Antioxidative effect of ursodeoxycholic acid in the liver of rats with oxidative stress caused by gamma-irradiation

We studied effects of ursodeoxycholic acid (UDCA) (10 and 100 mg/kg b.w.) on the free radical generation, lipid peroxidation and the antioxidant defense system in the liver of rats with oxidative stress caused by gamma-irradiation. Both doses of UDCA normalized the liver parameters enhanced by gamma-irradiation: the content of superoxide anion and carbonyl-containing products of lipid peroxidation (alkanals, alkenals, alkadienals and ketones), the superoxide dismutase activity and the chemiluminescence enhanced by luminol. Only the highest dose of UDCA (100 mg/kg b.w.) decreased the chemiluminescence enhanced by lucigenin in liver microsomes and the hydroxyalkenals content in the liver. UDCA prevented reduced glutathione depletion caused by gamma-irradiation, whereas glutathione-related enzyme activities did not change under the influence of both the UDCA doses as well as gamma-irradiation. Thus, the data obtained suggest that UDCA is a metabolite having the sufficiently effective antioxidant properties.