|
|
||||||||
Department of Physiology and Biophysics, University of Mississippi Medical Center, Jackson, Mississippi 39216
Dynamic changes in the reduction-oxidation (redox) state of the tissue lead to the pathophysiological condition. Reduced homocysteine causes dysfunctions in endothelium. The proliferation of smooth muscle cells may lead to occlusive vascular disease, ischemia, and heart failure, but whether fibrosis and hypertension are a consequence of smooth muscle proliferation is unclear. Redox changes during hyperhomocyst(e)inemia may be one of the causes of premature atherosclerotic heart disease. To examine the effect of homocystine on human vascular smooth muscle cells (HVSMC), we isolated HVSMC from idiopathic dilated cardiomyopathic hearts. Coronaries in these hearts were apparently normal. HVSMC numbers in culture were measured by hemocytometer in the presence and absence of homocystine. Results show that homocystine induced cellular proliferation. This proliferation was reversed by the addition of the antioxidant N-acetylcysteine (NAC). Homocystine induces collagen expression in a dose- and time-dependent manner, as measured by Northern blot (mRNA) analysis. The 50% inhibitory concentration of 5 µM for collagen was estimated. The induction of collagen was reversed by the addition of NAC and reduced glutathione. To localize the receptor for homocystine on HVSMC, we synthesized fluorescamine-labeled homocystine conjugate. Incubation of labeled homocystine with HVSMC demonstrated membrane and cytosol localization of homocystine binding. The receptor-ligand binding was disrupted by NAC. Based on sodium dodecyl sulfate-polyacrylamide gel electrophoresis fluorography, we observed a 40- to 25-kDa homocystine redox receptor in HVSMC. Our results suggested that the redox homocysteine induces HVSMC proliferation by binding to the redox receptor and may exacerbate atherosclerotic lesion formation by inducing collagen expression.
collagen; actin; vascular occlusive disease; gene expression; signal transduction; vascular remodeling
This article has been cited by other articles:
![]() |
R. Rodrigo, W. Passalacqua, J. Araya, M. Orellana, and G. Rivera Homocysteine and Essential Hypertension J. Clin. Pharmacol., December 1, 2003; 43(12): 1299 - 1306. [Abstract] [Full Text] [PDF] |
||||
![]() |
H. S. Sood, M. J. Hunt, and S. C. Tyagi Peroxisome proliferator ameliorates endothelial dysfunction in a murine model of hyperhomocysteinemia Am J Physiol Lung Cell Mol Physiol, February 1, 2003; 284(2): L333 - L341. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. J. Hunt and S. C. Tyagi Peroxisome proliferators compete and ameliorate Hcy-mediated endocardial endothelial cell activation Am J Physiol Cell Physiol, October 1, 2002; 283(4): C1073 - C1079. [Abstract] [Full Text] [PDF] |
||||
![]() |
H. TSUKAMOTO and S. C. LU Current concepts in the pathogenesis of alcoholic liver injury FASEB J, June 1, 2001; 15(8): 1335 - 1349. [Abstract] [Full Text] [PDF] |
||||
![]() |
E. G. J. Vermeulen, H. W. M. Niessen, M. Bogels, C. D. A. Stehouwer, J. A. Rauwerda, and V. W. M. van Hinsbergh Decreased Smooth Muscle Cell/Extracellular Matrix Ratio of Media of Femoral Artery in Patients With Atherosclerosis and Hyperhomocysteinemia Arterioscler. Thromb. Vasc. Biol., April 1, 2001; 21(4): 573 - 577. [Abstract] [Full Text] [PDF] |
||||
![]() |
Y. Saso, E. M. Conner, B. R. Teegarden, and C.-S. Yuan S-Adenosyl-L-homocysteine Hydrolase Inhibitor Mediates Immunosuppressive Effects in Vivo: Suppression of Delayed Type Hypersensitivity Ear Swelling and Peptidoglycan Polysaccharide-Induced Arthritis J. Pharmacol. Exp. Ther., January 1, 2001; 296(1): 106 - 112. [Abstract] [Full Text] |
||||
![]() |
T. H. ROSENQUIST, A. M. SCHNEIDER, and D. T. MONAGHAN N-methyl-D-aspartate receptor agonists modulate homocysteine-induced developmental abnormalities FASEB J, September 1, 1999; 13(12): 1523 - 1531. [Abstract] [Full Text] |
||||
![]() |
V. S. Mujumdar, C. M. Tummalapalli, G. M. Aru, and S. C. Tyagi Mechanism of constrictive vascular remodeling by homocysteine: role of PPAR Am J Physiol Cell Physiol, May 1, 2002; 282(5): C1009 - C1015. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |