radioprotective efficiency of combined administration of natural antioxidants [rutin and vitamin e] and a sulfhydryl compound in irradiated rats

ABSTRACT

In the present study, the radioprotective effects of natural antioxidants, rutin alone, vitamin E alone or both of them combined with a synthetic radioprotector, cysteine, have been investigated in irradiated rats. Furthermore, the oxidative stress biomarkers and certain liver function tests of the whole body irradiated rats were examined. The effect of irradiation was evaluated by exposing the whole body of rats to gamma radiation at acute single dose of 6.5 Gy. Rutin [1.064 mmol/kg] was daily administered orally for two weeks before irradiation, vitamin E [50 mg/100g] was injected intraperitoneally daily for seven days before irradiation, while, cysteine [30 mg/kg] was intra-peritoneally administered 30 mm. only before irradiation. Blood and liver malondialdehyde [MDA], glutathione [GSH] and plasma superoxide dismutase [SOD] levels were evaluated. Serum aspartate aminotransferase [AST], alanine aminotransferase [ALT] and alkaline phosphatase [ALP] activities were also measured in various groups. The data revealed deleterious damage of radiation exposure which was manifested as a significant increase in lipid peroxidation measured as MDA. On the other hand, the activity of SOD and the level of GSH were reduced after irradiation. In addition, the activities of serum ALP, AST and ALT were markedly elevated after radiation exposure. Administration of rutin or vitamin E alone or combined with cysteine before radiation provided a protective effect as measured by the tested parameters. It could be concluded that treatment with the natural antioxidants can control radiation-induced oxidative damage in the biological system. This study indicates that the use of combination of agents is a promising approach for maximizing radioprotection with minimal adverse effects. Administration of cysteine iucreases the radioprotective effects of rutin and vitamin E against the damaging effects of ionizing radiation