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

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Jie Su

2015-01-01

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

Macrophages control vascular stem/progenitor cell plasticity through tumor necrosis factor-α-mediated nuclear factor-κB activation.

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Wong, Mei Mei; Chen, Yikuan; Margariti, Andriani; Winkler, Bernhard; Campagnolo, Paola; Potter, Claire; Hu, Yanhua; Xu, Qingbo

2014-03-01

Vascular lineage differentiation of stem/progenitor cells can contribute to both tissue repair and exacerbation of vascular diseases such as in vein grafts. The role of macrophages in controlling vascular progenitor differentiation is largely unknown and may play an important role in graft development. This study aims to identify the role of macrophages in vascular stem/progenitor cell differentiation and thereafter elucidate the mechanisms that are involved in the macrophage- mediated process. We provide in vitro evidence that macrophages can induce endothelial cell (EC) differentiation of the stem/progenitor cells while simultaneously inhibiting their smooth muscle cell differentiation. Mechanistically, both effects were mediated by macrophage-derived tumor necrosis factor-α (TNF-α) via TNF-α receptor 1 and canonical nuclear factor-κB activation. Although the overexpression of p65 enhanced EC (or attenuated smooth muscle cell) differentiation, p65 or TNF-α receptor 1 knockdown using lentiviral short hairpin RNA inhibited EC (or rescued smooth muscle cell) differentiation in response to TNF-α. Furthermore, TNF-α-mediated EC differentiation was driven by direct binding of nuclear factor-κB (p65) to specific VE-cadherin promoter sequences. Subsequent experiments using an ex vivo decellularized vessel scaffold confirmed an increase in the number of ECs and reduction in smooth muscle cell marker expression in the presence of TNF-α. The lack of TNF-α in a knockout mouse model of vein graft decreased endothelialization and significantly increased thrombosis formation. Our study highlights the role of macrophages in directing vascular stem/progenitor cell lineage commitment through TNF-α-mediated TNF-α receptor 1 and nuclear factor-κB activation that is likely required for endothelial repair in vascular diseases such as vein graft.

Effect of gamma rays on electrically evoked contractions of non-vascular smooth muscles (rat vas deferens)

International Nuclear Information System (INIS)

Azroony, R.; Ksies, F.; Alya, G.

2002-10-01

We have tried, in this experiment, to study the modifications of non-vascular smooth muscles contraction induced via gamma rays. Smooth muscular fibers were isolated from the vas deferens of an adult rat and contractions were electrically evoked. Our results show that irradiation activates the VOC (Voltage Operated Channel) type of ionic channels which causes an increasing in the inward flux of Ca 2+ and then causes an increasing in the inner calcium concentration [Ca 2] i, the matter which means an increasing in the force of muscular contraction. Concerning to the response of vas deferens smooth muscles to the activation of membrane receptors, we have tried to study the effects of gamma rays on activating adrenergic and cholinergic receptors, also, we have tried to show the effects of different doses of gamma rays (1, 3, 5, 7 Gy) on regulating the contractile response of this type of smooth muscles. And results show that: - Irradiation increases contraction force, mediated by adrenergic and cholinergic receptors, in a dose dependent manner, with E m ax 1 Gy m axc 3 Gy m ax 5 Gy m ax 7 Gy. There is an important shift on irradiated rats (3, 5, 7 Gy) where the maximum effect of Acetylcholine (E m ax) can be obtained in lower concentrations of Acetylcholine. These results mean that irradiation activates the inward flux of Ca 2+ through the ROC (Receptors Operated Channels) type of ionic channels, which rely, in their activation, on activating the membrane receptors. By comparing these results with the effects of gamma rays on activating vascular adrenergic and cholinergic receptors, we concluded that: Non-vascular smooth muscles (vas deferens) are less sensitive to irradiation in comparing with vascular smooth muscles (venae portal hepatica), and irradiation increases the sensitivity of cholinergic receptors to acetylcholine in the smooth muscular fibers of vas deferens while; if decreases this sensitivity in the smooth muscular fibers of venae portal hepatica

Electron histochemical and autoradiographic studies of vascular smooth muscle cell

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Kameyama, Kohji; Aida, Takeo; Asano, Goro

1982-01-01

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

Static pressure accelerates ox-LDL-induced cholesterol accumulation via SREBP-1-mediated caveolin-1 downregulation in cultured vascular smooth muscle cells

International Nuclear Information System (INIS)

Luo, Di-xian; Xia, Cheng-lai; Li, Jun-mu; Xiong, Yan; Yuan, Hao-yu; TANG, Zhen-Wang; Zeng, Yixin; Liao, Duan-fang

2010-01-01

Research highlights: → Vertical static pressure accelerates ox-LDL-induced cholesterol accumulation in cultured vascular smooth muscle cells. → Static pressure induces SREBP-1 activation. → Static pressure downregulates the expressions of caveolin-1 by activating SREBP-1. → Static pressure also downregulates the transcription of ABCA1 by activating SREBP-1. → Static pressure increases ox-LDL-induced cholesterol accumulation by SREBP-1-mediated caveolin-1 downregulation in vascular smooth muscle cells cultured in vitro. -- Abstract: Objective: To investigate the effect of static pressure on cholesterol accumulation in vascular smooth muscle cells (VSMCs) and its mechanism. Methods: Rat-derived VSMC cell line A10 treated with 50 mg/L ox-LDL and different static pressures (0, 60, 90, 120, 150, 180 mm Hg) in a custom-made pressure incubator for 48 h. Intracellular lipid droplets and lipid levels were assayed by oil red O staining and HPLC; The mRNA levels of caveolin-1 and ABCA1, the protein levels of caveolin-1 SREBP-1 and mature SREBP-1 were respectively detected by RT-PCR or western blot. ALLN, an inhibitor of SREBP metabolism, was used to elevate SREBP-1 protein level in VSMCs treated with static pressure. Results: Static pressures significantly not only increase intracellular lipid droplets in VSMCs, but also elevate cellular lipid content in a pressure-dependent manner. Intracellular free cholesterol (FC), cholesterol ester (CE), total cholesterol (TC) were respectively increased from 60.5 ± 2.8 mg/g, 31.8 ± 0.7 mg/g, 92.3 ± 2.1 mg/g at atmosphere pressure (ATM, 0 mm Hg) to 150.8 ± 9.4 mg/g, 235.9 ± 3.0 mg/g, 386.7 ± 6.4 mg/g at 180 mm Hg. At the same time, static pressures decrease the mRNA and protein levels of caveolin-1, and induce the activation and nuclear translocation of SREBP-1. ALLN increases the protein level of mature SREBP-1 and decreases caveolin-1 expression, so that cellular lipid levels were upregulated. Conclusion: Static

Static pressure accelerates ox-LDL-induced cholesterol accumulation via SREBP-1-mediated caveolin-1 downregulation in cultured vascular smooth muscle cells

Energy Technology Data Exchange (ETDEWEB)

Luo, Di-xian, E-mail: luodixian_2@163.com [Department of Pharmacology, School of Pharmaceutics, Central South University, Changsha 410083, Hunan (China); Institute of Pharmacy and Pharmacology, College of Science and Technology, University of South China, Hengyang 421001, Hunan (China); First People' s Hospital of Chenzhou City, Chenzhou 423000, Hunan (China); Xia, Cheng-lai [Institute of Pharmacy and Pharmacology, College of Science and Technology, University of South China, Hengyang 421001, Hunan (China); Department of Pharmacy, Third Affiliated Hospital Medical College of Guangzhou, Guangzhou 510150, Guangdong (China); Li, Jun-mu [Institute of Pharmacy and Pharmacology, College of Science and Technology, University of South China, Hengyang 421001, Hunan (China); Xiong, Yan [Department of Pharmacology, School of Pharmaceutics, Central South University, Changsha 410083, Hunan (China); Yuan, Hao-yu [Institute of Pharmacy and Pharmacology, College of Science and Technology, University of South China, Hengyang 421001, Hunan (China); Lusong Center for Disease Control and Prevention, Zhuzhou 412000, Hunan (China); TANG, Zhen-Wang; Zeng, Yixin [Institute of Pharmacy and Pharmacology, College of Science and Technology, University of South China, Hengyang 421001, Hunan (China); Liao, Duan-fang, E-mail: dfliao66@yahoo.com.cn [Institute of Pharmacy and Pharmacology, College of Science and Technology, University of South China, Hengyang 421001, Hunan (China); Department of Traditional Chinese Diagnostics, School of Pharmacy, Hunan University of Chinese Medicine, Changsha 420108, Hunan (China)

2010-12-03

Research highlights: {yields} Vertical static pressure accelerates ox-LDL-induced cholesterol accumulation in cultured vascular smooth muscle cells. {yields} Static pressure induces SREBP-1 activation. {yields} Static pressure downregulates the expressions of caveolin-1 by activating SREBP-1. {yields} Static pressure also downregulates the transcription of ABCA1 by activating SREBP-1. {yields} Static pressure increases ox-LDL-induced cholesterol accumulation by SREBP-1-mediated caveolin-1 downregulation in vascular smooth muscle cells cultured in vitro. -- Abstract: Objective: To investigate the effect of static pressure on cholesterol accumulation in vascular smooth muscle cells (VSMCs) and its mechanism. Methods: Rat-derived VSMC cell line A10 treated with 50 mg/L ox-LDL and different static pressures (0, 60, 90, 120, 150, 180 mm Hg) in a custom-made pressure incubator for 48 h. Intracellular lipid droplets and lipid levels were assayed by oil red O staining and HPLC; The mRNA levels of caveolin-1 and ABCA1, the protein levels of caveolin-1 SREBP-1 and mature SREBP-1 were respectively detected by RT-PCR or western blot. ALLN, an inhibitor of SREBP metabolism, was used to elevate SREBP-1 protein level in VSMCs treated with static pressure. Results: Static pressures significantly not only increase intracellular lipid droplets in VSMCs, but also elevate cellular lipid content in a pressure-dependent manner. Intracellular free cholesterol (FC), cholesterol ester (CE), total cholesterol (TC) were respectively increased from 60.5 {+-} 2.8 mg/g, 31.8 {+-} 0.7 mg/g, 92.3 {+-} 2.1 mg/g at atmosphere pressure (ATM, 0 mm Hg) to 150.8 {+-} 9.4 mg/g, 235.9 {+-} 3.0 mg/g, 386.7 {+-} 6.4 mg/g at 180 mm Hg. At the same time, static pressures decrease the mRNA and protein levels of caveolin-1, and induce the activation and nuclear translocation of SREBP-1. ALLN increases the protein level of mature SREBP-1 and decreases caveolin-1 expression, so that cellular lipid levels were

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

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

2018-05-20

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

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

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Soon-Youn Choi

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

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

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

2015-02-01

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

Microtubule Regulation of Kv7 Channels Orchestrates cAMP-Mediated Vasorelaxations in Rat Arterial Smooth Muscle

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Lindman, Johanna; Khammy, Makhala M; Lundegaard, Pia R

2018-01-01

Microtubules can regulate GPCR (G protein-coupled receptor) signaling in various cell types. In vascular smooth muscle, activation of the β-adrenoceptor leads to production of cAMP to mediate a vasorelaxation. Little is known about the role of microtubules in smooth muscle, and given the importance...... of renal and mesenteric arteries that the microtubule stabilizer, paclitaxel, prevented. Sharp microelectrode experiments showed that colchicine treatment caused increased hyperpolarization of mesenteric artery segments in response to isoprenaline. Application of the Kv7 channel blocker, XE991, attenuated...

Effects of the dual TP receptor antagonist and thromboxane synthase inhibitor EV-077 on human endothelial and vascular smooth muscle cells

International Nuclear Information System (INIS)

Petri, Marcelo H.; Tellier, Céline; Michiels, Carine; Ellertsen, Ingvill; Dogné, Jean-Michel; Bäck, Magnus

2013-01-01

Highlights: •EV-077 reduced TNF-α induced inflammation in endothelial cells. •The thromboxane mimetic U69915 enhanced vascular smooth muscle cell proliferation. •EV-077 inhibited smooth muscle cell proliferation. -- Abstract: The prothrombotic mediator thromboxane A 2 is derived from arachidonic acid metabolism through the cyclooxygenase and thromboxane synthase pathways, and transduces its effect through the thromboxane prostanoid (TP) receptor. The aim of this study was to determine the effect of the TP receptor antagonist and thromboxane synthase inhibitor EV-077 on inflammatory markers in human umbilical vein endothelial cells and on human coronary artery smooth muscle cell proliferation. To this end, mRNA levels of different proinflammatory mediators were studied by real time quantitative PCR, supernatants were analyzed by enzyme immune assay, and cell proliferation was assessed using WST-1. EV-077 significantly decreased mRNA levels of ICAM-1 and PTX3 after TNFα incubation, whereas concentrations of 6-keto PGF1α in supernatants of endothelial cells incubated with TNFα were significantly increased after EV-077 treatment. Although U46619 did not alter coronary artery smooth muscle cell proliferation, this thromboxane mimetic enhanced the proliferation induced by serum, insulin and growth factors, which was significantly inhibited by EV-077. In conclusion, EV-077 inhibited TNFα-induced endothelial inflammation and reduced the enhancement of smooth muscle cell proliferation induced by a thromboxane mimetic, supporting that the thromboxane pathway may be associated with early atherosclerosis in terms of endothelial dysfunction and vascular hypertrophy

Effects of the dual TP receptor antagonist and thromboxane synthase inhibitor EV-077 on human endothelial and vascular smooth muscle cells

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Petri, Marcelo H. [Department of Medicine, Karolinska Institutet and Center for Molecular Medicine, Karolinska University Hospital, Stockholm (Sweden); Tellier, Céline; Michiels, Carine [NARILIS, URBC, University of Namur, Namur (Belgium); Ellertsen, Ingvill [Department of Medicine, Karolinska Institutet and Center for Molecular Medicine, Karolinska University Hospital, Stockholm (Sweden); Dogné, Jean-Michel [Department of Pharmacy, Namur Thrombosis and Hemostasis Center, University of Namur, Namur (Belgium); Bäck, Magnus, E-mail: Magnus.Back@ki.se [Department of Medicine, Karolinska Institutet and Center for Molecular Medicine, Karolinska University Hospital, Stockholm (Sweden)

2013-11-15

Highlights: •EV-077 reduced TNF-α induced inflammation in endothelial cells. •The thromboxane mimetic U69915 enhanced vascular smooth muscle cell proliferation. •EV-077 inhibited smooth muscle cell proliferation. -- Abstract: The prothrombotic mediator thromboxane A{sub 2} is derived from arachidonic acid metabolism through the cyclooxygenase and thromboxane synthase pathways, and transduces its effect through the thromboxane prostanoid (TP) receptor. The aim of this study was to determine the effect of the TP receptor antagonist and thromboxane synthase inhibitor EV-077 on inflammatory markers in human umbilical vein endothelial cells and on human coronary artery smooth muscle cell proliferation. To this end, mRNA levels of different proinflammatory mediators were studied by real time quantitative PCR, supernatants were analyzed by enzyme immune assay, and cell proliferation was assessed using WST-1. EV-077 significantly decreased mRNA levels of ICAM-1 and PTX3 after TNFα incubation, whereas concentrations of 6-keto PGF1α in supernatants of endothelial cells incubated with TNFα were significantly increased after EV-077 treatment. Although U46619 did not alter coronary artery smooth muscle cell proliferation, this thromboxane mimetic enhanced the proliferation induced by serum, insulin and growth factors, which was significantly inhibited by EV-077. In conclusion, EV-077 inhibited TNFα-induced endothelial inflammation and reduced the enhancement of smooth muscle cell proliferation induced by a thromboxane mimetic, supporting that the thromboxane pathway may be associated with early atherosclerosis in terms of endothelial dysfunction and vascular hypertrophy.

Identification and characterization of novel smoothelin isoforms in vascular smooth muscle.

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Krämer, J; Quensel, C; Meding, J; Cardoso, M C; Leonhardt, H

2001-01-01

Smoothelin is a cytoskeletal protein specifically expressed in differentiated smooth muscle cells and has been shown to colocalize with smooth muscle alpha actin. In addition to the small smoothelin isoform of 59 kD, we recently identified a large smoothelin isoform of 117 kD. The aim of this study was to identify and characterize novel smoothelin isoforms. The genomic structure and sequence of the smoothelin gene were determined by genomic PCR, RT-PCR and DNA sequencing. Comparison of the cDNA and genomic sequences shows that the small smoothelin isoform is generated by transcription initiation 10 kb downstream of the start site of the large isoform. In addition to the known smoothelin cDNA (c1 isoform) we identified two novel cDNA variants (c2 and c3 isoform) that are generated by alternative splicing within a region, which shows similarity to the spectrin family of F-actin cross-linking proteins. Visceral organs express the c1 form, while the c2 form prevails in well-vascularized tissue as analyzed by RT-PCR. We then generated specific antibodies against the major smoothelin isoforms and could show by Western blotting and immunohistochemistry that the large isoform is specifically expressed in vascular smooth muscle cells, while the small isoform is abundant in visceral smooth muscle. These results strongly suggest that the smoothelin gene contains a vascular and a visceral smooth muscle promoter. The cell-type-specific expression of smoothelin isoforms that are associated with actin filaments may play a role in the modulation of the contractile properties of different smooth muscle cell types. Copyright 2001 S. Karger AG, Basel

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

African Journals Online (AJOL)

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

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

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

2015-05-15

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

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

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

2003-02-01

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

Regulation of insulin-like growth factor I receptors on vascular smooth muscle cells by growth factors and phorbol esters.

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Ververis, J J; Ku, L; Delafontaine, P

1993-06-01

Insulin-like growth factor I (IGF I) is an important mitogen for vascular smooth muscle cells. To characterize regulation of vascular IGF I receptors, we performed radioligand displacement experiments using rat aortic smooth muscle cells (RASMs). Serum deprivation for 48 hours caused a 40% decrease in IGF I receptor number. Exposure of quiescent RASMs to platelet-derived growth factor (PDGF), fibroblast growth factor (FGF), or angiotensin II (Ang II) caused a 1.5-2.0-fold increase in IGF I receptors per cell. After FGF exposure, there was a marked increase in the mitogenic response to IGF I. IGF I downregulated its receptors in the presence of platelet-poor plasma. Stimulation of protein kinase C (PKC) by exposure of quiescent RASMs to phorbol 12-myristate 13-acetate caused a biphasic response in IGF I binding; there was a 42% decrease in receptor number at 45 minutes and a 238% increase at 24 hours. To determine the role of PKC in growth factor-induced regulation of IGF I receptors, we downregulated PKC by exposing RASMs to phorbol 12,13-dibutyrate (PDBu) for 48 hours. PDGF- and FGF- but not Ang II-mediated upregulation of IGF I receptors was completely inhibited in PDBu-treated cells. Thus, acute PKC activation by phorbol esters inhibits IGF I binding, whereas chronic PKC activation increases IGF I binding. PDGF and FGF but not Ang II regulate vascular IGF I receptors through a PKC-dependent pathway. These data provide new insights into the regulation of vascular smooth muscle cell IGF I receptors in vitro and are of potential importance in characterizing vascular proliferative responses in vivo.

The Hippo pathway mediates inhibition of vascular smooth muscle cell proliferation by cAMP.

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Kimura, Tomomi E; Duggirala, Aparna; Smith, Madeleine C; White, Stephen; Sala-Newby, Graciela B; Newby, Andrew C; Bond, Mark

2016-01-01

Inhibition of vascular smooth muscle cell (VSMC) proliferation by intracellular cAMP prevents excessive neointima formation and hence angioplasty restenosis and vein-graft failure. These protective effects are mediated via actin-cytoskeleton remodelling and subsequent regulation of gene expression by mechanisms that are incompletely understood. Here we investigated the role of components of the growth-regulatory Hippo pathway, specifically the transcription factor TEAD and its co-factors YAP and TAZ in VSMC. Elevation of cAMP using forskolin, dibutyryl-cAMP or the physiological agonists, Cicaprost or adenosine, significantly increased phosphorylation and nuclear export YAP and TAZ and inhibited TEAD-luciferase report gene activity. Similar effects were obtained by inhibiting RhoA activity with C3-transferase, its downstream kinase, ROCK, with Y27632, or actin-polymerisation with Latrunculin-B. Conversely, expression of constitutively-active RhoA reversed the inhibitory effects of forskolin on TEAD-luciferase. Forskolin significantly inhibited the mRNA expression of the pro-mitogenic genes, CCN1, CTGF, c-MYC and TGFB2 and this was reversed by expression of constitutively-active YAP or TAZ phospho-mutants. Inhibition of YAP and TAZ function with RNAi or Verteporfin significantly reduced VSMC proliferation. Furthermore, the anti-mitogenic effects of forskolin were reversed by overexpression of constitutively-active YAP or TAZ. Taken together, these data demonstrate that cAMP-induced actin-cytoskeleton remodelling inhibits YAP/TAZ-TEAD dependent expression of pro-mitogenic genes in VSMC. This mechanism contributes novel insight into the anti-mitogenic effects of cAMP in VSMC and suggests a new target for intervention. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

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

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

2018-04-17

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

Biophysical induction of vascular smooth muscle cell podosomes.

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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.

Terminalia chebula Fructus Inhibits Migration and Proliferation of Vascular Smooth Muscle Cells and Production of Inflammatory Mediators in RAW 264.7

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Hyun-Ho Lee

2015-01-01

Full Text Available Pathogenesis of atherosclerosis and neointima formation after angioplasty involves vascular smooth muscle cells (VSMCs migration and proliferation followed by inflammatory responses mediated by recruited macrophages in the neointima. Terminalia chebula is widely used traditional medicine in Asia for its beneficial effects against cancer, diabetes, and bacterial infection. The study was designed to determine whether Terminalia chebula fructus water extract (TFW suppresses VSMC migration and proliferation and inflammatory mediators production in macrophage (RAW 264.7. Our results showed that TFW possessed strong antioxidative effects in 1,1-diphenyl-2-picryl hydrazyl (DPPH scavenging and lipid peroxidation assays. In addition, TFW reduced nitric oxide (NO production, inducible nitric oxide synthase (iNOS, and cyclooxygenase-2 (COX-2 expression in RAW 264.7 cells. Also, TFW inhibited platelet-derived growth factor (PDGF-BB induced VSMC migration as determined by wound healing and Boyden chamber assays. The antimigratory effect of TFW was due to its inhibitory effect on metalloproteinase-9 (MMP-9 expression, focal adhesion kinase (FAK activation, and Rho-family of small GTPases (Cdc42 and RhoA expression in VSMCs. Furthermore, TFW suppressed PDGF-BB induced VSMC proliferation by downregulation of mitogen activated protein kinases (MAPKs signaling molecules. These results suggest that TFW could be a beneficial resource in the prevention of atherosclerosis.

Shear Stress Induces Phenotypic Modulation of Vascular Smooth Muscle Cells via AMPK/mTOR/ULK1-Mediated Autophagy.

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Sun, Liqian; Zhao, Manman; Liu, Aihua; Lv, Ming; Zhang, Jingbo; Li, Youxiang; Yang, Xinjian; Wu, Zhongxue

2018-03-01

Phenotypic modulation of vascular smooth muscle cells (VSMCs) is involved in the pathophysiological processes of the intracranial aneurysms (IAs). Although shear stress has been implicated in the proliferation, migration, and phenotypic conversion of VSMCs, the molecular mechanisms underlying these events are currently unknown. In this study, we investigated whether shear stress(SS)-induced VSMC phenotypic modulation was mediated by autophagy involved in adenosine monophosphate-activated protein kinase (AMPK)/mammalian target of rapamycin (mTOR)/Unc-51-like kinase 1 (ULK1) pathway. The results show that shear stress could inhibit the expression of key VSMC contractile genes and induce pro-inflammatory/matrix-remodeling genes levels, contributing to VSMCs phenotypic switching from a contractile to a synthetic phenotype. More importantly, Shear stress also markedly increased the levels of the autophagy marker microtubule-associated protein light chain 3-II (LC3II), Beclin-1, and p62 degradation. The autophagy inhibitor 3-methyladenine (3-MA) significantly blocked shear-induced phenotypic modulation of VSMCs. To further explore the molecular mechanism involved in shear-induced autophagy, we found that shear stress could activate AMPK/mTOR/ULK1 signaling pathway in VSMCs. Compound C, a pharmacological inhibitor of AMPK, significantly reduced the levels of p-AMPK and p-ULK, enhanced p-mTOR level, and finally decreased LC3II and Beclin-1 level, which suggested that activated AMPK/mTOR/ULK1 signaling was related to shear-mediated autophagy. These results indicate that shear stress promotes VSMC phenotypic modulation through the induction of autophagy involved in activating the AMPK/mTOR/ULK1 pathway.

Key role of microRNA-15a in the KLF4 suppressions of proliferation and angiogenesis in endothelial and vascular smooth muscle cells

International Nuclear Information System (INIS)

Zheng, Xuemei; Li, Aiqin; Zhao, Liang; Zhou, Tengfei; Shen, Qiang; Cui, Qinghua; Qin, Xiaomei

2013-01-01

Highlights: •This is the first demonstration that miR-15a is a novel target gene of KLF4. •A novel finding that KLF4 increases the expression of miR-15a in ECs and VSMCs. •The novel mechanism is that KLF4 inhibits the proliferation of ECs via miR-15a. •The novel mechanism is that KLF4 inhibits the proliferation of VSMCs via miR-15. •miR-15a mediates the anti-angiogenic activity of KLF4. -- Abstract: While recent insights indicate that the transcription factor Krüppel-like factor 4 (KLF4) is indispensable for vascular homeostasis, its exact role in proliferation and angiogenesis and how it functions remain unresolved. Thus, the aim of the present study was to evaluate the role of KLF4 in the proliferations of endothelial and vascular smooth muscle cells, as well as the angiogenesis. The overexpression of KLF4 in endothelial cells significantly impaired tube formation. KLF4 inhibited the formation of a vascular network in implanted Matrigel plugs in nude mice. Importantly, we found that KLF4 significantly upregulated the miR-15a expression in endothelial cells and vascular smooth muscle cells, and conversely, KLF4 depletion reduced the amount of miR-15a. Furthermore, KLF4 blocked cell cycle progression and decreased cyclin D1 expression in endothelial cells and vascular smooth muscle cells through the induction of miR-15a. Intriguingly, the delivery of a miR-15a antagomir to nude mice resulted in marked attenuation of the anti-angiogenic effect of KLF4. Collectively, our present study provide the first evidence that miR-15a as a direct transcriptional target of KLF4 that mediates the anti-proliferative and anti-angiogenic actions of KLF4, which indicates that KLF4 upregulation of miR-15a may represent a therapeutic option to suppress proliferative vascular disorders

Key role of microRNA-15a in the KLF4 suppressions of proliferation and angiogenesis in endothelial and vascular smooth muscle cells

Energy Technology Data Exchange (ETDEWEB)

Zheng, Xuemei; Li, Aiqin; Zhao, Liang; Zhou, Tengfei; Shen, Qiang [Institute of Cardiovascular Science, Peking University Health Science Center, Beijing 100191 (China); Key Laboratory of Molecular Cardiovascular Science of Ministry of Education, Peking University Health Science Center, Beijing 100191 (China); Cui, Qinghua [Department of Biomedical Informatics, Peking University Health Science Center, Beijing 100191 (China); Key Laboratory of Molecular Cardiovascular Science of Ministry of Education, Peking University Health Science Center, Beijing 100191 (China); Qin, Xiaomei, E-mail: xmqin@bjmu.edu.cn [Institute of Cardiovascular Science, Peking University Health Science Center, Beijing 100191 (China); Key Laboratory of Molecular Cardiovascular Science of Ministry of Education, Peking University Health Science Center, Beijing 100191 (China)

2013-08-09

Highlights: •This is the first demonstration that miR-15a is a novel target gene of KLF4. •A novel finding that KLF4 increases the expression of miR-15a in ECs and VSMCs. •The novel mechanism is that KLF4 inhibits the proliferation of ECs via miR-15a. •The novel mechanism is that KLF4 inhibits the proliferation of VSMCs via miR-15. •miR-15a mediates the anti-angiogenic activity of KLF4. -- Abstract: While recent insights indicate that the transcription factor Krüppel-like factor 4 (KLF4) is indispensable for vascular homeostasis, its exact role in proliferation and angiogenesis and how it functions remain unresolved. Thus, the aim of the present study was to evaluate the role of KLF4 in the proliferations of endothelial and vascular smooth muscle cells, as well as the angiogenesis. The overexpression of KLF4 in endothelial cells significantly impaired tube formation. KLF4 inhibited the formation of a vascular network in implanted Matrigel plugs in nude mice. Importantly, we found that KLF4 significantly upregulated the miR-15a expression in endothelial cells and vascular smooth muscle cells, and conversely, KLF4 depletion reduced the amount of miR-15a. Furthermore, KLF4 blocked cell cycle progression and decreased cyclin D1 expression in endothelial cells and vascular smooth muscle cells through the induction of miR-15a. Intriguingly, the delivery of a miR-15a antagomir to nude mice resulted in marked attenuation of the anti-angiogenic effect of KLF4. Collectively, our present study provide the first evidence that miR-15a as a direct transcriptional target of KLF4 that mediates the anti-proliferative and anti-angiogenic actions of KLF4, which indicates that KLF4 upregulation of miR-15a may represent a therapeutic option to suppress proliferative vascular disorders.

TLR4 induces CREB-mediated IL-6 production via upregulation of F-spondin to promote vascular smooth muscle cell migration

Energy Technology Data Exchange (ETDEWEB)

Lee, Guan-Lin [Institute of Cellular and System Medicine, National Health Research Institutes, Zhunan, Taiwan (China); Graduate Institutes of Life Sciences, National Defense Medical Center, Taipei, Taiwan (China); Wu, Jing-Yiing [Institute of Cellular and System Medicine, National Health Research Institutes, Zhunan, Taiwan (China); Yeh, Chang-Ching [Institute of Cellular and System Medicine, National Health Research Institutes, Zhunan, Taiwan (China); Graduate Institutes of Life Sciences, National Defense Medical Center, Taipei, Taiwan (China); Kuo, Cheng-Chin, E-mail: kuocc@nhri.org.tw [Institute of Cellular and System Medicine, National Health Research Institutes, Zhunan, Taiwan (China); Graduate Institutes of Life Sciences, National Defense Medical Center, Taipei, Taiwan (China); Graduate Institute of Basic Medical Science, China Medical University, Taichung, Taiwan (China)

2016-05-13

Toll-like receptor 4 (TLR4) is important in promoting inflammation and vascular smooth muscle cell (VSMC) migration, both of which contribute to atherosclerosis development and progression. But the mechanism underlying the regulation of TLR4 in VSMC migration remains unclear. Stimulation of VSMCs with LPS increased the cellular level of F-spondin which is associated with the regulation of proinflammatory cytokine production. The LPS-induced F-spondin expression depended on TLR4-mediated PI3K/Akt pathway. Suppression of F-spondin level by siRNA inhibited not only F-spondin expression but also LPS-induced phosphorylation of cAMP response element binding protein (CREB) and IL-6 expression, VSMC migration and proliferation as well as MMP9 expression. Moreover, suppression of CREB level by siRNA inhibited TLR4-induced IL-6 production and VSMC migration. Inhibition of F-spondin siRNA on LPS-induced migration was restored by addition of exogenous recombinant mouse IL-6. We conclude that upon ligand binding, TLR4 activates PI3K/Akt signaling to induce F-spondin expression, subsequently control CREB-mediated IL-6 production to promote VSMC migration. These findings provide vital insights into the essential role of F-spondin in VSMC function and will be valuable for developing new therapeutic strategies against atherosclerosis. -- Highlights: •LPS-induced F-spondin expression of VSMCs is via a TLR4/PI3K/Akt signaling. •F-spondin is pivotal for LPS-induced CREB-mediated IL-6 production. •F-spondin is required for LPS-induced VSMC migration and proliferation.

TLR4 induces CREB-mediated IL-6 production via upregulation of F-spondin to promote vascular smooth muscle cell migration

International Nuclear Information System (INIS)

Lee, Guan-Lin; Wu, Jing-Yiing; Yeh, Chang-Ching; Kuo, Cheng-Chin

2016-01-01

Toll-like receptor 4 (TLR4) is important in promoting inflammation and vascular smooth muscle cell (VSMC) migration, both of which contribute to atherosclerosis development and progression. But the mechanism underlying the regulation of TLR4 in VSMC migration remains unclear. Stimulation of VSMCs with LPS increased the cellular level of F-spondin which is associated with the regulation of proinflammatory cytokine production. The LPS-induced F-spondin expression depended on TLR4-mediated PI3K/Akt pathway. Suppression of F-spondin level by siRNA inhibited not only F-spondin expression but also LPS-induced phosphorylation of cAMP response element binding protein (CREB) and IL-6 expression, VSMC migration and proliferation as well as MMP9 expression. Moreover, suppression of CREB level by siRNA inhibited TLR4-induced IL-6 production and VSMC migration. Inhibition of F-spondin siRNA on LPS-induced migration was restored by addition of exogenous recombinant mouse IL-6. We conclude that upon ligand binding, TLR4 activates PI3K/Akt signaling to induce F-spondin expression, subsequently control CREB-mediated IL-6 production to promote VSMC migration. These findings provide vital insights into the essential role of F-spondin in VSMC function and will be valuable for developing new therapeutic strategies against atherosclerosis. -- Highlights: •LPS-induced F-spondin expression of VSMCs is via a TLR4/PI3K/Akt signaling. •F-spondin is pivotal for LPS-induced CREB-mediated IL-6 production. •F-spondin is required for LPS-induced VSMC migration and proliferation.

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

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Sayo Koike

2016-09-01

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

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

Science.gov (United States)

Kurabayashi, Masahiko

2015-05-01

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

Palmitic Acid Induces Osteoblastic Differentiation in Vascular Smooth Muscle Cells through ACSL3 and NF-κB, Novel Targets of Eicosapentaenoic Acid

Science.gov (United States)

Kageyama, Aiko; Matsui, Hiroki; Ohta, Masahiko; Sambuichi, Keisuke; Kawano, Hiroyuki; Notsu, Tatsuto; Imada, Kazunori; Yokoyama, Tomoyuki; Kurabayashi, Masahiko

2013-01-01

Free fatty acids (FFAs), elevated in metabolic syndrome and diabetes, play a crucial role in the development of atherosclerotic cardiovascular disease, and eicosapentaenoic acid (EPA) counteracts many aspects of FFA-induced vascular pathology. Although vascular calcification is invariably associated with atherosclerosis, the mechanisms involved are not completely elucidated. In this study, we tested the hypothesis that EPA prevents the osteoblastic differentiation and mineralization of vascular smooth muscle cells (VSMC) induced by palmitic acid (PA), the most abundant long-chain saturated fatty acid in plasma. PA increased and EPA abolished the expression of the genes for bone-related proteins, including bone morphogenetic protein (BMP)-2, Msx2 and osteopontin in human aortic smooth muscle cells (HASMC). Among the long-chain acyl-CoA synthetase (ACSL) subfamily, ACSL3 expression was predominant in HASMC, and PA robustly increased and EPA efficiently inhibited ACSL3 expression. Importantly, PA-induced osteoblastic differentiation was mediated, at least in part, by ACSL3 activation because acyl-CoA synthetase (ACS) inhibitor or siRNA targeted to ACSL3 completely prevented the PA induction of both BMP-2 and Msx2. Conversely, adenovirus-mediated ACSL3 overexpression enhanced PA-induced BMP-2 and Msx2 expression. In addition, EPA, ACSL3 siRNA and ACS inhibitor attenuated calcium deposition and caspase activation induced by PA. Notably, PA induced activation of NF-κB, and NF-κB inhibitor prevented PA-induction of osteoblastic gene expression and calcium deposition. Immunohistochemistry revealed the prominent expression of ACSL3 in VSMC and macrophages in human non-calcifying and calcifying atherosclerotic plaques from the carotid arteries. These results identify ACSL3 and NF-κB as mediators of PA-induced osteoblastic differentiation and calcium deposition in VSMC and suggest that EPA prevents vascular calcification by inhibiting such a new molecular pathway elicited

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

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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.

Increased expression of matrix metalloproteinase-1 in systemic vessels of preeclamptic women: a critical mediator of vascular dysfunction.

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Estrada-Gutierrez, Guadalupe; Cappello, Renato E; Mishra, Nikita; Romero, Roberto; Strauss, Jerome F; Walsh, Scott W

2011-01-01

This study was conducted to determine the following: (1) whether matrix metalloproteinase-1 (MMP-1) is increased in systemic vessels of preeclamptic women, (2) whether this increase might be mediated by neutrophils, and (3) whether MMP-1 could be responsible for vascular dysfunction. Omental arteries and plasma were collected from healthy pregnant and preeclamptic women. Omental arteries were evaluated for gene and protein expression of MMP-1, collagen type 1α, tissue inhibitor of metalloproteinase-1, and vascular reactivity to MMP-1. Gene and protein expression levels were also evaluated in human vascular smooth muscle cells (VSMCs) co-cultured with activated neutrophils, reactive oxygen species, or tumor necrosis factor α. Vessel expression of MMP-1 and circulating MMP-1 levels were increased in preeclamptic women, whereas vascular expression of collagen or tissue inhibitor of metalloproteinase-1 were down-regulated or unchanged. In cultured VSMCs, the imbalance in collagen-regulating genes of preeclamptic vessels was reproduced by treatment with neutrophils, tumor necrosis factor α, or reactive oxygen species. Chemotaxis studies with cultured cells revealed that MMP-1 promoted recruitment of neutrophils via vascular smooth muscle release of interleukin-8. Furthermore, MMP-1 induced vasoconstriction via protease-activated receptor-1, whose expression was significantly increased in omental arteries of preeclamptic women and in VSMCs co-cultured with neutrophils. Collectively, these findings disclose a novel role for MMP-1 as a mediator of vasoconstriction and vascular dysfunction in preeclampsia. Copyright © 2011 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

Statins activate GATA-6 and induce differentiated vascular smooth muscle cells

International Nuclear Information System (INIS)

Wada, Hiromichi; Abe, Mitsuru; Ono, Koh; Morimoto, Tatsuya; Kawamura, Teruhisa; Takaya, Tomohide; Satoh, Noriko; Fujita, Masatoshi; Kita, Toru; Shimatsu, Akira; Hasegawa, Koji

2008-01-01

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

Statins activate GATA-6 and induce differentiated vascular smooth muscle cells

Energy Technology Data Exchange (ETDEWEB)

Wada, Hiromichi [Division of Translational Research, National Hospital Organization Kyoto Medical Center, 1-1 Mukaihata-cho, Fukakusa, Fushimi-ku, Kyoto 612-8555 (Japan); Abe, Mitsuru; Ono, Koh [Department of Cardiovascular Medicine, Graduate School of Medicine, Kyoto University, Kyoto (Japan); Morimoto, Tatsuya; Kawamura, Teruhisa; Takaya, Tomohide [Division of Translational Research, National Hospital Organization Kyoto Medical Center, 1-1 Mukaihata-cho, Fukakusa, Fushimi-ku, Kyoto 612-8555 (Japan); Satoh, Noriko [Division of Metabolic Research, National Hospital Organization Kyoto Medical Center, Kyoto (Japan); Fujita, Masatoshi [Department of Human Health Sciences, Graduate School of Medicine, Kyoto University, Kyoto (Japan); Kita, Toru [Department of Cardiovascular Medicine, Graduate School of Medicine, Kyoto University, Kyoto (Japan); Shimatsu, Akira [Clinical Research Institute, National Hospital Organization Kyoto Medical Center, Kyoto (Japan); Hasegawa, Koji [Division of Translational Research, National Hospital Organization Kyoto Medical Center, 1-1 Mukaihata-cho, Fukakusa, Fushimi-ku, Kyoto 612-8555 (Japan)

2008-10-03

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 {mu}M of Sm or 100 nM of At. Stimulating proliferative VSMCs with Sm or At induced the expression of SM-{alpha}-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 {mu}M), 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.

Pituitary adenylate cyclase activating polypeptide induces vascular relaxation and inhibits non-vascular smooth muscle activity in the rabbit female genital tract

DEFF Research Database (Denmark)

Steenstrup, B R; Ottesen, B; Jørgensen, M

1994-01-01

In vitro effects of two bioactive forms of pituitary adenylate cyclase activating polypeptide (PACAP): PACAP-38 and PACAP-27 were studied on rabbit vascular and non-vascular smooth muscle. Segments of the ovarian artery and muscle strips from the fallopian tube were used. Two series of experiment...

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-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. PMID:19727411

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

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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.

Role of integrin-linked kinase in vascular smooth muscle cells: Regulation by statins and angiotensin II

International Nuclear Information System (INIS)

Friedrich, Erik B.; Clever, Yvonne P.; Wassmann, Sven; Werner, Nikos; Boehm, Michael; Nickenig, Georg

2006-01-01

Our goal was to characterize the role of integrin-linked kinase (ILK) in vascular smooth muscle cells (VSMC), which play a crucial role in atherogenesis. Transfection of VSMC with wild-type and dominant-negative ILK cDNA constructs revealed that ILK mediates migration and proliferation of VSMC but has no effect on VSMC survival. The pro-atherogenic mediator angiotensin II increases ILK protein expression and kinase activity while statin treatment down-regulates ILK in VSMC. Functionally, ILK is necessary for angiotensin II-mediated VSMC migration and proliferation. In VSMC transduced with dominant-negative ILK, statins mediate an additive inhibition of VSMC migration and proliferation, while transfection with wild-type ILK is sufficient to overcome the inhibitory effects of statin treatment on VSMC migration and proliferation. In vivo, ILK is expressed in VSMC of aortic sections from wild-type mice where it is down-regulated following statin treatment and up-regulated following induction of atherosclerosis in apoE-/- mice. These data identify ILK as a novel target in VSMC for anti-atherosclerotic therapy

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

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Yogita Mistry

2013-01-01

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

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

Energy Technology Data Exchange (ETDEWEB)

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

2016-05-01

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

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

International Nuclear Information System (INIS)

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

2016-01-01

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

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

Science.gov (United States)

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 polyploidization and hypertrophy. Furthermore, the hypertrophic agent angiotensin II induced VSMC polyploidization in an Akt1-dependent manner. These results demonstrate that Akt1 regulates ploidy levels in VSMCs and contributes to vascular smooth muscle polyploidization and hypertrophy during hypertension. PMID:11032861

Interleukin-6 downregulated vascular smooth muscle cell contractile proteins via ATG4B-mediated autophagy in thoracic aortic dissection.

Science.gov (United States)

An, Zhao; Qiao, Fan; Lu, Qijue; Ma, Ye; Liu, Yang; Lu, Fanglin; Xu, Zhiyun

2017-12-01

Interleukin-6 (IL-6) overexpression played an important role in the pathogenesis of thoracic aortic dissection (TAD). Our previous study found enhanced autophagy accompanying with contractile proteins α smooth muscle actin (α-SMA) and smooth muscle 22α (SM22α) degradation in TAD aortic vascular smooth muscle cells (VSMCs). Autophagy is an important way for intracellular proteins degradation, while IL-6 has been found as a contributing factor of autophagy in some cancers. These indicated IL-6 might contribute to the occurrence of TAD by promoting autophagy-induced contractile proteins degradation, which has not been investigated. The aim of the present study is to verify this hypothesis and investigate the mechanism of it. We collected 10 TAD and 10 control aortic specimens from patients underwent TAD surgical repair and coronary artery bypass grafting, respectively. Quantitative real-time polymerase chain reaction was used to detect mRNA expression. Protein expression level was assessed by enzyme-linked immunosorbent assay, western blot, and immunohistochemistry. Microtubule-associated protein 1 light chain 3 beta overexpression adenovirus with green and red fluorescent protein tags and transmission electron microscopy were used to detect autophagy level in VSMCs. 3-Methyladenine (3-MA) and chloroquine were used to block autophagy in human VSMCs. Experiment results showed that the expression of IL-6 was significantly increased accompanying with up-regulated autophagy in TAD aortic wall compared with controls. In vitro results showed that IL-6 stimulation decreased the expression of VSMCs contractile proteins α-SMA and SM22α accompanying with up-regulated autophagy. Blocking autophagy with 3-MA or chloroquine inhibited IL-6 induced α-SMA and SM22α degradation. Further investigation showed that autophagy-related 4B cysteine peptidase (ATG4B) was significantly overexpressed in TAD aortic wall and played important role in IL-6 induced autophagy up

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

Science.gov (United States)

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

2017-04-01

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

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

Directory of Open Access Journals (Sweden)

Takuji Machida

2016-12-01

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

Shh mediates PDGF-induced contractile-to-synthetic phenotypic modulation in vascular smooth muscle cells through regulation of KLF4

Energy Technology Data Exchange (ETDEWEB)

Zeng, Qiu [Department of Vascular Surgery, 1st Affiliated Hospital of Chongqing Medical University, Chongqing 400016 (China); Wei, Bin [Department of Dermatology, 1st Affiliated Hospital of Chongqing Medical University, Chongqing 400016 (China); Zhao, Yu; Wang, Xuehu; Fu, Qining; Liu, Hong [Department of Vascular Surgery, 1st Affiliated Hospital of Chongqing Medical University, Chongqing 400016 (China); Li, Fenghe, E-mail: lfh_cmu@126.com [Department of Vascular Surgery, 1st Affiliated Hospital of Chongqing Medical University, Chongqing 400016 (China)

2016-07-01

Platelet-derived growth factor (PDGF) is known to induce phenotypic switching of vascular smooth muscle cells (VSMCs) from contractile to a pathological synthetic state, which played an essential role in proliferation of VSMCs. Sonic hedgehog (Shh) contributes to the proliferation of VSMCs when induced by PDGF. Here, we investigated the probable role of Shh in PDGF-induced VSMC dedifferentiation and its underlying mechanisms. We found that PDGF stimulated Shh expression in VSMCs, which was mediated by activation of PDGFRβ/ERK1/2 cell signaling pathway. Further, we found PDGF-induced VSMC phenotypic modulation was accompanied by up-regulation of Shh/Gli family zinc finger 2 (Gli2) signaling and Krüppel-like factor 4 (KLF4). When inhibited Shh in the presence of PDGF, the expressions of KLF4 and VSMC dedifferentiation markers were down-regulated and the effect of PDGF in inducing VSMC dedifferentiation was blocked. In the absence of PDGF, Shh signaling activation increased the expression of KLF4 and promoted VSMC dedifferentiation. The results indicate Shh participated in the regulation of PDGF-induced VSMC dedifferentiation. Finally, we found that KLF4 was closely involved in this process. On inhibition of KLF4, PDGF induced VSMC dedifferentiation was abrogated, even in the presence of Shh. Taken together, the results provide critical insights into the newly discovered role of Shh in phenotypic modulation of VSMCs which depends on KLF4. - Highlights: • Shh as a downstream effector of PDGF participates in PDGF-induced VSMC phenotypic modulation. • Shh can promote VSMC phenotypic switching from contractile to synthetic state. • Shh mediates VSMC phenotypic modulation through regulation of KLF4.

Shh mediates PDGF-induced contractile-to-synthetic phenotypic modulation in vascular smooth muscle cells through regulation of KLF4

International Nuclear Information System (INIS)

Zeng, Qiu; Wei, Bin; Zhao, Yu; Wang, Xuehu; Fu, Qining; Liu, Hong; Li, Fenghe

2016-01-01

Platelet-derived growth factor (PDGF) is known to induce phenotypic switching of vascular smooth muscle cells (VSMCs) from contractile to a pathological synthetic state, which played an essential role in proliferation of VSMCs. Sonic hedgehog (Shh) contributes to the proliferation of VSMCs when induced by PDGF. Here, we investigated the probable role of Shh in PDGF-induced VSMC dedifferentiation and its underlying mechanisms. We found that PDGF stimulated Shh expression in VSMCs, which was mediated by activation of PDGFRβ/ERK1/2 cell signaling pathway. Further, we found PDGF-induced VSMC phenotypic modulation was accompanied by up-regulation of Shh/Gli family zinc finger 2 (Gli2) signaling and Krüppel-like factor 4 (KLF4). When inhibited Shh in the presence of PDGF, the expressions of KLF4 and VSMC dedifferentiation markers were down-regulated and the effect of PDGF in inducing VSMC dedifferentiation was blocked. In the absence of PDGF, Shh signaling activation increased the expression of KLF4 and promoted VSMC dedifferentiation. The results indicate Shh participated in the regulation of PDGF-induced VSMC dedifferentiation. Finally, we found that KLF4 was closely involved in this process. On inhibition of KLF4, PDGF induced VSMC dedifferentiation was abrogated, even in the presence of Shh. Taken together, the results provide critical insights into the newly discovered role of Shh in phenotypic modulation of VSMCs which depends on KLF4. - Highlights: • Shh as a downstream effector of PDGF participates in PDGF-induced VSMC phenotypic modulation. • Shh can promote VSMC phenotypic switching from contractile to synthetic state. • Shh mediates VSMC phenotypic modulation through regulation of KLF4.

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

Energy Technology Data Exchange (ETDEWEB)

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

2015-12-25

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

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

International Nuclear Information System (INIS)

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

2015-01-01

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

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

NARCIS (Netherlands)

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

2008-01-01

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

Tungstate-targeting of BKαβ1 channels tunes ERK phosphorylation and cell proliferation in human vascular smooth muscle.

Directory of Open Access Journals (Sweden)

Ana Isabel Fernández-Mariño

Full Text Available Despite the substantial knowledge on the antidiabetic, antiobesity and antihypertensive actions of tungstate, information on its primary target/s is scarce. Tungstate activates both the ERK1/2 pathway and the vascular voltage- and Ca2+-dependent large-conductance BKαβ1 potassium channel, which modulates vascular smooth muscle cell (VSMC proliferation and function, respectively. Here, we have assessed the possible involvement of BKαβ1 channels in the tungstate-induced ERK phosphorylation and its relevance for VSMC proliferation. Western blot analysis in HEK cell lines showed that expression of vascular BKαβ1 channels potentiates the tungstate-induced ERK1/2 phosphorylation in a Gi/o protein-dependent manner. Tungstate activated BKαβ1 channels upstream of G proteins as channel activation was not altered by the inhibition of G proteins with GDPβS or pertussis toxin. Moreover, analysis of Gi/o protein activation measuring the FRET among heterologously expressed Gi protein subunits suggested that tungstate-targeting of BKαβ1 channels promotes G protein activation. Single channel recordings on VSMCs from wild-type and β1-knockout mice indicated that the presence of the regulatory β1 subunit was essential for the tungstate-mediated activation of BK channels in VSMCs. Moreover, the specific BK channel blocker iberiotoxin lowered tungstate-induced ERK phosphorylation by 55% and partially reverted (by 51% the tungstate-produced reduction of platelet-derived growth factor (PDGF-induced proliferation in human VSMCs. Our observations indicate that tungstate-targeting of BKαβ1 channels promotes activation of PTX-sensitive Gi proteins to enhance the tungstate-induced phosphorylation of ERK, and inhibits PDGF-stimulated cell proliferation in human vascular smooth muscle.

Upregulation of decorin by FXR in vascular smooth muscle cells

International Nuclear Information System (INIS)

He Fengtian; Zhang Qiuhong; Kuruba, Ramalinga; Gao Xiang; Li Jiang; Li Yong; Gong Wei; Jiang, Yu; Xie Wen; Li Song

2008-01-01

Decorin is a member of the family of small leucine-rich proteoglycans that are present in blood vessels and synthesized by vascular smooth muscle cells (VSMCs). Decorin plays complex roles in both normal vascular physiology and the pathogenesis of various types of vascular disorders. However, the mechanisms of regulation of decorin expression in vasculature are not clearly understood. Particularly little information is available about a role of nuclear receptors in the regulation of decorin expression. In the present study, we report that activation of vascular FXR by a specific ligand resulted in upregulation of decorin at the levels of both mRNA and protein. FXR appears to induce decorin expression at a transcriptional level because (1) upregulation of decorin mRNA expression was abolished by the treatment of a transcription inhibitor, actinomycin D; and (2) decorin promoter activity was significantly increased by activation of FXR. Functional analysis of human decorin promoter identified an imperfect inverted repeat DNA motif, IR8 (-2313TGGTCAtagtgtcaTGACCT-2294), as a likely FXR-responsive element that is involved in decorin regulation

Effects of (-)-desmethoxyverapamil on heart and vascular smooth muscle

International Nuclear Information System (INIS)

Nawrath, H.; Raschack, M.

1987-01-01

(-)-Desmethoxyverapamil [also known as (-)-devapamil or (-)-D888] has been developed as a verapamil type radioligand for the study of calcium channels. In the present investigation, the effects of (-)-desmethoxyverapamil on action potential (AP) and force of contraction in heart muscle preparations and on tension and 45 Ca influx in vascular smooth muscle are described. In part, the effects were compared with the (+)-isomer of desmethoxyverapamil and the isomers of both verapamil and methoxyverapamil. In atrial and/or ventricular heart muscle preparations from guinea pigs, cats and man, (-)-desmethoxyverapamil decreased the force of contraction and shortened the AP duration. Slow response APs were depressed, whereas dV/dtmax of phase 0 of the AP remained unchanged. The rank order of potency of the (-)-isomers was as follows: desmethoxyverapamil greater than methoxyverapamil greater than verapamil. Potassium-induced contractures and 45 Ca influx were depressed by the (-)-isomers of desmethoxyverapamil, methoxyverapamil and verapamil in the same potency rank order as observed in heart muscle. The (+)-isomers exerted qualitatively similar effects at about 10 to 200 times higher concentrations. Correspondingly, the increase in potency of the racemic mixtures of the drugs was accompanied by increases in stereoselectivity. It is concluded that (-)-desmethoxyverapamil is the most potent stereoselective calcium antagonist of the verapamil type with respect to its effects on heart and vascular smooth muscle

Effects of (-)-desmethoxyverapamil on heart and vascular smooth muscle

Energy Technology Data Exchange (ETDEWEB)

Nawrath, H.; Raschack, M.

1987-09-01

(-)-Desmethoxyverapamil (also known as (-)-devapamil or (-)-D888) has been developed as a verapamil type radioligand for the study of calcium channels. In the present investigation, the effects of (-)-desmethoxyverapamil on action potential (AP) and force of contraction in heart muscle preparations and on tension and /sup 45/Ca influx in vascular smooth muscle are described. In part, the effects were compared with the (+)-isomer of desmethoxyverapamil and the isomers of both verapamil and methoxyverapamil. In atrial and/or ventricular heart muscle preparations from guinea pigs, cats and man, (-)-desmethoxyverapamil decreased the force of contraction and shortened the AP duration. Slow response APs were depressed, whereas dV/dtmax of phase 0 of the AP remained unchanged. The rank order of potency of the (-)-isomers was as follows: desmethoxyverapamil greater than methoxyverapamil greater than verapamil. Potassium-induced contractures and /sup 45/Ca influx were depressed by the (-)-isomers of desmethoxyverapamil, methoxyverapamil and verapamil in the same potency rank order as observed in heart muscle. The (+)-isomers exerted qualitatively similar effects at about 10 to 200 times higher concentrations. Correspondingly, the increase in potency of the racemic mixtures of the drugs was accompanied by increases in stereoselectivity. It is concluded that (-)-desmethoxyverapamil is the most potent stereoselective calcium antagonist of the verapamil type with respect to its effects on heart and vascular smooth muscle.

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.

Smooth muscle LDL receptor-related protein-1 deletion induces aortic insufficiency and promotes vascular cardiomyopathy in mice.

Directory of Open Access Journals (Sweden)

Joshua E Basford

Full Text Available Valvular disease is common in patients with Marfan syndrome and can lead to cardiomyopathy. However, some patients develop cardiomyopathy in the absence of hemodynamically significant valve dysfunction, suggesting alternative mechanisms of disease progression. Disruption of LDL receptor-related protein-1 (Lrp1 in smooth muscle cells has been shown to cause vascular pathologies similar to Marfan syndrome, with activation of smooth muscle cells, vascular dysfunction and aortic aneurysms. This study used echocardiography and blood pressure monitoring in mouse models to determine whether inactivation of Lrp1 in vascular smooth muscle leads to cardiomyopathy, and if so, whether the mechanism is a consequence of valvular disease. Hemodynamic changes during treatment with captopril were also assessed. Dilation of aortic roots was observed in young Lrp1-knockout mice and progressed as they aged, whereas no significant aortic dilation was detected in wild type littermates. Diastolic blood pressure was lower and pulse pressure higher in Lrp1-knockout mice, which was normalized by treatment with captopril. Aortic dilation was followed by development of aortic insufficiency and subsequent dilated cardiomyopathy due to valvular disease. Thus, smooth muscle cell Lrp1 deficiency results in aortic dilation and insufficiency that causes secondary cardiomyopathy that can be improved by captopril. These findings provide novel insights into mechanisms of cardiomyopathy associated with vascular activation and offer a new model of valvular cardiomyopathy.

31P-nuclear magnetic resonance analysis of extracts of vascular smooth muscle

International Nuclear Information System (INIS)

Barron, J.T.; Messer, J.V.; Glonek, Thomas

1986-01-01

31 P-nuclear magnetic resonance spectroscopy was used to assess phosphate metabolites in perchloric acid extracts of rabbit aorta. In addition to the high energy phosphates, several other phosphorus compounds were detected and quantified. Most notable was the presence of a prominent phosphomonoester compound appearing at a chemical shift of 3.86 delta. This compound constituted 26% of the total extractable tissue phosphorus and is tentatively identified as ribose-5-phosphate, a pentose phosphate pathway intermediate. While ATP and phosphocreatine did not change during glucose and oxygen deprivation or during prolonged muscle contraction, the 3.86delta phosphate decreased significantly. Furthermore, theophylline, an agent that increases intracellular cAMP, also decreased the level of the 3.86 delta phosphate. These results are consistent with the concept that intermediate metabolism sustains high energy phosphate pools in vascular smooth muscle in the steady state under various conditions. The pentose phosphate pathway may play an important role in vascular smooth muscle metabolism. (author)

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

Science.gov (United States)

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

2012-01-01

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

KCl cotransport regulation and protein kinase G in cultured vascular smooth muscle cells.

Science.gov (United States)

Adragna, N C; Zhang, J; Di Fulvio, M; Lincoln, T M; Lauf, P K

2002-05-15

K-Cl cotransport is activated by vasodilators in erythrocytes and vascular smooth muscle cells and its regulation involves putative kinase/phosphatase cascades. N-ethylmaleimide (NEM) activates the system presumably by inhibiting a protein kinase. Nitrovasodilators relax smooth muscle via cGMP-dependent activation of protein kinase G (PKG), a regulator of membrane channels and transporters. We investigated whether PKG regulates K-Cl cotransport activity or mRNA expression in normal, PKG-deficient-vector-only-transfected (PKG-) and PKG-catalytic-domain-transfected (PKG+) rat aortic smooth muscle cells. K-Cl cotransport was calculated as the Cl-dependent Rb influx, and mRNA was determined by semiquantitative RT-PCR. Baseline K-Cl cotransport was higher in PKG+ than in PKG- cells (p <0.01). At 0.5 mM, NEM stimulated K-Cl cotransport by 5-fold in PKG- but not in PKG+ cells. However, NEM was more potent although less effective to activate K-Cl cotransport in normal (passage 1-3) and PKG+ than in PKG- cells. In PKG- cells, [(dihydroindenyl) oxy] alkanoic acid (300 mM) but not furosemide (1 mM) inhibited K-Cl cotransport. Furthermore, no difference in K-Cl cotransport mRNA expression was observed between these cells. In conclusion, this study shows that manipulation of PKG expression in vascular smooth muscle cells affects K-Cl cotransport activity and its activation by NEM.

Anti-atherosclerotic plants which modulate the phenotype of vascular smooth muscle cells.

Science.gov (United States)

Saleh Al-Shehabi, Tuqa; Iratni, Rabah; Eid, Ali H

2016-10-15

Cardiovascular disease (CVD) remains the leading cause of global death, with atherosclerosis being a major contributor to this mortality. Several mechanisms are implicated in the pathogenesis of this disease. A key element in the development and progression of atherosclerotic lesions is the phenotype of vascular smooth muscle cells. Under pathophysiologic conditions such as injury, these cells switch from a contractile to a synthetic phenotype that often possesses high proliferative and migratory capacities. Despite major advances made in the management and treatment of atherosclerosis, mortality associated with this disease remains high. This mandates that other approaches be sought. Herbal medicine, especially for the treatment of CVD, has been gaining more attention in recent years. This is in no small part due to the evidence-based values associated with the consumption of many plants as well as the relatively cheaper prices, easier access and conventional folk medicine "inherited" over generations. Sections: In this review, we provide a brief introduction about the pathogenesis of atherosclerosis then we highlight the role of vascular smooth muscle cells in this disease, especially when a phenotypic switch of these cells arises. We then thoroughly discuss the various plants that show potentially beneficial effects as anti-atherosclerotic, with prime attention given to herbs and plants that inhibit the phenotypic switch of vascular smooth muscle cells. Accumulating evidence provides the justification for the use of botanicals in the treatment or prevention of atherosclerosis. However, further studies, especially clinical ones, are warranted to better define several pharmacological parameters of these herbs, such as toxicity, tolerability, and efficacy. Copyright © 2015 Elsevier Ltd. All rights reserved.

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

International Nuclear Information System (INIS)

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

2007-01-01

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

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

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

2016-09-01

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

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

Towards the therapeutic use of vascular smooth muscle progenitor cells.

Science.gov (United States)

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

2012-07-15

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

Mitochondrial metabolism and the control of vascular smooth muscle cell proliferation

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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.

Emerging Role of Angiotensin Type 2 Receptor (AT2R)/Akt/NO Pathway in Vascular Smooth Muscle Cell in the Hyperthyroidism

Science.gov (United States)

Carrillo-Sepúlveda, Maria Alícia; Ceravolo, Graziela S.; Furstenau, Cristina R.; Monteiro, Priscilla de Souza; Bruno-Fortes, Zuleica; Carvalho, Maria Helena; Laurindo, Francisco R.; Tostes, Rita C.; Webb, R. Clinton; Barreto-Chaves, Maria Luiza M.

2013-01-01

Hyperthyroidism is characterized by increased vascular relaxation and decreased vascular contraction and is associated with augmented levels of triiodothyronine (T3) that contribute to the diminished systemic vascular resistance found in this condition. T3 leads to augmented NO production via PI3K/Akt signaling pathway, which in turn causes vascular smooth muscle cell (VSMC) relaxation; however, the underlying mechanisms involved remain largely unknown. Evidence from human and animal studies demonstrates that the renin-angiotensin system (RAS) plays a crucial role in vascular function and also mediates some of cardiovascular effects found during hyperthyroidism. Thus, in this study, we hypothesized that type 2 angiotensin II receptor (AT2R), a key component of RAS vasodilatory actions, mediates T3 induced-decreased vascular contraction. Marked induction of AT2R expression was observed in aortas from T3-induced hyperthyroid rats (Hyper). These vessels showed decreased protein levels of the contractile apparatus: α-actin, calponin and phosphorylated myosin light chain (p-MLC). Vascular reactivity studies showed that denuded aortic rings from Hyper rats exhibited decreased maximal contractile response to angiotensin II (AngII), which was attenuated in aortic rings pre-incubated with an AT2R blocker. Further study showed that cultured VSMC stimulated with T3 (0.1 µmol/L) for 24 hours had increased AT2R gene and protein expression. Augmented NO levels and decreased p-MLC levels were found in VSMC stimulated with T3, both of which were reversed by a PI3K/Akt inhibitor and AT2R blocker. These findings indicate for the first time that the AT2R/Akt/NO pathway contributes to decreased contractile responses in rat aorta, promoted by T3, and this mechanism is independent from the endothelium. PMID:23637941

Emerging role of angiotensin type 2 receptor (AT2R/Akt/NO pathway in vascular smooth muscle cell in the hyperthyroidism.

Directory of Open Access Journals (Sweden)

Maria Alícia Carrillo-Sepúlveda

Full Text Available Hyperthyroidism is characterized by increased vascular relaxation and decreased vascular contraction and is associated with augmented levels of triiodothyronine (T3 that contribute to the diminished systemic vascular resistance found in this condition. T3 leads to augmented NO production via PI3K/Akt signaling pathway, which in turn causes vascular smooth muscle cell (VSMC relaxation; however, the underlying mechanisms involved remain largely unknown. Evidence from human and animal studies demonstrates that the renin-angiotensin system (RAS plays a crucial role in vascular function and also mediates some of cardiovascular effects found during hyperthyroidism. Thus, in this study, we hypothesized that type 2 angiotensin II receptor (AT2R, a key component of RAS vasodilatory actions, mediates T3 induced-decreased vascular contraction. Marked induction of AT2R expression was observed in aortas from T3-induced hyperthyroid rats (Hyper. These vessels showed decreased protein levels of the contractile apparatus: α-actin, calponin and phosphorylated myosin light chain (p-MLC. Vascular reactivity studies showed that denuded aortic rings from Hyper rats exhibited decreased maximal contractile response to angiotensin II (AngII, which was attenuated in aortic rings pre-incubated with an AT2R blocker. Further study showed that cultured VSMC stimulated with T3 (0.1 µmol/L for 24 hours had increased AT2R gene and protein expression. Augmented NO levels and decreased p-MLC levels were found in VSMC stimulated with T3, both of which were reversed by a PI3K/Akt inhibitor and AT2R blocker. These findings indicate for the first time that the AT2R/Akt/NO pathway contributes to decreased contractile responses in rat aorta, promoted by T3, and this mechanism is independent from the endothelium.

Effects of One Resistance Exercise Session on Vascular Smooth Muscle of Hypertensive Rats

International Nuclear Information System (INIS)

Silva, Tharciano Luiz Teixeira Braga da; Mota, Marcelo Mendonça; Fontes, Milene Tavares; Araújo, João Eliakim dos Santos; Carvalho, Vitor Oliveira; Bonjardim, Leonardo Rigoldi; Santos, Márcio Roberto Viana

2015-01-01

Hypertension is a public health problem and increases the incidence of cardiovascular diseases. To evaluate the effects of a resistance exercise session on the contractile and relaxing mechanisms of vascular smooth muscle in mesenteric arteries of N G -nitro L-arginine methyl ester (L-NAME)-induced hypertensive rats. Wistar rats were divided into three groups: control (C), hypertensive (H), and exercised hypertensive (EH). Hypertension was induced by administration of 20 mg/kg of L-NAME for 7 days prior to experimental protocols. The resistance exercise protocol consisted of 10 sets of 10 repetitions and intensity of 40% of one repetition maximum. The reactivity of vascular smooth muscle was evaluated by concentration‑response curves to phenylephrine (PHEN), potassium chloride (KCl) and sodium nitroprusside (SNP). Rats treated with L-NAME showed an increase (p < 0.001) in systolic blood pressure (SBP), diastolic blood pressure (DBP) and mean arterial pressure (MAP) compared to the initial period of induction. No difference in PHEN sensitivity was observed between groups H and EH. Acute resistance exercise reduced (p < 0.001) the contractile response induced by KCl at concentrations of 40 and 60 mM in group EH. Greater (p < 0.01) smooth muscle sensitivity to NPS was observed in group EH as compared to group H. One resistance exercise session reduces the contractile response induced by KCl in addition to increasing the sensitivity of smooth muscle to NO in mesenteric arteries of hypertensive rats

Effects of One Resistance Exercise Session on Vascular Smooth Muscle of Hypertensive Rats

Energy Technology Data Exchange (ETDEWEB)

Silva, Tharciano Luiz Teixeira Braga da; Mota, Marcelo Mendonça; Fontes, Milene Tavares; Araújo, João Eliakim dos Santos; Carvalho, Vitor Oliveira; Bonjardim, Leonardo Rigoldi; Santos, Márcio Roberto Viana, E-mail: marciorvsantos@bol.com.br [Universidade Federal de Sergipe, Universidade de São Paulo (Brazil)

2015-08-15

Hypertension is a public health problem and increases the incidence of cardiovascular diseases. To evaluate the effects of a resistance exercise session on the contractile and relaxing mechanisms of vascular smooth muscle in mesenteric arteries of N{sup G}-nitro L-arginine methyl ester (L-NAME)-induced hypertensive rats. Wistar rats were divided into three groups: control (C), hypertensive (H), and exercised hypertensive (EH). Hypertension was induced by administration of 20 mg/kg of L-NAME for 7 days prior to experimental protocols. The resistance exercise protocol consisted of 10 sets of 10 repetitions and intensity of 40% of one repetition maximum. The reactivity of vascular smooth muscle was evaluated by concentration‑response curves to phenylephrine (PHEN), potassium chloride (KCl) and sodium nitroprusside (SNP). Rats treated with L-NAME showed an increase (p < 0.001) in systolic blood pressure (SBP), diastolic blood pressure (DBP) and mean arterial pressure (MAP) compared to the initial period of induction. No difference in PHEN sensitivity was observed between groups H and EH. Acute resistance exercise reduced (p < 0.001) the contractile response induced by KCl at concentrations of 40 and 60 mM in group EH. Greater (p < 0.01) smooth muscle sensitivity to NPS was observed in group EH as compared to group H. One resistance exercise session reduces the contractile response induced by KCl in addition to increasing the sensitivity of smooth muscle to NO in mesenteric arteries of hypertensive rats.

Effects of One Resistance Exercise Session on Vascular Smooth Muscle of Hypertensive Rats

Directory of Open Access Journals (Sweden)

Tharciano Luiz Teixeira Braga da Silva

2015-01-01

Full Text Available Abstract Background: Hypertension is a public health problem and increases the incidence of cardiovascular diseases. Objective: To evaluate the effects of a resistance exercise session on the contractile and relaxing mechanisms of vascular smooth muscle in mesenteric arteries of NG-nitro L-arginine methyl ester (L-NAME-induced hypertensive rats. Methods: Wistar rats were divided into three groups: control (C, hypertensive (H, and exercised hypertensive (EH. Hypertension was induced by administration of 20 mg/kg of L-NAME for 7 days prior to experimental protocols. The resistance exercise protocol consisted of 10 sets of 10 repetitions and intensity of 40% of one repetition maximum. The reactivity of vascular smooth muscle was evaluated by concentration‑response curves to phenylephrine (PHEN, potassium chloride (KCl and sodium nitroprusside (SNP. Results: Rats treated with L-NAME showed an increase (p < 0.001 in systolic blood pressure (SBP, diastolic blood pressure (DBP and mean arterial pressure (MAP compared to the initial period of induction. No difference in PHEN sensitivity was observed between groups H and EH. Acute resistance exercise reduced (p < 0.001 the contractile response induced by KCl at concentrations of 40 and 60 mM in group EH. Greater (p < 0.01 smooth muscle sensitivity to NPS was observed in group EH as compared to group H. Conclusion: One resistance exercise session reduces the contractile response induced by KCl in addition to increasing the sensitivity of smooth muscle to NO in mesenteric arteries of hypertensive rats.

Epigenetic regulation of vascular smooth muscle cell proliferation and neointima formation by histone deacetylase inhibition.

Science.gov (United States)

Findeisen, Hannes M; Gizard, Florence; Zhao, Yue; Qing, Hua; Heywood, Elizabeth B; Jones, Karrie L; Cohn, Dianne; Bruemmer, Dennis

2011-04-01

Proliferation of smooth muscle cells (SMC) in response to vascular injury is central to neointimal vascular remodeling. There is accumulating evidence that histone acetylation constitutes a major epigenetic modification for the transcriptional control of proliferative gene expression; however, the physiological role of histone acetylation for proliferative vascular disease remains elusive. In the present study, we investigated the role of histone deacetylase (HDAC) inhibition in SMC proliferation and neointimal remodeling. We demonstrate that mitogens induce transcription of HDAC 1, 2, and 3 in SMC. Short interfering RNA-mediated knockdown of either HDAC 1, 2, or 3 and pharmacological inhibition of HDAC prevented mitogen-induced SMC proliferation. The mechanisms underlying this reduction of SMC proliferation by HDAC inhibition involve a growth arrest in the G(1) phase of the cell cycle that is due to an inhibition of retinoblastoma protein phosphorylation. HDAC inhibition resulted in a transcriptional and posttranscriptional regulation of the cyclin-dependent kinase inhibitors p21(Cip1) and p27(Kip). Furthermore, HDAC inhibition repressed mitogen-induced cyclin D1 mRNA expression and cyclin D1 promoter activity. As a result of this differential cell cycle-regulatory gene expression by HDAC inhibition, the retinoblastoma protein retains a transcriptional repression of its downstream target genes required for S phase entry. Finally, we provide evidence that these observations are applicable in vivo by demonstrating that HDAC inhibition decreased neointima formation and expression of cyclin D1 in a murine model of vascular injury. These findings identify HDAC as a critical component of a transcriptional cascade regulating SMC proliferation and suggest that HDAC might play a pivotal role in the development of proliferative vascular diseases, including atherosclerosis and in-stent restenosis.

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

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Biraja C. Dash

2016-07-01

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

Recipient origin of neointimal vascular smooth muscle cells in cardiac allografts with transplant arteriosclerosis

NARCIS (Netherlands)

Hillebrands, JL; van den Hurk, BMH; Klatter, FA; Popa, ER; Nieuwenhuis, P; Rozing, J

2000-01-01

Background: Coronary artery disease is today's most important post-heart transplantation problem after the first perioperative year. Histologically, coronary artery disease is characterized by transplant arteriosclerosis. The current view on this vasculopathy is that vascular smooth muscle (VSM)

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

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Zhongkui Hong

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

Mechanical stretch augments insulin-induced vascular smooth muscle cell proliferation by insulin-like growth factor-1 receptor

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Liu, Gang [Department of Pharmacology, Faculty of Medicine, Kagawa University, Kagawa (Japan); Department of Anesthesiology, First Affiliated Hospital of China Medical University, Shenyang (China); Hitomi, Hirofumi, E-mail: hitomi@kms.ac.jp [Department of Pharmacology, Faculty of Medicine, Kagawa University, Kagawa (Japan); Hosomi, Naohisa [Department of Cardiorenal and Cerebrovascular Medicine, Faculty of Medicine, Kagawa University, Kagawa (Japan); Lei, Bai; Nakano, Daisuke [Department of Pharmacology, Faculty of Medicine, Kagawa University, Kagawa (Japan); Deguchi, Kazushi; Mori, Hirohito; Masaki, Tsutomu [Department of Gastroenterology and Neurology, Faculty of Medicine, Kagawa University, Kagawa (Japan); Ma, Hong [Department of Anesthesiology, First Affiliated Hospital of China Medical University, Shenyang (China); Griendling, Kathy K. [Department of Medicine, Division of Cardiology, Emory University School of Medicine, Atlanta, GA (United States); Nishiyama, Akira [Department of Pharmacology, Faculty of Medicine, Kagawa University, Kagawa (Japan)

2011-10-15

Insulin resistance and hypertension have been implicated in the pathogenesis of cardiovascular disease; however, little is known about the roles of insulin and mechanical force in vascular smooth muscle cell (VSMC) remodeling. We investigated the contribution of mechanical stretch to insulin-induced VSMC proliferation. Thymidine incorporation was stimulated by insulin in stretched VSMCs, but not in un-stretched VSMCs. Insulin increased 2-deoxy-glucose incorporation in both stretched and un-stretched VSMCs. Mechanical stretch augmented insulin-induced extracellular signal-regulated kinase (ERK) and Akt phosphorylation. Inhibitors of epidermal growth factor (EGF) receptor tyrosine kinase and Src attenuated insulin-induced ERK and Akt phosphorylation, as well as thymidine incorporation, whereas 2-deoxy-glucose incorporation was not affected by these inhibitors. Moreover, stretch augmented insulin-like growth factor (IGF)-1 receptor expression, although it did not alter the expression of insulin receptor and insulin receptor substrate-1. Insulin-induced ERK and Akt activation, and thymidine incorporation were inhibited by siRNA for the IGF-1 receptor. Mechanical stretch augments insulin-induced VSMC proliferation via upregulation of IGF-1 receptor, and downstream Src/EGF receptor-mediated ERK and Akt activation. Similar to in vitro experiment, IGF-1 receptor expression was also augmented in hypertensive rats. These results provide a basis for clarifying the molecular mechanisms of vascular remodeling in hypertensive patients with hyperinsulinemia. -- Highlights: {yields} Mechanical stretch augments insulin-induced VSMC proliferation via IGF-1 receptor. {yields} Src/EGFR-mediated ERK and Akt phosphorylation are augmented in stretched VSMCs. {yields} Similar to in vitro experiment, IGF-1 receptor is increased in hypertensive rats. {yields} Results provide possible mechanisms of vascular remodeling in hypertension with DM.

Human induced pluripotent stem cell-derived vascular smooth muscle cells

DEFF Research Database (Denmark)

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

2017-01-01

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

Dynamin-related protein inhibitor downregulates reactive oxygen species levels to indirectly suppress high glucose-induced hyperproliferation of vascular smooth muscle cells

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Maimaitijiang, Alimujiang; Zhuang, Xinyu; Jiang, Xiaofei; Li, Yong, E-mail: 11211220031@fudan.edu.cn

2016-03-18

Hyperproliferation of vascular smooth muscle cells is a pathogenic mechanism common in diabetic vascular complications and is a putatively important therapeutic target. This study investigated multiple levels of biology, including cellular and organellar changes, as well as perturbations in protein synthesis and morphology. Quantitative and qualitative analysis was utilized to assess the effect of mitochondrial dynamic changes and reactive oxygen species(ROS) levels on high-glucose-induced hyperproliferation of vascular smooth muscle cells. The data demonstrated that the mitochondrial fission inhibitor Mdivi-1 and downregulation of ROS levels both effectively inhibited the high-glucose-induced hyperproliferation of vascular smooth muscle cells. Downregulation of ROS levels played a more direct role and ROS levels were also regulated by mitochondrial dynamics. Increased ROS levels induced excessive mitochondrial fission through dynamin-related protein (Drp 1), while Mdivi-1 suppressed the sensitivity of Drp1 to ROS levels, thus inhibiting excessive mitochondrial fission under high-glucose conditions. This study is the first to propose that mitochondrial dynamic changes and ROS levels interact with each other and regulate high-glucose-induced hyperproliferation of vascular smooth muscle cells. This finding provides novel ideas in understanding the pathogenesis of diabetic vascular remodeling and intervention. - Highlights: • Mdivi-1 inhibits VSMC proliferation by lowering ROS level in high-glucose condition. • ROS may be able to induce mitochondrial fission through Drp1 regulation. • Mdivi-1 can suppress the sensitivity of Drp1 to ROS.

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

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

2017-08-25

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

Experimental studies of mitochondrial function in CADASIL vascular smooth muscle cells

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Viitanen, Matti; Sundström, Erik; Baumann, Marc; Poyhonen, Minna; Tikka, Saara; Behbahani, Homira

2013-01-01

Cerebral Autosomal Dominant Arteriopathy with Subcortical Infarcts and Leukoencephalopathy (CADASIL) is a familiar fatal progressive degenerative disorder characterized by cognitive decline, and recurrent stroke in young adults. Pathological features include a dramatic reduction of brain vascular smooth muscle cells and severe arteriopathy with the presence of granular osmophilic material in the arterial walls. Here we have investigated the cellular and mitochondrial function in vascular smooth muscle cell lines (VSMCs) established from CADASIL mutation carriers (R133C) and healthy controls. We found significantly lower proliferation rates in CADASIL VSMC as compared to VSMC from controls. Cultured CADASIL VSMCs were not more vulnerable than control cells to a number of toxic substances. Morphological studies showed reduced mitochondrial connectivity and increased number of mitochondria in CADASIL VSMCs. Transmission electron microscopy analysis demonstrated increased irregular and abnormal mitochondria in CADASIL VSMCs. Measurements of mitochondrial membrane potential (Δψ m ) showed a lower percentage of fully functional mitochondria in CADASIL VSMCs. For a number of genes previously reported to be changed in CADASIL VSMCs, immunoblotting analysis demonstrated a significantly reduced SOD1 expression. These findings suggest that alteration of proliferation and mitochondrial function in CADASIL VSMCs might have an effect on vital cellular functions important for CADASIL pathology. -- Highlights: ► CADASIL is an inherited disease of cerebral vascular cells. ► Mitochondrial dysfunction has been implicated in the pathogenesis of CADASIL. ► Lower proliferation rates in CADASIL VSMC. ► Increased irregular and abnormal mitochondria and lower mitochondrial membrane potential in CADASIL VSMCs. ► Reduced mitochondrial connectivity and increased number of mitochondria in CADASIL VSMCs.

Experimental studies of mitochondrial function in CADASIL vascular smooth muscle cells

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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.

Hypoxic contraction of cultured pulmonary vascular smooth muscle cells

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Murray, T.R.; Chen, L.; Marshall, B.E.; Macarak, E.J.

1990-01-01

The cellular events involved in generating the hypoxic pulmonary vasoconstriction response are not clearly understood, in part because of the multitude of factors that alter pulmonary vascular tone. The goal of the present studies was to determine if a cell culture preparation containing vascular smooth muscle (VSM) cells could be made to contract when exposed to a hypoxic atmosphere. Cultures containing only fetal bovine pulmonary artery VSM cells were assessed for contractile responses to hypoxic stimuli by two methods. In the first, tension forces generated by cells grown on a flexible growth surface (polymerized polydimethyl siloxane) were manifested as wrinkles and distortions of the surface under the cells. Wrinkling of the surface was noted to progressively increase with time as the culture medium bathing the cells was made hypoxic (PO2 approximately 25 mmHg). The changes were sometimes reversible upon return to normoxic conditions and appeared to be enhanced in cells already exhibiting evidence of some baseline tone. Repeated passage in culture did not diminish the hypoxic response. Evidence for contractile responses to hypoxia was also obtained from measurements of myosin light chain (MLC) phosphorylation. Conversion of MLC to the phosphorylated species is an early step in the activation of smooth muscle contraction. Lowering the PO2 in the culture medium to 59 mmHg caused a 45% increase in the proportion of MLC in the phosphorylated form as determined by two-dimensional gel electrophoresis. Similarly, cultures preincubated for 4 h with 32P and then exposed to normoxia or hypoxia for a 5-min experimental period showed more than twice as much of the label in MLCs of the hypoxic cells

Essential role of TGF-beta/Smad pathway on statin dependent vascular smooth muscle cell regulation.

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Juan Rodríguez-Vita

Full Text Available BACKGROUND: The 3-hydroxy-3-methylglutaryl CoA reductase inhibitors (also called statins exert proven beneficial effects on cardiovascular diseases. Recent data suggest a protective role for Transforming Growth Factor-beta (TGF-beta in atherosclerosis by regulating the balance between inflammation and extracellular matrix accumulation. However, there are no studies about the effect of statins on TGF-beta/Smad pathway in atherosclerosis and vascular cells. METHODOLOGY: In cultured vascular smooth muscle cells (VSMCs statins enhanced Smad pathway activation caused by TGF-beta. In addition, statins upregulated TGF-beta receptor type II (TRII, and increased TGF-beta synthesis and TGF-beta/Smad-dependent actions. In this sense, statins, through Smad activation, render VSMCs more susceptible to TGF-beta induced apoptosis and increased TGF-beta-mediated ECM production. It is well documented that high doses of statins induce apoptosis in cultured VSMC in the presence of serum; however the precise mechanism of this effect remains to be elucidated. We have found that statins-induced apoptosis was mediated by TGF-beta/Smad pathway. Finally, we have described that RhoA inhibition is a common intracellular mechanisms involved in statins effects. The in vivo relevance of these findings was assessed in an experimental model of atherosclerosis in apolipoprotein E deficient mice: Treatment with Atorvastatin increased Smad3 phosphorylation and TRII overexpression, associated to elevated ECM deposition in the VSMCs within atheroma plaques, while apoptosis was not detected. CONCLUSIONS: Statins enhance TGF-beta/Smad pathway, regulating ligand levels, receptor, main signaling pathway and cellular responses of VSMC, including apoptosis and ECM accumulation. Our findings show that TGF-beta/Smad pathway is essential for statins-dependent actions in VSMCs.

Vascular Mural Cells Promote Noradrenergic Differentiation of Embryonic Sympathetic Neurons

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Vitor Fortuna

2015-06-01

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

Expression of smooth muscle and non-muscle myosin heavy chain isoforms in cultured vascular smooth muscle cells

International Nuclear Information System (INIS)

Rovner, A.S.; Murphy, R.A.; Owens, G.K.

1986-01-01

Immunocytochemical studies of cultured smooth muscle cells (SMCs) have disagreed on the nature of myosin expression. This investigation was undertaken to test for the presence of heterogeneous myosin heavy chain (MHC) isoforms in cell culture as a possible explanation for these results. Previously, Rovner et al. detected two MHCs in intact smooth muscles which differed in molecular weight by ca. 4000 daltons (SM1 and SM2) using a 3-4% acrylamide gradient SDS gel system. When sub-confluent primary cultures of rat aorta SMCs were assayed by this system, SM1 and SM2 were seen, along with large amounts of a third, unique MHC, NM, which closely resembled the MHC from human platelet in size and antigenicity. Data from 35 S-methionine autoradiograms showed that the log growth phase SMC cultures were producing almost exclusively NM, but the growth arrest, post-confluent cultures synthesized increased relative amounts of the SM MHC forms and contained comparable amounts of SM1, SM2, and NM. The same patterns of MHC synthesis were seen in sub-passaged SMCs. The expression of the SM-specific forms of myosin in quiescent, post-confluent cultures parallels that of smooth muscle actin suggesting that density induced growth arrest promotes cytodifferentiation in cultured vascular SMCs

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

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Hongjing Guan

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

Fibroblast growth factor regulates insulin-like growth factor-binding protein production by vascular smooth muscle cells.

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Ververis, J; Ku, L; Delafontaine, P

1994-02-01

Insulin-like growth factor I is an important mitogen for vascular smooth muscle cells, and its effects are regulated by several binding proteins. Western ligand blotting of conditioned medium from rat aortic smooth muscle cells detected a 24 kDa binding protein and a 28 kDa glycosylated variant of this protein, consistent with insulin-like growth factor binding protein-4 by size. Low amounts of a glycosylated 38 to 42 kDa doublet (consistent with binding protein-3) and a 31 kDa non-glycosylated protein also were present. Basic fibroblast growth factor markedly increased secretion of the 24 kDa binding protein and its 28 kDa glycosylated variant. This effect was dose- and time-dependent and was inhibited by co-incubation with cycloheximide. Crosslinking of [125I]-insulin-like growth factor I to cell monolayers revealed no surface-associated binding proteins, either basally or after agonist treatment. Induction of binding protein production by fibroblast growth factor at sites of vascular injury may be important in vascular proliferative responses in vivo.

RhoA–Rho kinase and Platelet Activating Factor Stimulation of Ovine Fetal Pulmonary Vascular Smooth Muscle Cell Proliferation

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Renteria, Lissette S.; Austin, Monique; Lazaro, Mariecon; Andrews, Mari Ashley; Lustina, Jennessee; Raj, J. Usha; Ibe, Basil O.

2013-01-01

Objectives Platelet Activating Factor (PAF) is produced by pulmonary vascular smooth muscle Cells (PVSMC). We studied effect of Rho kinase on PAF stimulation of PVSMC proliferation in an attempt to understand a role for RhoA/Rho kinase on PAF-induced ovine fetal pulmonary vascular remodeling. Our hypothesis is that PAF acts through Rho kinase, as one of its downstream signaling, to induce arterial (SMC-PA) and venous (SMC-PV) growth in the hypoxic lung environment of the fetus in utero. Materials and methods Rho kinase and MAPK effects on PAF receptor (PAFR)-mediated cell growth and PAFR expression were studied by DNA synthesis, Western and immunocytochemistry. Effects of constructs T19N and G14V on PAF-induced cell proliferation was also studied. Results Hypoxia increased PVSMC proliferation and the Rho kinase inhibitors, Y-27632 and Fasudil (HA-1077) as well as MAPK inhibitors PD 98059 and SB 203580 attenuated PAF stimulation of cell proliferation. RhoA T19N and G14V stimulated cell proliferation, but co-incubation with PAF did not affect proliferative effects of the constructs. PAFR protein expression was significantly down-regulated in both cell types by both Y-27632 and HA-1077 with comparable profiles. Also cells treated with Y-27632 showed less PAF receptor fluorescence with significant disruption of the cell morphology. Conclusions Our results show that Rho kinase nonspecifically modulates PAFR-mediated responses via a translational modification of PAFR protein and suggest that, in vivo, activation of Rho kinase by PAF may be one other pathway to sustain PAFR-mediated PVSMC growth. PMID:24033386

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

Science.gov (United States)

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

2013-10-01

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

Phenotypic modulation of smooth muscle cells during formation of neointimal thickenings following vascular injury.

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Thyberg, J

1998-07-01

Smooth muscle cells build up the media of mammalian arteries and constitute one of the principal cell types in atherosclerotic and restenotic lesions. Accordingly, they show a high degree of plasticity and are able to shift from a differentiated, contractile phenotype to a less differentiated, synthetic phenotype, and then back again. This modulation occurs as a response to vascular injury and includes a prominent structural reorganization with loss of myofilaments and formation of an extensive endoplasmic reticulum and a large Golgi complex. At the same time, the expression of cytoskeletal proteins and other gene products is altered. As a result, the cells lose their contractility and become able to migrate from the media to the intima, proliferate, and secrete extracellular matrix components, thereby contributing to the formation of intimal thickenings. The mechanisms behind this change in morphology and function of the smooth muscle cells are still incompletely understood. A crucial role has been ascribed to basement membrane proteins such as laminin and collagen type IV and adhesive proteins such as fibronectin. A significant role is also played by mitogenic proteins such as platelet-derived growth factor (PDGF) and basic fibroblast growth factor (bFGF). An improved knowledge of the regulation of smooth muscle differentiated properties represents an important part in the search for new methods of prevention and treatment of vascular disease.

Vascular Mural Cells Promote Noradrenergic Differentiation of Embryonic Sympathetic Neurons.

Science.gov (United States)

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

2015-06-23

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

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

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

2014-01-01

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

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

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Yu-Ying Chen

2014-01-01

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

Localization and function of KLF4 in cytoplasm of vascular smooth muscle cell

International Nuclear Information System (INIS)

Liu, Yan; Zheng, Bin; Zhang, Xin-hua; Nie, Chan-juan; Li, Yong-hui; Wen, Jin-kun

2013-01-01

Highlights: •PDGF-BB prompts the translocation of KLF4 to the cytoplasm. •PDGF-BB promotes interaction between KLF4 and actin in the cytoplasm. •Phosphorylation and SUMOylation of KLF4 participates in regulation of cytoskeletal organization. •KLF4 regulates cytoskeleton by promoting the expression of contraction-associated genes. -- Abstract: The Krüppel-like factor 4 is a DNA-binding transcriptional regulator that regulates a diverse array of cellular processes, including development, differentiation, proliferation, and apoptosis. The previous studies about KLF4 functions mainly focused on its role as a transcription factor, its functions in the cytoplasm are still unknown. In this study, we found that PDGF-BB could prompt the translocation of KLF4 to the cytoplasm through CRM1-mediated nuclear export pathway in vascular smooth muscle cells (VSMCs) and increased the interaction of KLF4 with actin in the cytoplasm. Further study showed that both KLF4 phosphorylation and SUMOylation induced by PDGF-BB participates in regulation of cytoskeletal organization by stabilizing the actin cytoskeleton in VSMCs. In conclusion, these results identify that KLF4 participates in the cytoskeletal organization by stabilizing cytoskeleton in the cytoplasm of VSMCs

Localization and function of KLF4 in cytoplasm of vascular smooth muscle cell

Energy Technology Data Exchange (ETDEWEB)

Liu, Yan [Department of Biochemistry and Molecular Biology, The Key Laboratory of Neurobiology and Vascular Biology (China); The Third Hospital of Hebei Medical University, Shijazhuang (China); Zheng, Bin; Zhang, Xin-hua; Nie, Chan-juan; Li, Yong-hui [Department of Biochemistry and Molecular Biology, The Key Laboratory of Neurobiology and Vascular Biology (China); Wen, Jin-kun, E-mail: wjk@hebmu.edu.cn [Department of Biochemistry and Molecular Biology, The Key Laboratory of Neurobiology and Vascular Biology (China)

2013-06-28

Highlights: •PDGF-BB prompts the translocation of KLF4 to the cytoplasm. •PDGF-BB promotes interaction between KLF4 and actin in the cytoplasm. •Phosphorylation and SUMOylation of KLF4 participates in regulation of cytoskeletal organization. •KLF4 regulates cytoskeleton by promoting the expression of contraction-associated genes. -- Abstract: The Krüppel-like factor 4 is a DNA-binding transcriptional regulator that regulates a diverse array of cellular processes, including development, differentiation, proliferation, and apoptosis. The previous studies about KLF4 functions mainly focused on its role as a transcription factor, its functions in the cytoplasm are still unknown. In this study, we found that PDGF-BB could prompt the translocation of KLF4 to the cytoplasm through CRM1-mediated nuclear export pathway in vascular smooth muscle cells (VSMCs) and increased the interaction of KLF4 with actin in the cytoplasm. Further study showed that both KLF4 phosphorylation and SUMOylation induced by PDGF-BB participates in regulation of cytoskeletal organization by stabilizing the actin cytoskeleton in VSMCs. In conclusion, these results identify that KLF4 participates in the cytoskeletal organization by stabilizing cytoskeleton in the cytoplasm of VSMCs.

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

NARCIS (Netherlands)

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

2011-01-01

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

Influence of 103Pd radioactive stent on apoptosis of vascular smooth muscle cells

International Nuclear Information System (INIS)

Liu Yingmei; Wu Wei; Chen Xiaochao; Zhang Xuming; Wang Jingfeng; Wei Yulin; Yang Li

2003-01-01

Objective: To evaluate the influence of 103 Pd 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 103 Pd radioactive stent for preventing restenosis after angioplasty. Methods: Fifty male New Zealand rabbits were randomized into stent group and 103 Pd 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 103 Pd stent group was less than that of stent group. It was most obvious at the 56th day (P 103 Pd 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)% (P 103 Pd 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)% (P 103 Pd 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 103 Pd 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 (P 103 Pd 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

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

International Nuclear Information System (INIS)

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

2006-01-01

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

The Smooth Muscle of the Artery

Science.gov (United States)

1975-01-01

of vascular smooth muscle are contrac- tion, thereby mediating vaso constriction, and the synthesis of the extracellular proteins and polysaccharides ...of the monosaccharides turned out to be different for instance from cornea to aorta (229, 283). In the conditions yed (4 hours incubation at 37 degrees... polysaccharides only. This glyco- protein is not very rich in sugar components (- 5Z) (228, 284), but is a very acidic protein (286). Fig.66 shows

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.

Control of Vascular Smooth Muscle Cell Growth by Connexin 43

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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.

Expression of lectin-like oxidized LDL receptor-1 in smooth muscle cells after vascular injury

International Nuclear Information System (INIS)

Eto, Hideyuki; Miyata, Masaaki; Kume, Noriaki; Minami, Manabu; Itabe, Hiroyuki; Orihara, Koji; Hamasaki, Shuichi; Biro, Sadatoshi; Otsuji, Yutaka; Kita, Toru; Tei, Chuwa

2006-01-01

Lectin-like oxidized LDL receptor-1 (LOX-1) is an oxidized LDL receptor, and its role in restenosis after angioplasty remains unknown. We used a balloon-injury model of rabbit aorta, and reverse transcription-polymerase chain reaction revealed that LOX-1 mRNA expression was modest in the non-injured aorta, reached a peak level 2 days after injury, and remained elevated until 24 weeks after injury. Immunohistochemistry and in situ hybridization showed that LOX-1 was not detected in the media of non-injured aorta but expressed in both medial and neointimal smooth muscle cells (SMC) at 2 and 24 weeks after injury. Low concentrations of ox-LDL (10 μg/mL) stimulated the cultured SMC proliferation, which was inhibited by antisense oligonucleotides of LOX-1 mRNA. Double immunofluorescense staining showed the colocalization of LOX-1 and proliferating cell nuclear antigen in human restenotic lesion. These results suggest that LOX-1 mediates ox-LDL-induced SMC proliferation and plays a role in neointimal formation after vascular injury

The endothelial αENaC contributes to vascular endothelial function in vivo

DEFF Research Database (Denmark)

Tarjus, Antoine; Maase, Martina; Jeggle, Pia

2017-01-01

The Epithelial Sodium Channel (ENaC) is a key player in renal sodium homeostasis. The expression of α β γ ENaC subunits has also been described in the endothelium and vascular smooth muscle, suggesting a role in vascular function. We recently demonstrated that endothelial ENaC is involved in aldo......-mediated dilation. Our data suggest that endothelial αENaC contributes to vascular endothelial function in vivo....

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

Science.gov (United States)

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

1996-03-01

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

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...

Peptides PHI and VIP: comparison between vascular and nonvascular smooth muscle effect in rabbit uterus

International Nuclear Information System (INIS)

Bardrum, B.; Ottesen, B.; Fahrenkrug, J.

1986-01-01

The distribution and effects of the two neuropeptides, vasoactive intestinal polypeptide (VIP) and peptide histidine isoleucine amide (PHI), on vascular and nonvascular smooth muscle in the urogenital tract of nonpregnant rabbit female, were investigated. Immunoreactive VIP and PHI were present in all regions except the ovary with the highest concentration in the uterin cervix. By using in vitro tension recordings of myometrial specimens, it was demonstrated that both peptides displayed a dose-dependent inhibition of the mechanical activity. The dose-response curves of VIP and PHI were superimposable with and ID 50 of 3 x 10 -8 mol/l, and their combined effect was additive. In addition, the influence of the two peptides on myometrial blood flow (MBF) was investigated by the xenon-133 washout technique. Both peptides were found to increase MBF with the same potency and efficacy. Their combined effect was additive. In conclusion VIP and PHI are present in the rabbit urogenital tract, and the two peptides are equipotent inhibitors of mechanical nonvascular and vascular smooth muscle activity in the uterus

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

Science.gov (United States)

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

2012-01-01

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

Vascular smooth muscle cells express the alpha(1A) subunit of a P-/Q-type voltage-dependent Ca(2+)Channel, and It is functionally important in renal afferent arterioles

DEFF Research Database (Denmark)

Hansen, Pernille B. Lærkegaard; Jensen, Boye L.; Andreasen, D

2000-01-01

In the present study, we tested whether the alpha(1A) subunit, which encodes a neuronal isoform of voltage-dependent Ca(2+) channels (VDCCs) (P-/Q-type), was present and functional in vascular smooth muscle and renal resistance vessels. By reverse transcription-polymerase chain reaction...... preglomerular resistance vessels and aorta, as well as mesangial cells, and that P-type VDCCs contribute to Ca(2+) influx in aortic and renal VSMCs and are involved in depolarization-mediated contraction in renal afferent arterioles....

Regulation of capacitative and non-capacitative Ca2+ entry in A7r5 vascular smooth muscle cells

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COLIN W TAYLOR

2004-01-01

Full Text Available A capacitative Ca2+ entry (CCE pathway, activated by depletion of intracellular Ca2+ stores, is thought to mediate much of the Ca2+ entry evoked by receptors that stimulate phospholipase C (PLC. However, in A7r5 vascular smooth muscle cells, vasopressin, which stimulates PLC, empties intracellular Ca2+ stores but simultaneously inhibits their ability to activate CCE. The diacylglycerol produced with the IP3 that empties the stores is metabolized to arachidonic and this leads to activation of nitric oxide (NO synthase, production of NO and cyclic GMP, and consequent activation of protein kinase G. The latter inhibits CCE. In parallel, NO directly activates a non-capacitative Ca2+ entry (NCCE pathway, which is entirely responsible for the Ca2+ entry that occurs in the presence of vasopressin. This reciprocal regulation of two Ca2+ entry pathways ensures that there is sequential activation of first NCCE in the presence of vasopressin, and then a transient activation of CCE when vasopressin is removed. We suggest that the two routes for Ca2+ entry may selectively direct Ca2+ to processes that mediate activation and then recovery of the cell.

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

International Nuclear Information System (INIS)

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

2012-01-01

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

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

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Chang Hyun Byon

2016-10-01

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

Resveratrol prevents angiotensin II-induced hypertrophy of vascular smooth muscle cells through the transactivation of growth factor receptors.

Science.gov (United States)

Hossain, Ekhtear; Anand-Srivastava, Madhu B

2017-08-01

We previously showed that augmented levels of endogenous angiotensin II (AngII) contribute to vascular smooth muscle cell (VSMC) hypertrophy through the transactivation of growth factor receptors in spontaneously hypertensive rats. Resveratrol (RV), a polyphenolic component of red wine, has also been shown to attenuate AngII-evoked VSMC hypertrophy; however, the molecular mechanism mediating this response is obscure. The present study was therefore undertaken to examine whether RV could prevent AngII-induced VSMC hypertrophy through the transactivation of growth factor receptor and associated signaling pathways. AngII treatment of VSMC enhanced the protein synthesis that was attenuated towards control levels by RV pretreatment as well as by the inhibitors of NADPH oxidase, c-Src, and growth factor receptors. Furthermore, RV pretreatment also inhibited enhanced levels of superoxide anion, NADPH oxidase activity, increased expression of NADPH oxidase subunits, and phosphorylation of c-Src, EGF-R, PDGE-R, ERK1/2, and AKT1/2. In conclusion, these results indicate that RV attenuates AngII-induced VSMC hypertrophy through the inhibition of enhanced oxidative stress and activation of c-Src, growth factor receptors, and MAPK/AKT signaling. We suggest that RV could be used as a therapeutic agent in the treatment of vascular complications associated with hypertension and hypertrophy.

Major vault protein in cardiac and smooth muscle.

Science.gov (United States)

Shults, Nataliia V; Das, Dividutta; Suzuki, Yuichiro J

Major vault protein (MVP) is the major component of the vault particle whose functions are not well understood. One proposed function of the vault is to serve as a mechanism of drug transport, which confers drug resistance in cancer cells. We show that MVP can be found in cardiac and smooth muscle. In human airway smooth muscle cells, knocking down MVP was found to cause cell death, suggesting that MVP serves as a cell survival factor. Further, our laboratory found that MVP is S-glutathionylated in response to ligand/receptor-mediated cell signaling. The S-glutathionylation of MVP appears to regulate protein-protein interactions between MVP and a protein called myosin heavy chain 9 (MYH9). Through MYH9 and Vsp34, MVP may form a complex with Beclin-1 that regulates autophagic cell death. In pulmonary vascular smooth muscle, proteasome inhibition promotes the ubiquitination of MVP, which may function as a mechanism of proteasome inhibition-mediated cell death. Investigating the functions and the regulatory mechanisms of MVP and vault particles is an exciting new area of research in cardiovascular/pulmonary pathophysiology.

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

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Ekatherina Stoyanova

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

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

Science.gov (United States)

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

2014-01-01

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

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

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

Energy Technology Data Exchange (ETDEWEB)

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

2016-08-15

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

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

International Nuclear Information System (INIS)

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

2016-01-01

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

Biomarkers of drug-induced vascular injury

International Nuclear Information System (INIS)

Brott, D.; Gould, S.; Jones, H.; Schofield, J.; Prior, H.; Valentin, J.P; Bjurstrom, S.; Kenne, K.; Schuppe-Koistinen, I.; Katein, A.; Foster-Brown, L.; Betton, G.; Richardson, R.; Evans, G.; Louden, C.

2005-01-01

In pre-clinical safety studies, drug-induced vascular injury is an issue of concern because there are no obvious diagnostic markers for pre-clinical or clinical monitoring and there is an intellectual gap in our understanding of the pathogenesis of this lesion. While vasodilatation and increased shear stress appear to play a role, the exact mechanism(s) of injury to the primary targets, smooth muscle and endothelial cells are unknown. However, evaluation of novel markers for potential clinical monitoring with a mechanistic underpinning would add value in risk assessment and management. This mini review focuses on the progress to identify diagnostic markers of drug-induced vascular injury. Von Willebrand factor (vWF), released upon perturbation of endothelial cells, is transiently increased in plasma prior to morphological evidence of damage in dogs or rats treated with vascular toxicants. Therefore, vWF might be a predictive biomarker of vascular injury. However, vWF is not an appropriate biomarker of lesion progression or severity since levels return to baseline values when there is morphological evidence of injury. A potential mechanistically linked biomarker of vascular injury is caveolin-1. Expression of this protein, localized primarily to smooth muscle and endothelial cells, decreases with the onset of vascular damage. Since vascular injury involves multiple mediators and cell types, evaluation of a panel rather than a single biomarker may be more useful in monitoring early and severe progressive vascular injury

Effects of gamma rays on rat vascular smooth muscle fibers

Energy Technology Data Exchange (ETDEWEB)

Ghassan, A [Radio-Biology and Health Dept. Syrian Atomic Energy Commission, (Syrian Arab Republic)

1995-10-01

Modifications of the Vasomotoricity induced by gamma rays have been investigated. Vascular smooth muscle fibres (VSMF) of rat portal vein have been used in this study. Irradiation procedures using a {sup 60} Co source have been carried out as follows: - Whole body irradiation. - Irradiation of isolated portal vein and isolated VSMF. Our results show that : 1-irradiation reduces the functional competition between Mg{sup 2+} and Ca{sup 2+}, thus hyper magnetic Krebs solutions have a negligible effect on irradiated VSMF. 2- irradiation activates Ca{sup 2+} influx into the VSMF. Thus the effect of hypocalcemic solutions on irradiated VSMF is minor compared with control. 3- Hyperpotassic solutions provoke titanic contractions with high amplitude on the irradiated VSMF compared with control. 5 figs.

Brain cytoplasmic RNA 1 suppresses smooth muscle differentiation and vascular development in mice.

Science.gov (United States)

Wang, Yung-Chun; Chuang, Ya-Hui; Shao, Qiang; Chen, Jian-Fu; Chen, Shi-You

2018-04-13

The cardiovascular system develops during the early stages of embryogenesis, and differentiation of smooth muscle cells (SMCs) is essential for that process. SMC differentiation is critically regulated by transforming growth factor (TGF)-β/SMAD family member 3 (SMAD3) signaling, but other regulators may also play a role. For example, long noncoding RNAs (lncRNAs) regulate various cellular activities and events, such as proliferation, differentiation, and apoptosis. However, whether long noncoding RNAs also regulate SMC differentiation remains largely unknown. Here, using the murine cell line C3H10T1/2, we found that brain cytoplasmic RNA 1 (BC1) is an important regulator of SMC differentiation. BC1 overexpression suppressed, whereas BC1 knockdown promoted, TGF-β-induced SMC differentiation, as indicated by altered cell morphology and expression of multiple SMC markers, including smooth muscle α-actin (αSMA), calponin, and smooth muscle 22α (SM22α). BC1 appeared to block SMAD3 activity and inhibit SMC marker gene transcription. Mechanistically, BC1 bound to SMAD3 via RNA SMAD-binding elements (rSBEs) and thus impeded TGF-β-induced SMAD3 translocation to the nucleus. This prevented SMAD3 from binding to SBEs in SMC marker gene promoters, an essential event in SMC marker transcription. In vivo , BC1 overexpression in mouse embryos impaired vascular SMC differentiation, leading to structural defects in the artery wall, such as random breaks in the elastic lamina, abnormal collagen deposition on SM fibers, and disorganized extracellular matrix proteins in the media of the neonatal aorta. Our results suggest that BC1 is a suppressor of SMC differentiation during vascular development. © 2018 by The American Society for Biochemistry and Molecular Biology, Inc.

Andrographolide induces vascular smooth muscle cell apoptosis through a SHP-1-PP2A-p38MAPK-p53 cascade.

Science.gov (United States)

Chen, Yu-Ying; Hsieh, Cheng-Ying; Jayakumar, Thanasekaran; Lin, Kuan-Hung; Chou, Duen-Suey; Lu, Wan-Jung; Hsu, Ming-Jen; Sheu, Joen-Rong

2014-07-10

The abnormal growth of vascular smooth muscle cells (VSMCs) is considered a critical pathogenic process in inflammatory vascular diseases. We have previously demonstrated that protein phosphatase 2 A (PP2A)-mediated NF-κB dephosphorylation contributes to the anti-inflammatory properties of andrographolide, a novel NF-κB inhibitor. In this study, we investigated whether andrographolide causes apoptosis, and characterized its apoptotic mechanisms in rat VSMCs. Andrographolide activated the p38 mitogen-activated protein kinase (p38MAPK), leading to p53 phosphorylation. Phosphorylated p53 subsequently transactivated the expression of Bax, a pro-apoptotic protein. Transfection with pp2a small interfering RNA (siRNA) suppressed andrographolide-induced p38MAPK activation, p53 phosphorylation, and caspase 3 activation. Andrographolide also activated the Src homology 1 domain-containing protein tyrosine phosphatase (SHP-1), and induced PP2A dephosphorylation, both of which were inhibited by the SHP-1 inhibitor sodium stibogluconate (SSG) or shp-1 siRNA. SSG or shp-1 siRNA prevented andrographolide-induced apoptosis. These results suggest that andrographolide activates the PP2A-p38MAPK-p53-Bax cascade, causing mitochondrial dysfunction and VSMC death through an SHP-1-dependent mechanism.

Suppressive effects of lysozyme on polyphosphate-mediated vascular inflammatory responses

Energy Technology Data Exchange (ETDEWEB)

Chung, Jiwoo [College of Pharmacy, CMRI, Research Institute of Pharmaceutical Sciences, BK21 Plus KNU Multi-Omics Based Creative Drug Research Team, Kyungpook National University, Daegu 41566 (Korea, Republic of); Ku, Sae-Kwang [Department of Anatomy and Histology, College of Korean Medicine, Daegu Haany University, Gyeongsan 38610 (Korea, Republic of); Lee, Suyeon [College of Pharmacy, CMRI, Research Institute of Pharmaceutical Sciences, BK21 Plus KNU Multi-Omics Based Creative Drug Research Team, Kyungpook National University, Daegu 41566 (Korea, Republic of); Bae, Jong-Sup, E-mail: baejs@knu.ac.kr [College of Pharmacy, CMRI, Research Institute of Pharmaceutical Sciences, BK21 Plus KNU Multi-Omics Based Creative Drug Research Team, Kyungpook National University, Daegu 41566 (Korea, Republic of)

2016-06-10

Lysozyme, found in relatively high concentration in blood, saliva, tears, and milk, protects us from the ever-present danger of bacterial infection. Previous studies have reported proinflammatory responses of endothelial cells to the release of polyphosphate(PolyP). In this study, we examined the anti-inflammatory responses and mechanisms of lysozyme and its effects on PolyP-induced septic activities in human umbilical vein endothelial cells (HUVECs) and mice. The survival rates, septic biomarker levels, behavior of human neutrophils, and vascular permeability were determined in PolyP-activated HUVECs and mice. Lysozyme suppressed the PolyP-mediated vascular barrier permeability, upregulation of inflammatory biomarkers, adhesion/migration of leukocytes, and activation and/or production of nuclear factor-κB, tumor necrosis factor-α, and interleukin-6. Furthermore, lysozyme demonstrated protective effects on PolyP-mediated lethal death and the levels of the related septic biomarkers. Therefore, these results indicated the therapeutic potential of lysozyme on various systemic inflammatory diseases, such as sepsis or septic shock. -- Highlights: •PolyP is shown to be an important mediator of vascular inflammation. •Lysozyme inhibited PolyP-mediated hyperpermeability. •Lysozyme inhibited PolyP-mediated septic response. •Lysozyme reduced PolyP-induced septic mortality.

Suppressive effects of lysozyme on polyphosphate-mediated vascular inflammatory responses

International Nuclear Information System (INIS)

Chung, Jiwoo; Ku, Sae-Kwang; Lee, Suyeon; Bae, Jong-Sup

2016-01-01

Lysozyme, found in relatively high concentration in blood, saliva, tears, and milk, protects us from the ever-present danger of bacterial infection. Previous studies have reported proinflammatory responses of endothelial cells to the release of polyphosphate(PolyP). In this study, we examined the anti-inflammatory responses and mechanisms of lysozyme and its effects on PolyP-induced septic activities in human umbilical vein endothelial cells (HUVECs) and mice. The survival rates, septic biomarker levels, behavior of human neutrophils, and vascular permeability were determined in PolyP-activated HUVECs and mice. Lysozyme suppressed the PolyP-mediated vascular barrier permeability, upregulation of inflammatory biomarkers, adhesion/migration of leukocytes, and activation and/or production of nuclear factor-κB, tumor necrosis factor-α, and interleukin-6. Furthermore, lysozyme demonstrated protective effects on PolyP-mediated lethal death and the levels of the related septic biomarkers. Therefore, these results indicated the therapeutic potential of lysozyme on various systemic inflammatory diseases, such as sepsis or septic shock. -- Highlights: •PolyP is shown to be an important mediator of vascular inflammation. •Lysozyme inhibited PolyP-mediated hyperpermeability. •Lysozyme inhibited PolyP-mediated septic response. •Lysozyme reduced PolyP-induced septic mortality.

Vascular wall-resident CD44+ multipotent stem cells give rise to pericytes and smooth muscle cells and contribute to new vessel maturation.

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Diana Klein

Full Text Available Here, we identify CD44(+CD90(+CD73(+CD34(-CD45(- cells within the adult human arterial adventitia with properties of multipotency which were named vascular wall-resident multipotent stem cells (VW-MPSCs. VW-MPSCs exhibit typical mesenchymal stem cell characteristics including cell surface markers in immunostaining and flow cytometric analyses, and differentiation into adipocytes, chondrocytes and osteocytes under culture conditions. Particularly, TGFß1 stimulation up-regulates smooth muscle cell markers in VW-MPSCs. Using fluorescent cell labelling and co-localisation studies we show that VW-MPSCs differentiate to pericytes/smooth muscle cells which cover the wall of newly formed endothelial capillary-like structures in vitro. Co-implantation of EGFP-labelled VW-MPSCs and human umbilical vein endothelial cells into SCID mice subcutaneously via Matrigel results in new vessels formation which were covered by pericyte- or smooth muscle-like cells generated from implanted VW-MPSCs. Our results suggest that VW-MPSCs are of relevance for vascular morphogenesis, repair and self-renewal of vascular wall cells and for local capacity of neovascularization in disease processes.

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

NARCIS (Netherlands)

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

2009-01-01

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

Tungstate-Targeting of BKαβ1 Channels Tunes ERK Phosphorylation and Cell Proliferation in Human Vascular Smooth Muscle

OpenAIRE

López López, José Ramón; Fernández Mariño, Ana Isabel; Cidad, Pilar; Zafra, Delia; Nocito, Laura; Domínguez, Jorge; Oliván Viguera, Aida; Köhler, Ralf; Pérez García, María Teresa; Valverde, Miguel Ángel; Guinovart, Joan J.; Fernández Fernández, José Manuel

2015-01-01

Producción Científica Despite the substantial knowledge on the antidiabetic, antiobesity and antihypertensive actions of tungstate, information on its primary target/s is scarce. Tungstate activates both the ERK1/2 pathway and the vascular voltage- and Ca2+-dependent large-conductance BKαβ1 potassium channel, which modulates vascular smooth muscle cell (VSMC) proliferation and function, respectively. Here, we have assessed the possible involvement of BKαβ1 channels in the tungstate-induced...

CCN5 modulates the antiproliferative effect of heparin and regulates cell motility in vascular smooth muscle cells

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Castellot John J

2003-11-01

Full Text Available Abstract Background Vascular smooth muscle cell (VSMC hyperplasia plays an important role in both chronic and acute vascular pathologies including atherosclerosis and restenosis. Considerable work has focused on the mechanisms regulating VSMC proliferation and motility. Earlier work in our lab revealed a novel growth arrest-specific (gas gene induced in VSMC exposed to the antiproliferative agent heparin. This gene is a member of the CCN family and has been given the name CCN5. The objective of the present study is to elucidate the function of CCN5 protein and to explore its mechanism of action in VSMC. Results Using RNA interference (RNAi, we first demonstrate that CCN5 is required for the antiproliferative effect of heparin in VSMC. We also use this gene knockdown approach to show that CCN5 is an important negative regulator of motility. To explore the mechanism of action of CCN5 on VSMC motility, we use RNAi to demonstrate that knock down of CCN5 up regulates expression of matrix metalloproteinase-2 (MMP-2, an important stimulator of motility in VSMC. In addition, forced expression of CCN5 via adenovirus results in reduced MMP-2 activity, this also corroborates the gene knock down results. Finally, we show that loss of CCN5 expression in VSMC causes changes in VSMC morphology and cytoskeletal organization, including a reduction in the amount and macromolecular assembly of smooth muscle cell α-actin. Conclusions This work provides important new insights into the regulation of smooth muscle cell proliferation and motility by CCN5 and may aid the development of therapies for vascular diseases.

PDGF activates K-Cl cotransport through phosphoinositide 3-kinase and protein phosphatase-1 in primary cultures of vascular smooth muscle cells.

Science.gov (United States)

Zhang, Jing; Lauf, Peter K; Adragna, Norma C

2005-07-15

K-Cl cotransport (K-Cl COT, KCC) is an electroneutrally coupled movement of K and Cl present in most cells. In this work, we studied the pathways of regulation of K-Cl COT by platelet-derived growth factor (PDGF) in primary cultures of vascular smooth muscle cells (VSMCs). Wortmannin and LY 294002 blocked the PDGF-induced K-Cl COT activation, indicating that the phosphoinositide 3-kinase (PI 3-K) pathway is involved. However, PD 98059 had no effect on K-Cl COT activation by PDGF, suggesting that the mitogen-activated protein kinase pathway is not involved under the experimental conditions tested. Involvement of phosphatases was also examined. Sodium orthovanadate, cyclosporin A and okadaic acid had no effect on PDGF-stimulated K-Cl COT. Calyculin A blocked the PDGF-stimulated K-Cl COT by 60%, suggesting that protein phosphatase-1 (PP-1) is a mediator in the PDGF signaling pathway/s. In conclusion, our results indicate that the PDGF-mediated pathways of K-Cl COT regulation involve the signaling molecules PI 3-K and PP-1.

Antibodies against AT1 receptors are associated with vascular endothelial and smooth muscle function impairment: protective effects of hydroxysafflor yellow A.

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Zhu Jin

Full Text Available Ample evidence has shown that autoantibodies against AT1 receptors (AT1-AA are closely associated with human cardiovascular disease. The aim of this study was to investigate mechanisms underlying AT1-AA-induced vascular structural and functional impairments in the formation of hypertension, and explore ways for preventive treatment. We used synthetic peptide corresponding to the sequence of the second extracellular loop of the AT1 receptor (165-191 to immunize rats and establish an active immunization model. Part of the model received preventive therapy by losartan (20 mg/kg/day and hyroxysafflor yellow A (HSYA (10 mg/kg/day. The result show that systolic blood pressure (SBP and heart rate (HR of immunized rats was significantly higher, and closely correlated with the plasma AT1-Ab titer. The systolic response of thoracic aortic was increased, but diastolic effects were attenuated markedly. Histological observation showed that the thoracic aortic endothelium of the immunized rats became thinner or ruptured, inflammatory cell infiltration, medial smooth muscle cell proliferation and migration, the vascular wall became thicker. There was no significant difference in serum antibody titer between losartan and HSYA groups and the immunized group. The vascular structure and function were reversed, and plasma biochemical parameters were also improved significantly in the two treatment groups. These results suggest that AT1-Ab could induce injury to vascular endothelial cells, and proliferation of smooth muscle cells. These changes were involved in the formation of hypertension. Treatment with AT1 receptor antagonists and anti oxidative therapy could block the pathogenic effect of AT1-Ab on vascular endothelial and smooth muscle cells.

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

Energy Technology Data Exchange (ETDEWEB)

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

2012-03-30

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

Effect of lovastatin on rabbit vascular smooth muscle cells

International Nuclear Information System (INIS)

Luan Zhaoxia; Pei Zhuguo

2003-01-01

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- 32 P]-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

Hsc70 regulates cell surface ASIC2 expression and vascular smooth muscle cell migration.

Science.gov (United States)

Grifoni, Samira C; McKey, Susan E; Drummond, Heather A

2008-05-01

Recent studies suggest members of the degenerin (DEG)/epithelial Na(+) channel (ENaC)/acid-sensing ion channel (ASIC) protein family play an important role in vascular smooth muscle cell (VSMC) migration. In a previous investigation, we found suppression of a certain DEG/ENaC/ASIC member, ASIC2, increased VSMC chemotactic migration, raising the possibility that ASIC2 may play an inhibitory role. Because ASIC2 protein was retained in the cytoplasm, we reasoned increasing surface expression of ASIC2 might unmask the inhibitory role of ASIC2 in VSMC migration so we could test the hypothesis that ASIC2 inhibits VSMC migration. Therefore, we used the chemical chaperone glycerol to enhance ASIC2 expression. Glycerol 1) increased cytoplasm ASIC2 expression, 2) permitted detection of ASIC2 at the cell surface, and 3) inhibited platelet-derived growth factor (PDGF)-bb mediated VSMC migration. Furthermore, ASIC2 silencing completely abolished the inhibitory effect of glycerol on migration, suggesting upregulation of ASIC2 is responsible for glycerol-induced inhibition of VSMC migration. Because other investigators have shown that glycerol regulates ENaC/ASIC via interactions with a certain heat shock protein, heat shock protein 70 (Hsc70), we wanted to determine the importance of Hsc70 on ASIC2 expression in VSMCs. We found that Hsc70 silencing increases ASIC2 cell surface expression and inhibits VSMC migration, which is abolished by cosilencing ASIC2. These data demonstrate that Hsc70 inhibits ASIC2 expression, and, when the inhibitory effect of Hsc70 is removed, ASIC2 expression increases, resulting in reduced VSMC migration. Because VSMC migration contributes to vasculogenesis and remodeling following vascular injury, our findings raise the possibility that ASIC2-Hsc70 interactions may play a role in these processes.

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

Energy Technology Data Exchange (ETDEWEB)

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

2010-04-02

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

Novel Mechanism of Plasma Prekallikrein (PK) Activation by Vascular Smooth Muscle Cells: Evidence of the presence of PK Activator

OpenAIRE

Keum, Joo-Seob; Jaffa, Miran A; Luttrell, Louis M; Jaffa, Ayad A.

2014-01-01

The contribution of plasma prekallikrein (PK) to vascular remodeling is becoming increasingly recognized. Plasma PK is activated when the zymogen PK is digested to an active enzyme by activated factor XII (FXII). Here, we present our findings that vascular smooth muscle cells (VSMC) activate plasma PK in the absence of FXII. Extracted plasma membrane and cytosolic fractions of VSMCs activate PK, but the rate of PK activation was greater by the membrane fraction. FXII neutralizing antibody did...

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

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Ming Zhang

2014-01-01

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

Statins meditate anti-atherosclerotic action in smooth muscle cells by peroxisome proliferator-activated receptor-γ activation

International Nuclear Information System (INIS)

Fukuda, Kazuki; Matsumura, Takeshi; Senokuchi, Takafumi; Ishii, Norio; Kinoshita, Hiroyuki; Yamada, Sarie; Murakami, Saiko; Nakao, Saya; Motoshima, Hiroyuki; Kondo, Tatsuya; Kukidome, Daisuke; Kawasaki, Shuji; Kawada, Teruo; Nishikawa, Takeshi; Araki, Eiichi

2015-01-01

Highlights: • Statins induce PPARγ activation in vascular smooth muscle cells. • Statin-induced PPARγ activation is mediated by COX-2 expression. • Statins suppress cell migration and proliferation in vascular smooth muscle cells. • Statins inhibit LPS-induced inflammatory responses by PPARγ activation. • Fluvastatin suppress the progression of atherosclerosis and induces PPARγ activation in the aorta of apoE-deficient mice. - Abstract: The peroxisome proliferator-activated receptor-γ (PPARγ) is an important regulator of lipid and glucose metabolism, and its activation is reported to suppress the progression of atherosclerosis. We have reported that 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (statins) activate PPARγ in macrophages. However, it is not yet known whether statins activate PPARγ in other vascular cells. In the present study, we investigated whether statins activate PPARγ in smooth muscle cells (SMCs) and endothelial cells (ECs) and thus mediate anti-atherosclerotic effects. Human aortic SMCs (HASMCs) and human umbilical vein ECs (HUVECs) were used in this study. Fluvastatin and pitavastatin activated PPARγ in HASMCs, but not in HUVECs. Statins induced cyclooxygenase-2 (COX-2) expression in HASMCs, but not in HUVECs. Moreover, treatment with COX-2-siRNA abrogated statin-mediated PPARγ activation in HASMCs. Statins suppressed migration and proliferation of HASMCs, and inhibited lipopolysaccharide-induced expression of monocyte chemoattractant protein-1 (MCP-1) and tumor necrosis factor-α (TNF-α) in HASMCs. These effects of statins were abrogated by treatment with PPARγ-siRNA. Treatment with statins suppressed atherosclerotic lesion formation in Apoe −/− mice. In addition, transcriptional activity of PPARγ and CD36 expression were increased, and the expression of MCP-1 and TNF-α was decreased, in the aorta of statin-treated Apoe −/− mice. In conclusion, statins mediate anti-atherogenic effects through PPAR�

Small GTP-Binding Protein Rac Is an Essential Mediator of Vascular Endothelial Growth Factor-Induced Endothelial Fenestrations and Vascular Permeability

DEFF Research Database (Denmark)

Eriksson, A.; Cao, R.; Tritsaris, K.

2003-01-01

fenestrated endothelium, a feature linked with increased vascular permeability. A cell-permeable Rac antagonist (TAT-RacN17) converted VEGF-induced, leaky vascular plexuses into well-defined vascular networks. In addition, this Rac mutant blocked formation of VEGF-induced endothelial fenestrations...... in mediation of VEGF-induced vascular permeability but less so in neovascularization. This may have conceptual implications for applying Rac antagonists in treatment and prevention of VEGF-induced vascular leakage and edema in connection with ischemic disorders....

Calcification of human vascular smooth muscle cells: associations with osteoprotegerin expression and acceleration by high-dose insulin

DEFF Research Database (Denmark)

Olesen, Ping; Knudsen, Kirsten Quyen Nguyen; Wogensen, Lise

2007-01-01

Arterial medial calcifications occur often in diabetic individuals as part of the diabetic macroangiopathy. The pathogenesis is unknown, but the presence of calcifications predicts risk of cardiovascular events. We examined the effects of insulin on calcifying smooth muscle cells in vitro...... and measured the expression of the bone-related molecule osteoprotegerin (OPG). Human vascular smooth muscle cells (VSMCs) were grown from aorta from kidney donors. Induction of calcification was performed with beta-glycerophosphate. The influence of insulin (200 microU/ml or 1,000 microU/ml) on calcification...... calcification in human smooth muscle cells from a series of donors after variable time in culture. Decreased OPG amounts were observed from the cells during the accelerated calcification phase. High dose of insulin (1,000 microU/ml) accelerated the calcification, whereas lower concentrations (200 microU/ml) did...

Magnesium Counteracts Vascular Calcification: Passive Interference or Active Modulation?

Science.gov (United States)

Ter Braake, Anique D; Shanahan, Catherine M; de Baaij, Jeroen H F

2017-08-01

Over the last decade, an increasing number of studies report a close relationship between serum magnesium concentration and cardiovascular disease risk in the general population. In end-stage renal disease, an association was found between serum magnesium and survival. Hypomagnesemia was identified as a strong predictor for cardiovascular disease in these patients. A substantial body of in vitro and in vivo studies has identified a protective role for magnesium in vascular calcification. However, the precise mechanisms and its contribution to cardiovascular protection remain unclear. There are currently 2 leading hypotheses: first, magnesium may bind phosphate and delay calcium phosphate crystal growth in the circulation, thereby passively interfering with calcium phosphate deposition in the vessel wall. Second, magnesium may regulate vascular smooth muscle cell transdifferentiation toward an osteogenic phenotype by active cellular modulation of factors associated with calcification. Here, the data supporting these major hypotheses are reviewed. The literature supports both a passive inorganic phosphate-buffering role reducing hydroxyapatite formation and an active cell-mediated role, directly targeting vascular smooth muscle transdifferentiation. However, current evidence relies on basic experimental designs that are often insufficient to delineate the underlying mechanisms. The field requires more advanced experimental design, including determination of intracellular magnesium concentrations and the identification of the molecular players that regulate magnesium concentrations in vascular smooth muscle cells. © 2017 American Heart Association, Inc.

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

Science.gov (United States)

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

2017-06-01

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

Vascular smooth muscle cell phenotypic changes in patients with Marfan syndrome.

Science.gov (United States)

Crosas-Molist, Eva; Meirelles, Thayna; López-Luque, Judit; Serra-Peinado, Carla; Selva, Javier; Caja, Laia; Gorbenko Del Blanco, Darya; Uriarte, Juan José; Bertran, Esther; Mendizábal, Yolanda; Hernández, Vanessa; García-Calero, Carolina; Busnadiego, Oscar; Condom, Enric; Toral, David; Castellà, Manel; Forteza, Alberto; Navajas, Daniel; Sarri, Elisabet; Rodríguez-Pascual, Fernando; Dietz, Harry C; Fabregat, Isabel; Egea, Gustavo

2015-04-01

Marfan's syndrome is characterized by the formation of ascending aortic aneurysms resulting from altered assembly of extracellular matrix microfibrils and chronic tissue growth factor (TGF)-β signaling. TGF-β is a potent regulator of the vascular smooth muscle cell (VSMC) phenotype. We hypothesized that as a result of the chronic TGF-β signaling, VSMC would alter their basal differentiation phenotype, which could facilitate the formation of aneurysms. This study explores whether Marfan's syndrome entails phenotypic alterations of VSMC and possible mechanisms at the subcellular level. Immunohistochemical and Western blotting analyses of dilated aortas from Marfan patients showed overexpression of contractile protein markers (α-smooth muscle actin, smoothelin, smooth muscle protein 22 alpha, and calponin-1) and collagen I in comparison with healthy aortas. VSMC explanted from Marfan aortic aneurysms showed increased in vitro expression of these phenotypic markers and also of myocardin, a transcription factor essential for VSMC-specific differentiation. These alterations were generally reduced after pharmacological inhibition of the TGF-β pathway. Marfan VSMC in culture showed more robust actin stress fibers and enhanced RhoA-GTP levels, which was accompanied by increased focal adhesion components and higher nuclear localization of myosin-related transcription factor A. Marfan VSMC and extracellular matrix measured by atomic force microscopy were both stiffer than their respective controls. In Marfan VSMC, both in tissue and in culture, there are variable TGF-β-dependent phenotypic changes affecting contractile proteins and collagen I, leading to greater cellular and extracellular matrix stiffness. Altogether, these alterations may contribute to the known aortic rigidity that precedes or accompanies Marfan's syndrome aneurysm formation. © 2015 American Heart Association, Inc.

Vitamin K2 inhibits rat vascular smooth muscle cell calcification by restoring the Gas6/Axl/Akt anti-apoptotic pathway.

Science.gov (United States)

Qiu, Cuiting; Zheng, Haijun; Tao, Huiren; Yu, Wenjun; Jiang, Xiaoyu; Li, Aiqin; Jin, Hui; Lv, Anlin; Li, Huan

2017-09-01

Vascular calcification is associated with cardiovascular disease as a complication of hypertension, hyperlipidemia, diabetes mellitus, and chronic kidney disease. Vitamin K2 (VK2) delays vascular calcification by an unclear mechanism. Moreover, apoptosis modulates vascular smooth muscle cell (VSMC) calcification. This paper aimed to study VK2-modified VSMC calcification and survival cell signaling mediated by growth arrest-specific gene 6 (Gas6) and its tyrosine kinase receptor Axl. Primary-cultured VSMCs were dose-dependently treated with VK2 in the presence of calcification medium for 8 days, or pre-treated for 1 h with/without the Axl inhibitor R428 (2 μmol/L) or the caspase inhibitor Z-VAD-fmk (20 μmol/L) followed by treatment with VK2 (10 μmol/L) or rmGas6 (200 nmol/L) in calcification medium for 8 days. Calcium deposition was determined by the o-cresolphthalein complexone assay and Alizarin Red S staining. Apoptosis was determined by TUNEL and flow cytometry using Annexin V-FITC and propidium iodide staining. Western blotting detected the expressions of Axl, Gas6, p-Akt, Akt, and Bcl2. VK2 significantly inhibited CaCl 2 - and β-sodium glycerophosphate (β-GP)-induced VSMC calcification and apoptosis, which was dependent on restored Gas6 expression and activated downstream signaling by Axl, p-Akt, and Bcl2. Z-VAD-fmk significantly inhibited CaCl 2 - and β-GP-induced VSMC calcification and apoptosis. Augmented recombinant mouse Gas6 protein (rmGas6) expression significantly reduced VSMC calcification and apoptosis. Furthermore, the Gas6/Axl interaction was inhibited by R428, which abolished the preventive effect of VK2 on CaCl 2 - and β-GP-induced apoptosis and calcification. These results suggest that Gas6 is critical in VK2-mediated functions that attenuate CaCl 2 - and β-GP-induced VSMC calcification by blocking apoptosis.

Effects of x-irradiation on growth of vascular smooth muscle cells

International Nuclear Information System (INIS)

Dzoga, K.F.; Dimitrievich, G.S.; Sutton, H.G.; Griem, M.L.

1984-01-01

Effects of x-irradiation doses ranging from 0-2000 rads on vascular smooth muscle cells were measured. Explant cultures were from the medial layers of aortas from New Zealand rabbits. X-irradiation was delivered to narrow mediastinal port using a 250 kV Maxitron at a rate of 80 rads/min. and a S-C distance of 60 cm. Explantation was done either immediately following radiation or five days later. Two parameters were used to determine post-irradiation growth potential of these cells: number of outgrowing cells per seeded explant and size and number of cells/culture. Results were expressed as fraction of control. Irradiation immediately before explantation reduced number of cells/ explant 10% for 250 rads and over 50% for 500 rads. Doses of 1000 rads and over resulted in reductions of over 70% in number of growing explants and culture size. When five days were allowed to elapse between x-irradiation and explantation the same parameters were not significantly affected for doses of 500 rads or less. Doses of 1000 rads resulted in a reduction in number of cells of 40% and 2000 rads of over 80%. These results suggest the presence of a population of vascular repair cells five days following irradiation treatment. The nature of these cells is discussed

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

International Nuclear Information System (INIS)

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

2013-01-01

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

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

Energy Technology Data Exchange (ETDEWEB)

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

2013-11-22

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

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

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Dan Huang

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

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

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 transformat......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......) 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...

Cyclic strain-induced endothelial MMP-2: role in vascular smooth muscle cell migration

International Nuclear Information System (INIS)

Sweeney, Nicholas von Offenberg; Cummins, Philip M.; Birney, Yvonne A.; Redmond, Eileen M.; Cahill, Paul A.

2004-01-01

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

Platelet-derived growth factor regulates K-Cl cotransport in vascular smooth muscle cells.

Science.gov (United States)

Zhang, Jing; Lauf, Peter K; Adragna, Norma C

2003-03-01

Platelet-derived growth factor (PDGF), a potent serum mitogen for vascular smooth muscle cells (VSMCs), plays an important role in membrane transport regulation and in atherosclerosis. K-Cl cotransport (K-Cl COT/KCC), the coupled-movement of K and Cl, is involved in ion homeostasis. VSMCs possess K-Cl COT activity and the KCC1 and KCC3 isoforms. Here, we report on the effect of PDGF on K-Cl COT activity and mRNA expression in primary cultures of rat VSMCs. K-Cl COT was determined as the Cl-dependent Rb influx and mRNA expression by semiquantitative RT-PCR. Twenty four-hour serum deprivation inhibited basal K-Cl COT activity. Addition of PDGF increased total protein content and K-Cl COT activity in a time-dependent manner. PDGF activated K-Cl COT in a dose-dependent manner, both acutely (10 min) and chronically (12 h). AG-1296, a selective inhibitor of the PDGF receptor tyrosine kinase, abolished these effects. Actinomycin D and cycloheximide had no effect on the acute PDGF activation of K-Cl COT, suggesting posttranslational regulation by the drug. Furthermore, PDGF increased KCC1 and decreased KCC3 mRNA expression in a time-dependent manner. These results indicate that chronic activation of K-Cl COT activity by PDGF may involve regulation of the two KCC mRNA isoforms, with KCC1 playing a dominant role in the mechanism of PDGF-mediated activation.

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

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Qianran Yin

2017-12-01

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

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

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Sherin Samuel

2017-04-01

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

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

Science.gov (United States)

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

2017-01-01

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

Clathrin-dependent internalization of the angiotensin II AT₁A receptor links receptor internalization to COX-2 protein expression in rat aortic vascular smooth muscle cells.

Science.gov (United States)

Morinelli, Thomas A; Walker, Linda P; Velez, Juan Carlos Q; Ullian, Michael E

2015-02-05

The major effects of Angiotensin II (AngII) in vascular tissue are mediated by AngII AT1A receptor activation. Certain effects initiated by AT1A receptor activation require receptor internalization. In rat aortic vascular smooth muscle cells (RASMC), AngII stimulates cyclooxygenase 2 protein expression. We have previously shown this is mediated by β-arrestin-dependent receptor internalization and NF-κB activation. In this study, a specific inhibitor of clathrin-mediated endocytosis (CME), pitstop-2, was used to test the hypothesis that clathrin-dependent internalization of activated AT1A receptor mediates NF-κB activation and subsequent cyclooxygenase 2 expression. Radioligand binding assays, real time qt-PCR and immunoblotting were used to document the effects of pitstop-2 on AngII binding and signaling in RASMC. Laser scanning confocal microscopy (LSCM) was used to image pitstop-2׳s effects on AT1 receptor/GFP internalization in HEK-293 cells and p65 NF-κB nuclear localization in RASMC. Pitstop-2 significantly inhibited internalization of AT1A receptor (44.7% ± 3.1% Control vs. 13.2% ± 8.3% Pitstop-2; n=3) as determined by radioligand binding studies in RASMC. Studies utilizing AT1A receptor/GFP expressed in HEK 293 cells and LSCM confirmed these findings. Pitstop-2 significantly inhibited AngII-induced p65 NF-κB phosphorylation and nuclear localization, COX-2 message and protein expression in RASMC without altering activation of p42/44 ERK or TNFα signaling. Pitstop-2, a specific inhibitor of clathrin-mediated endocytosis, confirms that internalization of activated AT1A receptor mediates AngII activation of cyclooxygenase 2 expression in RASMC. These data provide support for additional intracellular signaling pathways activated through β-arrestin mediated internalization of G protein-coupled receptors, such as AT1A receptors. Copyright © 2014 Elsevier B.V. All rights reserved.

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

Science.gov (United States)

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

2017-11-01

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

PDZK1 prevents neointima formation via suppression of breakpoint cluster region kinase in vascular smooth muscle.

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Wan Ru Lee

Full Text Available Scavenger receptor class B, type I (SR-BI and its adaptor protein PDZK1 mediate responses to HDL cholesterol in endothelium. Whether the receptor-adaptor protein tandem serves functions in other vascular cell types is unknown. The current work determined the roles of SR-BI and PDZK1 in vascular smooth muscle (VSM. To evaluate possible VSM functions of SR-BI and PDZK1 in vivo, neointima formation was assessed 21 days post-ligation in the carotid arteries of wild-type, SR-BI-/- or PDZK1-/- mice. Whereas neointima development was negligible in wild-type and SR-BI-/-, there was marked neointima formation in PDZK1-/- mice. PDZK1 expression was demonstrated in primary mouse VSM cells, and compared to wild-type cells, PDZK1-/- VSM displayed exaggerated proliferation and migration in response to platelet derived growth factor (PDGF. Tandem affinity purification-mass spectrometry revealed that PDZK1 interacts with breakpoint cluster region kinase (Bcr, which contains a C-terminal PDZ binding sequence and is known to enhance responses to PDGF in VSM. PDZK1 interaction with Bcr in VSM was demonstrated by pull-down and by coimmunoprecipitation, and the augmented proliferative response to PDGF in PDZK1-/- VSM was abrogated by Bcr depletion. Furthermore, compared with wild-type Bcr overexpression, the introduction of a Bcr mutant incapable of PDZK1 binding into VSM cells yielded an exaggerated proliferative response to PDGF. Thus, PDZK1 has novel SR-BI-independent function in VSM that affords protection from neointima formation, and this involves PDZK1 suppression of VSM cell proliferation via an inhibitory interaction with Bcr.

Vascular smooth muscle responsiveness to nitric oxide is reduced in healthy adults with increased adiposity

OpenAIRE

Christou, Demetra D.; Pierce, Gary L.; Walker, Ashley E.; Hwang, Moon-Hyon; Yoo, Jeung-Ki; Luttrell, Meredith; Meade, Thomas H.; English, Mark; Seals, Douglas R.

2012-01-01

Vascular smooth muscle responsiveness to nitric oxide, as assessed by nitroglycerin-induced dilation (NID), is impaired in clinical cardiovascular disease, but its relation to adiposity is unknown. We determined the relation of NID to total and abdominal adiposity in healthy adults varying widely in adiposity. In 224 men and women [age, 18–79 years; body mass index (BMI), 16.4–42.2 kg/m2], we measured NID (brachial artery dilation to 0.4 mg sublingual nitroglycerin), total body adiposity [BMI...

Gene expression profiling of resting and activated vascular smooth muscle cells by serial analysis of gene expression and clustering analysis

NARCIS (Netherlands)

Beauchamp, Nicholas J.; van Achterberg, Tanja A. E.; Engelse, Marten A.; Pannekoek, Hans; de Vries, Carlie J. M.

2003-01-01

Migration and proliferation of vascular smooth muscle cells (SMCs) are key events in atherosclerosis. However, little is known about alterations in gene expression upon transition of the quiescent, contractile SMC to the proliferative SMC. We performed serial analysis of gene expression (SAGE) of

MicroRNA-31 controls phenotypic modulation of human vascular smooth muscle cells by regulating its target gene cellular repressor of E1A-stimulated genes

International Nuclear Information System (INIS)

Wang, Jie; Yan, Cheng-Hui; Li, Yang; Xu, Kai; Tian, Xiao-Xiang; Peng, Cheng-Fei; Tao, Jie; Sun, Ming-Yu; Han, Ya-Ling

2013-01-01

Phenotypic modulation of vascular smooth muscle cells (VSMCs) plays a critical role in the pathogenesis of a variety of proliferative vascular diseases. The cellular repressor of E1A-stimulated genes (CREG) has been shown to play an important role in phenotypic modulation of VSMCs. However, the mechanism regulating CREG upstream signaling remains unclear. MicroRNAs (miRNAs) have recently been found to play a critical role in cell differentiation via target-gene regulation. This study aimed to identify a miRNA that binds directly to CREG, and may thus be involved in CREG-mediated VSMC phenotypic modulation. Computational analysis indicated that miR-31 bound to the CREG mRNA 3′ untranslated region (3′-UTR). miR-31 was upregulated in quiescent differentiated VSMCs and downregulated in proliferative cells stimulated by platelet-derived growth factor and serum starvation, demonstrating a negative relationship with the VSMC differentiation marker genes, smooth muscle α-actin, calponin and CREG. Using gain-of-function and loss-of-function approaches, CREG and VSMC differentiation marker gene expression levels were shown to be suppressed by a miR-31 mimic, but increased by a miR-31 inhibitor at both protein and mRNA levels. Notably, miR-31 overexpression or inhibition affected luciferase expression driven by the CREG 3′-UTR containing the miR-31 binding site. Furthermore, miR-31-mediated VSMC phenotypic modulation was inhibited in CREG-knockdown human VSMCs. We also determined miR-31 levels in the serum of patients with coronary artery disease (CAD), with or without in stent restenosis and in healthy controls. miR-31 levels were higher in the serum of CAD patients with restenosis compared to CAD patients without restenosis and in healthy controls. In summary, these data demonstrate that miR-31 not only directly binds to its target gene CREG and modulates the VSMC phenotype through this interaction, but also can be an important biomarker in diseases involving VSMC

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

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Qishan Chen

2013-01-01

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

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

NARCIS (Netherlands)

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

2009-01-01

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

The PPARα/p16INK4a Pathway inhibits Vascular Smooth Muscle Cell Proliferation by repressing Cell Cycle-dependent Telomerase Activation

Science.gov (United States)

Gizard, Florence; Nomiyama, Takashi; Zhao, Yue; Findeisen, Hannes M.; Heywood, Elizabeth B.; Jones, Karrie L.; Staels, Bart; Bruemmer, Dennis

2009-01-01

Peroxisome Proliferator-Activated Receptor (PPAR) α, the molecular target for fibrates used to treat dyslipidemia, exerts pleiotropic effects on vascular cells. In vascular smooth muscle cells (VSMCs), we have previously demonstrated that PPARα activation suppresses G1→S cell cycle progression by targeting the cyclin-dependent kinase inhibitor p16INK4a (p16). In the present study, we demonstrate that this inhibition of VSMC proliferation by PPARα is mediated through a p16-dependent suppression of telomerase activity, which has been implicated in key cellular functions including proliferation. PPARα activation inhibited mitogen-induced telomerase activity by repressing the catalytic subunit telomerase reverse transcriptase (TERT) through negative cross-talk with an E2F-1-dependent trans-activation of the TERT promoter. This trans-repression involved the recruitment of the retinoblastoma (RB) family proteins p107 and p130 to the TERT promoter resulting in impaired E2F-1 binding, an effect which was dependent on p16. The inhibition of cell proliferation by PPARα activation was lost in VSMC following TERT overexpression or knock-down, pointing to a key role of telomerase as a target for the antiproliferative effects of PPARα. Finally, we demonstrate that PPARα agonists suppress telomerase activation during the proliferative response following vascular injury indicating that these findings are applicable in vivo. In concert, these results demonstrate that the anti-proliferative effects of PPARα in VSMCs depend on the suppression of telomerase activity by targeting the p16/RB/E2F transcriptional cascade. PMID:18818403

Selective Inhibitory Effect of Epigallocatechin-3-gallate on Migration of Vascular Smooth Muscle Cells

Directory of Open Access Journals (Sweden)

Jong-Chul Park

2010-11-01

Full Text Available In order to prevent restenosis after angioplasty or stenting, one of the most popular targets is suppression of the abnormal growth and excess migration of vascular smooth muscle cells (VSMCs with drugs. However, the drugs also adversely affect vascular endothelial cells (VECs, leading to the induction of late thrombosis. We have investigated the effect of epigallocatechin-3-gallate (EGCG on the proliferation and migration of VECs and VSMCs. Both cells showed dose-dependent decrease of viability in response to EGCG while they have different IC50 values of EGCG (VECs, 150 mM and VSMCs, 1050 mM. Incubating both cells with EGCG resulted in significant reduction in cell proliferation irrespective of cell type. The proliferation of VECs were greater affected than that of VSMCs at the same concentrations of EGCG. EGCG exerted differential migration-inhibitory activity in VECs vs. VSMCs. The migration of VECs was not attenuated by 200 mM EGCG, but that of VSMCs was significantly inhibited at the same concentration of EGCG. It is suggested that that EGCG can be effectively used as an efficient drug for vascular diseases or stents due to its selective activity, completely suppressing the proliferation and migration of VSMCs, but not adversely affecting VECs migration in blood vessels.

Vascular smooth muscle modulates endothelial control of vasoreactivity via reactive oxygen species production through myoendothelial communications.

Directory of Open Access Journals (Sweden)

Marie Billaud

Full Text Available BACKGROUND: Endothelial control of vascular smooth muscle plays a major role in the resulting vasoreactivity implicated in physiological or pathological circulatory processes. However, a comprehensive understanding of endothelial (EC/smooth muscle cells (SMC crosstalk is far from complete. Here, we have examined the role of gap junctions and reactive oxygen species (ROS in this crosstalk and we demonstrate an active contribution of SMC to endothelial control of vasomotor tone. METHODOLOGY/PRINCIPAL FINDINGS: In small intrapulmonary arteries, quantitative RT-PCR, Western Blot analyses and immunofluorescent labeling evidenced connexin (Cx 37, 40 and 43 in EC and/or SMC. Functional experiments showed that the Cx-mimetic peptide targeted against Cx 37 and Cx 43 ((37,43Gap27 (1 reduced contractile and calcium responses to serotonin (5-HT simultaneously recorded in pulmonary arteries and (2 abolished the diffusion in SMC of carboxyfluorescein-AM loaded in EC. Similarly, contractile and calcium responses to 5-HT were decreased by superoxide dismutase and catalase which, catabolise superoxide anion and H(2O(2, respectively. Both Cx- and ROS-mediated effects on the responses to 5-HT were reversed by L-NAME, a NO synthase inhibitor or endothelium removal. Electronic paramagnetic resonance directly demonstrated that 5-HT-induced superoxide anion production originated from the SMC. Finally, whereas 5-HT increased NO production, it also decreased cyclic GMP content in isolated intact arteries. CONCLUSIONS/SIGNIFICANCE: These data demonstrate that agonist-induced ROS production in SMC targeting EC via myoendothelial gap junctions reduces endothelial NO-dependent control of pulmonary vasoreactivity. Such SMC modulation of endothelial control may represent a signaling pathway controlling vasoreactivity under not only physiological but also pathological conditions that often implicate excessive ROS production.

Differential regulation of protease activated receptor-1 and tissue plasminogen activator expression by shear stress in vascular smooth muscle cells

Science.gov (United States)

Papadaki, M.; Ruef, J.; Nguyen, K. T.; Li, F.; Patterson, C.; Eskin, S. G.; McIntire, L. V.; Runge, M. S.

1998-01-01

Recent studies have demonstrated that vascular smooth muscle cells are responsive to changes in their local hemodynamic environment. The effects of shear stress on the expression of human protease activated receptor-1 (PAR-1) and tissue plasminogen activator (tPA) mRNA and protein were investigated in human aortic smooth muscle cells (HASMCs). Under conditions of low shear stress (5 dyn/cm2), PAR-1 mRNA expression was increased transiently at 2 hours compared with stationary control values, whereas at high shear stress (25 dyn/cm2), mRNA expression was decreased (to 29% of stationary control; Pmuscle cells, indicating that the effects of shear stress on human PAR-1 were not species-specific. Flow cytometry and ELISA techniques using rat smooth muscle cells and HASMCs, respectively, provided evidence that shear stress exerted similar effects on cell surface-associated PAR-1 and tPA protein released into the conditioned media. The decrease in PAR-1 mRNA and protein had functional consequences for HASMCs, such as inhibition of [Ca2+] mobilization in response to thrombin stimulation. These data indicate that human PAR-1 and tPA gene expression are regulated differentially by shear stress, in a pattern consistent with their putative roles in several arterial vascular pathologies.

Statins meditate anti-atherosclerotic action in smooth muscle cells by peroxisome proliferator-activated receptor-γ activation

Energy Technology Data Exchange (ETDEWEB)

Fukuda, Kazuki [Department of Metabolic Medicine, Faculty of Life Sciences, Kumamoto University, Kumamoto (Japan); Matsumura, Takeshi, E-mail: takeshim@gpo.kumamoto-u.ac.jp [Department of Metabolic Medicine, Faculty of Life Sciences, Kumamoto University, Kumamoto (Japan); Senokuchi, Takafumi; Ishii, Norio; Kinoshita, Hiroyuki; Yamada, Sarie; Murakami, Saiko [Department of Metabolic Medicine, Faculty of Life Sciences, Kumamoto University, Kumamoto (Japan); Nakao, Saya [Department of Environmental & Symbiotic Sciences, Prefectural University of Kumamoto, Kumamoto (Japan); Motoshima, Hiroyuki; Kondo, Tatsuya; Kukidome, Daisuke; Kawasaki, Shuji [Department of Metabolic Medicine, Faculty of Life Sciences, Kumamoto University, Kumamoto (Japan); Kawada, Teruo [Laboratory of Nutrition Chemistry, Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Kyoto (Japan); Nishikawa, Takeshi; Araki, Eiichi [Department of Metabolic Medicine, Faculty of Life Sciences, Kumamoto University, Kumamoto (Japan)

2015-01-30

Highlights: • Statins induce PPARγ activation in vascular smooth muscle cells. • Statin-induced PPARγ activation is mediated by COX-2 expression. • Statins suppress cell migration and proliferation in vascular smooth muscle cells. • Statins inhibit LPS-induced inflammatory responses by PPARγ activation. • Fluvastatin suppress the progression of atherosclerosis and induces PPARγ activation in the aorta of apoE-deficient mice. - Abstract: The peroxisome proliferator-activated receptor-γ (PPARγ) is an important regulator of lipid and glucose metabolism, and its activation is reported to suppress the progression of atherosclerosis. We have reported that 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (statins) activate PPARγ in macrophages. However, it is not yet known whether statins activate PPARγ in other vascular cells. In the present study, we investigated whether statins activate PPARγ in smooth muscle cells (SMCs) and endothelial cells (ECs) and thus mediate anti-atherosclerotic effects. Human aortic SMCs (HASMCs) and human umbilical vein ECs (HUVECs) were used in this study. Fluvastatin and pitavastatin activated PPARγ in HASMCs, but not in HUVECs. Statins induced cyclooxygenase-2 (COX-2) expression in HASMCs, but not in HUVECs. Moreover, treatment with COX-2-siRNA abrogated statin-mediated PPARγ activation in HASMCs. Statins suppressed migration and proliferation of HASMCs, and inhibited lipopolysaccharide-induced expression of monocyte chemoattractant protein-1 (MCP-1) and tumor necrosis factor-α (TNF-α) in HASMCs. These effects of statins were abrogated by treatment with PPARγ-siRNA. Treatment with statins suppressed atherosclerotic lesion formation in Apoe{sup −/−} mice. In addition, transcriptional activity of PPARγ and CD36 expression were increased, and the expression of MCP-1 and TNF-α was decreased, in the aorta of statin-treated Apoe{sup −/−} mice. In conclusion, statins mediate anti-atherogenic effects

Mediators on human airway smooth muscle.

Science.gov (United States)

Armour, C; Johnson, P; Anticevich, S; Ammit, A; McKay, K; Hughes, M; Black, J

1997-01-01

1. Bronchial hyperresponsiveness in asthma may be due to several abnormalities, but must include alterations in the airway smooth muscle responsiveness and/or volume. 2. Increased responsiveness of airway smooth muscle in vitro can be induced by certain inflammatory cell products and by induction of sensitization (atopy). 3. Increased airway smooth muscle growth can also be induced by inflammatory cell products and atopic serum. 4. Mast cell numbers are increased in the airways of asthmatics and, in our studies, in airway smooth muscle that is sensitized and hyperresponsive. 5. We propose that there is a relationship between mast cells and airway smooth muscle cells which, once an allergic process has been initiated, results in the development of critical features in the lungs in asthma.

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

/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......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...... 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...

The influence of perivascular adipose tissue on vascular homeostasis.

Science.gov (United States)

Szasz, Theodora; Bomfim, Gisele Facholi; Webb, R Clinton

2013-01-01

The perivascular adipose tissue (PVAT) is now recognized as an active contributor to vascular function. Adipocytes and stromal cells contained within PVAT are a source of an ever-growing list of molecules with varied paracrine effects on the underlying smooth muscle and endothelial cells, including adipokines, cytokines, reactive oxygen species, and gaseous compounds. Their secretion is regulated by systemic or local cues and modulates complex processes, including vascular contraction and relaxation, smooth muscle cell proliferation and migration, and vascular inflammation. Recent evidence demonstrates that metabolic and cardiovascular diseases alter the morphological and secretory characteristics of PVAT, with notable consequences. In obesity and diabetes, the expanded PVAT contributes to vascular insulin resistance. PVAT-derived cytokines may influence key steps of atherogenesis. The physiological anticontractile effect of PVAT is severely diminished in hypertension. Above all, a common denominator of the PVAT dysfunction in all these conditions is the immune cell infiltration, which triggers the subsequent inflammation, oxidative stress, and hypoxic processes to promote vascular dysfunction. In this review, we discuss the currently known mechanisms by which the PVAT influences blood vessel function. The important discoveries in the study of PVAT that have been made in recent years need to be further advanced, to identify the mechanisms of the anticontractile effects of PVAT, to explore the vascular-bed and species differences in PVAT function, to understand the regulation of PVAT secretion of mediators, and finally, to uncover ways to ameliorate cardiovascular disease by targeting therapeutic approaches to PVAT.

Polysaccharide from Fuzi protects against Ox-LDL-induced calcification of human vascular smooth muscle cells by increasing autophagic activity

Science.gov (United States)

Liao, Lizhen; Zhuang, Xiaodong; Li, Weidong; Su, Qibiao; Zhao, Jie; Liu, Ying

2018-01-01

Polysaccharide from Fuzi (FPS) is a water-soluble polysaccharide isolated from the traditional Chinese herbal medicine Fuzi. It has been demonstrated to protect hepatocytes against ischemia-reperfusion injury through its potent antioxidant effects, and to attenuate starvation-induced cytotoxicity in H9c2 cells by increasing autophagic activity. In the present study, Alizarin Red S staining was used to detect mineral deposition and reverse transcription-quantitative polymerase chain reaction was used to detect the core binding factor α1 and smooth muscle 22α mRNA expression. To analyze autophagic activity, western blotting was used to detect microtubule-associated protein 1A/1B light chain 3 and nucleoporin P62 expression. In addition, green fluorescent protein-LC3 dots-per-cell was observed by fluorescence microscopy. It was demonstrated that oxidized low-density lipoprotein (Ox-LDL) could increase the calcification of human vascular smooth muscle cells (VSMCs) in a concentration-dependent manner, and that FPS treatment had a significant protective effect against Ox-LDL-induced calcification of human VSMCs. Furthermore, FPS treatment alleviated the Ox-LDL-induced downregulation of autophagic activity, and the protective effect of FPS on Ox-LDL-induced calcification was attenuated by the autophagy inhibitor 3-methyladenine. In conclusion, the present study demonstrated for the first time to the best of the authors' knowledge that FPS can protect against Ox-LDL-induced vascular calcification in human VSMCs, and that this likely occurs via the activation of autophagy. This supports the hypothesis that autophagy may be an endogenous protective mechanism counteracting vascular calcification, and that FPS may be used as a potential therapeutic for vascular calcification. PMID:29393437

Msx1 and Msx2 are expressed in sub-populations of vascular smooth muscle cells.

Science.gov (United States)

Goupille, Olivier; Saint Cloment, Cécile; Lopes, Miguel; Montarras, Didier; Robert, Benoît

2008-08-01

Using an nlacZ reporter gene inserted at the Msx1 and Msx2 loci, we could analyze the expression of these homeogenes in the adult mouse. We observed that Msx genes are prominently expressed in a subset of blood vessels. The Msx2nlacZ allele is mainly expressed in a restricted population of mural cells in peripheral arteries and veins. Msx1nlacZ is expressed to a lesser extent by vascular smooth muscle cells of peripheral arteries, but is highly expressed in arterioles and capillaries, making Msx1 a novel marker for a subpopulation of pericytes. Expression is set up early in developing vessels and maintained throughout life. In addition, expression of both genes is observed in a few endothelial cells of the aorta at fetal stages, and only Msx2 continues to be expressed in this layer at the adult stage. These results suggest major functions for Msx genes in vascular mural cell formation and remodeling. Copyright (c) 2008 Wiley-Liss, Inc.

Protective effects of estrogen against vascular calcification via estrogen receptor α-dependent growth arrest-specific gene 6 transactivation

International Nuclear Information System (INIS)

Nanao-Hamai, Michiko; Son, Bo-Kyung; Hashizume, Tsuyoshi; Ogawa, Sumito; Akishita, Masahiro

2016-01-01

Vascular calcification is one of the major complications of cardiovascular disease and is an independent risk factor for myocardial infarction and cardiac death. Postmenopausal women have a higher prevalence of vascular calcification compared with premenopausal women, suggesting protective effects of estrogen (E2). However, the underlying mechanisms of its beneficial effects remain unclear. In the present study, we examined the inhibitory effects of E2 on vascular smooth muscle cell (VSMC) calcification, and found that growth arrest-specific gene 6 (Gas6), a crucial molecule in vascular calcification, is transactivated by estrogen receptor α (ERα) in response to E2. In human aortic smooth muscle cells, physiological levels of E2 inhibited inorganic phosphate (Pi)-induced calcification in a concentration-dependent manner. This inhibitory effect was significantly abolished by MPP, an ERα-selective antagonist, and ERα siRNA, but not by PHTPP, an ERβ-selective antagonist, and ERβ siRNA, implicating an ERα-dependent action. Apoptosis, an essential process for Pi-induced VSMC calcification, was inhibited by E2 in a concentration-dependent manner and further, MPP abolished this inhibition. Mechanistically, E2 restored the inhibited expression of Gas6 and phospho-Akt in Pi-induced apoptosis through ERα. Furthermore, E2 significantly activated Gas6 transcription, and MPP abrogated this E2-dependent Gas6 transactivation. E2-BSA failed to activate Gas6 transcription and to inhibit Ca deposition in VSMC, suggesting beneficial actions of genomic signaling by E2/nuclear ERα. Taken together, these results indicate that E2 exerts inhibitory effects on VSMC apoptosis and calcification through ERα-mediated Gas6 transactivation. These findings indicate a potential therapeutic strategy for the prevention of vascular calcification, especially in postmenopausal women. - Highlights: • E2 inhibits Pi-induced calcification in vascular smooth muscles cells. • E2 inhibits Pi

Vascular smooth muscle cell apoptosis is an early trigger for hypothyroid atherosclerosis.

Science.gov (United States)

Wang, Pei; Xu, Tian-Ying; Guan, Yun-Feng; Zhao, Yan; Li, Zhi-Yong; Lan, Xiao-Hong; Wang, Xia; Yang, Peng-Yuan; Kang, Zhi-Min; Vanhoutte, Paul M; Miao, Chao-Yu

2014-06-01

Endothelial dysfunction is an initial and vascular smooth muscle cell (VSMC) apoptosis, a later step of atherosclerosis. Hypothyroidism accelerates atherosclerosis. However, the early events responsible for this pro-atherosclerotic effect are unclear. Rats were resistant to induction of atherosclerosis by high cholesterol diet alone, but became susceptible in hypothyroid state achieved by administration of propylthiouracil (PTU) for 6 weeks. VSMC dysfunction and apoptosis were obvious within 1 week after PTU treatment, without signs of endothelial dysfunction. This early VSMC damage was caused by hypothyroidism but not the high cholesterol diet. In ApoE knockout mice, PTU-induced hypothyroidism triggered early VSMC apoptosis, increased oxidative stress, and accelerated atherosclerosis development. Thyroid hormone supplementation (T4, 10, or 50 μg/kg) prevented atherogenic phenotypes in hypothyroid rats and mice. In rats, thyroidectomy caused severe hypothyroidism 5 days after operation, which also led to rapid VSMC dysfunction and apoptosis. In vitro studies did not show a direct toxic effect of PTU on VSMCs. In contrast, thyroid hormone (T3, 0.75 μg/L plus T4, 50 nmol/L) exerted a direct protection against VSMC apoptosis, which was reduced by knockdown of TRα1, rather than TRβ1 and TRβ2 receptors. TRα1-mediated inhibition of apoptotic signalling of JNKs and caspase-3 contributed to the anti-apoptotic action of thyroid hormone. These findings provide an in vivo example for VSMC apoptosis as an early trigger of hypothyroidism-associated atherosclerosis, and reveal activation of TRα1 receptors to prevent VSMC apoptosis as a therapeutic strategy in this disease. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2014. For permissions please email: journals.permissions@oup.com.

Overexpression of Mitofusin 2 inhibited oxidized low-density lipoprotein induced vascular smooth muscle cell proliferation and reduced atherosclerotic lesion formation in rabbit

International Nuclear Information System (INIS)

Guo Yanhong; Chen Kuanghueih; Gao Wei; Li Qian; Chen Li; Wang Guisong; Tang Jian

2007-01-01

Our previous studies have implies that Mitofusin 2 (Mfn2), which was progressively reduced in arteries from ApoE -/- mice during the development of atherosclerosis, may take part in pathogenesis of atherosclerosis. In this study, we found that overexpression of Mfn2 inhibited oxidized low-density lipoprotein or serum induced vascular smooth muscle cell proliferation by down-regulation of Akt and ERK phosphorylation. Then we investigated the in vivo role of Mfn2 on the development of atherosclerosis in rabbits using adenovirus expressing Mitofusin 2 gene (AdMfn2). By morphometric analysis we found overexpression of Mfn2 inhibited atherosclerotic lesion formation and intima/media ratio by 66.7% and 74.6%, respectively, compared with control group. These results suggest that local Mfn2 treatment suppresses the development of atherosclerosis in vivo in part by attenuating the smooth muscle cell proliferation induced by lipid deposition and vascular injury

Arginase strongly impairs neuronal nitric oxide-mediated airway smooth muscle relaxation in allergic asthma

NARCIS (Netherlands)

Maarsingh, H; Leusink, J; Bos, I Sophie T; Zaagsma, J; Meurs, H

2006-01-01

Background: Using guinea pig tracheal preparations, we have recently shown that endogenous arginase activity attenuates inhibitory nonadrenergic noncholinergic (iNANC) nerve-mediated airway smooth muscle relaxation by reducing nitric oxide (NO) production - due to competition with neuronal

Transcriptional up-regulation of antioxidant genes by PPARδ inhibits angiotensin II-induced premature senescence in vascular smooth muscle cells

International Nuclear Information System (INIS)

Kim, Hyo Jung; Ham, Sun Ah; Paek, Kyung Shin; Hwang, Jung Seok; Jung, Si Young; Kim, Min Young; Jin, Hanna; Kang, Eun Sil; Woo, Im Sun; Kim, Hye Jung; Lee, Jae Heun; Chang, Ki Churl; Han, Chang Woo; Seo, Han Geuk

2011-01-01

Research highlights: → Activation of PPARδ by GW501516 significantly inhibited Ang II-induced premature senescence in hVSMCs. → Agonist-activated PPARδ suppressed generation of Ang II-triggered ROS with a concomitant reduction in DNA damage. → GW501516 up-regulated expression of antioxidant genes, such as GPx1, Trx1, Mn-SOD and HO-1. → Knock-down of these antioxidant genes abolished the effects of GW501516 on ROS production and premature senescence. -- Abstract: This study evaluated peroxisome proliferator-activated receptor (PPAR) δ as a potential target for therapeutic intervention in Ang II-induced senescence in human vascular smooth muscle cells (hVSMCs). Activation of PPARδ by GW501516, a specific agonist of PPARδ, significantly inhibited the Ang II-induced premature senescence of hVSMCs. Agonist-activated PPARδ suppressed the generation of Ang II-triggered reactive oxygen species (ROS) with a concomitant reduction in DNA damage. Notably, GW501516 up-regulated the expression of antioxidant genes, such as glutathione peroxidase 1, thioredoxin 1, manganese superoxide dismutase and heme oxygenase 1. siRNA-mediated down-regulation of these antioxidant genes almost completely abolished the effects of GW501516 on ROS production and premature senescence in hVSMCs treated with Ang II. Taken together, the enhanced transcription of antioxidant genes is responsible for the PPARδ-mediated inhibition of premature senescence through sequestration of ROS in hVSMCs treated with Ang II.

Ageing induced vascular smooth muscle cell senescence in atherosclerosis.

Science.gov (United States)

Uryga, Anna K; Bennett, Martin R

2016-04-15

Atherosclerosis is a disease of ageing in that its incidence and prevalence increase with age. However, atherosclerosis is also associated with biological ageing, manifest by a number of typical hallmarks of ageing in the atherosclerotic plaque. Thus, accelerated biological ageing may be superimposed on the effects of chronological ageing in atherosclerosis. Tissue ageing is seen in all cells that comprise the plaque, but particularly in vascular smooth muscle cells (VSMCs). Hallmarks of ageing include evidence of cell senescence, DNA damage (including telomere attrition), mitochondrial dysfunction, a pro-inflammatory secretory phenotype, defects in proteostasis, epigenetic changes, deregulated nutrient sensing, and exhaustion of progenitor cells. In this model, initial damage to DNA (genomic, telomeric, mitochondrial and epigenetic changes) results in a number of cellular responses (cellular senescence, deregulated nutrient sensing and defects in proteostasis). Ultimately, ongoing damage and attempts at repair by continued proliferation overwhelm reparative capacity, causing loss of specialised cell functions, cell death and inflammation. This review summarises the evidence for accelerated biological ageing in atherosclerosis, the functional consequences of cell ageing on cells comprising the plaque, and the causal role that VSMC senescence plays in atherogenesis. © 2015 The Authors. The Journal of Physiology © 2015 The Physiological Society.

A 310-bp minimal promoter mediates smooth muscle cell-specific expression of telokin.

Science.gov (United States)

Smith, A F; Bigsby, R M; Word, R A; Herring, B P

1998-05-01

A cell-specific promoter located in an intron of the smooth muscle myosin light chain kinase gene directs transcription of telokin exclusively in smooth muscle cells. Transgenic mice were generated in which a 310-bp rabbit telokin promoter fragment, extending from -163 to +147, was used to drive expression of simian virus 40 large T antigen. Smooth muscle-specific expression of the T-antigen transgene paralleled that of the endogenous telokin gene in all smooth muscle tissues except uterus. The 310-bp promoter fragment resulted in very low levels of transgene expression in uterus; in contrast, a transgene driven by a 2.4-kb fragment (-2250 to +147) resulted in high levels of transgene expression in uterine smooth muscle. Telokin expression levels correlate with the estrogen status of human myometrial tissues, suggesting that deletion of an estrogen response element (ERE) may account for the low levels of transgene expression driven by the 310-bp rabbit telokin promoter in uterine smooth muscle. Experiments in A10 smooth muscle cells directly showed that reporter gene expression driven by the 2.4-kb, but not 310-bp, promoter fragment could be stimulated two- to threefold by estrogen. This stimulation was mediated through an ERE located between -1447 and -1474. Addition of the ERE to the 310-bp fragment restored estrogen responsiveness in A10 cells. These data demonstrate that in addition to a minimal 310-bp proximal promoter at least one distal cis-acting regulatory element is required for telokin expression in uterine smooth muscle. The distal element may include an ERE between -1447 and -1474.

IGF-I Stimulates Cooperative Interaction between the IGF-I Receptor and CSK Homologous Kinase that Regulates SHPS-1 Phosphorylation in Vascular Smooth Muscle Cells

Science.gov (United States)

Radhakrishnan, Yashwanth; Shen, Xinchun; Maile, Laura A.; Xi, Gang

2011-01-01

IGF-I plays an important role in smooth muscle cell proliferation and migration. In vascular smooth muscle cells cultured in 25 mm glucose, IGF-I stimulated a significant increase in Src homology 2 domain containing protein tyrosine phosphatase substrate-1 (SHPS-1) phosphorylation compared with 5 mm glucose and this increase was required for smooth muscle cell proliferation. A proteome-wide screen revealed that carboxyl-terminal SRC kinase homologous kinase (CTK) bound directly to phosphotyrosines in the SHPS-1 cytoplasmic domain. Because the kinase(s) that phosphorylates these tyrosines in response to IGF-I is unknown, we determined the roles of IGF-I receptor (IGF-IR) and CTK in mediating SHPS-1 phosphorylation. After IGF-I stimulation, CTK was recruited to IGF-IR and subsequently to phospho-SHPS-1. Expression of an IGF-IR mutant that eliminated CTK binding reduced CTK transfer to SHPS-1, SHPS-1 phosphorylation, and cell proliferation. IGF-IR phosphorylated SHPS-1, which provided a binding site for CTK. CTK recruitment to SHPS-1 resulted in a further enhancement of SHPS-1 phosphorylation. CTK knockdown also impaired IGF-I-stimulated SHPS-1 phosphorylation and downstream signaling. Analysis of specific tyrosines showed that mutation of tyrosines 428/452 in SHPS-1 to phenylalanine reduced SHPS-1 phosphorylation but allowed CTK binding. In contrast, the mutation of tyrosines 469/495 inhibited IGF-IR-mediated the phosphorylation of SHPS-1 and CTK binding, suggesting that IGF-IR phosphorylated Y469/495, allowing CTK binding, and that CTK subsequently phosphorylated Y428/452. Based on the above findings, we conclude that after IGF-I stimulation, CTK is recruited to IGF-IR and its recruitment facilitates CTK's subsequent association with phospho-SHPS-1. This results in the enhanced CTK transfer to SHPS-1, and the two kinases then fully phosphorylate SHPS-1, which is necessary for IGF-I stimulated cellular proliferation. PMID:21799000

Neuroblast survival depends on mature vascular network formation after mouse stroke: role of endothelial and smooth muscle progenitor cell co-administration.

Science.gov (United States)

Nih, Lina R; Deroide, Nicolas; Leré-Déan, Carole; Lerouet, Dominique; Soustrat, Mathieu; Levy, Bernard I; Silvestre, Jean-Sébastien; Merkulova-Rainon, Tatiana; Pocard, Marc; Margaill, Isabelle; Kubis, Nathalie

2012-04-01

Pro-angiogenic cell-based therapies constitute an interesting and attractive approach to enhancing post-stroke neurogenesis and decreasing neurological deficit. However, most new stroke-induced neurons die during the first few weeks after ischemia, thus impairing total recovery. Although the neovascularization process involves different cell types and various growth factors, most cell therapy protocols are based on the biological effects of single-cell-type populations or on the administration of heterogeneous populations of progenitors, namely human cord blood-derived CD34(+) cells, with scarce vascular progenitor cells. Tight cooperation between endothelial cells and smooth muscle cells/pericytes is critical for the development of functional neovessels. We hypothesized that neuroblast survival in stroke brain depends on mature vascular network formation. In this study, we injected a combination of endothelial progenitor cells (EPCs) and smooth muscle progenitor cells (SMPCs), isolated from human umbilical cord blood, into a murine model of permanent focal ischemia induced by middle cerebral artery occlusion. The co-administration of SMPCs and EPCs induced enhanced angiogenesis and vascular remodeling in the peri-infarct and infarct areas, where vessels exhibited a more mature phenotype. This activation of vessel growth resulted in the maintenance of neurogenesis and neuroblast migration to the peri-ischemic cortex. Our data suggest that a mature vascular network is essential for neuroblast survival after cerebral ischemia, and that co-administration of EPCs and SMPCs may constitute a novel therapeutic strategy for improving the treatment of stroke. © 2012 The Authors. European Journal of Neuroscience © 2012 Federation of European Neuroscience Societies and Blackwell Publishing Ltd.

Thrombospondin-1, -2 and -5 have differential effects on vascular smooth muscle cell physiology

Energy Technology Data Exchange (ETDEWEB)

Helkin, Alex; Maier, Kristopher G. [SUNY Upstate Medical University, Division of Vascular Surgery and Endovascular Services, Syracuse, NY (United States); Department of Veterans Affairs VA Healthcare Network Upstate New York at Syracuse, Syracuse, NY (United States); Gahtan, Vivian, E-mail: gahtanv@upstate.edu [SUNY Upstate Medical University, Division of Vascular Surgery and Endovascular Services, Syracuse, NY (United States); Department of Veterans Affairs VA Healthcare Network Upstate New York at Syracuse, Syracuse, NY (United States)

2015-09-04

Introduction: The thrombospondins (TSPs) are matricellular proteins that exert multifunctional effects by binding cytokines, cell-surface receptors and other proteins. TSPs play important roles in vascular pathobiology and are all expressed in arterial lesions. The differential effects of TSP-1, -2, and -5 represent a gap in knowledge in vascular smooth muscle cell (VSMC) physiology. Our objective is to determine if structural differences of the TSPs imparted different effects on VSMC functions critical to the formation of neointimal hyperplasia. We hypothesize that TSP-1 and -2 induce similar patterns of migration, proliferation and gene expression, while the effects of TSP-5 are different. Methods: Human aortic VSMC chemotaxis was tested for TSP-2 and TSP-5 (1–40 μg/mL), and compared to TSP-1 and serum-free media (SFM) using a modified Boyden chamber. Next, VSMCs were exposed to TSP-1, TSP-2 or TSP-5 (0.2–40 μg/mL). Proliferation was assessed by MTS assay. Finally, VSMCs were exposed to TSP-1, TSP-2, TSP-5 or SFM for 3, 6 or 24 h. Quantitative real-time PCR was performed on 96 genes using a microfluidic card. Statistical analysis was performed by ANOVA or t-test, with p < 0.05 being significant. Results: TSP-1, TSP-2 and TSP-5 at 20 μg/mL all induce chemotaxis 3.1 fold compared to serum-free media. TSP-1 and TSP-2 induced proliferation 53% and 54% respectively, whereas TSP-5 did not. In the gene analysis, overall, cardiovascular system development and function is the canonical pathway most influenced by TSP treatment, and includes multiple growth factors, cytokines and proteases implicated in cellular migration, proliferation, vasculogenesis, apoptosis and inflammation pathways. Conclusions and relevance: The results of this study indicate TSP-1, -2, and -5 play active roles in VSMC physiology and gene expression. Similarly to TSP-1, VSMC chemotaxis to TSP-2 and -5 is dose-dependent. TSP-1 and -2 induces VSMC proliferation, but TSP-5 does not, likely

Unexpected role of the copper transporter ATP7A in PDGF-induced vascular smooth

Energy Technology Data Exchange (ETDEWEB)

Ashino, T.; Varadarajan, S.; Urao, N.; Oshikawa, J.; Chen, G. -F.; Wang, H.; Huo, Y.; Finney, L.; Vogt, S.; McKinney, R. D.; Maryon, E. B.; Kaplan, J. H.; Ushio-Fukai, M.; Fukai, T. (Biosciences Division); ( XSD); ( PSC-USR); (Univ. of Illinois at Chicago); (Univ. of Minnesota)

2010-09-09

Copper, an essential nutrient, has been implicated in vascular remodeling and atherosclerosis with unknown mechanism. Bioavailability of intracellular copper is regulated not only by the copper importer CTR1 (copper transporter 1) but also by the copper exporter ATP7A (Menkes ATPase), whose function is achieved through copper-dependent translocation from trans-Golgi network (TGN). Platelet-derived growth factor (PDGF) promotes vascular smooth muscle cell (VSMC) migration, a key component of neointimal formation. To determine the role of copper transporter ATP7A in PDGF-induced VSMC migration. Depletion of ATP7A inhibited VSMC migration in response to PDGF or wound scratch in a CTR1/copper-dependent manner. PDGF stimulation promoted ATP7A translocation from the TGN to lipid rafts, which localized at the leading edge, where it colocalized with PDGF receptor and Rac1, in migrating VSMCs. Mechanistically, ATP7A small interfering RNA or CTR small interfering RNA prevented PDGF-induced Rac1 translocation to the leading edge, thereby inhibiting lamellipodia formation. In addition, ATP7A depletion prevented a PDGF-induced decrease in copper level and secretory copper enzyme precursor prolysyl oxidase (Pro-LOX) in lipid raft fraction, as well as PDGF-induced increase in LOX activity. In vivo, ATP7A expression was markedly increased and copper accumulation was observed by synchrotron-based x-ray fluorescence microscopy at neointimal VSMCs in wire injury model. These findings suggest that ATP7A plays an important role in copper-dependent PDGF-stimulated VSMC migration via recruiting Rac1 to lipid rafts at the leading edge, as well as regulating LOX activity. This may contribute to neointimal formation after vascular injury. Our findings provide insight into ATP7A as a novel therapeutic target for vascular remodeling and atherosclerosis.

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

Science.gov (United States)

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

2005-07-01

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

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

OpenAIRE

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

1996-01-01

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

Constituents of Mediterranean Spices Counteracting Vascular Smooth Muscle Cell Proliferation: Identification and Characterization of Rosmarinic Acid Methyl Ester as a Novel Inhibitor

Czech Academy of Sciences Publication Activity Database

Liu, R.; Heiss, E.H.; Waltenberger, B.; Blažević, T.; Schachner, B.; Jiang, B.; Kryštof, Vladimír; Liu, W.; Schwaiger, S.; Peña-Rodríguez, L. M.; Breuss, J.; Stuppner, H.; Dirsch, V.M.; Atanasov, A. G.

2018-01-01

Roč. 62, č. 7 (2018), č. článku 1700860. ISSN 1613-4125 Institutional support: RVO:61389030 Keywords : Mediterranean spices * neointima formation * rosmarinic acid * rosmarinic acid methyl ester * vascular smooth muscle cells Subject RIV: CE - Biochemistry OBOR OECD: Biochemical research methods Impact factor: 4.323, year: 2016

Intermittent hypoxia induces the proliferation of rat vascular smooth muscle cell with the increases in epidermal growth factor family and erbB2 receptor

International Nuclear Information System (INIS)

Kyotani, Yoji; Ota, Hiroyo; Itaya-Hironaka, Asako; Yamauchi, Akiyo; Sakuramoto-Tsuchida, Sumiyo; Zhao, Jing; Ozawa, Kentaro; Nagayama, Kosuke; Ito, Satoyasu; Takasawa, Shin; Kimura, Hiroshi; Uno, Masayuki; Yoshizumi, Masanori

2013-01-01

Obstructive sleep apnea is characterized by intermittent hypoxia (IH), and associated with cardiovascular diseases, such as stroke and heart failure. These cardiovascular diseases have a relation to atherosclerosis marked by the proliferation of vascular smooth muscle cells (VSMCs). In this study, we investigated the influence of IH on cultured rat aortic smooth muscle cell (RASMC). The proliferation of RASMC was significantly increased by IH without changing the level of apoptosis. In order to see what induces RASMC proliferation, we investigated the influence of normoxia (N)-, IH- and sustained hypoxia (SH)-treated cell conditioned media on RASMC proliferation. IH-treated cell conditioned medium significantly increased RASMC proliferation compared with N-treated cell conditioned medium, but SH-treated cell conditioned medium did not. We next investigated the epidermal growth factor (EGF) family as autocrine growth factors. Among the EGF family, we found significant increases in mRNAs for epiregulin (ER), amphiregulin (AR) and neuregulin-1 (NRG1) in IH-treated cells and mature ER in IH-treated cell conditioned medium. We next investigated the changes in erbB family receptors that are receptors for ER, AR and NRG1, and found that erbB2 receptor mRNA and protein expressions were increased by IH, but not by SH. Phosphorylation of erbB2 receptor at Tyr-1248 that mediates intracellular signaling for several physiological effects including cell proliferation was increased by IH, but not by SH. In addition, inhibitor for erbB2 receptor suppressed IH-induced cell proliferation. These results provide the first demonstration that IH induces VSMC proliferation, and suggest that EGF family, such as ER, AR and NRG1, and erbB2 receptor could be involved in the IH-induced VSMC proliferation. - Highlights: ●In vitro system for intermittent hypoxia (IH) and sustained hypoxia (SH). ●IH, but not SH, induces the proliferation of rat vascular smooth muscle cell. ●Epiregulin m

Intermittent hypoxia induces the proliferation of rat vascular smooth muscle cell with the increases in epidermal growth factor family and erbB2 receptor

Energy Technology Data Exchange (ETDEWEB)

Kyotani, Yoji, E-mail: cd147@naramed-u.ac.jp [Department of Pharmacology, Nara Medical University School of Medicine, Kashihara 634-8521 (Japan); Department of Pharmacy, Nara Medical University Hospital, Kashihara 634-8522 (Japan); Ota, Hiroyo [Second Department of Internal Medicine, Nara Medical University School of Medicine, Kashihara 634-8522 (Japan); Department of Biochemistry, Nara Medical University School of Medicine, Kashihara 634-8521 (Japan); Itaya-Hironaka, Asako; Yamauchi, Akiyo; Sakuramoto-Tsuchida, Sumiyo [Department of Biochemistry, Nara Medical University School of Medicine, Kashihara 634-8521 (Japan); Zhao, Jing; Ozawa, Kentaro; Nagayama, Kosuke; Ito, Satoyasu [Department of Pharmacology, Nara Medical University School of Medicine, Kashihara 634-8521 (Japan); Takasawa, Shin [Department of Biochemistry, Nara Medical University School of Medicine, Kashihara 634-8521 (Japan); Kimura, Hiroshi [Second Department of Internal Medicine, Nara Medical University School of Medicine, Kashihara 634-8522 (Japan); Uno, Masayuki [Department of Pharmacy, Nara Medical University Hospital, Kashihara 634-8522 (Japan); Yoshizumi, Masanori [Department of Pharmacology, Nara Medical University School of Medicine, Kashihara 634-8521 (Japan)

2013-11-15

Obstructive sleep apnea is characterized by intermittent hypoxia (IH), and associated with cardiovascular diseases, such as stroke and heart failure. These cardiovascular diseases have a relation to atherosclerosis marked by the proliferation of vascular smooth muscle cells (VSMCs). In this study, we investigated the influence of IH on cultured rat aortic smooth muscle cell (RASMC). The proliferation of RASMC was significantly increased by IH without changing the level of apoptosis. In order to see what induces RASMC proliferation, we investigated the influence of normoxia (N)-, IH- and sustained hypoxia (SH)-treated cell conditioned media on RASMC proliferation. IH-treated cell conditioned medium significantly increased RASMC proliferation compared with N-treated cell conditioned medium, but SH-treated cell conditioned medium did not. We next investigated the epidermal growth factor (EGF) family as autocrine growth factors. Among the EGF family, we found significant increases in mRNAs for epiregulin (ER), amphiregulin (AR) and neuregulin-1 (NRG1) in IH-treated cells and mature ER in IH-treated cell conditioned medium. We next investigated the changes in erbB family receptors that are receptors for ER, AR and NRG1, and found that erbB2 receptor mRNA and protein expressions were increased by IH, but not by SH. Phosphorylation of erbB2 receptor at Tyr-1248 that mediates intracellular signaling for several physiological effects including cell proliferation was increased by IH, but not by SH. In addition, inhibitor for erbB2 receptor suppressed IH-induced cell proliferation. These results provide the first demonstration that IH induces VSMC proliferation, and suggest that EGF family, such as ER, AR and NRG1, and erbB2 receptor could be involved in the IH-induced VSMC proliferation. - Highlights: ●In vitro system for intermittent hypoxia (IH) and sustained hypoxia (SH). ●IH, but not SH, induces the proliferation of rat vascular smooth muscle cell. ●Epiregulin m

Effect of hypertensive rat plasma on ion transport of cultured vascular smooth muscle

International Nuclear Information System (INIS)

Magargal, W.W.; Overbeck, H.W.

1986-01-01

We layered fresh, unprocessed plasma from healthy rats with early (less than or equal to 7 days) or benign, chronic (greater than 3 wk) one-kidney, one-clip hypertension and from paired one-kidney normotensive control rats over confluent primary-cultured rat aortic smooth muscle cells. Plasma from all rats increased cellular ouabain-sensitive 86 Rb + uptake and sodium content and decreased ouabain-insensitive 86 Rb + uptake compared with uptakes and content in the presence of balanced salt solution (P less than 0.01). Cells incubated in the presence of plasma from rats with early (P less than 0.02) or chronic hypertension (P less than 0.01) had significantly reduced ouabain-sensitive 86 Rb + uptake when compared with cells incubated in normotensive plasma, but their intracellular Na+ contents were not lower. We no longer detected this uptake difference when chronic hypertensives drank 0.9% NaCl instead of water. Plasma from hypertensive rats also altered ouabain-insensitive 86 Rb + uptake by the cultured cells. These findings of this new, reproducible, and specific assay system support the hypothesis that plasma factors inhibit the membrane sodium-potassium pump in vascular smooth muscle cells in this form of hypertension. The abnormality occurs in both early and chronic stages, but may not be related to sodium intake. The data also provide evidence for plasma factors in hypertension altering membrane K+ permeability

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

Science.gov (United States)

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

2014-01-01

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

The ability of AIF-1 to activate human vascular smooth muscle cells is lost by mutations in the EF-hand calcium-binding region

International Nuclear Information System (INIS)

Autieri, Michael V.; Chen Xing

2005-01-01

Allograft Inflammatory Factor-1 (AIF-1) is a cytoplasmic calcium-binding protein expressed in vascular smooth muscle cells (VSMC) in response to injury or cytokine stimulation. AIF-1 contains a partially conserved EF-hand calcium-binding domain, and participates in VSMC activation by activation of Rac1 and induction of Granulocyte-Colony Stimulating Factor (G-CSF) expression; however, the mechanism whereby AIF-1 mediates these effects is presently uncharacterized. To determine if calcium binding plays a functional role in AIF-1 activity, a single site-specific mutation was made in the EF-hand calcium-binding domain to abrogate binding of calcium (AIF-1ΔA), which was confirmed by calcium overlay. Functionally, similar to wild-type AIF-1, AIF-1ΔA was able to polymerize F-actin in vitro. However, in contrast to wild-type AIF-1, over-expression of AIF-1ΔA was unable to increase migration or proliferation of primary human VSMC. Further, it was unable to activate Rac1, or induce G-CSF expression to the degree as wild-type AIF-1. Taken together, modification of the wild-type EF-hand domain and native calcium-binding activity results in a loss of AIF-1 function. We conclude that appropriate calcium-binding potential is critical in AIF-1-mediated effects on VSMC pathophysiology, and that AIF-1 activity is mediated by Rac1 activation and G-CSF expression

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

Science.gov (United States)

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

2011-01-01

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

Down-regulation of endothelin binding sites in rat vascular smooth muscle cells

International Nuclear Information System (INIS)

Roubert, P.; Gillard, V.; Plas, P.; Chabrier, P.E.; Braquet, P.

1990-01-01

In cultured rat aortic smooth muscle cells, [ 125 I]endothelin (ET-1) bound to an apparent single class of high affinity recognition sites with a dissociation constant of 1.84 +/- 0.29 nmol/L and a maximum binding of 62 +/- 10.5 fmol/10(6) cells. The binding was not affected by calcium antagonists or vasoactive substances, including angiotensin II, arginine vasopressin, atrial natriuretic factor and bradykinin. Exposure of the cells to ET-1 (0.01 nmol/L to 10 nmol/L) resulted in an apparent dose-dependent reduction of the number of endothelin binding sites with no significant modification of its binding affinity. The time course of the down-regulation of ET-1 binding sites showed that this effect was present after 30 min incubation and persisted after 18 h. This indicates that down-regulation of ET-1 binding sites can modulate the activity of ET-1 and suggests a rapid internalization of ET-1 in vascular cells

Effects of ouabain on vascular reactivity

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Vassallo D.V.

1997-04-01

Full Text Available Ouabain is an endogenous substance occurring in the plasma in the nanomolar range, that has been proposed to increase vascular resistance and induce hypertension. This substance acts on the a-subunit of Na+,K+-ATPase inhibiting the Na+-pump activity. In the vascular smooth muscle this effect leads to intracellular Na+ accumulation that reduces the activity of the Na+/Ca2+ exchanger and to an increased vascular tone. It was also suggested that circulating ouabain, even in the nanomolar range, sensitizes the vascular smooth muscle to vasopressor substances. We tested the latter hypothesis by studying the effects of ouabain in the micromolar and nanomolar range on phenylephrine (PE-evoked pressor responses. The experiments were performed in normotensive and hypertensive rats in vivo, under anesthesia, and in perfused rat tail vascular beds. The results showed that ouabain pretreatment increased the vasopressor responses to PE in vitro and in vivo. This sensitization after ouabain treatment was also observed in hypertensive animals which presented an enhanced vasopressor response to PE in comparison to normotensive animals. It is suggested that ouabain at nanomolar concentrations can sensitize vascular smooth muscle to vasopressor stimuli possibly contributing to increased tone in hypertension

The influence of perivascular adipose tissue on vascular homeostasis

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Szasz T

2013-03-01

Full Text Available Theodora Szasz,1 Gisele Facholi Bomfim,2 R Clinton Webb1 1Department of Physiology, Georgia Regents University, Augusta, USA; 2Department of Pharmacology, University of São Paulo, São Paulo, Brazil Abstract: The perivascular adipose tissue (PVAT is now recognized as an active contributor to vascular function. Adipocytes and stromal cells contained within PVAT are a source of an ever-growing list of molecules with varied paracrine effects on the underlying smooth muscle and endothelial cells, including adipokines, cytokines, reactive oxygen species, and gaseous compounds. Their secretion is regulated by systemic or local cues and modulates complex processes, including vascular contraction and relaxation, smooth muscle cell proliferation and migration, and vascular inflammation. Recent evidence demonstrates that metabolic and cardiovascular diseases alter the morphological and secretory characteristics of PVAT, with notable consequences. In obesity and diabetes, the expanded PVAT contributes to vascular insulin resistance. PVAT-derived cytokines may influence key steps of atherogenesis. The physiological anticontractile effect of PVAT is severely diminished in hypertension. Above all, a common denominator of the PVAT dysfunction in all these conditions is the immune cell infiltration, which triggers the subsequent inflammation, oxidative stress, and hypoxic processes to promote vascular dysfunction. In this review, we discuss the currently known mechanisms by which the PVAT influences blood vessel function. The important discoveries in the study of PVAT that have been made in recent years need to be further advanced, to identify the mechanisms of the anticontractile effects of PVAT, to explore the vascular-bed and species differences in PVAT function, to understand the regulation of PVAT secretion of mediators, and finally, to uncover ways to ameliorate cardiovascular disease by targeting therapeutic approaches to PVAT. Keywords: adipokines

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

International Nuclear Information System (INIS)

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

2011-01-01

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

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.

Role of blood and vascular smooth muscle in the vasoactivity of nitrite

Science.gov (United States)

Liu, Taiming; Schroeder, Hobe J.; Barcelo, Lisa; Bragg, Shannon L.; Terry, Michael H.; Wilson, Sean M.; Power, Gordon G.

2014-01-01

Recent evidence from humans and rats indicates that nitrite is a vasodilator under hypoxic conditions by reacting with metal-containing proteins to produce nitric oxide (NO). We tested the hypothesis that near-physiological concentrations of nitrite would produce vasodilation in a hypoxia- and concentration-dependent manner in the hind limb of sheep. Anesthetized sheep were instrumented to measure arterial blood pressure and femoral blood flows continuously in both hind limbs. Nitrite was infused into one femoral artery to raise the nitrite concentration in the femoral vein by 10 to 15-fold while the sheep breathed 50%, 14% or 12% oxygen in inspired air. In contrast to reports in humans and rats, the nitrite infusion had no measurable effect on mean femoral blood flows or vascular conductances, regardless of inspired O2 levels. In vitro experiments showed no significant difference in the release of NO from nitrite in sheep and human red blood cells. Further experiments demonstrated nitrite is converted to NO in rat artery homogenates faster than sheep arteries, and that this source of NO production is attenuated in the presence of a heme oxidizer. Finally, western blots indicate that concentrations of the heme-containing protein cytoglobin, but not myoglobin, are markedly lower in sheep arteries compared with rats. Overall, the results demonstrate that nitrite is not a physiological vasodilator in sheep. This is likely due to a lack of conversion of nitrite to NO within the vascular smooth muscle, perhaps due to deficient amounts of the heme-containing protein cytoglobin. PMID:25108012

Functional role of stromal interaction molecule 1 (STIM1) in vascular smooth muscle cells

International Nuclear Information System (INIS)

Takahashi, Yoichiro; Watanabe, Hiroyuki; Murakami, Manabu; Ono, Kyoichi; Munehisa, Yoshiko; Koyama, Takashi; Nobori, Kiyoshi; Iijima, Toshihiko; Ito, Hiroshi

2007-01-01

We investigated the functional role of STIM1, a Ca 2+ sensor in the endoplasmic reticulum (ER) that regulates store-operated Ca 2+ entry (SOCE), in vascular smooth muscle cells (VSMCs). STIM1 was mainly localized at the ER and plasma membrane. The knockdown of STIM1 expression by small interfering (si) RNA drastically decreased SOCE. In contrast, an EF-hand mutant of STIM1, STIM1 E87A , produced a marked increase in SOCE, which was abolished by co-transfection with siRNA to transient receptor potential canonical 1 (TRPC1). In addition, transfection with siRNA against STIM1 suppressed phosphorylation of cAMP-responsive element binding protein (CREB) and cell growth. These results suggest that STIM1 is an essential component of SOCE and that it is involved in VSMC proliferation

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.

The LOX-1 Scavenger Receptor and Its Implications in the Treatment of Vascular Disease

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M. W Twigg

2012-01-01

Full Text Available Cardiovascular disease is the leading cause of death. The disease is due to atherosclerosis which is characterized by lipid and fat accumulation in arterial blood vessel walls. A key causative event is the accumulation of oxidised low density lipoprotein particles within vascular cells, and this is mediated by scavenger receptors. One such molecule is the LOX-1 scavenger receptor that is expressed on endothelial, vascular smooth muscle, and lymphoid cells including macrophages. LOX-1 interaction with OxLDL particles stimulates atherosclerosis. LOX-1 mediates OxLDL endocytosis via a clathrin-independent internalization pathway. Transgenic animal model studies show that LOX-1 plays a significant role in atherosclerotic plaque initiation and progression. Administration of LOX-1 antibodies in cellular and animal models suggest that such intervention inhibits atherosclerosis. Antiatherogenic strategies that target LOX-1 function using gene therapy or small molecule inhibitors would be new ways to address the increasing incidence of vascular disease in many countries.

Inhibition of Proliferation of Vascular Smooth Muscle Cells by Cucurbitanes from Momordica charantia.

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Tuan, Nguyen Quoc; Lee, Do-Hyung; Oh, Joonseok; Kim, Chung Sub; Heo, Kyung-Sun; Myung, Chang-Seon; Na, MinKyun

2017-07-28

The cucurbitaceous plant Momordica charantia L., named "bitter melon", inhabits Asia, Africa, and South America and has been used as a traditional medicine. The atypical proliferation of vascular smooth muscle cells (VSMCs) plays an important role in triggering the pathogenesis of cardiovascular diseases. Platelet-derived growth factor (PDGF) is regarded as the most powerful growth factor in promoting the intimal accumulation of VSMCs. The current study features the identification of six new cucurbitane-type triterpenoids (1-6) from the fruits of M.  charantia, utilizing diverse chromatographic and spectroscopic techniques. In particular, the 2D structure of 1 was confirmed utilizing the long-range HSQMBC NMR pulse, capable of measuring heteronuclear long-range correlations ( 4-6 J CH ). The cucurbitanes were also assessed for their inhibitory activity against PDGF-induced VSMC proliferation. This current study may constitute a basis for developing those chemotypes into sensible pharmacophores alleviating cardiovascular disorders.

Microparticle Shedding by Erythrocytes, Monocytes and Vascular Smooth Muscular Cells Is Reduced by Aspirin in Diabetic Patients.

Science.gov (United States)

Chiva-Blanch, Gemma; Suades, Rosa; Padró, Teresa; Vilahur, Gemma; Peña, Esther; Ybarra, Juan; Pou, Jose M; Badimon, Lina

2016-07-01

Diabetes mellitus is associated with an enhanced risk for cardiovascular disease and its prevalence is increasing. Diabetes induces metabolic stress on blood and vascular cells, promoting platelet activation and vascular dysfunction. The level of vascular cell activation can be measured by the number and phenotype of microparticles found in the circulation. The aim of this study was to investigate the effect of a platelet-inhibitory dose of aspirin on the number and type of microparticles shed to the circulation. Forty-three diabetic patients were enrolled in the study and received a daily dose of 100mg of aspirin for 10 days to cover the average platelet life-span in the circulation. Before and after the intervention period, circulating microparticles were characterized and quantified by flow cytometry. Type 1 diabetic patients had about twice the number of tissue factor-positive circulating microparticles (derived both from platelets and monocytes) and endothelial-derived E-selectin positive microparticles than type 2 diabetic patients. Aspirin therapy significantly inhibited platelets since cyclooxygenase 1 derived thromboxane generation levels were reduced by 99%. Microparticles derived from erythrocytes, activated monocytes, and smooth muscle cells were significantly reduced after 10 days of aspirin administration. These results indicate that: a) vascular and blood cells in type 1 diabetic patients are exposed to more sustained stress shown by their specific microparticle origin and levels; b) aspirin therapy inhibits vascular wall cell activation and microparticle shedding, and c) the effects of aspirin are similar in type 1 and 2 diabetes. Copyright © 2016 Sociedad Española de Cardiología. Published by Elsevier España, S.L.U. All rights reserved.

LPS, but not Angiotensin ll, lnduces Direct Pro-lnflammatory Effects in Cultured Mouse Arteries and Human Endothelial and Vascular Smooth Muscle Cells

DEFF Research Database (Denmark)

Outzen, Emilie M; Zaki, Marina; Mehryar, Rahila

2017-01-01

resistance-sized arteries (MRA) supported by experiments in cultured human primary endothelial and vascular smooth muscle cells. Results showed that 24-hr organ culture of mouse MRA with 10 nM Ang II had, unlike 100 ng/mL LPS, no effects on IL-6 or MCP-1 secretion, VCAM1 mRNA expression or endothelial......]-Ang II had no concentration- or time-dependent effects on IL-6 and MCP-1 secretion in human umbilical vein endothelial cells (HUVEC) and human aortic smooth muscle cells (HASMC). AGTR1 or AGTR2 mRNA expression were undetectable in HUVEC, whereas HASMC expressed only AGTR1 mRNA. In summary, contrary...... rights reserved....

Technetium-99m labeled antisense probes uptake in vascular smooth muscle cells

International Nuclear Information System (INIS)

Zhang, Y.X.; Qin, G.M.; An, R.; Cao, G.X.; Cao, W.; Gao, Z.R.

2002-01-01

In the arterial wall, smooth muscle cells (SMC) normally exist in a quiescent, differentiated state, representing the contractile phenotype. During the development of atherosclerosis SMC change towards the synthetic phenotype going along with proliferation, chemotactic response and increased monocyte binding. 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. The atherosclerotic plaques contained 3-4 fold more c-myc mRNA than those in the normal aortic arteries, while increased Bax and Bak coupled with lack/paucity of Bcl-2 and Bcl-xL are associated with SMC apoptosis in advanced lesions. Methods: 1 Oligonucleotide Conjugation: A solution of single stranded amine-derivatized DNA (100-1000μg) was prepared at a concentration of 2 mg/ml in 0.25M sodium bicarbonate, 1 M sodium chloride, 1mM EDTA, pH8.5. Cell uptake studies: 99m Tc- MAG 3 -DNA radioactivity incorporation into porcine coronary smooth muscle cells in the log and plateau phases, respectively, was determined after different times of incubation at 37. The influence of extracellular 99m Tc- MAG 3 -DNA concentration on SMC uptake was also analyzed. [Results] Essentially complete conjugation was achieved by reverse-phase Sep-Pak C18 chromatography analysis. The MAG 3 -DNA was labeled with 99m Tc at room temperature and neutral pH, with a mean labeling efficiency of 80.11%(s.d=2.96%,n=4). The labeled antisense DNA still remained the ability to hybridize with its complementary DNA. After labeling, the stability of the DNA in saline or serum was retained as determined by reverse-phase Sep-Pak C18 chromatography analysis, except a shift at 30 min in serum incubation that suggesting a short time serum protein binding. 99m Tc-MAG 3 -c-myc uptake plateaued at 60 min and was directly proportional to the

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

Science.gov (United States)

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

2016-07-01

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

SREBP inhibits VEGF expression in human smooth muscle cells

Energy Technology Data Exchange (ETDEWEB)

Motoyama, Koka [Metabolism, Endocrinology and Molecular Medicine, Osaka City University Graduate School of Medicine, Osaka (Japan); Fukumoto, Shinya [Metabolism, Endocrinology and Molecular Medicine, Osaka City University Graduate School of Medicine, Osaka (Japan); Koyama, Hidenori [Metabolism, Endocrinology and Molecular Medicine, Osaka City University Graduate School of Medicine, Osaka (Japan); Emoto, Masanori [Metabolism, Endocrinology and Molecular Medicine, Osaka City University Graduate School of Medicine, Osaka (Japan); Shimano, Hitoshi [Department of Internal Medicine, Institute of Clinical Medicine, University of Tsukuba, Ibaraki (Japan); Maemura, Koji [Department of Cardiovascular Medicine, Graduate School of Medicine, University of Tokyo, Tokyo (Japan); Nishizawa, Yoshiki [Metabolism, Endocrinology and Molecular Medicine, Osaka City University Graduate School of Medicine, Osaka (Japan)

2006-03-31

Sterol regulatory element-binding proteins (SREBPs) are transcription factors that regulate expression of genes encoding enzymes for lipid biosynthesis. SREBPs are activated by HMG-CoA reductase inhibitors (statins). Statins have been also reported to suppress vascular endothelial growth factor (VEGF) expression in vascular smooth muscle cells (VSMCs). Therefore, we hypothesized that SREBPs are involved in statin-mediated regulation of VEGF production in VSMCs. SREBP1 was robustly expressed, and was activated by atorvastatin in VSMCs, as demonstrated by increased levels of the mature nuclear form of SREBP1, and increased promoter activities of a reporter containing sterol regulatory elements by atorvastatin. Moreover, overexpression of SREBP1a dose-dependently suppressed VEGF promoter activity. Site-specific mutation or deletion of the proximal Sp1 sites reduced the inhibitory effects of SREBP1a on VEGF promoter activity. These data demonstrated that SREBP1, activated by atorvastatin, suppressed VEGF expression through the indirect interaction with the proximal tandem Sp1 sites in VSMCs.

SREBP inhibits VEGF expression in human smooth muscle cells

International Nuclear Information System (INIS)

Motoyama, Koka; Fukumoto, Shinya; Koyama, Hidenori; Emoto, Masanori; Shimano, Hitoshi; Maemura, Koji; Nishizawa, Yoshiki

2006-01-01

Sterol regulatory element-binding proteins (SREBPs) are transcription factors that regulate expression of genes encoding enzymes for lipid biosynthesis. SREBPs are activated by HMG-CoA reductase inhibitors (statins). Statins have been also reported to suppress vascular endothelial growth factor (VEGF) expression in vascular smooth muscle cells (VSMCs). Therefore, we hypothesized that SREBPs are involved in statin-mediated regulation of VEGF production in VSMCs. SREBP1 was robustly expressed, and was activated by atorvastatin in VSMCs, as demonstrated by increased levels of the mature nuclear form of SREBP1, and increased promoter activities of a reporter containing sterol regulatory elements by atorvastatin. Moreover, overexpression of SREBP1a dose-dependently suppressed VEGF promoter activity. Site-specific mutation or deletion of the proximal Sp1 sites reduced the inhibitory effects of SREBP1a on VEGF promoter activity. These data demonstrated that SREBP1, activated by atorvastatin, suppressed VEGF expression through the indirect interaction with the proximal tandem Sp1 sites in VSMCs

A key role for the endothelium in NOD1 mediated vascular inflammation: comparison to TLR4 responses.

Directory of Open Access Journals (Sweden)

Timothy Gatheral

Full Text Available Understanding the mechanisms by which pathogens induce vascular inflammation and dysfunction may reveal novel therapeutic targets in sepsis and related conditions. The intracellular receptor NOD1 recognises peptidoglycan which features in the cell wall of gram negative and some gram positive bacteria. NOD1 engagement generates an inflammatory response via activation of NFκB and MAPK pathways. We have previously shown that stimulation of NOD1 directly activates blood vessels and causes experimental shock in vivo. In this study we have used an ex vivo vessel-organ culture model to characterise the relative contribution of the endothelium in the response of blood vessels to NOD1 agonists. In addition we present the novel finding that NOD1 directly activates human blood vessels. Using human cultured cells we confirm that endothelial cells respond more avidly to NOD1 agonists than vascular smooth muscle cells. Accordingly we have sought to pharmacologically differentiate NOD1 and TLR4 mediated signalling pathways in human endothelial cells, focussing on TAK1, NFκB and p38 MAPK. In addition we profile novel inhibitors of RIP2 and NOD1 itself, which specifically inhibit NOD1 ligand induced inflammatory signalling in the vasculature. This paper is the first to demonstrate activation of whole human artery by NOD1 stimulation and the relative importance of the endothelium in the sensing of NOD1 ligands by vessels. This data supports the potential utility of NOD1 and RIP2 as therapeutic targets in human disease where vascular inflammation is a clinical feature, such as in sepsis and septic shock.

Specialized mouse embryonic stem cells for studying vascular development.

Science.gov (United States)

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

2014-01-01

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

Nuclear import mechanism for myocardin family members and their correlation with vascular smooth muscle cell phenotype.

Science.gov (United States)

Nakamura, Seiji; Hayashi, Ken'ichiro; Iwasaki, Kazuhiro; Fujioka, Tomoaki; Egusa, Hiroshi; Yatani, Hirofumi; Sobue, Kenji

2010-11-26

Myocardin (Mycd), which is essential for the differentiation of the smooth muscle cell lineage, is constitutively located in the nucleus, although its family members, myocardin-related transcription factors A and B (MRTF-A/B), mostly reside in the cytoplasm and translocate to the nucleus in response to Rho signaling. The mechanism for their nuclear import is unclear. Here we investigated the mechanism for the nuclear import of Mycd family members and demonstrated any correlation between such mechanism and the phenotype of vascular smooth muscle cells (VSMCs). In cultured VSMCs, the knockdown of importin β1 inhibited the nuclear import of Mycd and MRTF-A/B. Their NH(2)-terminal basic domain was identified as a binding site for importin α/β1 by in vitro analyses. However, Mycd had a higher affinity for importin α/β1 than did MRTF-A/B, even in the absence of G-actin, and Mycd affinity for importin α1/β1 was stronger than for any other importin α/β1 heterodimers. The binding of Mycd to importin α/β1 was insensitive to G-actin, whereas that of MRTF-A/B was differently inhibited by G-actin. In dedifferentiated VSMCs, the levels of importins α1 and β1 were reduced concomitant with down-regulation of Mycd, serum response factor, and smooth muscle cell markers. By contrast, in differentiated VSMCs, their expressions were up-regulated. Thus, the nuclear import of Mycd family members in VSMCs depends on importin α/β1, and their relative affinities for importin α/β1 heterodimers determine Mycd nuclear import. The expression of Mycd nuclear import machineries is related to the expression levels of VSMC phenotype-dependent smooth muscle cell markers.

Vascular Smooth Muscle Cells From Hypertensive Patient-Derived Induced Pluripotent Stem Cells to Advance Hypertension Pharmacogenomics.

Science.gov (United States)

Biel, Nikolett M; Santostefano, Katherine E; DiVita, Bayli B; El Rouby, Nihal; Carrasquilla, Santiago D; Simmons, Chelsey; Nakanishi, Mahito; Cooper-DeHoff, Rhonda M; Johnson, Julie A; Terada, Naohiro

2015-12-01

Studies in hypertension (HTN) pharmacogenomics seek to identify genetic sources of variable antihypertensive drug response. Genetic association studies have detected single-nucleotide polymorphisms (SNPs) that link to drug responses; however, to understand mechanisms underlying how genetic traits alter drug responses, a biological interface is needed. Patient-derived induced pluripotent stem cells (iPSCs) provide a potential source for studying otherwise inaccessible tissues that may be important to antihypertensive drug response. The present study established multiple iPSC lines from an HTN pharmacogenomics cohort. We demonstrated that established HTN iPSCs can robustly and reproducibly differentiate into functional vascular smooth muscle cells (VSMCs), a cell type most relevant to vasculature tone control. Moreover, a sensitive traction force microscopy assay demonstrated that iPSC-derived VSMCs show a quantitative contractile response on physiological stimulus of endothelin-1. Furthermore, the inflammatory chemokine tumor necrosis factor α induced a typical VSMC response in iPSC-derived VSMCs. These studies pave the way for a large research initiative to decode biological significance of identified SNPs in hypertension pharmacogenomics. Treatment of hypertension remains suboptimal, and a pharmacogenomics approach seeks to identify genetic biomarkers that could be used to guide treatment decisions; however, it is important to understand the biological underpinnings of genetic associations. Mouse models do not accurately recapitulate individual patient responses based on their genetics, and hypertension-relevant cells are difficult to obtain from patients. Induced pluripotent stem cell (iPSC) technology provides a great interface to bring patient cells with their genomic data into the laboratory and to study hypertensive responses. As an initial step, the present study established an iPSC bank from patients with primary hypertension and demonstrated an effective

Reversal of sodium pump inhibitor induced vascular smooth muscle contraction with digibind. Stoichiometry and its implications.

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Krep, H H; Graves, S W; Price, D A; Lazarus, M; Ensign, A; Soszynski, P A; Hollenberg, N K

1996-01-01

The possibility that a circulating sodium pump inhibitor contributes to the pathogenesis of volume-dependent hypertension via an action on vascular smooth muscle (VSM) is supported by multiple lines of investigation, but remains controversial. We had two goals in this study. The first was to compare the pattern of contractile response of rabbit aorta induced by two candidates, ouabain and a labile sodium pump inhibitor that we have identified in the peritoneal dialysate of volume-expanded hypertensive patients with chronic renal failure. Our second goal was to examine the ability of Digibind, a Fab fragment of antisera directed against digoxin, to reverse VSM contraction induced by both agents. Ouabain induced a concentration-dependent contraction, which was delayed in onset, was gradual, and reached a stable plateau after many hours. The labile sodium pump inhibitor induced a qualitatively similar series of responses. Digibind rapidly reversed the contractile responses to both sodium pump inhibitors, with a rate of relaxation that matched that induced by physical removal of the pump inhibitor from the bath. For ouabain, the Digibind:ouabain stoichiometry was highly predictable. When Digibind was present in a molar concentration equivalent to that of ouabain, or less, it had no effect. When the Digibind concentration was twice that of ouabain, complete relaxation occurred. Although the concentration:VSM response relationship for ouabain was steep, the concentration:effect interaction with Digibind was even more steep. The molar concentration of Digibind required to reverse the effects of the labile endogenous inhibitor from peritoneal dialysate was consistently lower than that for ouabain, which is compatible with either greater potency of the labile factor in VSM or greater affinity for Digibind. These findings are compatible with a role for one or more endogenous sodium pump inhibitors as the determinant of vascular smooth muscle tone in the volume

Plasma-mediated vascular dysfunction in the reduced uterine perfusion pressure model of preeclampsia: a microvascular characterization.

LENUS (Irish Health Repository)

Walsh, Sarah K

2012-01-31

Preeclampsia is associated with widespread maternal vascular dysfunction, which is thought to be mediated by circulating factor(s). The aim of the study was to characterize vascular function in the reduced uterine perfusion pressure (RUPP) rat model of preeclampsia and to investigate the role of plasma factors in mediating any observed changes in vascular reactivity. Mean arterial blood pressure and vascular function were measured in RUPP and control rats. Mesenteric vessels from both virgin and pregnant rats were exposed for 1 hour or overnight to plasma from both RUPP and control rats and their vascular function assessed. RUPP rats were characterized by severe hypertension, restricted fetal growth, and reduced placental weight (P<0.001). Vasorelaxation was impaired in resistance vessels from RUPP compared with control rats (acetylcholine: R(max) 70+\\/-3 versus 92+\\/-1 [NP] and 93+\\/-3% [sham], P<0.01; bradykinin: 40+\\/-2 versus 62+\\/-2 [NP] and 59+\\/-4% [sham], P<0.001). Incubation of vessels from pregnant (but not virgin) animals with RUPP plasma overnight resulted in an attenuation of vasorelaxant responses (acetylcholine: 63+\\/-7 versus 86+\\/-2%, P<0.05; bradykinin: 35+\\/-5 versus 55+\\/-6%, P<0.001). The residual relaxant response in RUPP plasma-treated vessels was not further attenuated after treatment with N(omega)-nitro-l-arginine methyl ester (acetylcholine: 57+\\/-7 versus 63+\\/-7%, ns; bradykinin: 37+\\/-5 versus 35+\\/-5%, ns). The RUPP rat model is characterized by an impaired response to vasodilators which may be attributable to one or more circulating factors. This plasma-mediated endothelial dysfunction appears to be a pregnancy-dependent effect. Furthermore, nitric oxide-mediated vasorelaxation appears to be absent in RUPP plasma-treated vessels.

Time-Dependent Vascular Effects of Endocannabinoids Mediated by Peroxisome Proliferator-Activated Receptor Gamma (PPAR

Directory of Open Access Journals (Sweden)

Saoirse E. O'Sullivan

2009-01-01

Full Text Available The aim of the present study was to examine whether endocannabinoids cause PPAR-mediated vascular actions. Functional vascular studies were carried out in rat aortae. Anandamide and N-arachidonoyl-dopamine (NADA, but not palmitoylethanolamide, caused significant vasorelaxation over time (2 hours. Vasorelaxation to NADA, but not anandamide, was inhibited by CB1 receptor antagonism (AM251, 1 M, and vasorelaxation to both anandamide and NADA was inhibited by PPAR antagonism (GW9662, 1 M. Pharmacological inhibition of de novo protein synthesis, nitric oxide synthase, and super oxide dismutase abolished the responses to anandamide and NADA. Removal of the endothelium partly inhibited the vasorelaxant responses to anandamide and NADA. Inhibition of fatty acid amide hydrolase (URB597, 1 M inhibited the vasorelaxant response to NADA, but not anandamide. These data indicate that endocannabinoids cause time-dependent, PPAR-mediated vasorelaxation. Activation of PPAR in the vasculature may represent a novel mechanism by which endocannabinoids are involved in vascular regulation.

NAMPT and NAMPT-controlled NAD Metabolism in Vascular Repair.

Science.gov (United States)

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

2016-06-01

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

Expression profile and protein translation of TMEM16A in murine smooth muscle

DEFF Research Database (Denmark)

Davis, Alison J; Forrest, Abigail S; Jepps, Thomas Andrew

2010-01-01

Recently, overexpression of the genes TMEM16A and TMEM16B has been shown to produce currents qualitatively similar to native Ca(2+)-activated Cl(-) currents (I(ClCa)) in vascular smooth muscle. However, there is no information about this new gene family in vascular smooth muscle, where Cl(-) chan...

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.

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

Directory of Open Access Journals (Sweden)

Laura A Villalobos

2016-12-01

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

Inhibition of MAPK and PKC pathways by 60Co γ-radiation in cultured vascular smooth muscle cells

International Nuclear Information System (INIS)

Jia Guanghong; Ma Yexin; Xiao Jianming

2002-01-01

Objective: To investigate the signal transduction pathways inhibited by 60 Co γ-radiation in cultured vascular smooth muscle cells (VSMC). Methods: The cultured VSMC were irradiated with 60 Co γ-radiation of 3.5, 7.0 and 14 Gy respectively. VSMC proliferation was measured by 3 H-TdR incorporation, while PKC, MAPK activities were determined by radioactivity assay. Results: Proliferation of VSMC was inhibited by 7.0, 14 Gy 60 Co γ-irradiation and the activities of PKC, MAPK were decreased significantly. Conclusion: Inhibitory effect of 7.0, 14 Gy 60 Co γ-irradiation on proliferation of VSMC might be resulted from decrease of the activity of PKC, MAPK

Micropatterned coculture of vascular endothelial and smooth muscle cells on layered electrospun fibrous mats toward blood vessel engineering.

Science.gov (United States)

Li, Huinan; Liu, Yaowen; Lu, Jinfu; Wei, Jiaojun; Li, Xiaohong

2015-06-01

A major challenge in vascular engineering is the establishment of proper microenvironment to guide the spatial organization, growth, and extracellular matrix (ECM) productions of cells found in blood vessels. In the current study, micropatterned fibrous mats with distinct ridges and grooves of different width were created to load smooth muscle cells (SMCs), which were assembled by stacking on vascular endothelial cell (EC)-loaded flat fibrous mats to mimic the in vivo-like organized structure of blood vessels. SMCs were mainly distributed in the ridges, and aligned fibers in the patterned regions led to the formation of elongated cell bodies, intense actin filaments, and expressions of collagen I and α-smooth muscle actin in a parallel direction with fibers. ECs spread over the flat fibrous mats and expressed collagen IV and laminin with a cobblestone-like feature. A z-stack scanning of fluorescently stained fibrous mats indicated that SMCs effectively infiltrated into fibrous scaffolds at the depth of around 200 μm. Compared with SMCs cultured alone, the coculture with ECs enhanced the proliferation, infiltration, and cytoskeleton elongation of SMCs on patterned fibrous mats. Although the coculture of SMCs made no significant difference in the EC growth, the coculture system on patterned fibrous scaffolds promoted ECM productions of both ECs and SMCs. Thus, this patterned fibrous configuration not only offers a promising technology in the design of tissue engineering scaffolds to construct blood vessels with durable mechanical properties, but also provides a platform for patterned coculture to investigate cell-matrix and cell-cell interactions in highly organized tissues. © 2014 Wiley Periodicals, Inc.

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

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Troy C Lund

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

Lung heparan sulfates modulate Kfc during increased vascular pressure: evidence for glycocalyx-mediated mechanotransduction

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Cluff, Mark; Kingston, Joseph; Hill, Denzil; Chen, Haiyan; Hoehne, Soeren; Malleske, Daniel T.; Kaur, Rajwinederjit

2012-01-01

Lung endothelial cells respond to changes in vascular pressure through mechanotransduction pathways that alter barrier function via non-Starling mechanism(s). Components of the endothelial glycocalyx have been shown to participate in mechanotransduction in vitro and in systemic vessels, but the glycocalyx's role in mechanosensing and pulmonary barrier function has not been characterized. Mechanotransduction pathways may represent novel targets for therapeutic intervention during states of elevated pulmonary pressure such as acute heart failure, fluid overload, and mechanical ventilation. Our objective was to assess the effects of increasing vascular pressure on whole lung filtration coefficient (Kfc) and characterize the role of endothelial heparan sulfates in mediating mechanotransduction and associated increases in Kfc. Isolated perfused rat lung preparation was used to measure Kfc in response to changes in vascular pressure in combination with superimposed changes in airway pressure. The roles of heparan sulfates, nitric oxide, and reactive oxygen species were investigated. Increases in capillary pressure altered Kfc in a nonlinear relationship, suggesting non-Starling mechanism(s). nitro-l-arginine methyl ester and heparanase III attenuated the effects of increased capillary pressure on Kfc, demonstrating active mechanotransduction leading to barrier dysfunction. The nitric oxide (NO) donor S-nitrosoglutathione exacerbated pressure-mediated increase in Kfc. Ventilation strategies altered lung NO concentration and the Kfc response to increases in vascular pressure. This is the first study to demonstrate a role for the glycocalyx in whole lung mechanotransduction and has important implications in understanding the regulation of vascular permeability in the context of vascular pressure, fluid status, and ventilation strategies. PMID:22160307

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

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

2018-04-01

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

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

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Philippe Boucher

2007-05-01

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

Inhibition of Vascular Smooth Muscle Growth via Signaling Crosstalk between AMP-Activated Protein Kinase and cAMP-Dependent Protein Kinase

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Joshua Daniel Stone

2012-10-01

Full Text Available Abnormal vascular smooth muscle (VSM growth is central in the pathophysiology of vascular disease yet fully effective therapies to curb this growth are lacking. Recent findings from our lab and others support growth control of VSM by adenosine monophosphate (AMP-based approaches including the metabolic sensor AMP-activated protein kinase (AMPK and cAMP-dependent protein kinase (PKA. Molecular crosstalk between AMPK and PKA has been previously suggested, yet the extent to which this occurs and its biological significance in VSM remains unclear. Considering their common AMP backbone and similar signaling characteristics, we hypothesized that crosstalk exists between AMPK and PKA in the regulation of VSM growth. Using rat primary VSM cells, the AMPK agonist AICAR increased AMPK activity and phosphorylation of the catalytic Thr172 site on AMPK. Interestingly, AICAR also phosphorylated a suspected PKA-inhibitory Ser485 site on AMPK, and these cumulative events were reversed by the PKA inhibitor PKI suggesting possible PKA-mediated regulation of AMPK. AICAR also increased PKA activity in a reversible fashion. The cAMP stimulator forskolin increased PKA activity and completely ameliorated Ser/Thr protein phosphatase-2C activity, suggesting a potential mechanism of AMPK modulation by PKA since inhibition of PKA by PKI reduced AMPK activity. Functionally, AMPK inhibited serum-stimulated cell cycle progression and cellular proliferation; however, PKA failed to do so. Moreover, AMPK and PKA reduced PDGF-β-stimulated VSM cell migration. Collectively, these results show that AMPK is capable of reducing VSM growth in both anti-proliferative and anti-migratory fashions. Furthermore, these data suggest that AMPK may be modulated by PKA and that positive feedback may exist between these two systems. These findings reveal a discrete nexus between AMPK and PKA in VSM and provide basis for metabolically-directed targets in reducing pathologic VSM growth.

Transforming growth factor β inhibits platelet derived growth factor-induced vascular smooth muscle cell proliferation via Akt-independent, Smad-mediated cyclin D1 downregulation.

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Abel Martin-Garrido

Full Text Available In adult tissue, vascular smooth muscle cells (VSMCs exist in a differentiated phenotype, which is defined by the expression of contractile proteins and lack of proliferation. After vascular injury, VSMC adopt a synthetic phenotype associated with proliferation, migration and matrix secretion. The transition between phenotypes is a consequence of the extracellular environment, and in particular, is regulated by agonists such as the pro-differentiating cytokine transforming growth factor β (TGFβ and the pro-proliferative cytokine platelet derived growth factor (PDGF. In this study, we investigated the interplay between TGFβ and PDGF with respect to their ability to regulate VSMC proliferation. Stimulation of human aortic VSMC with TGFβ completely blocked proliferation induced by all isoforms of PDGF, as measured by DNA synthesis and total cell number. Mechanistically, PDGF-induced Cyclin D1 mRNA and protein expression was inhibited by TGFβ. TGFβ had no effect on PDGF activation of its receptor and ERK1/2, but inhibited Akt activation. However, constitutively active Akt did not reverse the inhibitory effect of TGFβ on Cyclin D1 expression even though inhibition of the proteasome blocked the effect of TGFβ. siRNA against Smad4 completely reversed the inhibitory effect of TGFβ on PDGF-induced Cyclin D1 expression and restored proliferation in response to PDGF. Moreover, siRNA against KLF5 prevented Cyclin D1 upregulation by PDGF and overexpression of KLF5 partially reversed TGFβ-induced inhibition of Cyclin D1 expression. Taken together, our results demonstrate that KLF5 is required for PDGF-induced Cyclin D1 expression, which is inhibited by TGFβ via a Smad dependent mechanism, resulting in arrest of VSMCs in the G1 phase of the cell cycle.

Transforming growth factor β inhibits platelet derived growth factor-induced vascular smooth muscle cell proliferation via Akt-independent, Smad-mediated cyclin D1 downregulation.

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Martin-Garrido, Abel; Williams, Holly C; Lee, Minyoung; Seidel-Rogol, Bonnie; Ci, Xinpei; Dong, Jin-Tang; Lassègue, Bernard; Martín, Alejandra San; Griendling, Kathy K

2013-01-01

In adult tissue, vascular smooth muscle cells (VSMCs) exist in a differentiated phenotype, which is defined by the expression of contractile proteins and lack of proliferation. After vascular injury, VSMC adopt a synthetic phenotype associated with proliferation, migration and matrix secretion. The transition between phenotypes is a consequence of the extracellular environment, and in particular, is regulated by agonists such as the pro-differentiating cytokine transforming growth factor β (TGFβ) and the pro-proliferative cytokine platelet derived growth factor (PDGF). In this study, we investigated the interplay between TGFβ and PDGF with respect to their ability to regulate VSMC proliferation. Stimulation of human aortic VSMC with TGFβ completely blocked proliferation induced by all isoforms of PDGF, as measured by DNA synthesis and total cell number. Mechanistically, PDGF-induced Cyclin D1 mRNA and protein expression was inhibited by TGFβ. TGFβ had no effect on PDGF activation of its receptor and ERK1/2, but inhibited Akt activation. However, constitutively active Akt did not reverse the inhibitory effect of TGFβ on Cyclin D1 expression even though inhibition of the proteasome blocked the effect of TGFβ. siRNA against Smad4 completely reversed the inhibitory effect of TGFβ on PDGF-induced Cyclin D1 expression and restored proliferation in response to PDGF. Moreover, siRNA against KLF5 prevented Cyclin D1 upregulation by PDGF and overexpression of KLF5 partially reversed TGFβ-induced inhibition of Cyclin D1 expression. Taken together, our results demonstrate that KLF5 is required for PDGF-induced Cyclin D1 expression, which is inhibited by TGFβ via a Smad dependent mechanism, resulting in arrest of VSMCs in the G1 phase of the cell cycle.

Lipid Metabolism in Vascular Smooth Muscle Cells Infuenced by HCMV Infection

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Lingfang Li

2016-10-01

Full Text Available Background: The present study was designed to observe the infection of human cytomegalovirus (HCMV to human vascular smooth muscle cells (VSMCs, and the effect of viral infection on lipid metabolism in VSMCs. Methods: The cytopathic effects were observed by inverted microscopy and viral infection were examined by electron microscopy and RT-PCR. The lipid metabolism related gene profiling of VSMCs after HCMV infection was assayed by cDNA assay and the abnormal expression of genes were validated by quantitative RT-PCR. The content of cholesterol in VSMCs after HCMV infection was assayed by cholesterol detection kit. Results: VSMCs showed obvious cytopathic effects after HCMV infection. Intact viral particles could be detected in VSMCs using electron microscope. By use of RT-PCR technology, IE gene of HCMV could be amplified from VSMCs. The expression of cell lipid metabolism related gene profiling showed obvious disorders. The expression levels of HMG-CoA synthase and HMG-CoA reductase after infection increased significantly. The cellular cholesterol content (µmol/106 cells was significantly higher than that of mock infected group at 72h post infection. Conclusion: HCMV can infect VSMCs and the infection can affect cellular lipid metabolism related gene expression, which get involved in the occurrence and development of atherosclerosis (AS.

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

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

2016-11-15

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

MiR-29b Downregulation Induces Phenotypic Modulation of Vascular Smooth Muscle Cells: Implication for Intracranial Aneurysm Formation and Progression to Rupture

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Liqian Sun

2017-01-01

Full Text Available Background/Aims: Our previous microarray results identified numerous microRNAs (miRNAs, including miR-29b, that were differentially expressed in the serum of intracranial aneurysm (IA patients. The current study aimed to investigate whether miR-29b downregulation in IA could promote the phenotypic modulation of vascular smooth muscle cells (VSMCs involved in the pathogenesis of aneurysm by activating ATG14-mediated autophagy. Methods: First, the levels of miR-29b and autophagy related genes (ATGs between IA patients and normal subjects were compared. Next, we modified the level of miR-29b via lentivirus particles in the VSMCs and examined the effects of miR-29b on proliferation, migration, and phenotypic modulation of VSMCs from a contractile phenotype to a synthetic phenotype, as well as the levels of autophagy. Finally, the binding of miR-29b to the 3’UTR of ATG14 mRNA and its effects on ATG14 expression were analysed by a luciferase reporter assay and Western blot, respectively. Results: The level of miR-29b was decreased, and autophagy markers were increased in the IA patients compared to that of the normal subjects. Knockdown of miR-29b significantly promoted VSMCs proliferation and migration and, more importantly, induced the phenotypic modulation associated with autophagy activation, whereas miR-29b overexpression showed the opposite effects. The luciferase reporter assay demonstrated that ATG14 was a functional target gene of miR-29b. Notably, knockdown of ATG14 by siRNA apparently abrogated miR-29b inhibition-mediated phenotypic modulation. Conclusion: Downregulation of miR-29b induced VSMCs phenotypic modulation by directly activating ATG14-mediated autophagy, which is associated with the formation, growth and rupture of IAs.

MiR-29b Downregulation Induces Phenotypic Modulation of Vascular Smooth Muscle Cells: Implication for Intracranial Aneurysm Formation and Progression to Rupture.

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Sun, Liqian; Zhao, Manman; Zhang, Jingbo; Lv, Ming; Li, Youxiang; Yang, Xinjian; Liu, Aihua; Wu, Zhongxue

2017-01-01

Our previous microarray results identified numerous microRNAs (miRNAs), including miR-29b, that were differentially expressed in the serum of intracranial aneurysm (IA) patients. The current study aimed to investigate whether miR-29b downregulation in IA could promote the phenotypic modulation of vascular smooth muscle cells (VSMCs) involved in the pathogenesis of aneurysm by activating ATG14-mediated autophagy. First, the levels of miR-29b and autophagy related genes (ATGs) between IA patients and normal subjects were compared. Next, we modified the level of miR-29b via lentivirus particles in the VSMCs and examined the effects of miR-29b on proliferation, migration, and phenotypic modulation of VSMCs from a contractile phenotype to a synthetic phenotype, as well as the levels of autophagy. Finally, the binding of miR-29b to the 3'UTR of ATG14 mRNA and its effects on ATG14 expression were analysed by a luciferase reporter assay and Western blot, respectively. The level of miR-29b was decreased, and autophagy markers were increased in the IA patients compared to that of the normal subjects. Knockdown of miR-29b significantly promoted VSMCs proliferation and migration and, more importantly, induced the phenotypic modulation associated with autophagy activation, whereas miR-29b overexpression showed the opposite effects. The luciferase reporter assay demonstrated that ATG14 was a functional target gene of miR-29b. Notably, knockdown of ATG14 by siRNA apparently abrogated miR-29b inhibition-mediated phenotypic modulation. Downregulation of miR-29b induced VSMCs phenotypic modulation by directly activating ATG14-mediated autophagy, which is associated with the formation, growth and rupture of IAs. © 2017 The Author(s) Published by S. Karger AG, Basel.

Vitamin D modulates tissue factor and protease-activated receptor 2 expression in vascular smooth muscle cells.

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Martinez-Moreno, Julio M; Herencia, Carmen; Montes de Oca, Addy; Muñoz-Castañeda, Juan R; Rodríguez-Ortiz, M Encarnación; Díaz-Tocados, Juan M; Peralbo-Santaella, Esther; Camargo, Antonio; Canalejo, Antonio; Rodriguez, Mariano; Velasco-Gimena, Francisco; Almaden, Yolanda

2016-03-01

Clinical and epidemiologic studies reveal an association between vitamin D deficiency and increased risk of cardiovascular disease. Because vascular smooth muscle cell (VSMC)-derived tissue factor (TF) is suggested to be critical for arterial thrombosis, we investigated whether the vitamin D molecules calcitriol and paricalcitol could reduce the expression of TF induced by the proinflammatory cytokine TNF-α in human aortic VSMCs. We found that, compared with controls, incubation with TNF-α increased TF expression and procoagulant activity in a NF-κB-dependent manner, as deduced from the increased nuclear translocation of nuclear factor κ-light-chain-enhancer of activated B cells protein 65 (p65-NF-κB) and direct interaction of NF-κB to the TF promoter. This was accompanied by the up-regulation of TF signaling mediator protease-activated receptor 2 (PAR-2) expression and by the down-regulation of vitamin D receptor expression in a miR-346-dependent way. However, addition of calcitriol or paricalcitol blunted the TNF-α-induced TF expression and activity (2.01 ± 0.24 and 1.32 ± 0.14 vs. 3.02 ± 0.39 pmol/mg protein, P < 0.05), which was associated with down-regulation of NF-κB signaling and PAR-2 expression, as well as with restored levels of vitamin D receptor and enhanced expression of TF pathway inhibitor. Our data suggest that inflammation promotes a prothrombotic state through the up-regulation of TF function in VSMCs and that the beneficial cardiovascular effects of vitamin D may be partially due to decreases in TF expression and its activity in VSMCs. © FASEB.

Vascular smooth muscle cell differentiation to an osteogenic phenotype involves matrix metalloproteinase-2 modulation by homocysteine.

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Liu, Tingjiao; Lin, Jinghan; Ju, Ting; Chu, Lei; Zhang, Liming

2015-08-01

Arterial calcification is common in vascular diseases and involves conversion of vascular smooth muscle cells (VSMCs) to an osteoblast phenotype. Clinical studies suggest that the development of atherosclerosis can be promoted by homocysteine (HCY), but the mechanisms remain unclear. Here, we determined whether increases in HCY levels lead to an increase in VSMC calcification and differentiation, and examined the role of an extracellular matrix remodeler, matrix metalloproteinase-2 (MMP-2). Rat VSMCs were exposed to calcification medium in the absence or presence of HCY (10, 100 or 200 μmol/L) or an MMP-2 inhibitor (10(-6) or 10(-5) mol/L). MTT assays were performed to determine the cytotoxicity of the MMP-2 inhibitor in calcification medium containing 200 μmol/L HCY. Calcification was assessed by measurements of calcium deposition and alkaline phosphatase (ALP) activity as well as von Kossa staining. Expression of osteocalcin, bone morphogenetic protein (BMP)-2, and osteopontin, and MMP-2 was determined by immunoblotting. Calcification medium induced osteogenic differentiation of VSMCs. HCY promoted calcification, increased osteocalcin and BMP-2 expression, and decreased expression of osteopontin. MMP-2 expression was increased by HCY in a dose-dependent manner in VSMCs exposed to both control and calcification medium. The MMP-2 inhibitor decreased the calcium content and ALP activity, and attenuated the osteoblastic phenotype of VSMCs. Vascular calcification and osteogenic differentiation of VSMCs were positively regulated by HCY through increased/restored MMP-2 expression, increased expression of calcification proteins, and decreased anti-calcification protein levels. In summary, MMP-2 inhibition may be a protective strategy against VSMC calcification.

PHYSICAL CONTACT BETWEEN HUMAN VASCULAR ENDOTHELIAL AND SMOOTH MUSCLE CELLS MODULATES CYTOSOLIC AND NUCLEAR CALCIUM HOMEOSTASIS.

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Hassan, Ghada S; Jacques, Danielle; D'Orleans-Juste, Pedro; Magder, Sheldon; Bkaily, Ghassan

2018-05-14

The interaction between vascular endothelial cells (VECs) and vascular smooth muscle cells (VSMCs) plays an important role in the modulation of vascular tone. There is however no information on whether direct physical communication regulates the intracellular calcium levels of human VECs (hVECs) and/or hVSMCs . Thus, the objective of the study is to verify whether co-culture of hVECs and hVSMCs modulates cytosolic ([Ca2+]c) and nuclear calcium ([Ca2+]n) levels via physical contact and/or factors released by both cell types. Quantitative 3D confocal microscopy for [Ca2+]c and [Ca2+]n measurement was performed in cultured hVECs or hVSMCs or in co-culture of hVECs-hVSMCs. Our results show that: 1) physical contact between hVECs-hVECs or hVSMCs-hVSMCs does not affect [Ca2+]c and [Ca2+]n in these two cell types; 2) physical contact between hVECs and hVSMCs induces a significant increase only of [Ca2+]n of hVECs without affecting the level of [Ca2+]c and [Ca2+]n of hVSMCs; and 3) preconditioned culture medium of hVECs or hVSMCs does not affect [Ca2+]c and [Ca2+]n of both types of cells. We concluded that physical contact between hVECs and hVSMCs only modulates [Ca2+]n in hVECs. The increase of [Ca2+]n in hVECs may modulate nuclear functions that are calcium dependent.

The flavonoid quercetin induces apoptosis and inhibits JNK activation in intimal vascular smooth muscle cells

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Perez-Vizcaino, Francisco; Bishop-Bailley, David; Lodi, Federica; Duarte, Juan; Cogolludo, Angel; Moreno, Laura; Bosca, Lisardo; Mitchell, Jane A.; Warner, Timothy D.

2006-01-01

Quercetin, the most abundant dietary flavonol, exerts vasodilator, anti-hypertensive, and anti-atherogenic effects and reduces the vascular remodelling associated with elevated blood pressure. Here, we have compared the effects of quercetin in intimal- and medial-type rat vascular smooth muscle cells (VSMC) in culture. After 48 h, quercetin reduced the viability of a polyclonal intimal-type cell line derived from neonatal aorta but not of a medial-type cell line derived from adult aorta. These differential effects were similar in both proliferating and quiescent VSMC. Quercetin also preferentially reduced the viability of intimal-type over medial-type VSMC in primary cultures derived from balloon-injured carotid arteries. The effects of quercetin on cell viability were mainly dependent upon induction of apoptosis, as demonstrated by nuclear condensation and fragmentation, and were unrelated to PPARγ, pro-oxidant effects or nitric oxide. The expression of MAPKs (ERK, p38, and JNK) and ERK phosphorylation were not different between intimal- and medial-type VSMC. p38 phosphorylation was negligible in both cell types. Medial-type showed a weak JNK phosphorylation while this was markedly increased in intimal-type cells. Quercetin reduced JNK phosphorylation but had no consistent effect on ERK phosphorylation. In conclusion, quercetin preferentially produced apoptosis in intimal-type compared to medial-type VSMC. This might play a role in the anti-atherogenic and anti-hypertensive effects of quercetin

Inhibition of NF-κB activity in rabbit vascular smooth muscle cells by lovastatin

International Nuclear Information System (INIS)

Luan Zhaoxia; Lan Xiaoli

2003-01-01

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 PDGF BB (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

Attenuation of chondrogenic transformation in vascular smooth muscle by dietary quercetin in the MGP-deficient mouse model.

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Kelly E Beazley

Full Text Available Cartilaginous metaplasia of vascular smooth muscle (VSM is characteristic for arterial calcification in diabetes and uremia and in the background of genetic alterations in matrix Gla protein (MGP. A better understanding of the molecular details of this process is critical for the development of novel therapeutic approaches to VSM transformation and arterial calcification.This study aimed to identify the effects of bioflavonoid quercetin on chondrogenic transformation and calcification of VSM in the MGP-null mouse model and upon TGF-β3 stimulation in vitro, and to characterize the associated alterations in cell signaling.Molecular analysis revealed activation of β-catenin signaling in cartilaginous metaplasia in Mgp-/- aortae in vivo and during chondrogenic transformation of VSMCs in vitro. Quercetin intercepted chondrogenic transformation of VSM and blocked activation of β-catenin both in vivo and in vitro. Although dietary quercetin drastically attenuated calcifying cartilaginous metaplasia in Mgp-/- animals, approximately one-half of total vascular calcium mineral remained as depositions along elastic lamellae.Quercetin is potent in preventing VSM chondrogenic transformation caused by diverse stimuli. Combined with the demonstrated efficiency of dietary quercetin in preventing ectopic chondrogenesis in the MGP-null vasculature, these findings indicate a potentially broad therapeutic applicability of this safe for human consumption bioflavonoid in the therapy of cardiovascular conditions linked to cartilaginous metaplasia of VSM. Elastocalcinosis is a major component of MGP-null vascular disease and is controlled by a mechanism different from chondrogenic transformation of VSM and not sensitive to quercetin.

Nitrate decreases xanthine oxidoreductase-mediated nitrite reductase activity and attenuates vascular and blood pressure responses to nitrite.

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Damacena-Angelis, Célio; Oliveira-Paula, Gustavo H; Pinheiro, Lucas C; Crevelin, Eduardo J; Portella, Rafael L; Moraes, Luiz Alberto B; Tanus-Santos, Jose E

2017-08-01

Nitrite and nitrate restore deficient endogenous nitric oxide (NO) production as they are converted back to NO, and therefore complement the classic enzymatic NO synthesis. Circulating nitrate and nitrite must cross membrane barriers to produce their effects and increased nitrate concentrations may attenuate the nitrite influx into cells, decreasing NO generation from nitrite. Moreover, xanthine oxidoreductase (XOR) mediates NO formation from nitrite and nitrate. However, no study has examined whether nitrate attenuates XOR-mediated NO generation from nitrite. We hypothesized that nitrate attenuates the vascular and blood pressure responses to nitrite either by interfering with nitrite influx into vascular tissue, or by competing with nitrite for XOR, thus inhibiting XOR-mediated NO generation. We used two independent vascular function assays in rats (aortic ring preparations and isolated mesenteric arterial bed perfusion) to examine the effects of sodium nitrate on the concentration-dependent responses to sodium nitrite. Both assays showed that nitrate attenuated the vascular responses to nitrite. Conversely, the aortic responses to the NO donor DETANONOate were not affected by sodium nitrate. Further confirming these results, we found that nitrate attenuated the acute blood pressure lowering effects of increasing doses of nitrite infused intravenously in freely moving rats. The possibility that nitrate could compete with nitrite and decrease nitrite influx into cells was tested by measuring the accumulation of nitrogen-15-labeled nitrite ( 15 N-nitrite) by aortic rings using ultra-performance liquid chromatography tandem mass-spectrometry (UPLC-MS/MS). Nitrate exerted no effect on aortic accumulation of 15 N-nitrite. Next, we used chemiluminescence-based NO detection to examine whether nitrate attenuates XOR-mediated nitrite reductase activity. Nitrate significantly shifted the Michaelis Menten saturation curve to the right, with a 3-fold increase in the

Vascular endothelin ET(B) receptor-mediated contraction requires phosphorylation of ERK1/2 proteins

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Luo, Guogang; Jamali, Roya; Cao, Yong-Xiao

2006-01-01

In cardiovascular diseases, endothelin type B (ET(B)) receptors in arterial smooth muscle cells are upregulated. The present study revealed that organ culture of rat mesenteric artery segments enhanced endothelin ET(B) receptor-mediated contraction paralleled with increase in the receptor mRNA an...

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

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Ae-Rang Hwang

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

Statin therapy exacerbates alcohol-induced constriction of cerebral arteries via modulation of ethanol-induced BK channel inhibition in vascular smooth muscle.

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Simakova, Maria N; Bisen, Shivantika; Dopico, Alex M; Bukiya, Anna N

2017-12-01

Statins constitute the most commonly prescribed drugs to decrease cholesterol (CLR). CLR is an important modulator of alcohol-induced cerebral artery constriction (AICAC). Using rats on a high CLR diet (2% CLR) we set to determine whether atorvastatin administration (10mg/kg daily for 18-23weeks) modified AICAC. Middle cerebral arteries were pressurized in vitro at 60mmHg and AICAC was evoked by 50mM ethanol, that is within the range of blood alcohol detected in humans following moderate-to-heavy drinking. AICAC was evident in high CLR+atorvastatin group but not in high CLR diet+placebo. Statin exacerbation of AICAC persisted in de-endothelialized arteries, and was blunted by CLR enrichment in vitro. Fluorescence imaging of filipin-stained arteries showed that atorvastatin decreased vascular smooth muscle (VSM) CLR when compared to placebo, this difference being reduced by CLR enrichment in vitro. Voltage- and calcium-gated potassium channels of large conductance (BK) are known VSM targets of ethanol, with their beta1 subunit being necessary for ethanol-induced channel inhibition and resulting AICAC. Ethanol-induced BK inhibition in excised membrane patches from freshly isolated myocytes was exacerbated in the high CLR diet+atorvastatin group when compared to high CLR diet+placebo. Unexpectedly, atorvastatin decreased the amount and function of BK beta1 subunit as documented by immunofluorescence imaging and functional patch-clamp studies. Atorvastatin exacerbation of ethanol-induced BK inhibition disappeared upon artery CLR enrichment in vitro. Our study demonstrates for the first time statin's ability to exacerbate the vascular effect of a widely consumed drug of abuse, this exacerbation being driven by statin modulation of ethanol-induced BK channel inhibition in the VSM via CLR-mediated mechanism. Copyright © 2017 Elsevier Inc. All rights reserved.

Synthesis and Protective Effects of Kaempferol-3'-sulfonate on Hydrogen Peroxide-induced injury in Vascular Smooth Muscle Cells.

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Yang, Xinbin; Wang, Qin; Wang, Chunmei; Qin, Xiaolin; Huang, Yu; Zeng, Renquan

2016-06-01

A novel water-soluble sulfated derivative, kaempferol-3'-sulfonate acid sodium (KS) with the composition of [C15 H9 O9 SNa]·2.5H2 O, was synthesized and characterized by elemental analysis, IR, (1) H NMR, (13) C NMR, and HRMS. Its protective effects on human vascular smooth muscle cells injured by hydrogen peroxide were evaluated by CCK-8 method, flow cytometry, and Western blotting. The experimental results indicated that the KS can significantly increase cell viability and reduce apoptosis on H2 O2 -injured VSMCs, as well as reverse the effects of H2 O2 on Bcl-2, Bad, and caspase-3 expressions. In addition, LDH leakage, MDA levels, and SOD and GSH activities were also measured with spectrophotometry. The results indicated that the KS acted as antioxidant preventing LDH leakage and MDA production, while increasing intracellular SOD and GSH activities. These findings revealed that KS might potentially serve as an effective antioxidant agent for prevention and treatment of vascular disease caused by H2 O2 -injured VSMCs. © 2015 John Wiley & Sons A/S.

Ouabain binding to cultured vascular smooth muscle cells of the spontaneously hypertensive rat

International Nuclear Information System (INIS)

Hopp, L.; Khalil, F.; Tamura, H.; Kino, M.; Searle, B.M.; Tokushige, A.; Aviv, A.

1986-01-01

The binding of ouabain and K + to the Na + pump were analyzed in serially passed cultured vascular smooth muscle cells (VSMCs) originating from spontaneously hypertensive (SH) Wistar-Kyoto (WKY), and American Wistar (W) rats. The techniques have utilized analyses of displacement of [ 3 H]ouabain by both unlabeled ouabain and K + from specific binding sites on the VSMCs. The authors have found that 1) each of the VSMC preparations from the three rat strains appeared to demonstrate one population of specific ouabain receptors (Na + pumps); 2) the number of Na + pump units of both the SH and WKY rats was significantly lower than the number of Na + pump units of W rat VSMCs; 3) the equilibrium dissociation constant values (μM) for ouabain in VSMCs of SH and WKY rats were similar but were significantly higher than that of VSMCs derived from W rats; and 4) among the VSMCs originating from the three rat strains, the apparent equilibrium dissociation constant value for K + (mM) was the lowest in those of the SH rat compared with VSMCs of the WKY rat and W rat. Previous studies have demonstrated increased passive Na + and K + transport rate constants of SH rat VSMCs compared with either W or WKY rat cells. These findings suggest the possibility of higher permeabilities of the SH cells. They propose that the combined effect of a low number of Na + pump units with higher permeabilities to Na + and K + predisposes VSMCs of the SH rat to disturbances in their cellular ionic regulation. These genetic defects, if they occur in vivo, may lead to an increase in the vascular tone

Comparison of MEK/ERK pathway inhibitors on the upregulation of vascular G-protein coupled receptors in rat cerebral arteries

DEFF Research Database (Denmark)

Sandhu, Hardip; Ansar, Saema; Edvinsson, Lars

2010-01-01

on translational level and increased respective contractions. The prostanoid TP receptor mediated contraction curve was left-wards shifted by organ culture. Organ culture was associated with elevated pERK1/2 in the vascular smooth muscle cells: the MEK1/2 inhibitor U0126 attenuated the endothelin ET(B) receptor...... mediated contraction at post-translational level or by changing the receptor affinities. The serotonin 5-HT(1B) receptor and prostanoid TP receptor mediated contractions were abolished by U0126. Administration of U0126 6h after start of incubation blocked the receptor upregulation. In conclusion, MEK...

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

International Nuclear Information System (INIS)

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

2014-01-01

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

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

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

2014-10-01

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

Modeling Cerebrovascular Pathophysiology in Amyloid-β Metabolism using Neural-Crest-Derived Smooth Muscle Cells

Directory of Open Access Journals (Sweden)

Christine Cheung

2014-10-01

Full Text Available Summary: There is growing recognition of cerebrovascular contributions to neurodegenerative diseases. In the walls of cerebral arteries, amyloid-beta (Aβ accumulation is evident in a majority of aged people and patients with cerebral amyloid angiopathy. Here, we leverage human pluripotent stem cells to generate vascular smooth muscle cells (SMCs from neural crest progenitors, recapitulating brain-vasculature-specific attributes of Aβ metabolism. We confirm that the lipoprotein receptor, LRP1, functions in our neural-crest-derived SMCs to mediate Aβ uptake and intracellular lysosomal degradation. Hypoxia significantly compromises the contribution of SMCs to Aβ clearance by suppressing LRP1 expression. This enabled us to develop an assay of Aβ uptake by using the neural crest-derived SMCs with hypoxia as a stress paradigm. We then tested several vascular protective compounds in a high-throughput format, demonstrating the value of stem-cell-based phenotypic screening for novel therapeutics and drug repurposing, aimed at alleviating amyloid burden. : The contribution of blood vessel pathologies to neurodegenerative disorders is relatively neglected, partly due to inadequate human tissues for research. By using human stem cells, Cheung et al. establish a method of generating vascular smooth muscle cells (SMCs from neural crest progenitors, the primary precursors that give rise to brain blood vessels. These stem-cell-derived SMCs display defective amyloid processing under chronic hypoxia, a phenomenon well documented in the cerebral vasculatures of aged people and patients with Alzheimer’s disease.

MicroRNA expression profile and functional analysis reveal their roles in contact inhibition and its disruption switch of rat vascular smooth muscle cells.

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Sun, Ye-Ying; Qin, Shan-Shan; Cheng, Yun-Hui; Wang, Chao-Yun; Liu, Xiao-Jun; Liu, Ying; Zhang, Xiu-Li; Zhang, Wendy; Zhan, Jia-Xin; Shao, Shuai; Bian, Wei-Hua; Luo, Bi-Hui; Lu, Dong-Feng; Yang, Jian; Wang, Chun-Hua; Zhang, Chun-Xiang

2018-05-01

Contact inhibition and its disruption of vascular smooth muscle cells (VSMCs) are important cellular events in vascular diseases. But the underlying molecular mechanisms are unclear. In this study we investigated the roles of microRNAs (miRNAs) in the contact inhibition and its disruption of VSMCs and the molecular mechanisms involved. Rat VSMCs were seeded at 30% or 90% confluence. MiRNA expression profiles in contact-inhibited confluent VSMCs (90% confluence) and non-contact-inhibited low-density VSMCs (30% confluence) were determined. We found that multiple miRNAs were differentially expressed between the two groups. Among them, miR-145 was significantly increased in contact-inhibited VSMCs. Serum could disrupt the contact inhibition as shown by the elicited proliferation of confluent VSMCs. The contact inhibition disruption accompanied with a down-regulation of miR-145. Serum-induced contact inhibition disruption of VSMCs was blocked by overexpression of miR-145. Moreover, downregulation of miR-145 was sufficient to disrupt the contact inhibition of VSMCs. The downregulation of miR-145 in serum-induced contact inhibition disruption was related to the activation PI3-kinase/Akt pathway, which was blocked by the PI3-kinase inhibitor LY294002. KLF5, a target gene of miR-145, was identified to be involved in miR-145-mediated effect on VSMC contact inhibition disruption, as it could be inhibited by knockdown of KLF5. In summary, our results show that multiple miRNAs are differentially expressed in contact-inhibited VSMCs and in non-contact-inhibited VSMCs. Among them, miR-145 is a critical gene in contact inhibition and its disruption of VSMCs. PI3-kinase/Akt/miR-145/KLF5 is a critical signaling pathway in serum-induced contact inhibition disruption. Targeting of miRNAs related to the contact inhibition of VSMCs may represent a novel therapeutic approach for vascular diseases.

Buddleja officinalis suppresses high glucose-induced vascular smooth muscle cell proliferation: role of mitogen-activated protein kinases, nuclear factor-kappaB and matrix metalloproteinases.

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

2010-02-01

Diabetes mellitus is a well-established risk factor for vascular diseases caused by atherosclerosis. In the development of diabetic atherogenesis, vascular smooth muscle cell proliferation is recognized as a key event. Thus, we aimed to investigate whether an ethanol extract of Buddleja officinalis (EBO) suppresses high glucose-induced proliferation in primary cultured human aortic smooth muscle cells (HASMC). [(3)H]-thymidine incorporation revealed that incubation of HASMC with a high concentration of glucose (25 mmol/L) increased cell proliferation. The expression levels of cell cycle protein were also increased by treatment with high glucose concentration. Pretreatment of HASMC with EBO significantly attenuated the increase of high glucose-induced cell proliferation as well as p38 mitogen-activated protein kinases (MAPK) and JNK phosphorylation. EBO suppressed high glucose-induced matrix metalloproteinase (MMP)-9 activity in a dose-dependent manner. In addition, EBO suppressed nuclear factor-kappaB (NF-kappaB) nuclear translocation and transcriptional activity in high glucose conditions. Taken together, the present data suggest that EBO could suppress high glucose-induced atherosclerotic processes through inhibition of p38, JNK, NF-kappaB and MMP signal pathways in HASMC.

Patent ductus arteriosus in mice with smooth muscle-specific Jag1 deletion

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Feng, Xuesong; Krebs, Luke T.; Gridley, Thomas

2010-01-01

The ductus arteriosus is an arterial vessel that shunts blood flow away from the lungs during fetal life, but normally occludes after birth to establish the adult circulation pattern. Failure of the ductus arteriosus to close after birth is termed patent ductus arteriosus and is one of the most common congenital heart defects. Mice with smooth muscle cell-specific deletion of Jag1, which encodes a Notch ligand, die postnatally from patent ductus arteriosus. These mice exhibit defects in contractile smooth muscle cell differentiation in the vascular wall of the ductus arteriosus and adjacent descending aorta. These defects arise through an inability to propagate the JAG1-Notch signal via lateral induction throughout the width of the vascular wall. Both heterotypic endothelial smooth muscle cell interactions and homotypic vascular smooth muscle cell interactions are required for normal patterning and differentiation of the ductus arteriosus and adjacent descending aorta. This new model for a common congenital heart defect provides novel insights into the genetic programs that underlie ductus arteriosus development and closure. PMID:21068062

The mechanism of inhibitory effect of γ-ray irradiation on rat vascular smooth muscle cells

International Nuclear Information System (INIS)

Zhuang Yongzhi; Wang Junjie; Zhang Zhanchun; Jia Tingzhen

2001-01-01

Objective: To investigate the inhibitory effect of γ-ray irradiation on rat vascular smooth muscle cells (VSMCs). Methods: Dose-survival curve of VSMCs was figured by colony formation. The effect of γ-ray irradiation on viability and proliferation of VSMCs was observed by 3 H incorporation. Flow cytometry and DNA Ladder were used to detect the apoptosis effect of γ-ray irradiation on VSMCs. Results: The values of D 0 , D q , D 37 and N for VSMCs were 1.95 Gy, 1.76 Gy, 3.71 Gy and 2.47, respectively. The inhibitory effect of γ-ray irradiation on VSMCs proliferation was dose-dependent, being stronger along with increase of dose. VSMCs did not undergo apoptosis within 48 hours after γ-ray irradiation. Conclusion: γ-ray irradiation could inhibit the proliferation of VSMCs, the main mechanism of which is the killing effect and inhibition of mitosis of VSMCs

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

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

2018-03-15

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

MicroRNA-125b Affects Vascular Smooth Muscle Cell Function by Targeting Serum Response Factor

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Zhibo Chen

2018-04-01

Full Text Available Background/Aims: Increasing evidence links microRNAs to the pathogenesis of peripheral vascular disease. We recently found microRNA-125b (miR-125b to be one of the most significantly down‑regulated microRNAs in human arteries with arteriosclerosis obliterans (ASO of the lower extremities. However, its function in the process of ASO remains unclear. This study aimed to investigate the expression, regulatory mechanisms, and functions of miR-125b in the process of ASO. Methods: Using the tissue explants adherent method, vascular smooth muscle cells (VSMCs were prepared for this study. A rat carotid artery balloon injury model was constructed to simulate the development of vascular neointima, and a lentiviral transduction system was used to overexpress serum response factor (SRF or miR-125b. Quantitative real‑time PCR (qRT‑PCR was used to detect the expression levels of miR‑125b and SRF mRNA. Western blotting was performed to determine the expression levels of SRF and Ki67. In situ hybridization analysis was used to analyze the location and expression levels of miR-125b. CCK-8 and EdU assays were used to assess cell proliferation, and transwell and wound closure assays were performed to measure cell migration. Flow cytometry was used to evaluate cell apoptosis, and a dual-luciferase reporter assay was conducted to examine the effects of miR‑125b on SRF. Immunohistochemistry and immunofluorescence analyses were performed to analyze the location and expression levels of SRF and Ki67. Results: miR-125b expression was decreased in ASO arteries and platelet-derived growth factor (PDGF-BB-stimulated VSMCs. miR-125b suppressed VSMC proliferation and migration but promoted VSMC apoptosis. SRF was determined to be a direct target of miR-125b. Exogenous miR-125b expression modulated SRF expression and inhibited vascular neointimal formation in balloon-injured rat carotid arteries. Conclusions: These findings demonstrate a specific role of the mi

Low-intensity interval exercise training attenuates coronary vascular dysfunction and preserves Ca2+-sensitive K+ current in miniature swine with LV hypertrophy

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Tharp, Darla L.; Ivey, Jan R.; Ganjam, Venkataseshu K.; Bowles, Douglas K.

2011-01-01

Coronary vascular dysfunction has been observed in several models of heart failure (HF). Recent evidence indicates that exercise training is beneficial for patients with HF, but the precise intensity and underlying mechanisms are unknown. Left ventricular (LV) hypertrophy can play a significant role in the development of HF; therefore, the purpose of this study was to assess the effects of low-intensity interval exercise training on coronary vascular function in sedentary (HF) and exercise trained (HF-TR) aortic-banded miniature swine displaying LV hypertrophy. Six months postsurgery, in vivo coronary vascular responses to endothelin-1 (ET-1) and adenosine were measured in the left anterior descending coronary artery. Baseline and maximal coronary vascular conductance were similar between all groups. ET-1-induced reductions in coronary vascular conductance (P < 0.05) were greater in HF vs. sedentary control and HF-TR groups. Pretreatment with the ET type A (ETA) receptor blocker BQ-123 prevented ET-1 hypersensitivity in HF animals. Whole cell voltage clamp was used to characterize composite K+ currents (IK+) in coronary smooth muscle cells. Raising internal Ca2+ from 200 to 500 nM increased Ca2+-sensitive K+ current in HF-TR and control, but not HF animals. In conclusion, an ETA-receptor-mediated hypersensitivity to ET-1, elevated resting LV wall tension, and decreased coronary smooth muscle cell Ca2+-sensitive IK+ was found in sedentary animals with LV hypertrophy. Low-intensity interval exercise training preserved normal coronary vascular function and smooth muscle cell Ca2+-sensitive IK+, illustrating a potential mechanism underlying coronary vascular dysfunction in a large-animal model of LV hypertrophy. Our results demonstrate the potential clinical impact of exercise on coronary vascular function in HF patients displaying pathological LV hypertrophy. PMID:21841018

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

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

2013-04-15

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

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

International Nuclear Information System (INIS)

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

2013-01-01

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

Characterization of the effect of penehyclidine hydrochloride on muscarinic receptor subtypes mediating the contraction of guinea-pig isolated gastrointestinal smooth muscle.

Science.gov (United States)

Xiao, Hong-Tao; Liao, Zhi; Meng, Xian-Min; Yan, Xiao-Yan; Chen, Shu-Jie; Mo, Zheng-Ji

2009-07-01

The aim was to characterize the effect of penehyclidine hydrochloride, which mediates the relaxation of guinea-pig isolated gastrointestinal smooth muscle, on muscarinic receptor subtypes. Radioimmune assay was used to determine cAMP levels in isolated guinea-pig gastrointestinal smooth muscle to compare the selective effects of penehyclidine hydrochloride on muscarinic receptor subtypes. The results indicated that the relaxing effect of penehyclidine hydrochloride on isolated gastrointestinal smooth muscle contraction induced by acetylcholine was stronger than that of atropine (based on PA2 values). In the radioimmune assay, penehyclidine hydrochloride increased the cAMP content in isolated guinea-pig stomach smooth muscle and decreased the cAMP content in isolated guinea-pig intestinal smooth muscle, but the difference was not statistically significant at a dose of 10 mumol/l. The results suggest that penehyclidine hydrochloride has little or no effect on M2 receptor subtypes in guinea-pig gastrointestinal smooth muscle.

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

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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

Synthetic smooth muscle in the outer blood plexus of the rhinarium skin of Lemur catta L.

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Elofsson, Rolf; Kröger, Ronald H H

2017-01-01

The skin of the lemur nose tip (rhinarium) has arterioles in the outer vascular plexus that are endowed with an unusual coat of smooth muscle cells. Comparison with the arterioles of the same area in a number of unrelated mammalians shows that the lemur pattern is unique. The vascular smooth muscle cells belong to the synthetic type. The function of synthetic smooth muscles around the terminal vessels in the lemur rhinarium is unclear but may have additional functions beyond regulation of vessel diameter.

Sodium pump activity and calcium relaxation in vascular smooth muscle of deoxycorticosterone acetate-salt rats

International Nuclear Information System (INIS)

Soltis, E.E.; Field, F.P.

1986-01-01

The Na + -K + pump activity was determined in femoral arterial smooth muscle from deoxycorticosterone acetate (DOCA)-salt hypertensive rats using potassium relaxation and ouabain-sensitive 86 Rb uptake as indices. The membrane-stabilizing effect of calcium and its relation to Na + -K + pump activity also were examined. Femoral arteries from DOCA-salt rats exhibited a greater relaxation in response to potassium addition after contraction with norepinephrine in a low potassium (0.6 mM) Krebs solution. The concentration of potassium required to produce a 50% relaxation was significantly less in DOCA-salt rats. Ouabain-sensitive 86 Rb uptake was significantly greater at 3, 10, and 20 minutes of 86 Rb incubation in femoral arteries from DOCA-salt rats. Linear regression analysis revealed a significant correlation between the uptake of 86 Rb and time of incubation in both control and DOCA-salt rats. A significant difference in the slopes of the regression lines showed that the rate of uptake was greater in DOCA-salt rats. No difference was observed in ouabain-insensitive 86 Rb uptake. A dose-dependent relaxation in response to increasing concentrations of calcium following contraction to norepinephrine was observed in femoral arteries from control and DOCA-salt rats. The relaxation was directly dependent on the level of extracellular potassium and was blocked by ouabain. Femoral arteries from DOCA-salt rats relaxed to a significantly greater extent in response to calcium at each level of potassium when compared with controls. These results provide further evidence for an increase in Na + -K + pump activity in vascular smooth muscle from DOCA-salt hypertensive rats

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

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Cersosimo, Eugenio; Xu, Xiaojing; Musi, Nicolas

2012-02-15

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

miR-125b targets DNMT3b and mediates p53 DNA methylation involving in the vascular smooth muscle cells proliferation induced by homocysteine

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Cao, ChengJian [Key Laboratory of Basic Research in Cardio-Cerebral Vascular Diseases, Ningxia Medical University, Yinchuan (China); Zhang, HuiPing [Department of Prenatal Diagnosis Center, General Hospital of Ningxia Medical University, Yinchuan (China); Zhao, Li [Department of Medical Laboratory, Ningxia Medical University, Yinchuan (China); Zhou, Longxia [Department of Basic Medicine, Ningxia Medical University, Yinchuan (China); Zhang, Minghao; Xu, Hua [Key Laboratory of Basic Research in Cardio-Cerebral Vascular Diseases, Ningxia Medical University, Yinchuan (China); Department of Basic Medicine, Ningxia Medical University, Yinchuan (China); Han, Xuebo [Department of Medical Laboratory, Ningxia Medical University, Yinchuan (China); Li, Guizhong; Yang, Xiaoling [Key Laboratory of Basic Research in Cardio-Cerebral Vascular Diseases, Ningxia Medical University, Yinchuan (China); Department of Basic Medicine, Ningxia Medical University, Yinchuan (China); Jiang, YiDeng, E-mail: jyjcyxy@yeah.net [Key Laboratory of Basic Research in Cardio-Cerebral Vascular Diseases, Ningxia Medical University, Yinchuan (China); Department of Basic Medicine, Ningxia Medical University, Yinchuan (China)

2016-09-10

MicroRNAs (miRNAs) are short non-coding RNA and play crucial roles in a wide array of biological processes, including cell proliferation, differentiation and apoptosis. Our previous studies found that homocysteine(Hcy) can stimulate the proliferation of vascular smooth muscle cells (VSMCs), however, the underlying mechanisms were not fully elucidated. Here, we found proliferation of VSMCs induced by Hcy was of correspondence to the miR-125b expression reduced both in vitro and in the ApoE knockout mice, the hypermethylation of p53, its decreased expression, and DNA (cytosine-5)-methyltransferase 3b (DNMT3b) up-regulated. And, we found DNMT3b is a target of miR-125b, which was verified by the Dual-Luciferase reporter assay and western blotting. Besides, the siRNA interference for DNMT3b significantly decreased the methylation level of p53, which unveiled the causative role of DNMT3b in p53 hypermethylation. miR-125b transfection further confirmed its regulative roles on p53 gene methylation status and the VSMCs proliferation. Our data suggested that a miR-125b-DNMT3b-p53 signal pathway may exist in the VSMCs proliferation induced by Hcy.

miR-125b targets DNMT3b and mediates p53 DNA methylation involving in the vascular smooth muscle cells proliferation induced by homocysteine

International Nuclear Information System (INIS)

Cao, ChengJian; Zhang, HuiPing; Zhao, Li; Zhou, Longxia; Zhang, Minghao; Xu, Hua; Han, Xuebo; Li, Guizhong; Yang, Xiaoling; Jiang, YiDeng

2016-01-01

MicroRNAs (miRNAs) are short non-coding RNA and play crucial roles in a wide array of biological processes, including cell proliferation, differentiation and apoptosis. Our previous studies found that homocysteine(Hcy) can stimulate the proliferation of vascular smooth muscle cells (VSMCs), however, the underlying mechanisms were not fully elucidated. Here, we found proliferation of VSMCs induced by Hcy was of correspondence to the miR-125b expression reduced both in vitro and in the ApoE knockout mice, the hypermethylation of p53, its decreased expression, and DNA (cytosine-5)-methyltransferase 3b (DNMT3b) up-regulated. And, we found DNMT3b is a target of miR-125b, which was verified by the Dual-Luciferase reporter assay and western blotting. Besides, the siRNA interference for DNMT3b significantly decreased the methylation level of p53, which unveiled the causative role of DNMT3b in p53 hypermethylation. miR-125b transfection further confirmed its regulative roles on p53 gene methylation status and the VSMCs proliferation. Our data suggested that a miR-125b-DNMT3b-p53 signal pathway may exist in the VSMCs proliferation induced by Hcy.

Aspirin-induced AMP-activated protein kinase activation regulates the proliferation of vascular smooth muscle cells from spontaneously hypertensive rats

International Nuclear Information System (INIS)

Sung, Jin Young; Choi, Hyoung Chul

2011-01-01

Highlights: → Aspirin-induced AMPK phosphorylation was greater in VSMC from SHR than WKY. → Aspirin-induced AMPK phosphorylation inhibited proliferation of VSMC from SHR. → Low basal AMPK phosphorylation in SHR elicits increased VSMC proliferation. → Inhibition of AMPK restored decreased VSMC proliferation by aspirin in SHR. → Aspirin exerts anti-proliferative effect through AMPK activation in VSMC from SHR. -- Abstract: Acetylsalicylic acid (aspirin), used to reduce risk of cardiovascular disease, plays an important role in the regulation of cellular proliferation. However, mechanisms responsible for aspirin-induced growth inhibition are not fully understood. Here, we investigated whether aspirin may exert therapeutic effects via AMP-activated protein kinase (AMPK) activation in vascular smooth muscle cells (VSMC) from wistar kyoto rats (WKY) and spontaneously hypertensive rats (SHR). Aspirin increased AMPK and acetyl-CoA carboxylase phosphorylation in a time- and dose-dependent manner in VSMCs from WKY and SHR, but with greater efficacy in SHR. In SHR, a low basal phosphorylation status of AMPK resulted in increased VSMC proliferation and aspirin-induced AMPK phosphorylation inhibited proliferation of VSMCs. Compound C, an AMPK inhibitor, and AMPK siRNA reduced the aspirin-mediated inhibition of VSMC proliferation, this effect was more pronounced in SHR than in WKY. In VSMCs from SHR, aspirin increased p53 and p21 expression and inhibited the expression of cell cycle associated proteins, such as p-Rb, cyclin D, and cyclin E. These results indicate that in SHR VSMCs aspirin exerts anti-proliferative effects through the induction of AMPK phosphorylation.

Aspirin-induced AMP-activated protein kinase activation regulates the proliferation of vascular smooth muscle cells from spontaneously hypertensive rats

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Sung, Jin Young [Department of Pharmacology, College of Medicine, Yeungnam University, Daegu 705-717 (Korea, Republic of); Choi, Hyoung Chul, E-mail: hcchoi@med.yu.ac.kr [Department of Pharmacology, College of Medicine, Yeungnam University, Daegu 705-717 (Korea, Republic of)

2011-05-06

Highlights: {yields} Aspirin-induced AMPK phosphorylation was greater in VSMC from SHR than WKY. {yields} Aspirin-induced AMPK phosphorylation inhibited proliferation of VSMC from SHR. {yields} Low basal AMPK phosphorylation in SHR elicits increased VSMC proliferation. {yields} Inhibition of AMPK restored decreased VSMC proliferation by aspirin in SHR. {yields} Aspirin exerts anti-proliferative effect through AMPK activation in VSMC from SHR. -- Abstract: Acetylsalicylic acid (aspirin), used to reduce risk of cardiovascular disease, plays an important role in the regulation of cellular proliferation. However, mechanisms responsible for aspirin-induced growth inhibition are not fully understood. Here, we investigated whether aspirin may exert therapeutic effects via AMP-activated protein kinase (AMPK) activation in vascular smooth muscle cells (VSMC) from wistar kyoto rats (WKY) and spontaneously hypertensive rats (SHR). Aspirin increased AMPK and acetyl-CoA carboxylase phosphorylation in a time- and dose-dependent manner in VSMCs from WKY and SHR, but with greater efficacy in SHR. In SHR, a low basal phosphorylation status of AMPK resulted in increased VSMC proliferation and aspirin-induced AMPK phosphorylation inhibited proliferation of VSMCs. Compound C, an AMPK inhibitor, and AMPK siRNA reduced the aspirin-mediated inhibition of VSMC proliferation, this effect was more pronounced in SHR than in WKY. In VSMCs from SHR, aspirin increased p53 and p21 expression and inhibited the expression of cell cycle associated proteins, such as p-Rb, cyclin D, and cyclin E. These results indicate that in SHR VSMCs aspirin exerts anti-proliferative effects through the induction of AMPK phosphorylation.

Overexpression of Catalase in Vascular Smooth Muscle Cells Prevents the Formation of Abdominal Aortic Aneurysms

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Parastatidis, Ioannis; Weiss, Daiana; Joseph, Giji; Taylor, W Robert

2013-01-01

Objective Elevated levels of oxidative stress have been reported in abdominal aortic aneurysms (AAA), but which reactive oxygen species (ROS) promotes the development of AAA remains unclear. Here we investigate the effect of the hydrogen peroxide (H2O2) degrading enzyme catalase on the formation of AAA. Approach and Results AAA were induced with the application of calcium chloride (CaCl2) on mouse infrarenal aortas. The administration of PEG-catalase, but not saline, attenuated the loss of tunica media and protected against AAA formation (0.91±0.1 mm vs. 0.76±0.09 mm). Similarly, in a transgenic mouse model, catalase over-expression in the vascular smooth muscle cells (VSMC) preserved the thickness of tunica media and inhibited aortic dilatation by 50% (0.85±0.14 mm vs. 0.57±0.08 mm). Further studies showed that injury with CaCl2 decreased catalase expression and activity in the aortic wall. Pharmacologic administration or genetic over-expression of catalase restored catalase activity and subsequently decreased matrix metalloproteinase activity. In addition, a profound reduction in inflammatory markers and VSMC apoptosis was evident in aortas of catalase over-expressing mice. Interestingly, as opposed to infusion of PEG-catalase, chronic over-expression of catalase in VSMC did not alter the total aortic H2O2 levels. Conclusions The data suggest that a reduction in aortic wall catalase activity can predispose to AAA formation. Restoration of catalase activity in the vascular wall enhances aortic VSMC survival and prevents AAA formation primarily through modulation of matrix metalloproteinase activity. PMID:23950141

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

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Joey Z. Liu

2009-01-01

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

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

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

2001-01-01

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

Cyclic GMP alters Ca exchange in vascular smooth muscle

International Nuclear Information System (INIS)

Magliola, L.; Bailey, B.; Jones, A.W.

1986-01-01

Contraction and 42 K efflux from vascular smooth muscle stimulated either by norepinephrine (NE) or by K-depolarization is dependent on an increase in cytosolic Ca concentration. The purpose of this study was to determine if cyclic GMP (cGMP) inhibited these processes and if inhibition was secondary to the action of cGMP on Ca movements. Basal cGMP content of rat aorta was 1.2 fmol/mg wet wt. Sodium nitroprusside (NP) increased cGMP ∼2-fold at 1 nM and ∼750-fold at 1 μM with no effect on cAMP levels. A 5 min pretreatment with NP (1 μM) completely prevented tension development induced by 3 μM NE. The same concentration of NP also inhibited NE-stimulated 42 K and 45 Ca efflux > 90 and > 80%, respectively. Removal of NP in the continued presence of NE (3 μM) caused recovery of the 42 K efflux response to ∼75% of control with a half-time of ∼2.5 min. NP (1 μM) also caused a rapid relaxation of aorta contracted with 3 μM NE and a loss of the 42 K efflux response with half-times of 2-3 min. In contrast, 100 μM NP produced only a 50% inhibition of contraction induced by high K (55 mM). Also, NP (1 μM) inhibited K-stimulated 42 K efflux only ∼25%. These results demonstrate both a concentration- and a time-dependent relationship between increases in cGMP induced by NP and decreases in NE-stimulated contraction, 42 K and 45 Ca effluxes. They also indicate that the sensitivity of NE-induced contraction and 42 K efflux to NP is greater than that induced by high K. These studies suggest that cGMP modulates the control sites for Ca exchange in the plasma membrane and sarcoplasmic reticulum

Low-intensity interval exercise training attenuates coronary vascular dysfunction and preserves Ca²⁺-sensitive K⁺ current in miniature swine with LV hypertrophy.

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Emter, Craig A; Tharp, Darla L; Ivey, Jan R; Ganjam, Venkataseshu K; Bowles, Douglas K

2011-10-01

Coronary vascular dysfunction has been observed in several models of heart failure (HF). Recent evidence indicates that exercise training is beneficial for patients with HF, but the precise intensity and underlying mechanisms are unknown. Left ventricular (LV) hypertrophy can play a significant role in the development of HF; therefore, the purpose of this study was to assess the effects of low-intensity interval exercise training on coronary vascular function in sedentary (HF) and exercise trained (HF-TR) aortic-banded miniature swine displaying LV hypertrophy. Six months postsurgery, in vivo coronary vascular responses to endothelin-1 (ET-1) and adenosine were measured in the left anterior descending coronary artery. Baseline and maximal coronary vascular conductance were similar between all groups. ET-1-induced reductions in coronary vascular conductance (P < 0.05) were greater in HF vs. sedentary control and HF-TR groups. Pretreatment with the ET type A (ET(A)) receptor blocker BQ-123 prevented ET-1 hypersensitivity in HF animals. Whole cell voltage clamp was used to characterize composite K(+) currents (I(K(+))) in coronary smooth muscle cells. Raising internal Ca(2+) from 200 to 500 nM increased Ca(2+)-sensitive K(+) current in HF-TR and control, but not HF animals. In conclusion, an ET(A)-receptor-mediated hypersensitivity to ET-1, elevated resting LV wall tension, and decreased coronary smooth muscle cell Ca(2+)-sensitive I(K(+)) was found in sedentary animals with LV hypertrophy. Low-intensity interval exercise training preserved normal coronary vascular function and smooth muscle cell Ca(2+)-sensitive I(K(+)), illustrating a potential mechanism underlying coronary vascular dysfunction in a large-animal model of LV hypertrophy. Our results demonstrate the potential clinical impact of exercise on coronary vascular function in HF patients displaying pathological LV hypertrophy.

A new iridoid and effect on the rat aortic vascular smooth muscle cell proliferation of isolated compounds from Buddleja officinalis.

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Tai, Bui Huu; Nhiem, Nguyen Xuan; Quang, Tran Hong; Ngan, Nguyen Thi Thanh; Tung, Nguyen Huu; Kim, Yohan; Lee, Jung-Jin; Myung, Chang-Seon; Cuong, Nguyen Manh; Kim, Young Ho

2011-06-01

A new iridoid, named methylscutelloside (1) together with 19 known compounds belonging to the iridoids (2-4), monoterpenoids (5), flavonoids (6-8), triterpenoids (9-14), and phenylethanoids (15-20) were isolated from the flowers of Buddleja officinalis. Their chemical structures were elucidated on the basis of physicochemical properties, and by spectroscopic methods including 1D, 2D NMR, and MS. All isolated compounds were tested in vitro for their effects on the proliferation of rat aortic vascular smooth muscle cells (VSMCs). Among them, iridoids were the main active components and showed significant inhibitory effects on PDGF-BB-induced proliferation in rat aortic VSMCs. Copyright © 2011 Elsevier Ltd. All rights reserved.

Intracellular Na+ regulation of Na+ pump sites in cultured vascular smooth muscle cells

International Nuclear Information System (INIS)

Allen, J.C.; Navran, S.S.; Seidel, C.L.; Dennison, D.K.; Amann, J.M.; Jemelka, S.K.

1989-01-01

Enzymatically dispersed cells from canine saphenous vein and femoral artery were grown in fetal calf serum and studied at day 0 (freshly dispersed) through confluence in primary culture. Intracellular Na levels (Nai), but not intracellular K (Ki), were increased after 24 h in culture and then decreased to a steady state by 4 days. Na+ pump site number [( 3 H] ouabain binding) increased through day 3 and remained elevated. Nai was still elevated at 2 days when the Na+ pump site number began to increase. Total pump turnover (maximum ouabain-inhibited 86 Rb uptake) reflected the increase in Na+ pump site number. These key events precede the observed increases in both protein production and cellular proliferation. If the same cells are maintained in defined medium, without fetal calf serum, Nai, Ki, and the number of [ 3 H]ouabain binding sites do not change with time. These data are consistent with the suggestion that the initial mitogenic response of vascular smooth muscle cells to fetal calf serum involves an increased Na+ influx, and a Nai accumulation, caused by low Na+ pump density. The synthesis of new pump sites effects a decrease in the accumulated Nai, which may be related to cell proliferation

Transcriptional Control of Vascular Smooth Muscle Cell Proliferation by Peroxisome Proliferator-Activated Receptor-γ: Therapeutic Implications for Cardiovascular Diseases

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Florence Gizard

2008-01-01

Full Text Available Proliferation of vascular smooth muscle cells (SMCs is a critical process for the development of atherosclerosis and complications of procedures used to treat atherosclerotic diseases, including postangioplasty restenosis, vein graft failure, and transplant vasculopathy. Peroxisome proliferator-activated receptor (PPAR γ is a member of the nuclear hormone receptor superfamily and the molecular target for the thiazolidinediones (TZD, used clinically to treat insulin resistance in patients with type 2 diabetes. In addition to their efficacy to improve insulin sensitivity, TZD exert a broad spectrum of pleiotropic beneficial effects on vascular gene expression programs. In SMCs, PPARγ is prominently upregulated during neointima formation and suppresses the proliferative response to injury of the arterial wall. Among the molecular target genes regulated by PPARγ in SMCs are genes encoding proteins involved in the regulation of cell-cycle progression, cellular senescence, and apoptosis. This inhibition of SMC proliferation is likely to contribute to the prevention of atherosclerosis and postangioplasty restenosis observed in animal models and proof-of-concept clinical studies. This review will summarize the transcriptional target genes regulated by PPARγ in SMCs and outline the therapeutic implications of PPARγ activation for the treatment and prevention of atherosclerosis and its complications.

Retinoid-induced expression and activity of an immediate early tumor suppressor gene in vascular smooth muscle cells.

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Jeffrey W Streb

2011-04-01

Full Text Available Retinoids are used clinically to treat a number of hyper-proliferative disorders and have been shown in experimental animals to attenuate vascular occlusive diseases, presumably through nuclear receptors bound to retinoic acid response elements (RARE located in target genes. Here, we show that natural or synthetic retinoids rapidly induce mRNA and protein expression of a specific isoform of A-Kinase Anchoring Protein 12 (AKAP12β in cultured smooth muscle cells (SMC as well as the intact vessel wall. Expression kinetics and actinomycin D studies indicate Akap12β is a retinoid-induced, immediate-early gene. Akap12β promoter analyses reveal a conserved RARE mildly induced with atRA in a region that exhibits hyper-acetylation. Immunofluorescence microscopy and protein kinase A (PKA regulatory subunit overlay assays in SMC suggest a physical association between AKAP12β and PKA following retinoid treatment. Consistent with its designation as a tumor suppressor, inducible expression of AKAP12β attenuates SMC growth in vitro. Further, immunohistochemistry studies establish marked decreases in AKAP12 expression in experimentally-injured vessels of mice as well as atheromatous lesions in humans. Collectively, these results demonstrate a novel role for retinoids in the induction of an AKAP tumor suppressor that blocks vascular SMC growth thus providing new molecular insight into how retiniods may exert their anti-proliferative effects in the injured vessel wall.

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

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

2014-11-01

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

Bone Morphogenetic Protein-Induced Msx1 and Msx2 Inhibit Myocardin-Dependent Smooth Muscle Gene Transcription▿

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Hayashi, Ken'ichiro; Nakamura, Seiji; Nishida, Wataru; Sobue, Kenji

2006-01-01

During the onset and progression of atherosclerosis, the vascular smooth muscle cell (VSMC) phenotype changes from differentiated to dedifferentiated, and in some cases, this change is accompanied by osteogenic transition, resulting in vascular calcification. One characteristic of dedifferentiated VSMCs is the down-regulation of smooth muscle cell (SMC) marker gene expression. Bone morphogenetic proteins (BMPs), which are involved in the induction of osteogenic gene ex...

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

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Lin Sheng

2012-06-01

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

Injuries to the vascular endothelium: vascular wall and endothelial dysfunction.

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Fisher, Mark

2008-01-01

Vascular endothelial injury has multiple elements, and this article focuses on ischemia-related processes that have particular relevance to ischemic stroke. Distinctions between necrotic and apoptotic cell death provide a basic science context in which to better understand the significance of classical core and penumbra concepts of acute stroke, with apoptotic processes particularly prominent in the penumbra. The mitochondria are understood to serve as a reservoir of proteins that mediate apoptosis. Oxidative stress pathways generating reactive oxygen species (ROS) are prominent in endothelial injury, both ischemic and nonischemic, with prominent roles of enzyme- and nonenzymemediated pathways; mitochondria once again have a critical role, particularly in the nonenzymatic pathways generating ROS. Inflammation also contributes to vascular endothelial injury, and endothelial cells have the capacity to rapidly increase expression of inflammatory mediators following ischemic challenge; this leads to enhanced leukocyte-endothelial interactions mediated by selectins and adhesion molecules. Preconditioning consists of a minor version of an injurious event, which in turn may protect vascular endothelium from injury following a more substantial event. Presence of the blood-brain barrier creates unique responses to endothelial injury, with permeability changes due to impairment of endothelial-matrix interactions compounding altered vasomotor tone and tissue perfusion mediated by nitric oxide. Pharmacological protection against vascular endothelial injury can be provided by several of the phosphodiesterases (cilostazol and dipyridamole), along with statins. Optimal clinical responses for protection of brain vascular endothelium may use preconditioning as a model, and will likely require combined protection against apoptosis, ROS, and inflammation.

Rapid effects of phytoestrogens on human colonic smooth muscle are mediated by oestrogen receptor beta.

LENUS (Irish Health Repository)

Hogan, A M

2012-02-01

Epidemiological studies have correlated consumption of dietary phytoestrogens with beneficial effects on colon, breast and prostate cancers. Genomic and non-genomic mechanisms are responsible for anti-carcinogenic effects but, until now, the effect on human colon was assumed to be passive and remote. No direct effect on human colonic smooth muscle has previously been described. Institutional research board approval was granted. Histologically normal colon was obtained from the proximal resection margin of colorectal carcinoma specimens. Circular smooth muscle strips were microdissected and suspended under 1g of tension in organ baths containing oxygenated Krebs solution at 37 degrees C. After an equilibration period, tissues were exposed to diarylpropionitrile (DPN) (ER beta agonist) and 1,3,5-tris(4-hydroxyphenyl)-4-propyl-1H-pyrazole (PPT) (ER alpha agonist) or to the synthetic phytoestrogen compounds genistein (n=8), daidzein (n=8), fisetin (n=8) and quercetin (n=8) in the presence or absence of fulvestrant (oestrogen receptor antagonist). Mechanism of action was investigated by inhibition of downstream pathways. The cholinergic agonist carbachol was used to induce contractile activity. Tension was recorded isometrically. Phytoestrogens inhibit carbachol-induced colonic contractility. In keeping with a non-genomic, rapid onset direct action, the effect was within minutes, reversible and similar to previously described actions of 17 beta oestradiol. No effect was seen in the presence of fulvestrant indicating receptor modulation. While the DPN exerted inhibitory effects, PPT did not. The effect appears to be reliant on a p38\\/mitogen activated protein kinase mediated induction of nitric oxide production in colonic smooth muscle. The present data set provides the first description of a direct effect of genistein, daidzein, fisetin and quercetin on human colonic smooth muscle. The presence of ER in colonic smooth muscle has been functionally proven and the beta

MFAP4 Promotes Vascular Smooth Muscle Migration, Proliferation and Accelerates Neointima Formation

DEFF Research Database (Denmark)

Schlosser, Anders; Pilecki, Bartosz; Hemstra, Line E.

2016-01-01

in the vascular wall. The role of MFAP4 in vascular biology is unknown. We aimed to test the hypothesis that MFAP4 would enhance integrin-dependent VSMC activation. APPROACH AND RESULTS: We produced Mfap4-deficient (Mfap4(-/-)) mice and performed carotid artery ligation to explore the role of MFAP4 in vascular...... kinase and downstream kinases. In addition, we showed that MFAP4 promotes monocyte chemotaxis in integrin αVβ3-dependent manner. CONCLUSIONS: MFAP4 regulates integrin αVβ3-induced VSMC proliferation and migration, as well as monocyte chemotaxis, and accelerates neointimal hyperplasia after vascular...

α-Iso-Cubebene Inhibits PDGF-Induced Vascular Smooth Muscle Cell Proliferation by Suppressing Osteopontin Expression

Science.gov (United States)

Jang, Min A.; Lee, Seung Jin; Baek, Seung Eun; Park, So Youn; Choi, Young Whan; Kim, Chi Dae

2017-01-01

α-Iso-cubebene (ICB) is a dibenzocyclooctadiene lignin contained in Schisandra chinensis (SC), a well-known medicinal herb that ameliorates cardiovascular symptoms. Thus, we examined the effect of ICB on vascular smooth muscle cell (VSMC) proliferation, a key feature of diverse vascular diseases. When VSMCs primary cultured from rat thoracic aorta were stimulated with PDGF (1–10 ng/ml), cell proliferation and osteopontin (OPN) expression were concomitantly up-regulated, but these effects were attenuated when cells were treated with MPIIIB10, a neutralizing monoclonal antibody for OPN. In aortic tissues exposed to PDGF, sprouting VSMC numbers increased, which was attenuated in tissues from OPN-deficient mice. Furthermore, VSMC proliferation and OPN expression induced by PDGF were attenuated dose-dependently by ICB (10 or 30 μg/ml). Reporter assays conducted using OPN promoter-luciferase constructs showed that the promoter region 538–234 bp of the transcription start site was responsible for transcriptional activity enhancement by PDGF, which was significantly inhibited by ICB. Putative binding sites for AP-1 and C/EBPβ in the indicated promoter region were suggested by TF Search, and increased binding of AP-1 and C/EBPβ in PDGF-treated VSMCs was demonstrated using a ChIP assay. The increased bindings of AP-1 and C/EBPβ into OPN promoter were attenuated by ICB. Moreover, the PDGF-induced expression of OPN was markedly attenuated in VSMCs transfected with siRNA for AP-1 and C/EBPβ. These results indicate that ICB inhibit VSMC proliferation by inhibiting the AP-1 and C/EBPβ signaling pathways and thus downregulating OPN expression. PMID:28114367

Leptin promotes osteoblast differentiation and mineralization of primary cultures of vascular smooth muscle cells by inhibiting glycogen synthase kinase (GSK)-3{beta}

Energy Technology Data Exchange (ETDEWEB)

Zeadin, Melec G.; Butcher, Martin K.; Shaughnessy, Stephen G. [Department of Medicine, McMaster University, Hamilton, ON (Canada); Thrombosis and Atherosclerosis Research Institute, Hamilton, ON (Canada); Werstuck, Geoff H., E-mail: Geoff.Werstuck@taari.ca [Department of Medicine, McMaster University, Hamilton, ON (Canada); Thrombosis and Atherosclerosis Research Institute, Hamilton, ON (Canada)

2012-09-07

Highlights: Black-Right-Pointing-Pointer Leptin promotes osteoblast differentiation of primary smooth muscle cells. Black-Right-Pointing-Pointer Leptin regulates the expression of genes involved in osteoblast differentiation. Black-Right-Pointing-Pointer Constitutively active GSK-3{beta} attenuates leptin-induced osteoblast differentiation. Black-Right-Pointing-Pointer This suggests that leptin signals through GSK-3{beta} to promote osteoblast differentiation. -- Abstract: In this study, we begin to investigate the underlying mechanism of leptin-induced vascular calcification. We found that treatment of cultured bovine aortic smooth muscle cells (BASMCs) with leptin (0.5-4 {mu}g/ml) induced osteoblast differentiation in a dose-dependent manner. Furthermore, we found that leptin significantly increased the mRNA expression of osteopontin and bone sialoprotein, while down-regulating matrix gla protein (MGP) expression in BASMCs. Key factors implicated in osteoblast differentiation, including members of the Wnt signaling pathway, were examined. Exposure to leptin enhanced phosphorylation of GSK-3{beta} on serine-9 thereby inhibiting activity and promoting the nuclear accumulation of {beta}-catenin. Transfection of BASMCs with an adenovirus that expressed constitutively active GSK-3{beta} (Ad-GSK-3{beta} S9A) resulted in a >2-fold increase in GSK-3{beta} activity and a significant decrease in leptin-induced alkaline phosphatase (ALP) activity. In addition, qRT-PCR analysis showed that GSK-3{beta} activation resulted in a significant decrease in the expression of osteopontin and bone sialoprotein, but a marked increase in MGP mRNA expression. When taken together, our results suggest a mechanism by which leptin promotes osteoblast differentiation and vascular calcification in vivo.

Hydroxyapatite and Calcified Elastin Induce Osteoblast-like Differentiation in Rat Aortic Smooth Muscle Cells

Science.gov (United States)

Lei, Yang; Sinha, Aditi; Nosoudi, Nasim; Grover, Ankit; Vyavahare, Naren

2014-01-01

Vascular calcification can be categorized into two different types. Intimal calcification related to atherosclerosis and elastin-specific medial arterial calcification (MAC). Osteoblast-like differentiation of vascular smooth muscle cells (VSMCs) has been shown in both types; however, how this relates to initiation of vascular calcification is unclear. We hypothesize that the initial deposition of hydroxyapatite-like mineral in MAC occurs on degraded elastin first and that causes osteogenic transformation of VSMCs. To test this, rat aortic smooth muscle cells (RASMCs) were cultured on hydroxyapatite crystals and calcified aortic elastin. Using RT-PCR and specific protein assays, we demonstrate that RASMCs lose their smooth muscle lineage markers like alpha smooth muscle actin (SMA) and myosin heavy chain (MHC) and undergo chondrogenic/osteogenic transformation. This is indicated by an increase in the expression of typical chondrogenic proteins such as aggrecan, collagen type II alpha 1(Col2a1) and bone proteins such as runt-related transcription factor 2 (RUNX2), alkaline phosphatase (ALP) and osteocalcin (OCN). Furthermore, when calcified conditions are removed, cells return to their original phenotype. Our data supports the hypothesis that elastin degradation and calcification precedes VSMCs' osteoblast-like differentiation. PMID:24447384

TRPV1 channels in human skeletal muscle feed arteries: implications for vascular function.

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Ives, Stephen J; Park, Song Young; Kwon, Oh Sung; Gifford, Jayson R; Andtbacka, Robert H I; Hyngstrom, John R; Richardson, Russell S

2017-09-01

What is the central question of this study? We sought to determine whether human skeletal muscle feed arteries (SFMAs) express TRPV 1 channels and what role they play in modulating vascular function. What is the main finding and its importance? Human SMFAs do express functional TRPV 1 channels that modulate vascular function, specifically opposing α-adrenergic receptor-mediated vasocontraction and potentiating vasorelaxation, in an endothelium-dependent manner, as evidenced by the α 1 -receptor-mediated responses. Thus, the vasodilatory role of TRPV 1 channels, and their ligand capsaicin, could be a potential therapeutic target for improving vascular function. Additionally, given the 'sympatholytic' effect of TRPV 1 activation and known endogenous activators (anandamide, reactive oxygen species, H + , etc.), TRPV 1 channels might contribute to functional sympatholysis during exercise. To examine the role of the transient receptor potential vanilloid type 1 (TRPV 1 ) ion channel in the vascular function of human skeletal muscle feed arteries (SMFAs) and whether activation of this heat-sensitive receptor could be involved in modulating vascular function, SMFAs from 16 humans (63 ± 5 years old, range 41-89 years) were studied using wire myography with capsaicin (TRPV 1 agonist) and without (control). Specifically, phenylephrine (α 1 -adrenergic receptor agonist), dexmedetomidine (α 2 -adrenergic receptor agonist), ACh and sodium nitroprusside concentration-response curves were established to assess the role of TRPV 1 channels in α-receptor-mediated vasocontraction as well as endothelium-dependent and -independent vasorelaxation, respectively. Compared with control conditions, capsaicin significantly attenuated maximal vasocontraction in response to phenylephrine [control, 52 ± 8% length-tension max (LT max ) and capsaicin, 21 ± 5%LT max ] and dexmedetomidine (control, 29 ± 12%LT max and capsaicin, 2 ± 3%LT max ), while robustly enhancing maximal

The role of inflammation in vascular insulin resistance with focus on IL-6

DEFF Research Database (Denmark)

Andersen, Kirsten; Pedersen, B.K.

2008-01-01

The present review focuses on the possible role of interleukin-(IL)-6 in vascular insulin resistance. The endothelium plays an important role in regulating the tone of the vasculature by releasing nitric oxide (NO) to the smooth muscles of the vessels, thereby regulating the distribution of blood....... It is likely that chronic low-level inflammation plays an important role in developing endothelial dysfunction mainly through proinflammatory actions of tumor necrosis factor alpha (TNF-alpha). TNF-alpha induces production of IL-6 and it has been suggested that a causal relationship exists between endothelial...... dysfunction and these cytokines. With regard to vascular insulin resistance, the available data point to a direct pathogenic role of TNF-alpha in mediating endothelial dysfunction, whereas with regard to IL-6 evidence is sparse and does not allow any firm conclusions Udgivelsesdato: 2008/9...

Opportunities to Target Specific Contractile Abnormalities with Smooth Muscle Protein Kinase Inhibitors

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Annegret Ulke-Lemée

2010-05-01

Full Text Available Smooth muscle is a major component of most hollow organ systems (e.g., airways, vasculature, bladder and gut/gastrointestine; therefore, the coordinated regulation of contraction is a key property of smooth muscle. When smooth muscle functions normally, it contributes to general health and wellness, but its dysfunction is associated with morbidity and mortality. Rho-associated protein kinase (ROCK is central to calcium-independent, actomyosin-mediated contractile force generation in the vasculature, thereby playing a role in smooth muscle contraction, cell motility and adhesion. Recent evidence supports an important role for ROCK in the increased vasoconstriction and remodeling observed in various models of hypertension. This review will provide a commentary on the development of specific ROCK inhibitors and their clinical application. Fasudil will be discussed as an example of bench-to-bedside development of a clinical therapeutic that is used to treat conditions of vascular hypercontractility. Due to the wide spectrum of biological processes regulated by ROCK, many additional clinical indications might also benefit from ROCK inhibition. Apart from the importance of ROCK in smooth muscle contraction, a variety of other protein kinases are known to play similar roles in regulating contractile force. The zipper-interacting protein kinase (ZIPK and integrin-linked kinase (ILK are two well-described regulators of contraction. The relative contribution of each kinase to contraction depends on the muscle bed as well as hormonal and neuronal stimulation. Unfortunately, specific inhibitors for ZIPK and ILK are still in the development phase, but the success of fasudil suggests that inhibitors for these other kinases may also have valuable clinical applications. Notably, the directed inhibition of ZIPK with a pseudosubstrate molecule shows unexpected effects on the contractility of gastrointestinal smooth muscle.

Preliminary investigations on the effects of a Strongylus vulgaris larval extract, mononuclear factors and platelet factors on equine smooth muscle cells in vitro.

Science.gov (United States)

Morgan, S J; Storts, R W; Stromberg, P C; Sowa, B A; Lay, J C

1989-01-01

Factors involved in the proliferation of equine vascular smooth muscle cells were studied in vitro. The most prominent proliferative responses in cultured vascular smooth muscle cells were induced by Strongylus vulgaris larval antigen extract (LAE) and platelet-derived factors. Less significant proliferative responses were obtained with conditioned media from S. vulgaris LAE stimulated and from unstimulated equine mononuclear leukocytes. Additionally, vascular smooth muscle cells exposed to S. vulgaris LAE developed numerous perinuclear vacuoles and were more spindle-shaped than control or smooth muscle cells exposed to other factors. Equine mononuclear leukocytes exposed to LAE developed prominent morphological changes, including enlargement, clumping and increased numbers of mitotic figures.

Molecular basis for interaction of Na⁺/K⁺-ATPase with other transporters in membrane microdomains of vascular smooth muscle cells

DEFF Research Database (Denmark)

Hansen, Anne Kirstine; Matchkov, Vladimir; Bouzinova, Elena

2008-01-01

Ouabain, a specific inhibitor of the Na+/K+-pump, has previously been shown to interfere with intercellular communication. We have recently demonstrated a mechanism of this action of ouabain (1). We have showed that gap junctions between vascular smooth muscle cells (SMCs) are regulated through...... an interaction between the Na+/K+-pump and the Na+/Ca2+-exchanger leading to an increase in the intracellular calcium concentration in discrete areas near the plasma membrane. This regulation suggests a close association of the proteins in microdomains. We have also suggested that this Na...

α-Trinositol inhibits FGF-stimulated growth of smooth muscle and breast cancer cells

International Nuclear Information System (INIS)

Siren, Matti J.; Vainiomaeki, Maija; Vaeaenaenen, Kalervo; Haerkoenen, Pirkko

2004-01-01

α-Trinositol (D-myo-inositol-1,2,6-trisphosphate), an isomer of the intracellular messenger IP 3 , has been studied for its anti-inflammatory and other effects in animal experiments and in human. The mechanisms of action remain unknown. Several human pathologies are associated with uncontrolled production of fibroblast growth factors (FGFs). FGF-2 induces vascular smooth muscle cell proliferation, which contributes to restenosis after coronary balloon angioplasty. The expression of several FGFs is also increased in tumors. We studied the effects of the water- and lipid-soluble derivatives of α-trinositol on the FGF-2- and/or FGF-8-induced proliferation of human pulmonary artery smooth muscle cells (HPASMC) and S115 mouse breast cancer cells. α-Trinositol decreased the FGF-mediated proliferation of HPASMC and S115 cells. Membrane permeability did not seem obligatory since the lipid-soluble form of α-trinositol was less effective than the water-soluble derivative. These results suggest a new biological function for certain phosphoinositides in the modulation of FGF-regulated processes

Effects of High Glucose on Vascular Endothelial Growth Factor Synthesis and Secretion in Aortic Vascular Smooth Muscle Cells from Obese and Lean Zucker Rats

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Mariella Trovati

2012-07-01

Full Text Available Type 1 diabetes is characterized by insulin deficiency, type 2 by both insulin deficiency and insulin resistance: in both conditions, hyperglycaemia is accompanied by an increased cardiovascular risk, due to increased atherosclerotic plaque formation/instabilization and impaired collateral vessel formation. An important factor in these phenomena is the Vascular Endothelial Growth Factor (VEGF, a molecule produced also by Vascular Smooth Muscle Cells (VSMC. We aimed at evaluating the role of high glucose on VEGF-A₁₆₄ synthesis and secretion in VSMC from lean insulin-sensitive and obese insulin-resistant Zucker rats (LZR and OZR. In cultured aortic VSMC from LZR and OZR incubated for 24 h with D-glucose (5.5, 15 and 25 mM or with the osmotic controls L-glucose and mannitol, we measured VEGF-A₁₆₄ synthesis (western, blotting and secretion (western blotting and ELISA. We observed that: (i D-glucose dose-dependently increases VEGF-A₁₆₄ synthesis and secretion in VSMC from LZR and OZR (n = 6, ANOVA p = 0.002–0.0001; (ii all the effects of 15 and 25 mM D-glucose are attenuated in VSMC from OZR vs. LZR (p = 0.0001; (iii L-glucose and mannitol reproduce the VEGF-A₁₆₄ modulation induced by D-glucose in VSMC from both LZR and OZR. Thus, glucose increases via an osmotic mechanism VEGF synthesis and secretion in VSMC, an effect attenuated in the presence of insulin resistance.

Activation of vascular cholinergic and adrenergic receptors induced by gamma rays

International Nuclear Information System (INIS)

Alya, G.

1999-10-01

Activation of vascular cholinergic receptors and adrenoceptors plays an important role in vasomotoricity and peripheric vascular resistance. These factors are essential in maintaining a stable blood pressure. The aim of this study is to investigate the radiosensitivity differences between vascular cholinergic receptors and adrenoceptors, and consequently to determinate the effects of ionizing radiation (whole body irradiation) on contractile response regulation of vascular smooth muscle fibers VSMF isolated from rat portal vein. Our results show that Clonidine, (non-specific adrenergic agonist), and phenylephrine which is more specific α1-adrenoceptor agonist, increase the VSMF contractions. The maximum effect is obtained at 10 -5 - 3.10 -5 M. On irradiated rats (1-3-5 Gy), there is an important shift thus, the maximal response (E m ax) can be obtained in lower concentrations of clonidine and phenylephrine. Irradiation deceases the contractile responses of VSMF mediated by cholinergic stimulation, in a dose dependant manner. With E m ax 1 Gy>E m ax 3 Gy>E m ax 5 Gy. Irradiated muscular fibers became less sensitive to acetylcholine, thus 3.10 -8 M. A. ch induced more than 50% of contraction force increase in normal conditions. This concentration induce generally a negligible effect after irradiation. The results reveal the existence of radiosensitivity differences between vascular cholinergic and adrenergic receptors. (author)

Activation of Transient Receptor Potential Melastatin Subtype 8 Attenuates Cold-Induced Hypertension Through Ameliorating Vascular Mitochondrial Dysfunction.

Science.gov (United States)

Xiong, Shiqiang; Wang, Bin; Lin, Shaoyang; Zhang, Hexuan; Li, Yingsha; Wei, Xing; Cui, Yuanting; Wei, Xiao; Lu, Zongshi; Gao, Peng; Li, Li; Zhao, Zhigang; Liu, Daoyan; Zhu, Zhiming

2017-08-02

Environmental cold-induced hypertension is common, but how to treat cold-induced hypertension remains an obstacle. Transient receptor potential melastatin subtype 8 (TRPM8) is a mild cold-sensing nonselective cation channel that is activated by menthol. Little is known about the effect of TRPM8 activation by menthol on mitochondrial Ca 2+ homeostasis and the vascular function in cold-induced hypertension. Primary vascular smooth muscle cells from wild-type or Trpm8 -/- mice were cultured. In vitro, we confirmed that sarcoplasmic reticulum-resident TRPM8 participated in the regulation of cellular and mitochondrial Ca 2+ homeostasis in the vascular smooth muscle cells. TRPM8 activation by menthol antagonized angiotensin II induced mitochondrial respiratory dysfunction and excess reactive oxygen species generation by preserving pyruvate dehydrogenase activity, which hindered reactive oxygen species-triggered Ca 2+ influx and the activation of RhoA/Rho kinase pathway. In vivo, long-term noxious cold stimulation dramatically increased vasoconstriction and blood pressure. The activation of TRPM8 by dietary menthol inhibited vascular reactive oxygen species generation, vasoconstriction, and lowered blood pressure through attenuating excessive mitochondrial reactive oxygen species mediated the activation of RhoA/Rho kinase in a TRPM8-dependent manner. These effects of menthol were further validated in angiotensin II-induced hypertensive mice. Long-term dietary menthol treatment targeting and preserving mitochondrial function may represent a nonpharmaceutical measure for environmental noxious cold-induced hypertension. © 2017 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.

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

Science.gov (United States)

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

1995-08-01

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

Establishment of artery smooth muscle cell proliferation model after subarachnoid hemorrhage in rats

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Yu-jie CHEN

2011-12-01

Full Text Available Objective The current paper aims to simulate the effects of hemolytic products on intracranial vascular smooth muscle cell after subarachnoid hemorrhage(SAH,and probe into the molecular mechanism and strategy for the prevention and cure of vascular proliferation after SAH.Methods Thirty Sprague-Dawley rats were randomly divided into three groups,including sham-operated,24 h after SAH,and 72 h after SAH groups.The artificial hemorrhage model around the common carotid artery was established for the latter two groups.The animals were put to death after 24 h and 72 h to take the common carotid artery,and to measure the expression level of PCNA,SM-α-actin protein,and mRNA in the smooth muscle cell.Results The PCNA mRNA expression was significantly up-regulated in the 24-h group(P < 0.01.The expression in the 72-h group was lower than that of the 24-h group(P < 0.01,whereas it was still remarkably higher than that of the sham group(P < 0.01.The SM-α-actin mRNA expression in the smooth muscle cell in the 24-h and 72-h groups decreased compared with that of the Sham group(P < 0.05,whereas the 72-h group was significantly lower than that of the 24-h group(P < 0.05.The protein expression of PCNA and SM-α-actin showed a similar trend.Conclusion The current experiment simulates better effects of the hemolytic products on vascular smooth muscle cell after SAH.It also shows that artificial hemorrhage around the common carotid artery could stimulate vascular smooth muscle cell to change from contractile phenotype into synthetic phenotype,and improve it to proliferate.

Progenitor cells in pulmonary vascular remodeling

Science.gov (United States)

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

2011-01-01

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

Essential Roles of Raf/Extracellular Signal-regulated Kinase/Mitogen-activated Protein Kinase Pathway, YY1, and Ca2+ Influx in Growth Arrest of Human Vascular Smooth Muscle Cells by Bilirubin*

Science.gov (United States)

Stoeckius, Marlon; Erat, Anna; Fujikawa, Tatsuya; Hiromura, Makoto; Koulova, Anna; Otterbein, Leo; Bianchi, Cesario; Tobiasch, Edda; Dagon, Yossi; Sellke, Frank W.; Usheva, Anny

2012-01-01

The biological effects of bilirubin, still poorly understood, are concentration-dependent ranging from cell protection to toxicity. Here we present data that at high nontoxic physiological concentrations, bilirubin inhibits growth of proliferating human coronary artery smooth muscle cells by three events. It impairs the activation of Raf/ERK/MAPK pathway and the cellular Raf and cyclin D1 content that results in retinoblastoma protein hypophosphorylation on amino acids S608 and S780. These events impede the release of YY1 to the nuclei and its availability to regulate the expression of genes and to support cellular proliferation. Moreover, altered calcium influx and calpain II protease activation leads to proteolytical degradation of transcription factor YY1. We conclude that in the serum-stimulated human vascular smooth muscle primary cell cultures, bilirubin favors growth arrest, and we propose that this activity is regulated by its interaction with the Raf/ERK/MAPK pathway, effect on cyclin D1 and Raf content, altered retinoblastoma protein profile of hypophosphorylation, calcium influx, and YY1 proteolysis. We propose that these activities together culminate in diminished 5 S and 45 S ribosomal RNA synthesis and cell growth arrest. The observations provide important mechanistic insight into the molecular mechanisms underlying the transition of human vascular smooth muscle cells from proliferative to contractile phenotype and the role of bilirubin in this transition. PMID:22262839

LRP1 in Brain Vascular Smooth Muscle Cells Mediates Local Clearance of Alzheimer's Amyloid-β

OpenAIRE

Kanekiyo, Takahisa; Liu, Chia-Chen; Shinohara, Mitsuru; Li, Jie; Bu, Guojun

2012-01-01

Impaired clearance of amyloid-β (Aβ) is a major pathogenic event for Alzheimer’s disease (AD). Aβ depositions in brain parenchyma as senile plaques and along cerebrovasculature as cerebral amyloid angiopathy (CAA) are hallmarks of AD. A major pathway that mediates brain Aβ clearance is the cerebrovascular system where Aβ is eliminated through the blood-brain barrier (BBB) and/or degraded by cerebrovascular cells along the interstitial fluid drainage pathway. An Aβ clearance receptor, the low-...

Systemic vascular function, measured with forearm flow mediated dilatation, in acute and stable cerebrovascular disease: a case-control study

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Blacker David

2010-10-01

Full Text Available Abstract Background Acute ischaemic stroke is associated with alteration in systemic markers of vascular function. We measured forearm vascular function (using forearm flow mediated dilatation to clarify whether recent acute ischaemic stroke/TIA is associated with impaired systemic vascular function. Methods Prospective case control study enrolling 17 patients with recent acute ischaemic stroke/TIA and 17 sex matched controls with stroke more than two years previously. Forearm vascular function was measured using flow medicated dilatation (FMD. Results Flow mediated dilatation was 6.0 ± 1.1% in acute stroke/TIA patients and 4.7 ± 1.0% among control subjects (p = 0.18. The mean paired difference in FMD between subjects with recent acute stroke and controls was 1.25% (95% CI -0.65, 3.14; p = 0.18. Endothelium independent dilatation was measured in six pairs of participants and was similar in acute stroke/TIA patients (22.6 ± 4.3% and control subjects (19.1 ± 2.6%; p = 0.43. Conclusions Despite the small size of this study, these data indicate that recent acute stroke is not necessarily associated with a clinically important reduction in FMD.

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

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Leon J. Schurgers

2018-04-01

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

Vascular Adventitia Calcification and Its Underlying Mechanism.

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Na Li

Full Text Available Previous research on vascular calcification has mainly focused on the vascular intima and media. However, we show here that vascular calcification may also occur in the adventitia. The purpose of this work is to help elucidate the pathogenic mechanisms underlying vascular calcification. The calcified lesions were examined by Von Kossa staining in ApoE-/- mice which were fed high fat diets (HFD for 48 weeks and human subjects aged 60 years and older that had died of coronary heart disease, heart failure or acute renal failure. Explant cultured fibroblasts and smooth muscle cells (SMCswere obtained from rat adventitia and media, respectively. After calcification induction, cells were collected for Alizarin Red S staining. Calcified lesions were observed in the aorta adventitia and coronary artery adventitia of ApoE-/-mice, as well as in the aorta adventitia of human subjects examined. Explant culture of fibroblasts, the primary cell type comprising the adventitia, was successfully induced for calcification after incubation with TGF-β1 (20 ng/ml + mineralization media for 4 days, and the phenotype conversion vascular adventitia fibroblasts into myofibroblasts was identified. Culture of SMCs, which comprise only a small percentage of all cells in the adventitia, in calcifying medium for 14 days resulted in significant calcification.Vascular calcification can occur in the adventitia. Adventitia calcification may arise from the fibroblasts which were transformed into myofibroblasts or smooth muscle cells.

Effects of serotonin on expression of the LDL receptor family member LR11 and 7-ketocholesterol-induced apoptosis in human vascular smooth muscle cells

Energy Technology Data Exchange (ETDEWEB)

Nagayama, Daiji; Ishihara, Noriko [Center of Diabetes, Endocrinology and Metabolism, Toho University, Sakura Medical Center, 564-1, Shimoshizu, Sakura-City, Chiba 285-8741 (Japan); Bujo, Hideaki [Department of Clinical Laboratory Medicine, Toho University, Sakura Medical Center, 564-1, Shimoshizu, Sakura-City, Chiba 285-8741 (Japan); Shirai, Kohji [Department of Vascular Function, Toho University, Sakura Medical Center, 564-1, Shimoshizu, Sakura-City, Chiba 285-8741 (Japan); Tatsuno, Ichiro, E-mail: ichiro.tatsuno@med.toho-u.ac.jp [Center of Diabetes, Endocrinology and Metabolism, Toho University, Sakura Medical Center, 564-1, Shimoshizu, Sakura-City, Chiba 285-8741 (Japan)

2014-04-18

Highlights: • The dedifferentiation of VSMCs in arterial intima is involved in atherosclerosis. • 5-HT showed proliferative effect on VSMCs which was abolished by sarpogrelate. • 5-HT enhanced expression of LR11 mRNA in VSMCs which was abolished by sarpogrelate. • 5-HT suppressed 7KCHO-induced apoptosis of VSMCs via caspase-3/7-dependent pathway. • The mechanisms explain the 5-HT-induced remodeling of arterial structure. - Abstract: Serotonin (5-HT) is a known mitogen for vascular smooth muscle cells (VSMCs). The dedifferentiation and proliferation/apoptosis of VSMCs in the arterial intima represent one of the atherosclerotic changes. LR11, a member of low-density lipoprotein receptor family, may contribute to the proliferation of VSMCs in neointimal hyperplasia. We conducted an in vitro study to investigate whether 5-HT is involved in LR11 expression in human VSMCs and apoptosis of VSMCs induced by 7-ketocholesterol (7KCHO), an oxysterol that destabilizes plaque. 5-HT enhanced the proliferation of VSMCs, and this effect was abolished by sarpogrelate, a selective 5-HT2A receptor antagonist. Sarpogrelate also inhibited the 5-HT-enhanced LR11 mRNA expression in VSMCs. Furthermore, 5-HT suppressed the 7KCHO-induced apoptosis of VSMCs via caspase-3/7-dependent pathway. These findings provide new insights on the changes in the differentiation stage of VSMCs mediated by 5-HT.

Compressive elasticity of three-dimensional nanofiber matrix directs mesenchymal stem cell differentiation to vascular cells with endothelial or smooth muscle cell markers.

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Wingate, K; Bonani, W; Tan, Y; Bryant, S J; Tan, W

2012-04-01

The importance of mesenchymal stem cells (MSC) in vascular regeneration is becoming increasingly recognized. However, few in vitro studies have been performed to identify the effects of environmental elasticity on the differentiation of MSC into vascular cell types. Electrospinning and photopolymerization techniques were used to fabricate a three-dimensional (3-D) polyethylene glycol dimethacrylate nanofiber hydrogel matrix with tunable elasticity for use as a cellular substrate. Compression testing demonstrated that the elastic modulus of the hydrated 3-D matrices ranged from 2 to 15 kPa, similar to the in vivo elasticity of the intima basement membrane and media layer. MSC seeded on rigid matrices (8-15 kPa) showed an increase in cell area compared with those seeded on soft matrices (2-5 kPa). Furthermore, the matrix elasticity guided the cells to express different vascular-specific phenotypes with high differentiation efficiency. Around 95% of MSC seeded on the 3-D matrices with an elasticity of 3 kPa showed Flk-1 endothelial markers within 24h, while only 20% of MSC seeded on the matrices with elasticity >8 kPa demonstrated Flk-1 marker. In contrast, ∼80% of MSC seeded on 3-D matrices with elasticity >8 kPa demonstrated smooth muscle α-actin marker within 24h, while fewer than 10% of MSC seeded on 3-D matrices with elasticity elasticity of the substrate could be a powerful tool for vascular tissue regeneration. Copyright © 2012 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Scale-adaptive surface modeling of vascular structures

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Ma Xin

2010-11-01

Full Text Available Abstract Background The effective geometric modeling of vascular structures is crucial for diagnosis, therapy planning and medical education. These applications require good balance with respect to surface smoothness, surface accuracy, triangle quality and surface size. Methods Our method first extracts the vascular boundary voxels from the segmentation result, and utilizes these voxels to build a three-dimensional (3D point cloud whose normal vectors are estimated via covariance analysis. Then a 3D implicit indicator function is computed from the oriented 3D point cloud by solving a Poisson equation. Finally the vessel surface is generated by a proposed adaptive polygonization algorithm for explicit 3D visualization. Results Experiments carried out on several typical vascular structures demonstrate that the presented method yields both a smooth morphologically correct and a topologically preserved two-manifold surface, which is scale-adaptive to the local curvature of the surface. Furthermore, the presented method produces fewer and better-shaped triangles with satisfactory surface quality and accuracy. Conclusions Compared to other state-of-the-art approaches, our method reaches good balance in terms of smoothness, accuracy, triangle quality and surface size. The vessel surfaces produced by our method are suitable for applications such as computational fluid dynamics simulations and real-time virtual interventional surgery.

Inferior vena cava leiomyosarcoma: vascular reconstruction is not ...

African Journals Online (AJOL)

... vena cava is a rare and aggressive tumor, arising from the smooth muscle cells in the vessel wall. A large complete surgical resection is the essential treatment. The need of vascular reconstruction is not always mandatory. It's above all to understand the place of the reconstruction with artificial vascular patch prosthetics of ...

Increased NBCn1 expression, Na⁺/HCO₃^– co-transport and intracellular pH in human vascular smooth muscle cells with a risk allele for hypertension

DEFF Research Database (Denmark)

Ng, Fu Liang; Boedtkjer, Ebbe; Witkowska, Katarzyna

2017-01-01

cultures of vascular smooth muscle and endothelial cells. In both cell types, we found genotype-dependent differences for rs13082711 in DNA-nuclear protein interactions, where the risk allele is associated with increased SLC4A7 expression level, NBCn1 availability and function as reflected in elevated...

Increased rhythmicity in hypertensive arterial smooth muscle is linked to transient receptor potential canonical channels

DEFF Research Database (Denmark)

Chen, Xiaoping; Yang, Dachun; Ma, Shuangtao

2010-01-01

Vasomotion describes oscillations of arterial vascular tone due to synchronized changes of intracellular calcium concentrations. Since increased calcium influx into vascular smooth muscle cells from spontaneously hypertensive rats (SHR) has been associated with variances of transient receptor pot...

Resveratrol Increases Serum BDNF Concentrations and Reduces Vascular Smooth Muscle Cells Contractility via a NOS-3-Independent Mechanism

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Michał Wiciński

2017-01-01

Full Text Available Resveratrol is a polyphenol that presents both antineuroinflammatory properties and the ability to interact with NOS-3, what contributes to vasorelaxation. Brain-derived neurotrophic factor (BNDF, a molecule associated with neuroprotection in many neurodegenerative disorders, is considered as an important element of maintaining stable cerebral blood flow. Vascular smooth muscle cells (VSMCs are considered to be an important element in the pathogenesis of neurodegeneration and a potential preventative target by agents which reduce the contractility of the vessels. Our main objectives were to define the relationship between serum and long-term oral resveratrol administration in the rat model, as well as to assess the effect of resveratrol on phenylephrine- (PHE- induced contraction of vascular smooth muscle cells (VSMCs. Moreover, we attempt to define the dependence of contraction mechanisms on endothelial NO synthase. Experiments were performed on Wistar rats (n=17 pretreated with resveratrol (4 weeks; 10 mg/kg p.o. or placebo. Serum BDNF levels were quantified after 2 and 4 weeks of treatment with ELISA. Contraction force was measured on isolated and perfused tail arteries as the increase of perfusion pressure with a constant flow. Values of serum BNDF in week 0 were 1.18±0.12 ng/mL (treated and 1.17±0.13 ng/mL (control (p = ns. After 2 weeks of treatment, BDNF in the treatment group was higher than in controls, 1.52±0.23 ng/mL and 1.24±0.13 ng/mL, respectively. (p=0.02 Following 4 weeks of treatment, BDNF values were higher in the resveratrol group compared to control 1.64±0.31 ng/mL and 1.32±0.26 ng/mL, respectively (p=0.031. EC50 values obtained for PHE in resveratrol pretreated arteries were significantly higher than controls (5.33±1.7 × 10−7 M/L versus 4.53±1.2 × 10−8 M/L, p<0.05. These results show a significant increase in BDNF concentration in the resveratrol pretreated group. The reactivity of resistant

Functional heterogeneity of NADPH oxidase-mediated contractions to endothelin with vascular aging.

Science.gov (United States)

Meyer, Matthias R; Barton, Matthias; Prossnitz, Eric R

2014-11-24

Aging, a physiological process and main risk factor for cardiovascular and renal diseases, is associated with endothelial cell dysfunction partly resulting from NADPH oxidase-dependent oxidative stress. Because increased formation of endothelium-derived endothelin-1 (ET-1) may contribute to vascular aging, we studied the role of NADPH oxidase function in age-dependent contractions to ET-1. Renal arteries and abdominal aortas from young and old C57BL6 mice (4 and 24 months of age) were prepared for isometric force measurements. Contractions to ET-1 (0.1-100 nmol/L) were determined in the presence and absence of the NADPH oxidase-selective inhibitor gp91ds-tat (3 μmol/L). To exclude age-dependent differential effects of NO bioactivity between vascular beds, all experiments were conducted in the presence of the NO synthase inhibitor L-NAME (300 μmol/L). In young animals, ET-1-induced contractions were 6-fold stronger in the renal artery than in the aorta (prenal artery and aorta, respectively (pAging had no effect on NADPH oxidase-dependent and -independent contractions to ET-1 in the renal artery. In contrast, contractions to ET-1 were markedly reduced in the aged aorta (5-fold, page-dependent heterogeneity of NADPH oxidase-mediated vascular contractions to ET-1, demonstrating an inherent resistance to functional changes in the renal artery but not in the aorta with aging. Thus, local activity of NADPH oxidase differentially modulates responses to ET-1 with aging in distinct vascular beds. Copyright © 2013 The Authors. Published by Elsevier Inc. All rights reserved.

Inhaled tolafentrine reverses pulmonary vascular remodeling via inhibition of smooth muscle cell migration

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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

45Ca distribution and transport in saponin skinned vascular smooth muscle

International Nuclear Information System (INIS)

Stout, M.A.; Diecke, F.P.

1983-01-01

45 Ca distribution and transport were studied in chemically skinned strips of caudal artery from Kyoto Wistar rats. Sarcolemmal membranes were made hyperpermeable by exposure for 60 min to solutions containing 0.1 mg/ml of saponin. Skinned helical strips responded with graded contractions to changes in ethylene glycol bis-(beta-aminoethyl ether)-N,N'-tetraacetic acid buffered free Ca solutions (10(-7) to 10(-5) M) and were sensitive to the Mg-ATP concentration. Tissues loaded in the presence of 10(-7) M Ca contracted in response to 10 mM caffeine. These experiments indicate the strips are skinned and possess a functional regulatory and contractile system and an intact Ca sequestering system. 45 Ca distributes in three compartments in skinned caudal artery strips. The Ca contents of two components are linear functions of the Ca-ethylene glycol bis-(beta-aminoethyl ether)-N,N'-tetraacetic acid concentration and desaturate at rapid rates. They correspond to the extracellular and cytoplasmic spaces. A significantly smaller component releases Ca at comparatively slower rates. 45 Ca uptake by the slow component consists of an ATP-dependent and an ATP-independent fraction. The 45 Ca content of the ATP-dependent fraction is a function of the free Ca concentration and is independent of the Ca-ethylene glycol bis-(beta-aminoethyl ether)-N,N'-tetraacetic acid concentration. Its content was enhanced by oxalate and was abolished by Triton X-100 skinning solutions. The ATP-independent component was not affected by Triton X-100 skinning and may represent Ca binding to cytoplasmic molecules and structures. The sequestered Ca was released with caffeine or Ca but not by epinephrine. The observations indicate that the sarcoplasmic reticulum and mitochondria of vascular smooth muscle strips skinned with saponin retain their functional integrity after saponin skinning

Increased NBCn1 expression, Na+/ HCO 3 ? co-transport and intracellular pH in human vascular smooth muscle cells with a risk allele for hypertension

OpenAIRE

Ng, Fu Liang; Boedtkjer, Ebbe; Witkowska, Kate; Ren, Meixia; Zhang, Ruoxin; Tucker, Arthur; Aalkj?r, Christian; Caulfield, Mark J.; Ye, Shu

2017-01-01

Abstract Genome-wide association studies have revealed an association between variation at the SLC4A7 locus and blood pressure. SLC4A7 encodes the electroneutral Na+/ HCO 3 ? co-transporter NBCn1 which regulates intracellular pH (pH i ). We conducted a functional study of variants at this locus in primary cultures of vascular smooth muscle and endothelial cells. In both cell types, we found genotype-dependent differences for rs13082711 in DNA-nuclear protein interactions, where the risk allel...

Strategies for improving chemotherapeutic delivery to solid tumors mediated by vascular permeability modulation

Science.gov (United States)

Roy Chaudhuri, Tista

An essential mode of distribution of blood-borne chemotherapeutic agents within a solid tumor is via the micro-circulation. Poor tumor perfusion, because of a lack of functional vasculature or a lack of microvessels, as well as low tumor vascular permeability, can prevent adequate deposition of even low molecular-weight agents into the tumor. The modulation of tumor vascular function and density can provides numerous strategies for improving intratumor deposition of chemotherapeutic agents. Here we investigated strategies to improve drug delivery to two tumor types that share in common poor drug delivery, but differ in the underlying cause. First, in an angiogenesis-driven brain tumor model of Glioblastoma, the vascular permeability barrier, along with poorly-functional vasculature, hinders drug delivery. A strategy of nanoparticle-based tumor 'priming' to attack the vascular permeability barrier, employing sterically stabilized liposomal doxorubicin (SSL-DXR), was investigated. Functional and histological evaluation of tumor vasculature revealed that after an initial period of depressed vascular permeability and vascular pruning 3--4 days after SSL-DXR administration, vascular permeability and perfusion were restored and then elevated after 5--7 days. As a result of tumor priming, deposition of subsequently-administered nanoparticles was enhanced, and the efficacy of temozolomide (TMZ), if administered during the window of elevated permeability, was increased. The sequenced regimen resulted in a persistent reduction of the tumor proliferative index and a 40% suppression of tumor volume, compared to animals that received both agents simultaneously. Second, in a hypovascular, pancreatic ductal adenocarcinoma model, disruption of tumor-stromal communication via sonic hedgehog (sHH) signaling pathway inhibition mediated an indirect vascular proliferation and a more than 2-fold increase in intratumor nanoparticle deposition. Enhanced delivery of SSL-DXR in tumors pre

Extracellular Matrix Molecules Facilitating Vascular Biointegration

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Martin K.C. Ng

2012-08-01

Full Text Available All vascular implants, including stents, heart valves and graft materials exhibit suboptimal biocompatibility that significantly reduces their clinical efficacy. A range of biomolecules in the subendothelial space have been shown to play critical roles in local regulation of thrombosis, endothelial growth and smooth muscle cell proliferation, making these attractive candidates for modulation of vascular device biointegration. However, classically used biomaterial coatings, such as fibronectin and laminin, modulate only one of these components; enhancing endothelial cell attachment, but also activating platelets and triggering thrombosis. This review examines a subset of extracellular matrix molecules that have demonstrated multi-faceted vascular compatibility and accordingly are promising candidates to improve the biointegration of vascular biomaterials.

Fetuin-A and albumin alter cytotoxic effects of calcium phosphate nanoparticles on human vascular smooth muscle cells.

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Yana Dautova

Full Text Available Calcification is a detrimental process in vascular ageing and in diseases such as atherosclerosis and arthritis. In particular, small calcium phosphate (CaP crystal deposits are associated with inflammation and atherosclerotic plaque de-stabilisation. We previously reported that CaP particles caused human vascular smooth muscle cell (VSMC death and that serum reduced the toxic effects of the particles. Here, we found that the serum proteins fetuin-A and albumin (≥ 1 µM reduced intracellular Ca2+ elevations and cell death in VSMCs in response to CaP particles. In addition, CaP particles functionalised with fetuin-A, but not albumin, were less toxic than naked CaP particles. Electron microscopic studies revealed that CaP particles were internalised in different ways; via macropinocytosis, membrane invagination or plasma membrane damage, which occurred within 10 minutes of exposure to particles. However, cell death did not occur until approximately 30 minutes, suggesting that plasma membrane repair and survival mechanisms were activated. In the presence of fetuin-A, CaP particle-induced damage was inhibited and CaP/plasma membrane interactions and particle uptake were delayed. Fetuin-A also reduced dissolution of CaP particles under acidic conditions, which may contribute to its cytoprotective effects after CaP particle exposure to VSMCs. These studies are particularly relevant to the calcification observed in blood vessels in patients with kidney disease, where circulating levels of fetuin-A and albumin are low, and in pathological situations where CaP crystal formation outweighs calcification-inhibitory mechanisms.

Kir2.1 regulates rat smooth muscle cell proliferation, migration, and post-injury carotid neointimal formation

International Nuclear Information System (INIS)

Qiao, Yong; Tang, Chengchun; Wang, Qingjie; Wang, Dong; Yan, Gaoliang; Zhu, Boqian

2016-01-01

Phenotype switching of vascular smooth muscle cells (VSMC) from the contractile type to the synthetic type is a hallmark of vascular disorders such as atherosclerosis and restenosis after angioplasty. Inward rectifier K"+ channel 2.1 (Kir2.1) has been identified in VSMC. However, whether it plays a functional role in regulating cellular transformation remains obscure. In this study, we evaluated the role of Kir2.1 on VSMC proliferation, migration, phenotype switching, and post-injury carotid neointimal formation. Kir2.1 knockdown significantly suppressed platelet-derived growth factor BB-stimulated rat vascular smooth muscle cells (rat-VSMC) proliferation and migration. Deficiency in Kir2.1 contributed to the restoration of smooth muscle α-actin, smooth muscle 22α, and calponin and to a reduction in osteopontin expression in rat-VSMC. Moreover, the in vivo study showed that rat-VSMC switched to proliferative phenotypes and that knockdown of Kir2.1 significantly inhibited neointimal formation after rat carotid injury. Kir2.1 may be a potential therapeutic target in the treatment of cardiovascular diseases, such as atherosclerosis and restenosis following percutaneous coronary intervention.

Kir2.1 regulates rat smooth muscle cell proliferation, migration, and post-injury carotid neointimal formation

Energy Technology Data Exchange (ETDEWEB)

Qiao, Yong; Tang, Chengchun, E-mail: tangchengchun@medmail.com.cn; Wang, Qingjie; Wang, Dong; Yan, Gaoliang; Zhu, Boqian

2016-09-02

Phenotype switching of vascular smooth muscle cells (VSMC) from the contractile type to the synthetic type is a hallmark of vascular disorders such as atherosclerosis and restenosis after angioplasty. Inward rectifier K{sup +} channel 2.1 (Kir2.1) has been identified in VSMC. However, whether it plays a functional role in regulating cellular transformation remains obscure. In this study, we evaluated the role of Kir2.1 on VSMC proliferation, migration, phenotype switching, and post-injury carotid neointimal formation. Kir2.1 knockdown significantly suppressed platelet-derived growth factor BB-stimulated rat vascular smooth muscle cells (rat-VSMC) proliferation and migration. Deficiency in Kir2.1 contributed to the restoration of smooth muscle α-actin, smooth muscle 22α, and calponin and to a reduction in osteopontin expression in rat-VSMC. Moreover, the in vivo study showed that rat-VSMC switched to proliferative phenotypes and that knockdown of Kir2.1 significantly inhibited neointimal formation after rat carotid injury. Kir2.1 may be a potential therapeutic target in the treatment of cardiovascular diseases, such as atherosclerosis and restenosis following percutaneous coronary intervention.

Effect of 103Pd on proliferation and apoptosis of vascular smooth muscle cells

International Nuclear Information System (INIS)

Luo Quanyong; Zhu Jun; Lu Hankui; Zhu Ruisen

2003-01-01

This study aimed at the effect of γ-emitting radionuclide 103 Pd on the proliferation and apoptosis of vascular SMCs (smooth muscle cells) in vitro. The cavy aortic SMCs were cultured with culture medium M-199. The experiments were carried out in two groups, one for proliferation test and the other for apoptosis test. In each group, 103 Pd solutions with various radioactivities were respectively added to the culture solution to irradiate SMCs for 72 h, while non-radioactive palladium solution was added to the control. 3 H-thymidine incorporation test and liquid scintillator were used to detect the effect of 103 Pd on the proliferation of SMCs. Flow cytometer was used to detect the apoptotic SMCs. The inhibition rate of SMCs proliferation by 1.85 MBq 103 Pd solution was 2.3%, which was not significant, while the inhibition rate increased from 41.6% to 91.3% as the 103 Pd activity increased from 7.40 MBq to 37 MBq. The apoptosis rate of SMCs was extremely low (less than 4.0%) by 103 Pd with activity from 1.85 MBq to 37 MBq. The results suggest that the proliferation of SMCs can be repressed effectively in a dose-dependent fashion by 103 Pd in vitro. The mechanism of its inhibiting over neointima proliferation is likely to inhibit SMCs proliferation rather than to induce its apoptosis by 103 Pd. 103 Pd can be used as a γ-emitting intravascular brachytherapy radionuclide to inhibit SMCs proliferation

Structural properties of lipid reconstructs and lipid composition of normotensive and hypertensive rat vascular smooth muscle cell membranes

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T.R. Oliveira

2009-09-01

Full Text Available Multiple cell membrane alterations have been reported to be the cause of various forms of hypertension. The present study focuses on the lipid portion of the membranes, characterizing the microviscosity of membranes reconstituted with lipids extracted from the aorta and mesenteric arteries of spontaneously hypertensive (SHR and normotensive control rat strains (WKY and NWR. Membrane-incorporated phospholipid spin labels were used to monitor the bilayer structure at different depths. The packing of lipids extracted from both aorta and mesenteric arteries of normotensive and hypertensive rats was similar. Lipid extract analysis showed similar phospholipid composition for all membranes. However, cholesterol content was lower in SHR arteries than in normotensive animal arteries. These findings contrast with the fact that the SHR aorta is hyporeactive while the SHR mesenteric artery is hyperreactive to vasopressor agents when compared to the vessels of normotensive animal strains. Hence, factors other than microviscosity of bulk lipids contribute to the vascular smooth muscle reactivity and hypertension of SHR. The excess cholesterol in the arteries of normotensive animal strains apparently is not dissolved in bulk lipids and is not directly related to vascular reactivity since it is present in both the aorta and mesenteric arteries. The lower cholesterol concentrations in SHR arteries may in fact result from metabolic differences due to the hypertensive state or to genes that co-segregate with those that determine hypertension during the process of strain selection.

TNF-α activates death pathway in human aorta smooth muscle cell in the presence of 7-ketocholesterol

International Nuclear Information System (INIS)

Lee, Hyun Sun; Chang, Jong Sun; Baek, Jin Ah; Chung, Mi Yeon; Lee, Han Cheol; Rhim, Byung Yong; Sok, Dai Eun; Rho, Mun-Chual; Kim, Young Kook; Kim, Koanhoi

2005-01-01

This study was undertaken to investigate whether a physiologically compatible concentration of 7-ketocholesterol had any effect on human vascular smooth muscle cells (HVSMCs). We found that 7-ketocholesterol changed the viability of human aorta smooth muscle cells (HAoSMC) not by cytotoxicity but by activation of tumor necrosis factor-α receptor (TNFR)-mediated death. Whereas TNF-α did not affect the viability in the presence of 7α-hydroxycholesterol or cholesterol, the cytokine induced HAoSMC death in the presence of 7-ketocholesterol as detected by morphology, viability, and fragmentation of chromosomal DNA. The HAoSMC death was inhibited by a neutralizing anti-TNF receptor 1 (TNFR1) antibody and by the caspase inhibitors of z-VAD and z-DEVD. Activations of caspase-8 and -3 were detected from dying HAoSMCs. 7-Ketocholesterol inhibited translocation of the nuclear factor κB (NF-κB) subunits of p65 and p50 from the cytosol into the nucleus, increase of NF-κB activity, and expression of caspase-8 homolog Fas ligand interleukin-1-converting enzyme inhibitory protein by TNF-α. We also found that X-chromosome-linked inhibitor of apoptosis protein was degraded in dying HAoSMC. The present study proposes that 7-ketocholesterol would contribute to the disappearance of HVSMC in the atherosclerotic lesions by enhancing receptor-mediated death. This is the first report demonstrating induction of TNF-α-mediated death by oxysterol in cells

Regulator of calcineurin 1 mediates pathological vascular wall remodeling

Science.gov (United States)

Esteban, Vanesa; Méndez-Barbero, Nerea; Jesús Jiménez-Borreguero, Luis; Roqué, Mercè; Novensá, Laura; Belén García-Redondo, Ana; Salaices, Mercedes; Vila, Luis; Arbonés, María L.

2011-01-01

Artery wall remodeling, a major feature of diseases such as hypertension, restenosis, atherosclerosis, and aneurysm, involves changes in the tunica media mass that reduce or increase the vessel lumen. The identification of molecules involved in vessel remodeling could aid the development of improved treatments for these pathologies. Angiotensin II (AngII) is a key effector of aortic wall remodeling that contributes to aneurysm formation and restenosis through incompletely defined signaling pathways. We show that AngII induces vascular smooth muscle cell (VSMC) migration and vessel remodeling in mouse models of restenosis and aneurysm. These effects were prevented by pharmacological inhibition of calcineurin (CN) or lentiviral delivery of CN-inhibitory peptides. Whole-genome analysis revealed >1,500 AngII-regulated genes in VSMCs, with just 11 of them requiring CN activation. Of these, the most sensitive to CN activation was regulator of CN 1 (Rcan1). Rcan1 was strongly activated by AngII in vitro and in vivo and was required for AngII-induced VSMC migration. Remarkably, Rcan1−/− mice were resistant to AngII-induced aneurysm and restenosis. Our results indicate that aneurysm formation and restenosis share mechanistic elements and identify Rcan1 as a potential therapeutic target for prevention of aneurysm and restenosis progression. PMID:21930771

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

Science.gov (United States)

Lin, Shigang; Mequanint, Kibret

2017-09-01

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

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

Energy Technology Data Exchange (ETDEWEB)

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

2015-07-17

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

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

International Nuclear Information System (INIS)

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

2015-01-01

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

Regulation and Roles of Urocortins in the Vascular System

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Kazunori Kageyama

2012-01-01

Full Text Available Urocortins (Ucns are members of the corticotropin-releasing factor (CRF family of peptides. Ucns would have potent effects on the cardiovascular system via the CRF receptor type 2 (CRF2 receptor. Regulation and roles of each Ucn have been determined in the vascular system. Ucns have more potent vasodilatory effects than CRF. Human umbilical vein endothelial cells (HUVECs express Ucns1-3 mRNAs, and the receptor, CRF2a receptor mRNA. Ucns1-3 mRNA levels are differentially regulated in HUVECs. Differential regulation of Ucns may suggest differential roles of those in HUVECs. Ucn1 and Ucn2 have strong effects on interleukin (IL-6 gene expression and secretion in rat aortic smooth muscle A7r5 cells. The increase that we observed in IL-6 levels following Ucn treatment of A7r5 cells suggests that smooth muscle cells may be a source of IL-6 secretion under physiological stress conditions. Ucns are important and unique modulators of vascular smooth muscle cells and act directly or indirectly as autocrine and paracrine factors in the vascular system.

Regulation of CCL5 expression in smooth muscle cells following arterial injury.

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Huan Liu

Full Text Available Chemokines play a crucial role in inflammation and in the pathophysiology of atherosclerosis by recruiting inflammatory immune cells to the endothelium. Chemokine CCL5 has been shown to be involved in atherosclerosis progression. However, little is known about how CCL5 is regulated in vascular smooth muscle cells. In this study we report that CCL5 mRNA expression was induced and peaked in aorta at day 7 and then declined after balloon artery injury, whereas IP-10 and MCP-1 mRNA expression were induced and peaked at day 3 and then rapidly declined.The expression of CCL5 receptors (CCR1, 3 & 5 were also rapidly induced and then declined except CCR5 which expression was still relatively high at day 14 after balloon injury. In rat smooth muscle cells (SMCs, similar as in aorta CCL5 mRNA expression was induced and kept increasing after LPS plus IFN-gamma stimulation, whereas IP-10 mRNA expression was rapidly induced and then declined. Our data further indicate that induction of CCL5 expression in SMCs was mediated by IRF-1 via binding to the IRF-1 response element in CCL5 promoter. Moreover, p38 MAPK was involved in suppression of CCL5 and IP-10 expression in SMCs through common upstream molecule MKK3. The downstream molecule MK2 was required for p38-mediated CCL5 but not IP-10 inhibition. Our findings indicate that CCL5 induction in aorta and SMCs is mediated by IRF-1 while activation of p38 MAPK signaling inhibits CCL5 and IP-10 expression. Methods targeting MK2 expression could be used to selectively regulate CCL5 but not IP-10 expression in SMCs.

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)

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

1985-01-01

Inositol 1,4,5-trisphosphate (IP3) rapidly increased 45 Ca 2+ 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 45 Ca 2+ release. Two nonhydrolyzable ATP analogues satisfied the nucleotide requirement for IP3-evoked 45 Ca 2+ release. IP3 strongly stimulated 45 Ca 2+ 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 45 Ca 2+ efflux suggests that IP3 activated a Ca 2+ channel, rather than a carrier, by a ligand-binding, rather than a metabolic, reaction

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

Science.gov (United States)

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

2015-06-01

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

Adiponectin attenuates angiotensin II-induced vascular smooth muscle cell remodeling through nitric oxide and the RhoA/ROCK pathway.

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Wared eNour-Eldine

2016-04-01

Full Text Available INTRODUCTION: Adiponectin (APN, an adipocytokine, exerts protective effects on cardiac remodeling, while angiotensin II (Ang II induces hypertension and vascular remodeling. The potential protective role of APN on the vasculature during hypertension has not been fully elucidated yet. Here, we evaluate the molecular mechanisms of the protective role of APN in the physiological response of the vascular wall to Ang II.METHODS AND RESULTS: Rat aortic tissues were used to investigate the effect of APN on Ang II-induced vascular remodeling and hypertrophy. We investigated whether nitric oxide (NO, the RhoA/ROCK pathway, actin cytoskeleton remodeling, and reactive oxygen species (ROS mediate the anti-hypertrophic effect of APN. Ang II-induced protein synthesis was attenuated by pre-treatment with APN, NO donor (SNAP, or cGMP. The hypertrophic response to Ang II was associated with a significant increase in RhoA activation and vascular force production, which were prevented by APN and SNAP. NO was also associated with inhibition of Ang II-induced phosphorylation of cofilin. In addition, immunohistochemistry revealed that 24 hr Ang II treatment increased the F- to G-actin ratio, an effect that was inhibited by SNAP. Ang II-induced ROS formation and upregulation of p22phox mRNA expression were inhibited by APN and NO. Both compounds failed to inhibit Nox1 and p47phox expression. CONCLUSIONS: Our results suggest that the anti-hypertrophic effects of APN are due, in part, to NO-dependent inhibition of the RhoA/ROCK pathway and ROS formation.

Erythroxylum pungens elicits vasorelaxation by reducing intracellular calcium concentration in vascular smooth muscle cells of rats

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Aurylene C. Oliveira

2012-01-01

Full Text Available The cardiovascular effects elicited by the ethanolic extract obtained from the roots of Erythroxylum pungens O.E. Schulz, Erythroxylaceae (EEEP and the vasorelaxant effect induced by its main tropane alkaloid (pungencine were investigated. In normotensive rats, administration of EEEP (1, 10, 30 and 60 mg/kg i.v., randomly produced dose-dependent hypotension (-2±1, -7±0.5 -17.6±1, -24±1 Δ mmHg, n=5 followed by tachycardia (3±0.5, 7±2, 7.1±1, 10±5 Δ bpm, n=5. In intact phenylephrine (Phe, 10 µM-pre-contracted rings, EEEP (0.01-500 µg/mL induced concentration-dependent vasorelaxation (EC50 13.7±5.5 µg/mL, Maximal Response= 92±2.6%, and this effect was unchanged after the removal of the vascular endothelium (EC50 27.2±4.7 µg/ml, Maximal Response= 88.3±3.3 %. In KCl (80 mM-pre-contracted-endothelium-denuded rings, EEEP elicited concentration-dependent relaxation (EC50= 128.2±11.2 µg/mL, Maximal Response 76.8±3.4%. Vasorelaxation has also been achieved with tonic contractions evoked by the L-type Ca2+ channel agonist Bay K 8644 (EC50 80.2±9.1 µg/mL, Maximal Response 86.3±8.3%. In addition, in a depolarizing medium, EEEP inhibited CaCl2 (30-500 µg/mL induced contractions and caused a concentration-dependent rightward shift of the relaxation curves. Lastly, the tropane alkaloid pungencine caused vasorelaxation in mesenteric arteries resembling to the EEEP responses. These results suggests that EEEP induces hypotension and vasorelaxation, at least in part, due to the reduction in [Ca2+]i in vascular smooth muscle cells.

Magnolol inhibits migration of vascular smooth muscle cells via cytoskeletal remodeling pathway to attenuate neointima formation

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Karki, Rajendra; Kim, Seong-Bin; Kim, Dong-Wook

2013-01-01

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

Magnolol inhibits migration of vascular smooth muscle cells via cytoskeletal remodeling pathway to attenuate neointima formation

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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

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

International Nuclear Information System (INIS)

Curtis, Brandon M.; Leix, Kyle Alexander; Ji, Yajing; Glaves, Richard Samuel Elliot; Ash, David E.; Mohanty, Dillip K.

2014-01-01

Highlights: • Multipotent vascular stem cells (MVSCs) proliferate and differentiate. • Nitric oxide inhibits proliferation of MVSCs. • Nitric oxide inhibits MVSC differentiation to mesenchymal-like stem cells (MSCs). • Smooth muscle cells (SMCs) neither de-differentiate nor proliferate. - Abstract: Atherosclerosis is the leading cause of cerebral and myocardial infarction. It is believed that neointimal growth common in the later stages of atherosclerosis is a result of vascular smooth muscle cell (SMC) de-differentiation in response to endothelial injury. However, the claims of the SMC de-differentiation theory have not been substantiated by monitoring the fate of mature SMCs in response to such injuries. A recent study suggests that atherosclerosis is a consequence of multipotent vascular stem cell (MVSC) differentiation. Nitric oxide (NO) is a well-known mediator against atherosclerosis, in part because of its inhibitory effect on SMC proliferation. Using three different NO-donors, we have investigated the effects of NO on MVSC proliferation. Results indicate that NO inhibits MVSC proliferation in a concentration dependent manner. A slow and sustained delivery of NO proved to inhibit proliferation without causing cell death. On the other hand, larger, single-burst NO concentrations, inhibits proliferation, with concurrent significant cell death. Furthermore, our results indicate that endogenously produced NO inhibits MVSC differentiation to mesenchymal-like stem cells (MSCs) and subsequently to SMC as well

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.

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

NARCIS (Netherlands)

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

1996-01-01

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

The chemokine and scavenger receptor CXCL16/SR-PSOX is expressed in human vascular smooth muscle cells and is induced by interferon γ

International Nuclear Information System (INIS)

Wagsaeter, Dick; Olofsson, Peder S.; Norgren, Lars; Stenberg, Bjoern; Sirsjoe, Allan

2004-01-01

Atherosclerosis is an inflammatory disease that is characterised by the involvement of chemokines that are important for the recruitment of leukocytes and scavenger receptors that mediate foam cell formation. Several cytokines are involved in the regulation of chemokines and scavenger receptors in atherosclerosis. CXCL16 is a chemokine and scavenger receptor and found in macrophages in human atherosclerotic lesions. Using double-labelled immunohistochemistry, we identified that smooth muscle cells in human lesions express CXCL16. We then analysed the effects of IFN-γ, TNF-α, IL-12, IL-15, IL-18, and LPS on CXCL16 expression in cultured aortic smooth muscle cells. IFN-γ was the most potent CXCL16 inducer and increased mRNA, soluble form, membrane form, and total cellular levels of CXCL16. The IFN-γ induction of CXCL16 was also associated with increased uptake of oxLDL into these cells. Taken together, smooth muscle cells express CXCL16 in atherosclerotic lesions, which may play a role in the attraction of T cells to atherosclerotic lesions and contribute to the cellular internalisation of modified LDL

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

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Junxi Wu

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

Effect of uric acid on inflammatory COX-2 and ROS pathways in vascular smooth muscle cells.

Science.gov (United States)

Oğuz, Nurgül; Kırça, Mustafa; Çetin, Arzu; Yeşilkaya, Akın

2017-10-01

Hyperuricemia is thought to play a role in cardiovascular diseases (CVD), including hypertension, coronary artery disease and atherosclerosis. However, exactly how uric acid contributes to these pathologies is unknown. An underlying mechanism of inflammatory diseases, such as atherosclerosis, includes enhanced production of cyclooxygenase-2 (COX-2) and superoxide anion. Here, we aimed to examine the effect of uric acid on inflammatory COX-2 and superoxide anion production and to determine the role of losartan. Primarily cultured vascular smooth muscle cells (VSMCs) were time and dose-dependently induced by uric acid and COX-2 and superoxide anion levels were measured. COX-2 levels were determined by ELISA, and superoxide anion was measured by the superoxide dismutase (SOD)-inhibitable reduction of ferricytochrome c method. Uric acid elevated COX-2 levels in a time-dependent manner. Angiotensin-II receptor blocker, losartan, diminished uric-acid-induced COX-2 elevation. Uric acid also increased superoxide anion level in VSMCs. Uric acid plays an important role in CVD pathogenesis by inducing inflammatory COX-2 and ROS pathways. This is the first study demonstrating losartan's ability to reduce uric-acid-induced COX-2 elevation.

Flow-mediated dilation: can new approaches provide greater mechanistic insight into vascular dysfunction in preeclampsia and other diseases?

Science.gov (United States)

Weissgerber, Tracey L

2014-11-01

Endothelial dysfunction is a key feature of preeclampsia and may contribute to increased cardiovascular disease risk years after pregnancy. Flow-mediated dilation (FMD) is a non-invasive endothelial function test that predicts cardiovascular event risk. New protocols allow researchers to measure three components of the FMD response: FMD, low flow-mediated constriction, and shear stimulus. This review encourages researchers to think beyond "low FMD" by examining how these three components may provide additional insights into the mechanisms and location of vascular dysfunction. The review then examines what FMD studies reveal about vascular dysfunction in preeclampsia while highlighting opportunities to gain greater mechanistic insight from new protocols. Studies using traditional protocols show that FMD is low in mid-pregnancy prior to preeclampsia, at diagnosis, and for 3 years post-partum. However, FMD returns to normal by 10 years post-partum. Studies using new protocols are needed to gain more mechanistic insight.

The in vivo blood compatibility of bio-inspired small diameter vascular graft: effect of submicron longitudinally aligned topography

Science.gov (United States)

2013-01-01

Background Cardiovascular disease is the leading cause of deaths worldwide and the arterial reconstructive surgery remains the treatment of choice. Although large diameter vascular grafts have been widely used in clinical practices, there is an urgent need to develop a small diameter vascular graft with enhanced blood compatibility. Herein, we fabricated a small diameter vascular graft with submicron longitudinally aligned topography, which mimicked the tunica intima of the native arterial vessels and were tested in Sprague–Dawley (SD) rats. Methods Vascular grafts with aligned and smooth topography were prepared by electrospinning and were connected to the abdominal aorta of the SD rats to evaluate their blood compatibility. Graft patency and platelet adhesion were evaluated by color Doppler ultrasound and immunofluorescence respectively. Results We observed a significant higher patency rate (p = 0.021) and less thrombus formation in vascular graft with aligned topography than vascular graft with smooth topography. However, no significant difference between the adhesion rates on both vascular grafts (smooth/aligned: 0.35‰/0.12‰, p > 0.05) was observed. Moreover, both vascular grafts had few adherent activated platelets on the luminal surface. Conclusion Bionic vascular graft showed enhanced blood compatibility due to the effect of surface topography. Therefore, it has considerable potential for using in clinical application. PMID:24083888

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

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Guo Yingqiang

2010-05-01

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

The combination of lanthanum chloride and the calcimimetic calindol delays the progression of vascular smooth muscle cells calcification

Energy Technology Data Exchange (ETDEWEB)

Ciceri, Paola; Volpi, Elisa; Brenna, Irene; Elli, Francesca [Renal Division and Laboratory of Experimental Nephrology, Dipartimento di Medicina e Chirurgia, Universita di Milano, Milan (Italy); Borghi, Elisa [Dipartimento di Salute Pubblica, Microbiologia e Virologia, Universita di Milano, Milan (Italy); Brancaccio, Diego [Renal Division and Laboratory of Experimental Nephrology, Dipartimento di Medicina e Chirurgia, Universita di Milano, Milan (Italy); Cozzolino, Mario, E-mail: mario.cozzolino@unimi.it [Renal Division and Laboratory of Experimental Nephrology, Dipartimento di Medicina e Chirurgia, Universita di Milano, Milan (Italy)

2012-02-24

Highlights: Black-Right-Pointing-Pointer Lanthanum reduces the progression of high phosphate-induced calcium deposition. Black-Right-Pointing-Pointer Calcium receptor agonists and the calcimimetic calindol reduce calcium deposition. Black-Right-Pointing-Pointer Lanthanum and calindol cooperate on reducing calcium deposition. Black-Right-Pointing-Pointer Lanthanum and calindol may interact with the same receptor. -- Abstract: Phosphate (Pi)-binders are commonly used in dialysis patients to control high Pi levels, that associated with vascular calcification (VC). The aim of this study was to investigate the effects of lanthanum chloride (LaCl{sub 3}) on the progression of high Pi-induced VC, in rat vascular smooth muscle cells (VSMCs). Pi-induced Ca deposition was inhibited by LaCl{sub 3}, with a maximal effect at 100 {mu}M (59.0 {+-} 2.5% inhibition). Furthermore, we studied the effects on VC of calcium sensing receptor (CaSR) agonists. Gadolinium chloride, neomycin, spermine, and the calcimimetic calindol significantly inhibited Pi-induced VC (55.9 {+-} 2.2%, 37.3 {+-} 4.7%, 30.2 {+-} 5.7%, and 63.8 {+-} 5.7%, respectively). To investigate the hypothesis that LaCl{sub 3} reduces the progression of VC by interacting with the CaSR, we performed a concentration-response curve of LaCl{sub 3} in presence of a sub-effective concentration of calindol (10 nM). Interestingly, this curve was shifted to the left (IC{sub 50} 9.6 {+-} 2.6 {mu}M), compared to the curve in the presence of LaCl{sub 3} alone (IC{sub 50} 19.0 {+-} 4.8 {mu}M). In conclusion, we demonstrated that lanthanum chloride effectively reduces the progression of high phosphate-induced vascular calcification. In addition, LaCl{sub 3} cooperates with the calcimimetic calindol in decreasing Ca deposition in this in vitro model. These results suggest the potential role of lanthanum in the treatment of VC induced by high Pi.

Myostatin, a profibrotic factor and the main inhibitor of striated muscle mass, is present in the penile and vascular smooth muscle.

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Kovanecz, I; Masouminia, M; Gelfand, R; Vernet, D; Rajfer, J; Gonzalez-Cadavid, N F

2017-09-01

Myostatin is present in striated myofibers but, except for myometrial cells, has not been reported within smooth muscle cells (SMC). We investigated in the rat whether myostatin is present in SMC within the penis and the vascular wall and, if so, whether it is transcriptionally expressed and associated with the loss of corporal SMC occurring in certain forms of erectile dysfunction (ED). Myostatin protein was detected by immunohistochemistry/fluorescence and western blots in the perineal striated muscles, and also in the SMC of the penile corpora, arteries and veins, and aorta. Myostatin was found in corporal SMC cultures, and its transcriptional expression (and its receptor) was shown there by DNA microarrays. Myostatin protein was measured by western blots in the penile shaft of rats subjected to bilateral cavernosal nerve resection (BCNR), that were left untreated, or treated (45 days) with muscle-derived stem cells (MDSC), or concurrent daily low-dose sildenafil. Myostatin was not increased by BCNR (compared with sham operated animals), but over expressed after treatment with MDSC. This was reduced by concurrent sildenafil. The presence of myostatin in corporal and vascular SMC, and its overexpression in the corpora by MDSC therapy, may have relevance for the stem cell treatment of corporal fibrosis and ED.

Neuronally mediated contraction responses of guinea-pig stomach smooth muscle preparations: modification by benzamide derivatives does not reflect a dopamine antagonist action.

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Costall, B; Naylor, R J; Tan, C C

1984-06-15

The actions of the substituted benzamide derivatives metoclopramide, clebopride, YM-09151-2, tiapride, (+)- and (-)-sulpiride and (+)- and (-)-sultopride, and the dopamine antagonists haloperidol and domperidone, were studied on the responses to field stimulation (0.125-10 Hz) of smooth muscle strips taken from cardia, fundus, body and antral regions of the longitudinal and circular muscle of guinea-pig stomach. Field stimulation of the longitudinal strips caused contraction responses which were antagonised by atropine (but not by prazosin, yohimbine, propranolol or methysergide) to indicate a muscarinic cholinergic involvement. Antagonism of the contractions revealed or enhanced relaxation responses mediated via unidentified mechanisms (resistant to cholinergic and adrenergic antagonists). Metoclopramide enhanced the field stimulation-induced contractions of the stomach smooth muscle preparations via atropine sensitive mechanisms but failed to attenuate the field stimulation-induced relaxation responses. Clebopride's action closely followed that of metoclopramide but YM-09151-2 only enhanced the contraction responses of the longitudinal muscle preparations. Other dopamine antagonists, (+)- and (-)-sulpiride, (+)- and (-)-sultopride, tiapride, haloperidol and domperidone failed to facilitate contraction to field stimulation of any stomach tissue. Thus, the actions of metoclopramide, clebopride and YM-09151-2 to facilitate contraction to field stimulation of stomach smooth muscle are mediated via a muscarinic cholinergic mechanism and are not the consequence of an antagonism at any recognisable dopamine receptor.

Aberrant Splicing Induced by Dysregulated Rbfox2 Produces Enhanced Function of CaV1.2 Calcium Channel and Vascular Myogenic Tone in Hypertension.

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Zhou, Yingying; Fan, Jia; Zhu, Huayuan; Ji, Li; Fan, Wenyong; Kapoor, Isha; Wang, Yue; Wang, Yuan; Zhu, Guoqing; Wang, Juejin

2017-12-01

Calcium influx from activated voltage-gated calcium channel Ca V 1.2 in vascular smooth muscle cells is indispensable for maintaining myogenic tone and blood pressure. The function of Ca V 1.2 channel can be optimized by alternative splicing, one of post-transcriptional modification mechanisms. The splicing factor Rbfox2 is known to regulate the Ca V 1.2 pre-mRNA alternative splicing events during neuronal development. However, Rbfox2's roles in modulating the key function of vascular Ca V 1.2 channel and in the pathogenesis of hypertension remain elusive. Here, we report that the proportion of Ca V 1.2 channels with alternative exon 9* is increased by 10.3%, whereas that with alternative exon 33 is decreased by 10.5% in hypertensive arteries. Surprisingly, the expression level of Rbfox2 is increased ≈3-folds, presumably because of the upregulation of a dominant-negative isoform of Rbfox2. In vascular smooth muscle cells, we find that knockdown of Rbfox2 dynamically increases alternative exon 9*, whereas decreases exon 33 inclusion of Ca V 1.2 channels. By patch-clamp studies, we show that diminished Rbfox2-induced alternative splicing shifts the steady-state activation and inactivation curves of vascular Ca V 1.2 calcium channel to hyperpolarization, which makes the window current potential to more negative. Moreover, siRNA-mediated knockdown of Rbfox2 increases the pressure-induced vascular myogenic tone of rat mesenteric artery. Taken together, our data indicate that Rbfox2 modulates the functions of vascular Ca V 1.2 calcium channel by dynamically regulating the expressions of alternative exons 9* and 33, which in turn affects the vascular myogenic tone. Therefore, our work suggests a key role for Rbfox2 in hypertension, which provides a rational basis for designing antihypertensive therapies. © 2017 American Heart Association, Inc.

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

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

2015-05-01

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

Epigallocatechin Gallate Attenuates Proliferation and Oxidative Stress in Human Vascular Smooth Muscle Cells Induced by Interleukin-1β via Heme Oxygenase-1

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Po-Len Liu

2014-01-01

Full Text Available Proliferation of vascular smooth muscle cells (VSMCs triggered by inflammatory stimuli and oxidative stress contributes importantly to atherogenesis. The association of green tea consumption with cardiovascular protection has been well documented in epidemiological observations, however, the underlying mechanisms remain unclear. This study aimed to elucidate the effects of the most active green tea catechin derivative, (−-epigallocatechin-3-gallate (EGCG, in human aortic smooth muscle cells (HASMCs, focusing particularly on the role of a potent anti-inflammatory and antioxidative enzyme heme oxygenase-1 (HO-1. We found that pretreatment of EGCG dose- and time-dependently induced HO-1 protein levels in HASMCs. EGCG inhibited interleukin- (IL-1β-induced HASMC proliferation and oxidative stress in a dose-dependent manner. The HO-1 inducer CoPPIX decreased IL-1β-induced cell proliferation, whereas the HO-1 enzyme inhibitor ZnPPIX significantly reversed EGCG-caused growth inhibition in IL-1β-treated HASMCs. At the molecular level, EGCG treatment significantly activated nuclear factor erythroid-2-related factor (Nrf2 transcription activities. These results suggest that EGCG might serve as a complementary and alternative medicine in the treatment of these pathologies by inducing HO-1 expression and subsequently decreasing VSMC proliferation.

NONOates regulate KCl cotransporter-1 and -3 mRNA expression in vascular smooth muscle cells.

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Di Fulvio, Mauricio; Lauf, Peter K; Shah, Shalin; Adragna, Norma C

2003-05-01

Nitric oxide (NO) donors regulate KCl cotransport (KCC) activity and cotransporter-1 and -3 (KCC1 and KCC3) mRNA expression in sheep erythrocytes and in primary cultures of rat vascular smooth muscle cells (VSMCs), respectively. In this study, we used NONOates as rapid and slow NO releasers to provide direct evidence implicating NO as a regulator of KCC3 gene expression at the mRNA level. In addition, we used the expression of KCC3 mRNA to further investigate the mechanism of action of these NO donors at the cellular level. Treatment of VSMCs with rapid NO releasers, like NOC-5 and NOC-9, as well as with the direct NO-independent soluble guanylyl cyclase (sGC) stimulator YC-1, acutely increased KCC3 mRNA expression in a concentration- and time-dependent manner. The slow NO releaser NOC-18 had no effect on KCC3 gene expression. A specific NO scavenger completely prevented the NONOate-induced KCC3 mRNA expression. Inhibition of sGC with LY-83583 blocked the NONOate- and YC-1-induced KCC3 mRNA expression. This study shows that in primary cultures of rat VSMCs, the fast NO releasers NOC-9 and NOC-5, but not the slow NO releaser NOC-18, acutely upregulate KCC3 mRNA expression in a NO/sGC-dependent manner.

Aspirin-triggered resolvin D1 attenuates PDGF-induced vascular smooth muscle cell migration via the cyclic adenosine monophosphate/protein kinase A (cAMP/PKA) pathway.

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Mottola, Giorgio; Chatterjee, Anuran; Wu, Bian; Chen, Mian; Conte, Michael S

2017-01-01

Resolvin D1 (RvD1) is a specialized pro-resolving lipid mediator that has been previously shown to attenuate vascular smooth muscle cell (VSMC) migration, a key process in the development of intimal hyperplasia. We sought to investigate the role of the cAMP/PKA pathway in mediating the effects of the aspirin-triggered epimer 17R-RvD1 (AT-RvD1) on VSMC migration. VSMCs were harvested from human saphenous veins. VSMCs were analyzed for intracellular cAMP levels and PKA activity after exposure to AT-RvD1. Platelet-derived growth factor (PDGF)-induced migration and cytoskeletal changes in VSMCs were observed through scratch, Transwell, and cell shape assays in the presence or absence of a PKA inhibitor (Rp-8-Br-cAMP). Further investigation of the pathways involved in AT-RvD1 signaling was performed by measuring Rac1 activity, vasodilator stimulated phosphoprotein (VASP) phosphorylation and paxillin translocation. Finally, we examined the role of RvD1 receptors (GPR32 and ALX/FPR2) in AT-RvD1 induced effects on VSMC migration and PKA activity. Treatment with AT-RvD1 induced a significant increase in cAMP levels and PKA activity in VSMCs at 5 minutes and 30 minutes, respectively. AT-RvD1 attenuated PDGF-induced VSMC migration and cytoskeletal rearrangements. These effects were attenuated by the PKA inhibitor Rp-8-Br-cAMP, suggesting cAMP/PKA involvement. Treatment of VSMC with AT-RvD1 inhibited PDGF-stimulated Rac1 activity, increased VASP phosphorylation, and attenuated paxillin localization to focal adhesions; these effects were negated by the addition of Rp-8-Br-cAMP. The effects of AT-RvD1 on VSMC migration and PKA activity were attenuated by blocking ALX/FPR2, suggesting an important role of this G-protein coupled receptor. Our results suggest that AT-RvD1 attenuates PDGF-induced VSMC migration via ALX/FPR2 and cAMP/PKA. Interference with Rac1, VASP and paxillin function appear to mediate the downstream effects of AT-RvD1 on VSMC migration.

Chronic Prenatal Hypoxia Down-Regulated BK Channel Β1 Subunits in Mesenteric Artery Smooth Muscle Cells of the Offspring

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Bailin Liu

2018-02-01

Full Text Available Background/Aims: Chronic hypoxia in utero could impair vascular functions in the offspring, underlying mechanisms are unclear. This study investigated functional alteration in large-conductance Ca2+-activated K+ (BK channels in offspring mesenteric arteries following prenatal hypoxia. Methods: Pregnant rats were exposed to normoxic control (21% O2, Con or hypoxic (10.5% O2, Hy conditions from gestational day 5 to 21, their 7-month-old adult male offspring were tested for blood pressure, vascular BK channel functions and expression using patch clamp and wire myograh technique, western blotting, and qRT-PCR. Results: Prenatal hypoxia increased pressor responses and vasoconstrictions to phenylephrine in the offspring. Whole-cell currents density of BK channels and amplitude of spontaneous transient outward currents (STOCs, not the frequency, were significantly reduced in Hy vascular myocytes. The sensitivity of BK channels to voltage, Ca2+, and tamoxifen were reduced in Hy myocytes, whereas the number of channels per patch and the single-channel conductance were unchanged. Prenatal hypoxia impaired NS1102- and tamoxifen-mediated relaxation in mesenteric arteries precontracted with phenylephrine in the presence of Nω-nitro-L-arginine methyl ester. The mRNA and protein expression of BK channel β1, not the α-subunit, was decreased in Hy mesenteric arteries. Conclusions: Impaired BK channel β1-subunits in vascular smooth muscle cells contributed to vascular dysfunction in the offspring exposed to prenatal hypoxia.

Biomaterial-mediated strategies targeting vascularization for bone repair.

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García, José R; García, Andrés J

2016-04-01

Repair of non-healing bone defects through tissue engineering strategies remains a challenging feat in the clinic due to the aversive microenvironment surrounding the injured tissue. The vascular damage that occurs following a bone injury causes extreme ischemia and a loss of circulating cells that contribute to regeneration. Tissue-engineered constructs aimed at regenerating the injured bone suffer from complications based on the slow progression of endogenous vascular repair and often fail at bridging the bone defect. To that end, various strategies have been explored to increase blood vessel regeneration within defects to facilitate both tissue-engineered and natural repair processes. Developments that induce robust vascularization will need to consolidate various parameters including optimization of embedded therapeutics, scaffold characteristics, and successful integration between the construct and the biological tissue. This review provides an overview of current strategies as well as new developments in engineering biomaterials to induce reparation of a functional vascular supply in the context of bone repair.

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

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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

Heterogeneity of smooth muscle cells in tunica media of aorta in ...

African Journals Online (AJOL)

... of the tunica media of goat aorta are phenotypically heterogeneous and run in multiple directions. These characteristics probably confer mechanical strength and functional plasticity to the aortic wall. Designers of aortic substitutes should bear this in mind. Keywords: Vascular, Smooth Muscle Cells, Heterogeneity, Aorta ...

Identification of pathogenicity-related genes in the vascular wilt fungus verticillium dahliae by agrobacterium tumefaciens-mediated t-DNA insertional mutagenesis.

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Verticillium dahliae is the causal agent of vascular wilt in many economically important crops worldwide. Identification of genes that underpin pathogenicity or virulence may suggest targets for alternative control methods for this fungus. In this study, Agrobacterium tumefaciens-mediated transform...

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

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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...

Junctional transfer in cultured vascular endothelium: II. Dye and nucleotide transfer

International Nuclear Information System (INIS)

Larson, D.M.; Sheridan, J.D.

1985-01-01

Vascular endothelial cultures, derived from large vessels, retain many of the characteristics of their in vivo counterparts. However, the observed reduction in size and complexity of intercellular gap and tight junctions in these cultured cells suggests that important functions, thought to be mediated by these structures, may be altered in vitro. In continuing studies on intercellular communication in vessel wall cells, the authors have quantitated the extent of junctional transfer of small molecular tracers (the fluorescent dye Lucifer Yellow CH and tritiated uridine nucleotides) in confluent cultures of calf aortic (BAEC) and umbilical vein (BVEC) endothelium. Both BAEC and BVEC show extensive (and quantitatively equivalent) dye and nucleotide transfer. As an analogue of intimal endothelium, the authors have also tested dye transfer in freshly isolated sheets of endothelium. Transfer in BAEC and BVEC sheets was more rapid, extensive and homogeneous than in the cultured cells, implying a reduction in molecular coupling as endothelium adapts to culture conditions. In addition, they have documented heterocellular nucleotide transfer between cultured endothelium and vascular smooth muscle cells, of particular interest considering the prevalence of ''myo-endothelial'' junctions in vivo. These data yield further information on junctional transfer in cultured vascular endothelium and have broad implications for the functional integration of the vessel wall in the physiology and pathophysiology of the vasculature

Vascular dysfunction by myofibroblast activation in patients with idiopathic pulmonary fibrosis and prognostic significance

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E.R. Parra

2012-07-01

Full Text Available In this study, we demonstrated the importance of telomerase protein expression and determined the relationships among telomerase, endothelin-1 (ET-1 and myofibroblasts during early and late remodeling of parenchymal and vascular areas in usual interstitial pneumonia (UIP using 27 surgical lung biopsies from patients with idiopathic pulmonary fibrosis (IPF. Telomerase+, myofibroblasts α-SMA+, smooth muscle cells caldesmon+, endothelium ET-1+ cellularity, and fibrosis severity were evaluated in 30 fields covering normal lung parenchyma, minimal fibrosis (fibroblastic foci, severe (mural fibrosis, and vascular areas of UIP by the point-counting technique and a semiquantitative score. The impact of these markers was determined in pulmonary functional tests and follow-up until death from IPF. Telomerase and ET-1 expression was significantly increased in normal and vascular areas compared to areas of fibroblast foci. Telomerase and ET-1 expression was inversely correlated with minimal fibrosis in areas of fibroblast foci and directly associated with severe fibrosis in vascular areas. Telomerase activity in minimal fibrosis areas was directly associated with diffusing capacity of the lung for oxygen/alveolar volume and ET-1 expression and indirectly associated with diffusing capacity of the lungs for carbon monoxide and severe fibrosis in vascular areas. Cox proportional hazards regression revealed a low risk of death for females with minimal fibrosis displaying high telomerase and ET-1 expression in normal areas. Vascular dysfunction by telomerase/ET-1 expression was found earlier than vascular remodeling by myofibroblast activation in UIP with impact on IPF evolution, suggesting that strategies aimed at preventing the effect of these mediators may have a greater impact on patient outcome.

Transcriptional Regulation of S Phase Kinase-associated Protein 2 by NR4A Orphan Nuclear Receptor NOR1 in Vascular Smooth Muscle Cells*

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Gizard, Florence; Zhao, Yue; Findeisen, Hannes M.; Qing, Hua; Cohn, Dianne; Heywood, Elizabeth B.; Jones, Karrie L.; Nomiyama, Takashi; Bruemmer, Dennis

2011-01-01

Members of the NR4A subgroup of the nuclear hormone receptor superfamily have emerged as key transcriptional regulators of proliferation and inflammation. NOR1 constitutes a ligand-independent transcription factor of this subgroup and induces cell proliferation; however, the transcriptional mechanisms underlying this mitogenic role remain to be defined. Here, we demonstrate that the F-box protein SKP2 (S phase kinase-associated protein 2), the substrate-specific receptor of the ubiquitin ligase responsible for the degradation of p27KIP1 through the proteasome pathway, constitutes a direct transcriptional target for NOR1. Mitogen-induced Skp2 expression is silenced in vascular smooth muscle cells (VSMC) isolated from Nor1-deficient mice or transfected with Nor1 siRNA. Conversely, adenovirus-mediated overexpression of NOR1 induces Skp2 expression in VSMC and decreases protein abundance of its target p27. Transient transfection experiments establish that NOR1 transactivates the Skp2 promoter through a nerve growth factor-induced clone B response element (NBRE). Electrophoretic mobility shift and chromatin immunoprecipitation assays further revealed that NOR1 is recruited to this NBRE site in the Skp2 promoter in response to mitogenic stimulation. In vivo Skp2 expression is increased during the proliferative response underlying neointima formation, and this transcriptional induction depends on the expression of NOR1. Finally, we demonstrate that overexpression of Skp2 rescues the proliferative arrest of Nor1-deficient VSMC. Collectively, these results characterize Skp2 as a novel NOR1-regulated target gene and detail a previously unrecognized transcriptional cascade regulating mitogen-induced VSMC proliferation. PMID:21868379

Vascular Remodeling in Experimental Hypertension

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Norma R. Risler

2005-01-01

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

The Complex Role of Store Operated Calcium Entry Pathways and Related Proteins in the Function of Cardiac, Skeletal and Vascular Smooth Muscle Cells

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Javier Avila-Medina

2018-03-01

Full Text Available Cardiac, skeletal, and smooth muscle cells shared the common feature of contraction in response to different stimuli. Agonist-induced muscle's contraction is triggered by a cytosolic free Ca2+ concentration increase due to a rapid Ca2+ release from intracellular stores and a transmembrane Ca2+ influx, mainly through L-type Ca2+ channels. Compelling evidences have demonstrated that Ca2+ might also enter through other cationic channels such as Store-Operated Ca2+ Channels (SOCCs, involved in several physiological functions and pathological conditions. The opening of SOCCs is regulated by the filling state of the intracellular Ca2+ store, the sarcoplasmic reticulum, which communicates to the plasma membrane channels through the Stromal Interaction Molecule 1/2 (STIM1/2 protein. In muscle cells, SOCCs can be mainly non-selective cation channels formed by Orai1 and other members of the Transient Receptor Potential-Canonical (TRPC channels family, as well as highly selective Ca2+ Release-Activated Ca2+ (CRAC channels, formed exclusively by subunits of Orai proteins likely organized in macromolecular complexes. This review summarizes the current knowledge of the complex role of Store Operated Calcium Entry (SOCE pathways and related proteins in the function of cardiac, skeletal, and vascular smooth muscle cells.

Arginase strongly impairs neuronal nitric oxide-mediated airway smooth muscle relaxation in allergic asthma

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Zaagsma Johan

2006-01-01

Full Text Available Abstract Background Using guinea pig tracheal preparations, we have recently shown that endogenous arginase activity attenuates inhibitory nonadrenergic noncholinergic (iNANC nerve-mediated airway smooth muscle relaxation by reducing nitric oxide (NO production – due to competition with neuronal NO-synthase (nNOS for the common substrate, L-arginine. Furthermore, in a guinea pig model of allergic asthma, airway arginase activity is markedly increased after the early asthmatic reaction (EAR, leading to deficiency of agonist-induced, epithelium-derived NO and subsequent airway hyperreactivity. In this study, we investigated whether increased arginase activity after the EAR affects iNANC nerve-derived NO production and airway smooth muscle relaxation. Methods Electrical field stimulation (EFS; 150 mA, 4 ms, 4 s, 0.5 – 16 Hz-induced relaxation was measured in tracheal open-ring preparations precontracted to 30% with histamine in the presence of 1 μM atropine and 3 μM indomethacin. The contribution of NO to EFS-induced relaxation was assessed by the nonselective NOS inhibitor Nω-nitro-L-arginine (L-NNA, 100 μM, while the involvement of arginase activity in the regulation of EFS-induced NO production and relaxation was investigated by the effect of the specific arginase inhibitor Nω-hydroxy-nor-L-arginine (nor-NOHA, 10 μM. Furthermore, the role of substrate availability to nNOS was measured in the presence of exogenous L-arginine (5.0 mM. Results At 6 h after ovalbumin-challenge (after the EAR, EFS-induced relaxation (ranging from 3.2 ± 1.1% at 0.5 Hz to 58.5 ± 2.2% at 16 Hz was significantly decreased compared to unchallenged controls (7.1 ± 0.8% to 75.8 ± 0.7%; P P P Conclusion The results clearly demonstrate that increased arginase activity after the allergen-induced EAR contributes to a deficiency of iNANC nerve-derived NO and decreased airway smooth muscle relaxation, presumably via increased substrate competition with nNOS.

Molecular mechanisms of maternal vascular dysfunction in preeclampsia.

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Goulopoulou, Styliani; Davidge, Sandra T

2015-02-01

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

Orchidectomy Ameliorates the Vascular Hypertrophic Effect of A ...

African Journals Online (AJOL)

Dr Olaleye Samuel

testosterone replacement (TR) (10mg/kg sustanon 250® i.m) once in 3 weeks. They were either placed ... hypertrophic effect of a HSD by reducing vascular smooth muscle proliferation and ..... NADPH oxidase plays a role in beta-tissue growth.

Deficiency of superoxide dismutase promotes cerebral vascular hypertrophy and vascular dysfunction in hyperhomocysteinemia.

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Sanjana Dayal

Full Text Available There is an emerging consensus that hyperhomocysteinemia is an independent risk factor for cerebral vascular disease and that homocysteine-lowering therapy protects from ischemic stroke. However, the mechanisms by which hyperhomocysteinemia produces abnormalities of cerebral vascular structure and function remain largely undefined. Our objective in this study was to define the mechanistic role of superoxide in hyperhomocysteinemia-induced cerebral vascular dysfunction and hypertrophy. Unlike previous studies, our experimental design included a genetic approach to alter superoxide levels by using superoxide dismutase 1 (SOD1-deficient mice fed a high methionine/low folate diet to produce hyperhomocysteinemia. In wild-type mice, the hyperhomocysteinemic diet caused elevated superoxide levels and impaired responses to endothelium-dependent vasodilators in cerebral arterioles, and SOD1 deficiency compounded the severity of these effects. The cross-sectional area of the pial arteriolar wall was markedly increased in mice with SOD1 deficiency, and the hyperhomocysteinemic diet sensitized SOD1-deficient mice to this hypertrophic effect. Analysis of individual components of the vascular wall demonstrated a significant increase in the content of smooth muscle and elastin. We conclude that superoxide is a key driver of both cerebral vascular hypertrophy and vasomotor dysfunction in this model of dietary hyperhomocysteinemia. These findings provide insight into the mechanisms by which hyperhomocysteinemia promotes cerebral vascular disease and ischemic stroke.

PPARα-Independent Arterial Smooth Muscle Relaxant Effects of PPARα Agonists

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Neerupma Silswal

2012-01-01

Full Text Available We sought to determine direct vascular effects of peroxisome proliferator-activated receptor alpha (PPARα agonists using isolated mouse aortas and middle cerebral arteries (MCAs. The PPARα agonists GW7647, WY14643, and gemfibrozil acutely relaxed aortas held under isometric tension and dilated pressurized MCAs with the following order of potency: GW7647≫WY14643>gemfibrozil. Responses were endothelium-independent, and the use of PPARα deficient mice demonstrated that responses were also PPARα-independent. Pretreating arteries with high extracellular K+ attenuated PPARα agonist-mediated relaxations in the aorta, but not in the MCA. In the aorta, the ATP sensitive potassium (KATP channel blocker glibenclamide also impaired relaxations whereas the other K+ channel inhibitors, 4-aminopyridine and Iberiotoxin, had no effect. In aortas, GW7647 and WY14643 elevated cGMP levels by stimulating soluble guanylyl cyclase (sGC, and inhibition of sGC with ODQ blunted relaxations to PPARα agonists. In the MCA, dilations were inhibited by the protein kinase C (PKC activator, phorbol 12,13-dibutyrate, and also by ODQ. Our results demonstrated acute, nonreceptor-mediated relaxant effects of PPARα agonists on smooth muscle of mouse arteries. Responses to PPARα agonists in the aorta involved KATP channels and sGC, whereas in the MCA the PKC and sGC pathways also appeared to contribute to the response.

Divergent effects of 17-β-estradiol on human vascular smooth muscle and endothelial cell function diminishes TNF-α-induced neointima formation

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Nintasen, Rungrat; Riches, Kirsten; Mughal, Romana S.; Viriyavejakul, Parnpen; Chaisri, Urai; Maneerat, Yaowapa; Turner, Neil A.; Porter, Karen E.

2012-01-01

Highlights: ► TNF-α augments neointimal hyperplasia in human saphenous vein. ► TNF-α induces detrimental effects on endothelial and smooth muscle cell function. ► Estradiol exerts modulatory effects on TNF-induced vascular cell functions. ► The modulatory effects of estradiol are discriminatory and cell-type specific. -- Abstract: Coronary heart disease (CHD) is a condition characterized by increased levels of proinflammatory cytokines, including tumor necrosis factor-α (TNF-α). TNF-α can induce vascular endothelial cell (EC) and smooth muscle cell (SMC) dysfunction, central events in development of neointimal lesions. The reduced incidence of CHD in young women is believed to be due to the protective effects of estradiol (E2). We therefore investigated the effects of TNF-α on human neointima formation and SMC/EC functions and any modulatory effects of E2. Saphenous vein (SV) segments were cultured in the presence of TNF-α (10 ng/ml), E2 (2.5 nM) or both in combination. Neointimal thickening was augmented by incubation with TNF-α, an effect that was abolished by co-culture with E2. TNF-α increased SV–SMC proliferation in a concentration-dependent manner that was optimal at 10 ng/ml (1.5-fold increase), and abolished by E2 at all concentrations studied (1–50 nM). Surprisingly, E2 itself at low concentrations (1 and 5 nM) stimulated SV–SMC proliferation to a level comparable to that of TNF-α alone. SV–EC migration was significantly impaired by TNF-α (42% of control), and co-culture with E2 partially restored the ability of SV–EC to migrate and repair the wound. In contrast, TNF-α increased SV–SMC migration by 1.7-fold, an effect that was completely reversed by co-incubation with E2. Finally, TNF-α potently induced ICAM-1 and VCAM-1 expression in both SV–EC and SV–SMC. However there was no modulation by E2 in either cell-type. In conclusion, TNF-α induced SV neointima formation, increased SMC proliferation and migration, impaired

Differential Cellular and Molecular Effects of Butyrate and Trichostatin A on Vascular Smooth Muscle Cells

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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.

Extracellular acidosis and very low [Na+ ] inhibit NBCn1- and NHE1-mediated net acid extrusion from mouse vascular smooth muscle cells.

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Bonde, L; Boedtkjer, E

2017-10-01

The electroneutral Na + , HCO3- cotransporter NBCn1 and Na + /H + exchanger NHE1 regulate acid-base balance in vascular smooth muscle cells (VSMCs) and modify artery function and structure. Pathological conditions - notably ischaemia - can dramatically perturb intracellular (i) and extracellular (o) pH and [Na + ]. We examined effects of low [Na + ] o and pH o on NBCn1 and NHE1 activity in VSMCs of small arteries. We measured pH i by 2',7'-bis-(2-carboxyethyl)-5-(and-6)-carboxyfluorescein-based fluorescence microscopy of mouse mesenteric arteries and induced intracellular acidification by NH4+ prepulse technique. NBCn1 activity - defined as Na + -dependent, amiloride-insensitive net base uptake with CO 2 /HCO3- present - was inhibited equally when pH o decreased from 7.4 (22 mm HCO3-/5% CO 2 ) by metabolic (pH o 7.1/11 mm HCO3-: 22 ± 8%; pH o 6.8/5.5 mm HCO3-: 61 ± 7%) or respiratory (pH o 7.1/10% CO 2 : 35 ± 11%; pH o 6.8/20% CO 2 : 56 ± 7%) acidosis. Extracellular acidosis more prominently inhibited NHE1 activity - defined as Na + -dependent net acid extrusion without CO 2 /HCO3- present - at both pH o 7.1 (45 ± 9%) and 6.8 (85 ± 5%). Independently of pH o , lowering [Na + ] o from 140 to 70 mm reduced NBCn1 and NHE1 activity respiratory (ΔpH i /ΔpH o  = 71 ± 4%) than metabolic (ΔpH i /ΔpH o  = 30 ± 7%) acidosis. Extracellular acidification inhibits NBCn1 and NHE1 activity in VSMCs. NBCn1 is equivalently inhibited when pCO 2 is raised or [HCO3-] o decreased. Lowering [Na + ] o inhibits NBCn1 and NHE1 markedly only below the typical physiological and pathophysiological range. We propose that inhibition of Na + -dependent net acid extrusion at low pH o protects against cellular Na + overload at the cost of intracellular acidification. © 2017 Scandinavian Physiological Society. Published by John Wiley & Sons Ltd.

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

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Khalil, Raouf A

2013-12-15

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

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

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Olivier Espitia

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

Vardenafil inhibiting parasympathetic function of tracheal smooth muscle.

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Lee, Fei-Peng; Chao, Pin-Zhir; Wang, Hsing-Won

2018-07-01

Levitra, a phosphodiesterase-5 (PDE5) inhibitor, is the trade name of vardenafil. Nowadays, it is applied to treatment of erectile dysfunction. PDE5 inhibitors are employed to induce dilatation of the vascular smooth muscle. The effect of Levitra on impotency is well known; however, its effect on the tracheal smooth muscle has rarely been explored. When administered for sexual symptoms via oral intake or inhalation, Levitra might affect the trachea. This study assessed the effects of Levitra on isolated rat tracheal smooth muscle by examining its effect on resting tension of tracheal smooth muscle, contraction caused by 10 -6  M methacholine as a parasympathetic mimetic, and electrically induced tracheal smooth muscle contractions. The results showed that adding methacholine to the incubation medium caused the trachea to contract in a dose-dependent manner. Addition of Levitra at doses of 10 -5  M or above elicited a significant relaxation response to 10 -6  M methacholine-induced contraction. Levitra could inhibit electrical field stimulation-induced spike contraction. It alone had minimal effect on the basal tension of the trachea as the concentration increased. High concentrations of Levitra could inhibit parasympathetic function of the trachea. Levitra when administered via oral intake might reduce asthma attacks in impotent patients because it might inhibit parasympathetic function and reduce methacholine-induced contraction of the tracheal smooth muscle. Copyright © 2018. Published by Elsevier Taiwan LLC.

Artery Tertiary Lymphoid Organs Control Aorta Immunity and Protect against Atherosclerosis via Vascular Smooth Muscle Cell Lymphotoxin β Receptors

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Hu, Desheng; Mohanta, Sarajo K.; Yin, Changjun; Peng, Li; Ma, Zhe; Srikakulapu, Prasad; Grassia, Gianluca; MacRitchie, Neil; Dever, Gary; Gordon, Peter; Burton, Francis L.; Ialenti, Armando; Sabir, Suleman R.; McInnes, Iain B.; Brewer, James M.; Garside, Paul; Weber, Christian; Lehmann, Thomas; Teupser, Daniel; Habenicht, Livia; Beer, Michael; Grabner, Rolf; Maffia, Pasquale; Weih, Falk; Habenicht, Andreas J.R.

2015-01-01

Summary Tertiary lymphoid organs (TLOs) emerge during nonresolving peripheral inflammation, but their impact on disease progression remains unknown. We have found in aged Apoe−/− mice that artery TLOs (ATLOs) controlled highly territorialized aorta T cell responses. ATLOs promoted T cell recruitment, primed CD4+ T cells, generated CD4+, CD8+, T regulatory (Treg) effector and central memory cells, converted naive CD4+ T cells into induced Treg cells, and presented antigen by an unusual set of dendritic cells and B cells. Meanwhile, vascular smooth muscle cell lymphotoxin β receptors (VSMC-LTβRs) protected against atherosclerosis by maintaining structure, cellularity, and size of ATLOs though VSMC-LTβRs did not affect secondary lymphoid organs: Atherosclerosis was markedly exacerbated in Apoe−/−Ltbr−/− and to a similar extent in aged Apoe−/−Ltbrfl/flTagln-cre mice. These data support the conclusion that the immune system employs ATLOs to organize aorta T cell homeostasis during aging and that VSMC-LTβRs participate in atherosclerosis protection via ATLOs. PMID:26084025

Zinc regulates Nox1 expression through a NF-κB and mitochondrial ROS dependent mechanism to induce senescence of vascular smooth muscle cells.

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Salazar, G; Huang, J; Feresin, R G; Zhao, Y; Griendling, K K

2017-07-01

The role of oxidative stress and inflammation in the development and progression of cardiovascular diseases (CVD) is well established. Increases in oxidative stress can further exacerbate the inflammatory response and lead to cellular senescence. We previously reported that angiotensin II (Ang II) and zinc increase reactive oxygen species (ROS) and cause senescence of vascular smooth muscle cells (VSMCs) and that senescence induced by Ang II is a zinc-dependent process. Zinc stimulated NADPH oxidase (Nox) activity; however, the role of Nox isoforms in zinc effects was not determined. Here, we show that downregulation of Nox1, but not Nox4, by siRNA prevented both Ang II- and zinc-induced senescence in VSMCs. On the other hand, overexpression of Nox1 induced senescence, which was associated with reduced proliferation, reduced expression of telomerase and increased DNA damage. Zinc increased Nox1 protein expression, which was inhibited by chelation of zinc with TPEN and by overexpression of the zinc exporters ZnT3 and ZnT10. These transporters work to reduce cytosolic zinc, suggesting that increased cytosolic zinc mediates Nox1 upregulation. Other metals including copper, iron, cobalt and manganese failed to upregulate Nox1, suggesting that this pathway is zinc specific. Nox1 upregulation was inhibited by actinomycin D (ACD), an inhibitor of transcription, by inhibition of NF-κB, a known Nox1 transcriptional regulator and by N-acetyl cysteine (NAC) and MitoTEMPO, suggesting that NF-κB and mitochondrial ROS mediate zinc effects. Supporting this idea, we found that zinc increased NF-κB activation in the cytosol, stimulated the translocation of the p65 subunit to the nucleus, and that zinc accumulated in mitochondria increasing mitochondrial ROS, measured using MitoSox. Further, zinc-induced senescence was reduced by inhibition of NF-κB or reduction of mitochondrial ROS with MitoTEMPO. NF-κB activity was also reduced by MitoTEMPO, suggesting that mitochondrial ROS

Generation and Characterization of Vascular Smooth Muscle Cell Lines Derived from a Patient with a Bicuspid Aortic Valve

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Pamela Lazar-Karsten

2016-04-01

Full Text Available Thoracic aortic dilation is the most common malformation of the proximal aorta and is responsible for 1%–2% of all deaths in industrialized countries. In approximately 50% of patients with a bicuspid aortic valve (BAV, dilation of any or all segments of the aorta occurs. BAV patients with aortic dilation show an increased incidence of cultured vascular smooth muscle cell (VSMC loss. In this study, VSMC, isolated from the ascending aorta of BAV, was treated with Simian virus 40 to generate a BAV-originated VSMC cell line. To exclude any genomic DNA or cross-contamination, highly polymorphic short tandem repeats of the cells were profiled. The cells were then characterized using flow cytometry and karyotyping. The WG-59 cell line created is the first reported VSMC cell line isolated from a BAV patient. Using an RT2 Profiler PCR Array, genes within the TGFβ/BMP family that are dependent on losartan treatment were identified. Endoglin was found to be among the regulated genes and was downregulated in WG-59 cells following treatment with different losartan concentrations, when compared to untreated WG-59 cells.

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

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Yu-Ying Chen

2013-01-01

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

Genipin inhibits TNF-α-induced vascular smooth muscle cell proliferation and migration via induction of HO-1.

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Fengrong Jiang

Full Text Available Vascular smooth muscle cell (VSMC proliferation and migration triggered by inflammatory stimuli contributes importantly to the pathogenesis of atherosclerosis and restenosis. On the other hand, genipin, an aglycon of geniposide, exhibits diverse pharmacological functions such as antitumor and anti-inflammatory effects. The protective effects of genipin on the cardiovascular system have also been reported. However, the molecular mechanism involved remains unknown. This study aimed to elucidate the precise function of genipin in VSMCs, focusing particularly on the role of heme oxygenase-1 (HO-1, a potent anti-inflammatory enzyme. We found that pretreatment of genipin induced HO-1 mRNA and protein levels, as well as its activity in VSMCs. Genipin inhibited TNF-α-induced VSMC proliferation and migration in a dose-dependent manner. At the molecular level, genipin prevented ERK/MAPK and Akt phosphorylation while left p38 MAPK and JNK unchanged. Genipin also blocked the increase of ROS generation induced by TNF-α. More importantly, the specific HO-1 siRNA partially abolished the beneficial effects of genipin on VSMCs. These results suggest that genipin may serve as a novel drug in the treatment of these pathologies by inducing HO-1 expression/activity and subsequently decreasing VSMC proliferation and migration.

Cyclic Mechanical Stretch Up-regulates Hepatoma-Derived Growth Factor Expression in Cultured Rat Aortic Smooth Muscle Cells.

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Kao, Ying-Hsien; Chen, Po-Han; Sun, Cheuk-Kwan; Chang, Yo-Chen; Lin, Yu-Chun; Tsai, Ming-Shian; Lee, Po-Huang; Cheng, Cheng-I

2018-02-21

Hepatoma-derived growth factor (HDGF) is a potent mitogen for vascular smooth muscle cells (SMCs) during embryogenesis and injury repair of vessel walls. Whether mechanical stimuli modulate HDGF expression remains unknown. This study aimed at investigating whether cyclic mechanical stretch plays a regulatory role in HDGF expression and regenerative cytokine production in aortic SMCs. A SMC cell line was grown on a silicone-based elastomer chamber with extracellular matrix coatings (either type I collagen or fibronectin) and received cyclic and uni-axial mechanical stretches with 10% deformation at frequency 1 Hz. Morphological observation showed that fibronectin coating provided better cell adhesion and spreading and that consecutive 6 hours of cyclic mechanical stretch remarkably induced reorientation and realignment of SMCs. Western blotting detection demonstrated that continuous mechanical stimuli elicited up-regulation of HDGF and PCNA, a cell proliferative marker. Signal kinetic profiling study indicated that cyclic mechanical stretch induced signaling activity in RhoA/ROCK and PI3K/Akt cascades. Kinase inhibition study further showed that blockade of PI3K activity suppressed the stretch-induced TNF-a, whereas RhoA/ROCK inhibition significantly blunted the IL-6 production and HDGF over-expression. Moreover, siRNA-mediated HDGF gene silencing significantly suppressed constitutive expression of IL-6, but not TNF-α, in SMCs. These findings support the role of HDGF in maintaining vascular expression of IL-6, which has been regarded a crucial regenerative factor for acute vascular injury. In conclusion, cyclic mechanical stretch may maintain constitutive expression of HDGF in vascular walls and be regarded an important biophysical regulator in vascular regeneration. ©2018 The Author(s).

Smooth Muscle Specific Overexpression of p22phox Potentiates Carotid Artery Wall Thickening in Response to Injury

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Michael R. Manogue

2015-01-01

Full Text Available We hypothesized that transgenic mice overexpressing the p22phox subunit of the NADPH oxidase selectively in smooth muscle (Tgp22smc would exhibit an exacerbated response to transluminal carotid injury compared to wild-type mice. To examine the role of reactive oxygen species (ROS as a mediator of vascular injury, the injury response was quantified by measuring wall thickness (WT and cross-sectional wall area (CSWA of the injured and noninjured arteries in both Tgp22smc and wild-type animals at days 3, 7, and 14 after injury. Akt, p38 MAPK, and Src activation were evaluated at the same time points using Western blotting. WT and CSWA following injury were significantly greater in Tgp22smc mice at both 7 and 14 days after injury while noninjured contralateral carotids were similar between groups. Apocynin treatment attenuated the injury response in both groups and rendered the response similar between Tgp22smc mice and wild-type mice. Following injury, carotid arteries from Tgp22smc mice demonstrated elevated activation of Akt at day 3, while p38 MAPK and Src activation was elevated at day 7 compared to wild-type mice. Both increased activation and temporal regulation of these signaling pathways may contribute to enhanced vascular growth in response to injury in this transgenic model of elevated vascular ROS.

Vasohibin inhibits angiogenic sprouting in vitro and supports vascular maturation processes in vivo

International Nuclear Information System (INIS)

Kern, Johann; Steurer, Michael; Gastl, Günther; Gunsilius, Eberhard; Untergasser, Gerold

2009-01-01

The murine homologue of human vasohibin (mVASH1), a putative antiangiogenic protein, was investigated for its effects on in vitro and in vivo angiogenesis. Cell growth and migration were analyzed in murine fibroblasts, smooth muscle cells and endothelial cells. Angiogenic sprouting was studied in human umbilical vein endothelial cells (HUVECs) in the spheroid sprouting assay. In vivo effects on blood vessel formation were investigated in the chorioallantoic membrane (CAM) assay and in the C57BL/6 melanoma xenograft model. Purified murine and human VASH1 protein induced apoptosis of murine fibroblasts in vitro, but not of vascular aortic smooth muscle cells (AoSMC) or endothelial cells. Adenoviral overexpression of murine and human VASH1 inhibited capillary sprouting of HUVECs in the spheroid assay. Administration of recombinant murine and human VASH1 inhibited growth of large vessels in the CAM assay and promoted the formation of a dense, fine vascular network. Murine VASH1-overexpressing B16F10 melanomas displayed a reduction in large vessels and vascular area. Moreover, tumors showed more microvessels that stained positive for the mural cell markers α-smooth muscle cell actin (ASMA) and proteoglycan (NG2). Our data imply that murine VASH1 causes angiogenic remodelling by inhibiting angiogenic sprouting and large vessel growth, thereby supporting the formation of a vascular bed consisting predominantly of mature microvessels

The zinc transporter ZIP12 regulates the pulmonary vascular response to chronic hypoxia.

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Zhao, Lan; Oliver, Eduardo; Maratou, Klio; Atanur, Santosh S; Dubois, Olivier D; Cotroneo, Emanuele; Chen, Chien-Nien; Wang, Lei; Arce, Cristina; Chabosseau, Pauline L; Ponsa-Cobas, Joan; Frid, Maria G; Moyon, Benjamin; Webster, Zoe; Aldashev, Almaz; Ferrer, Jorge; Rutter, Guy A; Stenmark, Kurt R; Aitman, Timothy J; Wilkins, Martin R

2015-08-20

The typical response of the adult mammalian pulmonary circulation to a low oxygen environment is vasoconstriction and structural remodelling of pulmonary arterioles, leading to chronic elevation of pulmonary artery pressure (pulmonary hypertension) and right ventricular hypertrophy. Some mammals, however, exhibit genetic resistance to hypoxia-induced pulmonary hypertension. We used a congenic breeding program and comparative genomics to exploit this variation in the rat and identified the gene Slc39a12 as a major regulator of hypoxia-induced pulmonary vascular remodelling. Slc39a12 encodes the zinc transporter ZIP12. Here we report that ZIP12 expression is increased in many cell types, including endothelial, smooth muscle and interstitial cells, in the remodelled pulmonary arterioles of rats, cows and humans susceptible to hypoxia-induced pulmonary hypertension. We show that ZIP12 expression in pulmonary vascular smooth muscle cells is hypoxia dependent and that targeted inhibition of ZIP12 inhibits the rise in intracellular labile zinc in hypoxia-exposed pulmonary vascular smooth muscle cells and their proliferation in culture. We demonstrate that genetic disruption of ZIP12 expression attenuates the development of pulmonary hypertension in rats housed in a hypoxic atmosphere. This new and unexpected insight into the fundamental role of a zinc transporter in mammalian pulmonary vascular homeostasis suggests a new drug target for the pharmacological management of pulmonary hypertension.

Upregulation of vascular endothelial growth factor receptor-1 contributes to sevoflurane preconditioning–mediated cardioprotection

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Qian B

2018-04-01

Full Text Available Bin Qian,1 Yang Yang,2 Yusheng Yao,3 Yanling Liao,3 Ying Lin3 1Department of Anesthesiology, People’s Hospital Affiliated to Fujian University of Traditional Chinese Medicine, Fuzhou, Fujian, China; 2Department of Anesthesiology, West China Hospital, Sichuan University, Chengdu, Sichuan, China; 3Department of Anesthesiology, The Shengli Clinical Medical College, Fujian Medical University, Fuzhou, Fujian, China Purpose: Sevoflurane preconditioning (SPC can provide myocardial protective effects similar to ischemic preconditioning. However, the exact mechanism of SPC remains unclear. Previous studies indicate that vascular endothelial growth factor receptor 1 (VEGFR-1 is involved in ischemic preconditioning-mediated cardioprotection. This study was designed to determine the significance of VEGFR-1 signaling in SPC-mediated cardioprotection.Materials and methods: Myocardial ischemia–reperfusion (I/R rat model was established using the Langendorff isolated heart perfusion apparatus. Additionally, after 15 min of baseline equilibration, the isolated hearts were pretreated with 2.5% sevoflurane, 2.5% sevoflurane+MF1 10 µmol/L, or 2.5% sevoflurane+placental growth factor 10 µmol/L, and then subjected to 30 min of global ischemia and 120 min of reperfusion. The changes in hemodynamic parameters, myocardial infarct size, and the levels of creatine kinase-MB, lactate dehydrogenase, cardiac troponin-I, tumor necrosis factor-α, and interleukin 6 in the myocardium were evaluated.Results: Compared to the I/R group, pretreatment with 2.5% sevoflurane significantly improved the cardiac function, limited myocardial infarct size, reduced cardiac enzyme release, upregulated VEGFR-1 expression, and decreased inflammation. In addition, the selective VEGFR-1 agonist, placental growth factor, did not enhance the cardioprotection and anti-inflammation effects of sevoflurane, while the specific VEGFR-1 inhibitor, MF1, completely reversed these effects

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

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

2016-01-01

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

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

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Gemma Chiva-Blanch

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

ASIC PROTEINS REGULATE SMOOTH MUSCLE CELL MIGRATION

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Grifoni, Samira C.; Jernigan, Nikki L.; Hamilton, Gina; Drummond, Heather A.

2007-01-01

The purpose of the present study was to investigate Acid Sensing Ion Channel (ASIC) protein expression and importance in cellular migration. We recently demonstrated Epithelial Na+ Channel (ENaC) proteins are required for vascular smooth muscle cell (VSMC) migration, however the role of the closely related ASIC proteins has not been addressed. We used RT-PCR and immunolabeling to determine expression of ASIC1, ASIC2, ASIC3 and ASIC4 in A10 cells. We used small interference RNA to silence indi...

Alcohol and Cardiovascular Disease—Modulation of Vascular Cell Function

Directory of Open Access Journals (Sweden)

Paul A. Cahill

2012-04-01

Full Text Available Alcohol is a commonly used drug worldwide. Epidemiological studies have identified alcohol consumption as a factor that may either positively or negatively influence many diseases including cardiovascular disease, certain cancers and dementia. Often there seems to be a differential effect of various drinking patterns, with frequent moderate consumption of alcohol being salutary and binge drinking or chronic abuse being deleterious to one’s health. A better understanding of the cellular and molecular mechanisms mediating the many effects of alcohol consumption is beginning to emerge, as well as a clearer picture as to whether these effects are due to the direct actions of alcohol itself, or caused in part by its metabolites, e.g., acetaldehyde, or by incidental components present in the alcoholic beverage (e.g., polyphenols in red wine. This review will discuss evidence to date as to how alcohol (ethanol might affect atherosclerosis that underlies cardiovascular and cerebrovascular disease, and the putative mechanisms involved, focusing on vascular endothelial and smooth muscle cell effects.

[Experimental study of angiography using vascular interventional robot-2(VIR-2)].

Science.gov (United States)

Tian, Zeng-min; Lu, Wang-sheng; Liu, Da; Wang, Da-ming; Guo, Shu-xiang; Xu, Wu-yi; Jia, Bo; Zhao, De-peng; Liu, Bo; Gao, Bao-feng

2012-06-01

To verify the feasibility and safety of new vascular interventional robot system used in vascular interventional procedures. Vascular interventional robot type-2 (VIR-2) included master-slave parts of body propulsion system, image navigation systems and force feedback system, the catheter movement could achieve under automatic control and navigation, force feedback was integrated real-time, followed by in vitro pre-test in vascular model and cerebral angiography in dog. Surgeon controlled vascular interventional robot remotely, the catheter was inserted into the intended target, the catheter positioning error and the operation time would be evaluated. In vitro pre-test and animal experiment went well; the catheter can enter any branch of vascular. Catheter positioning error was less than 1 mm. The angiography operation in animal was carried out smoothly without complication; the success rate of the operation was 100% and the entire experiment took 26 and 30 minutes, efficiency was slightly improved compared with the VIR-1, and the time what staff exposed to the DSA machine was 0 minute. The resistance of force sensor can be displayed to the operator to provide a security guarantee for the operation. No surgical complications. VIR-2 is safe and feasible, and can achieve the catheter remote operation and angiography; the master-slave system meets the characteristics of traditional procedure. The three-dimensional image can guide the operation more smoothly; force feedback device provides remote real-time haptic information to provide security for the operation.

Prolonged hypoxia modulates platelet activating factor receptor-mediated responses by fetal ovine pulmonary vascular smooth muscle cells.

Science.gov (United States)

Renteria, Lissette S; Raj, J Usha; Ibe, Basil O

2010-12-01

Hypoxia augments PAF receptor (PAFr) binding and PAFr protein expression in venous SMC (SMC-PV). We compared effect of acute and prolonged hypoxia (pO(2)<40 torr) on PAFr-mediated responses in arterial SMC (SMC-PA) and SMC-PV. Cells were studied for 30 min (acute) or for 48 h (prolonged) hypoxia and compared to normoxic (pO(2) ~100 torr) conditions. PAF binding was quantified in fmol/10(6) cells (mean ± SEM). PAF binding in normoxia were SMC-PA, 5.2 ± 0.2 and in SMC-PV, 19.3 ± 1.1; values in acute hypoxia were SMC-PA, 7.7 ± 0.4 and in SMC-PV, 27.8 ± 1.7. Prolonged hypoxia produced 6-fold increase in binding in SMC-PA, but only 2-fold increase in SMC-PV, but binding in SMC-PV was still higher. Acute hypoxia augmented inositol phosphate release by 50% and 40% in SMC-PA and SMC-PV, respectively. During normoxia, PAFr mRNA expression by both cell types was similar, but expression in hypoxia by SMC-PA was greater. In SMC-PA, hypoxia and PAF augmented intracellular calcium flux. Re-exposure of cells to 30 min normoxia after 48 h hypoxia decreased binding by 45-60%, suggesting immediate down-regulation of hypoxia-induced PAFr-mediated effects. We speculate that re-oxygenation immediately reverses hypoxia effect probably due to oxygen tension-dependent reversibility of PAFr activation and suggest that exposure of the neonate to prolonged state of hypoxia will vilify oxygen exchange capacity of the neonatal lungs. Copyright © 2010 Elsevier Inc. All rights reserved.

Expression pattern and function of tyrosine receptor kinase B isoforms in rat mesenteric arterial smooth muscle cells

International Nuclear Information System (INIS)

Otani, Kosuke; Okada, Muneyoshi; Yamawaki, Hideyuki

2015-01-01

Tyrosine receptor kinaseB (TrkB) is a high affinity receptor for brain-derived neurotrophic factor (BDNF). TrkB isoforms involve full length TrkB (TrkB FL) and truncated TrkB type1 (TrkB T1) and type 2 (TrkB T2) in rats. The aim of present study was to explore their expression pattern and function in mesenteric arterial smooth muscle cells (MASMCs). The expression of TrkB isoform protein and mRNA was examined by Western blotting, immunofluorescence and quantitative RT-PCR analyses. Cell proliferation was measured by a bromodeoxyuridine (BrdU) incorporation assay. Cell migration was measured by a Boyden chamber assay. Cell morphology was observed with a phase-contrast microscope. Protein and mRNA expression of BDNF and TrkB isoforms was confirmed in MASMCs. Expression level of TrkB FL was less, while that of TrkB T1 was the highest in MASMCs. Although BDNF increased phosphorylation of ERK, it had no influence on migration and proliferation of MASMCs. TrkB T1 gene knockdown by a RNA interference induced morphological changes and reduced expression level of α-smooth muscle actin (α-SMA) in MASMCs. Similar morphological changes and reduced α-SMA expression were induced in MASMCs by a Rho kinase inhibitor, Y-27632. In conclusion, we for the first time demonstrate that TrkB T1 expressed highly in MASMCs contributes to maintain normal cell morphology possibly via regulation of Rho activity. This study firstly defined expression level of TrkB isoforms and partly revealed their functions in peripheral vascular cells. - Highlights: • BDNF-TrkB axis mediates neurogenesis, growth, differentiation and survival. • Expression pattern and function of TrkB in vascular smooth muscle remain unclear. • Expression of TrkB FL is low, while that of TrkB T1 is the highest. • TrkB T1 contributes to maintain normal morphology possibly via activating Rho.

Expression pattern and function of tyrosine receptor kinase B isoforms in rat mesenteric arterial smooth muscle cells

Energy Technology Data Exchange (ETDEWEB)

Otani, Kosuke; Okada, Muneyoshi; Yamawaki, Hideyuki, E-mail: yamawaki@vmas.kitasato-u.ac.jp

2015-11-27

Tyrosine receptor kinaseB (TrkB) is a high affinity receptor for brain-derived neurotrophic factor (BDNF). TrkB isoforms involve full length TrkB (TrkB FL) and truncated TrkB type1 (TrkB T1) and type 2 (TrkB T2) in rats. The aim of present study was to explore their expression pattern and function in mesenteric arterial smooth muscle cells (MASMCs). The expression of TrkB isoform protein and mRNA was examined by Western blotting, immunofluorescence and quantitative RT-PCR analyses. Cell proliferation was measured by a bromodeoxyuridine (BrdU) incorporation assay. Cell migration was measured by a Boyden chamber assay. Cell morphology was observed with a phase-contrast microscope. Protein and mRNA expression of BDNF and TrkB isoforms was confirmed in MASMCs. Expression level of TrkB FL was less, while that of TrkB T1 was the highest in MASMCs. Although BDNF increased phosphorylation of ERK, it had no influence on migration and proliferation of MASMCs. TrkB T1 gene knockdown by a RNA interference induced morphological changes and reduced expression level of α-smooth muscle actin (α-SMA) in MASMCs. Similar morphological changes and reduced α-SMA expression were induced in MASMCs by a Rho kinase inhibitor, Y-27632. In conclusion, we for the first time demonstrate that TrkB T1 expressed highly in MASMCs contributes to maintain normal cell morphology possibly via regulation of Rho activity. This study firstly defined expression level of TrkB isoforms and partly revealed their functions in peripheral vascular cells. - Highlights: • BDNF-TrkB axis mediates neurogenesis, growth, differentiation and survival. • Expression pattern and function of TrkB in vascular smooth muscle remain unclear. • Expression of TrkB FL is low, while that of TrkB T1 is the highest. • TrkB T1 contributes to maintain normal morphology possibly via activating Rho.

Design, synthesis and biological evaluation of novel ring-opened cromakalim analogues with relaxant effects on vascular and respiratory smooth muscles and as stimulators of elastin synthesis.

Science.gov (United States)

Bouhedja, Mourad; Peres, Basile; Fhayli, Wassim; Ghandour, Zeinab; Boumendjel, Ahcène; Faury, Gilles; Khelili, Smail

2018-01-20

Two new series of ring-opened analogues of cromakalim bearing sulfonylurea moieties (series A: with N-unmethylated sulfonylureas, series B: with N-methylated sulfonylureas) were synthesized and tested as relaxants of vascular and respiratory smooth muscles (rat aorta and trachea, respectively). Ex vivo biological evaluations indicated that the most active compounds, belonging to series B, displayed a marked vasorelaxant activity on endothelium-intact aortic rings and the trachea. A majority of series B compounds exhibited a higher vasorelaxant activity (EC 50  stronger relaxant effects on the trachea than the reference compound cromakalim (EC 50  = 124 μM), in particular compounds B4, B7 and B16 (EC 50   57 μM for all, and EC 50  > 200 μM for a majority of them), but some of them showed an interesting relaxing effect on trachea (i.e. A15 and A33, EC 50  = 30 μM). The most potent compounds of both series, i.e. A15, A33 and B16, tested on aortic rings in the presence of glibenclamide or 80 mM KCl, suggested that they acted as voltage-gated Ca 2+ channel blockers, like verapamil, instead of being ATP-potassium channel activators, as is cromakalim, the parent molecule. Further investigations on cultured vascular smooth muscle cells showed a strong stimulating effect on elastin synthesis, especially compound B16, which was more active at 20 μM than diazoxide, a reference ATP-sensitive potassium channel activator. Taken together, our results show that the N-methylation of the sulfonylurea moieties of ring-opened cromakalim analogues led to new compounds blocking calcium-gated channels, which had a major impact on the arterial and tracheal activities as well as selectivity. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Intermittent injections of osteocalcin reverse autophagic dysfunction and endoplasmic reticulum stress resulting from diet-induced obesity in the vascular tissue via the NFκB-p65-dependent mechanism.

Science.gov (United States)

Zhou, Bo; Li, Huixia; Liu, Jiali; Xu, Lin; Zang, Weijin; Wu, Shufang; Sun, Hongzhi

2013-06-15

The osteoblast-specific secreted molecule osteocalcin behaves as a hormone-regulating glucose and lipid metabolism, but the role of osteocalcin in cardiovascular disease (CVD) is not fully understood. In the present study, we investigated the effect of osteocalcin on autophagy and endoplasmic reticulum (ER) stress secondary to diet-induced obesity in the vascular tissue of mice and in vascular cell models and clarified the intracellular events responsible for osteocalcin-mediated effects. The evidences showed that intermittent injections of osteocalcin in mice fed the high-fat diet were associated with a reduced body weight gain, decreased blood glucose and improved insulin sensitivity compared with mice fed the high-fat diet receiving vehicle. Simultaneously, the administration of osteocalcin not only attenuated autophagy and ER stress but also rescued impaired insulin signaling in vascular tissues of mice fed a high-fat diet. Consistent with these results in vivo, the addition of osteocalcin reversed autophagy and ER stress and restored defective insulin sensitivity in vascular endothelial cells (VECs) and vascular smooth muscle cells (VSMCs) in the presence of tunicamycin or in knockout XBP-1 (a transcription factor which mediates ER stress response) cells or in Atg7(-/-) cells. The protective effects of osteocalcin were nullified by suppression of Akt, mammalian target of rapamycin (mTOR) or nuclear factor kappa B (NFκB), suggesting that osteocalcin inhibits autophagy, ER stress and improves insulin signaling in the vascular tissue and cells under insulin resistance in a NFκB-dependent manner, which may be a promising therapeutic strategies of cardiovascular dysfunction secondary to obesity.

Vascularized bone transplant chimerism mediated by vascular endothelial growth factor.

Science.gov (United States)

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

2015-01-01

Vascular endothelial growth factor (VEGF) induces angiogenesis and osteogenesis in bone allotransplants. We aim to determine whether bone remodeling in VEGF-treated bone allotransplants results from repopulation with circulation-derived autogenous cells or survival of allogenic transplant-derived cells. Vascularized femoral bone transplants were transplanted from female Dark Agouti rats (DA;RT1(a) ) to male Piebald Viral Glaxo (PVG;RT1(c) ). Arteriovenous bundle implantation and short-term immunosuppression were used to maintain cellular viability. VEGF was encapsulated in biodegradable microspheres and delivered intramedullary in the experimental group (n = 22). In the control group (n = 22), no VEGF was delivered. Rats were sacrificed at 4 or 18 weeks. Laser capture microdissection of bone remodeling areas was performed at the inner and outer cortex. Sex-mismatched genes were quantified with reverse transcription-polymerase chain reaction to determine the amount of male cells to total cells, defined as the relative expression ratio (rER). At 4 weeks, rER was significantly higher at the inner cortex in VEGF-treated transplants as compared to untreated transplants (0.622 ± 0.225 vs. 0.362 ± 0.081, P = 0.043). At 4 weeks, the outer cortex in the control group had a significantly higher rER (P = 0.038), whereas in the VEGF group, the inner cortex had a higher rER (P = 0.015). Over time, in the outer cortex the rER significantly increased to 0.634 ± 0.106 at 18 weeks in VEGF-treated rats (P = 0.049). At 18 weeks, the rER was >0.5 at all cortical areas in both groups. These in vivo findings suggest a chemotactic effect of intramedullary applied VEGF on recipient-derived bone and could imply that more rapid angiogenesis of vascularized allotransplants can be established with microencapsulated VEGF. © 2014 Wiley Periodicals, Inc.

Vascular smooth muscle cells in cultures on biofunctionalized cellulose-based scaffolds

Czech Academy of Sciences Publication Activity Database

Novotná, Katarína; Bačáková, Lucie; Lisá, Věra; Havelka, P.; Sopuch, T.; Klepetář, Jan

2009-01-01

Roč. 12, 89-91 (2009), s. 21-24 ISSN 1429-7248 R&D Projects: GA MŠk(CZ) 2B06173; GA MPO(CZ) 2A-1TP1/073 Institutional research plan: CEZ:AV0Z50110509 Keywords : oxidized cellulose * vascular tissue engineering * biofunctionalization Subject RIV: EI - Biotechnology ; Bionics

[Intramuscular injection of lentivirus-mediated EPAS1 gene improves hind limb ischemia and its mechanism in a rat model of peripheral artery vascular disease].

Science.gov (United States)

Wang, Zhihong; Gu, Hongbin; Yang, Fan; Xie, Huajie; Sheng, Lei; Li, Mingfei

2017-11-01

Objective To investigate the effect of over-expressed endothelial Per-Arnt-Sim domain protein 1 (EPAS1) on peripheral arterial disease (PAD) in a rat model. Methods PAD rat model was established by external iliac artery ligation followed by lentivirus-mediated EPAS1 gene injection into rat right adductor magnus. The models were evaluated by quantitative analysis of gait disturbance. The changes of blood flow in the posterior extremity of the rats were detected using laser Doppler. The expressions of EPAS1, hepatocyte growth factor (HGF), basic fibroblast growth factor (bFGF), and vascular endothelial growth factor (VEGF) mRNAs were tested by real-time quantitative PCR. The expression of α-smooth muscle actin (αSMA) was detected by immunohistochemical staining. Results Compared with lenti-EGFP group, rat hind limb function and circulation got recovered obviously 7 days after lenti-EPAS1 injection. The mRNA expressions of EPAS1, HGF, bFGF, and VEGF were up-regulated in the lenti-EPAS1-treated sites.The expression of αSMA showed an obvious increase in the lenti-EPAS1-treated muscles. Conclusion Over-expressed lenti-EPAS1 can promote angiogenesis via the up-regulation of EPAS1-related angiogenic factors in the muscles of the affected hind limb and reduce gait disturbance.

Phytochemical uptake following human consumption of Montmorency tart cherry (L. Prunus cerasus) and influence of phenolic acids on vascular smooth muscle cells in vitro.

Science.gov (United States)

Keane, Karen M; Bell, Phillip G; Lodge, John K; Constantinou, Costas L; Jenkinson, Sarah E; Bass, Rosemary; Howatson, Glyn

2016-06-01

To investigate the phytochemical uptake following human consumption of Montmorency tart cherry (L. Prunus cerasus) and influence of selected phenolic acids on vascular smooth muscle cells in vitro. In a randomised, double-blinded, crossover design, 12 healthy males consumed either 30 or 60 mL of Montmorency tart cherry concentrate. Following analysis of the juice composition, venous blood samples were taken before and 1, 2, 3, 5 and 8 h post-consumption of the beverage. In addition to examining some aspects of the concentrate contents, plasma concentrations of protocatechuic acid (PCA), vanillic acid (VA) and chlorogenic (CHL) acid were analysed by reversed-phase high-performance liquid chromatography (HPLC) with diode array for quantitation and mass spectrometry detection (LCMS) for qualitative purposes. Vascular smooth muscle cell migration and proliferation were also assessed in vitro. Both the 30 and 60 mL doses of Montmorency cherry concentrate contained high amounts of total phenolics (71.37 ± 0.11; 142.73 ± 0.22 mg/L) and total anthocyanins (62.47 ± 0.31; 31.24 ± 0.16 mg/L), as well as large quantities of CHL (0.205 ± 0.24; 0.410 ± 0.48 mg/L) and VA (0.253 ± 0.84; 0.506 ± 1.68 mg/L). HPLC/LCMS identified two dihydroxybenzoic acids (PCA and VA) in plasma following MC concentrate consumption. Both compounds were most abundant 1-2 h post-initial ingestion with traces detectable at 8 h post-ingestion. Cell migration was significantly influenced by the combination of PCA and VA, but not in isolation. There was no effect of the compounds on cell proliferation. These data show new information that phenolic compounds thought to exert vasoactive properties are bioavailable in vivo following MC consumption and subsequently can influence cell behaviour. These data may be useful for the design and interpretation of intervention studies investigating the health effects of Montmorency cherries.

Phosphotidylinositol turnover in vascular, uterine, fundal, and tracheal smooth muscle: effect of serotonin (5HT)

International Nuclear Information System (INIS)

Cohen, M.L.; Wittenauer, L.A.

1986-01-01

In brain, platelets, and aorta, 5HT has been reported to increase phosphotidylinositol turnover, an effect linked to 5HT 2 receptors. The authors examined the effect of 5HT on 3 H-inositol-1-phosphate ( 3 H-I-P) in tissues possessing 5HT 2 receptors that mediate contraction to 5HT (rat jugular vein, aorta, uterus and guinea pig trachea) and in a tissue in which contraction to 5HT is not mediated by 5HT 2 receptors (rat stomach fundus). Tissues were incubated (37 0 C, 95% O 2 , 5% CO 2 ) with 3 H-inositol (90 min), washed, LiCl 2 (10 mM) and 5HT added for 90 min, extracted, and 3 H-I-P eluted from a Dowex-1 column. Basal 3 H-I-P was 10-fold higher in the uterus than in the other tissues. 5HT (10 -6 -10 -4 M) increased 3 H-I-P in the jugular vein, aorta, and uterus but not in the trachea or fundus. Maximum increase was greatest in the jugular vein (8-fold) with an ED 50 of 0.4 μM 5HT. The selective 5HT 2 receptor blocker, LY53857 (10 -8 M) antagonized the increase in 3 H-I-P by 5HT in the jugular vein, aorta and uterus. Pargyline (10 -5 M) added to the trachea and fundus did not unmask an effect of 5HT (10 -4 M). These data suggest that (1) the jugular vein produced the most sensitive response to 5HT-induced increases in 3 H-I-P, (2) increases in 3 H-I-P by 5HT in smooth muscle may be linked to 5HT 2 receptors and (3) activation of 5HT 2 receptors as occurred in the trachea will not always increase 3 H-I-P

Role of renal vascular potassium channels in physiology and pathophysiology

DEFF Research Database (Denmark)

Salomonsson, Max; Brasen, Jens Christian; Sorensen, Charlotte Mehlin

2017-01-01

The control of renal vascular tone is important for the regulation of salt and water balance, blood pressure and the protection against damaging elevated glomerular pressure. The K+ conductance is a major factor in the regulation of the membrane potential (Vm ) in vascular smooth muscle (VSMC...... the ambiguous in vitro and in vivo results. We discuss the role of single types of K+ channels and the integrated function of several classes. We also deal with the possible role of renal vascular K+ channels in the pathophysiology of hypertension, diabetes mellitus and sepsis. This article is protected...

PDGF-DD, a novel mediator of smooth muscle cell phenotypic modulation, is upregulated in endothelial cells exposed to atherosclerosis-prone flow patterns.

Science.gov (United States)

Thomas, James A; Deaton, Rebecca A; Hastings, Nicole E; Shang, Yueting; Moehle, Christopher W; Eriksson, Ulf; Topouzis, Stavros; Wamhoff, Brian R; Blackman, Brett R; Owens, Gary K

2009-02-01

Platelet-derived growth factor (PDGF)-BB is a well-known smooth muscle (SM) cell (SMC) phenotypic modulator that signals by binding to PDGF alphaalpha-, alphabeta-, and betabeta-membrane receptors. PDGF-DD is a recently identified PDGF family member, and its role in SMC phenotypic modulation is unknown. Here we demonstrate that PDGF-DD inhibited expression of multiple SMC genes, including SM alpha-actin and SM myosin heavy chain, and upregulated expression of the potent SMC differentiation repressor gene Kruppel-like factor-4 at the mRNA and protein levels. On the basis of the results of promoter-reporter assays, changes in SMC gene expression were mediated, at least in part, at the level of transcription. Attenuation of the SMC phenotypic modulatory activity of PDGF-DD by pharmacological inhibitors of ERK phosphorylation and by a small interfering RNA to Kruppel-like factor-4 highlight the role of these two pathways in this process. PDGF-DD failed to repress SM alpha-actin and SM myosin heavy chain in mouse SMCs lacking a functional PDGF beta-receptor. Importantly, PDGF-DD expression was increased in neointimal lesions in the aortic arch region of apolipoprotein C-deficient (ApoE(-/-)) mice. Furthermore, human endothelial cells exposed to an atherosclerosis-prone flow pattern, as in vascular regions susceptible to the development of atherosclerosis, exhibited a significant increase in PDGF-DD expression. These findings demonstrate a novel activity for PDGF-DD in SMC biology and highlight the potential contribution of this molecule to SMC phenotypic modulation in the setting of disturbed blood flow.

Oxygenation decreases elastin secretion from rat ductus arteriosus smooth muscle cells.

Science.gov (United States)

Kawakami, Shoji; Minamisawa, Susumu

2015-08-01

The ductus arteriosus (DA), a fetal arterial connection between the main pulmonary artery and the descending aorta, normally closes immediately after birth. The oxygen concentration in the blood rises after birth, and in the DA this increase in oxygen concentration causes functional closure, which is induced by smooth muscle contraction. Previous studies have demonstrated that hypoxia and/or oxygenation affect vascular remodeling of various vessels. Therefore, we hypothesized that the rise in oxygen concentration would affect the vascular structure of the DA due to production of proteins secreted from DA smooth muscle cells (SMC). Liquid chromatography-tandem mass spectrometry was used to comprehensively investigate the secreted proteins in the supernatant of rat DA SMC harvested under hypoxic conditions (1% oxygen) or under normoxic conditions (21% oxygen). We found that the rise in oxygen concentration reduced the secretion of elastin from DA SMC. On reverse transcription-polymerase chain reaction, the expression of elastin mRNA was not significantly changed in DA SMC from hypoxic to normoxic conditions. Given that elastin forms internal elastic lamina and elastic fibers in the vascular muscle layers, and that a rise in oxygen concentration reduced the secretion of elastin, this suggests that the rise in blood oxygen concentration after birth reduces the secretion of elastin, and therefore may play a role in DA structural remodeling after birth. © 2015 Japan Pediatric Society.

Gentiana lutea exerts anti-atherosclerotic effects by preventing endothelial inflammation and smooth muscle cell migration.

Science.gov (United States)

Kesavan, R; Chandel, S; Upadhyay, S; Bendre, R; Ganugula, R; Potunuru, U R; Giri, H; Sahu, G; Kumar, P Uday; Reddy, G Bhanuprakash; Joksic, G; Bera, A K; Dixit, Madhulika

2016-04-01

Studies suggest that Gentiana lutea (GL), and its component isovitexin, may exhibit anti-atherosclerotic properties. In this study we sought to investigate the protective mechanism of GL aqueous root extract and isovitexin on endothelial inflammation, smooth muscle cell migation, and on the onset and progression of atherosclerosis in streptozotocin (STZ)-induced diabetic rats. Our results show that both GL extract and isovitexin, block leukocyte adhesion and generation of reactive oxygen species in human umbilical vein endothelial cells (HUVECs) and rat aortic smooth muscle cells (RASMCs), following TNF-alpha and platelet derived growth factor-BB (PDGF-BB) challenges respectively. Both the extract and isovitexin blocked TNF-α induced expression of ICAM-1 and VCAM-1 in HUVECs. PDGF-BB induced migration of RASMCs and phospholipase C-γ activation, were also abrogated by GL extract and isovitexin. Fura-2 based ratiometric measurements demonstrated that, both the extact, and isovitexin, inhibit PDGF-BB mediated intracellular calcium rise in RASMCs. Supplementation of regular diet with 2% GL root powder for STZ rats, reduced total cholesterol in blood. Oil Red O staining demonstrated decreased lipid accumulation in aortic wall of diabetic animals upon treatment with GL. Medial thickness and deposition of collagen in the aortic segment of diabetic rats were also reduced upon supplementation. Immunohistochemistry demonstrated reduced expression of vascular cell adhesion molecule-1 (VCAM-1), inducible nitric oxide synthase (iNOS), and vascular endothelial cadherin (VE-cadherin) in aortic segments of diabetic rats following GL treatment. Thus, our results support that GL root extract/powder and isovitexin exhibit anti-atherosclerotic activities. Copyright © 2016 The Italian Society of Diabetology, the Italian Society for the Study of Atherosclerosis, the Italian Society of Human Nutrition, and the Department of Clinical Medicine and Surgery, Federico II University

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

Science.gov (United States)

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

2016-12-28

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

Mechanical stretch modulates microRNA 21 expression, participating in proliferation and apoptosis in cultured human aortic smooth muscle cells.

Directory of Open Access Journals (Sweden)

Jian tao Song

Full Text Available OBJECTIVES: Stretch affects vascular smooth muscle cell proliferation and apoptosis, and several responsible genes have been proposed. We tested whether the expression of microRNA 21 (miR-21 is modulated by stretch and is involved in stretch-induced proliferation and apoptosis of human aortic smooth muscle cells (HASMCs. METHODS AND RESULTS: RT-PCR revealed that elevated stretch (16% elongation, 1 Hz increased miR-21 expression in cultured HASMCs, and moderate stretch (10% elongation, 1 Hz decreased the expression. BrdU incorporation assay and cell counting showed miR-21 involved in the proliferation of HASMCs mediated by stretch, likely by regulating the expression of p27 and phosphorylated retinoblastoma protein (p-Rb. FACS analysis revealed that the complex of miR-21 and programmed cell death protein 4 (PDCD4 participated in regulating apoptosis with stretch. Stretch increased the expression of primary miR-21 and pre-miR-21 in HASMCs. Electrophoretic mobility shift assay (EMSA demonstrated that stretch increased NF-κB and AP-1 activities in HASMCs, and blockade of AP-1 activity by c-jun siRNA significantly suppressed stretch-induced miR-21 expression. CONCLUSIONS: Cyclic stretch modulates miR-21 expression in cultured HASMCs, and miR-21 plays important roles in regulating proliferation and apoptosis mediated by stretch. Stretch upregulates miR-21 expression at least in part at the transcription level and AP-1 is essential for stretch-induced miR-21 expression.

Effects of gamma rays on non-vascular smooth muscles contractions (rat small intestine)

International Nuclear Information System (INIS)

Azroony, R.; Ksies, F.; Alya, G.

2003-03-01

In this experiment, the contractile response evoked by activating the membranous cholinergic and adrenergic receptors in the smooth muscular fibres isolated from jejunum in rat small intestine is studied. Also the effect of gamma rays on regulating this contractile response after exposing the whole body of the animals to different doses of gamma rays (3, 5 and 7 Gy) emitted from 60 Co source is studied. Results show that irradiation lessens the sensitivity of muscarinic cholinergic receptors to their agonists in a dose dependent manner. And there is an important shift on irradiated rats where the maximum effect of acetylcholine (E max) can be obtained in higher concentrations of acetylcholine. Concerning the effects of gamma rays on adrenergic receptors, our results show that irradiation, also, decreases the sensitivity of α1 adrenergic receptors to their agonists, and this decrease is represented in a decrease of the irradiated muscular fibers response to the inhibitory effect of phenylephrine (more specific to α1 adrenergic receptors than α2 adrenergic receptors) in a dose dependent manner. While we have found that α2 adrenergic receptors have no important effect on regulating the contractile response of the smooth muscular fibers in the rat jejunum neither in smooth muscular fibers isolated from control animals nor in those fibers which where isolated from irradiated animals. (author)

Effect of 125I seeds and 103Pd stents on proliferation of vascular smooth muscle cells

International Nuclear Information System (INIS)

Zhu Jun; Zhu Ruisen

2004-01-01

To establish the theoretical and practical base for implementing radioactive stents aft PTCA in order to prevent restenosis, in vitro observation was taken over the effects of 12 '5I-seeds and 103 Pd-implanted stents on the vascular smooth muscle cell (VSMC) proliferation. In vitro VSMC model from guinea-pig aortic arteries was established using adherent cell culture methods. The effects of 125 I-seeds and 103 Pd-implanted stents on the VSMC proliferation, with or without fetal bovine serum (FCS), were investigated through cell counting methods and 3 H-TDR implementation tests. It was shown that (1) 10% FCS significantly promoted the DNA synthesis of VSMC (P 125 I-seeds and 103 Pd-implanted stents inhibited the VSMC DNA synthesis in dose-dependent manner, regardless of 10% FCS inducement. At lower radioactive doses, neither 125 I-seeds (18.5-74 kBq) nor 103 Pd-implanted stents (1.48-2.96 MBq) exhibited distinctive effects on the VSMC DNA synthesis (P>0.05); and (3) 48 hour exposure from 125 I-seeds at 128 kBq or 10 '3Pd-implanted stents at 7.4 MBq did not result in VSMC morphological alteration, but 125 I-seeds at 370 kBq caused cells' morphological changes. Therefore both 125 I-seeds and 103 Pd-implanted stents inhibit the in vitro VSMC DNA synthesis, and the inhibition effects are significantly related to their exposure duration and doses. (authors)

Divergent effects of 17-{beta}-estradiol on human vascular smooth muscle and endothelial cell function diminishes TNF-{alpha}-induced neointima formation

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Nintasen, Rungrat [Division of Cardiovascular Medicine, Leeds Institute of Genetics, Health and Therapeutics, University of Leeds, Leeds LS2 9JT (United Kingdom); Multidisciplinary Cardiovascular Research Center (MCRC), University of Leeds, Leeds LS2 9JT (United Kingdom); Department of Tropical Pathology, Faculty of Tropical Medicine, Mahidol University (Thailand); Riches, Kirsten; Mughal, Romana S. [Division of Cardiovascular Medicine, Leeds Institute of Genetics, Health and Therapeutics, University of Leeds, Leeds LS2 9JT (United Kingdom); Multidisciplinary Cardiovascular Research Center (MCRC), University of Leeds, Leeds LS2 9JT (United Kingdom); Viriyavejakul, Parnpen; Chaisri, Urai; Maneerat, Yaowapa [Department of Tropical Pathology, Faculty of Tropical Medicine, Mahidol University (Thailand); Turner, Neil A. [Division of Cardiovascular Medicine, Leeds Institute of Genetics, Health and Therapeutics, University of Leeds, Leeds LS2 9JT (United Kingdom); Multidisciplinary Cardiovascular Research Center (MCRC), University of Leeds, Leeds LS2 9JT (United Kingdom); Porter, Karen E., E-mail: medkep@leeds.ac.uk [Division of Cardiovascular Medicine, Leeds Institute of Genetics, Health and Therapeutics, University of Leeds, Leeds LS2 9JT (United Kingdom); Multidisciplinary Cardiovascular Research Center (MCRC), University of Leeds, Leeds LS2 9JT (United Kingdom)

2012-04-20

Highlights: Black-Right-Pointing-Pointer TNF-{alpha} augments neointimal hyperplasia in human saphenous vein. Black-Right-Pointing-Pointer TNF-{alpha} induces detrimental effects on endothelial and smooth muscle cell function. Black-Right-Pointing-Pointer Estradiol exerts modulatory effects on TNF-induced vascular cell functions. Black-Right-Pointing-Pointer The modulatory effects of estradiol are discriminatory and cell-type specific. -- Abstract: Coronary heart disease (CHD) is a condition characterized by increased levels of proinflammatory cytokines, including tumor necrosis factor-{alpha} (TNF-{alpha}). TNF-{alpha} can induce vascular endothelial cell (EC) and smooth muscle cell (SMC) dysfunction, central events in development of neointimal lesions. The reduced incidence of CHD in young women is believed to be due to the protective effects of estradiol (E2). We therefore investigated the effects of TNF-{alpha} on human neointima formation and SMC/EC functions and any modulatory effects of E2. Saphenous vein (SV) segments were cultured in the presence of TNF-{alpha} (10 ng/ml), E2 (2.5 nM) or both in combination. Neointimal thickening was augmented by incubation with TNF-{alpha}, an effect that was abolished by co-culture with E2. TNF-{alpha} increased SV-SMC proliferation in a concentration-dependent manner that was optimal at 10 ng/ml (1.5-fold increase), and abolished by E2 at all concentrations studied (1-50 nM). Surprisingly, E2 itself at low concentrations (1 and 5 nM) stimulated SV-SMC proliferation to a level comparable to that of TNF-{alpha} alone. SV-EC migration was significantly impaired by TNF-{alpha} (42% of control), and co-culture with E2 partially restored the ability of SV-EC to migrate and repair the wound. In contrast, TNF-{alpha} increased SV-SMC migration by 1.7-fold, an effect that was completely reversed by co-incubation with E2. Finally, TNF-{alpha} potently induced ICAM-1 and VCAM-1 expression in both SV-EC and SV-SMC. However there

Alpha1a-Adrenoceptor Genetic Variant Triggers Vascular Smooth Muscle Cell Hyperproliferation and Agonist Induced Hypertrophy via EGFR Transactivation Pathway.

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Irina Gradinaru

Full Text Available α1a Adrenergic receptors (α1aARs are the predominant AR subtype in human vascular smooth muscle cells (SMCs. α1aARs in resistance vessels are crucial in the control of blood pressure, yet the impact of naturally occurring human α1aAR genetic variants in cardiovascular disorders remains poorly understood. To this end, we present novel findings demonstrating that 3D cultures of vascular SMCs expressing human α1aAR-247R (247R genetic variant demonstrate significantly increased SMC contractility compared with cells expressing the α1aAR-WT (WT receptor. Stable expression of 247R genetic variant also triggers MMP/EGFR-transactivation dependent serum- and agonist-independent (constitutive hyperproliferation and agonist-dependent hypertrophy of SMCs. Agonist stimulation reduces contractility Using pathway-specific inhibitors we determined that the observed hyperproliferation of 247R-expressing cells is triggered via β-arrestin1/Src/MMP-2/EGFR/ERK-dependent mechanism. MMP-2-specific siRNA inhibited 247R-triggered hyperproliferation indicating MMP-2 involvement in 247R-triggered hyperproliferation in SMCs. β-arrestin1-specific shRNA also inhibited 247R-triggered hyperproliferation but did not affect hypertrophy in 247R-expressing SMCs, indicating that agonist-dependent hypertrophy is independent of β-arrestin1. Our data reveal that in different cardiovascular cells the same human receptor genetic variant can activate alternative modulators of the same signaling pathway. Thus, our findings in SMCs demonstrate that depending on the type of cells expressing the same receptor (or receptor variant, different target-specific inhibitors could be used to modulate aberrant hyperproliferative or hypertrophic pathways in order to restore normal phenotype.

Atorvastatin Protects Vascular Smooth Muscle Cells From TGF-β1-Stimulated Calcification by Inducing Autophagy via Suppression of the β-Catenin Pathway

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Demin Liu

2014-01-01

Full Text Available Background: Arterial calcification is a major event in the progression of atherosclerosis. It is reported that statins exhibit various protective effects against vascular smooth muscle cell (VSMC inflammation and proliferation in cardiovascular remodeling. Although statins counteract atherosclerosis, the molecular mechanisms of statins on the calcium release from VSMCs have not been clearly elucidated. Methods: Calcium content of VSMCs was measured using enzyme-linked immunosorbent assay (ELISA. The expression of proteins involved in cellular transdifferentiation was analyzed by western blot. Cell autophagy was measured by fluorescence microscopic analysis for acridine orange staining and transmission electron microscopy analysis. The autophagic inhibitors (3-MA, chloroquine, NH4Cl and bafilomycin A1 and β-catenin inhibitor JW74 were used to assess the effects of atorvastatin on autophagy and the involvement of β-catenin on cell calcification respectively. Furthermore, cell transfection was performed to overexpress β-catenin. Results: In VSMCs, atorvastatin significantly suppressed transforming growth factor-β1 (TGF-β1-stimulated calcification, accompanied by the induction of autophagy. Downregulation of autophagy with autophagic inhibitors significantly suppressed the inhibitory effect of atorvastatin on cell calcification. Moreover, the beneficial effect of atorvastatin on calcification and autophagy was reversed by β-catenin overexpression. Conversely, JW74 supplement enhanced this effect. Conclusion: These data demonstrated that atorvastatin protect VSMC from TGF-β1-stimulated calcification by inducing autophagy through suppression of the β-catenin pathway, identifying autophagy induction might be a therapeutic strategy for use in vascular calcification.

Betulinic Acid Inhibits Growth of Cultured Vascular Smooth Muscle Cells In Vitro by Inducing G1 Arrest and Apoptosis

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Raja Kumar Vadivelu

2012-01-01

Full Text Available Betulinic acid is a widely available plant-derived triterpene which is reported to possess selective cytotoxic activity against cancer cells of neuroectodermal origin and leukemia. However, the potential of betulinic acid as an antiproliferative and cytotoxic agent on vascular smooth muscle (VSMC is still unclear. This study was carried out to demonstrate the antiproliferative and cytotoxic effect of betulinic acid on VSMCs using 3-[4,5-dimethylthizol-2-yl]-2,5-diphenyltetrazolium bromide (MTT assay, flow cytometry cell cycle assay, BrdU proliferation assay, acridine orange/propidium iodide staining, and comet assay. Result from MTT and BrdU assays indicated that betulinic acid was able to inhibit the growth and proliferation of VSMCs in a dose-dependent manner with IC50 of 3.8 μg/mL significantly (P<0.05. Nevertheless, betulinic acid exhibited G1 cell cycle arrest in flow cytometry cell cycle profiling and low level of DNA damage against VSMC in acridine orange/propidium iodide and comet assay after 24 h of treatment. In conclusion, betulinic acid induced G1 cell cycle arrest and dose-dependent DNA damage on VSMC.

Platelet Vascular Endothelial Growth Factor is a Potential Mediator of Transfusion-Related Acute Lung Injury.

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Maloney, James P; Ambruso, Daniel R; Voelkel, Norbert F; Silliman, Christopher C

The occurrence of non-hemolytic transfusion reactions is highest with platelet and plasma administration. Some of these reactions are characterized by endothelial leak, especially transfusion related acute lung injury (TRALI). Elevated concentrations of inflammatory mediators secreted by contaminating leukocytes during blood product storage may contribute to such reactions, but platelet-secreted mediators may also contribute. We hypothesized that platelet storage leads to accumulation of the endothelial permeability mediator vascular endothelial growth factor (VEGF), and that intravascular administration of exogenous VEGF leads to extensive binding to its lung receptors. Single donor, leukocyte-reduced apheresis platelet units were sampled over 5 days of storage. VEGF protein content of the centrifuged supernatant was determined by ELISA, and the potential contribution of VEGF from contaminating leukocytes was quantified. Isolated-perfused rat lungs were used to study the uptake of radiolabeled VEGF administered intravascularly, and the effect of unlabeled VEGF on lung leak. There was a time-dependent release of VEGF into the plasma fraction of the platelet concentrates (62 ± 9 pg/ml on day one, 149 ± 23 pg/ml on day 5; mean ± SEM, pproducts.

Delayed effects of cold atmospheric plasma on vascular cells

NARCIS (Netherlands)

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

2008-01-01

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

Adhesion, Growth, and Maturation of Vascular Smooth Muscle Cells on Low-Density Polyethylene Grafted with Bioactive Substances

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Martin Parizek

2013-01-01

Full Text Available The attractiveness of synthetic polymers for cell colonization can be affected by physical, chemical, and biological modification of the polymer surface. In this study, low-density polyethylene (LDPE was treated by an Ar+ plasma discharge and then grafted with biologically active substances, namely, glycine (Gly, polyethylene glycol (PEG, bovine serum albumin (BSA, colloidal carbon particles (C, or BSA+C. All modifications increased the oxygen content, the wettability, and the surface free energy of the materials compared to the pristine LDPE, but these changes were most pronounced in LDPE with Gly or PEG, where all the three values were higher than in the only plasma-treated samples. When seeded with vascular smooth muscle cells (VSMCs, the Gly- or PEG-grafted samples increased mainly the spreading and concentration of focal adhesion proteins talin and vinculin in these cells. LDPE grafted with BSA or BSA+C showed a similar oxygen content and similar wettability, as the samples only treated with plasma, but the nano- and submicron-scale irregularities on their surface were more pronounced and of a different shape. These samples promoted predominantly the growth, the formation of a confluent layer, and phenotypic maturation of VSMC, demonstrated by higher concentrations of contractile proteins alpha-actin and SM1 and SM2 myosins. Thus, the behavior of VSMC on LDPE can be regulated by the type of bioactive substances that are grafted.

Increased atrial natriuretic factor receptor density in cultured vascular smooth muscle cells of the spontaneously hypertensive rat

International Nuclear Information System (INIS)

Khalil, F.; Fine, B.; Kuriyama, S.; Hatori, N.; Nakamura, A.; Nakamura, M.; Aviv, A.

1987-01-01

To explore the role of the atrial natriuretic factor (ANF) system in the pathophysiology of hypertension we examined the binding kinetics of synthetic ANF to cultured vascular smooth muscle cells (VSMCs) derived from the spontaneously hypertensive rat (SHR) and two normotensive controls-the Wistar Kyoto (WKY) and American Wistar (W). The number of maximal binding sites (Bmax) per cell (mean +/- SEM; X10(3] were: SHR = 278.0 +/- 33.0, WKY = 28.3 +/- 7.1 and W = 26.6 +/- 4.2. The differences between the SHR and normotensive strains were significant at p less than 0.001. The equilibrium dissociation constant (Kd; X 10(-9)M) was higher in SHR VSMCs (0.94 +/- 0.14) than in WKY (0.22 +/- 0.09; p less than 0.01) and W (0.39 +/- 0.14; p less than 0.02) cells. The plasma levels of the immunoreactive ANF were higher in SHR than the normotensive controls. We suggest that the relatively greater ANF receptor density in cultured VSMCs of the SHR represents a response to the in vitro environment which is relatively more deficient in ANF for VSMCs of the SHR as compared with the normotensive rats. Thus, the capacity of the SHR VSMC to regulate ANF receptor density appears to be independent of the blood pressure level

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

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

2001-11-30

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

Experimental study of the effect of 103Pd on the proliferation and apoptosis of vascular smooth muscle cells

International Nuclear Information System (INIS)

Luo Quanyong; Zhu Jun; Chen Libo; Lu Hankui; Zhu Ruisen

2002-01-01

Objective: To investigate the ability of γ emitting radionuclide 103 Pd to inhibit the vascular smooth muscle cell (SMC) proliferation and to induce its apoptosis in vitro. Methods: 103 Pd solution was added to the culture medium to irradiate SMCs for 72 h and non-radioactive Pd solution was added as control. 3 H-TdR incorporation test was used to detect the effect of 103 Pd on the proliferation of SMCs. Flow cytometer was used to detect the apoptotic SMCs. Results: The results showed that inhibition of SMC proliferation was evident and the effects were dose-dependant. Inhibition rate of SMC proliferation by 1.85 MBq 103 Pd was 2.3% , which was not significant. The inhibition rate increased from 41.6% to 91.2% as the dose of 103 Pd increased from 7.4 to 37.0 MBq, and the proliferation of SMCs was repressed significantly then. The apoptosis rate was extremely low (less than 4.0% ) with the 103 pd dose escalating from 1.85 to 37.0 MBq. Conclusions: This study suggests that proliferation of SMCs can be repressed effectively in vitro by 103 pd. 103 Pd can be used to inhibit the neointimal proliferation. 103 Pd radioactive stent implantation can be employed as a possible novel means to prevent restenosis

Proofs concerning the existence, in the blood of hypertensive patients, of some serum factors influencing the vascular smooth muscle and the myocardium physiology.

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Mocanu, M; Botea, S; Dragomir, C T

1991-01-01

Starting from the existence of some autoimmune diseases (i.e. bronchial asthma or miastenia gravis) we asked ourselves if some plasmatic factors do exist, influencing the receptor--mediator relations in cardiovascular system during some illnesses having unknown etiology, as arterial hypertension. For this reason, in this work was tested the hypothesis that, in some chronic cardiovascular diseases would exist factors circulating and affecting the functions of the cellular membranes of the arterial wall, particularly of the smooth muscle cells and myocardial cells. Our results show a significant modification of the calcium fluxes and of some neuromediators uptake at the hypertensive patients.

Metformin inhibits inflammatory response via AMPK–PTEN pathway in vascular smooth muscle cells

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Kim, Sun Ae; Choi, Hyoung Chul

2012-01-01

Highlights: ► PTEN was induced by metformin and inhibited by compound C and AMPK siRNA. ► Metformin suppressed TNF-α-induced COX-2 and iNOS mRNA expression. ► Compound C and bpv (pic) increased iNOS and COX-2 protein expression. ► NF-κB activation was restored by inhibiting AMPK and PTEN. ► AMPK and PTEN regulated TNF-α-induced ROS production in VSMCs. -- Abstract: Atherosclerosis is a chronic inflammation of the coronary arteries. Vascular smooth muscle cells (VSMCs) stimulated by cytokines and chemokines accelerate the inflammatory response and migrate to the injured endothelium during the progression of atherosclerosis. Activation of AMP activated protein kinase (AMPK), a key sensor maintaining metabolic homeostasis, suppresses the inflammatory response. However, how AMPK regulates the inflammatory response is poorly understood. To identify the mechanism of this response, we focused on phosphatase and tensin homolog (PTEN), which is a negative regulator of inflammation. We investigated that activation of AMPK-induced PTEN expression and suppression of the inflammatory response through the AMPK–PTEN pathway in VSMCs. We treated with the well-known AMPK activator metformin to induce PTEN expression. PTEN was induced by metformin (2 mM) and inhibited by compound C (10 μM) and AMPK siRNA. Tumor necrosis factor-alpha (TNF-α) was used to induce inflammation. The inflammatory response was confirmed by cyclooxygenase (COX)-2, inducible nitric oxide synthase (iNOS) expression, and activation of nuclear factor (NF)-κB. Metformin suppressed COX-2 and iNOS mRNA and protein expression dose dependently. Treatment with compound C and bpv (pic) in the presence of metformin, iNOS and COX-2 protein expression increased. NF-κB activation decreased in response to metformin and was restored by inhibiting AMPK and PTEN. Inhibiting AMPK and PTEN restored ROS levels stimulated with TNF-α. Taken together, PTEN could be a possible downstream regulator of AMPK, and the

EMMPRIN (CD147/basigin) mediates platelet-monocyte interactions in vivo and augments monocyte recruitment to the vascular wall.

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Schulz, C; von Brühl, M-L; Barocke, V; Cullen, P; Mayer, K; Okrojek, R; Steinhart, A; Ahmad, Z; Kremmer, E; Nieswandt, B; Frampton, J; Massberg, S; Schmidt, R

2011-05-01

Platelets play a central role in hemostasis, in inflammatory diseases such as atherosclerosis, and during thrombus formation following vascular injury. Thereby, platelets interact intensively with monocytes and enhance their recruitment to the vascular wall. To investigate the role of the extracellular matrix metalloproteinase inducer (EMMPRIN) in platelet-monocyte interactions. Isolated human monocytes were perfused in vitro over firmly adherent platelets to allow investigation of the role of EMMPRIN in platelet-monocyte interactions under flow conditions. Monocytes readily bound to surface-adherent platelets. Both antibody blockade and gene silencing of monocyte EMMPRIN substantially attenuated firm adhesion of monocytes to platelets at arterial and venous shear rates. In vivo, platelet interactions with the murine monocyte cell line ANA-1 were significantly decreased when ANA-1 cells were pretreated with EMMPRIN-silencing small interfering RNA prior to injection into wild-type mice. Using intravital microscopy, we showed that recruitment of EMMPRIN-silenced ANA-1 to the injured carotid artery was significantly reduced as compared with control cells. Further silencing of EMMPRIN resulted in significantly fewer ANA-1-platelet aggregates in the mouse circulation as determined by flow cytometry. Finally, we identified glycoprotein (GP)VI as a critical corresponding receptor on platelets that mediates interaction with monocyte EMMPRIN. Thus, blocking of GPVI inhibited the effect of EMMPRIN on firm monocyte adhesion to platelets under arterial flow conditions in vitro, and abrogated EMMPRIN-mediated platelet-monocyte aggregate formation in vivo. EMMPRIN supports platelet-monocyte interactions and promotes monocyte recruitment to the arterial wall. Therefore, EMMPRIN might represent a novel target to reduce vascular inflammation and atherosclerotic lesion development. © 2011 International Society on Thrombosis and Haemostasis.

Endocrine factors related to changes in total peripheral vascular resistance after treatment of thyrotoxic and hypothyroid patients

NARCIS (Netherlands)

Diekman, M. J.; Harms, M. P.; Endert, E.; Wieling, W.; Wiersinga, W. M.

2001-01-01

Total peripheral vascular resistance (TPR) decreases in thyrotoxicosis and increases in hypothyroidism. Several mechanisms may be involved, including adaptation to changes in heat production and direct non-genomic effects of tri-iodothyronine (T3) on vascular smooth muscle cells. The aim of this

Guiding the orientation of smooth muscle cells on random and aligned polyurethane/collagen nanofibers.

Science.gov (United States)

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

2014-09-01

Fabricating scaffolds that can simulate the architecture and functionality of native extracellular matrix is a huge challenge in vascular tissue engineering. Various kinds of materials are engineered via nano-technological approaches to meet the current challenges in vascular tissue regeneration. During this study, nanofibers from pure polyurethane and hybrid polyurethane/collagen in two different morphologies (random and aligned) and in three different ratios of polyurethane:collagen (75:25; 50:50; 25:75) are fabricated by electrospinning. The fiber diameters of the nanofibrous scaffolds are in the range of 174-453 nm and 145-419 for random and aligned fibers, respectively, where they closely mimic the nanoscale dimensions of native extracellular matrix. The aligned polyurethane/collagen nanofibers expressed anisotropic wettability with mechanical properties which is suitable for regeneration of the artery. After 12 days of human aortic smooth muscle cells culture on different scaffolds, the proliferation of smooth muscle cells on hybrid polyurethane/collagen (3:1) nanofibers was 173% and 212% higher than on pure polyurethane scaffolds for random and aligned scaffolds, respectively. The results of cell morphology and protein staining showed that the aligned polyurethane/collagen (3:1) scaffold promote smooth muscle cells alignment through contact guidance, while the random polyurethane/collagen (3:1) also guided cell orientation most probably due to the inherent biochemical composition. Our studies demonstrate the potential of aligned and random polyurethane/collagen (3:1) as promising substrates for vascular tissue regeneration. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

Cyclic Stretch Alters Vascular Reactivity of Mouse Aortic Segments

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Arthur Leloup

2017-10-01

Full Text Available Large, elastic arteries buffer the pressure wave originating in the left ventricle and are constantly exposed to higher amplitudes of cyclic stretch (10% than muscular arteries (2%. As a crucial factor for endothelial and smooth muscle cell function, cyclic stretch has, however, never been studied in ex vivo aortic segments of mice. To investigate the effects of cyclic stretch on vaso-reactivity of mouse aortic segments, we used the Rodent Oscillatory Tension Set-up to study Arterial Compliance (ROTSAC. The aortic segments were clamped at frequencies of 6–600 bpm between two variable preloads, thereby mimicking dilation as upon left ventricular systole and recoiling as during diastole. The preloads corresponding to different transmural pressures were chosen to correspond to a low, normal or high amplitude of cyclic stretch. At different time intervals, cyclic stretch was interrupted, the segments were afterloaded and isometric contractions by α1-adrenergic stimulation with 2 μM phenylephrine in the absence and presence of 300 μM L-NAME (eNOS inhibitor and/or 35 μM diltiazem (blocker of voltage-gated Ca2+ channels were measured. As compared with static or cyclic stretch at low amplitude (<10 mN or low frequency (0.1 Hz, cyclic stretch at physiological amplitude (>10 mN and frequency (1–10 Hz caused better ex vivo conservation of basal NO release with time after mounting. The relaxation of PE-precontracted segments by addition of ACh to stimulate NO release was unaffected by cyclic stretch. In the absence of basal NO release (hence, presence of L-NAME, physiological in comparison with aberrant cyclic stretch decreased the baseline tension, attenuated the phasic contraction by phenylephrine in the absence of extracellular Ca2+ and shifted the smaller tonic contraction more from a voltage-gated Ca2+ channel-mediated to a non-selective cation channel-mediated. Data highlight the need of sufficient mechanical activation of endothelial and

Airway smooth muscle cells : regulators of airway inflammation

NARCIS (Netherlands)

Zuyderduyn, Suzanne

2007-01-01

Airways from asthmatic subjects are more responsive to bronchoconstrictive stimuli than airways from healthy subjects. Airway smooth muscle (ASM) cells mediate contraction of the airways by responding to the bronchoconstrictive stimuli, which was thought to be the primary role of ASM cells. In this

Experimental comparison study of the tissue characteristics in transjugular intrahepatic portosystemic shunt and vascular stent

International Nuclear Information System (INIS)

Lu Qin; An Yanli; Deng Gang; Fang Wen; Zhu Guangyu; Niu Huanzhang; Yu Hui; Li Guozhao; Teng Gaojun; Wang Zhen; Wei Xiaoying

2009-01-01

Objective: To investigate the tissue characteristics within vascular stent and transjugular intrahepatic portosystemic shunt(TIPS) on swine and to provide more information for the understanding and prevention of vascular stent and TIPS restenosis. Methods: Animal models for TIPS were built in 6 swine and vascular stents were implanted in iliac veins simultaneously. 14-28 days after the operation, the 6 swine were killed to remove the TIPS and vascular stent and the pathological examinations were performed on the tissues within the shunt and stent. The similarities and differences of the tissues within the shunt and stent were analyzed with Krttskal Wallis test. Results: Restenosis of TIPS occurred in 4 models and complete occlusion were seen in 2, while all vascular stents were patent and coated with a thin layer of intimal tissue. Electron microscopic results showed that the tissues in restenotic TIPS were loose and with more extra matrix and fibers, and less smooth muscle, fibroblastic and myofibroblastic cells with different and irregular shape and rich secretory granules. The tissues in patent TIPS contained more extra fibers, smooth muscle and fibroblastic cells with normal organelle. The intimal tissues in vascular stent contained more fibers and fibroblasts cells, less smooth muscle cells. On immunohistochemical staining, the tissues in restenotic and patent TIPS as well as the intimal tissues in vascular stent had strong positive expression for anti-SMC- actin-α, the expression were gradually weakened for PCNA, the intimal tissues in vascular stent had a strong positive expression for vimentin, while the expression of the tissues in restenotic and patent TIPS were weakened gradually. For myoglobulin, the tissues in restenotic TIPS had weakly positive expression, the expression in patent TIPS and vascular stent were almost negative. Western blot results for TGF-β showed that the absorbance ratios of the intima tissues in vascular stent, normal vascular

Micro- and nanostructured Al{sub 2}O{sub 3} surfaces for controlled vascular endothelial and smooth muscle cell adhesion and proliferation

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Aktas, Cenk, E-mail: cenk.aktas@inm-gmbh.de [INM - Leibniz Institute for New Materials, CVD/Biosurfaces Division, 66123 Saarbruecken (Germany); Doerrschuck, Eva; Schuh, Cathrin [Clinic of Paediatric Cardiology, Saarland University, Building 9, 66424 Homburg (Germany); Miro, Marina Martinez; Lee, Juseok [INM - Leibniz Institute for New Materials, CVD/Biosurfaces Division, 66123 Saarbruecken (Germany); Puetz, Norbert; Wennemuth, Gunther [Department of Anatomy and Cell Biology, Saarland University, Building 61, 66424 Homburg (Germany); Metzger, Wolfgang; Oberringer, Martin [Department of Trauma-, Hand- and Reconstructive Surgery, Saarland University, Building 57, 66424 Homburg (Germany); Veith, Michael [INM - Leibniz Institute for New Materials, CVD/Biosurfaces Division, 66123 Saarbruecken (Germany); Department of Inorganic Chemistry, University of Saarland, Building C 4 1, 66123 Saarbruecken (Germany); Abdul-Khaliq, Hashim [Clinic of Paediatric Cardiology, Saarland University, Building 9, 66424 Homburg (Germany)

2012-07-01

The effect of the micro- and nanotopography on vascular cell-surface interaction is investigated using nano- and microstructured Al{sub 2}O{sub 3} as model substrate. Two different nanostructured Al{sub 2}O{sub 3} surfaces composed of low density (LD) and high density (HD) nanowires (NWs) were synthesized by chemical vapour deposition (CVD) and commercially available microstructured Al{sub 2}O{sub 3} plates were used for comparison. A clear diverging response of human umbilical vein endothelial cells (HUVEC) and human umbilical vein smooth muscle cells (HUVSMC) was observed on these nano- and microstructured surfaces. LD Al{sub 2}O{sub 3} NWs seem to enhance the proliferation of HUVECs selectively. This selective control of the cell-surface interaction by topography may represent a key issue for the future stent material design. - Highlights: Black-Right-Pointing-Pointer Nanostructured alumina surfaces triggers selective adhesion and proliferation of endothelial cells. Black-Right-Pointing-Pointer Catalyst free synthesis of nanowires. Black-Right-Pointing-Pointer Topography induces selective cell response.

Vascular tissue engineering by computer-aided laser micromachining.

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Doraiswamy, Anand; Narayan, Roger J

2010-04-28

Many conventional technologies for fabricating tissue engineering scaffolds are not suitable for fabricating scaffolds with patient-specific attributes. For example, many conventional technologies for fabricating tissue engineering scaffolds do not provide control over overall scaffold geometry or over cell position within the scaffold. In this study, the use of computer-aided laser micromachining to create scaffolds for vascular tissue networks was investigated. Computer-aided laser micromachining was used to construct patterned surfaces in agarose or in silicon, which were used for differential adherence and growth of cells into vascular tissue networks. Concentric three-ring structures were fabricated on agarose hydrogel substrates, in which the inner ring contained human aortic endothelial cells, the middle ring contained HA587 human elastin and the outer ring contained human aortic vascular smooth muscle cells. Basement membrane matrix containing vascular endothelial growth factor and heparin was to promote proliferation of human aortic endothelial cells within the vascular tissue networks. Computer-aided laser micromachining provides a unique approach to fabricate small-diameter blood vessels for bypass surgery as well as other artificial tissues with complex geometries.

Natriuretic peptide receptor-C activation attenuates angiotensin II-induced enhanced oxidative stress and hyperproliferation of aortic vascular smooth muscle cells.

Science.gov (United States)

Madiraju, Padma; Hossain, Ekhtear; Anand-Srivastava, Madhu B

2018-02-07

We showed previously that natriuretic peptide receptor-C (NPR-C) agonist, C-ANP 4-23 , attenuated the enhanced expression of Giα proteins in vascular smooth muscle cells (VSMC) from spontaneously hypertensive rats (SHR) through the inhibition of enhanced oxidative stress. Since the enhanced levels of endogenous angiotensin II (Ang II) contribute to the overexpression of Giα proteins and augmented oxidative stress in VSMC from SHR, the present study was undertaken to investigate if C-ANP 4-23 could also attenuate angiotensin II (Ang II)-induced oxidative stress and associated signaling. Ang II treatment of aortic VSMC augmented the levels of superoxide anion (O 2 - ), NADPH oxidase activity, and the expression of NADPH oxidase subunits and C-ANP 4-23 treatment attenuated all these to control levels. In addition, Ang II-induced enhanced levels of thiobarbituric acid-reactive substances (TBARS) and protein carbonyl content were also attenuated toward control levels by C-ANP 4-23 treatment. On the other hand, Ang II inhibited the levels of nitric oxide (NO) and augmented the levels of peroxynitrite (OONO - ) in VSMC which were restored to control levels by C-ANP 4-23 treatment. Furthermore, C-ANP 4-23 treatment attenuated Ang II-induced enhanced expression of Giα proteins, phosphorylation of p38, JNK, and ERK 1,2 as well as hyperproliferation of VSMC as determined by DNA synthesis, and metabolic activity. These results indicate that C-ANP 4-23 , via the activation of NPR-C, attenuates Ang II-induced enhanced nitroxidative stress, overexpression of Giα proteins, increased activation of the p38/JNK/ERK 1,2 signaling pathways, and hyperproliferation of VSMC. It may be suggested that C-ANP 4-23 could be used as a therapeutic agent in the treatment of vascular remodeling associated with hypertension and atherosclerosis.

Identification and characterization of [6]-shogaol from ginger as inhibitor of vascular smooth muscle cell proliferation.

Science.gov (United States)

Liu, Rongxia; Heiss, Elke H; Sider, Nadine; Schinkovitz, Andreas; Gröblacher, Barbara; Guo, Dean; Bucar, Franz; Bauer, Rudolf; Dirsch, Verena M; Atanasov, Atanas G

2015-05-01

Vascular smooth muscle cell (VSMC) proliferation is involved in the pathogenesis of cardiovascular disease, making the identification of new counteracting agents and their mechanisms of action relevant. Ginger and its constituents have been reported to improve cardiovascular health, but no studies exist addressing a potential interference with VSMC proliferation. The dichloromethane extract of ginger inhibited VSMC proliferation when monitored by resazurin metabolic conversion (IC50 = 2.5 μg/mL). The examination of major constituents from ginger yielded [6]-shogaol as the most active compound (IC50 = 2.7 μM). In the tested concentration range [6]-shogaol did not exhibit cytotoxicity toward VSMC and did not interfere with endothelial cell proliferation. [6]-shogaol inhibited DNA synthesis and induced accumulation of the VSMC in the G0 /G1 cell-cycle phase accompanied with activation of the nuclear factor-erythroid 2-related factor 2 (Nrf2)/HO-1 pathway. Since [6]-shogaol lost its antiproliferative activity in the presence of the heme oxygenase-1 (HO-1) inhibitor tin protoporphyrin IX, HO-1 induction appears to contribute to the antiproliferative effect. This study demonstrates for the first time inhibitory potential of ginger constituents on VSMC proliferation. The presented data suggest that [6]-shogaol exerts its antiproliferative effect through accumulation of cells in the G0 /G1 cell-cycle phase associated with activation of the Nrf2/HO-1 pathway. © 2015 The Authors. Molecular Nutrition & Food Research published by Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Vascular nitric oxide: Beyond eNOS

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Yingzi Zhao

2015-10-01

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

Stimulation of aortic smooth muscle cell mitogenesis by serotonin

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