IN-VITRO INHIBITION OF CATALASE ACTIVITY BY CIGARETTE-SMOKE - RELEVANCE FOR OXIDATIVE STRESS

The in vitro effects of cigarette smoke on catalase activity were inve stigated in biological preparations from rat liver and brain using a p olarographic method. In both cases cigarette smoke solutions showed a potent ability to inhibit catalase activity with a slight time depende ncy. The reversibility of their inhibitory activity was demonstrated b y in vitro dialysis tests. The catalase inhibitory compound(s) are for med in the smoking process, are not extracted with organic solvents an d appear to have a relatively low molecular weight. We also examined t he effects obtained by using two different commercial blends of tobacc o, achieving a major inhibition with Burley tobacco in comparison to B right tobacco, These data suggest that the cytotoxic and mutagenic eff ects of cigarette smoke may be mediated by its additional capacity to enhance the generation of free radicals by inhibiting catalase activit y, thus contributing to cell damage particularly during oxidative stre ss. (C) 1998 John Wiley & Sons, Ltd.