侧脑室注射microRNA-200c经PI3K/Akt/mTOR通路保护脑缺血再灌注损伤大鼠的机制  

Protection of miR-200c injected via intracerebroventricule on rats with cerebral ischemia-reperfusion injury by PI3K/Akt/mTOR pathway and its mechanism*

作　　者：黎玉环 熊光润 郑永强 李敏 Li Yuhuan;Xiong Guangrun;Zheng Yongqiang;Li Min(Department of Neurology,The Second People’s Hospital of Yichang,Yichang 443000,China)

机构地区：[1]宜昌市第二人民医院神经内科,宜昌443000

出　　处：《解剖学杂志》2022年第6期515-520,共6页Chinese Journal of Anatomy

基　　金：湖北省卫生健康委员会2019~2020年度面上项目和血防专项(WJ2019M065)。

摘　　要：目的:探讨侧脑室注射microRNA-200c(miR-200c)调控磷酯酰肌醇-3-激酶(PI3K)/蛋白激酶B(Akt)/哺乳动物雷帕霉素靶蛋白(mTOR)通路在大鼠脑缺血再灌注损伤过程中的保护作用及相关机制。方法:SD大鼠随机分为假手术组、模型组、miR-NC组和miR-200c组,模型组、miR-NC和miR-200c组采用线栓法构建脑缺血再灌注损伤模型;模型制作成功后,侧脑室分别注射生理盐水、miR-NC和miR-200c,假手术组不进行缺血再灌注处理及任何侧脑室注射。观察各组大鼠神经功能评分、脑含水量、脑梗死体积、神经细胞凋亡相关指标[B淋巴细胞瘤-2(Bcl2)、Bcl-2关联X蛋白(Bax)和半胱氨酸天冬氨酸蛋白酶3(caspase 3)]、氧化应激指标[超氧化物歧化酶(SOD)、丙二醛(MDA)和谷胱甘肽过氧化物酶(GSH-PX)]、炎症因子[白细胞介素-6(IL-6)、白细胞介素-1β(IL-1β)和肿瘤坏死因子-α(TNF-α)]及PI3K/Akt/mTOR通路表达的差异。结果:与假手术组相比,其他3组神经功能评分、脑含水量和脑梗死体积均显著升高,miR-200c组神经功能评分、脑含水量和脑梗死体积显著低于模型组和miR-NC组。与假手术组相比,其他3组Bax、caspase 3蛋白表达显著上调,Bcl2蛋白表达显著下调,miR-200c组Bax、caspase 3蛋白表达显著低于模型组和miR-NC组,Bcl2蛋白表达显著高于模型组和miR-NC组。与假手术组相比,其他3组SOD和GSH-PX含量显著降低,MDA含量显著升高,miR-200c组SOD和GSH-PX含量较模型组和miR-NC组显著升高,MDA含量显著降低。与假手术组相比,其他3组IL-6、IL-1β、TNF-α含量显著增多,miR-200c组IL-6、IL-1β、TNF-α含量显著低于模型组和miR-NC组。与假手术组相比,其他3组PI3K/Akt/mTOR通路被显著抑制,miR-200c组PI3K/Akt/mTOR的活化水平显著高于模型组和miR-NC组。结论:过表达miR-200c通过激活PI3K/Akt/mTOR通路,抑制脑缺血再灌注模型大鼠氧化应激反应和炎症反应,减轻神经细胞凋亡,改善脑损伤,发�Objective:To investigate the protective effect and related mechanism of microRNA-200c(miR-200c)injected intracerebro-ventricularly by phosphatidylinositol-3-kinase(PI3K)/protein kinase B(Akt)/mammalian target of rapamycin(mTOR)pathway on rats with cerebral ischemia-reperfusion injury.Methods:SD rats were randomly divided into a sham operation group,a model group,a miR-NC group and a miR-200c group.The cerebral ischemia-reperfusion injury model was constructed with suture method,and saline,miR-NC and miR-200c were injected into the lateral ventricle of rats in model,miR-NC,and miR-200c group separately.The sham operation group did not undergo ischemia-reperfusion treatment and any intracerebroventricular injection.The neurological function score,brain water content,cerebral infarction volume,nerve cell apoptosis-related indicators[B-cell lymphoma-2(Bcl2),Bcl-2 associated X protein(Bax)and cysteine aspartic protease-3(caspase 3)],oxidative stress indicators[superoxide dismutase(SOD),malondialdehyde(MDA)and glutathione peroxidase(GSHPX)],inflammatory factors[interleukin-6(IL-6),interleukin-1β(IL-1β)and tumor necrosis factor-α(TNF-α)]and expression of PI3K/Akt/mTOR pathway were observed in each group.Results:Compared with the sham operation group,the neurological function score,brain water content and cerebral infarction volume of the model,miR-NC and miR-200c groups were significantly increased,and the above three indicators of the miR-200c group was significantly lower than that of the model group and the miR-NC group.The protein expression of Bax and caspase 3 in the model group,miR-NC group and miR-200c group was significantly upregulated while the Bcl2 protein expression was significantly down-regulated compared to the sham operation group.The protein expression of Bax and caspase 3 in the miR-200c group was significantly lower than that in the model group and the miR-NC group while the expression of Bcl2 protein was significantly higher than that in the model group and the miR-NC group.The levels of SOD and

关 键 词：MIR-200C PI3K/Akt/mTOR通路 脑缺血 脑缺血再灌注损伤 大鼠 

分 类 号：R743.3[医药卫生—神经病学与精神病学]