栝楼桂枝汤对大鼠脑缺血/再灌注损伤后血管新生的影响

Effect of Gualou Guizhi Decoction (栝楼桂枝汤) on Angiogenesis after Cerebral Ischemia/Reperfusion Injury in Rats

目的:探讨栝楼桂枝汤对大鼠脑缺血/再灌注损伤后血管新生的影响及可能机制。方法:采用线栓法制备大鼠大脑中动脉阻塞(MCAO)模型。栝楼桂枝汤14.4 g/kg和尼莫地平0.012 g/kg治疗7 d后,采用改良神经功能缺损评分法(mNSS)评价大鼠神经功能缺损程度;Ashworth评级法评价大鼠肢体肌张力;原位末端转移酶标记技术(Tunel)检测缺血侧皮层神经元的凋亡情况;免疫组化法检测缺血侧皮层组织中白细胞分化抗原34(CD34)、低氧诱导因子-1α(HIF-1α)、血管内皮生长因子(VEGF)和血管内皮生长因子受体2(VEGFR2)蛋白的表达。结果:与假手术对照组相比,模型对照组mNSS评分、Ashworth评级和神经细胞凋亡率显著升高(P<0.01),缺血侧大脑皮层组织中CD34、HIF-1α、VEGF和VEGFR2蛋白表达均显著增多;与模型对照组相比,栝楼桂枝汤14.4 g/kg组mNSS评分、Ashworth评级和神经细胞凋亡率显著下降(P<0.01),缺血侧大脑皮层组织中CD34、HIF-1α、VEGF和VEGFR2蛋白表达均显著增多(P<0.01)。结论:栝楼桂枝汤可通过调控低氧诱导因子-1α信号通路,促进脑缺血/再灌注损伤后的血管新生,从而发挥抗脑缺血性细胞凋亡、改善神经功能缺损、缓解肢体痉挛状态的作用。

Objective:To explore the effect of Gualou Guizhi Decoction(栝楼桂枝汤)on angiogenesis after cerebral ischemia/reperfusion injury in rats and the underlying mechanism.Methods:Middle cerebral artery occlusion(MCAO)was induced in rats with the suture-occluded method.After the 7-day treatment with 14.4 g/kg Gualou Guizhi Decoction(栝楼桂枝汤)and 0.012 g/kg nimodipine,the modified neurological severity score(mNSS)and Ashworth scale were used to evaluate the neurological deficit and muscular tone of limbs,respectively.Terminal deoxynucleotidyl transferase dUTP nick end labeling(TUNEL)was employed to detect the apoptosis of cortical neurons on the ischemic side and immunohistochemistry the expression of proteins in the cortical tissue,including the cluster of differentiation 34(CD34),hypoxia inducible factor-1α(HIF-1α),vascular endothelial growth factor(VEGF),and vascular endothelial growth factor receptor 2(VEGFR2).Results:Compared with the sham operation group,the model group demonstrated high mNSS,Ashworth grade,and neuronal apoptosis rate(P<0.01)and significantly high expression of CD34,HIF-1α,VEGF,and VEGFR2 in the cerebral cortex of the ischemic side.As compared with the model group,the 14.4 g/kg Gualou Guizhi Decoction(栝楼桂枝汤)decreased the mNSS,Ashworth grade,and neuronal apoptosis rate(P<0.01)and significantly up-regulated the expression of CD34,HIF-1α,VEGF,and VEGFR2(P<0.01).Conclusion:Gualou Guizhi Decoction(栝楼桂枝汤)can promote angiogenesis after cerebral ischemia/reperfusion injury by regulating the HIF-1αsignaling pathway,thereby inhibiting cerebral ischemic cell apoptosis,alleviating neurological deficits,and relieving limb spasm.