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 incr ease in blood pressure, and reverses the changes in plasma lipid profi le, in rats fed fructose. We have now studied the effect of exercise t raining on the susceptibility of the aorta to lipid peroxidation and o n the activities of antioxidant enzymes in rats given fructose (10%) i n drinking water for 6 weeks. Fructose-fed rats were more susceptible to lipid peroxidation as measured by thiobarbituric acid-reactivity, a nd antioxidant enzyme activities were significantly lower. Exercise tr aining for 6 weeks caused a reduction in the production of thiobarbitu ric acid-reactive substances and rises in antioxidant enzyme activitie s. Fructose-fed rats had elevated blood pressure, hyperglycaemia and h yperinsulinaemia. These changes were reversed in fructose-fed rats giv en exercise training. The plasma glucose level following an oral gluco se load was higher in fructose-fed rats than in controls. Exercise tra ining also prevented this exaggerated response. These findings show th at increased aorta lipid peroxidation plays a role in the pathology as sociated with fructose-feeding, and that exercise training reduces the lipid peroxidation by inducing antioxidant enzymes. Med Sci Res 26:43 9-443 (C) 1998 Lippincott-Raven Publishers.