AQUEOUS EXTRACTS OF CIGARETTE-SMOKE PROMOTE THE OXIDATION OF LOW-DENSITY-LIPOPROTEIN BY PEROXIDASES

Oxidation of low density lipoprotein (LDL) by cigarette smoke has been considered a potential mechanism by which smoking may promote atheros clerosis, We report in this study that cigarette smoke extract (CSE) i nhibited copper-induced oxidation of LDL suggesting the presence of an tioxidants in CSE, It is currently believed that peroxidases may oxidi ze LDL in vivo and during such oxidations antioxidants become pro-oxid ants. Accordingly, when LDL mas oxidized by peroxidase in the presence of CSE there was an increase in the oxidation of LDL, This is the fir st study suggesting that smoking may promote atherosclerosis by enhanc ing peroxidase-catalyzed lipid peroxidation. (C) 1997 Federation of Eu ropean Biochemical Societies.