Qi Yinbao, Qian Ruobing, Jia Li, Fei Xiaorui, Zhang Dong, Zhang Yiming, Jiang Sen, Fu Xianming
Department of Nuerosurgery, Shandong University , Jinan, Shandong Province, P. R. China.
Department of Neurosurgery, the First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China , Hefei, Anhui Province, P. R. China.
Cell Cycle. 2020 Jun;19(11):1298-1313. doi: 10.1080/15384101.2020.1749472. Epub 2020 Apr 19.
The effects of microRNAs (miRNAs) have been identified in epilepsy (Ep) in recent years, our research was focused on the functions of miR-494 in Ep and its inner mechanisms.
The Ep modeled rats induced by lithium chloride-pilocarpine were treated with agomir-miR-494 or RIPK1-siRNA. The pathology of rat hippocampal tissues was observed. Expression of miR-494, receptor-interacting protein kinase 1 (RIPK1) and nuclear factor-kappaB (NF-κB) p65 was assessed by RT-qPCR and Western blot analysis. The hippocampal neurons of epileptic rats were successfully modeled, which were transfected with miR-494 mimics or RIPK1-siRNA to determine neurons' proliferation ability and cell apoptosis. The target relation between miR-494 and RIPK1 was measured by bioinformatics website and dual luciferase gene reporter assay.
The expression of miR-494 was reduced, while the expression of RIPK1 and NF-κB p65 was amplified in hippocampus of Ep rats. Elevated miR-494 repressed the expression of RIPK1 to ameliorate the hippocampal neuron injury, accelerate neuronal proliferation, and restrain neuronal apoptosis via inactivating the NF-κB signaling pathway, causing a deceleration of Ep development. Furthermore, amplified RIPK1 was able to reverse the amelioration of neuronal injury in Ep rats which was contributed by upregulated miR-494.
We found in this study that elevated miR-494 repressed RIPK1, causing an inactivation of the NF-κB signaling pathway and acceleration of cell proliferation, and suppression of apoptosis of hippocampal neurons in Ep rats, thereby attenuating the neuron injury and Ep development. Our research may provide novel targets for the therapy of Ep.
近年来已确定微小RNA（miRNA）在癫痫（Ep）中发挥作用，本研究聚焦于miR-494在癫痫中的功能及其内在机制。
用氯化锂-匹罗卡品诱导癫痫模型大鼠，分别给予agomir-miR-494或RIPK1-siRNA进行处理。观察大鼠海马组织病理学变化。采用RT-qPCR和蛋白质免疫印迹分析评估miR-494、受体相互作用蛋白激酶1（RIPK1）和核因子-κB（NF-κB）p65的表达。成功构建癫痫大鼠海马神经元模型，转染miR-494模拟物或RIPK1-siRNA，以确定神经元的增殖能力和细胞凋亡情况。通过生物信息学网站和双荧光素酶基因报告基因检测法检测miR-494与RIPK1之间的靶向关系。
癫痫大鼠海马中miR-494表达降低，而RIPK1和NF-κB p65表达升高。上调miR-494可抑制RIPK1表达，通过使NF-κB信号通路失活来改善海马神经元损伤、促进神经元增殖并抑制神经元凋亡，从而减缓癫痫发展。此外，增强RIPK1能够逆转上调miR-494对癫痫大鼠神经元损伤的改善作用。
本研究发现上调miR-494可抑制RIPK1，导致NF-κB信号通路失活，促进细胞增殖，抑制癫痫大鼠海马神经元凋亡，从而减轻神经元损伤和癫痫发展。本研究可能为癫痫治疗提供新的靶点。
