MicroRNA-193b-3p alleviates focal cerebral ischemia and reperfusion-induced injury in rats by inhibiting 5-lipoxygenase expression

Autor: Jiahua Zhang, Xiaodan Tan, Weiming Du, Junqing Yang, Yuke Li, Congli Hu, Jianjun Zhong, Hong Wang, Haifeng Huang, Zhihao Chen, Hui Xia, Miaomiao Li, Yang Yang, Zhe Peng, Ying Luo
Rok vydání: 2020
Předmět:
Zdroj: Experimental Neurology. 327:113223
ISSN: 0014-4886
Popis: Aims Ischemic stroke has become one of the main causes of death worldwide. MicroRNAs (miRNAs) have been implicated in cerebral ischemia-reperfusion (I/R) injury and could serve as therapeutic targets. 5-Lipoxygenase (5-LOX) is a key enzyme in the biosynthesis of leukotrienes and has been implicated in inflammatory central nerve system disorders. The objective of this study was to explore the neuroprotective effects of miR-193b-3p against focal cerebral I/R injury in rats by regulating 5-LOX expression. Methods and materials Adult male Sprague-Dawley rats were subjected to transient middle cerebral artery occlusion and reperfusion injury. The level of miR-193b-3p expression was observed in the rat cortical peri-infarct region after focal cerebral I/R injury. Bioinformatics analysis was used to predict the binding sites of miR-193b-3p, and a dual-luciferase reporter gene assay was applied to verify the potential interaction between 5-LOX mRNA and miR-193b-3p. Then, rats were injected with a miR-193b-3p agomir (modified and enhanced mimic) or antagomir (modified and enhanced inhibitor) in the right lateral ventricle of the brain. Neurological deficit scores, infarct volumes, neuron damage and 5-LOX enzymatic activity and expression were measured. In an in vitro experiment, cultured PC12 cells were exposed to oxygen–glucose deprivation and reperfusion (OGD/R). OGD/R-induced cells were treated with a miR-193b-3p mimic or inhibitor and 5-LOX siRNA. Cell viability, lactate dehydrogenase release, apoptosis rate and 5-LOX expression were evaluated. Results The level of miR-193b-3p expression was increased in the cortical peri-infarct region of rats with cerebral focal I/R injury. The results of the dual-luciferase reporter gene assay showed that a miR-193b-3p binding site was located in the 3′ untranslated region (3’UTR) of 5-LOX mRNA. Neurological deficit scores, infarct volumes and neuronal injury were alleviated by miR-193b-3p agomir treatment but aggravated by miR-193b-3p antagomir. Furthermore, leukotriene B4, cysteinyl-leukotrienes and 5-LOX expression in the cortical peri-infarct region of rats with focal cerebral I/R injury were also downregulated by miR-193b-3p agomir treatment but upregulated by miR-193b-3p antagomir. In PC12 cells, miR-193b-3p mimic significantly decreased OGD/R-induced cell death and reduced lactate dehydrogenase release and 5-LOX expression. In contrast, miR-193b-3p inhibitor exacerbated OGD/R-induced injury in PC12 cells. Additionally, the in vitro effects of miR-193b-3p inhibitor on OGD/R-induced cell injury were partially reversed by 5-LOX siRNA treatment. Conclusion MiR-193b-3p has a potentially neuroprotective effect on focal cerebral I/R-induced injury by inhibiting 5-LOX expression.
Databáze: OpenAIRE