Effect of exercise-training on lipid peroxidation and antioxidant enzymes in the aorta of fructose-fed rats

Previous studies have shown that exercise training attenuates the increase in blood pressure, and reverses the changes in plasma lipid profile, in rats fed fructose. We have now studied the effect of exercise training on the susceptibility of the aorta to lipid peroxidation and on the activities of antioxidant enzymes in rats given fructose (10%) in drinking water for 6 weeks. Fructose-fed rats were more susceptible to lipid peroxidation as measured by thiobarbituric acid-reactivity, and antioxidant enzyme activities were significantly lower. Exercise training for 6 weeks caused a reduction in the production of thiobarbituric acid-reactive substances and rises in antioxidant enzyme activities. Fructose-fed rats had elevated blood pressure, hyperglycaemia and hyperinsulinaemia. These changes were reversed in fructose-fed rats given exercise training. The plasma glucose level following an oral glucose load was higher in fructose-fed rats than in controls. Exercise training also prevented this exaggerated response. These findings show that increased aorta lipid peroxidation plays a role in the pathology associated with fructose-feeding, and that exercise training reduces the lipid peroxidation by inducing antioxidant enzymes. Med Sci Res 26:439-443 (C) 1998 Lippincott-Raven Publishers.