Neuroprotective Effects of Exercise on Brain Edema and Neurological Movement Disorders Following the Cerebral Ischemia and Reperfusion in Rats

Abstract

Introduction:Cerebral ischemia and reperfusion causes physiological and biochemical changes in the neuronal cells that will eventually lead to cell damage. Evidence indicates that exercise reduces the ischemia and reperfusion-induced brain damages in animal models of stroke. In the present study, the effect of exercise preconditioning on brain edema and neurological movement disorders following the cerebral ischemia and reperfusion in rats was investigated.Methods:Twenty-one adult male wistar rats (weighing 260–300 g) were randomly divided into three groups: sham operated, exercise plus ischemia, and ischemia group (7 rats per group). The rats in exercise group were trained to run on a treadmill 5 days a week for 4 weeks. Transient focal cerebral ischemia and reperfusion were induced by middle cerebral artery occlusion (MCAO) for 60 minutes, followed by reperfusion for 23 hours. After 24 hours ischemia, movement disorders were tested by a special neurological examination. Also, cerebral edema was assessed by determining the brain water content.Results:The results showed that pre-ischemic exercise significantly reduced brain edema (P<0.05). In addition, exercise preconditioning decreased the neurological movement disorders caused by brain ischemia and reperfusion (P<0.05).Conclusion:Preconditioning by exercise had neuroprotective effects against brain ischemia and reperfusion-induced edema and movement disorders. Thus, it could be considered as a useful strategy for prevention of ischemic injuries, especially in people at risk.

Quercetin attenuates neuronal cells damage in a middle cerebral artery occlusion animal model

“…Neurological function tests were performed 24 hr after the MCAO procedure. Neurological function was evaluated according to a five-point scoring system: no deficit (0), normal posture but failure to extend the forepaw on the contralateral side of the ischemic region (1), normal posture but circling to the contralateral side of the ischemic region (2), falling to the contralateral side of the ischemic region (3), or no spontaneous movement (4) [ 17 , 23 , 32 ]. To measure edema in the cerebral cortex, the right cerebral cortex was immediately isolated from brain tissue and its weight was measured as the wet weight.…”

“…After the wet weight measurement, the right cerebral cortex was dried at 100°C for 24 hr, and the weight of the dried tissue was measured as the dry weight. To determine the index of cerebral cortex edema, the brain water content (%) was calculated as follows: [(wet weight−dry weight)/wet weight] × 100 [ 17 , 32 ].…”

Positive Effects of Post-ischemic Forced Treadmill Training on Sensorimotor and Learning Outcomes Following Transient Global Cerebral Ischemia

“…Performing endurance exercise (run and/or reach training) five days after the induction of stroke increased recovery of skilled reaching ability but did not modulate gross motor skills, such as postural support (forelimb asymmetry test) and gait (ladder rung walking test) (39). In another study, pre-ischemic running on treadmill for four weeks, five days a week significantly reduced brain edema and neurological movement disorders caused by brain ischemia and reperfusion in male rats (40). Pre-stroke exercise in form of treadmill running (30 min a day for three weeks) decreased neurologic deficits and infarct volume in the frontoparietal cortex and dorsolateral striatum (41).…”

Endogenous neuroprotective potential due to preconditioning exercise in stroke

“…Exercise precondi-tioning improves different structural and functional components of the BBB. For example, pre-ischemic exercise improves BBB function and reduces cerebral edema 42,43) . Additionally, pre-ischemic exercise enhances the integrity of the basal lamina after ischemic stroke by inhibiting the overexpression of matrix metalloproteinase-9 (MMP-9) 42 ) .…”