No abstract

Background: Cerebral ischemic/reperfusion (I/R) causes severe damage. The purpose of this study was to evaluate the effect of exercise before or/and after I/R on inflammation and apoptosis in the CA1 region of hippocampus in rats. Methods: Male Wistar rats were assigned to six groups (sham, exercise, ischemia, exercise+ischemia, ischemia+exercise, exercise+ischemia+exercise). Rats in the exercise groups received progressive treadmill training for 8 weeks, 5 days a week prior or/and after ischemic stroke. Ischemia was induced by occlusion of both common carotid arteries for 45 min. Cell apoptosis were detected by TUNEL staining. Caspase-3, NF-kB and TNF-α were determined by immunohistochemistry, and motor function was evaluated by ladder test.Results: The cerebral ischemia caused neuronal loss through apoptosis in the hippocampus and reduced sensorimotor functions in lesion animals. The results of TUNEL and immunohistochemistry methods showed that rats in exercise+ischemia+exercise group had more significant decrease in the number of apoptotic cells and inhibited the expression of caspase-3, NF-κB and TNF-α compared to other groups (p < .05). Also, the results of Ladder test at the end of the eighth week showed significant improvements compared to 2 and 24 hours (p < .05). Conclusion: This study showed that performing treadmill exercise, whether as a preconditioning or following cerebral ischemic event, could promote neuronal and motor recovery. However, such a protocol imposes more significant effect if conducted both pre and early after ischemia compared to each one alone.