Early Exercise after Intracerebral Hemorrhage Inhibits Inflammation and Promotes Neuroprotection in the Sensorimotor Cortex in Rats

Abstract

The present study examined the effect of early exercise on brain damage and recovery of motor function following intracerebral hemorrhage (ICH) in rats. Subjects were randomly assigned to no training after ICH (ICH), no training after sham surgery (SHAM), early treadmill exercise after ICH (ICH + ET), and late treadmill exercise after ICH (ICH + LT) groups. The ICH + ET and ICH + LT groups were trained for seven consecutive days starting on day 2 and day 9 after surgery, respectively. At post surgery day 16, the brain was surgically excised, and lesion volume, cortical thickness, neuronal number, dendritic length, and dendritic complexity were analyzed. Expression levels of IL-1b, TGF-b1, and IGF-1 mRNAs in ipsilateral sensorimotor cortex were measured by RT-PCR. The recovery of motor function in the ICH + ET group was the most accelerated. Cortical thickness and neuronal number were significantly higher in the ICH + ET group than the ICH and ICH + LT groups. The length and complexity of dendrites were also significantly greater in the ICH + ET group compared with the ICH and ICH + LT groups. Expression of IL-1b mRNA was significantly lower in the ICH + ET group than that in the ICH group. Collectively, these results suggest that early treadmill exercise after ICH promotes recovery of sensorimotor function by preventing neuronal death and ensuing cortical atrophy and by preserving dendritic structure compared with late treadmill exercise and no exercise. Early exercise may prevent neurodegeneration and functional loss by inhibiting neuroinflammation.