miR-124-3p和自噬在LPS致小胶质细胞死亡中的作用机制研究

Role of miR-124-3p and autophagy in LPS induced microglia cell death

目的:探讨miR-124-3p 和细胞自噬在脂多糖(lipopolysaccharides, LPS)引起小胶质细胞死亡中的作用,以及miR-124-3p 与自噬的相互关系。方法:离体条件下,使用1 μg/mL LPS 处理BV2 细胞,采用噻唑蓝检测BV2 细胞活力,实时定量荧光PCR检测miR-124-3p 表达水平,Western Blot检测LC3B蛋白表达水平。应用慢病毒载体过表达miR-124-3p,观察miR-124-3p对LPS 引起BV2 细胞活力以及自噬的影响。0.1 μmol/L雷帕霉素预处理BV2 细胞,观察自噬对LPS 引起BV2 细胞活力及miR-124-3p水平变化的影响。结果: LPS 处理BV2 细胞后,BV2 细胞活力显著降低,且miR-124-3p 表达下调,细胞自噬水平显著上升。过表达miR-124-3p能有效抑制由LPS 引起的BV2 细胞活力降低,并有效抑制LPS 引起的细胞自噬。雷帕霉素预处理BV2 细胞,能显著缓解由LPS 引起的BV2 细胞活力和miR-124-3p表达降低。结论: LPS可以通过下调miR-124-3p表达,影响小胶质细胞存活。同时,自噬也可在一定程度上负反馈调节miR-124-3p 表达,影响BV2 细胞存活。

Objective : To investgate the effect of miR-124-3p and autophagy in microglia cell death induced by lipopolysaccharides( LPS) and the interaction between miR-124-3p and autophagy. Methods : 3-(4, 5-dimethyl-2-thiazolyl)-2, 5-diphenyl-2-H-tetrazolium bromide assay was used to detect the BV2 cell viability with 1 μg/mL LPS treatment in vitro. MiR-124-3p expression was performed by real time PCR and LC3B expression was detected by Western Blot. Mimic miR-124-3p lentivirus was constructed to demonstrate the effect of miR-124-3p in microglia cell death induced by LPS. Pre-treatment of BV-2 cells with 0.1 μmol/L Rapamycin illuminated the effect of autophagy in microglia cell death induced by LPS and the relationship between miR-124-3p and autophagy. Results : LPS significantly inhibited BV2 microglia cell viability and miR-124-3p expression. LPS significantly induced BV2 microglia autophagy. MiR-124-3p inhibited the BV2 microglia cell death and the increase of autophagy induced by LPS. Rapamycin treatment in advanced rescued BV2 microglia cell death and decrease of miR-124-3p. Conclusion : LPS inhibited BV2 microglia cell viability via miR-124-3p. The negative feedback regulation of autophagy affected BV2 microglia cell viability and miR-124-3p expression to some extent.