微小RNA132参与阿尔茨海默病模型鼠神经元凋亡的机制研究  

Molecular mechanism of microRNA-132 regulation of neuronal apoptosis in mice with Alzheimer′s disease

作　　者：赵昆朋 马敬[1] 李玉玲[1] 肖伟霞[1] 李玉凤[1] Zhao Kunpeng;Ma Jing;Li Yuling;Xiao Weixia;Li Yufeng(Department of Geriatric Psychiatry,the Second Affiliated Hospital of Xinxiang Medical University,Henan Mental Hospital,Xinxiang 453002,China)

机构地区：[1]新乡医学院第二附属医院河南省精神卫生中心老年精神科,453002

出　　处：《中华精神科杂志》2021年第6期455-460,共6页Chinese Journal of Psychiatry

基　　金：国家自然科学基金(U1504809,31571106);河南省医学科技攻关计划(LHGJ20190478);河南省科技攻关项目(212102310588)。

摘　　要：目的探讨微小RNA132(microRNA132,miRNA-132)调控阿尔茨海默病(Alzheimer′s disease,AD)模型鼠(AD模型鼠)神经元凋亡的分子机制。方法本研究起止时间为2016年1月至2021年3月,动物分组为AD转基因模型鼠组(AD模型鼠组)和同窝阴性对照鼠组(同窝阴性鼠组),后续实验中的每组动物数量均为3只;采用定量多聚酶链反应(quantitative polymerase chain reaction,qPCR)方法检测2组小鼠皮质和海马组织中的miRNA-132表达水平,采用脱氧核糖核苷酸末端转移酶介导的缺口末端标记法(terminal-deoxynucleotidyl transferase mediated nick end labeling,TUNNEL)检测2组小鼠脑组织皮质神经细胞凋亡情况,采用免疫印迹法检测2组小鼠全脑组织中的凋亡相关蛋白的表达水平,采用双荧光酶报告系统确认miRNA-132直接调控的下游靶点蛋白。2组实验数据比较采用独立样本t检验,以P<0.05为差异有统计学意义。结果与同窝阴性鼠组相比,AD模型鼠组皮质和海马的miRNA-132表达水平均明显下调(P<0.01),脑皮质神经元凋亡显著增加(P<0.01),全脑组织凋亡相关蛋白BAX、Caspase-3、FOXO3a均明显上升(P<0.05或P<0.01);双荧光酶报告系统显示miRNA-132可以和下游蛋白FOXO3a直接相互作用,AD模型组的荧光素酶活性明显降低(P<0.01)。结论miRNA-132表达下降诱导了AD鼠神经元凋亡,机制可能是通过上调FOXO3a的表达,激活凋亡相关蛋白BAX和Caspase-3实现的。Objective To investigate the molecular mechanism of miR-132 regulation of neuronal apoptosis in Alzheimer′s disease model mice(AD mice).Methods The study started and ended from 2016.01 to 2021.03.The animals were divided into the AD transgenic model mice group(AD model mice group)and the littermate negative control mice group(litter negative mice group).The number of animals in each group in the subsequent experiment was three mouses.The levels of miR-132 in the cortex and hippocampus of the two groups were detected by quantitative PCR.The TUNNEL(terminal-deoxynucleotidyl transferase-mediated nick end labeling)method was used to detect neuronal apoptosis in the brain tissue of the two groups of mice.The expression levels of apoptosis-related proteins in brain tissue of two groups of mice were detected by immunoblotting.The dual-luciferase reporter system recognizes downstream target proteins that miRNA-132 directly regulated.The independent sample Student′s t-test was used to compare the two groups,and the difference was statistically significant with P<0.05.Results Compared with the littermate-negative mice,the relative expression of miRNA-132 in the cortex and hippocampus of AD mice was significantly down-regulated(P<0.01).The results of TUNNEL showed a significant increase in neuronal apoptosis in the brain of AD mice relative number of apoptotic cells(P<0.01).Western blot results showed that the relative expression of apoptosis-related proteins in the brain of AD mice was significantly increased(P<0.05 or P<0.01).The dual-luciferase reporter system showed that miRNA-132 could directly interact with the downstream protein FOXO3a,and the luciferase activity of the AD model group was significantly reduced(P<0.01).Conclusions miRNA-132 reduction may disinhibit apoptosis-related proteins BAX and Caspase-3 by up-regulating FOXO3a expression to speed up neuronal apoptosis in AD mice.

关 键 词：阿尔茨海默病 细胞凋亡 小鼠 

分 类 号：R749.16[医药卫生—神经病学与精神病学]