Key Laboratory of Endemic and Ethnic Diseases, Ministry of Education, School of Basic Medical Science, Guizhou Medical University, Guiyang, Guizhou 550004, P.R. China.
Laboratory of Reproductive Medicine, Department of Physiology, Nanjing Medical University, Nanjing, Jiangsu 210029, P.R. China.
Int J Mol Med. 2020 Sep;46(3):1051-1062. doi: 10.3892/ijmm.2020.4642. Epub 2020 Jun 16.
MicroRNAs (miRNAs/miRs) have been reported to affect ischemia/reperfusion (I/R)‑induced cerebral damage. miRNAs cause post‑transcriptional gene silencing by binding to the protein‑coding sequence (CDS) of mRNAs. Seipin has a potential role in regulating autophagic flux. The present study investigated the involvement of miR‑187‑3p in Seipin expression, autophagic flux and apoptosis in vitro, as well as the underlying mechanism, using PC12 cells exposed to oxygen‑glucose deprivation/reoxygenation (OGD/R), which mimicked the process of I/R. In comparison with control PC12 cells, OGD/R caused an increase in the level of miR‑187‑3p and a decrease in Seipin protein levels without changes in the level of Seipin mRNA. Using bioinformatics analysis, it was identified that miR‑187‑3p could bind to the CDS of Seipin. miR‑187‑3p inhibitor attenuated the reduction in Seipin protein expression in OGD/R‑treated PC12 cells. Following OGD/R, autophagic flux was reduced and apoptosis was enhanced, which were attenuated by inhibition of miR‑187‑3p. Compared with OGD/R‑treated PC12 cells, Seipin knockdown further impaired autophagic flux and promoted neuronal apoptosis, which were insensitive to inhibition of miR‑187‑3p. Furthermore, treatment with miR‑187‑3p inhibitor could decrease the infarction volume in a rat model of middle cerebral artery occlusion/reperfusion. The present findings indicated that miR‑187‑3p inhibitor attenuated ischemia‑induced cerebral damage by rescuing Seipin expression to improve autophagic flux.
微小 RNA（miRNA/miRs）已被报道可影响缺血/再灌注（I/R）引起的脑损伤。miRNA 通过与 mRNA 的编码序列（CDS）结合来实现基因的转录后沉默。Seipin 在调节自噬流中具有潜在作用。本研究通过使用氧葡萄糖剥夺/复氧（OGD/R）处理的 PC12 细胞（模拟 I/R 过程），探讨了 miR-187-3p 在 Seipin 表达、自噬流和细胞凋亡中的作用及其潜在机制。与对照 PC12 细胞相比，OGD/R 导致 miR-187-3p 水平升高，Seipin 蛋白水平降低，而 Seipin mRNA 水平不变。通过生物信息学分析，发现 miR-187-3p 可与 Seipin 的 CDS 结合。miR-187-3p 抑制剂可减轻 OGD/R 处理的 PC12 细胞中 Seipin 蛋白表达的减少。OGD/R 后，自噬流减少，细胞凋亡增强，而 miR-187-3p 抑制剂可减弱这种作用。与 OGD/R 处理的 PC12 细胞相比，沉默 Seipin 进一步损害了自噬流，并促进了神经元凋亡，而 miR-187-3p 抑制剂对其无作用。此外，miR-187-3p 抑制剂的治疗可减少大脑中动脉闭塞/再灌注大鼠模型中的梗死体积。本研究结果表明，miR-187-3p 抑制剂通过挽救 Seipin 表达来改善自噬流，从而减轻缺血引起的脑损伤。
