Effects of four oxidants, menadione, 1-chloro-2,4-dinitrobenzene, hydrogen peroxide and cumene hydroperoxide, on fission yeast Schizosaccharmoyces pombe

Several chemical agents have been used to exert oxidative stress in the study of stress response, but differences in the effects of different reagents have received little attention. To elucidate whether such differences exist, the response of Schizosaccharomyces pombe to menadione (MD), 1-chloro-2,4-dinitrobenzene (CDNB), hydrogen peroxide and cumene hydroperoxide (CHP), which are frequently used to exert oxidative stress, was investigated. Sensitivity to these reagents differed among mutants deficient in genes involved in oxidative stress resistance. N-Acetylcysteine restored resistance to MD, CHP and hydrogen peroxide but did not change sensitivity to CDNB. The induction kinetics of genes induced by oxidative stress differed for each reagent. MD, CDNB and hydrogen peroxide caused a transient induction of genes, but the peak times of induction differed among the reagents. CHP gave quite different kinetics in that the induction continued for up to 2 h. The ctt1(+) gene was not induced by CHP. GSH rapidly decreased in the cells treated with high concentrations of these reagents, but at a low concentration only CDNB decreased GSH. These results indicated that S. pombe responded differently to the oxidative stress exerted by these different reagents.