侧脑室注射microRNA...脑缺血再灌注损伤大鼠的机制_黎玉环.pdf

515 CHINESE JOURNAL OF ANATOMY Vol.45 No.6 2022 解剖学杂志 2022 年第 45 卷第 6 期doi：10.3969/j.issn.1001-1633.2022.06.005论 著侧脑室注射microRNA-200c经PI3K/Akt/mTOR通路 保护脑缺血再灌注损伤大鼠的机制*黎玉环 熊光润 郑永强 李 敏（宜昌市第二人民医院神经内科，宜昌 443000）摘要 目的：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：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-1（IL-1）和肿瘤坏死因子-（TNF-）及PI3K/Akt/mTOR通路表达的差异。结果：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-1、TNF-含量显著增多，miR-200c组IL-6、IL-1、TNF-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：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，发挥显著的脑保护作用。关键词 miR-200c；PI3K/Akt/mTOR通路；脑缺血；脑缺血再灌注损伤；大鼠Protection of miR-200c injected via intracerebroventricule on rats with cerebral ischemia-reperfusion injury by PI3K/Akt/mTOR pathway and its mechanism*Li Yuhuan，Xiong Guangrun，Zheng Yongqiang，Li Min（Department of Neurology，The Second Peoples Hospital of Yichang，Yichang 443000，China）Abstract 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（GSH-PX），inflammatory factors interleukin-6（IL-6），interleukin-1（IL-1）and tumor necrosis factor-（TNF-）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*湖北省卫生健康委员会 2019 2020 年度面上项目和血防专项（WJ2019M065）第 1 作者 E-mail：MAOZOU 通信作者，E-mail：收稿日期：2021-09-27；修回日期：2022-03-28 516 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 up-regulated 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 GSH-PX were significantly reduced while the MDA level was significantly increased in the model，miR-NC and miR-200c groups compared to the sham operation group，and the levels of SOD and GSH-PX in the miR-200c group were increased significantly while the MDA level was decreased significantly compared to the model group and the miR-NC group.Compared with the sham operation group，the levels of IL-6，IL-1 and TNF-in the model，miR-NC and miR-200c groups were significantly increased，and the above levels were significantly lower in the miR-200c group than those in the model group and the miR-NC group.The PI3K/Akt/mTOR pathway in the model，miR-NC and miR-200c groups was significantly inhibited compared to the sham operation group，and the activation level of PI3K/Akt/mTOR in the miR-200c group was significantly higher than that of the model group and the miR-NC group.Conclusion：Overexpression of miR-200c can inhibit the oxidative stress response and inflammatory response，reduce the neuronal apoptosis and improve the cerebral injury in model rats with cerebral ischemia-reperfusion by activating the PI3K/Akt/mTOR pathway，and it plays a significant role in cerebral protection.Key words microRNA-200c；PI3K/Akt/mTOR pathway；cerebral ischemia；cerebral ischemia-reperfusion injury；rat脑卒中是由于血管堵塞或破裂导致大脑供血不足引起脑损伤的一种急性脑血管疾病1，包括缺血性和出血