Modification by vitamin E and exercise of oxidative stress in regions of aging rat brain: Studies on superoxide dismutase isoenzymes and protein oxidation status

This study was aimed at determining the effect of exercise and vitamin E on age-associated changes in the superoxide dismutase (SOD), lipid (LPO) and protein oxidations (PO) in the cerebral cortex (CC), cerebellum (CB) and hippocampus (HC) of rat brain. For this, male Wistar albino rats of 4- (adult), 12- (middle-age) and 18-month (old) of age were orally supplemented with vitamin E and swim trained at 3% intensity for 30 min/day, 5 days/week, and for a period of 30 days. Reduced total SOD was evident with age in the CC while it was highest in the HC of old rats. Vitamin E elevated SOD in the old trainees. Mn-SOD increased in the middle-age and old trainees and Cu Zn-SOD increased in the supplemented and trained adults. Age-related and region-specific increase in protein carbonyl (PrC) content with decreased sulphydryl (P-SH) was seen. Vitamin E reduced PrC and advanced oxidation of protein products (AOPP) in all ages, and appreciably in the HC and CB. Our study emphasizes a correlation between mitochondrial H2O2 generation, Mn-SOD activity and MDA level, and reveals in part an age-related increase in lipid peroxidation and protein oxidation, and that may occur under conditions such as vitamin E deficiency.