Li Jie, Lv Hui, Che Yuqin
Department of Neurology, The Fourth Affiliated Hospital of China Medical University, No. 4, Chongshan East Road, Huanggu District, Shenyang, 110032, Liaoning, People's Republic of China.
Cell Mol Neurobiol. 2020 Nov;40(8):1307-1319. doi: 10.1007/s10571-020-00815-4. Epub 2020 Apr 15.
Ischemic stroke is a serious disease with limited prevention methods, and various genes and microRNAs (miRNAs) have been found to be dysregulated in the pathogenesis of this disease. This study aims to explore the potential role of miR-381-3p in ischemic stroke, along with its underlying mechanism. A mouse model of ischemic stroke was developed using middle cerebral artery occlusion. Next, the expression of mitogen-activated protein kinase kinase kinase 8 (Map3k8) and CCAAT enhancer binding protein beta (Cebpb) was determined by RT-qPCR. Gain- and loss-of-function approaches were applied to analyze the effects of miR-381-3p, Cebpb and Map3k8 on the biological functions of endothelial progenitor cells (EPCs) with the involvement of the tumor necrosis factor-α (TNF-α) signaling pathway. In addition, dual luciferase reporter gene assay was performed for the analysis of the relationship among miR-381-3p, Map3k8 and Cebpb. Further, rescue experiment was performed with the help of JNK/p38 specific agonist, Anisomycin. Map3k8 and Cebpb were highly expressed in ischemic stroke. Loss-of-function of Map3k8 or Cebpb in EPCs contributed to accelerated proliferation, migration and angiogenesis of EPCs. Next, miR-381-3p downregulated the expression of its two target genes, Map3k8 and Cebpb. miR-381-3p overexpression promoted angiogenesis of EPCs, and inhibited inflammation, which could be reversed by restoration of Map3k8 or Cebpb. Additionally, silencing Map3k8 or Cebpb inhibited the activation of TNF-α signaling pathway. Furthermore, Anisomycin treatment could enhance inflammation and inhibit angiogenesis. Taken together, miR-381-3p downregulates Map3k8 and Cebpb to protect against ischemic stroke, broadening our understanding of the pathogenesis of ischemic stroke.
缺血性中风是一种预防方法有限的严重疾病，人们发现多种基因和微小RNA（miRNA）在该疾病的发病机制中表达失调。本研究旨在探讨miR-381-3p在缺血性中风中的潜在作用及其潜在机制。采用大脑中动脉闭塞法建立缺血性中风小鼠模型。接下来，通过RT-qPCR测定丝裂原活化蛋白激酶激酶激酶8（Map3k8）和CCAAT增强子结合蛋白β（Cebpb）的表达。应用功能获得和功能丧失方法，分析miR-381-3p、Cebpb和Map3k8在肿瘤坏死因子-α（TNF-α）信号通路参与下对内皮祖细胞（EPCs）生物学功能的影响。此外，进行双荧光素酶报告基因测定以分析miR-381-3p、Map3k8和Cebpb之间的关系。此外，借助JNK/p38特异性激动剂茴香霉素进行挽救实验。Map3k8和Cebpb在缺血性中风中高表达。EPCs中Map3k8或Cebpb功能丧失有助于EPCs的增殖、迁移和血管生成加速。接下来，miR-381-3p下调其两个靶基因Map3k8和Cebpb的表达。miR-381-3p过表达促进EPCs的血管生成并抑制炎症，这可通过恢复Map3k8或Cebpb来逆转。此外，沉默Map3k8或Cebpb可抑制TNF-α信号通路的激活。此外，茴香霉素处理可增强炎症并抑制血管生成。综上所述，miR-381-3p下调Map3k8和Cebpb以预防缺血性中风，拓宽了我们对缺血性中风发病机制的理解。
