REACTIVE OXYGEN SPECIES INDUCE APOPTOSIS OF VASCULAR SMOOTH-MUSCLE CELL

Apoptosis of vascular smooth muscle cell (VSMC) plays an important rol e in the genesis of atherosclerosis and restenosis. In order to invest igate the role of reactive oxygen species in the induction of VSMC apo ptosis, rat VSMCs were treated with glucose oxidase/glucose (GO/G) or diethylmaleate (DEM). The results showed that GO/G and DEM led to VSMC death. Administration of catalase, superoxide dismutase and deferoxam ine revealed that H2O2 was the major reactive oxygen species causing c ell death, and H2O2O exerted its effect by formation of hydroxyl radic al ((OH)-O-.). GO/G- and DEM-induced VSMC death occurred by apoptosis characterized by ''DNA ladders'', condensation of nuclei, positive to in situ nick-end labeling and increases in histone-associated DNA frag mentation. This study suggests that H2O2 and its derived form (OH)-O-. might be related to apoptosis of VSMC in atherosclerosis and restenos is. (C) 1997 Federation of European Biochemical Societies.