ABSTRACT

Studies have extensively focused on the involvement of microRNAs (miRNAs) in cerebral ischemia/reperfusion (I/R) injury but not much on the specific role of miR-20a. Hence, this study is purposed to decipher whether miR-20a could regulate cadherin 1 (CDH1) to affect cerebral I/R injury in rats. Rat transient middle cerebral artery occlusion model (MCAO) was established. Rats were injected with lentiviral solution containing miR-20a inhibitor, or overexpressed CDH1 or combined depleted miR-20a and CDH1 to explore their roles in cerebral I/R injury. Oxidative stress-related factors, miR-20a, CDH1, nuclear factor-kappaB (NF-κB) and Nestin expression in brain tissues were detected by RT-qPCR and western blot assay. The target relation between miR-20a and CDH1 was predicted by online website and further confirmed by luciferase activity assay. In rats with cerebral I/R injury, increased miR-20a and decreased CDH1 were found in brain tissues. Reduction of miR-20a or elevation of CDH1 attenuated behavior function in MCAO rats. Inhibiting miR-20a or restoring CDH1 restrained oxidative stress, attenuated pathological damage of neurons, promoted neuron survival, and down-regulated NF-κB and Nestin expression in brain tissues of MCAO rats. CDH1 was determined to a target gene of miR-20a. This study elucidates that down-regulating miR-20a elevates CDH1 to protect neurons from cerebral I/R injury, which paves a new way for treatment of cerebral I/R injury.

 抽象的

研究广泛关注 microRNA (miRNA) 在脑缺血/再灌注 (I/R) 损伤中的作用，但对 miR-20a 的具体作用关注较少。因此，本研究旨在解析miR-20a是否可以调节钙粘蛋白1（CDH1）从而影响大鼠脑缺血再灌注损伤。建立大鼠短暂性大脑中动脉闭塞模型(MCAO)。给大鼠注射含有 miR-20a 抑制剂、过表达 CDH1 或联合耗尽的 miR-20a 和 CDH1 的慢病毒溶液，以探讨它们在脑 I/R 损伤中的作用。采用RT-qPCR和蛋白质印迹法检测脑组织中氧化应激相关因子、miR-20a、CDH1、核因子-κB（NF-κB）和Nestin的表达。通过在线网站预测miR-20a和CDH1之间的靶关系，并通过荧光素酶活性测定进一步证实。在脑缺血再灌注损伤的大鼠中，脑组织中发现 miR-20a 增加，CDH1 减少。 miR-20a 的减少或 CDH1 的升高会减弱 MCAO 大鼠的行为功能。抑制miR-20a或恢复CDH1可以抑制氧化应激，减轻神经元病理损伤，促进神经元存活，并下调MCAO大鼠脑组织中NF-κB和Nestin的表达。 CDH1被确定为miR-20a的靶基因。本研究阐明下调miR-20a可升高CDH1来保护神经元免受脑缺血再灌注损伤，为脑缺血再灌注损伤的治疗开辟新途径。