title: Suppression of vascular smooth muscle cell responses induced by TNF-α in GM3 synthase gene transfected cells.
abstract: The natural accumulation of ganglioside GM3 (N-glycolylneuraminic acid) on atherosclerotic lesions is a common theory. The present study is the first to examine the effects of the GM3 synthase gene on the responses of vascular smooth muscle cells (VSMC) to tumor necrosis factor-α (TNF-α). We found that overexpression of the GM3 synthase gene inhibited DNA synthesis and ERK1/2 activity induced by TNF-α in VSMC, whereas the basal levels of DNA synthesis and ERK1/2 activity remained unchanged. In addition, GM3 synthase gene transfectants significantly reduced the migration and invasion of VSMC following TNF-α treatment, compared with empty vector transfectants. Furthermore, TNF-α-induced matrix metalloproteinase-9 (MMP-9) expression and promoter activity were also decreased in GM3 synthase gene transfectants. GM3 synthase gene expression markedly suppressed the TNF-α-stimulated transcriptional activity of activator protein-1 (AP-1) and nuclear factor-κB (NF-κB), which are the controlling factors of MMP-9 expression. Consistent with these results, the addition of anti-GM3 antibody into the GM3 synthase gene transfectants blocked inhibition of DNA synthesis, ERK1/2 activity, migration and invasion. Finally, GM3 synthase gene transfectants treated with anti-GM3 antibody reversed the suppression of MMP-9 expression by reducing AP-1 and NF-κB binding activity. These results suggest regulatory roles for the GM3 synthase gene in VSMC proliferation and migration during the formation of atherosclerotic lesions.
authors.affiliation: Department of Food and Biotechnology, Chungju National University, Chungju, Chungbuk 380-702, South Korea.
authors.forename: Sung-Suk
authors.initials: SS
authors.lastname: Park
authors.forename: Wun-Jae
authors.initials: WJ
authors.lastname: Kim
authors.forename: Sung-Kwon
authors.initials: SK
authors.lastname: Moon
mesh_terms: D000818:Animals; D002465:Cell Movement; D049109:Cell Proliferation; D004789:Enzyme Activation; D006801:Humans; D008297:Male; D020780:Matrix Metalloproteinase 9 / Q000235:genetics / Q000378:metabolism; D051379:Mice; D019950:Mitogen-Activated Protein Kinase 1 / Q000378:metabolism; D048052:Mitogen-Activated Protein Kinase 3 / Q000378:metabolism; D009131:Muscle, Smooth, Vascular / Q000166:cytology*; D032389:Myocytes, Smooth Muscle / Q000166:cytology / Q000187:drug effects* / Q000502:physiology*; D051381:Rats; D012799:Sialyltransferases / Q000235:genetics*; D014162:Transfection; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology*
chemical_list: D014409:Tumor Necrosis Factor-alpha; D012799:Sialyltransferases; C021343:haematoside synthetase; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D020780:Matrix Metalloproteinase 9