Downregulation of miR-491-5p promotes neovascularization after traumatic brain injury

作者全名："Tang, Wei; Guo, Zong-Duo; Chai, Wei-Na; Du, Dong-Lin; Yang, Xiao-Min; Cao, Lang; Chen, Hong; Zhou, Chao; Cheng, Chong-Jie; Sun, Xiao-Chuan; Huang, Zhi-Jian; Zhong, Jian-Jun"

作者地址："[Tang, Wei; Guo, Zong-Duo; Chai, Wei-Na; Du, Dong-Lin; Yang, Xiao-Min; Chen, Hong; Zhou, Chao; Cheng, Chong-Jie; Sun, Xiao-Chuan; Huang, Zhi-Jian; Zhong, Jian-Jun] Chongqing Med Univ, Affiliated Hosp 1, Dept Neurosurg, Chongqing, Peoples R China; [Cao, Lang] Chongqing Med Univ, Affiliated Hosp 1, Dept Ophthalmol, Chongqing, Peoples R China"

通信作者："Huang, ZJ; Zhong, JJ (corresponding author), Chongqing Med Univ, Affiliated Hosp 1, Dept Neurosurg, Chongqing, Peoples R China."

来源：NEURAL REGENERATION RESEARCH

ESI学科分类：NEUROSCIENCE & BEHAVIOR

WOS号：WOS:000697690900025

JCR分区：Q2

影响因子：6.1

年份：2022

卷号：17

期号：3

开始页：577

结束页：+

文献类型：Article

关键词：　

摘要："MicroRNA-491-5p (miR-491-5p) plays an important role in regulating cell proliferation and migration; however, the effect of miR-491-5p on neovascularization after traumatic brain injury remains poorly understood. In this study, a controlled cortical injury model in C57BL/6 mice and an oxygen-glucose deprivation model in microvascular endothelial cells derived from mouse brain were established to simulate traumatic brain injury in vivo and in vitro, respectively. In the in vivo model, quantitative real-time-polymerase chain reaction results showed that the expression of miR-491-5p increased or decreased following the intracerebroventricular injection of an miR-491-5p agomir or antagomir, respectively, and the expression of miR-491-5p decreased slightly after traumatic brain injury. To detect the neuroprotective effects of miR-491-p, neurological severity scores, Morris water maze test, laser speckle techniques, and immunofluorescence staining were assessed, and the results revealed that miR-491-5p downregulation alleviated neurological dysfunction, promoted the recovery of regional cerebral blood flow, increased the number of lectin-stained microvessels, and increased the survival of neurons after traumatic brain injury. During the in vitro experiments, the potential mechanism of miR-491-5p on neovascularization was explored through quantitative real-time-polymerase chain reaction, which showed that miR-491-5p expression increased or decreased in brain microvascular endothelial cells after transfection with an miR-491-5p mimic or inhibitor, respectively. Dual-luciferase reporter and western blot assays verified that metallothionein-2 was a target gene for miR-491-5p. Cell counting kit 8 (CCK-8) assay, flow cytometry, and 2?,7?-dichlorofluorescein diacetate (DCFH-DA) assay results confirmed that the downregulation of miR-491-5p increased brain microvascular endothelial cell viability, reduced cell apoptosis, and alleviated oxidative stress under oxygen-glucose deprivation conditions. Cell scratch assay, Transwell assay, tube formation assay, and western blot assay results demonstrated that miR-491-5p downregulation promoted the migration, proliferation, and tube formation of brain microvascular endothelial cells through a metallothionein-2-dependent hypoxia-inducible factor-1 alpha /vascular endothelial growth factor pathway. These findings confirmed that miR-491-5p downregulation promotes neovascularization, restores cerebral blood flow, and improves the recovery of neurological function after traumatic brain injury. The mechanism may be mediated through a metallothionein-2-dependent hypoxia-inducible factor-1 alpha /vascular endothelial growth factor signaling pathway and the alleviation of oxidative stress. All procedures were approved by Ethics Committee of the First Affiliated Hospital of Chongqing Medical University, China (approval No. 2020-304) on June 22, 2020."

基金机构："National Natural Science Foundation of ChinaNational Natural Science Foundation of China (NSFC) [82071397, 82071332]; Youth Fund of the National Natural Science Foundation of ChinaNational Natural Science Foundation of China (NSFC) [81801230]; Excellent Scientific Research Talents Fund of the First Affiliated Hospital of Chongqing Medical University, China"

基金资助正文："This work was supported by the National Natural Science Foundation of China, Nos. 82071397 (to XCS), 82071332 (to ZDG); the Youth Fund of the National Natural Science Foundation of China, No. 81801230 (to JJZ); and the Excellent Scientific Research Talents Fund of the First Affiliated Hospital of Chongqing Medical University, China (to JJZ). The funding sources had no role in study conception and design, data analysis or interpretation, paper writing or deciding to submit this paper for publication."