Elevation of antioxidants in the kidneys of mice by low-dose irradiation and its effect on Fe³⁺–NTA-induced kidney damage

We previously examined the effects of 0.5 Gy of γ- or X-irradiation on endogenous antioxidative materials, including glutathione, glutathione-related enzymes, superoxide dismutase and catalase in the liver, pancreas and brain of mice. An increase in the antioxidants was observed soon after the irradiation. We also demonstrated that the low-dose irradiation gave suppressive effects on reactive oxygen species (ROS)-related disease models such as acute hepatitis, type I diabetes and Parkinson's disease. These results suggested that the suppression or inhibition of the ROS-related diseases were made through the elevation of the antioxidants. We studied the effects of irradiation (0.5 Gy of γ-ray) reducing the renal oxidative damage in Fe³⁺ nitrilotri-acetate (NTA) injected mice. We examined transaminase activity, lipid peroxide level and those levels of antioxidants in the mouse. Both transaminase activities and lipid peroxide level accelerated decrease to normal level by the irradiation. The levels of total glutathione content and the activities of its related enzymes were slightly increased in the irradiated group. On the other hand, catalase (CAT) activity was significantly increased by the irradiation. These findings suggested that low-dose irradiation relieved functional disorder in the kidney of mice with ROS-related diseases, probably through enhancing antioxidant, in particular CAT activity.