Beneficial effects of spin-labelled nitrosourea on CCNU-induced oxidative stress in rat blood compared with vitamin E.

This study was carried out to determine the effects of a recently synthesized 1-ethyl-3-[4-(2,2,6,6-tetra-methylpiperidine-1-oxyl)]-1-nitrosourea (SLENU), compared with vitamin E as a positive control, on 1-(2-chloroethyl)-3-cyclohexyl-1-nitrosourea (CCNU)-induced oxidative stress in rats. We determined plasma malonyl dialdehyde (MDA) levels and the activities of erythrocyte superoxide dismutase (SOD) and catalase (CAT). Forty two white albino healthy rats were treated once daily for 30 days with oral preparations of CCNU (12.5 mg/kg and 25 mg/kg), SLENU (25-200 mg/kg), and combinations of these. The CCNU-induced increase in plasma MDA level and the usual decrease in erythrocyte SOD and CAT activities were reversed by SLENU, but not by vitamin E. We have previously demonstrated that SLENU is a superoxide scavenger. A combination of our present findings with previous results thus leads us to proposing a new chemotherapeutic combination of CCNU and SLENU that is devoid of high toxicity.