitative real-time reverse transcriptase-polymerase chain reaction and the Immunoblotting western blot analysis showed that 25-hydroxycholesterol produces apoptosis in SMCs, mediated by a high increase in Bax protein and Bax gene expression. These changes were more marked in SMC-Ch than in SMC-Ch-FO, indicating that dietary cholesterol produces changes in SMCs that make them more susceptible to 25-hydroxycholesterol-mediated apoptosis. Our results suggest that the replacement of a cholesterol-rich diet with a fish oil-rich diet produces some reversal of cholesterol-induced changes in the apoptotic pathways induced by 25-hydroxycholesterol in SMCs cultures, making SMCs more resistant to apoptosis.

  18. Effect of oxysterol-induced apoptosis of vascular smooth muscle cells on experimental hypercholesterolemia.

    Science.gov (United States)

    Perales, Sonia; Alejandre, M José; Palomino-Morales, Rogelio; Torres, Carolina; Iglesias, Jose; Linares, Ana

    2009-01-01

    Smooth muscle cells (SMCs) undergo changes related to proliferation and apoptosis in the physiological remodeling of vessels and in diseases such as atherosclerosis and restenosis. Recent studies also have demonstrated the vascular cell proliferation and programmed cell death contribute to changes in vascular architecture in normal development and in disease. The present study was designed to investigate the apoptotic pathways induced by 25-hydroxycholesterol in SMCs cultures, using an in vivo/in vitro cell model in which SMCs were isolated and culture from chicken exposed to an atherogenic cholesterol-rich diet (SMC-Ch) and/or an antiatherogenic fish oil-rich diet (SMC-Ch-FO). Cells were exposed in vitro to 25-hydroxycholesterol to study levels of apoptosis and apoptotic proteins Bcl-2, Bcl-X(L) and Bax and the expression of bcl-2 and bcl-x(L), genes. The quantitative real-time reverse transcriptase-polymerase chain reaction and the Immunoblotting western blot analysis showed that 25-hydroxycholesterol produces apoptosis in SMCs, mediated by a high increase in Bax protein and Bax gene expression. These changes were more marked in SMC-Ch than in SMC-Ch-FO, indicating that dietary cholesterol produces changes in SMCs that make them more susceptible to 25-hydroxycholesterol-mediated apoptosis. Our results suggest that the replacement of a cholesterol-rich diet with a fish oil-rich diet produces some reversal of cholesterol-induced changes in the apoptotic pathways induced by 25-hydroxycholesterol in SMCs cultures, making SMCs more resistant to apoptosis. PMID:19727411

  19. Inhibitive effects of anti-oxidative vitamins on mannitol-induced apoptosis of vascular endothelial cells

    Institute of Scientific and Technical Information of China (English)

    PAN Kai-yu; SHEN Mei-ping; YE Zhi-hong; DAI Xiao-na; SHANG Shi-qiang

    2006-01-01

    Objective: Study blood vessel injury and gene expression indicating vascular endothelial cell apoptosis induced by mannitol with and without administration of anti-oxidative vitamins. Methods: Healthy rabbits were randomly divided into four groups. Mannitol was injected into the vein of the rabbit ear in each animal. Pre-treatment prior to mannitol injection was performed with normal saline (group B), vitamin C (group C) and vitamin E (group D). Blood vessel injury was assessed under electron and light microscopy. In a second experiment, cell culture specimen of human umbilical vein endothelial cells were treated with mannitol. Pre-treatment was done with normal saline (sample B), vitamin C (sample C) and vitamin E (sample D).Total RNA was extracted with the original single step procedure, followed by hybridisation and analysis of gene expression.Results: In the animal experiment, serious blood vessel injury was seen in group A and group B. Group D showed light injury only,and normal tissue without pathological changes was seen in group C. Of all 330 apoptosis-related genes analysed in human cell culture specimen, no significant difference was seen after pre-treatment with normal saline, compared with the gene chip without pre-treatment. On the gene chip pre-treated with vitamin C, 45 apoptosis genes were down-regulated and 34 anti-apoptosis genes were up-regulated. Pre-treatment with vitamin E resulted in the down-regulation of 3 apoptosis genes. Conclusion: Vitamin C can protect vascular endothelial cells from mannitol-induced injury.

  20. Ouabain at pathological concentrations might induce damage in human vascular endothelial cells

    Institute of Scientific and Technical Information of China (English)

    Yan-ping REN; Ruo-wen HUANG; Zhuo-ren L(U)

    2006-01-01

    Aim: To examine the time- and dose-dependent effects of ouabain on human umbilical vein endothelial cells (HUVEC) in vivo, and the changes in aortic endothelium and the different expression levels of Kv4.2 in vitro. Methods: The proliferation of HUVEC and cell death were determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay, the incorporation of [3H]TdR,trypan blue staining, and lactate dehydrogenase (LDH) release. The response of endothelial cells to ouabain was explored with a complementary DNA microarray and a candidate gene was found. "Ouabain-sensitive" hypertensive rats were established by chronic administration of ouabain. Changes in the aortic endothelium were observed by electron microscopy, and the expression level of Ky4.2 in different animals was studied by using real-time quantitative reverse transcription-polymerase chain reaction (RT-PCR). Results: Ouabain stimulated the proliferation of HUVEC at physiological concentrations (0.3-0.9 nmol/L). Ouabain at pathological concentrations (0.9-1.8 nmol/L) inhibited proliferation and induced cell death, mRNA profile analysis indicated that 340 genes were differentially expressed after ouabain treatment: 145 were upregulated, of which 6 were upregulated significantly, including KCND2 (encoding the potassium voltagegated channel shal-related subfamily member 2). The upregulated genes were mainly related to cell metabolism and transcription. In ouabain-sensitive hypertensive rats, the aortic endothelium was damaged and Kv4.2 (coded by KCND2)was over-expressed. Conclusion: The physiological role of ouabain in HUVEC might involve the control of growth and metabolism. Ouabain at pathological concentrations might affect the structure and function of the vascular endothelium by modification of expression of the KCND2 gene, and participate vascular remodeling in hypertension.

  1. Tunnel oxide passivated rear contact for large area n-type front junction silicon solar cells providing excellent carrier selectivity

    Directory of Open Access Journals (Sweden)

    Yuguo Tao

    2016-01-01

    Full Text Available Carrier-selective contact with low minority carrier recombination and efficient majority carrier transport is mandatory to eliminate metal-induced recombination for higher energy conversion efficiency for silicon (Si solar cells. In the present study, the carrier-selective contact consists of an ultra-thin tunnel oxide and a phosphorus-doped polycrystalline Si (poly-Si thin film formed by plasma enhanced chemical vapor deposition (PECVD and subsequent thermal crystallization. It is shown that the poly-Si film properties (doping level, crystallization and dopant activation anneal temperature are crucial for achieving excellent contact passivation quality. It is also demonstrated quantitatively that the tunnel oxide plays a critical role in this tunnel oxide passivated contact (TOPCON scheme to realize desired carrier selectivity. Presence of tunnel oxide increases the implied Voc (iVoc by ~ 125 mV. The iVoc value as high as 728 mV is achieved on symmetric structure with TOPCON on both sides. Large area (239 cm2 n-type Czochralski (Cz Si solar cells are fabricated with homogeneous implanted boron emitter and screen-printed contact on the front and TOPCON on the back, achieving 21.2% cell efficiency. Detailed analysis shows that the performance of these cells is mainly limited by boron emitter recombination on the front side.

  2. The construction of an in vitro three-dimensional hematopoietic microenvironment for mouse bone marrow cells employing porous carriers.

    Science.gov (United States)

    Tomimori, Y; Takagi, M; Yoshida, T

    2000-10-01

    Spatial development of mouse bone marrow cellsemploying porous carriers was investigated in order todesign a bioreactor with a three-dimensionalhematopoietic microenvironment. Three types of porouscarriers were used for examining the spatialdevelopment of anchorage-dependent primary stromalcells as feeder cells. Stromal cells were found tospread well at a high density on a polyester nonwovendisc carrier (Fibra cel (FC)) under a scanningelectron microscope, while cells on porous cellulosebeads (Microcube (MC), 500 mum pore diameter)spread at a low density; cells on another type ofcellulose porous beads (CPB, 100 mum pore diameter)were globular. Mouse bone marrow cells wereinoculated to dishes containing three types of porouscarriers which shared more than 30% of the bottomsurface in a dish. The concentration of stromal cellsin the well containing FC was lower than that on theother two carriers. However, the weekly output oftotal hematopoietic cell (suspension cells) increasedbetween day 21 and 28 in the culture using FC while itdecreased monotonously in the cultures by use of theother two carriers. The proportion of progenitorcells (BFU-E, CFU-GM) in the total hematopoietic cellpopulation, after showing an initial decrease,increased after 1 week in the culture using FC whilethe proportion decreased monotonously to zero in thecultures using MC and CPB. PMID:19003386

  3. Disturbance of copper homeostasis is a mechanism for homocysteine-induced vascular endothelial cell injury.

    Directory of Open Access Journals (Sweden)

    Daoyin Dong

    Full Text Available Elevation of serum homocysteine (Hcy levels is a risk factor for cardiovascular diseases. Previous studies suggested that Hcy interferes with copper (Cu metabolism in vascular endothelial cells. The present study was undertaken to test the hypothesis that Hcy-induced disturbance of Cu homeostasis leads to endothelial cell injury. Exposure of human umbilical vein endothelial cells (HUVECs to concentrations of Hcy at 0.01, 0.1 or 1 mM resulted in a concentration-dependent decrease in cell viability and an increase in necrotic cell death. Pretreatment of the cells with a final concentration of 5 µM Cu in cultures prevented the effects of Hcy. Hcy decreased intracellular Cu concentrations. HPLC-ICP-MS analysis revealed that Hcy caused alterations in the distribution of intracellular Cu; more Cu was redistributed to low molecular weight fractions. ESI-Q-TOF detected the formation of Cu-Hcy complexes. Hcy also decreased the protein levels of Cu chaperone COX17, which was accompanied by a decrease in the activity of cytochrome c oxidase (CCO and a collapse of mitochondrial membrane potential. These effects of Hcy were all preventable by Cu pretreatment. The study thus demonstrated that Hcy disturbs Cu homeostasis and limits the availability of Cu to critical molecules such as COX17 and CCO, leading to mitochondrial dysfunction and endothelial cell injury.

  4. Disturbance of Copper Homeostasis Is a Mechanism for Homocysteine-Induced Vascular Endothelial Cell Injury

    Science.gov (United States)

    Dong, Daoyin; Wang, Biao; Yin, Wen; Ding, Xueqing; Yu, Jingjing; Kang, Y. James

    2013-01-01

    Elevation of serum homocysteine (Hcy) levels is a risk factor for cardiovascular diseases. Previous studies suggested that Hcy interferes with copper (Cu) metabolism in vascular endothelial cells. The present study was undertaken to test the hypothesis that Hcy-induced disturbance of Cu homeostasis leads to endothelial cell injury. Exposure of human umbilical vein endothelial cells (HUVECs) to concentrations of Hcy at 0.01, 0.1 or 1 mM resulted in a concentration-dependent decrease in cell viability and an increase in necrotic cell death. Pretreatment of the cells with a final concentration of 5 µM Cu in cultures prevented the effects of Hcy. Hcy decreased intracellular Cu concentrations. HPLC-ICP-MS analysis revealed that Hcy caused alterations in the distribution of intracellular Cu; more Cu was redistributed to low molecular weight fractions. ESI-Q-TOF detected the formation of Cu-Hcy complexes. Hcy also decreased the protein levels of Cu chaperone COX17, which was accompanied by a decrease in the activity of cytochrome c oxidase (CCO) and a collapse of mitochondrial membrane potential. These effects of Hcy were all preventable by Cu pretreatment. The study thus demonstrated that Hcy disturbs Cu homeostasis and limits the availability of Cu to critical molecules such as COX17 and CCO, leading to mitochondrial dysfunction and endothelial cell injury. PMID:24204604

  5. Cytotoxicity of some oxysterols on human vascular smooth muscle cells was mediated by apoptosis.

    Science.gov (United States)

    Miyashita, Y; Shirai, K; Ito, Y; Watanabe, J; Urano, Y; Murano, T; Tomioka, H

    1997-01-01

    A decrease in smooth muscle cells is observed in advanced atherosclerotic lesion. To understand this mechanism, we selected oxysterols as candidates for toxic lipid, and examined their cytotoxicity on human cultured vascular smooth muscle cells, together with the manner of cell death. In the presence of 7-ketocholesterol or 7 beta-hydroxycholesterol (50 mumol/L), the percentage of detached cells increased significantly with dose dependency, and an increase in detached cell number and DNA nick detected by terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling study (TUNEL) preceded an increase in lactate dehydrogenase released into the medium. DNA extracted from smooth muscle cells incubated with 7-ketocholesterol or 7 beta-hydroxycholesterol showed a laddering pattern on agarose electrophoresis. In the presence of 7-ketocholesterol or 7 beta-hydroxycholesterol, fragmented DNA quantified by the quantitative sandwich enzyme immunoassay was significantly increased. From these results, it is proposed that 7-ketocholesterol and 7 beta-hydroxycholesterol are toxic to smooth muscle cells, and that this cytotoxicity is mediated by apoptosis. PMID:9638517

  6. Vascular Endothelial Growth Factor A Regulates the Secretion of Different Angiogenic Factors in Lung Cancer Cells.

    Science.gov (United States)

    Frezzetti, Daniela; Gallo, Marianna; Roma, Cristin; D'Alessio, Amelia; Maiello, Monica R; Bevilacqua, Simona; Normanno, Nicola; De Luca, Antonella

    2016-07-01

    Vascular endothelial growth factor A (VEGFA) is one of the main mediators of angiogenesis in non-small cell lung cancer (NSCLC). Recently, it has been described an autocrine feed-forward loop in NSCLC cells in which tumor-derived VEGFA promoted the secretion of VEGFA itself, amplifying the proangiogenic signal. In order to investigate the role of VEGFA in lung cancer progression, we assessed the effects of recombinant VEGFA on proliferation, migration, and secretion of other angiogenic factors in A549, H1975, and HCC827 NSCLC cell lines. We found that VEGFA did not affect NSCLC cell proliferation and migration. On the other hand, we demonstrated that VEGFA not only produced a strong and persistent increase of VEGFA itself but also significantly induced the secretion of a variety of angiogenic factors, including follistatin (FST), hepatocyte growth factor (HGF), angiopoietin-2 (ANGPT2), granulocyte-colony stimulating factor (G-CSF), interleukin (IL)-8, leptin (LEP), platelet/endothelial cell adhesion molecule 1 (PECAM-1), and platelet-derived growth factor bb (PDGF-BB). PI3K/AKT, RAS/ERK, and STAT3 signalling pathways were found to mediate the effects of VEGFA in NSCLC cell lines. We also observed that VEGFA regulation mainly occurred at post-transcriptional level and that NSCLC cells expressed different isoforms of VEGFA. Collectively, our data suggested that VEGFA contributes to lung cancer progression by inducing a network of angiogenic factors, which might offer potential for therapeutic intervention. PMID:26542886

  7. Bone marrow mesenchymal stem cell aggregate: an optimal cell therapy for full-layer cutaneous wound vascularization and regeneration

    Science.gov (United States)

    An, Yulin; wei, Wei; Jing, Huan; Ming, Leiguo; Liu, Shiyu; Jin, Yan

    2015-01-01

    Cutaneous wounds are among the most common soft tissue injuries. Wounds involving dermis suffer more from outside influence and higher risk of chronic inflammation. Therefore the appearance and function restoration has become an imperative in tissue engineering research. In this study, cell-aggregates constructed with green fluorescent protein-expressing (GFP+) rat bone marrow mesenchymal stem cells (BMMSCs) were applied to rat acute full-layer cutaneous wound model to confirm its pro-regeneration ability and compare its regenerative efficacy with the currently thriving subcutaneous and intravenous stem cell administration strategy, with a view to sensing the advantages, disadvantages and the mechanism behind. According to results, cell-aggregates cultured in vitro enjoyed higher expression of several pro-healing genes than adherent cultured cells. Animal experiments showed better vascularization along with more regular dermal collagen deposition for cell-aggregate transplanted models. Immunofluorescence staining on inflammatory cells indicated a shorter inflammatory phase for cell-aggregate group, which was backed up by further RT-PCR. The in situ immunofluorescence staining manifested a higher GFP+-cell engraftment for cell-aggregate transplanted models versus cell administered ones. Thus it is safe to say the BMMSCs aggregate could bring superior cutaneous regeneration for full layer cutaneous wound to BMMSCs administration, both intravenous and subcutaneous. PMID:26594024

  8. THE STATE OF CELL MEDIATED IMMUNITY AMONG HEPATITIS B SURFACE ,ANTGENI CARRIERS IN IRAN,

    Directory of Open Access Journals (Sweden)

    A. MASSOUD

    1987-06-01

    Full Text Available Cell-mediated immune (CMI s t a t us and sub- popul at i ons o f pe r ipheral b l ood lymphocytes were investigated in one hundre d volunt a ry blood donors who were car r ier s of Ag • HE S A signi f i c ant decr e ase of t otal T-cells observed in HB Ag carri e rs as compared t o normal controls. The percenS t age o f active T-cells a nd B-lymphocytes did not d i f f e r signi f icant ly between the t wo groups ."nAddi t ion of aut ologous serum from HE Ag c a r r iers t o s t heir l ymphocyt e s reduced the numbe r of detectabl e cells in HE Ag carriers . This reduction coul d be due to the s presence of a r osette i nhi bitory f actor in their serum. Our studies demonstrated a failur e o f CMI among HB Ags car r i ers detected by the l e ukocyte migr ation i nhibition (LMI test. This failure cannot be attributed to the presence of HE Ag-AB complexes in their serum. It is s possible that specific failure of CMI allows the hepatitis B virus to remain harmless in carriers a Hepatitis B surface-antigen (HE Ag; Hepatitis Bs coreantigen (HE Ag and Hepatitis Be-antigen (HE Ag, c e have been established as indicating ineffectivity in viral hepatitis B ({I, 6 , 20, 28."nA number of infected individuals also developed clini cal evidence of disease and HE Ag may s the serum of some subjects for a long rema•ln present I•n time (18. It has been suggested that to a defect in CMI, the persistence of HB Ag s whether liver disease is is related present or not, and impairment of the lymphocyte response to phytohaemagglutinin (PHA in this group is presented in evide•"nnee (8, •9 , 13, 24, 25 .In contrast, other workers report a normal respons e t o PHA in healthy carriers of HE Ag and s they concludE that the defective T-cell response is relat ed to the live!' disease rather than the immune system (31. Dudley et al (8 have suggested that liver damage occurring after hepatitis B infection, may be an effect of thymus-dependent lymphocytes (12."n

  9. Production of Experimental Malignant Pleural Effusions Is Dependent on Invasion of the Pleura and Expression of Vascular Endothelial Growth Factor/Vascular Permeability Factor by Human Lung Cancer Cells

    OpenAIRE

    Yano, Seiji; Shinohara, Hisashi; Herbst, Roy S; Kuniyasu, Hiroki; Bucana, Corazon D.; Ellis, Lee M.; Isaiah J. Fidler

    2000-01-01

    We determined the molecular mechanisms that regulate the pathogenesis of malignant pleural effusion (PE) associated with advanced stage of human, non-small-cell lung cancer. Intravenous injection of human PC14 and PC14PE6 (adenocarcinoma) or H226 (squamous cell carcinoma) cells into nude mice yielded numerous lung lesions. PC14 and PC14PE6 lung lesions invaded the pleura and produced PE containing a high level of vascular endothelial growth factor (VEGF)-localized vascular hyperpermeability. ...

  10. Tissue engineered pre-vascularized buccal mucosa equivalents utilizing a primary triculture of epithelial cells, endothelial cells and fibroblasts.

    Science.gov (United States)

    Heller, M; Frerick-Ochs, E V; Bauer, H-K; Schiegnitz, E; Flesch, D; Brieger, J; Stein, R; Al-Nawas, B; Brochhausen, C; Thüroff, J W; Unger, R E; Brenner, W

    2016-01-01

    Artificial generated buccal mucosa equivalents are a promising approach for the reconstruction of urethral defects. Limiting in this approach is a poor blood vessel supply after transplantation, resulting in increased morbidity and necrosis. We generated a pre-vascularized buccal mucosa equivalent in a tri-culture of primary buccal epithelial cells, fibroblasts and microvascular endothelial cells, using a native collagen membrane as a scaffold. A successful pre-vascularization and dense formation of capillary-like structures at superficial areas was demonstrated. The lumen size of pre-formed blood vessels corresponded to the capillary size in vivo (10-30 μm). Comparing native with a highly cross-linked collagen membrane we found a distinct higher formation of capillary-like structures on the native membrane, apparently caused by higher secretion of angiogenic factors such as PDGF, IL-8 and angiopoietin by the cells. These capillary-like structures became functional blood vessels through anastomosis with the host vasculature after implantation in nude mice. This in vitro method should result in an accelerated blood supply to the biomaterial with cells after transplantation and increase the succes rates of the implant material. PMID:26606446

  11. 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

  12. Investigation of the basic physics of high efficiency semiconductor hot carrier solar cell

    Science.gov (United States)

    Alfano, R. R.; Wang, W. B.; Mohaidat, J. M.; Cavicchia, M. A.; Raisky, O. Y.

    1995-01-01

    The main purpose of this research program is to investigate potential semiconductor materials and their multi-band-gap MQW (multiple quantum wells) structures for high efficiency solar cells for aerospace and commercial applications. The absorption and PL (photoluminescence) spectra, the carrier dynamics, and band structures have been investigated for semiconductors of InP, GaP, GaInP, and InGaAsP/InP MQW structures, and for semiconductors of GaAs and AlGaAs by previous measurements. The barrier potential design criteria for achieving maximum energy conversion efficiency, and the resonant tunneling time as a function of barrier width in high efficiency MQW solar cell structures have also been investigated in the first two years. Based on previous carrier dynamics measurements and the time-dependent short circuit current density calculations, an InAs/InGaAs - InGaAs/GaAs - GaAs/AlGaAs MQW solar cell structure with 15 bandgaps has been designed. The absorption and PL spectra in InGaAsP/InP bulk and MQW structures were measured at room temperature and 77 K with different pump wavelength and intensity, to search for resonant states that may affect the solar cell activities. Time-resolved IR absorption for InGaAsP/InP bulk and MQW structures has been measured by femtosecond visible-pump and IR-probe absorption spectroscopy. This, with the absorption and PL measurements, will be helpful to understand the basic physics and device performance in multi-bandgap InAs/InGaAs - InGaAs/InP - InP/InGaP MQW solar cells. In particular, the lifetime of the photoexcited hot electrons is an important parameter for the device operation of InGaAsP/InP MQW solar cells working in the resonant tunneling conditions. Lastly, time evolution of the hot electron relaxation in GaAs has been measured in the temperature range of 4 K through 288 K using femtosecond pump-IR-probe absorption technique. The temperature dependence of the hot electron relaxation time in the X valley has been measured.

  13. Study on performance of magnetic fluorescent nanoparticles as gene carrier and location in pig kidney cells

    Science.gov (United States)

    Wang, Yan; Cui, Haixin; Sun, Changjiao; Du, Wei; Cui, Jinhui; Zhao, Xiang

    2013-03-01

    We evaluated the performance of green fluorescent magnetic Fe3O4 nanoparticles (NPs) as gene carrier and location in pig kidney cells. When the mass ratio of NPs to green fluorescent protein plasmid DNA reached 1:16 or above, DNA molecules can be combined completely with NPs, which indicates that the NPs have good ability to bind negative DNA. Atomic force microscopy (AFM) experiments were carried out to investigate the binding mechanism between NPs and DNA. AFM images show that individual DNA strands come off of larger pieces of netlike agglomerations and several spherical nanoparticles are attached to each individual DNA strand and interact with each other. The pig kidney cells were labelled with membrane-specific red fluorescent dye 1,1'-dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine perchlorate and nucleus-specific blue fluorescent dye 4',6-diamidino-2-phenylindole dihydrochloride. We found that green fluorescent nanoparticles can past the cell membrane and spread throughout the interior of the cell. The NPs seem to locate more frequently in the cytoplasm than in the nucleus.

  14. Polydopamine-Decorated Sticky, Water-Friendly, Biodegradable Polycaprolactone Cell Carriers.

    Science.gov (United States)

    Kim, Minhee; Kim, Jung-Suk; Lee, Haeshin; Jang, Jae-Hyung

    2016-05-01

    A bioinspired adhesive material, polydopamine (pDA), was employed as an interfacial glue to stably immobilize human neural stem cells (hNSCs) on the external surface of biodegradable polycaprolactone (PCL) microspheres, thereby serving as versatile key systems that can be used for cell carriers. The pDA decoration on the PCL microspheres has been resulted in robust hNSC immobilization as well as proliferation on their curved surfaces. The pDA coating has transformed the hydrophobic PCL systems toward water-friendly and sticky characteristics, thereby resulting in full dispersion in aqueous solution and stable adherence onto a wet biological surface. Adeno-associated virus, a safe gene vector capable of effectively regulating cell behaviors, can be decorated on the PCL surfaces and delivered efficiently to hNSCs adhered to the microsphere exteriors. These distinctive multiple benefits of the sticky pDA microspheres can provide core technologies that can boost the therapeutic effects of cell therapy approaches. PMID:26799057

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

    International Nuclear Information System (INIS)

    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

  16. Local electromechanical properties of different phenotype models of vascular smooth muscle cells using force microscopy

    Science.gov (United States)

    Thompson, Gary; Reukov, Vladimir; Nikiforov, Maxim; Guo, Senli; Ovchinnikov, Oleg; Jesse, Stephen; Kalinin, Sergei; Vertegel, Alexey

    2010-03-01

    Vascular smooth muscle cells (VSMCs) exist as a spectrum of diverse phenotypes raning between contractile and synthetic, the latter being associated with disease states. Different VSMC phenotypes, modeled using serum-starvation, exhibit characteristic electromechanical responses that can be distinguished using band excitation piezoresponse force microscopy (BEPFM), which maps information at the same rate as the atomic force microscope (AFM) scan performed simultaneously. BEPFM image formation mechanism in the culture medium is determined using excitation steps from 1 mV to 100 V. High voltage improves contrast between cells and collagen-coated substrates. Viscoelasticity from AFM stress relaxation experiments and local elasticity from force maps correlate to BEPFM data providing a map of local mechanical properties on different VSMCs.

  17. Role of chemokine RANTES in the regulation of perivascular inflammation, T-cell accumulation, and vascular dysfunction in hypertension

    OpenAIRE

    Mikolajczyk, T.P.; Nosalski, R.; Szczepaniak, P.; Budzyn, K; Osmenda, G.; Skiba, D; A. SAGAN; Wu, J.; Vinh, A.; Marvar, P. J.; Guzik, B.; Podolec, J.; Drummond, G.; Lob, H. E.; Harrison, D.G.

    2016-01-01

    Recent studies have emphasized the role of perivascular inflammation in cardiovascular disease. We studied mechanisms of perivascular leukocyte infiltration in angiotensin II (Ang II)-induced hypertension and their links to vascular dysfunction. Chronic Ang II infusion in mice increased immune cell content of T cells (255 ± 130 to 1664 ± 349 cells/mg; P < 0.01), M1 and M2 macrophages, and dendritic cells in perivascular adipose tissue. In particular, the content of T lymphocytes bearing C...

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

    Directory of Open Access Journals (Sweden)

    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.

  19. Preparation of bone marrow stromal cell antigen 2 targeted microbubbles and ultrasound molecular imaging for tumor vascular endothelial cells

    International Nuclear Information System (INIS)

    Objective: To prepare the bone marrow stromal cell antigen 2 (BST2)-targeted micro-bubbles (BST2-TMBs) for detecting the vascular endothelial cells of tumor via ultrasound molecular imaging technology. Methods: The targeted microbubbles (BST2-TMBs) were obtained through linking anti-BST2 antibodies to the surface of microbubbles via biotin-avidin bridge. The morphology of TMBs was examined under microscope and size distribution was observed using an optical particle counter. The specific binding of TMBs to endothelial cells was detected by in vitro cell adhesion assay. Murine prostatic carcinoma was used to investigate the capability of TMBs in detecting the vascular endothelial cells and for validating the expression of BST2 proteins. The t test was used by SPSS 19.0 to analyze the data. Results: The targeted microbubbles had the mean diameter of 1.61 μm, with 95% microbubbles between 1 to 5 μm. The in vitro cell adhesion assay demonstrated that the TMBs were able to specifically bind to the surface of endothelial cells, with (165 ±25) TMBs per field of view,significantly higher than that of the non-targeted microbubbles ((10 ± 3) microbubbles per field of view, t=10.662, P<0.01). The enhancement of ultrasonic signals of these cells bound with TMBs was also observed (TMBs: 27.93 ± 5.14 (gray-level), non-targeted microbubbles: 3.61 ± 1.67 (gray-level) ; t=7.239, P<0.01). Significant enhancement of signal intensity (gray-level: 38.79 ±0.29 at 7 min, remaining 47.65% of that (81.40 ±0.37) at 30 s) was found in the tumors of mice injected with BST2-TMBs, which was 4.27-fold higher than that (gray-level: 9.46 ±0.17 at 7 min, remaining 11.39% of that (83.01 ± 0.60) at 30 s) of mice injected with non-targeted microbubbles (t=65.587, P<0.01). This finding was further confirmed through immunohistochemistry assay. Conclusion: BST2-TMBs can be used for detecting the vascular endothelial cells of tumors via ultrasound molecular imaging. (authors)

  20. Bisphenol A Disrupts Transcription and Decreases Viability in Aging Vascular Endothelial Cells

    Directory of Open Access Journals (Sweden)

    Edna Ribeiro-Varandas

    2014-09-01

    Full Text Available Bisphenol A (BPA is a widely utilized endocrine disruptor capable of mimicking endogenous hormones, employed in the manufacture of numerous consumer products, thereby interfering with physiological cellular functions. Recent research has shown that BPA alters epigenetic cellular mechanisms in mammals and may be correlated to enhanced cellular senescence. Here, the effects of BPA at 10 ng/mL and 1 µg/mL, concentrations found in human samples, were analyzed on HT29 human colon adenocarcinona cell line and Human Umbilical Vein Endothelial Cells (HUVEC. Quantitative Real-Time Polymerase Chain Reaction (qRT-PCR transcriptional analysis of the Long Interspersed Element-1 (LINE-1 retroelement showed that BPA induces global transcription deregulation in both cell lines, although with more pronounced effects in HUVEC cells. Whereas there was an increase in global transcription in HT29 exclusively after 24 h of exposure, this chemical had prolonged effects on HUVEC. Immunoblotting revealed that this was not accompanied by alterations in the overall content of H3K9me2 and H3K4me3 epigenetic marks. Importantly, cell viability assays and transcriptional analysis indicated that prolonged BPA exposure affects aging processes in senescent HUVEC. To our knowledge this is the first report that BPA interferes with senescence in primary vascular endothelial cells, therefore, suggesting its association to the etiology of age-related human pathologies, such as atherosclerosis.

  1. Modelling tumour cell proliferation from vascular structure using tissue decomposition into avascular elements.

    Science.gov (United States)

    Besenhard, Maximilian O; Jarzabek, Monika; O'Farrell, Alice C; Callanan, John J; Prehn, Jochen Hm; Byrne, Annette T; Huber, Heinrich J

    2016-08-01

    Computer models allow the mechanistically detailed study of tumour proliferation and its dependency on nutrients. However, the computational study of large vascular tumours requires detailed information on the 3-dimensional vessel network and rather high computation times due to complex geometries. This study puts forward the idea of partitioning vascularised tissue into connected avascular elements that can exchange cells and nutrients between each other. Our method is able to rapidly calculate the evolution of proliferating as well as dead and quiescent cells, and hence a proliferative index, from a given amount and distribution of vascularisation of arbitrary complexity. Applying our model, we found that a heterogeneous vessel distribution provoked a higher proliferative index, suggesting increased malignancy, and increased the amount of dead cells compared to a more static tumour environment when a homogenous vessel distribution was assumed. We subsequently demonstrated that under certain amounts of vascularisation, cell proliferation may even increase when vessel density decreases, followed by a subsequent decrease of proliferation. This effect was due to a trade-off between an increase in compensatory proliferation for replacing dead cells and a decrease of cell population due to lack of oxygen supply in lowly vascularised tumours. Findings were illustrated by an ectopic colorectal cancer mouse xenograft model. Our presented approach can be in the future applied to study the effect of cytostatic, cytotoxic and anti-angiogenic chemotherapy and is ideally suited for translational systems biology, where rapid interaction between theory and experiment is essential. PMID:27155046

  2. Bisphenol A Disrupts Transcription and Decreases Viability in Aging Vascular Endothelial Cells

    Science.gov (United States)

    Ribeiro-Varandas, Edna; Pereira, H. Sofia; Monteiro, Sara; Neves, Elsa; Brito, Luísa; Boavida Ferreira, Ricardo; Viegas, Wanda; Delgado, Margarida

    2014-01-01

    Bisphenol A (BPA) is a widely utilized endocrine disruptor capable of mimicking endogenous hormones, employed in the manufacture of numerous consumer products, thereby interfering with physiological cellular functions. Recent research has shown that BPA alters epigenetic cellular mechanisms in mammals and may be correlated to enhanced cellular senescence. Here, the effects of BPA at 10 ng/mL and 1 µg/mL, concentrations found in human samples, were analyzed on HT29 human colon adenocarcinona cell line and Human Umbilical Vein Endothelial Cells (HUVEC). Quantitative Real-Time Polymerase Chain Reaction (qRT-PCR) transcriptional analysis of the Long Interspersed Element-1 (LINE-1) retroelement showed that BPA induces global transcription deregulation in both cell lines, although with more pronounced effects in HUVEC cells. Whereas there was an increase in global transcription in HT29 exclusively after 24 h of exposure, this chemical had prolonged effects on HUVEC. Immunoblotting revealed that this was not accompanied by alterations in the overall content of H3K9me2 and H3K4me3 epigenetic marks. Importantly, cell viability assays and transcriptional analysis indicated that prolonged BPA exposure affects aging processes in senescent HUVEC. To our knowledge this is the first report that BPA interferes with senescence in primary vascular endothelial cells, therefore, suggesting its association to the etiology of age-related human pathologies, such as atherosclerosis. PMID:25207595

  3. Mesoporous silica particle-PLA-PANI hybrid scaffolds for cell-directed intracellular drug delivery and tissue vascularization

    Science.gov (United States)

    Shokry, Hussein; Vanamo, Ulriika; Wiltschka, Oliver; Niinimäki, Jenni; Lerche, Martina; Levon, Kalle; Linden, Mika; Sahlgren, Cecilia

    2015-08-01

    Instructive materials are expected to revolutionize stem cell based tissue engineering. As many stem cell cues have adverse effects on normal tissue homeostasis, there is a need to develop bioactive scaffolds which offer locally retained and cell-targeted drug delivery for intracellular release in targeted cell populations. Further, the scaffolds need to support vascularization to promote tissue growth and function. We have developed an electrospun PLA-PANI fiber scaffold, and incorporated mesoporous silica nanoparticles within the scaffold matrix to obtain cell-targeted and localized drug delivery. The isotropy of the scaffold can be tuned to find the optimal morphology for a given application and the scaffold is electroactive to support differentiation of contractile tissues. We demonstrate that there is no premature drug release from particles under physiological conditions over a period of one week and that the drug is released upon internalization of particles by cells within the scaffold. The scaffold is biocompatible, supports muscle stem cell differentiation and cell-seeded scaffolds are vascularized in vivo upon transplantation on the chorioallantoic membrane of chicken embryos. The scaffold is a step towards instructive biomaterials for local control of stem cell differentiation, and tissue formation supported by vascularization and without adverse effects on the homeostasis of adjacent tissues due to diffusion of biological cues.Instructive materials are expected to revolutionize stem cell based tissue engineering. As many stem cell cues have adverse effects on normal tissue homeostasis, there is a need to develop bioactive scaffolds which offer locally retained and cell-targeted drug delivery for intracellular release in targeted cell populations. Further, the scaffolds need to support vascularization to promote tissue growth and function. We have developed an electrospun PLA-PANI fiber scaffold, and incorporated mesoporous silica nanoparticles within

  4. Cadmium Toxicity on Arterioles Vascular Smooth Muscle Cells of Spontaneously Hypertensive Rats

    Directory of Open Access Journals (Sweden)

    Elbert L. Myles

    2006-12-01

    Full Text Available Cadmium (Cd is frequently used in various industrial applications and is a ubiquitous environmental toxicant, also present in tobacco smoke. An important route of exposure is the circulatory system whereas blood vessels are considered to be main stream organs of Cd toxicity. Our previous results indicate that cadmium chloride (CdCl2 affects mean arterial blood pressure in hypertensive rats. We hypothesized that Cd alters the intracellular calcium transient mechanism, by cadmium-induced stimulation of MAPKs (ERK 1 & 2 which is mediated partially through calcium-dependent PKC mechanism. To investigate this hypothesis, we exposed primary cultures of vascular smooth muscle cells (VSMCs from wistar kyoto (WKY and spontaneously hypertensive rats (SHR to increased concentrations of CdCl2 on cell viability, expression of mitogen-activated protein kinases (MAPKs/ERK 1 & 2, and protein kinase C (PKC which are activated by Cd in several cell types. The results from these studies indicate that CdCl2 decreased cell viability of both SHR and WKY VSMCs in a concentration dependent-manner. Viability of both cell types decreased 33±5.3 (SHR and 39±2.3% (WKY when exposed to 1 μM CdCl2, whereas, 8 and 16 μM reduced viability by 66±3.1 and 62±4.5% in SHR cells. CdCl2 increased ERK 1 & 2 in a biphasic manner with maximum increase occurring when cells are exposed to 1 and 4 μM in SHR VSMCs, whereas, a reduction in ERK 1 and 2 is observed when WKY cells are treated with 2 μM. The results also indicate that CdCl2 increased PKC a/ß in both SHR and WKY VSMCs with a greater increase in expression in SHR VSMCs. In addition, the [Ca2+]i chelator, BAPTA, suppressed the CdCl2 effect, whereas, the PKC inhibitor, GF109203X, reduced the CdCl2 induced-effect on PKC expression. The present studies support the hypothesis that Cd can be a risk factor of hypertension through dysfunction of vascular smooth muscle cells

  5. Effect of oxygen precipitates in solar grade silicon on minority carrier lifetime and efficiency of solar cells

    Institute of Scientific and Technical Information of China (English)

    SUN Haizhi; LIU Caichi; HAO Qiuyan; WANG Lijian

    2006-01-01

    The effect of oxygen precipitates on minority carrier lifetime and performance of solar cell was studied by means of Fourier Transform Infrared Spectroscopy (FTIR), quasi-steady state photoconductance (QSSPCD), optical microscope, spectrumresponse and solar cell efficiency test. The minority carrier lifetime and performance of solar cell reduced depend on oxygen precipitates. A few of oxygen precipitates have formed after single-step annealing; and they do not impact the efficiency dramatically. Pre-annealing at 650 ℃ for 4 h enhances the oxygen precipitation when it is subjected to middle temperature annealing. The solar cells performance decayed sharply. Especially annealing at 950 ℃ for 3 h, the V os and I sc of cells decrease 12% and 25% respectively. Few oxygen precipitates have formed in silicon after high temperature annealing at about 1050 ℃ whether pre-annealing is used or not, and the performance of cells is notbe affected.

  6. Circulating Endothelial Progenitor Cells and the Risk of Vascular Events after Ischemic Stroke

    Science.gov (United States)

    Martí-Fàbregas, Joan; Delgado-Mederos, Raquel; Crespo, Javier; Peña, Esther; Marín, Rebeca; Jiménez-Xarrié, Elena; Fernández-Arcos, Ana; Pérez-Pérez, Jesús; Martínez-Domeño, Alejandro; Camps-Renom, Pol; Prats-Sánchez, Luís; Casoni, Francesca; Badimon, Lina

    2015-01-01

    Background and Purpose We evaluated the hypothesis that the number of circulating EPC could be associated with the risk of stroke recurrence (SR) or vascular events (VE) after an ischemic stroke. Methods We studied prospectively consecutive patients with cerebral infarction within the first 48 hours after the onset. We recorded demographic factors, vascular risk factors, previous Rankin scale (RS) score, and etiology. We analyzed EPC counts by flow cytometry in blood collected at day 7 and defined EPC as CD34+/CD133+/KDR+ cells. Mean follow-up was 29.3 ± 16 months. We evaluated SR as well as VE. Patients were classified as to the presence or absence of EPC in the circulation (either EPC+ or EPC-). Bivariate analyses, Kaplan-Meier survival curves and Cox regression models were used. Results We included 121 patients (mean age 70.1±12.6 years; 65% were men). The percentage of EPC+ patients was 47.1%. SR occurred in 12 (9.9%) and VE in 18 (14.9%) patients. SR was associated significantly with a worse prior RS score, previous stroke and etiology, but not with EPC count. VE were associated significantly with EPC-, worse prior RS score, previous stroke, high age, peripheral artery disease and etiology. Cox regression model showed that EPC- (HR 7.07, p=0.003), age (HR 1.08, p=0.004) and a worse prior RS score (HR 5.8, p=0.004) were associated significantly with an increased risk of VE. Conclusions The absence of circulating EPC is not associated with the risk of stroke recurrence, but is associated with an increased risk of future vascular events. PMID:25874380

  7. REDV Peptide Conjugated Nanoparticles/pZNF580 Complexes for Actively Targeting Human Vascular Endothelial Cells.

    Science.gov (United States)

    Shi, Changcan; Li, Qian; Zhang, Wencheng; Feng, Yakai; Ren, Xiangkui

    2015-09-16

    Herein, we demonstrate that the REDV peptide modified nanoparticles (NPs) can serve as a kind of active targeting gene carrier to condensate pZNF580 for specific promotion of the proliferation of endothelial cells (ECs). First, we synthesized a series of biodegradable amphiphilic copolymers by ring-opening polymerization reaction and graft modification with REDV peptide. Second, we prepared active targeting NPs via self-assembly of the amphiphilic copolymers using nanoprecipitation technology. After condensation with negatively charged pZNF580, the REDV peptide modified NPs/pZNF580 complexes were formed finally. Due to the binding affinity toward ECs of the specific peptide, these REDV peptide modified NPs/pZNF580 complexes could be recognized and adhered specifically by ECs in the coculture system of ECs and human artery smooth muscle cells (SMCs) in vitro. After expression of ZNF580, as the key protein to promote the proliferation of ECs, the relative ZNF580 protein level increased from 15.7% to 34.8%. The specificity in actively targeting ECs of the REDV peptide conjugated NPs/pZNF580 complexes was still retained in the coculture system. These findings in the present study could facilitate the development of actively targeting gene carriers for the endothelialization of artificial blood vessels. PMID:26373583

  8. Artesunate Reduces Proliferation, Interferes DNA Replication and Cell Cycle and Enhances Apoptosis in Vascular Smooth Muscle Cells

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    This study examined the effect of artesunate (Art) on the proliferation, DNA replication, cell cycles and apoptosis of vascular smooth muscle cells (VSMCs). Primary cultures of VSMCs were established from aortas of mice and artesunate of different concentrations was added into the medium. The number of VSMCs was counted and the curve of cell growth was recorded.The activity of VSMCs was assessed by using MTT method and inhibitory rate was calculated.DNA replication was evaluated by [3 H]-TdR method and apoptosis by DNA laddering and HE staining. Flowmetry was used for simultaneous analysis of cell apoptosis and cell cycles. Compared with the control group, VSMCs proliferation in Art interfering groups were inhibited and [3H]-TdR incorprating rate were decreased as well as cell apoptosis was induced. The progress of cell cycle was blocked in G0/G1 by Art in a dose-dependent manner. It is concluded that Art inhibits VSMCs proliferation by disturbing DNA replication, inducing cell apoptosis and blocking cell cycle in G0/G1 phase.

  9. The New Role of CD163 in the Differentiation of Bone Marrow Stromal Cells into Vascular Endothelial-Like Cells

    Directory of Open Access Journals (Sweden)

    Wei Lu

    2016-01-01

    Full Text Available Bone marrow stromal cells (BMSCs can differentiate into vascular endothelial cells (VECs. It is regarded as an important solution to cure many diseases, such as ischemic diseases and diabetes. However, the mechanisms underlying BMSC differentiation into VECs are not well understood. Recent reports showed that CD163 expression was associated with angiogenesis. In this study, overexpression of CD163 in BMSCs elevated the protein level of the endothelial-associated markers CD31, Flk-1, eNOS, and VE-cadherin, significantly increased the proportion of Alexa Fluor 488-acetylated-LDL-positive VECs, and promoted angiogenesis on Matrigel. Furthermore, we demonstrated that CD163 acted downstream homeobox containing 1 (Hmbox1 and upstream fibroblast growth factor 2 (FGF-2. These data suggested that CD163 was involved in Hmbox1/CD163/FGF-2 signal pathway in BMSC differentiation into vascular endothelial-like cells. We found a new signal pathway and a novel target for further investigating the gene control of BMSC differentiation into a VEC lineage.

  10. The New Role of CD163 in the Differentiation of Bone Marrow Stromal Cells into Vascular Endothelial-Like Cells.

    Science.gov (United States)

    Lu, Wei; Su, Le; Yu, Zhezheng; Zhang, Shangli; Miao, Junying

    2016-01-01

    Bone marrow stromal cells (BMSCs) can differentiate into vascular endothelial cells (VECs). It is regarded as an important solution to cure many diseases, such as ischemic diseases and diabetes. However, the mechanisms underlying BMSC differentiation into VECs are not well understood. Recent reports showed that CD163 expression was associated with angiogenesis. In this study, overexpression of CD163 in BMSCs elevated the protein level of the endothelial-associated markers CD31, Flk-1, eNOS, and VE-cadherin, significantly increased the proportion of Alexa Fluor 488-acetylated-LDL-positive VECs, and promoted angiogenesis on Matrigel. Furthermore, we demonstrated that CD163 acted downstream homeobox containing 1 (Hmbox1) and upstream fibroblast growth factor 2 (FGF-2). These data suggested that CD163 was involved in Hmbox1/CD163/FGF-2 signal pathway in BMSC differentiation into vascular endothelial-like cells. We found a new signal pathway and a novel target for further investigating the gene control of BMSC differentiation into a VEC lineage. PMID:26880943

  11. Charge carrier dynamics and surface plasmon interaction in gold nanorod-blended organic solar cell

    Science.gov (United States)

    Rana, Aniket; Gupta, Neeraj; Lochan, Abhiram; Sharma, G. D.; Chand, Suresh; Kumar, Mahesh; Singh, Rajiv K.

    2016-08-01

    The inclusion of plasmonic nanoparticles into organic solar cell enhances the light harvesting properties that lead to higher power conversion efficiency without altering the device configuration. This work defines the consequences of the nanoparticle overloading amount and energy transfer process between gold nanorod and polymer (active matrix) in organic solar cells. We have studied the hole population decay dynamics coupled with gold nanorods loading amount which provides better understanding about device performance limiting factors. The exciton and plasmon together act as an interacting dipole; however, the energy exchange between these two has been elucidated via plasmon resonance energy transfer (PRET) mechanism. Further, the charge species have been identified specifically with respect to their energy levels appearing in ultrafast time domain. The specific interaction of these charge species with respective surface plasmon resonance mode, i.e., exciton to transverse mode of oscillation and polaron pair to longitudinal mode of oscillations, has been explained. Thus, our analysis reveals that PRET enhances the carrier population density in polymer via non-radiative process beyond the concurrence of a particular plasmon resonance oscillation mode and polymer absorption range. These findings give new insight and reveal specifically the factors that enhance and control the performance of gold nanorods blended organic solar cells. This work would lead in the emergence of future plasmon based efficient organic electronic devices.

  12. Carrier extraction behaviour in type II GaSb/GaAs quantum ring solar cells

    International Nuclear Information System (INIS)

    The introduction of quantum dot (QD) or quantum ring (QR) nanostructures into GaAs single-junction solar cells has shown enhanced photo-response above the GaAs absorption edge, because of sub-bandgap photon absorption. However, to further improve solar cell performance a better understanding of the mechanisms of photogenerated carrier extraction from QDs and QRs is needed. In this work we have used a direct excitation technique to study type II GaSb/GaAs quantum ring solar cells using a 1064 nm infrared laser, which enables us to excite electron–hole pairs directly within the GaSb QRs without exciting the GaAs host material. Temperature and laser intensity dependence of the current–voltage characteristics revealed that the thermionic emission process produced the dominant contribution to the photocurrent and accounts for 98.9% of total photocurrent at 0 V and 300 K. Although the tunnelling process gives only a low contribution to the photocurrent, an enhancement of the tunnelling current was clearly observed when an external electric field was applied. (paper)

  13. Evaluation of a mPEG-polyester-based hydrogel as cell carrier for chondrocytes.

    Science.gov (United States)

    Peng, Sydney; Yang, Shu-Rui; Ko, Chao-Yin; Peng, Yu-Shiang; Chu, I-Ming

    2013-11-01

    Temperature-sensitive hydrogels are attractive alternatives to porous cell-seeded scaffolds and is minimally invasive through simple injection and in situ gelling. In this study, we compared the performance of two types of temperature-sensitive hydrogels on chondrocytes encapsulation for the use of tissue engineering of cartilage. The two hydrogels are composed of methoxy poly(ethylene glycol)- poly(lactic-co-valerolactone) (mPEG-PVLA), and methoxy poly(ethylene glycol)-poly(lactic- co-glycolide) (mPEG-PLGA). Osmolarity and pH were optimized through the manipulation of polymer concentration and dispersion medium. Chondrocytes proliferation in mPEG-PVLA hydrogels was observed as well as accumulation of GAGs and collagen. On the other hand, chondrocytes encapsulated in mPEG-PLGA hydrogels showed low viability and chondrogenesis. Also, mPEG-PVLA hydrogel, which is more hydrophobic, retained physical integrity after 14 days while mPEG-PLGA hydrogel underwent full degradation due to faster hydrolysis rate and more pronounced acidic self-catalyzed degradation. The mPEG-PVLA hydrogel can be furthered tuned by manipulation of molecular weights to obtain hydrogels with different swelling and degradation characteristics, which may be useful as producing a selection of hydrogels compatible with different cell types. Taken together, these results demonstrate that mPEG-PVLA hydrogels are promising to serve as three-dimensional cell carriers for chondrocytes and potentially applicable in cartilage tissue engineering. PMID:24039062

  14. Plasma etching and its effect on minority charge carrier lifetimes and crystalline silicon solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Schaefer, S.; Lautenschlager, H.; Emanuel, G.; Luedemann, R. [Fraunhofer-Institut fuer Solare Energiesysteme (ISE), Freiburg im Breisgau (Germany)

    2000-07-01

    Reactive ion etching (RIE), microwave enhanced RIE (MW-RIE), and microwave downstream etching (MWDSE) are investigated in terms of plasma-induced damage and its impact on minority charge carrier lifetimes in p-type silicon and on silicon solar cells. Ion bombardment and the gas mixture are found to be the crucial parameters in order to control the plasma-induced damage caused by SF{sub 6}/O{sub 2} plasma etching. RIE as well as MW-RIE processes can be optimised in a way that only minimum damage occurs. It may be annealed during temperature steps in the solar cell process, though. Only by dispensing with ion bombardment as in MWDSE plasma-induced damage can be completely avoided. Surface recombination velocities of S<10 cm/s are measured on 1 {omega}cm float zone silicon after MWDSE and SiN{sub x} passivation. MWDSE can therefore be used to substitute standard wet chemical cleaning of wafer surfaces without any loss in solar cell performance. (orig.)

  15. Influence of Class I interferons on performance of vascular cells on stent material in vitro

    International Nuclear Information System (INIS)

    Purpose: Numerous reports suggest that Class 1 interferons (IFNs), particularly IFN-γ, inhibit migration and proliferation of different types of human cells. The objective of the present study was to determine the effect of Class I IFNs on viability and growth characteristics of human aortic endothelial cells (ECs), smooth muscle cells (SMC) and fibroblasts (FBs) in vitro. Methods: Stainless-steel (316-l) disks were coated with fibrin meshwork containing IFN-γ or IFN-α. The discs and IFN embedded meshwork were incubated with human EC, SMC and FB, and then cultured, whereas control cells were seeded onto uncoated surfaces or plain fibrin meshwork. Concentrations of recombinant IFN varied from 5 to 20 ng/cm2. Assessment of effect on cell viability, growth and attachment was performed utilizing Alamar Blue (AB) assay. Cell morphology was assessed by scanning electron microscopy (SEM). Results: We have now shown inhibitory capacity of IFN-γ on all three types of unstimulated cells. The growth-inhibitory effect was maximal with SMC, while it was minimal with FB and EC. IFN-γ abrogated mitogenic responses of SMC but not EC and partially FB to VEGF and FGF stimulation. IFN-α was able to inhibit EC growth and, to a lesser extent, FB, and did influence growth rates of SMC. Biochemical analysis of lactate dehydrogenase activity suggested that IFN was not toxic to vascular cells. We also measured the expression of cell adhesive molecules: P- and E-selections, PECAM and ICAM-1. These molecules were upregulated by IFN in EC. Media derived from quiescent human SMC displayed low immunoreactive elastase activity, while conditional media after IFN-γ treatment but not IFN-α treatment had approximately a threefold greater activity. Conclusion: These data suggest that IFN-γ significantly inhibits SMC growth in the absence of significant endothelial toxicity and is dose-dependent; however, animal experiments are needed to further explore the antirestenotic effects of IFNs

  16. Impact of carrier recombination on fill factor for large area heterojunction crystalline silicon solar cell with 25.1% efficiency

    Science.gov (United States)

    Adachi, Daisuke; Hernández, José Luis; Yamamoto, Kenji

    2015-12-01

    We have achieved a certified 25.1% conversion efficiency in a large area (151.9 cm2) heterojunction (HJ) crystalline Si (c-Si) solar cell with amorphous Si (a-Si) passivation layer. This efficiency is a world record in a both-side-contacted c-Si solar cell. Our high efficiency HJ c-Si solar cells are investigated from the standpoint of the effective minority carrier lifetime (τe), and the impact of τe on fill factor (FF) is discussed. The τe measurements of our high efficiency HJ c-Si solar cells reveal that τe at an injection level corresponding to an operation point of maximum power is dominated by the carrier recombination at the a-Si/c-Si interface. By optimization of the process conditions, the carrier recombination at the a-Si/c-Si interface is reduced, which leads to an improvement of the FF by an absolute value of 2.7%, and a conversion efficiency of 25.1% has been achieved. These results indicate that the reduction of carrier recombination centers at the a-Si/c-Si interface should be one of the most crucial issues for further improvement of FF even in the HJ c-Si solar cells with efficiency over 25%.

  17. Intercellular ultrafast Ca(2+) wave in vascular smooth muscle cells: numerical and experimental study.

    Science.gov (United States)

    Quijano, J C; Raynaud, F; Nguyen, D; Piacentini, N; Meister, J J

    2016-01-01

    Vascular smooth muscle cells exhibit intercellular Ca(2+) waves in response to local mechanical or KCl stimulation. Recently, a new type of intercellular Ca(2+) wave was observed in vitro in a linear arrangement of smooth muscle cells. The intercellular wave was denominated ultrafast Ca(2+) wave and it was suggested to be the result of the interplay between membrane potential and Ca(2+) dynamics which depended on influx of extracellular Ca(2+), cell membrane depolarization and its intercel- lular propagation. In the present study we measured experimentally the conduction velocity of the membrane depolarization and performed simulations of the ultrafast Ca(2+) wave along coupled smooth muscle cells. Numerical results reproduced a wide spectrum of experimental observations, including Ca(2+) wave velocity, electrotonic membrane depolarization along the network, effects of inhibitors and independence of the Ca(2+) wave speed on the intracellular stores. The numerical data also provided new physiological insights suggesting ranges of crucial model parameters that may be altered experimentally and that could significantly affect wave kinetics allowing the modulation of the wave characteristics experimentally. Numerical and experimental results supported the hypothesis that the propagation of membrane depolarization acts as an intercellular messenger mediating intercellular ultrafast Ca(2+) waves in smooth muscle cells. PMID:27507785

  18. Intercellular ultrafast Ca2+ wave in vascular smooth muscle cells: numerical and experimental study

    Science.gov (United States)

    Quijano, J. C.; Raynaud, F.; Nguyen, D.; Piacentini, N.; Meister, J. J.

    2016-01-01

    Vascular smooth muscle cells exhibit intercellular Ca2+ waves in response to local mechanical or KCl stimulation. Recently, a new type of intercellular Ca2+ wave was observed in vitro in a linear arrangement of smooth muscle cells. The intercellular wave was denominated ultrafast Ca2+ wave and it was suggested to be the result of the interplay between membrane potential and Ca2+ dynamics which depended on influx of extracellular Ca2+, cell membrane depolarization and its intercel- lular propagation. In the present study we measured experimentally the conduction velocity of the membrane depolarization and performed simulations of the ultrafast Ca2+ wave along coupled smooth muscle cells. Numerical results reproduced a wide spectrum of experimental observations, including Ca2+ wave velocity, electrotonic membrane depolarization along the network, effects of inhibitors and independence of the Ca2+ wave speed on the intracellular stores. The numerical data also provided new physiological insights suggesting ranges of crucial model parameters that may be altered experimentally and that could significantly affect wave kinetics allowing the modulation of the wave characteristics experimentally. Numerical and experimental results supported the hypothesis that the propagation of membrane depolarization acts as an intercellular messenger mediating intercellular ultrafast Ca2+ waves in smooth muscle cells. PMID:27507785

  19. Melatonin inhibits the expression of vascular endothelial growth factor in pancreatic cancer cells

    Institute of Scientific and Technical Information of China (English)

    Dong Lv; Pei-Lin Cui; Shi-Wei Yao; You-Qing Xu; Zhao-Xu Yang

    2012-01-01

    Objective:To investigate the effects of melatonin on cellular proliferation and endogenous vascular endothelial growth factor (VEGF) expression in pancreatic carcinoma cells (PANC-1).Methods:PANC-1 cells were cultured for this study.The secreted VEGF concentration in the culture medium was determined using ELISA method,VEGF production in the tumor cells was detected by immunocytochemistry,and VEGF mRNA expression was determined by RT-PCR.Results:Higher melatonin concentrations significantly inhibited cellular proliferation,with 1 mmol/L concentration exhibiting the highest inhibitory effect (P<0.01).VEGF concentrations in the cell culture supernatants and intra-cellules were all significantly reduced after melatonin (1 mmol/L) incubation (P<0.05).VEGF mRNA expression decreased markedly in a time-dependent manner during the observation period (P<0.05).Conclusions:High melatonin concentrations markedly inhibited the proliferation of pancreatic carcinoma cells.The endogenous VEGF expression was also suppressed by melatonin incubation.

  20. Effects of Vascular Endothelial Cell Growth Factor on Fibrovascular Ingrowth into Rabbit's Hydroxyapatite Orbital Implant

    Institute of Scientific and Technical Information of China (English)

    张虹; 李贵刚; 纪彩霓; 何花; 王军明; 胡维琨; 吴华; 陈憬

    2004-01-01

    Summary: The effects of different concentrations of vascular endothelial cell growth factor (VEGF)on the fibrovascular ingrowth into rabbits hydroxyapatite orbital implant were investigated. Twelve New Zealand white rabbits were divided into 3 groups and received hydroxyapatite orbital implant surgery in their right eyes. Before and after the operation, the implants were treated with 10 ng/ml VEGF, 100 ng/ml VEGF, or normal saline as control group. The animals received technetium bones scan at 2, 4, and 6 weeks postoperatively. The mean radioactivity counts within region of interest (ROI) of the surgery eye (R) and the non-surgery eye (L) in the same animal were tested,and the R/L ratios were calculated. The implants were harvested at 6th weeks and examined histopathologically. The results showed that at second week, there was no significant difference in mean R/L ratios between VEGF group and control group (F=2.83, P=0. 111);At 4th week (F=7. 728, P=0.011) and 6th week (F=7.831, P=0.011) postoperatively, the mean ratios in VEGF groups were significantly higher than that in control group. At 6th week postoperatively,the fibrovascularization rates in VEGF groups were higher than in control group significantly (F=8. 711, P = 0. 008), It was suggested that VEGF could promote the fibrovascular ingrowth into hydroxyapatite orbital implant, thus might shorten the time required for complete vascularization of the HA orbital implant.

  1. Critical Parameters of the In Vitro Method of Vascular Smooth Muscle Cell Calcification.

    Directory of Open Access Journals (Sweden)

    Luis Hortells

    Full Text Available Vascular calcification (VC is primarily studied using cultures of vascular smooth muscle cells. However, the use of very different protocols and extreme conditions can provide findings unrelated to VC. In this work we aimed to determine the critical experimental parameters that affect calcification in vitro and to determine the relevance to calcification in vivo.Rat VSMC calcification in vitro was studied using different concentrations of fetal calf serum, calcium, and phosphate, in different types of culture media, and using various volumes and rates of change. The bicarbonate content of the media critically affected pH and resulted in supersaturation, depending on the concentration of Ca2+ and Pi. Such supersaturation is a consequence of the high dependence of bicarbonate buffers on CO2 vapor pressure and bicarbonate concentration at pHs above 7.40. Such buffer systems cause considerable pH variations as a result of minor experimental changes. The variations are more critical for DMEM and are negligible when the bicarbonate concentration is reduced to ¼. Particle nucleation and growth were observed by dynamic light scattering and electron microscopy. Using 2mM Pi, particles of ~200nm were observed at 24 hours in MEM and at 1 hour in DMEM. These nuclei grew over time, were deposited in the cells, and caused osteogene expression or cell death, depending on the precipitation rate. TEM observations showed that the initial precipitate was amorphous calcium phosphate (ACP, which converts into hydroxyapatite over time. In blood, the scenario is different, because supersaturation is avoided by a tightly controlled pH of 7.4, which prevents the formation of PO43--containing ACP.The precipitation of ACP in vitro is unrelated to VC in vivo. The model needs to be refined through controlled pH and the use of additional procalcifying agents other than Pi in order to reproduce calcium phosphate deposition in vivo.

  2. Zoledronate upregulates MMP-9 and -13 in rat vascular smooth muscle cells by inducing oxidative stress

    Science.gov (United States)

    Arun, Mehmet Zuhuri; Reel, Buket; Sala-Newby, Graciela B; Bond, Mark; Tsaousi, Aikaterini; Maskell, Perry; Newby, Andrew C

    2016-01-01

    Background Bisphosphonates, including zoledronate, target osteoclasts and are widely used in the treatment of osteoporosis and other bone resorption diseases, despite side effects that include damaging the stomach epithelium. Beneficial and adverse effects on other organ systems, including the cardiovascular system, have also been described and could impact on the use of bisphosphonates as therapeutic agents. Vascular smooth muscle cells (VSMCs) are major constituents of the normal vascular wall and have a key role in intimal thickening and atherosclerosis, in part by secreting MMPs that remodel the extracellular matrix and cleave cell surface proteins or secreted mediators. In this study, we investigated the effects of zoledronate on MMP expression. Methods Rat VSMCs were stimulated by PDGF (50 ng/mL) plus TNF-α (10 ng/mL) or left unstimulated for a further 24 hours in serum-free medium. In other series of experiments, cells were pre-treated either with SC-514 (50 μM) or with apocynin (20 nM) for 2 hours, then zoledronate (100 μM) was added into 2% fetal calf serum containing medium for 24 hours. Results and discussion Using isolated rat VSMCs in culture, zoledronate (100 μM) increased MMP-9 and -13 mRNA expressions but inhibited MMP-2 expression. MMP-9 and MMP-13 up-regulation was shown to depend on the NF-κB pathway; and this was activated by zoledronate. Furthermore, zoledronate elevated the levels of reactive oxygen species detected by either dichlorofluorescein in isolated VSMCs or lucigenin enhanced chemiluminescence in rat aortic rings in vitro. Apocynin, an inhibitor of NADPH oxidase, reversed NF-κB activation and MMP-9 and MMP-13 up-regulation by zoledronate. Conclusion We conclude that zoledronate increases MMP-9 and MMP-13 expressions in rat VSMCs dependent upon stimulation of the NF-κB pathway by reactive oxygen species. Effects on MMP expression may contribute to the pharmacologic profile of bisphosphonates.

  3. Nuclear envelope proteins modulate proliferation of vascular smooth muscle cells during cyclic stretch application

    Science.gov (United States)

    Qi, Ying-Xin; Yao, Qing-Ping; Huang, Kai; Shi, Qian; Zhang, Ping; Wang, Guo-Liang; Han, Yue; Bao, Han; Wang, Lu; Li, Hai-Peng; Shen, Bao-Rong; Wang, Yingxiao; Chien, Shu; Jiang, Zong-Lai

    2016-01-01

    Cyclic stretch is an important inducer of vascular smooth muscle cell (VSMC) proliferation, which is crucial in vascular remodeling during hypertension. However, the molecular mechanism remains unclear. We studied the effects of emerin and lamin A/C, two important nuclear envelope proteins, on VSMC proliferation in hypertension and the underlying mechano-mechanisms. In common carotid artery of hypertensive rats in vivo and in cultured cells subjected to high (15%) cyclic stretch in vitro, VSMC proliferation was increased significantly, and the expression of emerin and lamin A/C was repressed compared with normotensive or normal (5%) cyclic stretch controls. Using targeted siRNA to mimic the repressed expression of emerin or lamin A/C induced by 15% stretch, we found that VSMC proliferation was enhanced under static and 5%-stretch conditions. Overexpression of emerin or lamin A/C reversed VSMC proliferation induced by 15% stretch. Hence, emerin and lamin A/C play critical roles in suppressing VSMC hyperproliferation induced by hyperstretch. ChIP-on-chip and MOTIF analyses showed that the DNAs binding with emerin contain three transcription factor motifs: CCNGGA, CCMGCC, and ABTTCCG; DNAs binding with lamin A/C contain the motifs CVGGAA, GCCGCYGC, and DAAGAAA. Protein/DNA array proved that altered emerin or lamin A/C expression modulated the activation of various transcription factors. Furthermore, accelerating local expression of emerin or lamin A/C reversed cell proliferation in the carotid artery of hypertensive rats in vivo. Our findings establish the pathogenetic role of emerin and lamin A/C repression in stretch-induced VSMC proliferation and suggest mechanobiological mechanism underlying this process that involves the sequence-specific binding of emerin and lamin A/C to specific transcription factor motifs. PMID:27114541

  4. Influence of 103Pd radioactive stent on apoptosis of vascular smooth muscle cells

    International Nuclear Information System (INIS)

    Objective: To evaluate the influence of 103Pd radioactive stent on apoptosis and its relative genes bcl-2 and bax in injured vascular media smooth muscle cells of rabbit abdominal arteries and to investigate the mechanism of 103Pd radioactive stent for preventing restenosis after angioplasty. Methods: Fifty male New Zealand rabbits were randomized into stent group and 103Pd stent group. Each group was subdivided into 5 sub-groups. Control group was set up. The study arteries were harvested at 3, 7, 14, 28 and 56 d after stenting and the pathomorphology, apoptosis analysis and in situ hybridization were performed to evaluate the expression of bcl-2 and bax mRNA. Results: The severity of the restenosis in 103Pd stent group was less than that of stent group. It was most obvious at the 56th day (P103Pd stent group had much more apoptosis of vascular smooth muscle cells than stent group did and reached the peak at the 7th day, (14.72±0.53)% vs (12.42±1.13)% (P103Pd stent group was much lower than that of stent group at 3 to 28 d. The difference was most obvious at the 28th day after stenting, (18.43± 0.67)% vs (21.55±0.93)% (P103Pd stent group was higher than that of stent group, the peak was at the 7th day, (11.17±0.94)% vs (9.30±1.01)%. The ratio of bcl-2/bax in 103Pd stent group was much lower than that of stent group at 3 to 28 d. Linear correlation analysis showed that there was significant negative correlation between bcl-2 mRNA and apoptosis. Between bax mRNA and apoptosis, the positive correlation was found (P103Pd radioactive stent induced more significant apoptosis in vascular media smooth muscle cells by promoting the expression of apoptosis related genes and relieved the expanding of restenosis

  5. Flk1+ and VE-cadherin+ endothelial cells derived from iPSCs recapitulates vascular development during differentiation and display similar angiogenic potential as ESC-derived cells.

    Directory of Open Access Journals (Sweden)

    Erin E Kohler

    Full Text Available RATIONALE: Induced pluripotent stem (iPS cells have emerged as a source of potentially unlimited supply of autologous endothelial cells (ECs for vascularization. However, the regenerative function of these cells relative to adult ECs and ECs derived from embryonic stem (ES cells is unknown. The objective was to define the differentiation characteristics and vascularization potential of Fetal liver kinase (Flk1(+ and Vascular Endothelial (VE-cadherin(+ ECs derived identically from mouse (mES and miPS cells. METHODS AND RESULTS: Naive mES and miPS cells cultured in type IV collagen (IV Col in defined media for 5 days induced the formation of adherent cell populations, which demonstrated similar expression of Flk1 and VE-cadherin and the emergence of EC progenies. FACS purification resulted in 100% Flk1(+ VE-cadherin(+ cells from both mES and miPS cells. Emergence of Flk1(+VE-cadherin(+ cells entailed expression of the vascular developmental transcription factor Er71, which bound identically to Flk1, VE-cadherin, and CD31 promoters in both populations. Immunostaining with anti-VE-cadherin and anti-CD31 antibodies and microscopy demonstrated the endothelial nature of these cells. Each cell population (unlike mature ECs organized into well-developed vascular structures in vitro and incorporated into CD31(+ neovessels in matrigel plugs implanted in nude mice in vivo. CONCLUSION: Thus, iPS cell-derived Flk1(+VE-cadherin(+ cells expressing the Er71 are as angiogenic as mES cell-derived cells and incorporate into CD31(+ neovessels. Their vessel forming capacity highlights the potential of autologous iPS cells-derived EC progeny for therapeutic angiogenesis.

  6. Cocaine mediated apoptosis of vascular cells as a mechanism for carotid artery dissection leading to ischemic stroke.

    Science.gov (United States)

    Dabbouseh, Noura M; Ardelt, Agnieszka

    2011-08-01

    In arterial dissection, blood may enter the arterial wall through an intimal tear, splitting the arterial wall and activating the coagulation cascade at the site of endothelial damage. Dissection of extracranial and intracranial vessels may lead to ischemic stroke through thromboembolic or hemodynamic mechanisms. Major blunt trauma or rapid acceleration-deceleration may cause dissection, but in patients with inherent arterial wall weakness, dissection can occur spontaneously or as a result of minor neck movement. Cocaine use has been associated with dissection of the aortic arch and coronary and renal arteries through cocaine-mediated hypertension. Recent preclinical studies have suggested, however, that cocaine may cause apoptosis of cells in the vascular wall. In this article, we postulate that cocaine may cause apoptosis of vascular endothelial and/or smooth muscle cells, thus weakening the vascular wall and resulting in a dissection-prone state. We review the literature and propose a biological basis for vasculopathy, vascular dissection, and ischemic stroke in the setting of cocaine use. Further research studies on vascular cells, as well as focused analysis of human pathological material, will be important in providing evidence for or against our hypotheses. PMID:21546166

  7. Molecular Control of Vascular Tube Morphogenesis and Stabilization: Regulation by Extracellular Matrix, Matrix Metalloproteinases, and Endothelial Cell-Pericyte Interactions

    Science.gov (United States)

    Davis, George E.; Stratman, Amber N.; Sacharidou, Anastasia

    Recent studies have revealed a critical role for both extracellular matrices and matrix metalloproteinases in the molecular control of vascular morphogenesis and stabilization in three-dimensional (3D) tissue environments. Key interactions involve endothelial cells (ECs) and pericytes, which coassemble to affect vessel formation, remodeling, and stabilization events during development and postnatal life. EC-pericyte interactions control extracellular matrix remodeling events including vascular basement membrane matrix assembly, a necessary step for endothelial tube maturation and stabilization. ECs form tube networks in 3D extracellular matrices in a manner dependent on integrins, membrane-type metalloproteinases, and the Rho GTPases, Cdc42 and Rac1. Recent work has defined an EC lumen signaling complex of proteins composed of these proteins that controls 3D matrix-specific signaling events required for these processes. The EC tube formation process results in the creation of a network of proteolytically generated vascular guidance tunnels. These tunnels are physical matrix spaces that regulate vascular tube remodeling and represent matrix conduits into which pericytes are recruited to allow dynamic cell-cell interactions with ECs. These dynamic EC-pericyte interactions induce vascular basement membrane matrix deposition, leading to vessel maturation and stabilization.

  8. Nanostructuring for enhanced absorption and carrier collection in CZTS-based solar cells: Coupled optical and electrical modeling

    Science.gov (United States)

    Abdelraouf, Omar A. M.; Allam, Nageh K.

    2016-04-01

    Earth-abundant Cu2ZnSnS4 (CZTS) is being considered as a potential photon-absorbing layer for low cost thin film solar cells. Nanostructured light trapping is recently investigated as a technique for enhancing the efficiency of CZTS solar cells. Herein, we used coupled electrical and optical modeling for different combinations of nanostructured CZTS solar cells to guide optimization of such nanostructures. The model is validated by a comparison of simulated I-V curves with previously reported experimental data. A very good agreement is achieved. Simulations are used to demonstrate that nanostructures can be tailored to maximize the absorption, carrier generation, carrier collection, and efficiency in CZTS solar cells. All proposed nanostructured solar cells showed enhancement in the overall conversion efficiency.

  9. Biodegradable double nanocapsule as a novel multifunctional carrier for drug delivery and cell imaging

    Directory of Open Access Journals (Sweden)

    Qian K

    2015-06-01

    Full Text Available Kun Qian,1,2 Jing Wu,1 Enqi Zhang,1 Yingge Zhang,3 Ailing Fu1 1School of Pharmaceutical Sciences, Southwest University, 2College of Plant Protection, Southwest University, Chongqing, People’s Republic of China; 3Institute of Pharmacology and Toxicology, Key Laboratory of Nanopharmacology and Nanotoxicology, Beijing Academy of Medical Sciences, Beijing, People’s Republic of China Abstract: Highly-efficient delivery of macromolecules into cells for both imaging and therapy (theranostics remains a challenge for the design of a delivery system. Here, we suggested a novel hybrid protein–lipid polymer nanocapsule as an effective and nontoxic drug delivery and imaging carrier. The biodegradable nanocapsules showed the typical double emulsion features, including fluorescently labeled bovine serum albumin shell, oil phase containing poly(lactic-co-glycolic acid and linoleic acid, and inner aqueous phase. The nanocapsules were spherical in shape, with an average size of about 180 nm. Proteins packed into the inner aqueous phase of the nanocapsules could be delivered into cells with high efficiency, and the fluorescence of the fluorescently labeled bovine serum albumin could be used for tracing the protein migration and cellular location. Further studies suggested that the co-delivery of transcription factor p53 and lipophilic drug paclitaxel with the nanocapsules acted synergistically to induce Hela cell apoptosis, and the fluorescence of apoptotic cells was clearly observed under a fluorescence microscope. Such multifunctional delivery system would have great potential applications in drug delivery and theranostic fields. Keywords: emulsion, protein transport, fluorescence labeling, theranostics, cell apoptosis

  10. Expression of thymidine kinase mediated by a novel non-viral delivery system under the control of vascular endothelial growth factor receptor 2 promoter selectively kills human umbilical vein endothelial cells

    Institute of Scientific and Technical Information of China (English)

    Ying Wang; Hui-Xiong Xu; Ming-De Lu; Qing Tang

    2008-01-01

    AIM: To investigate the killing efficiency of a recombinant plasmid containing a thymidine kinase (TK) domain insert driven by the vascular endothelial growth factor receptor 2 (VEGFR2) promoter (KDR) on vascular endothelial cells.METHODS: The KDR-TK fragment was extracted from pBluescript 11 KDR-TK plasmid by enzymatic digestion with XhoI and Sa/I. The enhanced green fluorescence protein (EGFP) carrier was extracted from pEGFP by the same procedure. The KDR-TK was inserted into the pEGFP carrier to construct pEGFP-KDR-TK. Using ultrasound irradiation and microbubble,pEGFP-KDR-TK was transferred into human umbilical vein endothelial cells (HUVECs). The transient infection rate was estimated by green fluorescent protein (GFP)expression. Transfected HUVECs, non-transfected HUVECs, and HepG2 cells were cultured in the presence of different concentrations of ganciclovir (GCV), and the killing efficacy of HSV-TK/GCV was analyzed by 3-[4,5-dimethylthiazol-2-yl]-2, 5-diphenyl tetrazolium bromide (MTr) assay.RESULTS: The recombinant pEGFP-KDR-TK was successfully constructed by inserting the KDR-TK fragment into the pEGFP carrier. Transfected HUVECs showed cytoplasmic green fluorescence, and the transient transfection rate was about 20.3%. Pools of G418-resistant cells exhibited a higher sensitivity to the prodrug/GCV compared to non-transfected HUVECs or non-transfected HepG2 cells, respectively.CONCLUSION: KDR promoter and the suicide gene/prodrug system mediated by diagnostic ultrasound combined with microbubble can significantly kill HUVECs.Such therapy may present a novel and attractive approach to target gene therapy on tumor vessels.

  11. Vascular Cures

    Science.gov (United States)

    ... our CEO Board of Directors Scientific Advisory Board History of Vascular Cures Impact Contact Us Vascular Disease What is Vascular Disease? Education and Awareness Vascular Diseases Abdominal Aortic Aneurysm Aortic ...

  12. Cell-Penetrating Peptides as Carriers for Oral Delivery of Biopharmaceuticals.

    Science.gov (United States)

    Kristensen, Mie; Nielsen, Hanne Mørck

    2016-02-01

    Oral delivery of biopharmaceuticals, for example peptides and proteins, constitutes a great challenge in drug delivery due to their low chemical stability and poor permeation across the intestinal mucosa, to a large extent limiting the mode of administration to injections, which is not favouring patient compliance. Nevertheless, cell-penetrating peptides (CPPs) have shown promising potential as carriers to overcome the epithelium, and this minireview highlights recent knowledge gained within the field of CPP-mediated transepithelial delivery of therapeutic peptides and proteins from the intestine. Two approaches may be pursued: co-administration of the carrier and therapeutic peptide in the form of complexes obtained by simple bulk mixing, or administration of covalent conjugates demanding more advanced production methodologies. These formulation approaches have their pros and cons, and which is to be preferred depends on the physicochemical properties of both the specific CPP and the specific cargo. In addition to the physical epithelial barrier, a metabolic barrier must be overcome in order to obtain CPP-mediated delivery of a cargo drug from the intestine, and a number of strategies have been employed to delay enzymatic degradation of the CPP. The mechanisms by which CPPs translocate across membranes are not fully understood, but possibly involve endocytosis as well as direct translocation, and the CPP-mediated transepithelial delivery of cargo drugs thus likely involves similar mechanisms for the initial membrane interaction and translocation. However, the mechanisms responsible for transcytosis of the cargo drug, if taken up by an endocytic mechanism, or direct translocation across the epithelium are so far not known. PMID:26525297

  13. Guanidinium: A Route to Enhanced Carrier Lifetime and Open-Circuit Voltage in Hybrid Perovskite Solar Cells.

    Science.gov (United States)

    Marco, Nicholas De; Zhou, Huanping; Chen, Qi; Sun, Pengyu; Liu, Zonghao; Meng, Lei; Yao, En-Ping; Liu, Yongsheng; Schiffer, Andy; Yang, Yang

    2016-02-10

    Hybrid perovskites have shown astonishing power conversion efficiencies owed to their remarkable absorber characteristics including long carrier lifetimes, and a relatively substantial defect tolerance for solution-processed polycrystalline films. However, nonradiative charge carrier recombination at grain boundaries limits open circuit voltages and consequent performance improvements of perovskite solar cells. Here we address such recombination pathways and demonstrate a passivation effect through guanidinium-based additives to achieve extraordinarily enhanced carrier lifetimes and higher obtainable open circuit voltages. Time-resolved photoluminescence measurements yield carrier lifetimes in guanidinium-based films an order of magnitude greater than pure-methylammonium counterparts, giving rise to higher device open circuit voltages and power conversion efficiencies exceeding 17%. A reduction in defect activation energy of over 30% calculated via admittance spectroscopy and confocal fluorescence intensity mapping indicates successful passivation of recombination/trap centers at grain boundaries. We speculate that guanidinium ions serve to suppress formation of iodide vacancies and passivate under-coordinated iodine species at grain boundaries and within the bulk through their hydrogen bonding capability. These results present a simple method for suppressing nonradiative carrier loss in hybrid perovskites to further improve performances toward highly efficient solar cells. PMID:26790037

  14. Effect of arsenic trioxide on vascular endothelial cell proliferation and expression of vascular endothelial growth factor receptors Flt-1 and KDR in gastric cancer in nude mice

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    AIM: To investigate the effect of arsenic trioxide (As2O3) on expression of vascular endothelial growth factor receptor-1 (VEGFR-1, Flt-1) and VEGFR-2 (KDR) in human gastric tumor cells and proliferation of vascular endothelial cells.METHODS: The solid tumor model was formed in nude mice with the gastric cancer cell line SGC-7901. The animals were treated with As2O3. Microvessel density (MVD) and expression of Flt-1 and KDR were detected by immunofluorescence laser confocal microscopy.SGC-7901 cells were treated respectively by exogenous recombinant human VEGF165 or VEGF165 + As2O3. Cell viability was measured by MTT assay. Cell viability of ECV304 cells was measured by MTT assay, and cell cycle and apoptosis were analyzed using flow cytometry.RESULTS: The tumor growth inhibition was 30.33% and 50.85%, respectively, in mice treated with As2O3 2.5 and 5 mg/kg. MVD was significantly lower in arsenic-treated mice than in the control group. The fluorescence intensity levels of Flt-1 and KDR were significantly less in the arsenic-treated mice than in the control group. VEGF165 may accelerate growth of SGC7901 cells, but As2O3 may disturb the stimulating effect of VEGF165. ECV304 cell growth was suppressed by 76.51%, 71.09% and 61.49% after 48 h treatment with As2O3 at 0.5, 2.5 and 5 μmol/L, respectively. Early apoptosis in the As2O3-treated mice was 2.88-5.1 times higher than that in the controls, and late apoptosis was 1.17-1.67 times higher than that in the controls.CONCLUSION: Our results showed that As2O3 delays tumor growth, inhibits MVD, down-regulates Flt-1 and KDR expression, and disturbs the stimulating effect of VEGF165 on the growth of SGC7901 cells. These results suggest that As2O3 might delay growth of gastric tumors through inhibiting the paracrine and autocrine pathways of VEGF/VEGFRs.

  15. Effects of vascularization on cancer nanochemotherapy outcomes

    Science.gov (United States)

    Paiva, L. R.; Ferreira, S. C.; Martins, M. L.

    2016-08-01

    Cancer therapy requires anticancer agents capable of efficient and uniform systemic delivery. One promising route to their development is nanotechnology. Here, a previous model for cancer chemotherapy based on a nanosized drug carrier (Paiva et al., 2011) is extended by including tissue vasculature and a three-dimensional growth. We study through computer simulations the therapy against tumors demanding either large or small nutrient supplies growing under different levels of tissue vascularization. Our results indicate that highly vascularized tumors demand more aggressive therapies (larger injected doses administrated at short intervals) than poorly vascularized ones. Furthermore, nanoparticle endocytic rate by tumor cells, not its selectivity, is the major factor that determines the therapeutic success. Finally, our finds indicate that therapies combining cytotoxic agents with antiangiogenic drugs that reduce the abnormal tumor vasculature, instead of angiogenic drugs that normalize it, can lead to successful treatments using feasible endocytic rates and administration intervals.

  16. Killing effect of coexpressing cytosine deaminase and thymidine kinase on rat vascular smooth muscle cells

    Institute of Scientific and Technical Information of China (English)

    曹慧青; 孟宪敏; 刘冬青; 赵秀文; 丁金凤

    2004-01-01

    Background Vascular smooth muscle cell (VSMC) proliferation following arterial injury plays a critical role in a variety of vascular proliferative disorders, such as atherosclerosis and restenosis after balloon angioplasty. Herpes simplex virus-thymidine kinase (HSV-TK)/ganciclovir (GCV) and E.coli cytosine deaminase (CD)/5-fluorocytosine (5-Fc) suicide gene systems have been successfully employed in cardiovascular gene therapy, respectively. We reasoned that coexpression of both HSV-TK with CD suicide genes would lead to increased cell killing. To test this imagine, the adenoviral vectors expressing TK and/or CD genes were developed and tested on vascular smooth muscle cells. Methods Adenoviral vectors, including Ad-EF1α-CD-cytomegolovirus (CMV)-TK coexpressing both CD and TK double suicide genes, Ad-EF1α-CD and Ad-CMV-TK expressing CD and TK respectively, and control vector Ad-CMV-LacZ, were constructed and prepared with homologous recombination in RecA+E.coli cells. Integration and expression of CD and/or TK gene were identified by PCR and Western blot. Primary cultured VSMCs were infected at a multiplicity of infection (MOI) of 20 with exposure to their matching prodrugs 5-Fc and GCV. Cell mortality was measured by methyl thiazolyl tetrazolium (MTT) assays. Flow cytometry analysis was used to detect cell death. Apoptotic cells were analyzed using Hoechst 33342 fluorescence dye as a DNA probe. Genomic DNA cleavage of apoptotic VSMCs was tested by agarose gel electrophoresis. Results Recombinant adenovirus expressing CD and/or TK suicide genes were successfully constructed. Both single and double suicide genes could be integrated into adenoviral genome and expressed. Cytotoxic effects of Ad-EF1α-CD-CMV-TK double suicide genes combined with 5-Fc and GCV were higher than those of Ad-CMV-TK and Ad-EF1α-CD single gene groups. The rate of cell survival was only (9±3)% in the Ad-EF1α-CD-CMV-TK group, but (37±3)% in the Ad-CMV-TK and (46±4)% in the Ad-EF1

  17. Genetic and epigenetic alterations of the reduced folate carrier in untreated diffuse large B-cell lymphoma

    DEFF Research Database (Denmark)

    Kastrup, I.B.; Worm, J.; Ralfkiaer, E.;

    2008-01-01

    The reduced folate carrier (RFC) is a transmembrane protein that mediates cellular uptake of reduced folates and antifolate drugs, including methotrexate (MTX). Acquired alterations of the RFC gene have been associated with resistance to MTX in cancer cell lines and primary osteosarcomas. Here, we...

  18. Genetic and epigenetic alterations of the reduced folate carrier in untreated diffuse large B-cell lymphoma

    DEFF Research Database (Denmark)

    Kastrup, Ingelise Bjerring; Worm, Jesper; Ralfkiaer, Elisabeth;

    2007-01-01

    The reduced folate carrier (RFC) is a transmembrane protein that mediates cellular uptake of reduced folates and antifolate drugs, including methotrexate (MTX). Acquired alterations of the RFC gene have been associated with resistance to MTX in cancer cell lines and primary osteosarcomas. Here, we...

  19. Loss of nuclear BRCA1 protein staining in normal tissue cells derived from BRCA1 and BRCA2 mutation carriers

    International Nuclear Information System (INIS)

    Enhanced genomic instability has been recently reported in normal cells derived from BRCA1/2 mutation carriers when placed in vitro in non-physiological stress conditions. We present here original data which help to explain the observed genomic instability. Leucocytes from BRCA1/2 mutation carriers, sporadic breast cancer patients and controls were prepared for BRCA1 immunocytochemistry. We show that BRCA1 containing nuclear dot like structures are detectable in about 80% of the leucocytes from controls and sporadic breast cancer patients, but are absent in the majority of normal cells from BRCA1 as well as BRCA2 mutation carriers (also in their normal breast cells). Our results thus indicate that the genomic instability observed in normal cells from BRCA1 and BRCA2 mutation carriers is associated with a down-regulation of nuclear BRCA1 protein accumulation in the dot like structures. These results suggest in addition that immunocytochemical or alternative molecular screening strategies might help to identify women with a high risk for breast (ovarian) cancer even when the underlying genetic defect remains undetectable

  20. Loss of nuclear BRCA1 protein staining in normal tissue cells derived from BRCA1 and BRCA2 mutation carriers

    Energy Technology Data Exchange (ETDEWEB)

    Brakeleer, Sylvia de [Laboratory of Molecular Oncology (Department of Medical Oncology), UZ Brussel, Vrije Universiteit Brussel, Laarbeeklaan 103, 1090 Brussels (Belgium); Bogdani, Marika [Department of Experimental Pathology, Vrije Universiteit Brussel, Laarbeeklaan 103, 1090 Brussels (Belgium); Greve, Jacques de [Laboratory of Molecular Oncology (Department of Medical Oncology), UZ Brussel, Vrije Universiteit Brussel, Laarbeeklaan 103, 1090 Brussels (Belgium); Familial Cancer Clinic, UZ Brussel, Laarbeeklaan 101, 1090 Brussels (Belgium); Decock, Julie [Laboratory of Molecular Oncology (Department of Medical Oncology), UZ Brussel, Vrije Universiteit Brussel, Laarbeeklaan 103, 1090 Brussels (Belgium); Sermijn, Erica [Familial Cancer Clinic, UZ Brussel, Laarbeeklaan 101, 1090 Brussels (Belgium); Bonduelle, Maryse [Familial Cancer Clinic, UZ Brussel, Laarbeeklaan 101, 1090 Brussels (Belgium); Goelen, Guido [Familial Cancer Clinic, UZ Brussel, Laarbeeklaan 101, 1090 Brussels (Belgium); Teugels, Erik [Laboratory of Molecular Oncology (Department of Medical Oncology), UZ Brussel, Vrije Universiteit Brussel, Laarbeeklaan 103, 1090 Brussels (Belgium) and Familial Cancer Clinic, UZ Brussel, Laarbeeklaan 101, 1090 Brussels (Belgium)]. E-mail: eteugels@uzbrussel.be

    2007-06-01

    Enhanced genomic instability has been recently reported in normal cells derived from BRCA1/2 mutation carriers when placed in vitro in non-physiological stress conditions. We present here original data which help to explain the observed genomic instability. Leucocytes from BRCA1/2 mutation carriers, sporadic breast cancer patients and controls were prepared for BRCA1 immunocytochemistry. We show that BRCA1 containing nuclear dot like structures are detectable in about 80% of the leucocytes from controls and sporadic breast cancer patients, but are absent in the majority of normal cells from BRCA1 as well as BRCA2 mutation carriers (also in their normal breast cells). Our results thus indicate that the genomic instability observed in normal cells from BRCA1 and BRCA2 mutation carriers is associated with a down-regulation of nuclear BRCA1 protein accumulation in the dot like structures. These results suggest in addition that immunocytochemical or alternative molecular screening strategies might help to identify women with a high risk for breast (ovarian) cancer even when the underlying genetic defect remains undetectable.

  1. Vascular Platform to Define Hematopoietic Stem Cell Factors and Enhance Regenerative Hematopoiesis

    Directory of Open Access Journals (Sweden)

    Michael G. Poulos

    2015-11-01

    Full Text Available Hematopoietic stem cells (HSCs inhabit distinct microenvironments within the adult bone marrow (BM, which govern the delicate balance between HSC quiescence, self-renewal, and differentiation. Previous reports have proposed that HSCs localize to the vascular niche, comprised of endothelium and tightly associated perivascular cells. Herein, we examine the capacity of BM endothelial cells (BMECs to support ex vivo and in vivo hematopoiesis. We demonstrate that AKT1-activated BMECs (BMEC-Akt1 have a unique transcription factor/cytokine profile that supports functional HSCs in lieu of complex serum and cytokine supplementation. Additionally, transplantation of BMEC-Akt1 cells enhanced regenerative hematopoiesis following myeloablative irradiation. These data demonstrate that BMEC-Akt1 cultures can be used as a platform for the discovery of pro-HSC factors and justify the utility of BMECs as a cellular therapy. This technical advance may lead to the development of therapies designed to decrease pancytopenias associated with myeloablative regimens used to treat a wide array of disease states.

  2. Inhibition of NF-κB activity in rabbit vascular smooth muscle cells by lovastatin

    International Nuclear Information System (INIS)

    Nuclear factor NF-κB is believed to play an important role in regulating the production of matrix metalloproteinase (MMPs), which induce atherosclerosis, restenosis and plaque rupture. We incubated rabbit vascular smooth muscle cells (RVSMCs) with 5 μmol/L lovastatin in the presence of IL-1-α and PDGFBB (20 μg/L, respectively) to study whether lovastatin inhibited NF-κB binding activity induced by IL-1 and PDGF. The NF-κB activity was detected by electrophoretic mobility shift assay (EMSA); MMP-1 and MMP-3 were measured by western blotting; and MMP-9 was detected by zymography. The result showed that lovastatin strongly reduced NF-κB activity upregulated by IL-1 combined with PDGF, and lovastatin also dose-dependently inhibited the expression of MMP-1, -3 and -9 induced by IL-1 and PDGF. It suggested that the beneficial effects of statins may extend to mechanisms beyond cholesterol reduction

  3. Analysis of Active Components in Salvia Miltiorrhiza Injection Based on Vascular Endothelial Cell Protection

    Directory of Open Access Journals (Sweden)

    Shen Jie

    2014-09-01

    Full Text Available Correlation analysis based on chromatograms and pharmacological activities is essential for understanding the effective components in complex herbal medicines. In this report, HPLC and measurement of antioxidant properties were used to describe the active ingredients of Salvia miltiorrhiza injection (SMI. HPLC results showed that tanshinol, protocatechuic aldehyde, rosmarinic acid, salvianolic acid B, protocatechuic acid and their metabolites in rat serum may contribute to the efficacy of SMI. Assessment of antioxidant properties indicated that differences in the composition of serum powder of SMI caused differences in vascular endothelial cell protection. When bivariate correlation was carried out it was found that salvianolic acid B, tanshinol and protocatechuic aldehyde were active components of SMI because they were correlated to antioxidant properties.

  4. An Egr-1-specific DNAzyme regulates Egr-1 and proliferating cell nuclear antigen expression in rat vascular smooth muscle cells

    Science.gov (United States)

    ZHANG, JUNBIAO; GUO, CHANGLEI; WANG, RAN; HUANG, LULI; LIANG, WANQIAN; LIU, RUNNAN; SUN, BING

    2013-01-01

    The aim of the present study was to transfect rat aortic smooth muscle cells with an early growth response factor-1 (Egr-1)-specific DNAzyme (ED5), to observe its effect on Egr-1 and proliferating cell nuclear antigen (PCNA) expression and to elucidate the mechanism of ED5-mediated inhibition of vascular smooth muscle cell (VSMC) proliferation. VSMCs in primary culture obtained by tissue block adhesion were identified by morphological observation and α smooth muscle actin (α-SM-actin) immunocytochemistry. The cells were then transfected with ED5 or scrambled ED5 (ED5SCR). The three groups of cells used in the present study were the control group, ED5 group and ED5SCR group. The expression levels of Egr-1 and PCNA protein were detected following transfection by analyzing and calculating the integral optical density value in each group. Primary culture of VSMCs and transfection of ED5 and ED5SCR were successfully accomplished. Following stimulation with 10% fetal calf serum, the Egr-1 protein was expressed most strongly at 1 h and demonstrated a declining trend over time; the expression of PCNA protein began at 4 h, peaked at 24 h and then demonstrated a slightly declining trend over time. Compared with the control group and the ED5SCR group, ED5 inhibited the expression of Egr-1 and PCNA (P<0.05). ED5 was able to inhibit the expression of Egr-1 and PCNA proteins in VSMCs to a certain extent and VSMC proliferation in vitro. DNAzyme gene therapy may be useful as a new method for treating vascular proliferative diseases, including atherosclerosis and restenosis. PMID:23737882

  5. TRPC1 transcript variants, inefficient nonsense-mediated decay and low up-frameshift-1 in vascular smooth muscle cells

    Directory of Open Access Journals (Sweden)

    Kumar Bhaskar

    2011-07-01

    Full Text Available Abstract Background Transient Receptor Potential Canonical 1 (TRPC1 is a widely-expressed mammalian cationic channel with functional effects that include stimulation of cardiovascular remodelling. The initial aim of this study was to investigate variation in TRPC1-encoding gene transcripts. Results Extensive TRPC1 transcript alternative splicing was observed, with exons 2, 3 and 5-9 frequently omitted, leading to variants containing premature termination codons. Consistent with the predicted sensitivity of such variants to nonsense-mediated decay (NMD the variants were increased by cycloheximide. However it was notable that control of the variants by NMD was prominent in human embryonic kidney 293 cells but not human vascular smooth muscle cells. The cellular difference was attributed in part to a critical protein in NMD, up-frameshift-1 (UPF1, which was found to have low abundance in the vascular cells. Rescue of UPF1 by expression of exogenous UPF1 was found to suppress vascular smooth muscle cell proliferation. Conclusions The data suggest: (i extensive NMD-sensitive transcripts of TRPC1; (ii inefficient clearance of aberrant transcripts and enhanced proliferation of vascular smooth muscle cells in part because of low UPF1 expression.

  6. Sliding Fibers: Slidable, Injectable, and Gel-like Electrospun Nanofibers as Versatile Cell Carriers.

    Science.gov (United States)

    Lee, Slgirim; Yun, Seokhwan; Park, Kook In; Jang, Jae-Hyung

    2016-03-22

    Designing biomaterial systems that can mimic fibrous, natural extracellular matrix is crucial for enhancing the efficacy of various therapeutic tools. Herein, a smart technology of three-dimensional electrospun fibers that can be injected in a minimally invasive manner was developed. Open surgery is currently the only route of administration of conventional electrospun fibers into the body. Coordinating electrospun fibers with a lubricating hydrogel produced fibrous constructs referred to as slidable, injectable, and gel-like (SLIDING) fibers. These SLIDING fibers could pass smoothly through a catheter and fill any cavity while maintaining their fibrous morphology. Their injectable features were derived from their distinctive rheological characteristics, which were presumably caused by the combinatorial effects of mobile electrospun fibers and lubricating hydrogels. The resulting injectable fibers fostered a highly favorable environment for human neural stem cell (hNSC) proliferation and neurosphere formation within the fibrous structures without compromising hNSC viability. SLIDING fibers demonstrated superior performance as cell carriers in animal stroke models subjected to the middle cerebral artery occlusion (MCAO) stroke model. In this model, SLIDING fiber application extended the survival rate of administered hNSCs by blocking microglial infiltration at the early, acute inflammatory stage. The development of SLIDING fibers will increase the clinical significance of fiber-based scaffolds in many biomedical fields and will broaden their applicability. PMID:26885937

  7. Nanostructured lipid carrier in photodynamic therapy for the treatment of basal-cell carcinoma.

    Science.gov (United States)

    Qidwai, Afreen; Khan, Saba; Md, Shadab; Fazil, Mohammad; Baboota, Sanjula; Narang, Jasjeet K; Ali, Javed

    2016-05-01

    Topical photodynamic therapy (PDT) is a promising alternative for malignant skin diseases such as basal-cell carcinoma (BCC), due to its simplicity, enhanced patient compliance, and localization of the residual photosensitivity to the site of application. However, insufficient photosensitizer penetration into the skin is the major issue of concern with topical PDT. Therefore, the aim of the present study was to enable penetration of photosensitizer to the different strata of the skin using a lipid nanocarrier system. We have attempted to develop a nanostructured lipid carrier (NLC) for the topical delivery of second-generation photosensitizer, 5-amino levulinic acid (5-ALA), whose hydrophilicity and charge characteristic limit its percutaneous absorption. The microemulsion technique was used for preparing 5-ALA-loaded NLC. The mean particle size, polydispersity index, and entrapment efficiency of the optimized NLC of 5-ALA were found to be 185.2 ± 1.20, 0.156 ± 0.02, and 76.8 ± 2.58%, respectively. The results of in vitro release and in vitro skin permeation studies showed controlled drug release and enhanced penetration into the skin, respectively. Confocal laser scanning microscopy and cell line studies respectively demonstrated that encapsulation of 5-ALA in NLC enhanced its ability to reach deeper skin layers and consequently, increased cytotoxicity. PMID:26978275

  8. Thermal influence on charge carrier transport in solar cells based on GaAs PN junctions

    Energy Technology Data Exchange (ETDEWEB)

    Osses-Márquez, Juan; Calderón-Muñoz, Williams R., E-mail: wicalder@ing.uchile.cl [Department of Mechanical Engineering, University of Chile, Beauchef 850, Santiago (Chile)

    2014-10-21

    The electron and hole one-dimensional transport in a solar cell based on a Gallium Arsenide (GaAs) PN junction and its dependency with electron and lattice temperatures are studied here. Electrons and heat transport are treated on an equal footing, and a cell operating at high temperatures using concentrators is considered. The equations of a two-temperature hydrodynamic model are written in terms of asymptotic expansions for the dependent variables with the electron Reynolds number as a perturbation parameter. The dependency of the electron and hole densities through the junction with the temperature is analyzed solving the steady-state model at low Reynolds numbers. Lattice temperature distribution throughout the device is obtained considering the change of kinetic energy of electrons due to interactions with the lattice and heat absorbed from sunlight. In terms of performance, higher values of power output are obtained with low lattice temperature and hot energy carriers. This modeling contributes to improve the design of heat exchange devices and thermal management strategies in photovoltaic technologies.

  9. Thermal influence on charge carrier transport in solar cells based on GaAs PN junctions

    International Nuclear Information System (INIS)

    The electron and hole one-dimensional transport in a solar cell based on a Gallium Arsenide (GaAs) PN junction and its dependency with electron and lattice temperatures are studied here. Electrons and heat transport are treated on an equal footing, and a cell operating at high temperatures using concentrators is considered. The equations of a two-temperature hydrodynamic model are written in terms of asymptotic expansions for the dependent variables with the electron Reynolds number as a perturbation parameter. The dependency of the electron and hole densities through the junction with the temperature is analyzed solving the steady-state model at low Reynolds numbers. Lattice temperature distribution throughout the device is obtained considering the change of kinetic energy of electrons due to interactions with the lattice and heat absorbed from sunlight. In terms of performance, higher values of power output are obtained with low lattice temperature and hot energy carriers. This modeling contributes to improve the design of heat exchange devices and thermal management strategies in photovoltaic technologies.

  10. Mechanical and Vascular Cues Synergistically Enhance Osteogenesis in Human Mesenchymal Stem Cells.

    Science.gov (United States)

    Steward, Andrew J; Cole, Jacqueline H; Ligler, Frances S; Loboa, Elizabeth G

    2016-08-01

    Development and maintenance of a vascular network are critical for bone growth and homeostasis; strategies that promote vascular function are critical for clinical success of tissue-engineered bone constructs. Co-culture of endothelial cells (ECs) with mesenchymal stem cells (MSCs) and exposure to 10% cyclic tensile strain have both been shown to regulate osteogenesis in isolation, but potential synergistic effects have yet to be explored. The objective of this study was to expose an MSC-EC co-culture to 10% cyclic tensile strain to examine the role of this mechanical stimulus on MSC-EC behavior. We hypothesized that paracrine signaling from ECs would stimulate osteogenesis of MSCs, and exposure to 10% cyclic tensile strain would enhance this anabolic signal. Human umbilical vein ECs and human bone marrow-derived MSCs were either monocultured or co-cultured at a 1:1 ratio in a mixed osteo/angiogenic medium, exposed to 10% cyclic tensile strain at 1 Hz for 4 h/day for 2 weeks, and biochemically and histologically analyzed for endothelial and osteogenic markers. While neither 10% cyclic tensile strain nor co-culture alone had a significant effect on osteogenesis, the concurrent application of strain to an MSC-EC co-culture resulted in a significant increase in calcium accretion and mineral deposition, suggesting that co-culture and strain synergistically enhance osteogenesis. Neither co-culture, 10% cyclic tensile strain, nor a combination of these stimuli affected endothelial markers, indicating that the endothelial phenotype remained stable, but unresponsive to the stimuli evaluated in this study. This study is the first to investigate the role of cyclic tensile strain on the complex interplay between ECs and MSCs in co-culture. The results of this study provide key insights into the synergistic effects of 10% cyclic tensile strain and co-culture on osteogenesis. Understanding mechanobiological factors affecting MSC-EC crosstalk will help enhance strategies for

  11. Schedule-Dependent Antiangiogenic and Cytotoxic Effects of Chemotherapy on Vascular Endothelial and Retinoblastoma Cells.

    Science.gov (United States)

    Winter, Ursula; Mena, Hebe A; Negrotto, Soledad; Arana, Eloisa; Pascual-Pasto, Guillem; Laurent, Viviana; Suñol, Mariona; Chantada, Guillermo L; Carcaboso, Angel M; Schaiquevich, Paula

    2016-01-01

    Current treatment of retinoblastoma involves using the maximum dose of chemotherapy that induces tumor control and is tolerated by patients. The impact of dose and schedule on the cytotoxicity of chemotherapy has not been studied. Our aim was to gain insight into the cytotoxic and antiangiogenic effect of the treatment scheme of chemotherapy used in retinoblastoma by means of different in vitro models and to evaluate potential effects on multi-drug resistance proteins. Two commercial and two patient-derived retinoblastoma cell types and two human vascular endothelial cell types were exposed to increasing concentrations of melphalan or topotecan in a conventional (single exposure) or metronomic (7-day continuous exposure) treatment scheme. The concentration of chemotherapy causing a 50% decrease in cell proliferation (IC50) was determined by MTT and induction of apoptosis was evaluated by flow cytometry. Expression of ABCB1, ABCG2 and ABCC1 after conventional or metronomic treatments was assessed by RT-qPCR. We also evaluated the in vivo response to conventional (0.6 mg/kg once a week for 2 weeks) and metronomic (5 days a week for 2 weeks) topotecan in a retinoblastoma xenograft model. Melphalan and topotecan were cytotoxic to both retinoblastoma and endothelial cells after conventional and metronomic treatments. A significant decrease in the IC50 (median, 13-fold; range: 3-23) was observed following metronomic chemotherapy treatment in retinoblastoma and endothelial cell types compared to conventional treatment (p0.05). In mice, continuous topotecan lead to significantly lower tumor volumes compared to conventional treatment after 14 days of treatment (pretinoblastoma and endothelial cells to both chemotherapy agents with lower IC50 values compared to short-term treatment. These findings were validated in an in vivo model. None of the dosing modalities induced multidrug resistance mechanisms while apoptosis was the mechanism of cell death after both treatment

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

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

    International Nuclear Information System (INIS)

    Highlights: ► Anti-atherogenic effect of PL was examined using partial carotid ligation model in ApoE KO mice. ► PL prevented atherosclerotic plaque development, VSMCs proliferation, and NF-κB activation. ► Piperlongumine reduced vascular smooth muscle cell activation through PDGF-Rβ and NF-κB-signaling. ► 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-κB) 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 Cγ1, extracellular signal-regulated kinases 1 and 2 and Akt. Lastly, PL significantly attenuated activation of NF-κB—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.

  14. Essential role of TGF-beta/Smad pathway on statin dependent vascular smooth muscle cell regulation.

    Directory of Open Access Journals (Sweden)

    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.

  15. Sustained diacylglycerol formation from inositol phospholipids in angiotensin II-stimulated vascular smooth muscle cells

    Energy Technology Data Exchange (ETDEWEB)

    Griendling, K.K.; Rittenhouse, S.E.; Brock, T.A.; Ekstein, L.S.; Gimbrone, M.A. Jr.; Alexander, R.W.

    1986-05-05

    Angiotensin II acts on cultured rat aortic vascular smooth muscle cells to stimulate phospholipase C-mediated hydrolysis of membrane phosphoinositides and subsequent formation of diacylglycerol and inositol phosphates. In intact cells, angiotensin II induces a dose-dependent increase in diglyceride which is detectable after 5 s and sustained for at least 20 min. Angiotensin II (100 nM)-stimulated diglyceride formation is biphasic, peaking at 15 s (227 +/- 19% control) and at 5 min (303 +/- 23% control). Simultaneous analysis of labeled inositol phospholipids shows that at 15 s phosphatidylinositol 4,5-bisphosphate (PIP2) and phosphatidylinositol 4-phosphate (PIP) decline to 52 +/- 6% control and 63 +/- 5% control, respectively, while phosphatidylinositol (PI) remains unchanged. In contrast, at 5 min, PIP2 and PIP have returned toward control levels (92 +/- 2 and 82 +/- 4% control, respectively), while PI has decreased substantially (81 +/- 2% control). The calcium ionophore ionomycin (15 microM) stimulates diglyceride accumulation but does not cause PI hydrolysis. 4 beta-Phorbol 12-myristate 13-acetate, an activator of protein kinase C, inhibits early PIP and PIP2 breakdown and diglyceride formation, without inhibiting late-phase diglyceride accumulation. Thus, angiotensin II induces rapid transient breakdown of PIP and PIP2 and delayed hydrolysis of PI. The rapid attenuation of polyphosphoinositide breakdown is likely caused by a protein kinase C-mediated inhibition of PIP and PIP2 hydrolysis. While in vascular smooth muscle stimulated with angiotensin II inositol 1,4,5-trisphosphate formation is transient, diglyceride production is biphasic, suggesting that initial and sustained diglyceride formation from the phosphoinositides results from different biochemical and/or cellular processes.

  16. Inducing effects of hepatocyte growth factor on the expression of vascular endothelial growth factor in human colorectal carcinoma cells through MEK and PI3K signaling pathways

    Institute of Scientific and Technical Information of China (English)

    ZHANG Yu-hua; WEI Wei; XU Hao; WANG Yan-yan; WU Wen-xi

    2007-01-01

    Background Vascular endothelial growth factor plays a key role in human colorectal carcinoma invasion and metastasis. However, the regulation mechanism remains unknown. Recent studies have shown that several cytokines can regulate the expression of vascular endothelial growth factor in tumor cells. In this study, we investigated whether hepatocyte growth factor can regulate the expression of vascular endothelial growth factor in colorectal carcinoma cells.Methods Hepatocyte growth factor and vascular endothelial growth factor in human serum were measured by ELISA.The mRNA level of vascular endothelial growth factor was analyzed by reverse transcription-PCR. Western blot assay was performed to evaluate levels of c-Met and several other proteins involved in the MAPK and PI3K signaling pathways in colorectal carcinoma cells.Results Serum hepatocyte growth factor and vascular endothelial growth factor were significantly increased in colorectal carcinoma subjects. In vitro extraneous hepatocyte growth factor markedly increased protein and mRNA levels of vascular endothelial growth factor in colorectal carcinoma cells. Hepatocyte growth factor induced phosphorylation of c-Met, ERK1/2 and AKT in a dose-dependent manner. Specific inhibitors on MEK and PI3K inhibited the hepatocyte growth factor-induced expression of vascular endothelial growth factor in colorectal carcinoma cells.Conclusion This present study indicates that hepatocyte growth factor upregulates the expression of vascular endothelial growth factor in colorectal carcinoma cells via the MEK/ERK and PI3K/AKT signaling pathways.

  17. By Different Cellular Mechanisms, Lymphatic Vessels Sprout by Endothelial Cell Recruitment Whereas Blood Vessels Grow by Vascular Expansion

    Science.gov (United States)

    Parsons-Wingerter, Patricia; McKay, Terri L.; Leontiev, Dmitry; Condrich, Terence K.; DiCorleto, Paul E.

    2005-01-01

    The development of effective vascular therapies requires the understanding of all modes of vessel formation contributing to vasculogenesis, angiogenesis (here termed hemangiogenesis) and lymphangiogenesis. We show that lymphangiogenesis proceeds by blind-ended vessel sprouting via recruitment of isolated endothelial progenitor cells to the tips of growing vessels, whereas hemangiogenesis occurs by non-sprouting vessel expansion from the capillary network, during middevelopment in the quail chorioallantoic membrane (CAM). Blood vessels expanded out of capillaries that displayed transient expression of alpha smooth muscle actin (alphaSMA), accompanied by mural recruitment of migratory progenitor cells expressing SMA. Lymphatics and blood vessels were identified by confocal/fluorescence microscopy of vascular endothelial growth factor (VEGF) receptors VEGFR-1 and VEGFR-2, alphaSMA (expressed on CAM blood vessels but not on lymphatics), homeobox transcription factor Prox-1 (specific to CAM lymphatic endothelium), and the quail hematopoetic/vascular marker, QH-1. Expression of VEGFR-1 was highly restricted to blood vessels (primarily capillaries). VEGFR-2 was expressed intensely in isolated hematopoietic cells, lymphatic vessels and moderately in blood vessels. Prox-1 was absent from endothelial progenitor cells prior to lymphatic recruitment. Although vascular endothelial growth factor-165 (VEGF(sub 165)) is a key regulator of numerous cellular processes in hemangiogenesis and vasculogenesis, the role of VEGF(sub 165) in lymphangiogenesis is less clear. Exogenous VEGF(sub 165) increased blood vessel density without changing endogenous modes of vascular/lymphatic vessel formation or marker expression patterns. However, VEGF(sub 165) did increase the frequency of blood vascular anastomoses and strongly induced the antimaturational dissociation of lymphatics from blood vessels, with frequent formation of homogeneous lymphatic networks.

  18. Conditional deletion of Dicer in vascular smooth muscle cells leads to the developmental delay and embryonic mortality

    Energy Technology Data Exchange (ETDEWEB)

    Pan, Yaoqian [Department of Physiology, University of Tennessee Health Science Center, Memphis, TN 38163 (United States); Center for Cancer Research, University of Tennessee Health Science Center, Memphis, TN 38163 (United States); Balazs, Louisa [Department of Pathology, University of Tennessee Health Science Center, Memphis, TN 38163 (United States); Tigyi, Gabor [Department of Physiology, University of Tennessee Health Science Center, Memphis, TN 38163 (United States); Yue, Junming, E-mail: yue@uthsc.edu [Department of Physiology, University of Tennessee Health Science Center, Memphis, TN 38163 (United States); Center for Cancer Research, University of Tennessee Health Science Center, Memphis, TN 38163 (United States)

    2011-05-13

    Highlights: {yields} Deletion of Dicer in vascular smooth muscle cells(VSMCs) leads to embryonic mortality. {yields} Loss of Dicer in VSMCs leads to developmental delay. {yields} Loss of Dicer in VSMCs leads to hemorrhage in various organs including brain, skin and liver. {yields} Loss of Dicer in VSMCs leads to vascular wall remodeling. {yields} Loss of Dicer in VSMCs dysregulates the expression of miRNA and VSMC marker genes. -- Abstract: Dicer is a RNAase III enzyme that cleaves double stranded RNA and generates small interfering RNA (siRNA) and microRNA (miRNA). The goal of this study is to examine the role of Dicer and miRNAs in vascular smooth muscle cells (VSMCs). We deleted Dicer in VSMCs of mice, which caused a developmental delay that manifested as early as embryonic day E12.5, leading to embryonic death between E14.5 and E15.5 due to extensive hemorrhage in the liver, brain, and skin. Dicer KO embryos showed dilated blood vessels and a disarray of vascular architecture between E14.5 and E15.5. VSMC proliferation was significantly inhibited in Dicer KOs. The expression of VSMC marker genes were significantly downregulated in Dicer cKO embryos. The vascular structure of the yolk sac and embryo in Dicer KOs was lost to an extent that no blood vessels could be identified after E15.5. Expression of most miRNAs examined was compromised in VSMCs of Dicer KO. Our results indicate that Dicer is required for vascular development and regulates vascular remodeling by modulating VSMC proliferation and differentiation.

  19. Conditional deletion of Dicer in vascular smooth muscle cells leads to the developmental delay and embryonic mortality

    International Nuclear Information System (INIS)

    Highlights: → Deletion of Dicer in vascular smooth muscle cells(VSMCs) leads to embryonic mortality. → Loss of Dicer in VSMCs leads to developmental delay. → Loss of Dicer in VSMCs leads to hemorrhage in various organs including brain, skin and liver. → Loss of Dicer in VSMCs leads to vascular wall remodeling. → Loss of Dicer in VSMCs dysregulates the expression of miRNA and VSMC marker genes. -- Abstract: Dicer is a RNAase III enzyme that cleaves double stranded RNA and generates small interfering RNA (siRNA) and microRNA (miRNA). The goal of this study is to examine the role of Dicer and miRNAs in vascular smooth muscle cells (VSMCs). We deleted Dicer in VSMCs of mice, which caused a developmental delay that manifested as early as embryonic day E12.5, leading to embryonic death between E14.5 and E15.5 due to extensive hemorrhage in the liver, brain, and skin. Dicer KO embryos showed dilated blood vessels and a disarray of vascular architecture between E14.5 and E15.5. VSMC proliferation was significantly inhibited in Dicer KOs. The expression of VSMC marker genes were significantly downregulated in Dicer cKO embryos. The vascular structure of the yolk sac and embryo in Dicer KOs was lost to an extent that no blood vessels could be identified after E15.5. Expression of most miRNAs examined was compromised in VSMCs of Dicer KO. Our results indicate that Dicer is required for vascular development and regulates vascular remodeling by modulating VSMC proliferation and differentiation.

  20. Surface Modified Biodegradable Electrospun Membranes as a Carrier for Human Embryonic Stem Cell-Derived Retinal Pigment Epithelial Cells.

    Science.gov (United States)

    Sorkio, Anni; Porter, Patrick J; Juuti-Uusitalo, Kati; Meenan, Brian J; Skottman, Heli; Burke, George A

    2015-09-01

    Human embryonic stem cell-derived retinal pigment epithelial (hESC-RPE) cells are currently undergoing clinical trials to treat retinal degenerative diseases. Transplantation of hESC-RPE cells in conjuction with a supportive biomaterial carrier holds great potential as a future treatment for retinal degeneration. However, there has been no such biodegradable material that could support the growth and maturation of hESC-RPE cells so far. The primary aim of this work was to create a thin porous poly (L-lactide-co-caprolactone) (PLCL) membrane that could promote attachment, proliferation, and maturation of the hESC-RPE cells in serum-free culture conditions. The PLCL membranes were modified by atmospheric pressure plasma processing and coated with collagen IV to enhance cell growth and maturation. Permeability of the membranes was analyzed with an Ussing chamber system. Analysis with scanning electron microscopy, contact angle measurement, atomic force microscopy, and X-ray photoelectron spectroscopy demonstrated that plasma surface treatment augments the surface properties of the membrane, which enhances the binding and conformation of the protein. Cell proliferation assays, reverse transcription-polymerase chain reaction, indirect immunofluoresence staining, trans-epithelial electrical resistance measurements, and in vitro phagocytosis assay clearly demonstrated that the plasma treated PLCL membranes supported the adherence, proliferation, maturation and functionality of hESC-RPE cells in serum-free culture conditions. Here, we report for the first time, how PLCL membranes can be modified with atmospheric pressure plasma processing to enable the formation of a functional hESC-RPE monolayer on a porous biodegradable substrate, which have a potential as a tissue-engineered construct for regenerative retinal repair applications. PMID:25946229

  1. Regional and Stage-Specific Effects of Prospectively Purified Vascular Cells on the Adult V-SVZ Neural Stem Cell Lineage

    OpenAIRE

    Crouch, Elizabeth E.; Liu, Chang; Silva-Vargas, Violeta; Doetsch, Fiona

    2015-01-01

    Adult neural stem cells reside in specialized niches. In the ventricular-subventricular zone (V-SVZ), quiescent neural stem cells (qNSCs) become activated (aNSCs), and generate transit amplifying cells (TACs), which give rise to neuroblasts that migrate to the olfactory bulb. The vasculature is an important component of the adult neural stem cell niche, but whether vascular cells in neurogenic areas are intrinsically different from those elsewhere in the brain is unknown. Moreover, the contri...

  2. 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.

  3. Isolation of cell nuclei in microchannels by short-term chemical treatment via two-step carrier medium exchange.

    Science.gov (United States)

    Toyama, Kaori; Yamada, Masumi; Seki, Minoru

    2012-08-01

    Separation/purification of nuclei from cells is a critical process required for medical and biochemical research applications. Here, we report a flow-through microfluidic device for isolating cell nuclei by selectively digesting the cell membrane by using the concept of hydrodynamic filtration (HDF). When a cell suspension is continuously introduced into a microchannel (main channel) possessing multiple side channels, cells flow through the main channel, whereas the carrier medium of the cells is drained through the side channels. Introductions of a cell treatment solution containing a surfactant and a washing buffer enable the two-step exchange of the carrier-medium and the cell treatment by the surfactant for a short span of time. The precise control of the treatment time by changing the flow rate and/or the size of the microchannel enables the selective digestion of cell membranes, resulting in the isolation of cell nuclei after separation from membrane debris and cytoplasmic components according to size. We examined several surfactant molecules and demonstrated that Triton X-100 exhibited high efficiency regarding nucleus isolation for both adherent (HeLa) and nonadherent (JM) cells, with a recovery ratio of ~80 %. In addition, the isolation efficiency was evaluated by western blotting. The presented flow-through microfluidic cell-nucleus separator may be a useful tool for general biological applications, because of its simplicity in operation, high reproducibility, and accuracy. PMID:22544390

  4. Asthma is a risk factor for acute chest syndrome and cerebral vascular accidents in children with sickle cell disease

    Directory of Open Access Journals (Sweden)

    Scott Paul J

    2005-01-01

    Full Text Available Abstract Background Asthma and sickle cell disease are common conditions that both may result in pulmonary complications. We hypothesized that children with sickle cell disease with concomitant asthma have an increased incidence of vaso-occlusive crises that are complicated by episodes of acute chest syndrome. Methods A 5-year retrospective chart analysis was performed investigating 48 children ages 3–18 years with asthma and sickle cell disease and 48 children with sickle cell disease alone. Children were matched for age, gender, and type of sickle cell defect. Hospital admissions were recorded for acute chest syndrome, cerebral vascular accident, vaso-occlusive pain crises, and blood transfusions (total, exchange and chronic. Mann-Whitney test and Chi square analysis were used to assess differences between the groups. Results Children with sickle cell disease and asthma had significantly more episodes of acute chest syndrome (p = 0.03 and cerebral vascular accidents (p = 0.05 compared to children with sickle cell disease without asthma. As expected, these children received more total blood transfusions (p = 0.01 and chronic transfusions (p = 0.04. Admissions for vasoocclusive pain crises and exchange transfusions were not statistically different between cases and controls. SS disease is more severe than SC disease. Conclusions Children with concomitant asthma and sickle cell disease have increased episodes of acute chest syndrome, cerebral vascular accidents and the need for blood transfusions. Whether aggressive asthma therapy can reduce these complications in this subset of children is unknown and requires further studies.

  5. Glial cell line-derived neurotrophic factor gene delivery via a polyethylene imine grafted chitosan carrier

    Directory of Open Access Journals (Sweden)

    Peng YS

    2014-06-01

    Full Text Available Yu-Shiang Peng,1,* Po-Liang Lai,2,* Sydney Peng,1 His-Chin Wu,3 Siang Yu,1 Tsan-Yun Tseng,4 Li-Fang Wang,5 I-Ming Chu1 1Department of Chemical Engineering, National Tsing Hua University, Hsinchu, 2Department of Orthopedic Surgery, Chang Gung Memorial Hospital at Linkou, Chang Gung University College of Medicine, Taoyuan, 3Department of Materials Engineering, Tatung University, Taipei, 4Graduate School of Biotechnology and Bioengineering, College of Engineering, Yuan Ze University, Chung-Li, 5Department of Medicinal and Applied Chemistry, Kaohsiung Medical University, Kaohsiung, Taiwan *Yu-Shiang Peng and Po-Liang Lai contributed equally to this work Abstract: Parkinson’s disease is known to result from the loss of dopaminergic neurons. Direct intracerebral injections of high doses of recombinant glial cell line-derived neurotrophic factor (GDNF have been shown to protect adult nigral dopaminergic neurons. Because GDNF does not cross the blood–brain barrier, intracerebral gene transfer is an ideal option. Chitosan (CHI is a naturally derived material that has been used for gene transfer. However, the low water solubility often leads to decreased transfection efficiency. Grafting of highly water-soluble polyethylene imines (PEI and polyethylene glycol onto polymers can increase their solubility. The purpose of this study was to design a non-viral gene carrier with improved water solubility as well as enhanced transfection efficiency for treating Parkinsonism. Two molecular weights (Mw =600 and 1,800 g/mol of PEI were grafted onto CHI (PEI600-g-CHI and PEI1800-g-CHI, respectively by opening the epoxide ring of ethylene glycol diglycidyl ether (EX-810. This modification resulted in a non-viral gene carrier with less cytotoxicity. The transfection efficiency of PEI600-g-CHI/deoxyribonucleic acid (DNA polyplexes was significantly higher than either PEI1800-g-CHI/DNA or CHI/DNA polyplexes. The maximal GDNF expression of PEI600-g-CHI/DNA was at the

  6. Effect of L-Arginine on Pulmonary Artery Smooth Muscle Cell Apoptosis in Rats with Hypoxic Pulmonary Vascular Structural Remodeling

    Institute of Scientific and Technical Information of China (English)

    Ingrid Karmane SUMOU; Jun-Bao DU; Bing WEI; Chun-Yu ZHANG; Jian-Guang QI; Chao-Shu TANG

    2006-01-01

    This study investigated the effect of L-arginine (L-Arg) on the apoptosis of pulmonary artery smooth muscle cells (PASMC) in rats with hypoxic pulmonary vascular structural remodeling, and its mechanisms. Seventeen Wistar rats were randomly divided into a control group (n=5), a hypoxia group (n=7), and a hypoxia+L-Arg group (n=5). The morphologic changes of lung tissues were observed under optical microscope. Using the terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphatebiotin nick end labeling assay, the apoptosis of PASMC was examined. Fas expression in PASMC was examined using immunohistochemistry. The results showed that the percentage of muscularized artery in small pulmonary vessels, and the relative medial thickness and relative medial area of the small and median pulmonary muscularized arteries in the hypoxic group were all significantly increased. Pulmonary vascular structural remodeling developed after hypoxia. Apoptotic smooth muscle cells of the small and median pulmonary arteries in the hypoxia group were significantly less than those in the control group. After 14 d of hypoxia, Fas expression by smooth muscle cells of median and small pulmonary arteries was significantly inhibited. L-Arg significantly inhibited hypoxic pulmonary vascular structural remodeling in association with an augmentation of apoptosis of smooth muscle cells as well as Fas expression in PASMC. These results showed that L-Arg could play an important role in attenuating hypoxic pulmonary vascular structural remodeling by upregulating Fas expression in PASMC, thus promoting the apoptosis of PASMC.

  7. Boosting angiogenesis and functional vascularization in injectable dextran-hyaluronic acid hydrogels by endothelial-like mesenchymal stromal cells

    NARCIS (Netherlands)

    Portalska, K.K.; Moreira Teixeira, L.S.; Leijten, J.C.H.; Jin, R.; Blitterswijk, van C.A.; Boer, de J.; Karperien, H.B.J.

    2014-01-01

    Angiogenesis and neo-vascularization are fundamental for the success of clinically relevant- sized tissue engineered (TE) constructs. The next generation of TE constructs relies on providing instructive materials combined with the delivery of angiogenic growth factors and cells to avoid tissue ische

  8. Adhesion, Growth, and Maturation of Vascular Smooth Muscle Cells on Low-Density Polyethylene Grafted with Bioactive Substances

    Czech Academy of Sciences Publication Activity Database

    Pařízek, Martin; Kasálková-Slepičková, N.; Bačáková, Lucie; Švindrych, Zdeněk; Slepička, P.; Bačáková, Markéta; Lisá, Věra; Švorčík, V.

    2013-01-01

    Roč. 2013, č. 2013 (2013), s. 371430. ISSN 2314-6133 R&D Projects: GA ČR(CZ) GBP108/12/G108 Institutional support: RVO:67985823 Keywords : biotechnology * tissue replacements * vascular smooth muscle cells * adhesion * modification Subject RIV: JJ - Other Materials

  9. Bacteria-induced release of white cell--and platelet-derived vascular endothelial growth factor in vitro

    DEFF Research Database (Denmark)

    Nielsen, Hans Jørgen; Werther, K; Mynster, T;

    2001-01-01

    BACKGROUND AND OBJECTIVES: Poor prognosis after resection of primary colorectal cancer may be related to the combination of perioperative blood transfusion and subsequent development of infectious complications. White blood cell--and platelet-derived cancer growth substances, including vascular e...

  10. Differential Cellular and Molecular Effects of Butyrate and Trichostatin A on Vascular Smooth Muscle Cells

    Directory of Open Access Journals (Sweden)

    Kasturi Ranganna

    2012-09-01

    Full Text Available The histone deacetylase (HDAC inhibitors, butyrate and trichostatin A (TSA, are epigenetic histone modifiers and proliferation inhibitors by downregulating cyclin D1, a positive cell cycle regulator, and upregulating p21Cip1 and INK family of proteins, negative cell cycle regulators. Our recent study indicated cyclin D1 upregulation in vascular smooth muscle cells (VSMC that are proliferation-arrested by butyrate. Here we investigate whether cyclin D1 upregulation is a unique response of VSMC to butyrate or a general response to HDAC inhibitors (HDACi by evaluating the effects of butyrate and TSA on VSMC. While butyrate and TSA inhibit VSMC proliferation via cytostatic and cytotoxic effects, respectively, they downregulate cdk4, cdk6, and cdk2, and upregulate cyclin D3, p21Cip1 and p15INK4B, and cause similar effects on key histone H3 posttranslational modifications. Conversely, cyclin D1 is upregulated by butyrate and inhibited by TSA. Assessment of glycogen synthase 3-dependent phosphorylation, subcellular localization and transcription of cyclin D1 indicates that differential effects of butyrate and TSA on cyclin D1 levels are linked to disparity in cyclin D1 gene expression. Disparity in butyrate- and TSA-induced cyclin D1 may influence transcriptional regulation of genes that are associated with changes in cellular morphology/cellular effects that these HDACi confer on VSMC, as a transcriptional modulator.

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

    Science.gov (United States)

    Zhao, Jingshan; Niu, Honglin; Li, Aiying; Nie, Lei

    2016-01-01

    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. PMID:26863518

  12. Modification of decellularized vascular scaffold with conditioned medium to enhance cell reseeding.

    Science.gov (United States)

    Zhao, Liang; Chen, Hong-Li; Xie, Li-Qin; Wang, Mian; Li, Xia-Fei; Feng, Zhi-Wei; Li, Min

    2016-08-01

    Repopulation of decellularized vascular scaffolds (DVS) is limited because of change in the repertoire and ratios of the remaining extracellular matrix (ECM) proteins, for example, loss of glycoproteins and the retention of type I collagen. Pre-treatment of DVS with defined ECM proteins, which match the repertoire of integrin receptors expressed by the embryonic stem cells (mESCs) to be seeded, can increase the reseeding efficacy. mESCs mainly express high levels of functional receptors for LM and FN. Reseeding efficiency of DVS with mESCs was very low, but was sigficantly increased (2.5 ± 0.1 fold) by pre-treating the DVS with A549-conditioned media. In addition, pre-treatment with A549-conditioned media led to a more homogeneous distribution of the seeded mESCs throughout the engineered blood vessel as compared to untreated DVS. This paper may promote blood vessel engineering by stressing the importance of matching the cell binding motifs of DVS and the integrin receptor repertoire of seeded cells. PMID:27193380

  13. Improved endothelialization of titanium vascular implants by extracellular matrix secreted from endothelial cells.

    Science.gov (United States)

    Tu, Qiufen; Zhao, Yuancong; Xue, Xiaoqing; Wang, Jin; Huang, Nan

    2010-12-01

    A variety of metals have been widely used in construction of cardiovascular implants (CVIs), such as artificial heart valves, ventricular pumps, and vascular stents. Although great effects have been put into rigorous anticoagulation, late thrombosis still occurred due to inferior blood and cell compatibility. Natural endothelium is popularly regarded as the only substance that has long-term anticoagulant ability. So, establishment of a compact endothelial cell (EC) monolayer on CVIs surface is a guarantee for their long-term potency. In the work described here, titanium (Ti) disks were coated with extracellular matrix (ECM) directly secreted by human umbilical vein endothelial cells (HUVECs), so as to help ECs proliferate and migrate and to improve their endothelialization in vivo. Deposition of ECM on Ti disks was detected by immunofluorescence microscopy, diffuse reflectance Fourier transform infrared spectroscopy, scanning electron microscopy, and atomic force microscopy. The surface topography and wettability of the Ti disks significantly changed after ECM deposition. Most importantly, it was found that ECM deposition inhibited platelet adhesion, stimulated EC proliferation, increased EC migration speed in vitro, and eventually accelerated the re-cellularization speed of Ti disks in vivo. These important results render it reasonable and feasible to modify CVIs with ECM secreted from ECs for improving their long-term potency. PMID:20666613

  14. Influence of optical interference and carrier lifetime on the short circuit current density of organic bulk heterojunction solar cells

    Institute of Scientific and Technical Information of China (English)

    You Hai-Long; Zhang Chun-Fu

    2009-01-01

    Based on simple analytical equations, short circuit current density (Jsc) of the organic bulk heterojunction solar cells has been calculated. It is found that the optical interference effect plays a very important role in the determination of JSC;and obvious oscillatory behaviour of Jsc was observed as a function of thickness. At the same time, the influence of JSC only increases the carrier lifetime on JSC also cannot be neglected. When the carrier lifetime is relatively short, at the initial stage and then decreases rapidly with the increase of active layer thickness. However, for a relatively long carrier lifetime, the exciton dissociation probability must be considered, and Jsc behaves wave-like with the increase of active layer thickness. The validity of this model is confirmed by the experimental results.

  15. Revealing the ultrafast charge carrier dynamics in organo metal halide perovskite solar cell materials using time resolved THz spectroscopy

    Science.gov (United States)

    Ponseca, C. S., Jr.; Sundström, V.

    2016-03-01

    Ultrafast charge carrier dynamics in organo metal halide perovskite has been probed using time resolved terahertz (THz) spectroscopy (TRTS). Current literature on its early time characteristics is unanimous: sub-ps charge carrier generation, highly mobile charges and very slow recombination rationalizing the exceptionally high power conversion efficiency for a solution processed solar cell material. Electron injection from MAPbI3 to nanoparticles (NP) of TiO2 is found to be sub-ps while Al2O3 NPs do not alter charge dynamics. Charge transfer to organic electrodes, Spiro-OMeTAD and PCBM, is sub-ps and few hundreds of ps respectively, which is influenced by the alignment of energy bands. It is surmised that minimizing defects/trap states is key in optimizing charge carrier extraction from these materials.

  16. Three-dimensional cell-dense constructs containing endothelial cell-networks are an effective tool for in vivo and in vitro vascular biology research.

    Science.gov (United States)

    Sekiya, Sachiko; Muraoka, Megumi; Sasagawa, Tadashi; Shimizu, Tatsuya; Yamato, Masayuki; Okano, Teruo

    2010-12-01

    Angiogenesis is a complicated natural process, and understanding the mechanism by which it occurs is important for medical, pharmaceutical, and cell biological sciences. Many techniques for investigating angiogenesis have been reported. In this study, we introduced a novel application of a cell culture technique that can be used in in vitro and in vivo vascular biology research. Cultivated endothelial cells (ECs) were harvested from temperature responsive culture dishes by reducing the temperature, without the need for a proteinase treatment. For this technique, the direct contact of ECs with fibroblasts was important for the formation of a capillary-like network in vitro. Moreover, layered cell sheets containing EC-networks produced lumen and vascular structures in the three-dimensional constructs, as well as in the construct transplanted into a living body. Thus, our culture technique was able to create cell sheets and three-dimensional constructs containing EC-networks, because they preserved normal and intrinsic cell-cell direct contact and various cell adhesive factors. Moreover, the thickness of these three-dimensional (3-D) constructs could be controlled by the number of layered cell sheets. These observations indicated that our novel technology contributed to the progress of vascular biology and lead to a new tool that can be used in in vivo and in vitro vascular biology research. PMID:20696176

  17. Verapamil stereoisomers induce antiproliferative effects in vascular smooth muscle cells via autophagy

    Energy Technology Data Exchange (ETDEWEB)

    Salabei, Joshua K. [Diabetes and Obesity Center, University of Louisville, Louisville, KY 40202 (United States); Department of Biochemistry and Molecular Biology, University of Louisville, Louisville, KY 40202 (United States); Balakumaran, Arun [Department of Pathology, University of Texas Medical Branch, Galveston, TX 77555‐0438 (United States); Frey, Justin C. [Department of Biology, University of Wisconsin-Eau Claire, Eau Claire, WI 54702 (United States); Boor, Paul J. [Department of Pathology, University of Texas Medical Branch, Galveston, TX 77555‐0438 (United States); Treinen-Moslen, Mary [Department of Internal Medicine, University of Texas Medical Branch, Galveston, TX 77555‐0609 (United States); Department of Pathology, University of Texas Medical Branch, Galveston, TX 77555‐0438 (United States); Conklin, Daniel J., E-mail: dj.conklin@louisville.edu [Diabetes and Obesity Center, University of Louisville, Louisville, KY 40202 (United States); Division of Cardiovascular Medicine, University of Louisville, Louisville, KY 40202 (United States); Department of Biology, University of Wisconsin-Eau Claire, Eau Claire, WI 54702 (United States); Department of Pathology, University of Texas Medical Branch, Galveston, TX 77555‐0438 (United States)

    2012-08-01

    Calcium channel blockers (CCBs) are important in the management of hypertension and limit restenosis. Although CCB efficacy could derive from decreased blood pressure, other mechanisms independent of CCB activity also can contribute to antiproliferative action. To understand mechanisms of CCB-mediated antiproliferation, we studied two structurally dissimilar CCBs, diltiazem and verapamil, in cultured rat vascular smooth muscle cells (VSMC). To elucidate CCB-independent effects, pure stereoisomers of verapamil (R-verapamil, inactive VR; S-verapamil, active, VS) were used. The effects of CCB exposure on cell viability (MTT reduction), cell proliferation ({sup 3}H-thymidine incorporation), VSMC morphology by light and transmission electron microscopy (TEM) and autophagy (LC3I/II, ATG5) were measured. In general, verapamil, VR or VS treatment alone (80 μM) appreciably enhanced MTT absorbance although higher concentrations (VR or VS) slightly decreased MTT absorbance. Diltiazem (140 μM) markedly decreased MTT absorbance (40%) at 120 h. VR or VS treatment inhibited {sup 3}H-thymidine incorporation (24 h) and induced cytological alterations (i.e., karyokinesis, enhanced perinuclear MTT deposition, accumulated perinuclear “vacuoles”). TEM revealed perinuclear “vacuoles” to be aggregates of highly laminated and electron-dense vesicles resembling autophagosomes and lysosomes, respectively. Increased autophagosome activity was confirmed by a concentration-dependent increase in LC3-II formation by Western blotting and by increased perinuclear LC3-GFP{sup +} puncta in verapamil-treated VSMC. Verapamil stereoisomers appeared to decrease perinuclear mitochondrial density. These observations indicate that antiproliferative effects of verapamil stereoisomers are produced by enhanced mitochondrial damage and upregulated autophagy in VSMC. These effects are independent of CCB activity indicating a distinct mechanism of action that could be targeted for more efficacious anti

  18. Verapamil stereoisomers induce antiproliferative effects in vascular smooth muscle cells via autophagy

    International Nuclear Information System (INIS)

    Calcium channel blockers (CCBs) are important in the management of hypertension and limit restenosis. Although CCB efficacy could derive from decreased blood pressure, other mechanisms independent of CCB activity also can contribute to antiproliferative action. To understand mechanisms of CCB-mediated antiproliferation, we studied two structurally dissimilar CCBs, diltiazem and verapamil, in cultured rat vascular smooth muscle cells (VSMC). To elucidate CCB-independent effects, pure stereoisomers of verapamil (R-verapamil, inactive VR; S-verapamil, active, VS) were used. The effects of CCB exposure on cell viability (MTT reduction), cell proliferation (3H-thymidine incorporation), VSMC morphology by light and transmission electron microscopy (TEM) and autophagy (LC3I/II, ATG5) were measured. In general, verapamil, VR or VS treatment alone (80 μM) appreciably enhanced MTT absorbance although higher concentrations (VR or VS) slightly decreased MTT absorbance. Diltiazem (140 μM) markedly decreased MTT absorbance (40%) at 120 h. VR or VS treatment inhibited 3H-thymidine incorporation (24 h) and induced cytological alterations (i.e., karyokinesis, enhanced perinuclear MTT deposition, accumulated perinuclear “vacuoles”). TEM revealed perinuclear “vacuoles” to be aggregates of highly laminated and electron-dense vesicles resembling autophagosomes and lysosomes, respectively. Increased autophagosome activity was confirmed by a concentration-dependent increase in LC3-II formation by Western blotting and by increased perinuclear LC3-GFP+ puncta in verapamil-treated VSMC. Verapamil stereoisomers appeared to decrease perinuclear mitochondrial density. These observations indicate that antiproliferative effects of verapamil stereoisomers are produced by enhanced mitochondrial damage and upregulated autophagy in VSMC. These effects are independent of CCB activity indicating a distinct mechanism of action that could be targeted for more efficacious anti

  19. Hypoxia and the Presence of Human Vascular Endothelial Cells Affect Prostate Cancer Cell Invasion and Metabolism

    Directory of Open Access Journals (Sweden)

    Ellen Ackerstaff

    2007-12-01

    Full Text Available Tumor progression and metastasis are influenced by hypoxia, as well as by interactions between cancer cells and components of the stroma, such as endothelial cells. Here, we have used a magnetic resonance (MRcompatible invasion assay to further understand the effects of hypoxia on human prostate cancer cell invasion and metabolism in the presence and absence of human umbilical vein endothelial cells (HUVECs. Additionally, we compared endogenous activities of selected proteases related to invasion in PC-3 cells and HUVECs, profiled gene expression of PC-3 cells by microarray, evaluated cell proliferation of PC-3 cells and HUVECs by flow cytometry, under hypoxic and oxygenated conditions. The invasion of less-invasive DU-145 cells was not affected by either hypoxia or the presence of HUVECs. However, hypoxia significantly decreased the invasion of PC-3 cells. This hypoxia-induced decrease was attenuated by the presence of HUVECs, whereas under oxygenated conditions, HUVECs did not alter the invasion of PC-3 cells. Cell metabolism changed distinctly with hypoxia and invasion. The endogenous activity of selected extracellular proteases, although altered by hypoxia, did not fully explain the hypoxia-induced changes in invasion. Gene expression profiling indicated that hypoxia affects multiple cellular functions and pathways.

  20. Downregulation of Securin by the variant RNF213 R4810K (rs112735431, G>A) reduces angiogenic activity of induced pluripotent stem cell-derived vascular endothelial cells from moyamoya patients

    Energy Technology Data Exchange (ETDEWEB)

    Hitomi, Toshiaki [Department of Health and Environmental Sciences, Kyoto University, Kyoto (Japan); Habu, Toshiyuki [Radiation Biology Center, Kyoto University, Kyoto (Japan); Kobayashi, Hatasu; Okuda, Hiroko; Harada, Kouji H. [Department of Health and Environmental Sciences, Kyoto University, Kyoto (Japan); Osafune, Kenji [Center for iPS Cell Research and Application (CiRA), Kyoto University, Kyoto (Japan); Taura, Daisuke; Sone, Masakatsu [Department of Medicine and Clinical Science, Kyoto University, Kyoto (Japan); Asaka, Isao; Ameku, Tomonaga; Watanabe, Akira; Kasahara, Tomoko; Sudo, Tomomi; Shiota, Fumihiko [Center for iPS Cell Research and Application (CiRA), Kyoto University, Kyoto (Japan); Hashikata, Hirokuni; Takagi, Yasushi [Department of Neurosurgery, Kyoto University,Kyoto (Japan); Morito, Daisuke [Faculty of Life Sciences, Kyoto Sangyo University, Kyoto (Japan); Miyamoto, Susumu [Department of Neurosurgery, Kyoto University,Kyoto (Japan); Nakao, Kazuwa [Department of Medicine and Clinical Science, Kyoto University, Kyoto (Japan); Koizumi, Akio, E-mail: koizumi.akio.5v@kyoto-u.ac.jp [Department of Health and Environmental Sciences, Kyoto University, Kyoto (Japan)

    2013-08-16

    Highlights: •Angiogenic activities were reduced in iPSECs from MMD patients. •Many mitosis-regulated genes were downregulated in iPSECs from MMD patients. •RNF213 R4810K downregulated Securin and inhibited angiogenic activity. •Securin suppression by siRNA reduced angiogenic activities of iPSECs and HUVECs. -- Abstract: Moyamoya disease (MMD) is a cerebrovascular disease characterized by occlusive lesions in the circle of Willis. The RNF213 R4810K polymorphism increases susceptibility to MMD. Induced pluripotent stem cells (iPSCs) were established from unaffected fibroblast donors with wild-type RNF213 alleles, and from carriers/patients with one or two RNF213 R4810K alleles. Angiogenic activities of iPSC-derived vascular endothelial cells (iPSECs) from patients and carriers were lower (49.0 ± 19.4%) than from wild-type subjects (p < 0.01). Gene expression profiles in iPSECs showed that Securin was down-regulated (p < 0.01) in carriers and patients. Overexpression of RNF213 R4810K downregulated Securin, inhibited angiogenic activity (36.0 ± 16.9%) and proliferation of humanumbilical vein endothelial cells (HUVECs) while overexpression of RNF213 wild type did not. Securin expression was downregulated using RNA interference techniques, which reduced the level of tube formation in iPSECs and HUVECs without inhibition of proliferation. RNF213 R4810K reduced angiogenic activities of iPSECs from patients with MMD, suggesting that it is a promising in vitro model for MMD.

  1. Downregulation of Securin by the variant RNF213 R4810K (rs112735431, G>A) reduces angiogenic activity of induced pluripotent stem cell-derived vascular endothelial cells from moyamoya patients

    International Nuclear Information System (INIS)

    Highlights: •Angiogenic activities were reduced in iPSECs from MMD patients. •Many mitosis-regulated genes were downregulated in iPSECs from MMD patients. •RNF213 R4810K downregulated Securin and inhibited angiogenic activity. •Securin suppression by siRNA reduced angiogenic activities of iPSECs and HUVECs. -- Abstract: Moyamoya disease (MMD) is a cerebrovascular disease characterized by occlusive lesions in the circle of Willis. The RNF213 R4810K polymorphism increases susceptibility to MMD. Induced pluripotent stem cells (iPSCs) were established from unaffected fibroblast donors with wild-type RNF213 alleles, and from carriers/patients with one or two RNF213 R4810K alleles. Angiogenic activities of iPSC-derived vascular endothelial cells (iPSECs) from patients and carriers were lower (49.0 ± 19.4%) than from wild-type subjects (p < 0.01). Gene expression profiles in iPSECs showed that Securin was down-regulated (p < 0.01) in carriers and patients. Overexpression of RNF213 R4810K downregulated Securin, inhibited angiogenic activity (36.0 ± 16.9%) and proliferation of humanumbilical vein endothelial cells (HUVECs) while overexpression of RNF213 wild type did not. Securin expression was downregulated using RNA interference techniques, which reduced the level of tube formation in iPSECs and HUVECs without inhibition of proliferation. RNF213 R4810K reduced angiogenic activities of iPSECs from patients with MMD, suggesting that it is a promising in vitro model for MMD

  2. Oxidized low density lipoprotein increases RANKL level in human vascular cells. Involvement of oxidative stress

    International Nuclear Information System (INIS)

    Highlights: •Oxidized LDL enhances RANKL level in human smooth muscle cells. •The effect of OxLDL is mediated by the transcription factor NFAT. •UVA, H2O2 and buthionine sulfoximine also increase RANKL level. •All these effects are observed in human fibroblasts and endothelial cells. -- Abstract: Receptor Activator of NFκB Ligand (RANKL) and its decoy receptor osteoprotegerin (OPG) have been shown to play a role not only in bone remodeling but also in inflammation, arterial calcification and atherosclerotic plaque rupture. In human smooth muscle cells, Cu2+-oxidized LDL (CuLDL) 10–50 μg/ml increased reactive oxygen species (ROS) and RANKL level in a dose-dependent manner, whereas OPG level was not affected. The lipid extract of CuLDL reproduced the effects of the whole particle. Vivit, an inhibitor of the transcription factor NFAT, reduced the CuLDL-induced increase in RANKL, whereas PKA and NFκB inhibitors were ineffective. LDL oxidized by myeloperoxidase (MPO-LDL), or other pro-oxidant conditions such as ultraviolet A (UVA) irradiation, incubation with H2O2 or with buthionine sulfoximine (BSO), an inhibitor of glutathione synthesis, also induced an oxidative stress and enhanced RANKL level. The increase in RANKL in pro-oxidant conditions was also observed in fibroblasts and endothelial cells. Since RANKL is involved in myocardial inflammation, vascular calcification and plaque rupture, this study highlights a new mechanism whereby OxLDL might, by generation of an oxidative stress, exert a deleterious effect on different cell types of the arterial wall

  3. Poldip2 controls vascular smooth muscle cell migration by regulating focal adhesion turnover and force polarization

    Science.gov (United States)

    Datla, Srinivasa Raju; McGrail, Daniel J.; Vukelic, Sasa; Huff, Lauren P.; Lyle, Alicia N.; Pounkova, Lily; Lee, Minyoung; Seidel-Rogol, Bonnie; Khalil, Mazen K.; Hilenski, Lula L.; Terada, Lance S.; Dawson, Michelle R.; Lassègue, Bernard

    2014-01-01

    Polymerase-δ-interacting protein 2 (Poldip2) interacts with NADPH oxidase 4 (Nox4) and regulates migration; however, the precise underlying mechanisms are unclear. Here, we investigated the role of Poldip2 in focal adhesion turnover, as well as traction force generation and polarization. Poldip2 overexpression (AdPoldip2) in vascular smooth muscle cells (VSMCs) impairs PDGF-induced migration and induces a characteristic phenotype of long cytoplasmic extensions. AdPoldip2 also prevents the decrease in spreading and increased aspect ratio observed in response to PDGF and slightly impairs cell contraction. Moreover, AdPoldip2 blocks focal adhesion dissolution and sustains H2O2 levels in focal adhesions, whereas Poldip2 knockdown (siPoldip2) significantly decreases the number of focal adhesions. RhoA activity is unchanged when focal adhesion dissolution is stimulated in control cells but increases in AdPoldip2-treated cells. Inhibition of RhoA blocks Poldip2-mediated attenuation of focal adhesion dissolution, and overexpression of RhoA or focal adhesion kinase (FAK) reverses the loss of focal adhesions induced by siPoldip2, indicating that RhoA and FAK mediate the effect of Poldip2 on focal adhesions. Nox4 silencing prevents focal adhesion stabilization by AdPoldip2 and induces a phenotype similar to siPoldip2, suggesting a role for Nox4 in Poldip2-induced focal adhesion stability. As a consequence of impaired focal adhesion turnover, PDGF-treated AdPoldip2 cells are unable to reduce and polarize traction forces, a necessary first step in migration. These results implicate Poldip2 in VSMC migration via regulation of focal adhesion turnover and traction force generation in a Nox4/RhoA/FAK-dependent manner. PMID:25063792

  4. Magnolol inhibits migration of vascular smooth muscle cells via cytoskeletal remodeling pathway to attenuate neointima formation

    Energy Technology Data Exchange (ETDEWEB)

    Karki, Rajendra [Division of Pharmacology and Toxicology, School of Pharmacy, University of Missouri-Kansas City (United States); Department of Oriental Medicine Resources, Mokpo National University (Korea, Republic of); Kim, Seong-Bin [Jeollanamdo Development Institute for Korean Traditional Medicine, Jangheung gun, Jeollanamdo (Korea, Republic of); Kim, Dong-Wook, E-mail: dbkim@mokpo.ac.kr [Department of Oriental Medicine Resources, Mokpo National University (Korea, Republic of)

    2013-12-10

    Background: Increased proliferation and migration of vascular smooth muscle cells (VSMCs) contribute importantly to the formation of both atherosclerotic and restenotic lesions. The objective of this study was to investigate the effect of magnolol on VSMC migration. Methods: The proteolytic activity of matrix metalloproteinases (MMPs) in tumor necrosis factor alpha (TNF-α) stimulated VSMCs was performed by gelatin zymography. VSMC migration was assessed by wound healing and Boyden chamber methods. Collagen induced VSMC adhesion was determined by spectrofluorimeter and stress fibers formation was evaluated by fluorescence microscope. The expression of signaling molecules involved in stress fibers formation was determined by western blot. The phosphorylation of myosin light chain (MLC20) was determined by urea-glycerol polyacrylamide gel electrophoresis. Immunohistochemistry was performed to determine the expression of β1-integrin and collagen type I in the injured carotid arteries of rats on day 35 after vascular injury. Results: VSMC migration was strongly inhibited by magnolol without affecting MMPs expression. Also, magnolol inhibited β1-integrin expression, FAK phosphorylation and RhoA and Cdc42 activation to inhibit the collagen induced stress fibers formation. Moreover, magnolol inhibited the phosphorylation of MLC20. Our in vivo results showed that magnolol inhibited β1-integrin expression, collagen type I deposition and FAK phosphorylation in injured carotid arteries without affecting MMP-2 activity. Conclusions: Magnolol inhibited VSMC migration via inhibition of cytoskeletal remodeling pathway to attenuate neointima formation. General significance: This study provides a rationale for further evaluation of magnolol for the management of atherosclerosis and restenosis. - Highlights: • Magnolol strongly inhibited migration of VSMCs. • Magnolol inhibited stress fibers formation. • MLC20 phosphorylation was also inhibited by magnolol. • Anti

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

    Directory of Open Access Journals (Sweden)

    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.

  6. Magnolol inhibits migration of vascular smooth muscle cells via cytoskeletal remodeling pathway to attenuate neointima formation

    International Nuclear Information System (INIS)

    Background: Increased proliferation and migration of vascular smooth muscle cells (VSMCs) contribute importantly to the formation of both atherosclerotic and restenotic lesions. The objective of this study was to investigate the effect of magnolol on VSMC migration. Methods: The proteolytic activity of matrix metalloproteinases (MMPs) in tumor necrosis factor alpha (TNF-α) stimulated VSMCs was performed by gelatin zymography. VSMC migration was assessed by wound healing and Boyden chamber methods. Collagen induced VSMC adhesion was determined by spectrofluorimeter and stress fibers formation was evaluated by fluorescence microscope. The expression of signaling molecules involved in stress fibers formation was determined by western blot. The phosphorylation of myosin light chain (MLC20) was determined by urea-glycerol polyacrylamide gel electrophoresis. Immunohistochemistry was performed to determine the expression of β1-integrin and collagen type I in the injured carotid arteries of rats on day 35 after vascular injury. Results: VSMC migration was strongly inhibited by magnolol without affecting MMPs expression. Also, magnolol inhibited β1-integrin expression, FAK phosphorylation and RhoA and Cdc42 activation to inhibit the collagen induced stress fibers formation. Moreover, magnolol inhibited the phosphorylation of MLC20. Our in vivo results showed that magnolol inhibited β1-integrin expression, collagen type I deposition and FAK phosphorylation in injured carotid arteries without affecting MMP-2 activity. Conclusions: Magnolol inhibited VSMC migration via inhibition of cytoskeletal remodeling pathway to attenuate neointima formation. General significance: This study provides a rationale for further evaluation of magnolol for the management of atherosclerosis and restenosis. - Highlights: • Magnolol strongly inhibited migration of VSMCs. • Magnolol inhibited stress fibers formation. • MLC20 phosphorylation was also inhibited by magnolol. • Anti

  7. Inhaled tolafentrine reverses pulmonary vascular remodeling via inhibition of smooth muscle cell migration

    Directory of Open Access Journals (Sweden)

    Weissmann Norbert

    2005-11-01

    Full Text Available Abstract Background The aim of the study was to assess the chronic effects of combined phosphodiesterase 3/4 inhibitor tolafentrine, administered by inhalation, during monocrotaline-induced pulmonary arterial hypertension (PAH in rats. Methods CD rats were given a single subcutaneous injection of monocrotaline to induce PAH. Four weeks after, rats were subjected to inhalation of tolafentrine or sham nebulization in an unrestrained, whole body aerosol exposure system. In these animals (i the acute pulmonary vasodilatory efficacy of inhaled tolafentrine (ii the anti-remodeling effect of long-term inhalation of tolafentrine (iii the effects of tolafentrine on the expression profile of 96 genes encoding cell adhesion and extracellular matrix regulation were examined. In addition, the inhibitory effect of tolafentrine on ex vivo isolated pulmonary artery SMC cell migration was also investigated. Results Monocrotaline injection provoked severe PAH (right ventricular systolic pressure increased from 25.9 ± 4.0 to 68.9 ± 3.2 after 4 weeks and 74.9 ± 5.1 mmHg after 6 weeks, cardiac output depression and right heart hypertrophy. The media thickness of the pulmonary arteries and the proportion of muscularization of small precapillary resistance vessels increased dramatically, and the migratory response of ex-vivo isolated pulmonary artery smooth muscle cells (PASMC was increased. Micro-arrays and subsequent confirmation with real time PCR demonstrated upregulation of several extracellular matrix regulation and adhesion genes, such as matrixmetalloproteases (MMP 2, 8, 9, 10, 11, 12, 20, Icam, Itgax, Plat and serpinb2. When chronically nebulized from day 28 to 42 (12 daily aerosol maneuvers, after full establishment of severe pulmonary hypertension, tolafentrine reversed about 60% of all hemodynamic abnormalities, right heart hypertrophy and monocrotaline-induced structural lung vascular changes, including the proportion of pulmonary artery

  8. Role of the T cell in the genesis of angiotensin II–induced hypertension and vascular dysfunction

    OpenAIRE

    Tomasz J. Guzik; Hoch, Nyssa E.; Brown, Kathryn A.; McCann, Louise A.; Rahman, Ayaz; Dikalov, Sergey; Goronzy, Jorg; Weyand, Cornelia; Harrison, David G

    2007-01-01

    Hypertension promotes atherosclerosis and is a major source of morbidity and mortality. We show that mice lacking T and B cells (RAG-1−/− mice) have blunted hypertension and do not develop abnormalities of vascular function during angiotensin II infusion or desoxycorticosterone acetate (DOCA)–salt. Adoptive transfer of T, but not B, cells restored these abnormalities. Angiotensin II is known to stimulate reactive oxygen species production via the nicotinamide adenosine dinucleotide phosphate ...

  9. Atrophin Proteins Interact with the Fat1 Cadherin and Regulate Migration and Orientation in Vascular Smooth Muscle Cells*S⃞

    OpenAIRE

    Hou, Rong; Sibinga, Nicholas E. S.

    2009-01-01

    Fat1, an atypical cadherin induced robustly after arterial injury, has significant effects on mammalian vascular smooth muscle cell (VSMC) growth and migration. The related Drosophila protein Fat interacts genetically and physically with Atrophin, a protein essential for development and control of cell polarity. We hypothesized that interactions between Fat1 and mammalian Atrophin (Atr) proteins might contribute to Fat1 effects on VSMCs. Like Fat1, mammalian Atr expres...

  10. Thrombopoietin enhances expression of vascular endothelial growth factor (VEGF) in primitive hematopoietic cells through induction of HIF-1α

    OpenAIRE

    Kirito, Keita; Fox, Norma; Komatsu, Norio; Kaushansky, Kenneth

    2005-01-01

    Thrombopoietin (TPO), the primary regulator of thrombopoiesis, is also an important, nonredundant mediator of hematopoietic stem cell (HSC) development. For example, following transplantation, HSC expansion is approximately 15-fold more robust in normal than in Tpo-/- mice. Vascular endothelial growth factor (VEGF) also plays an important role in HSC development, where it acts in an intracellular autocrine fashion to promote cell survival. Thus, we tested the hypothesis that TPO affects the a...

  11. Sertoli Cells Modulate Testicular Vascular Network Development, Structure, and Function to Influence Circulating Testosterone Concentrations in Adult Male Mice

    Science.gov (United States)

    Rebourcet, Diane; Wu, Junxi; Cruickshanks, Lyndsey; Smith, Sarah E.; Milne, Laura; Fernando, Anuruddika; Wallace, Robert J.; Gray, Calum D.; Hadoke, Patrick W. F.; Mitchell, Rod T.; O'Shaughnessy, Peter J.

    2016-01-01

    The testicular vasculature forms a complex network, providing oxygenation, micronutrients, and waste clearance from the testis. The vasculature is also instrumental to testis function because it is both the route by which gonadotropins are delivered to the testis and by which T is transported away to target organs. Whether Sertoli cells play a role in regulating the testicular vasculature in postnatal life has never been unequivocally demonstrated. In this study we used models of acute Sertoli cell ablation and acute germ cell ablation to address whether Sertoli cells actively influence vascular structure and function in the adult testis. Our findings suggest that Sertoli cells play a key role in supporting the structure of the testicular vasculature. Ablating Sertoli cells (and germ cells) or germ cells alone results in a similar reduction in testis size, yet only the specific loss of Sertoli cells leads to a reduction in total intratesticular vascular volume, the number of vascular branches, and the numbers of small microvessels; loss of germ cells alone has no effect on the testicular vasculature. These perturbations to the testicular vasculature leads to a reduction in fluid exchange between the vasculature and testicular interstitium, which reduces gonadotropin-stimulated circulating T concentrations, indicative of reduced Leydig cell stimulation and/or reduced secretion of T into the vasculature. These findings describe a new paradigm by which the transport of hormones and other factors into and out of the testis may be influenced by Sertoli cells and highlights these cells as potential targets for enhancing this endocrine relationship. PMID:27145015

  12. Targeting etoposide to acute myelogenous leukaemia cells using nanostructured lipid carriers coated with transferrin

    International Nuclear Information System (INIS)

    The aim of the present study was to evaluate the diverse properties of transferrin (Tf)-conjugated nanostructured lipid carriers (NLCs) prepared using three different fatty amines, including stearylamine (SA), dodecylamine (DA) and spermine (SP), and two different methods for Tf coupling. Etoposide-loaded NLCs were prepared by an emulsion–solvent evaporation method followed by probe sonication. Chemical coupling of NLCs with Tf was mediated by an amide linkage between the surface-exposed amino group of the fatty amine and the carboxyl group of the protein. The physical coating was performed in a Ringer-Hepes buffer medium. NLCs were characterized by their particle size, zeta potential, polydispersity index, drug entrapment percentage, drug release profiles and Tf-coupling efficiency. The cytotoxicity of NLCs on K562 acute myelogenous leukaemia cells was studied by MTT assay, and their cellular uptake was studied by a flow cytometry method. SA-containing NLCs showed the lowest particle size, the highest zeta potential and the largest coupling efficiency values. The drug entrapment percentage and the zeta potential decreased after Tf coupling, but the average particle size increased. SP-containing formulations released their drug contents comparatively slower than SA- or DA-containing NLCs. Unconjugated NLCs released moderately more drug than Tf-NLCs. Flow cytometry studies revealed enhanced cellular uptake of Tf-NLCs compared to unconjugated ones. Blocking Tf receptors resulted in a significantly higher cell survival rate for Tf-NLCs. The highest cytotoxic activity was observed in the chemically coupled SA-containing nanoparticles, with an IC50 value of 15-fold lower than free etoposide. (paper)

  13. Targeting etoposide to acute myelogenous leukaemia cells using nanostructured lipid carriers coated with transferrin

    Science.gov (United States)

    Khajavinia, Amir; Varshosaz, Jaleh; Jafarian Dehkordi, Abbas

    2012-10-01

    The aim of the present study was to evaluate the diverse properties of transferrin (Tf)-conjugated nanostructured lipid carriers (NLCs) prepared using three different fatty amines, including stearylamine (SA), dodecylamine (DA) and spermine (SP), and two different methods for Tf coupling. Etoposide-loaded NLCs were prepared by an emulsion-solvent evaporation method followed by probe sonication. Chemical coupling of NLCs with Tf was mediated by an amide linkage between the surface-exposed amino group of the fatty amine and the carboxyl group of the protein. The physical coating was performed in a Ringer-Hepes buffer medium. NLCs were characterized by their particle size, zeta potential, polydispersity index, drug entrapment percentage, drug release profiles and Tf-coupling efficiency. The cytotoxicity of NLCs on K562 acute myelogenous leukaemia cells was studied by MTT assay, and their cellular uptake was studied by a flow cytometry method. SA-containing NLCs showed the lowest particle size, the highest zeta potential and the largest coupling efficiency values. The drug entrapment percentage and the zeta potential decreased after Tf coupling, but the average particle size increased. SP-containing formulations released their drug contents comparatively slower than SA- or DA-containing NLCs. Unconjugated NLCs released moderately more drug than Tf-NLCs. Flow cytometry studies revealed enhanced cellular uptake of Tf-NLCs compared to unconjugated ones. Blocking Tf receptors resulted in a significantly higher cell survival rate for Tf-NLCs. The highest cytotoxic activity was observed in the chemically coupled SA-containing nanoparticles, with an IC50 value of 15-fold lower than free etoposide.

  14. Statins activate GATA-6 and induce differentiated vascular smooth muscle cells

    International Nuclear Information System (INIS)

    The beneficial effects of 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (statins) beyond cholesterol lowering involve their direct actions on vascular smooth muscle cells (VSMCs). However, the effects of statins on phenotypic modulation of VSMCs are unknown. We herein show that simvastatin (Sm) and atorvastatin (At) inhibited DNA synthesis in human aortic VSMCs dose-dependently, while cell toxicity was not observed below the concentration of 1 μM of Sm or 100 nM of At. Stimulating proliferative VSMCs with Sm or At induced the expression of SM-α-actin and SM-MHC, highly specific markers of differentiated phenotype. Sm up-regulated the binding activity of GATA-6 to SM-MHC GATA site and activated the transfected SM-MHC promoter in proliferative VSMCs, while mutating the GATA-6 binding site abolished this activation. Geranylgeranylpyrophosphate (10 μM), an inhibitor of Rho family proteins, abolished the statin-mediated induction of the differentiated phenotype in VSMCs. These findings suggest that statins activate GATA-6 and induce differentiated VSMCs

  15. Multiple Signaling Pathways Contribute to the Thrombin-induced Secretory Phenotype in Vascular Smooth Muscle Cells.

    Science.gov (United States)

    Jeong, Ji Young; Son, Younghae; Kim, Bo-Young; Eo, Seong-Kug; Rhim, Byung-Yong; Kim, Koanhoi

    2015-11-01

    We attempted to investigate molecular mechanisms underlying phenotypic change of vascular smooth muscle cells (VSMCs) by determining signaling molecules involved in chemokine production. Treatment of human aortic smooth muscle cells (HAoSMCs) with thrombin resulted not only in elevated transcription of the (C-C motif) ligand 11 (CCL11) gene but also in enhanced secretion of CCL11 protein. Co-treatment of HAoSMCs with GF109230X, an inhibitor of protein kinase C, or GW5074, an inhibitor of Raf-1 kinase, caused inhibition of ERK1/2 phosphorylation and significantly attenuated expression of CCL11 at transcriptional and protein levels induced by thrombin. Both Akt phosphorylation and CCL11 expression induced by thrombin were attenuated in the presence of pertussis toxin (PTX), an inhibitor of Gi protein-coupled receptor, or LY294002, a PI3K inhibitor. In addition, thrombin-induced production of CCL11 was significantly attenuated by pharmacological inhibition of Akt or MEK which phosphorylates ERK1/2. These results indicate that thrombin is likely to promote expression of CCL11 via PKC/Raf-1/ERK1/2 and PTX-sensitive protease-activated receptors/PI3K/Akt pathways in HAoSMCs. We propose that multiple signaling pathways are involved in change of VSMCs to a secretory phenotype. PMID:26557022

  16. Dysplastic follicular dendritic cells in hyaline-vascular Castleman disease: a rare occurrence creating diagnostic difficulty.

    Science.gov (United States)

    Medina, Edward A; Fuehrer, Neil E; Miller, Frank R; Kinney, Marsha C; Higgins, Russell A

    2016-09-01

    Follicular dendritic cell (FDC) proliferations and dysplastic FDCs can be seen in Hyaline-vascular Castleman disease (HVCD). The association between HVCD and FDC sarcoma is well-documented; dysplastic FDCs may be precursors to FDC sarcoma. Herein, we describe a case of HVCD with strikingly large and dysplastic FDCs, which raised the differential of Hodgkin lymphoma and other neoplasms. Scattered dysplastic FDCs were predominantly in germinal centers and mantle zones, and rarely in interfollicular areas. Although occasional germinal centers contained increased FDCs, no mass forming proliferations were present to suggest FDC sarcoma. Immunostaining demonstrated that the atypical FDCs expressed CD21, clusterin and CXCL13, but not CD23, S100, pankeratin or CD30; they aberrantly expressed epidermal growth factor receptor (EGFR). The present case demonstrates that dysplastic FDCs may be present as isolated cells that require immunophenotyping to distinguish them from malignant entities with similar morphologic features. A variety of FDC markers is required to confirm their origin as the expression of any single marker is not assured, as occurred in this case. Pathologists need be aware of FDC proliferations in HVCD because of their association with FDC sarcoma. Aberrant EGFR expression by dysplastic FDCs may indicate that they are pre-neoplastic and necessitate long-term patient follow-up. PMID:27593552

  17. Cyclic strain-induced endothelial MMP-2: role in vascular smooth muscle cell migration

    International Nuclear Information System (INIS)

    Matrix metalloproteinases (MMPs) play a vital role in vasculature response to hemodynamic stimuli via the degradation of extracellular matrix substrates. In this study, we investigated the putative role of cyclic strain-induced endothelial MMP-2 (and MMP-9) expression and release in modulating bovine aortic smooth muscle cell (BASMC) migration in vitro. Equibiaxial cyclic strain of bovine aortic endothelial cells (BAECs) leads to elevation in cellular MMP-2 (and MMP-9) expression, activity, and secretion into conditioned media, events which were time- and force-dependent. Subsequent incubation of BASMCs with conditioned media from chronically strained BAECs (5%, 24 h) significantly reduces BASMC migration (38 ± 6%), an inhibitory effect which could be completely reversed by targeted siRNA 'knock-down' of MMP-2 (but not MMP-9) expression and activity in BAECs. Moreover, inhibition of strain-mediated MMP-2 expression in BAECs by protein tyrosine kinase (PTK) blockade with genistein (50 μM) was also found to completely reverse this inhibitory effect on BASMC migration. Finally, direct supplementation of recombinant MMP-2 into the BASMC migration assay was found to have no significant effect on migration. However, the effect on BASMC migration of MMP-2 siRNA transfection in BAECs could be reversed by supplementation of recombinant MMP-2 into BAEC media prior to (and for the duration of) strain. These findings reveal a potentially novel role for strain-induced endothelial MMP-2 in regulating vascular SMC migration

  18. Mediterranean diet polyphenols reduce inflammatory angiogenesis through MMP-9 and COX-2 inhibition in human vascular endothelial cells: a potentially protective mechanism in atherosclerotic vascular disease and cancer.

    Science.gov (United States)

    Scoditti, Egeria; Calabriso, Nadia; Massaro, Marika; Pellegrino, Mariangela; Storelli, Carlo; Martines, Giuseppe; De Caterina, Raffaele; Carluccio, Maria Annunziata

    2012-11-15

    Diets with high content of antioxidant polyphenols are associated with low prevalence of cardiovascular diseases and cancer. Inflammatory angiogenesis is a key pathogenic process both in cancer and atherosclerosis, and is tightly regulated by the proinflammatory enzyme cyclooxygenase (COX)-2 and the matrix degrading enzymes matrix metalloproteinases (MMPs). We studied the effects of antioxidant polyphenols from virgin olive oil (oleuropein and hydroxytyrosol) and red wine (resveratrol and quercetin) on endothelial cell angiogenic response in vitro, and explored underlying mechanisms. Cultured endothelial cells were pre-incubated with 0.1-50 μmol/L polyphenols before stimulation with phorbol myristate acetate (PMA). All tested polyphenols reduced endothelial cell tube formation on matrigel and migration in wound healing assays. The reduced angiogenesis was associated with the inhibition of PMA-induced COX-2 protein expression and prostanoid production, as well as MMP-9 protein release and gelatinolytic activity. These effects were accompanied by a significant reduction in the stimulated intracellular reactive oxygen species levels and in the activation of the redox-sensitive transcription factor nuclear factor (NF)-κB. Our findings reveal that olive oil and red wine polyphenols reduce inflammatory angiogenesis in cultured endothelial cells, through MMP-9 and COX-2 inhibition, supporting a potential protective role for dietary polyphenols in atherosclerotic vascular disease and cancer. PMID:22595400

  19. The effect of novel magnetic nanoparticles on vascular endothelial cell function in vitro and in vivo

    Energy Technology Data Exchange (ETDEWEB)

    Su, Le; Han, Lei [Shandong Provincial Key Laboratory of Animal Cells and Developmental Biology, School of Life Science, Shandong University, Jinan 250100 (China); Ge, Fei [Institute of Organic Chemistry, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100 (China); Zhang, Shang Li [Shandong Provincial Key Laboratory of Animal Cells and Developmental Biology, School of Life Science, Shandong University, Jinan 250100 (China); Zhang, Yun [The Key Laboratory of Cardiovascular Remodeling and Function Research, Chinese Ministry of Education and Chinese Ministry of Health, Shandong University Qilu Hospital, Jinan 250100 (China); Zhao, Bao Xiang, E-mail: bxzhao@sdu.edu.cn [Institute of Organic Chemistry, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100 (China); Zhao, Jing [Shandong Provincial Key Laboratory of Animal Cells and Developmental Biology, School of Life Science, Shandong University, Jinan 250100 (China); Miao, Jun Ying, E-mail: miaojy@sdu.edu.cn [Shandong Provincial Key Laboratory of Animal Cells and Developmental Biology, School of Life Science, Shandong University, Jinan 250100 (China); The Key Laboratory of Cardiovascular Remodeling and Function Research, Chinese Ministry of Education and Chinese Ministry of Health, Shandong University Qilu Hospital, Jinan 250100 (China)

    2012-10-15

    Highlights: Black-Right-Pointing-Pointer The novel nanoparticles could internalize in HUVEC and diffuse in the cytoplasm. Black-Right-Pointing-Pointer 1-200 {mu}g/ml MNPs did not affect HUVECs and could be safe to HUVECs in vitro. Black-Right-Pointing-Pointer 400 {mu}g/ml MNPs inhibited cell growth regulated by caveolin-1 and eNOS. Black-Right-Pointing-Pointer 20 mg/kg MNPs damaged endothelium in the aortic root after injected for 3 days. Black-Right-Pointing-Pointer After injected for 6 days and 9 days, the endothelium recovered the integrity. - Abstract: Manufactured nanoparticles are currently used for many fields. However, their potential toxicity provides a growing concern for human health. In our previous study, we prepared novel magnetic nanoparticles (MNPs), which could effectively remove heavy metal ions and cationic dyes from aqueous solution. To understand its biocompatibility, we investigated the effect of the nanoparticles on the function of vascular endothelial cells. The results showed that the nanoparticles were taken up by human umbilical vein endothelial cells (HUVECs) and could inhibit cell proliferation at 400 {mu}g/ml. An increase in nitric oxide (NO) production and endothelial nitric oxide synthase (eNOS) activity were induced, which companied with the decrease in caveolin-1 level. The endothelium in the aortic root was damaged and the NO level in serum was elevated after treated mice with 20 mg/kg nanoparticles for 3 days, but it was integrated after treated with 5 mg/kg nanoparticles. Meanwhile, an increase in eNOS activity and decrease in caveolin-1 level were induced in the endothelium. The data suggested that the low concentration of nanoparticles could not affect the function and viability of VECs. The high concentration of nanoparticles could inhibit VEC proliferation through elevation of the eNOS activity and NO production and thus present toxicity.

  20. Impact of adjuvant inhibition of vascular endothelial growth factor receptor tyrosine kinases on tumor growth delay and local tumor control after fractionated irradiation in human squamous cell carcinomas in nude mice

    International Nuclear Information System (INIS)

    Purpose: Previous experiments have shown that adjuvant inhibition of the vascular endothelial growth factor receptor after fractionated irradiation prolonged tumor growth delay and may also improve local tumor control. To test the latter hypothesis, local tumor control experiments were performed. Methods and materials: Human FaDu and UT-SCC-14 squamous cell carcinomas were studied in nude mice. The vascular endothelial growth factor receptor tyrosine kinase inhibitor PTK787/ZK222584 (50 mg/kg body weight b.i.d.) was administered for 75 days after irradiation with 30 fractions within 6 weeks. Tumor growth time and tumor control dose 50% (TCD50) were determined and compared to controls (carrier without PTK787/ZK222584). Results: Adjuvant administration of PTK787/ZK222584 significantly prolonged tumor growth time to reach 5 times the volume at start of drug treatment by an average of 11 days (95% confidence interval 0.06;22) in FaDu tumors and 29 days (0.6;58) in UT-SCC-14 tumors. In both tumor models, TCD50 values were not statistically significantly different between the groups treated with PTK787/ZK222584 compared to controls. Conclusions: Long-term inhibition of angiogenesis after radiotherapy significantly reduced the growth rate of local recurrences but did not improve local tumor control. This indicates that recurrences after irradiation depend on vascular endothelial growth factor-driven angiogenesis, but surviving tumor cells retain their clonogenic potential during adjuvant antiangiogenic treatment with PTK787/ZK222584

  1. Adhesion and growth of vascular endothelial and smooth muscle cells on artificial vascular prostheses and protein-coated surfaces

    Czech Academy of Sciences Publication Activity Database

    Chlupáč, Jaroslav; Filová, Elena; Brynda, Eduard; Remy-Zolghadri, M.; Bačáková, Lucie

    2005-01-01

    Roč. 3, č. S1 (2005), S8-S9. ISSN 1214-021X. [Cells /6./ - Biological days /18./. 24.10.2005-26.10.2005, České Budějovice] R&D Projects: GA MŠk(CZ) 1M0510; GA AV ČR(CZ) IAA5011301; GA AV ČR(CZ) IAA4050202 Institutional research plan: CEZ:AV0Z50110509 Keywords : tissue engineering * bioartificial vessel * dynamic culture system * hemodynamic bench * fibronectin * collagen * endothelialization * sex -related differences Subject RIV: EI - Biotechnology ; Bionics

  2. Vascular Protective Effect of an Ethanol Extract of Camellia japonica Fruit: Endothelium-Dependent Relaxation of Coronary Artery and Reduction of Smooth Muscle Cell Migration

    OpenAIRE

    Sin-Hee Park; Bong-Sup Shim; Jun-Seong Yoon; Hyun-Ho Lee; Hye-Won Lee; Seok-Bong Yoo; An-Jin Wi; Whoa-Shig Park; Hyun-Jung Kim; Dong-Wok Kim; Min-Ho Oak

    2016-01-01

    Camellia japonica is a popular garden plant in Asia and widely used as cosmetic sources and traditional medicine. However, the possibility that C. japonica affects cardiovascular system remains unclear. The aim of the present study was to evaluate vascular effects of an extract of C. japonica. Vascular reactivity was assessed in organ baths using porcine coronary arteries and inhibition of proliferation and migration were assessed using human vascular smooth muscle cells (VSMCs). All four dif...

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

    OpenAIRE

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

    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 proinfl...

  4. The tight junction protein ZO-2 and Janus kinase 1 mediate intercellular communications in vascular smooth muscle cells

    International Nuclear Information System (INIS)

    Highlights: → The tight junction protein ZO-2 associates with Jak1 in vascular smooth muscle cells via ZO-2 N-terminal fragment. → Jak1 mediates ZO-2 tyrosine phosphorylation and ZO-2 localization to the sites of homotypic intercellular contacts. → The urokinase receptor uPAR regulates ZO-2/Jak1 functional association. → The ZO-2/Jak1/uPAR signaling complex is required for vascular smooth muscle cells functional network formation. -- Abstract: Recent evidence points to a multifunctional role of ZO-2, the tight junction protein of the MAGUK (membrane-associated guanylate kinase-like) family. Though ZO-2 has been found in cell types lacking tight junction structures, such as vascular smooth muscle cells (VSMC), little is known about ZO-2 function in these cells. We provide evidence that ZO-2 mediates specific homotypic cell-to-cell contacts between VSMC. Using mass spectrometry we found that ZO-2 is associated with the non-receptor tyrosine kinase Jak1. By generating specific ZO-2 constructs we further found that the N-terminal fragment of ZO-2 molecule is responsible for this interaction. Adenovirus-based expression of Jak1 inactive mutant demonstrated that Jak1 mediates ZO-2 tyrosine phosphorylation. By means of RNA silencing, expression of Jak1 mutant form and fluorescently labeled ZO-2 fusion protein we further specified that active Jak1, but not Jak1 inactive mutant, mediates ZO-2 localization to the sites of intercellular contacts. We identified the urokinase receptor uPAR as a pre-requisite for these cellular events. Functional requirement of the revealed signaling complex for VSMC network formation was confirmed in experiments using Matrigel and in contraction assay. Our findings imply involvement of the ZO-2 tight junction independent signaling complex containing Jak1 and uPAR in VSMC intercellular communications. This mechanism may contribute to vascular remodeling in occlusive cardiovascular diseases and in arteriogenesis.

  5. The tight junction protein ZO-2 and Janus kinase 1 mediate intercellular communications in vascular smooth muscle cells

    Energy Technology Data Exchange (ETDEWEB)

    Tkachuk, Natalia; Tkachuk, Sergey; Patecki, Margret [Department of Nephrology, Hannover Medical School, Hannover D-30625 (Germany); Kusch, Angelika [Department of Nephrology and Intensive Care Medicine, Charite Campus Virchow-Klinikum, Berlin D-13353 (Germany); Korenbaum, Elena; Haller, Hermann [Department of Nephrology, Hannover Medical School, Hannover D-30625 (Germany); Dumler, Inna, E-mail: dumler.inna@mh-hannover.de [Department of Nephrology, Hannover Medical School, Hannover D-30625 (Germany)

    2011-07-08

    Highlights: {yields} The tight junction protein ZO-2 associates with Jak1 in vascular smooth muscle cells via ZO-2 N-terminal fragment. {yields} Jak1 mediates ZO-2 tyrosine phosphorylation and ZO-2 localization to the sites of homotypic intercellular contacts. {yields} The urokinase receptor uPAR regulates ZO-2/Jak1 functional association. {yields} The ZO-2/Jak1/uPAR signaling complex is required for vascular smooth muscle cells functional network formation. -- Abstract: Recent evidence points to a multifunctional role of ZO-2, the tight junction protein of the MAGUK (membrane-associated guanylate kinase-like) family. Though ZO-2 has been found in cell types lacking tight junction structures, such as vascular smooth muscle cells (VSMC), little is known about ZO-2 function in these cells. We provide evidence that ZO-2 mediates specific homotypic cell-to-cell contacts between VSMC. Using mass spectrometry we found that ZO-2 is associated with the non-receptor tyrosine kinase Jak1. By generating specific ZO-2 constructs we further found that the N-terminal fragment of ZO-2 molecule is responsible for this interaction. Adenovirus-based expression of Jak1 inactive mutant demonstrated that Jak1 mediates ZO-2 tyrosine phosphorylation. By means of RNA silencing, expression of Jak1 mutant form and fluorescently labeled ZO-2 fusion protein we further specified that active Jak1, but not Jak1 inactive mutant, mediates ZO-2 localization to the sites of intercellular contacts. We identified the urokinase receptor uPAR as a pre-requisite for these cellular events. Functional requirement of the revealed signaling complex for VSMC network formation was confirmed in experiments using Matrigel and in contraction assay. Our findings imply involvement of the ZO-2 tight junction independent signaling complex containing Jak1 and uPAR in VSMC intercellular communications. This mechanism may contribute to vascular remodeling in occlusive cardiovascular diseases and in arteriogenesis.

  6. Dependence of InGaN solar cell performance on polarization-induced electric field and carrier lifetime

    International Nuclear Information System (INIS)

    The effects of Mg-induced net acceptor doping concentration and carrier lifetime on the performance of a p—i—n InGaN solar cell are investigated. It is found that the electric field induced by spontaneous and piezoelectric polarization in the i-region could be totally shielded when the Mg-induced net acceptor doping concentration is sufficiently high. The polarization-induced potential barriers are reduced and the short circuit current density is remarkably increased from 0.21 mA/cm2 to 0.95 mA/cm2 by elevating the Mg doping concentration. The carrier lifetime determined by defect density of i-InGaN also plays an important role in determining the photovoltaic properties of solar cell. The short circuit current density severely degrades, and the performance of InGaN solar cell becomes more sensitive to the polarization when carrier lifetime is lower than the transit time. This study demonstrates that the crystal quality of InGaN absorption layer is one of the most important challenges in realizing high efficiency InGaN solar cells. (interdisciplinary physics and related areas of science and technology)

  7. Charge-carrier selective electrodes for organic bulk heterojunction solar cell by contact-printed siloxane oligomers

    International Nuclear Information System (INIS)

    ‘Smart’ (or selective) electrode for charge carriers, both electrons and holes, in organic bulk-heterojunction (BHJ) solar cells using insertion layers made of hydrophobically-recovered and contact-printed siloxane oligomers between electrodes and active material has been demonstrated. The siloxane oligomer insertion layer has been formed at a given interface simply by conformally-contacting a cured slab of polydimethylsiloxane stamp for less than 100 s. All the devices, either siloxane oligomer printed at one interface only or printed at both interfaces, showed efficiency enhancement when compared to non-printed ones. The possible mechanism that is responsible for the observed efficiency enhancement has been discussed based on the point of optimum symmetry and photocurrent analysis. Besides its simplicity and large-area applicability, the demonstrated contact-printing technique does not involve any vacuum or wet processing steps and thus can be very useful for the roll-based, continuous production scheme for organic BHJ solar cells. - Highlights: • Carrier-selective insertion layer in organic bulk heterojunction solar cells • Simple contact-printing of siloxane oligomers improves cell efficiency. • Printed siloxane layer reduces carrier recombination at electrode surfaces. • Siloxane insertion layer works equally well at both electrode surfaces. • Patterned PDMS stamp shortens the printing time within 100 s

  8. Charge-carrier selective electrodes for organic bulk heterojunction solar cell by contact-printed siloxane oligomers

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Hyun-Sik; Khang, Dahl-Young, E-mail: dykhang@yonsei.ac.kr

    2015-08-31

    ‘Smart’ (or selective) electrode for charge carriers, both electrons and holes, in organic bulk-heterojunction (BHJ) solar cells using insertion layers made of hydrophobically-recovered and contact-printed siloxane oligomers between electrodes and active material has been demonstrated. The siloxane oligomer insertion layer has been formed at a given interface simply by conformally-contacting a cured slab of polydimethylsiloxane stamp for less than 100 s. All the devices, either siloxane oligomer printed at one interface only or printed at both interfaces, showed efficiency enhancement when compared to non-printed ones. The possible mechanism that is responsible for the observed efficiency enhancement has been discussed based on the point of optimum symmetry and photocurrent analysis. Besides its simplicity and large-area applicability, the demonstrated contact-printing technique does not involve any vacuum or wet processing steps and thus can be very useful for the roll-based, continuous production scheme for organic BHJ solar cells. - Highlights: • Carrier-selective insertion layer in organic bulk heterojunction solar cells • Simple contact-printing of siloxane oligomers improves cell efficiency. • Printed siloxane layer reduces carrier recombination at electrode surfaces. • Siloxane insertion layer works equally well at both electrode surfaces. • Patterned PDMS stamp shortens the printing time within 100 s.

  9. Fabrication and evaluation of electrohydrodynamic jet 3D printed polycaprolactone/chitosan cell carriers using human embryonic stem cell-derived fibroblasts.

    Science.gov (United States)

    Wu, Yang; Sriram, Gopu; Fawzy, Amr S; Fuh, Jerry Yh; Rosa, Vinicius; Cao, Tong; Wong, Yoke San

    2016-08-01

    Biological function of adherent cells depends on the cell-cell and cell-matrix interactions in three-dimensional space. To understand the behavior of cells in 3D environment and their interactions with neighboring cells and matrix requires 3D culture systems. Here, we present a novel 3D cell carrier scaffold that provides an environment for routine 3D cell growth in vitro We have developed thin, mechanically stable electrohydrodynamic jet (E-jet) 3D printed polycaprolactone and polycaprolactone/Chitosan macroporous scaffolds with precise fiber orientation for basic 3D cell culture application. We have evaluated the application of this technology by growing human embryonic stem cell-derived fibroblasts within these 3D scaffolds. Assessment of cell viability and proliferation of cells seeded on polycaprolactone and polycaprolactone/Chitosan 3D-scaffolds show that the human embryonic stem cell-derived fibroblasts could adhere and proliferate on the scaffolds over time. Further, using confocal microscopy we demonstrate the ability to use fluorescence-labelled cells that could be microscopically monitored in real-time. Hence, these 3D printed polycaprolactone and polycaprolactone/Chitosan scaffolds could be used as a cell carrier for in vitro 3D cell culture-, bioreactor- and tissue engineering-related applications in the future. PMID:27252227

  10. EXPRESSION OF VASCULAR ENDOTHELIAL GROWTH FACTOR IN PRIMARY NON-SMALL CELL LUNG CARCINOMA

    Institute of Scientific and Technical Information of China (English)

    ZHANG Lijian; YANG Guoli; XIE Yuquan; XU Weiguo

    1999-01-01

    Objective: Tumor growth depends on angiogenesis.The aim of this paper is to clarify the relationship between the expression of vascular endothelial growth factor (VEGF)/vascular permeability factor (VPF) and the angiogenesis, or growth, or invasion and prognostic value in Non-Small Cell Lung Cancer (NSCLC).Methods: Microvessei quantification and expression of VEGF was performed immunohistochemically, using multiclonal antibodies against endothelial protein factor Ⅷ-related antigen (F-Ⅷ antigen, or factor Ⅷ) for evaluating the angiogenesis; against VEGF antigen for the expression of VEGF. Results: A total of 53 patients with NSCLC after the radical resection were evaluated.The patients with high and low expression of VEGF were 33 and 20, respectively. A significant higher microvessel density (MVD) was observed in the tumors with high expression of VEGF compared with the tumors with low expression of it (12.17±2.57/mm2 vs 6.01±1.161/mm2, rank sum test, P<0.01). There were 29patients with lymphonodes metastasis in the high expression VEGF/VPF (29/33, 87.88%) group, and 9patients in the low (9/20, 45%) group. There was good correlation between MVD and expression of VEGF (chisquare tests, P<0.001). The overall 5 years survival for 53 patients was 20.75±5.78%; that of the high expression of the VEGF group was 3.03±2.98%; that of the low group was 36.36±13.94%, by Log rank test, P=0.0001.The difference between them had a high significance.There was good correlation between the survival and the expression of VEGF. By the COX's proportional hazard model analysis, the expression of VEGF and MVD was considered to be an independent marker of the prognosis in non-small cell lung cancer. Conclusion: the expression of VEGF has a significant correlation with MVD, growth, invasion, and lymph node metastasis. The increasing of the node metastasis and the size of tumor accompanied the increasing of VEGF/VPF. The cancer patient with higher VEGF and MVD expression might

  11. Pleiotrophin Regulates the Retention and Self-Renewal of Hematopoietic Stem Cells in the Bone Marrow Vascular Niche

    Directory of Open Access Journals (Sweden)

    Heather A. Himburg

    2012-10-01

    Full Text Available The mechanisms through which the bone marrow (BM microenvironment regulates hematopoietic stem cell (HSC fate remain incompletely understood. We examined the role of the heparin-binding growth factor pleiotrophin (PTN in regulating HSC function in the niche. PTN−/− mice displayed significantly decreased BM HSC content and impaired hematopoietic regeneration following myelosuppression. Conversely, mice lacking protein tyrosine phosphatase receptor zeta, which is inactivated by PTN, displayed significantly increased BM HSC content. Transplant studies revealed that PTN action was not HSC autonomous, but rather was mediated by the BM microenvironment. Interestingly, PTN was differentially expressed and secreted by BM sinusoidal endothelial cells within the vascular niche. Furthermore, systemic administration of anti-PTN antibody in mice substantially impaired both the homing of hematopoietic progenitor cells to the niche and the retention of BM HSCs in the niche. PTN is a secreted component of the BM vascular niche that regulates HSC self-renewal and retention in vivo.

  12. Variation of carrier concentration and interface trap density in 8MeV electron irradiated c-Si solar cells

    International Nuclear Information System (INIS)

    The capacitance and conductance measurements were carried out for c-Si solar cells, irradiated with 8 MeV electrons with doses ranging from 5kGy – 100kGy in order to investigate the anomalous degradation of the cells in the radiation harsh environments. Capacitance – Voltage measurements indicate that there is a slight reduction in the carrier concentration upon electron irradiation due to the creation of radiation induced defects. The conductance measurement results reveal that the interface state densities and the trap time constant increases with electron dose due to displacement damages in c-Si solar cells

  13. Loss of Notch3 Signaling in Vascular Smooth Muscle Cells Promotes Severe Heart Failure Upon Hypertension.

    Science.gov (United States)

    Ragot, Hélène; Monfort, Astrid; Baudet, Mathilde; Azibani, Fériel; Fazal, Loubina; Merval, Régine; Polidano, Evelyne; Cohen-Solal, Alain; Delcayre, Claude; Vodovar, Nicolas; Chatziantoniou, Christos; Samuel, Jane-Lise

    2016-08-01

    Hypertension, which is a risk factor of heart failure, provokes adaptive changes at the vasculature and cardiac levels. Notch3 signaling plays an important role in resistance arteries by controlling the maturation of vascular smooth muscle cells. Notch3 deletion is protective in pulmonary hypertension while deleterious in arterial hypertension. Although this latter phenotype was attributed to renal and cardiac alterations, the underlying mechanisms remained unknown. To investigate the role of Notch3 signaling in the cardiac adaptation to hypertension, we used mice with either constitutive Notch3 or smooth muscle cell-specific conditional RBPJκ knockout. At baseline, both genotypes exhibited a cardiac arteriolar rarefaction associated with oxidative stress. In response to angiotensin II-induced hypertension, the heart of Notch3 knockout and SM-RBPJκ knockout mice did not adapt to pressure overload and developed heart failure, which could lead to an early and fatal acute decompensation of heart failure. This cardiac maladaptation was characterized by an absence of media hypertrophy of the media arteries, the transition of smooth muscle cells toward a synthetic phenotype, and an alteration of angiogenic pathways. A subset of mice exhibited an early fatal acute decompensated heart failure, in which the same alterations were observed, although in a more rapid timeframe. Altogether, these observations indicate that Notch3 plays a major role in coronary adaptation to pressure overload. These data also show that the hypertrophy of coronary arterial media on pressure overload is mandatory to initially maintain a normal cardiac function and is regulated by the Notch3/RBPJκ pathway. PMID:27296994

  14. Batroxobin reduces intracellular calcium concentration and inhibits proliferation of vascular smooth muscle cells

    Institute of Scientific and Technical Information of China (English)

    SONG Qing-bin 宋清斌; WEI Min-jie 魏敏杰; DUAN Zhi-quan 段志泉; ZHANG Hai-qiang 张海强; LB Schwartz; XIN Shi-jie 辛世杰

    2004-01-01

    Background Batroxobin (BX), a serine protease used in defibrinogenation and thrombolysis, also has an effect on c-fos gene and growth factor. This study attempted to determine the effects of BX on the proliferation of vascular smooth muscle cells (VSMCs) and calcium metabolism. Methods VSMCs were treated with BX at concentrations of 0.1, 0.3, or 1.0 mmol/L and cell numbers were determined at 0, 24, 48, and 72 hours. Intracellular calcium concentration ([Ca2+]I) was measured using direct fluorescence methods. Results BX was found to suppress proliferation of VSMCs in a dose-dependent fashion with inhibition rates of 18% and 31% by 48 and 72 hours, respectively. In addition, BX decreases basal [Ca2+]I significantly. The basal level in untreated cells was 162.7±33.8 nmol/L, and decreased to 131.5±27.7 nmol/L, 128.3±28.5 nmol/L, and 125.6±34.3 nmol/L with the three concentrations of BX, respectively. Noradrenaline (NE)-induced [Ca2+]I stimulation was also attenuated by BX (0.1 mmol/L BX, 20%±8% inhibition; 0.3 mmol/L BX, 54%±11% inhibition; 1.0 mmol/L BX, 62%±15% inhibition). The ability of NE to stimulate [Ca2+]I was attenuated in cultures in Ca2+-free medium, as was the ability of BX to blunt NE-induced stimulation. Conclusion These findings demonstrate that BX can effectively inhibit proliferation of VSMCs, probably by blocking the release and uptake of Ca2+, thus influencing [Ca2+]I.

  15. Vascular defense responses in rice: peroxida