红景天苷调控GSK-3β对脑缺血/再灌注大鼠的神经保护作用

Neuroprotective effects of salidroside on GSK-3βin rats with cerebral ischemia/reperfusion

目的研究红景天苷(salidroside,Sal)对脑缺血/再灌注大鼠脑组织中caspase-9,GSK-3β,NMDAR1,GluR2蛋白表达影响。方法第一批大鼠,线栓法制备大脑中动脉闭塞模型(middle cerebral artery occlusion,MCAO)后随机分为假手术组(Sham)、模型组(MCAO)和红景天苷给药组(MCAO+Sal)各12只。红景天苷浓度为50 mg·kg^-1·d-1,给药1 d后取材。Western blot检测缺血侧脑组织中caspase-9、GSK-3β、NMDAR1、GluR2蛋白表达。第二批大鼠随机分为6组,即人工脑脊液+Sham组、GSK-3β抑制剂+Sham组、人工脑脊液+MCAO组、GSK-3β抑制剂+MCAO组,人工脑脊液+MCAO+Sal组和GSK-3β抑制剂+MCAO+Sal组,每组10只。Western blot检测以上蛋白。结果与MCAO组相比,经红景天苷干预,能够降低caspase-9的蛋白表达,促进GSK-3β蛋白磷酸化,上调NMDAR1,GluR2蛋白表达。对MCAO大鼠侧脑室注射GSK-3β抑制剂,红景天苷干预后对caspase-9、pGSK-3β、NMDAR1、GluR2蛋白表达均无作用。结论红景天苷对MCAO大鼠具有神经保护作用,主要是通过促进GSK-3β磷酸化,进而抑制caspase-9,促进NMDAR1,GluR2的蛋白表达。

Aim To study the effects of salidroside on the caspase-9,GSK-3β,NMDAR1,GluR2 in MCAO ratsand to further explore the mechanism of neuroprotection of salidroside.Methods For the first part,36 healthy male Sprague-Dawley rats were randomly divided into sham operation(Sham)group,model(MCAO)group,and salidroside(MCAO+Sal)group.Rats were administered salidroside,or vehicle,daily for 1 day,after middle cerebral artery occlusion(MCAO)2 h and reperfusion 1 h.The protein expression of GSK-3β,NMDAR1,GluR2 and caspase-9 was detected by Western blot.For the second part,rats were randomly divided into Sham group,SB216763+Shamgroup,MCAO group,SB216763+MCAO group,MCAO+Sal group,and SB216763+MCAO+Sal group.After 30 minutes of injection of GSK-3βinhibitor SB216763 or artificial cerebrospinal fluid into the lateral ventricle,the other groups were subjected to MCAO modeling except for the sham operation group.After the modeling,the administration group was given salidroside,and the material was taken after 1 day.The protein expression of GSK-3β,NMDAR1,GluR2 andcaspase-9 was detected by Western blot.Results Compared with MCAO group,salidroside could reduce the protein expression of cleaved caspase-9 protein in mitochondria and promote the expression of pGSK-3β,NMDAR1,GluR2 protein after 1 day salidroside treatment.And the treatment of salidroside and GSK-3βinhibitor did not show remarkable additive effects.Conclusions Salidroside has a neuroprotective effect on MCAO rats,mainly by promoting GSK-3βphosphorylation,thereby inhibiting caspase-9 and promoting protein expression of NMDAR1 and GluR2.