摘要
目的探讨丙酮酸乙酯(EP)对缺氧缺血性脑损伤(HIBI)新生大鼠海马神经元凋亡及磷脂酰肌醇3-激酶(PI3-K)/蛋白激酶(Akt)信号通路的影响。方法将7 d龄Wistar大鼠随机分为假手术组(sham组)、模型组(HIBI组)、丙酮酸乙酯处理组(EP组,于缺血缺氧前30 min行3 mg/kg EP腹膜内注射)。采用Rice法制备HIBI模型,透射电子显微镜下观察新生大鼠海马区神经元变化;2,3,5-三苯基四氮唑-水合物(TTC)染色法检测缺氧缺血脑组织损伤情况;TUNEL法和双重免疫荧光染色法检测海马神经元凋亡情况;免疫组织化学法和蛋白免疫印迹法检测海马组织p-Akt和Bcl-2蛋白表达情况。结果模型制备24 h后,sham组神经元结构基本正常,HIBI组神经元呈气蚀性改变,EP组神经元气蚀性变化减少,神经元受损情况改善。模型制备48 h后,与sham组比较,HIBI组梗死面积显著增加(P<0.05);与HIBI组比较,EP组梗死面积显著降低(P<0.05)。sham组TUNEL阳性染色细胞少,而HIBI组TUNEL阳性细胞显著高于sham组(P<0.05);EP组TUNEL阳性细胞数显著降低(P<0.05)。HIBI组双标记阳性细胞比例显著高于sham组(P<0.05);与HIBI组比较,EP组双标记阳性细胞比例显著降低(P<0.05)。与HIBI组比较,EP组p-Akt和Bcl-2的平均光密度值显著高于HIBI组(P<0.05);EP组p-Akt和Bcl-2蛋白表达水平显著增加(P<0.05)。结论 EP处理通过激活PI3K/Akt信号通路,促进Bcl-2表达,缓解HIBI引起的神经元凋亡,从而发挥脑保护作用。
Objective To investigate the effect of ethyl pyruvate(EP)on apoptosis and phosphatidylinositol 3-kinase(PI3-K)/protein kinase(Akt)signaling pathway in hippocampal neurons of neonatal rats with hypoxic-ischemic brain damage(HIBI).Methods 7-day-old Wistar rats were randomly divided into three groups:sham group,model group(HIBI group),ethyl pyruvate treatment group(EP group,3 mg/kg EP were intraperitoneal injected before 30 min of ischemia and hypoxia).The HIBI model was prepared by Rice method,and the changes of neurons in hippocampus were observed under transmission electron microscope.Brain injury in hypoxia-ischemia was deteted by TTC Staining.TUNEL and double immun fluorescence staining were used for detection of neuronal apoptosis in hippocampus.The expression of p-Akt and Bcl-2 protein in hippocampus were detected by immunohistochemistry and western blot.Results After 24 hours of model preparation,the neurons in the sham group were normal,but in the HIBI group were changed to cavitation,the erosional changes of the neurons were reduced in the EP group and the neuronal damage was improved.After 48 h of model preparation,the infarct size of HIBI group was significantly increased(P<0.05)compared with that in sham group.The infarct size of EP group was significantly decreased(P<0.05).The number of TUNEL positive cells in HIBI group was significantly higher than that in sham group(P<0.05).Compared with HIBI group,the number of TUNEL positive cells in EP group was significantly decreased(P<0.05).The proportion of double labeled positive cells in HIBI group was significantly higher than that in sham group(P<0.05).Compared with HIBI group,the number of double-labeled positive cells in EP group was significantly lower(P<0.05).Compared with HIBI group,the MOD values of p-Akt and Bcl-2 in EP group were significantly higher than those in HIBI group(P<0.05),the expression of p-Akt and Bcl-2 protein in EP group were significantly increased(P<0.05).Conclusion EP treatment can promote the expression of Bcl-2 and alleviate neuronal apoptosis induced by HIBI according to activating PI3K/Akt signaling pathway,thus exerting the protective effect of brain.
作者
周一博
苏军
ZHOU Yibo;SU Jun(Zhengzhou Children′s Hospital,Zhengzhou 450000,Henan,China)
出处
《中西医结合心脑血管病杂志》
2019年第4期519-524,共6页
Chinese Journal of Integrative Medicine on Cardio-Cerebrovascular Disease
基金
河南省医学科技攻关计划项目(No.201503208)
关键词
缺血缺氧性脑损伤
大鼠
丙酮酸乙酯
海马神经元
细胞凋亡
PI3-K/Akt信号通路
hypoxic-ischemic brain injury
rat
ethyl pyruvate
hippocampal neurons
apoptosis
phosphatidylino sitol 3-kinase/protein kinase signaling pathway
