Oxysterols Induced Apoptosis in Cultured Smooth Muscle Cells through CPP32 Protease Activation and bcl-2 Protein Downregulation
Authors: Nishio, E.; Watanabe, Y.
Source: Biochemical and Biophysical Research Communications, Volume 226, Number 3, September 1996 , pp. 928-934(7)
Publisher: Academic Press
Abstract:Previously we have shown that oxidized low density lipoprotein (Ox-LDL) induced apoptosis in vascular smooth muscle cells (VSMCs) and that this apoptosis contributed to oxysterol, 7-ketocholesterol. The aim in this present study was to identify the mechanism by which oxysterols induced apoptosis in VSMCs. We show that both 7-ketocholesterol and 25-hydroxycholesterol induced apoptosis, followed by a rapid decrease in bcl-2 protein in the cells. CPP32 / Yamma inhibitor prevented apoptosis induced by 7-ketocholesterol and 25-hydroxycholesterol in VSMCs, whereas the exogenous cholesterol, which itself did not have any apoptotic activity, inhibited 25-hydroxycholesterol induced apoptosis but the 7-ketocholesterol-induced apoptosis was not affected. These results suggest that 25-hydroxycholesterol induced-apoptosis occurs by a different mechanism than 7-ketocholesterol induced-apoptosis.
Document Type: Research Article
Affiliations: Department of Pharmacology, National Defense Medical College, 3-2, Namiki, Tokorozawa, Saitama, 359, Japan
Publication date: September 1, 1996