Zhongguo cuzhong zazhi (Nov 2024)
肉苁蓉总苷经PI3K-Akt信号通路对大鼠脑缺血再灌注损伤的神经保护作用及机制研究 Neuroprotective Effect and Mechanism of Glycosides of Cistanche on Cerebral Ischemia-Reperfusion Injury in Rats Based on PI3K-Akt Signaling Pathway
Abstract
目的 探究肉苁蓉总苷通过激活PI3K-Akt信号通路对大鼠脑缺血再灌注损伤（cerebral ischemia-reperfusion injury，CIRI）的保护作用及机制。 方法 60只雄性Wistar大鼠随机分为假手术组、模型组、肉苁蓉总苷组、尼莫地平组。采用改良线栓法构建大鼠CIRI模型。采用Zea-Longa神经功能评分评估各组大鼠中枢神经系统缺损状况，2,3,5-氯化三苯基四氮唑染色计算各组模型大鼠脑梗死面积，原位末端转移酶标记法染色检测细胞凋亡率，免疫荧光染色分析凋亡相关因子的表达情况，蛋白免疫印迹以及荧光定量PCR检测各组大鼠凋亡相关因子及PI3K-Akt信号通路相关分子表达水平。 结果 与假手术组相比，CIRI模型大鼠神经系统缺损症状严重，神经功能评分升高（P＜0.05），运动能力减退，脑梗死面积增大，凋亡细胞增多，促凋亡因子B淋巴细胞瘤-2基因（B-cell lymphoma-2，Bcl-2）相关X蛋白（Bcl-2 associated X，Bax）和细胞色素C（cytochrome C，CytC）表达增加（P＜0.05），Bcl-2、Bcl-2/Bax、磷脂酰肌醇3激酶（phosphoinositide 3-kinase，PI3K）、磷酸化蛋白激酶B（phospho-protein kinase B，p-Akt）、p-Akt/Akt表达降低（P＜0.05）。与模型组相比，肉苁蓉总苷能够促进CIRI模型大鼠运动功能的恢复，减小脑梗死面积，调控神经细胞凋亡，抑制Bax、CytC的表达（P＜0.05），促进Bcl-2、Bcl-2/Bax、PI3K、p-Akt、p-Akt/Akt的表达。 结论 肉苁蓉总苷可能通过激活PI3K-Akt信号通路，抑制神经细胞凋亡，对CIRI模型大鼠发挥神经保护作用。 Abstract: Objective To investigate the protective effects and mechanisms of glycosides of cistanche (GCs) on cerebral ischemia-reperfusion injury (CIRI) in rats by activating PI3K-Akt signaling pathway. Methods Sixty male Wistar rats were randomly divided into the sham group, the model group, the GCs group and the nimodipine group. The modified embolism method was used to construct a rat model of CIRI. The deficits in the central nervous system of rats in each group were assessed by the Zea-Longa neurological function score. The area of cerebral infarction of rats in each group was calculated by 2, 3, 5-triphenyltetrazolium chloride staining. The apoptosis rate was detected by terminal-deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling staining. The expression of apoptosis-related factors was analyzed by immunofluorescence staining. Western blot and fluorogenic quantitative PCR were used to detect the expression levels of apoptosis-related factors and molecules related to the PI3K-Akt signaling pathway in each group of rats. Results Compared with the sham group, the CIRI model rats exhibited severe neurological deficit symptoms, increased neurological function scores (P<0.05), reduced motor function, enlarged cerebral infarction area, increased apoptotic cells, and elevated expression of pro-apoptotic factors B-cell lymphoma-2 (Bcl-2) associated X protein (Bax) and cytochrome C (CytC) (P<0.05). The expression levels of Bcl-2, Bcl-2/Bax, phosphoinositide 3-kinase (PI3K), phospho-protein kinase B (p-Akt), and p-Akt/Akt were decreased (P<0.05). Compared with the model group, GCs promoted the recovery of motor function, reduced the area of cerebral infarction, regulated neuronal apoptosis, inhibited the expression of Bax and CytC (P<0.05), and promoted the expression of Bcl-2, Bcl-2/Bax, PI3K, p-Akt, and p-Akt/Akt in CIRI model rats. Conclusions GCs may exert neuroprotective effects on CIRI model rats by activating the PI3K-Akt signaling pathway and inhibiting neuronal apoptosis.
Keywords
