miR-485-5p suppresses Schwann cell proliferation and myelination by targeting cdc42 and Rac1
miR-485-5p suppresses Schwann cell proliferation and myelination by targeting cdc42 and Rac1
复制标题
DOI：
10.1016/j.yexcr.2019.111803
复制
发表时间：
2020-03-01
影响因子：
3.7
通讯作者：
Wu, Guangzhi
中科院分区：
文献类型：
--
作者：
Zhang, Zhan;Li, Xuyang;Wu, Guangzhi
雪旺细胞是周围神经系统的重要组成部分，在周围神经损伤后起着重要作用。近年来，miR-485- 5 p在神经系统疾病中的作用被发现。然而，miR-485- 5 p和周围神经损伤的参与仍然未知。采用小鼠坐骨神经夹伤模拟周围神经损伤，实时荧光定量PCR检测坐骨神经断端miR-485- 5 p的表达。BrdU法检测转染miR-485- 5 p模拟物和miR-485- 5 p抑制剂后雪旺细胞的增殖情况。通过评估环磷酸腺苷（cAMP）诱导的髓鞘相关蛋白（包括Krox 20和MBP）的水平以及经由用抗MBP抗体的免疫染色的雪旺细胞和背根神经节（DRG）神经元的共培养来确定miR-485- 5 p对雪旺细胞髓鞘形成的影响。通过生物信息学分析、荧光素酶报告基因分析、实时荧光定量PCR和Western blot分析miR-485- 5 p的调控机制。我们发现miR-485- 5 p在神经损伤后表达下调。miR-485- 5 p模拟物显著抑制Schwann细胞的增殖和cAMP诱导的Krox 20和MBP表达水平。相反，miR-485.5p抑制剂促进了雪旺细胞中的这些变化。此外，miR-485- 5 p抑制剂升高MBP阳性有髓纤维。Cdc 42和Racl是施旺细胞中miR-485- 5 p的靶点。下调cdc 42可逆转miR-485- 5 p抑制剂对雪旺细胞增殖的影响。降低Racl表达减弱了miR-4855 p沉默对雪旺细胞髓鞘形成的影响。总之，本研究表明miR-485.5p通过靶向cdc 42和Rac 1抑制Schwann细胞的增殖和髓鞘形成。为周围神经损伤的治疗提供了一种新的方法。
Schwann cells, a crucial element in peripheral nervous system, play important roles after peripheral nerve injury. In recent years, the role of miR-485-5p has been discovered in neurological diseases. However, the involvement of miR-485-5p and peripheral nerve injury remains unknown. Mice were subjected to sciatic nerve crush to mimic peripheral nerve injury and the expression of miR-485-5p was detected in sciatic nerve stumps by realtime PCR. BrdU assay was used to analyze the proliferation of Schwann cells after transfecdon with miR-485-5p mimic and miR-485-5p inhibitor. The effect of miR-485-5p on Schwann cell myelination was determined by evaluating levels of cyclic adenosine monophosphate (cAMP)-induced myelin-associated proteins, including Krox20 and MBP, as well as the coculture of Schwann cells and dorsal root ganglion (DRG) neurons via immunostaining with anti-MBP antibodies. The regulation mechanism of miR-485-5p was measured by bioinformatics analysis, luciferase reporter assay, and real-time PCR and Western blot. We found miR-485-5p expression was downregulated post nerve injury. miR-485-5p mimic significantly suppressed the proliferation and cAMP-induced expression levels of Krox20 and MBP in Schwann cells. Conversely, miR-485.5p inhibitor promoted these changes in Schwann cells. Also, miR-485-5p inhibitor elevated MBP-positive myelinated fibers. Cdc42 and Racl are targets of miR-485-5p in Schwann cells. Downregulation of cdc42 reversed the effect of miR-485-5p inhibitor on the proliferation of Schwann cells. And reducing Racl expression attenuated the effect of miR-4855p silencing on Schwann cell myelination. In conclusion, this study indicated that miR-485.5p suppressed the proliferation and myelination of Schwann cells via targeting cdc42 and Rac1. Which may provide a novel method for the treatment of peripheral nerve injury.