葛根素对大鼠脑缺血再灌注侧皮质区细胞凋亡及p-Akt (Ser473)表达的影响

目的 观察葛根素(Pue)对大鼠脑缺血再灌注缺血半暗带侧皮质区神经细胞凋亡及p-Akt(Ser473)表达的影响，进一步探讨Pue的神经保护机制。方法 48只实验大鼠随机分为4组：假手术组、缺血再灌注组、Pue组及Pue+LY组。应用栓线法建立大鼠脑缺血再灌注模型，Pue组及Pue+LY组分别予Pue及Pue+特异性PI3K激酶抑制剂LY294002进行干预。于缺血1h再灌注24h行神经功能缺损评分，TTC染色测量梗死面积，Tunel法检测细胞凋亡数目，免疫组化检测p-Akt(Ser473)表达,并进行图像分析。结果 Pue组较缺血再灌注组神经功能缺损评分明显降低(P<0.05)，凋亡细胞数显著下降(P<0.05)，p-Akt(Ser473)表达显著升高(P<0.05)；Pue+LY组较Pue组神经功能缺损评分明显升高(P<0.05)，凋亡细胞数显著增加(P<0.05)，p-Akt(Ser473)表达显著降低(P<0.05)。结论 激活PI3K/Akt信号通路可能是Pue减少神经细胞凋亡、起到神经保护作用的机制之一。

Effects of Puerarin on the Neurocyte Apoptosis and p-Akt(Ser473) Expressions in Rats with Cerebral Ischemia/Reperfusion Injury

Objective To observe the effects of puerarin(Pue) on the neurocyte apoptosis and the p-Akt(Ser473) expression in the ischemic penumbra of rats with cerebral ischemia/reperfusion(I/R).Methods The 48 Sprague-Dawley rats were randomly divided into four groups,i.e.,the sham-operation group,the I/R group,the Pue treatment group,and the Pue+ LY294002 treatment group(Pue+LY),12 in each group.The cerebral I/R rat model was established by Longa’s suture method.Pue and Pue+specific P13K kinase inhibitor,i.e.,LY294002 were administered.The score of the neurological deficit was estimated 1 h followed by 24 h reperfusion.The infarct volume was measured using TTC staining.The number of apoptotic neurons were detected using Tunel method.The expressions of p-Akt(Ser473) was detected using immunohistochemical assay,and the images were analyzed.Results The score of the neurological deficit decreased more obviously,the number of apoptosis decreased more significantly,the expressions of p-Akt(Ser473) increased more significantly in the Pue group than in the I/R group(all P<0.05).The score of the neurological deficit increased more obviously,the number of apoptosis increased more significantly,the expression of p-Akt(Ser473) decreased more significantly in the Pue+LY group than in the Pue group(all P<0.05).Conclusion Pue reduced the apoptosis of neurocytes and had protective effects against cerebral I/R injury possibly through activating the PI3K/Akt signaling pathway.