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Pathak AS, Stouffer GA. Differential responses to thrombospondin-1 and PDGF-BB in smooth muscle cells from atherosclerotic coronary arteries and internal thoracic arteries. Sci Rep 2024; 14:15847. [PMID: 38982274 PMCID: PMC11233497 DOI: 10.1038/s41598-024-66860-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2023] [Accepted: 07/04/2024] [Indexed: 07/11/2024] Open
Abstract
Atherosclerosis is rare in internal thoracic arteries (ITA) even in patients with severe atherosclerotic coronary artery (ACA) disease. To explore cellular differences, ITA SMC from 3 distinct donors and ACA SMC from 3 distinct donors were grown to sub-confluence and growth arrested for 48 h. Proliferation and thrombospondin-1 (TSP1) production were determined using standard techniques. ITA SMC were larger, grew more slowly and survived more passages than ACA SMC. ACA SMC had a more pronounced proliferative response to 10% serum than ITA SMC. Both ACA SMC and ITA SMC proliferated in response to exogenous TSP1 (12.5 µg/ml and 25 µg/ml) and platelet derived growth factor-BB (PDGF-BB; 20 ng/ml) but TSP1- and PDGF-BB-induced proliferation were partially inhibited by anti-TSP1 antibody A4.1, microRNA-21(miR-21)-3p inhibitors and miR-21-5p inhibitors in each of the 3 ACA SMC lines, but not in any of the ITA SMC lines. PDGF-BB stimulated TSP1 production in ACA SMC but not in ITA SMC but there was no increase in TSP1 levels in conditioned media in either SMC type. In summary, there are significant differences in morphology, proliferative capacity and in responses to TSP1 and PDGF-BB in SMC derived from ITA compared to SMC derived from ACA.
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Affiliation(s)
- Alokkumar S Pathak
- Division of Cardiology and McAllister Heart Institute, University of North Carolina, Chapel Hill, NC, 27599-7075, USA
| | - George A Stouffer
- Division of Cardiology and McAllister Heart Institute, University of North Carolina, Chapel Hill, NC, 27599-7075, USA.
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2
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Tang Y, Zhou X, Cao T, Chen E, Li Y, Lei W, Hu Y, He B, Liu S. Endoplasmic Reticulum Stress and Oxidative Stress in Inflammatory Diseases. DNA Cell Biol 2022; 41:924-934. [DOI: 10.1089/dna.2022.0353] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- Yun Tang
- Department of Clinical Laboratory Medicine, Institution of Microbiology and Infectious Diseases, The First Affiliated Hospital, Hengyang Medical School, University of South China, Hengyang, Hunan, China
| | - Xiangping Zhou
- Department of Clinical Laboratory Medicine, Institution of Microbiology and Infectious Diseases, The First Affiliated Hospital, Hengyang Medical School, University of South China, Hengyang, Hunan, China
| | - Ting Cao
- Department of Clinical Laboratory Medicine, Institution of Microbiology and Infectious Diseases, The First Affiliated Hospital, Hengyang Medical School, University of South China, Hengyang, Hunan, China
| | - En Chen
- Department of Clinical Laboratory Medicine, Institution of Microbiology and Infectious Diseases, The First Affiliated Hospital, Hengyang Medical School, University of South China, Hengyang, Hunan, China
| | - Yumeng Li
- Department of Clinical Laboratory Medicine, Institution of Microbiology and Infectious Diseases, The First Affiliated Hospital, Hengyang Medical School, University of South China, Hengyang, Hunan, China
| | - Wenbo Lei
- Department of Clinical Laboratory Medicine, Institution of Microbiology and Infectious Diseases, The First Affiliated Hospital, Hengyang Medical School, University of South China, Hengyang, Hunan, China
| | - Yibao Hu
- Department of Clinical Laboratory Medicine, Institution of Microbiology and Infectious Diseases, The First Affiliated Hospital, Hengyang Medical School, University of South China, Hengyang, Hunan, China
| | - Bisha He
- Department of Clinical Laboratory Medicine, Institution of Microbiology and Infectious Diseases, The First Affiliated Hospital, Hengyang Medical School, University of South China, Hengyang, Hunan, China
| | - Shuangquan Liu
- Department of Clinical Laboratory Medicine, Institution of Microbiology and Infectious Diseases, The First Affiliated Hospital, Hengyang Medical School, University of South China, Hengyang, Hunan, China
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Jain T, Nikolopoulou EA, Xu Q, Qu A. Hypoxia inducible factor as a therapeutic target for atherosclerosis. Pharmacol Ther 2018; 183:22-33. [DOI: 10.1016/j.pharmthera.2017.09.003] [Citation(s) in RCA: 77] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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Birthare K, Shojaee M, Jones CG, Brenner JR, Bashur CA. Collagen incorporation within electrospun conduits reduces lipid oxidation and impacts conduit mechanics. Biomed Mater 2016; 11:025019. [DOI: 10.1088/1748-6041/11/2/025019] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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Nguyen TU, Bashur CA, Kishore V. Impact of elastin incorporation into electrochemically aligned collagen fibers on mechanical properties and smooth muscle cell phenotype. Biomed Mater 2016; 11:025008. [PMID: 26987364 DOI: 10.1088/1748-6041/11/2/025008] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Application of tissue-engineered vascular grafts (TEVGs) for the replacement of small-diameter arteries is limited due to thrombosis and intimal hyperplasia. Previous studies have attempted to address the limitations of TEVGs by developing scaffolds that mimic the composition (collagen and elastin) of native arteries to better match the mechanical properties of the graft with the native tissue. However, most existing scaffolds do not recapitulate the aligned topography of the collagen fibers found in native vessels. In the current study, based on the principles of isoelectric focusing, two different types of elastin (soluble and insoluble) were incorporated into highly oriented electrochemically aligned collagen (ELAC) fibers and the effect of elastin incorporation on the mechanical properties of the ELAC fibers and smooth muscle cell (SMC) phenotype was investigated. The results indicate that elastin incorporation significantly decreased the modulus of ELAC fibers to converge upon that of native vessels. Further, a significant increase in yield strain and decrease in Young's modulus was observed on all fibers post SMC culture compared with before the culture. Real-time polymerase chain reaction results showed a significant increase in the expression of α-smooth muscle actin and calponin on ELAC fibers with insoluble elastin, suggesting that incorporation of insoluble elastin induces a contractile phenotype in SMCs after two weeks of culture on ELAC fibers. Immunofluorescence results showed that calponin expression increased with time on all fibers. In conclusion, insoluble elastin incorporated ELAC fibers have the potential to be used for the development of functional TEVGs for the repair and replacement of small-diameter arteries.
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Affiliation(s)
- Thuy-Uyen Nguyen
- Department of Chemical Engineering, Florida Institute of Technology, Melbourne, FL 32901, USA
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Green DE, Kang BY, Murphy TC, Hart CM. Peroxisome proliferator-activated receptor gamma (PPARγ) regulates thrombospondin-1 and Nox4 expression in hypoxia-induced human pulmonary artery smooth muscle cell proliferation. Pulm Circ 2013; 2:483-91. [PMID: 23372933 PMCID: PMC3555419 DOI: 10.4103/2045-8932.105037] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Transforming growth factor-β1 (TGF- β1) and thrombospondin-1 (TSP-1) are hypoxia-responsive mitogens that promote vascular smooth muscle cell (SMC) proliferation, a critical event in the pathogenesis of pulmonary hypertension (PH). We previously demonstrated that hypoxia-induced human pulmonary artery smooth muscle (HPASMC) cell proliferation and expression of the NADPH oxidase subunit, Nox4, were attenuated by the peroxisome proliferator-activated receptor γ (PPARγ) agonist, rosiglitazone. The current study examines the hypothesis that rosiglitazone regulates Nox4 expression and HPASMC proliferation by attenuating TSP-1 signaling. Selected HPASMC were exposed to normoxic or hypoxic (1% O2) environments or TSP-1 (0-1 μg/ ml) for 72 hours ± administration of rosiglitazone (10 μM). Cellular proliferation, Nox4, TSP-1, and TGF-β1 expression and reactive oxygen species generation were measured. Mice exposed to hypoxia (10% O2) for three weeks were treated with rosiglitazone (10 mg/kg/day) for the final 10 days, and lung TSP-1 expression was examined. Hypoxia increased TSP-1 and TGF-β1 expression and HPASMC proliferation, and neutralizing antibodies to TSP-1 or TGF-β1 attenuated proliferation. Rosiglitazone attenuated hypoxia-induced HPASMC proliferation and increases in mouse lung and HPASMC TSP-1 expression, but failed to reduce increases in TGF-β1 expression or Nox4 expression and activity caused by direct TSP-1 stimulation. Transfecting HPASMC with siRNA to Nox4 attenuated hypoxia- or TSP-1-stimulated HPASMC proliferation. These findings provide novel evidence that TSP-1-mediated Nox4 expression plays a critical role in hypoxia-induced HPASMC proliferation. PPARγ activation with exogenous ligands attenuates TSP-1 expression to reduce Nox4 expression. These results clarify mechanisms of hypoxia-induced SMC proliferation and suggest additional pathways by which PPARγ agonists may regulate critical steps in the pathobiology of PH.
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Affiliation(s)
- David E Green
- Department of Medicine, Emory University, Atlanta Veterans Affairs Medical Center, Decatur, Georgia, USA
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Venkatraman L, Chia SM, Narmada B, White J, Bhowmick S, Forbes Dewey C, So P, Tucker-Kellogg L, Yu H. Plasmin triggers a switch-like decrease in thrombospondin-dependent activation of TGF-β1. Biophys J 2012; 103:1060-8. [PMID: 23009856 PMCID: PMC3433618 DOI: 10.1016/j.bpj.2012.06.050] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2011] [Revised: 06/24/2012] [Accepted: 06/28/2012] [Indexed: 01/13/2023] Open
Abstract
Transforming growth factor-β1 (TGF-β1) is a potent regulator of extracellular matrix production, wound healing, differentiation, and immune response, and is implicated in the progression of fibrotic diseases and cancer. Extracellular activation of TGF-β1 from its latent form provides spatiotemporal control over TGF-β1 signaling, but the current understanding of TGF-β1 activation does not emphasize cross talk between activators. Plasmin (PLS) and thrombospondin-1 (TSP1) have been studied individually as activators of TGF-β1, and in this work we used a systems-level approach with mathematical modeling and in vitro experiments to study the interplay between PLS and TSP1 in TGF-β1 activation. Simulations and steady-state analysis predicted a switch-like bistable transition between two levels of active TGF-β1, with an inverse correlation between PLS and TSP1. In particular, the model predicted that increasing PLS breaks a TSP1-TGF-β1 positive feedback loop and causes an unexpected net decrease in TGF-β1 activation. To test these predictions in vitro, we treated rat hepatocytes and hepatic stellate cells with PLS, which caused proteolytic cleavage of TSP1 and decreased activation of TGF-β1. The TGF-β1 activation levels showed a cooperative dose response, and a test of hysteresis in the cocultured cells validated that TGF-β1 activation is bistable. We conclude that switch-like behavior arises from natural competition between two distinct modes of TGF-β1 activation: a TSP1-mediated mode of high activation and a PLS-mediated mode of low activation. This switch suggests an explanation for the unexpected effects of the plasminogen activation system on TGF-β1 in fibrotic diseases in vivo, as well as novel prognostic and therapeutic approaches for diseases with TGF-β dysregulation.
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Affiliation(s)
- Lakshmi Venkatraman
- Singapore-MIT Alliance, Computational Systems Biology Programme, Singapore
- School of Computer Engineering, Nanyang Technological University, Singapore
| | - Ser-Mien Chia
- Singapore-MIT Alliance, Computational Systems Biology Programme, Singapore
| | | | - Jacob K. White
- Singapore-MIT Alliance, Computational Systems Biology Programme, Singapore
- Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, Massachusetts
| | - Sourav S. Bhowmick
- Singapore-MIT Alliance, Computational Systems Biology Programme, Singapore
- School of Computer Engineering, Nanyang Technological University, Singapore
| | - C. Forbes Dewey
- Singapore-MIT Alliance, Computational Systems Biology Programme, Singapore
- Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts
| | - Peter T. So
- Singapore-MIT Alliance, Computational Systems Biology Programme, Singapore
- Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts
| | - Lisa Tucker-Kellogg
- Singapore-MIT Alliance, Computational Systems Biology Programme, Singapore
- Mechanobiology Institute, Temasek Laboratories, National University of Singapore, Singapore
| | - Hanry Yu
- Singapore-MIT Alliance, Computational Systems Biology Programme, Singapore
- NUS Graduate School for Integrative Sciences, Singapore
- Department of Physiology, Temasek Laboratories, National University of Singapore, Singapore
- Mechanobiology Institute, Temasek Laboratories, National University of Singapore, Singapore
- Institute of Bioengineering and Nanotechnology, ASTAR, Singapore
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Bashur CA, Ramamurthi A. Aligned electrospun scaffolds and elastogenic factors for vascular cell-mediated elastic matrix assembly. J Tissue Eng Regen Med 2011; 6:673-86. [PMID: 21953981 DOI: 10.1002/term.470] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2011] [Revised: 04/16/2011] [Accepted: 07/05/2011] [Indexed: 12/24/2022]
Abstract
Strategies to enhance the production of organized elastic matrix by smooth muscle cells (SMCs) are critical in engineering functional vascular conduits. Therefore, the goal of this study was to determine the effect of different surfaces, i.e. random and aligned electrospun poly(ε-caprolactone) meshes and two-dimensional (2D) controls, and exogenous elastogenic factors on the cultured rat aortic SMC phenotype and production of extracellular matrix. This study demonstrated that aligned electrospun fibres guide cell alignment, induce a more elongated cell morphology and promote a more synthetic phenotype. Importantly, these cells produced greater amounts of elastin-rich matrix per cell on the electrospun scaffolds. In addition, exogenous elastogenic factors severely limited rat aortic smooth muscle cells (RASMCs) proliferation and promoted a more synthetic SMC phenotype on electrospun meshes, but they had less effect on 2D controls. Finally, the elastogenic factors induced the SMCs to generate more matrix collagen and elastin on a per cell basis. Together, these results demonstrate the elastogenic benefits of electrospun meshes.
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Affiliation(s)
- Chris A Bashur
- Department of Biomedical Engineering, Cleveland Clinic, Cleveland, OH, USA
| | - Anand Ramamurthi
- Department of Biomedical Engineering, Cleveland Clinic, Cleveland, OH, USA.,Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, USA.,Department of Bioengineering, Clemson University, Clemson, SC, USA
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Pathak A, Zhao R, Huang J, Stouffer GA. Eptifibatide and abciximab inhibit insulin-induced focal adhesion formation and proliferative responses in human aortic smooth muscle cells. Cardiovasc Diabetol 2008; 7:36. [PMID: 19108709 PMCID: PMC2628888 DOI: 10.1186/1475-2840-7-36] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/16/2008] [Accepted: 12/23/2008] [Indexed: 01/08/2023] Open
Abstract
Background The use of abciximab (c7E3 Fab) or eptifibatide improves clinical outcomes in diabetics undergoing percutaneous coronary intervention. These β3 integrin inhibitors antagonize fibrinogen binding to αIIbβ3 integrins on platelets and ligand binding to αvβ3 integrins on vascular cells. αvβ3 integrins influence responses to insulin in various cell types but effects in human aortic smooth muscle cells (HASMC) are unknown. Results and discussion Insulin elicited a dose-dependent proliferative response in HASMC. Pretreatment with m7E3 (an anti-β3 integrin monoclonal antibody from which abciximab is derived), c7E3 or LM609 inhibited proliferative responses to insulin by 81%, 59% and 28%, respectively. Eptifibatide or cyclic RGD peptides completely abolished insulin-induced proliferation whereas tirofiban, which binds αIIbβ3 but not αvβ3, had no effect. Insulin-induced increases in c-Jun NH2-terminal kinase-1 (JNK1) activity were partially inhibited by m7E3 and eptifibatide whereas antagonism of αvβ3 integrins had no effect on insulin-induced increases in extracellular signal-regulated kinase (ERK) activity. Insulin stimulated a rapid increase in the number of vinculin-containing focal adhesions per cell and treatment with m7E3, c7E3 or eptifibatide inhibited insulin-induced increases in focal adhesions by 100%, 74% and 73%, respectively. Conclusion These results demonstrate that αvβ3 antagonists inhibit signaling, focal adhesion formation and proliferation of insulin-treated HASMC.
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Affiliation(s)
- Alokkumar Pathak
- Carolina Cardiovascular Biology Center, University of North Carolina, Chapel Hill, NC, USA.
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Pan D, Yang J, Lu F, Xu D, Zhou L, Shi A, Cao K. Platelet-derived growth factor BB modulates PCNA protein synthesis partially through the transforming growth factor beta signalling pathway in vascular smooth muscle cells. Biochem Cell Biol 2007; 85:606-15. [PMID: 17901902 DOI: 10.1139/o07-064] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
PDGF-BB (Platelet-derived growth factor BB) and TGF-β1(transforming growth factor β1) are important growth factors in the modulation of vascular smooth muscle cell (VSMC) proliferation and PCNA (proliferating cell nuclear antigen) expression in VSMCs. PCNA expresses at a high level in proliferating cells. The present study aims to assess the effects of PDGF-BB-induced overexpression of TGF-β1 on PCNA in VSMCs. The downstream proteins of the TGF-β signalling system in VSMCs, including TGF-β type I receptor (ALK-5 in VSMCs), Smurf2, Smad2, pSmad2/3, Smad4, and Smad7, were also investigated. Our results revealed that PDGF-BB significantly increased the expressions of TGF-β1 and PCNA, and the increase in PCNA can be partially inhibited by neutralizing anti-TGF-β1 antibody. Furthermore, PDGF-BB increased the expression of ALK-5, Smurf2, pSmad2/3, and Smad4, but lowered the levels of Smad2 and Smad7; these alterations were partially restored by neutralizing anti-TGF-β1 antibody. These findings suggest that PDGF-BB promotes PCNA expression in VSMCs partially through TGF-β1 overexpression, and that the TGF-β signalling system involves the molecular mechanism of PDGF-BB in VSMCs.
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Affiliation(s)
- Dabin Pan
- Department of Cardiology, First Affiliated Hospital of Nanjing Medical University, No. 300 Guangzhou Road, Nanjing 210029, PR, China
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Kahn MB, Boesze-Battaglia K, Stepp DW, Petrov A, Huang Y, Mason RP, Tulenko TN. Influence of serum cholesterol on atherogenesis and intimal hyperplasia after angioplasty: inhibition by amlodipine. Am J Physiol Heart Circ Physiol 2004; 288:H591-600. [PMID: 15388506 PMCID: PMC4732715 DOI: 10.1152/ajpheart.00617.2004] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The objectives of the present study were to determine whether serum hypercholesterolemia (HC) promotes the development of spontaneous and angioplasty-induced lesions and whether amlodipine inhibits these lesions and cellular processes underlying their genesis. Rabbits were fed normal, 0.5%, or 2% cholesterol diets for 9 wk, which resulted in the development of increasing HC. After week one, balloon dilation of the abdominal aorta was performed while the thoracic aorta was not disturbed and monitored for the development of spontaneous lesions. Lesion size increased with the degree of HC and was accompanied by increased collagen synthesis and smooth muscle cell (SMC) proliferation at each site. Amlodipine (5 mg/kg p.o.) inhibited lesion size by 50% (P < 0.01) at both sites in cholesterol-fed animals but not at angioplasty sites in animals on a normal diet. Local collagen synthesis was inhibited at both sites by amlodipine in the diet animals. The increase in HC was accompanied by a 1.7-fold increase in basal Ca2+ uptake in SMCs in the thoracic aorta, which was not altered by amlodipine, nifedipine, Ni2+, or La3+, revealing an uninhibitable calcium leak during atherogenesis. In culture, cholesterol enrichment increased SMC proliferation, collagen synthesis, and the secretion of a soluble SMC mitogen, which were inhibited by amlodipine (10(-9) M). Finally, in SMC membranes, amlodipine uniquely restored the cholesterol-expanded membrane bilayer width without any effect on membrane fluidity. This study establishes a causal role between serum HC and the development of spontaneous and angioplasty-induced lesions and the ability of amlodipine to disrupt this action by a novel remodelling action on the SMC membrane.
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Affiliation(s)
- Mark B Kahn
- Department of Surgery, Thomas Jefferson University College of Medicine, Philadelphia, Pennsylvania 19107, USA
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Sajid M, Zhao R, Pathak A, Smyth SS, Stouffer GA. Alphavbeta3-integrin antagonists inhibit thrombin-induced proliferation and focal adhesion formation in smooth muscle cells. Am J Physiol Cell Physiol 2003; 285:C1330-8. [PMID: 12878490 DOI: 10.1152/ajpcell.00475.2002] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Alphavbeta3-integrin antagonists reduced neointimal formation following vascular injury in eight different animal models. Because alpha-thrombin contributes to neointimal formation, we examined the hypothesis that alphavbeta3-integrins influence alpha-thrombin-induced signaling. Cultured rat aortic smooth muscle cells (RASMC) expressed alphavbeta3-integrins as demonstrated by immunofluorescence microscopy and fluorescence-activated cell sorting analysis. Proliferative responses to alpha-thrombin were partially inhibited by anti-beta3-integrin monoclonal antibody F11 and by cyclic RGD peptides. Immunofluorescence microscopy showed that alpha-thrombin stimulated a rapid increase in the formation of focal adhesions as identified by vinculin staining and that this effect was partially inhibited by alphavbeta3 antagonists. Beta3-integrin staining was diffuse in quiescent RASMC and did not concentrate at sites of focal adhesions following thrombin treatment. Alpha-thrombin elicited a time-dependent increase in activation of c-Jun NH2-terminal kinase-1 (JNK1) and in tyrosine phosphorylation of focal adhesion kinase (FAK). Alphavbeta3-integrin antagonists partially inhibited increases in JNK1 activity but had no effect on FAK phosphorylation. In SMC isolated from beta3-integrin-deficient mice, focal adhesion formation was impaired in response to thrombin but not sphingosine-1-phosphate, a potent activator of Rho. In summary, alphavbeta3-integrins play an important role in alpha-thrombin-induced proliferation and focal adhesion formation in RASMC.
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Affiliation(s)
- M Sajid
- Division of Cardiology, Carolina Cardiovascular Biology Center, University of North Carolina, Chapel Hill, NC 27599-7075, USA
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