Age-associated changes in antioxidants and antioxidative enzymes in rats

The antioxidative defence capacity was assessed in tissues from different groups of rats at 3, 12 and 24 months of age. It was observed that the levels of antioxidants, vitamin E and ascorbic acid decreased in serum without any changes in liver; whereas reduced glutathione showed lower levels in both serum and liver with advancing age. Antioxidative enzymes such as superoxide dismutase and catalase activities did not indicate appreciable changes in hepatic mitochondria, but were observed to point out divergent trends in post-mitochondrial supernatants, superoxide dismutase showed reduced activities and catalase activities enhanced with age.