We have evaluated the effect of exercise, Vitamin E and a combination of both on the antioxidant enzymes (AOEs)-superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and catalase (CAT) along with the products of lipid peroxidation (LP)-malondialdehyde (MDA) and lipofuscin-like auto fluorescent substances (LF-like AFS) in discrete brain regions of rats of 4 (young adults), 8 (old adults), 12 (middle-age) and 22 months (mos) old of age. Hippocampus (HC) showed greater increase in GSH-Px activity than cerebral cortex (CC) to exercise and Vitamin E and was irrespective of the age. A combination of both was effective in the CC of all age groups but not in the supplemented sedentary of 12-and 22-mo-olds. CAT activity increased significantly in the HC of supplemented and trained rats but not in the combination group of any age. SOD increased in both the regions of supplemented trainees. However, old were more benefited in terms of maximal elevation in the HC. Vitamin E reduced MDA content in both regions of adult. LF-like AFS decreased significantly in supplemented sedentary and trainees of all ages. Our results demonstrate that an age-related deficit in AOEs in the CC and HC can be overcome through Vitamin E plus exercise, and further suggests the rationale for looking at these markers of oxidative stress in several age-related neuronal diseases.

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We examined a suitable swim program of different intensities and durations that could evoke changes in the myocardial antioxidant capacity in 22-month-old rats. Male rats (Rattus norvegicus) were assigned to either a sedentary control (SE-C) group or one of six trainee groups. Animals were swim-exercised for 4 weeks with either 20 min or 40 miny day, and three intensities, low, moderate and high. Low-intensity at 20 minyday elicited maximum swim velocity (S ) v and endurance capacity (P-0.05). While serum total cholesterol, triglyceride and low-density lipoprotein (LDL-C) levels were significantly reduced, high-density lipoprotein (HDL-C) showed an increase (P-0.05) in low-intensity trained rats (20 minyday) over SE-C. Notable reduction in blood lactate was also evident. Exercise training significantly increased superoxide dismutase (Mn-SOD), decreased lipid peroxidation products, malondialdehyde and lipofuscin in the left and right ventricles. Increased Mn-SOD with concomitant decrease in lipofuscin in left ventricle was significantly greater than in right ventricle. Moderate-to high-intensity exercise was not effective in either reducing lipid peroxidation products or elevating Mn-SOD activity. These data suggest that swim training at low-intensity of 20 minyday is beneficial as a major protective adaptation against oxidative stress in old myocardium. ᮊ

The aim of our study was to compare and assess the effectiveness of antioxidant mixtures on the erythrocytes (RBC) of adult male albino rats (Wister) subjected to simulated intermittent high altitudes--5,100 m (AL(1)) and 6,700 m (AL(2))--to induce oxidative stress (OS). To achieve our objective, we pre-supplemented four sets of animals with different antioxidant mixtures [vitamin E (vit.E; 50 IU/kg BW), vitamin C (vit.C; 400 mg/kg) and L: -carnitine (400 mg/kg)] in different combinations [M1 (vit.E+vit.C), M2 (vit.C+carnitine), M3 (vit.E+carnitine) and M4 (vit.C+vit.E+carnitine)] for 30 days prior to as well during exposure to intermittent hypobaric hypoxia (IHH). Membrane instability, in terms of osmotic fragility and hemolysis, decreased in RBCs of supplemented animals. There was a significant increase in the activity of glutathione peroxidase in the RBCs of supplemented animals. We confirmed OS imposed by IHH with assays relating to lipid [thiobarbituric acid reactive substances (TBARS) and lipofuscin (LF)] and protein (carbonyl, PrC) oxidation, and found a positive correlation between PrC and hemolysis, with a decrease in both upon supplementation with M3 and M4 mixtures. Fluorescence microscopic observation showed a maximum decrease in the LF content in rats administered M4 and M1 compared to those on M2 and M3 mixtures at both altitudes. We suggest that multiple antioxidant fortifications are effective in overcoming increased OS experienced by RBCs at high altitudes.