Effect of Chinese herb drug Tongxinluo on the expression of nestin and insulin-like growth factor 1 mRNA after rat cerebral ischemia-reperfusion injury

Objective To investigate the expression of nestin protein and insulin-like growth factor 1(IGF-1) mRNA in rat brain injured by ischemia-reperfusion(I/R),and observe the effects of Tongxinluo,one of Chinese herb drugs,on the expression.Methods The rat model of cerebral I/R injury,reproduced by middle cerebral artery occlusion(MCAO) and release,were divided into three groups: high-dose Tongxinluo group(given 1g/kg·d of Tongxinluo],low-dose Tongxinluo group(given 0.5g/kg·d of Tongxinluo) and control group(administration of saline).2ml of Tongxinluo or saline each time was administered to each rat and 2 times every day up to day 3,5,7,14,21 and 30 after the injury.The expression of nestin in the subventricular zone(SVZ) and hippocampal dentate gyrus zone(DG) was detected by immunohistochemistry,and the IGF-1 mRNA expression around ischemic area was detected by RT-PCR.Results Compared with the control group,the immunofluorescence magnitude of nestin-positive neurons in SVZ and DG was significantly higher in high-and low-dose Tongxinluo groups(P0.01) at each time point,especially on day 14.The immunofluorescence magnitude of nestin-positive neurons was remarkably higher in high-dose Tongxinluo group than in low-dose Tongxinluo group(P0.01) at all time points except at day 21 and day 30.The expression of IGF-1 mRNA around ischemic area significantly increased at all time points except day 3 in both high-and low-dose Tongxinluo groups(P0.01) compared with that in control group.However,no significant difference existed between the high-and low-dose Tongxinluo groups at each time point(P0.05).Conclusions Tongxinluo,a kind of Chinese herb drugs,may promote the proliferation of neural stem cells in SVZ and DG after cerebral I/R injury in rats,and the mechanism may be related to upregulation of IGF-1 mRNA induced by Tongxinluo.