The Change Of GOLPH3Expression And Akt/mTOR Signaling Pathway After Cerebral Ischemic-reperfusion And Salvianolate Intervention In Rats

Objective:To determine the molecular mechanism of neuroprotective function of Salvianolate on rat ischemia and reperfusion brain tissues, especially focus on the change of GOLPH3, Akt/p-Akt and mTOR/p-mTOR expression.Methods:A total of60healthy male SD rats were divided into three major groups:(ⅰ) sham-operated group;(ⅱ) ischemia/reperfusion model group;(ⅲ) ischemia/reperfusion with salvianolate intervention group. The right MCA was occluded with monofilament nylon suture for two hour, and then the animals were lumbar injected by Salvianolate (18mg/kg, QD) at Oh,24h and48h after reperfusion, the sham group and intervention group animals were treated with same amount of saline. All animal neurobehavioral tests were performed at the end of72h reperfusion per Longa’s method. The animals were killed and brain slices were obtained after72h of reperfusion and stained with triphenyltetrazolium chloride. The infarct volume was stained with TTC and the Cellular apoptosis were measured with TUNEL staining. Western blot analysis and quantitative real-time polymerase chain reaction (qRT-PCR) were used to determine levels of GOLPH3, Akt/p-Akt, and mTOR/p-mTOR expressions in ischemic cortex. Data were analyzed by software of SPSS19.0.Result:1) Salvianolate intervention significantly decreased cerebral infarction in rats after ischemia/reperfusion injury(p<0.05), and also mitigated the neurological deficit scores of rats in groups of72h I/R (p<0.05).2) The number of TUNEL positive cells in mode group was much more than sham group(p<0.05), salvianolate intervention significantly reduced the number of TUNEL positive cells in the cerebral cortex compared with the model group(p<0.05).3) After cerebral ischemia and reperfusion, the expression of GOLPH3were rise compared with sham group(p<0.05), the expression of GOLPH3further rise after salvianolate intervention(p<0.05).4) Compared with sham group, the expression of phosphorylation of Akt and mTOR protein were rise in model group and intervention group, which had the highest level of proteins expression in the intervention group (p<0.05).5) The expression of Akt showed no obvious difference among the sham, mode and intervention group (p<0.05), after cerebral ischemia and reperfusion, the expression of mTOR were rise compared with sham group(p<0.05), the expression of mTOR further rise after salvianolate intervention (p<0.05).Conclusion:1. After cerebral ischemia and reperfusion, the up-regulation of GOLPH3, P-Akt and P-mTOR provide neuroprotection effects.2. After cerebral ischemia and reperfusion, increasing the expression of GOLPH3and activating Akt/mTOR signaling pathway may be one of the mechanisms that salvianolate exerts neuroprotective effects.