Effect of N-Acetyl-L-Cysteine and alpha-Tocopherol Administration on Endogenous Antioxidant Protection of Liver DNA and RNA and plasma Lipid Profile in gamma-Irradiated Rats

The present study wasundertaken to evaluate the combined antioxidative capacity of N-acetyl-L-cysteine (NAC, 120 mg/100g b. wt) and alpha tocopherol (10mg/100g b. wt.) injected intra peritoneally one h before irradiation of male rats. Whole body gamma irradiation (2Gy) induced significant elevation in liver DNA and significant drop in liver protein content, while liver RNA showed no significant changes. Triglycerides and LDL-cholesterol elevated significantly after irradiation, whereas no significant changes were observed in total cholesterol, while HDL-cholesterol significantly decreased. Blood and liver glutathione were significantly decreased, whereas plasma MDA was significantly increased. NAC and alpha-tocopherol injection elevated RNA and blood glutathione levels compared to control and depressed total cholesterol and LDL-cholesterol levels, as well as MDA in the liver. The combined treatment prior to irradiation decreased DNA, elevated RNA and normalized liver protein content. Triglycerides were decreased after 1 and 3 days and total cholesterol dropped significantly on the 1st and 7th days. LDL was ameliorated while HDL was significantly declined then elevated after 7 days. Blood glutathione was normalized while liver glutathione was significantly elevated and MDA was reduced both in liver and plasma. This combined treatment has proven to be recommended to enhance the natural defenses against deleterious effects of oxidative stress