Department of Hand Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China.
Department of Plastic and Hand Surgery, Technical University of Munich, Ismaninger Strasse 22, 81675 Munich, Germany.
Life Sci. 2020 Sep 1;256:118022. doi: 10.1016/j.lfs.2020.118022. Epub 2020 Jun 28.
We aim to study the anti-apoptotic effect of microRNA-21-5p (miR-21-5p) in the oxidative stress-induced apoptosis of Schwann cells and the relevant mechanism in this research, laying a foundation for the treatment of peripheral neuropathy (PNP).
The oxidative stress model was established by using hydrogen peroxide (HO). ROS level were detected by DCFH-DA (2,7-Dichlorodi-hydrofluorescein diacetate). Western blot and fluorescence staining were used to detect the apoptosis and autophagy level. The miR-21-5p overexpression model was established by transfection of miR-21-5p mimics into RSC96 cells. Five groups of control group, HO group, HO + chloroquine (CQ) group, HO + miR-21-5p mimics group, and HO + miR-21-5p mimics+rapamycin (RAPA) group were included in our experiment.
Compared with control group, miR-21-5p was decreased in HO-treated RSC96 cells, while autophagy and apoptosis were both promoted. The result revealed that apoptosis was probably triggered by activation of autophagy in HO-treated group. In order to verify the relationship between autophagy and apoptosis more accurately, we used CQ to inhibit autophagy. Compared with HO-treated group, autophagy and apoptosis were both weakened in HO + CQ group. Subsequently, we found the antiapoptotic effect of miR-21-5p in this model, overexpression of miR-21-5p prevented cells from being damaged by oxidative stress, it induced the decrease of PTEN and the level of autophagy, leading to decreased level of apoptosis.
The identified relationship between miR-21-5p, apoptosis, and autophagy promotes us to find a new mechanism to improve the treatment for PNP.
本研究旨在探讨 microRNA-21-5p（miR-21-5p）在氧化应激诱导施万细胞凋亡中的抗凋亡作用及其相关机制，为治疗周围神经病（PNP）奠定基础。
采用过氧化氢（HO）建立氧化应激模型。采用 DCFH-DA（2,7-二氯二氢荧光素二乙酸酯）检测 ROS 水平。采用 Western blot 和荧光染色检测细胞凋亡和自噬水平。通过转染 miR-21-5p 模拟物建立 miR-21-5p 过表达模型。实验分为对照组、HO 组、HO+氯喹（CQ）组、HO+miR-21-5p 模拟物组和 HO+miR-21-5p 模拟物+雷帕霉素（RAPA）组。
与对照组相比，HO 处理的 RSC96 细胞中 miR-21-5p 表达降低，自噬和凋亡均增加。结果表明，HO 处理组可能通过激活自噬诱导细胞凋亡。为了更准确地验证自噬与凋亡之间的关系，我们使用 CQ 抑制自噬。与 HO 处理组相比，HO+CQ 组自噬和凋亡均减弱。随后，我们发现 miR-21-5p 在该模型中的抗凋亡作用，过表达 miR-21-5p 可防止细胞受到氧化应激的损伤，它诱导 PTEN 减少和自噬水平增加，导致凋亡水平降低。
miR-21-5p、凋亡和自噬之间的关系为我们提供了一个新的机制，以改善 PNP 的治疗效果。
