Swim training attenuates oxidative damage and promotes neuroprotection in cerebral cortical slices submitted to oxygen glucose deprivation

Abstract

Although it is well known that regular exercise may promote neuroprotection, the mechanisms underlying this effect are still not fully understood. We investigated if swim training promotes neuroprotection by potentiating antioxidant pathways, thereby decreasing the effects of oxidative stress on glutamate and nitric oxide release. Male Wistar rats (n=36) were evenly randomized into a trained group (TRA) (5 days/week, 8 weeks, 30 min) and a sedentary group (SED). Forty-eight hours after the last session of exercise, animals were killed and brain was collected for in vitro ischemia. Cortical slices were divided into two groups: a group in which oxidative stress was induced by oxygen and glucose deprivation (OGD), and a group of non-deprived controls (nOGD). Interestingly, exercise by itself increased superoxide dismutase activity (nOGD, SED vs. TRA animals) with no effect on pro-oxidative markers. In fact, TRA-OGD slices showed lowered levels of lactate dehydrogenase when compared with SED-OGD controls, reinforcing the idea that exercise affords a neuroprotective effect. We also demonstrated that exercise decreased glutamate and nitrite release as well as lipid membrane damage in the OGD cortical slices. Our data suggest that under conditions of metabolic stress, swim training prevents oxidative damage caused by glutamate and nitric oxide release.