Role of germanium L-cysteine α-tocopherol complex as stimulator of some antioxidant defense systems in gamma-irradiated rats

This study was conducted to evaluate the potency of the newly prepared germanium L-cysteine α-tocopherol complex [germanium dichloro tetrakis (L-cysteinyl-α-tocopherol amide) dichloride] as a protective agent against γ-irradiation-induced free radicals production and liver toxicity. Male Swiss albino rats were injected intraperitoneally with the germanium complex in a concentration of 75 mg kg^-1 body mass per dose, for 6 successive doses, last dose administered twenty minutes pre-exposure to a single dose of whole body γ-irradiation of 6.5 Gy. Lipid peroxidation (LPx), nitric oxide (NO), glutathione (GSH) levels, and activity of the antioxidant enzymes glutathione peroxidase (GPx), superoxide dismutase (SOD), and catalase (CAT) were estimated in blood and liver. Blood total protein, cholesterol, triglyceride and α-tocopherol content were estimated as well. The results revealed that administration of germanium complex pre-irradiation resulted in significant (p < 0.001) improvement compared to the irradiated group in the level of hepatic and blood LPx. Hepatic GSH revealed a significant increase (p < 0.001), while its level showed no significant variation in blood. Also, the level of NO in blood and liver increased significantly (p < 0.001). On the other hand, pretreatment with the germanium complex normalized the activities of SOD, GPx and CAT in blood and liver when compared to the irradiated group. The study also documents a marked decrease in a blood triglyceride and cholesterol (p < 0.001) and a significant increase (p < 0.001) of α-tocopherol and total protein contents in blood. These biochemical changes were associated with marked improvement of histological status. Therefore, the germanium L-cysteine α-tocopherol complex may be a good candidate for ameliorating the changes induced by irradiation, which indicates the beneficial radio-protective role of this antioxidant agent.