Luan Yonggang, Zhang Xiaoli, Zhang Yongli, Dong Yubin
Department of Neonatal Intensive Care Unit, Zhoukou Central HospitalZhoukou, China.
Front Cell Neurosci. 2017 Sep 22;11:285. doi: 10.3389/fncel.2017.00285. eCollection 2017.
MicroRNA (miR)-210 is the most consistently and predominantly up-regulated miR in response to hypoxia in multiple cancer cells. The roles of miR-210 in rat adrenal gland pheochromocytoma (PC-12) cells remain unknown. We aimed to explore the possible effect of miR-210 in neonatal brain injury. We explored the potential molecular mechanism by using PC-12 cells under hypoxia. Scramble miRs, miR-210 mimic, miR-210 inhibitor or its negative control were respectively transfected into PC-12 cells. Cell viability, migration, invasion and apoptosis were also assessed to evaluate hypoxia-induced cell injury. The expression level of miR-210 was identified by quantitative real-time polymerase chain reaction (qRT-PCR) analysis. Apoptosis-related protein expression as well as key kinases in the phosphatidylinositol 3-kinase (PI3K)/AKT/mammalian target of rapamycin (mTOR) signal pathway was studied by Western blot analysis. Hypoxia suppressed cell viability, migration and invasion, but promoted apoptosis through activation of mitochondrial- and caspase-dependent pathways. Hypoxia markedly induced up-regulation of miR-210 in PC-12 cells. Overexpression of miR-210 protected PC-12 cells against hypoxia-induced injury. Bcl-2 adenovirus E1B 19 kDa-interacting protein 3 (BNIP3) was proven to be a target gene of miR-210 in PC-12 cells. miR-210 overexpression ameliorated the hypoxia-induced injury in PC-12 cells by down-regulating BNIP3. Hypoxia-induced alterations of key kinases in the PI3K/AKT/mTOR signal pathway were affected by aberrant expression of BNIP3. These findings suggested that miR-210 protected PC-12 cells against hypoxia-induced injury by targeting BNIP3, involving the PI3K/AKT/mTOR signal pathway.
微小RNA（miR）-210是多种癌细胞中对缺氧反应最持续且上调最显著的miR。miR-210在大鼠肾上腺嗜铬细胞瘤（PC-12）细胞中的作用尚不清楚。我们旨在探讨miR-210在新生儿脑损伤中的可能作用。我们利用缺氧条件下的PC-12细胞探索其潜在分子机制。将乱序miR、miR-210模拟物、miR-210抑制剂或其阴性对照分别转染到PC-12细胞中。还评估了细胞活力、迁移、侵袭和凋亡以评估缺氧诱导的细胞损伤。通过定量实时聚合酶链反应（qRT-PCR）分析鉴定miR-210的表达水平。通过蛋白质免疫印迹分析研究凋亡相关蛋白表达以及磷脂酰肌醇3激酶（PI3K）/蛋白激酶B（AKT）/雷帕霉素靶蛋白（mTOR）信号通路中的关键激酶。缺氧抑制细胞活力、迁移和侵袭，但通过激活线粒体和半胱天冬酶依赖性途径促进凋亡。缺氧显著诱导PC-12细胞中miR-210上调。miR-210过表达保护PC-12细胞免受缺氧诱导的损伤。已证实Bcl-2腺病毒E1B 19 kDa相互作用蛋白3（BNIP3）是PC-12细胞中miR-210的靶基因。miR-210过表达通过下调BNIP3改善PC-12细胞中的缺氧诱导损伤。BNIP3的异常表达影响了缺氧诱导的PI3K/AKT/mTOR信号通路中关键激酶的变化。这些发现表明，miR-210通过靶向BNIP3保护PC-12细胞免受缺氧诱导的损伤，涉及PI3K/AKT/mTOR信号通路。
