MicroRNA-21 protects against cardiac hypoxia/reoxygenation injury by inhibiting excessive autophagy in H9c2 cells via the Akt/mTOR pathway.
MicroRNA-21 protects against cardiac hypoxia/reoxygenation injury by inhibiting excessive autophagy in H9c2 cells via the Akt/mTOR pathway.
复制标题
MicroRNA-21 通过 Akt/mTOR 通路抑制 H9c2 细胞中的过度自噬，从而防止心脏缺氧/复氧损伤
DOI：
10.1111/jcmm.12990
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发表时间：
2017-03
影响因子：
5.3
通讯作者：
Huang W
中科院分区：
文献类型：
--
作者：
Huang Z;Wu S;Kong F;Cai X;Ye B;Shan P;Huang W
MicroRNA和自噬在心脏缺氧/复氧（H/R）诱导的损伤中起关键作用。在这里，我们研究了miR-21在调节自噬中的功能，并确定了涉及的潜在分子机制。为了确定miR-21在调节自噬中的作用，将H9 c2细胞分为以下六组：对照组、H/R组、（miR-21+ H/R）组、（miR-21阴性对照+ H/R）组、（BEZ 235 + H/R）组和（miR-21+ BEZ 235 + H/R）组。细胞经历缺氧1小时和复氧3小时。使用细胞计数试剂盒-8评价细胞功能，并通过蛋白质印迹法分析细胞凋亡。Western blotting和透射电镜观察细胞自噬。我们发现，在H/R损伤期间，H9 c2细胞中miR-21表达下调，自噬显著增加。miR-21与miR-21前体的过表达显著抑制自噬活性并减少凋亡，伴随着AKT/mTOR通路的激活。此外，用新型Akt/mTOR双重抑制剂BEZ 235处理导致自噬和凋亡显著增加。然而，我们发现miR-21介导的细胞凋亡和自噬抑制部分不依赖于Akt/mTOR激活，正如miR-21和BEZ 235处理的细胞所证明的那样。我们发现miR-21可以抑制H/R诱导的自噬和凋亡，这可能至少部分由Akt/mTOR信号通路介导。
MicroRNAs and autophagy play critical roles in cardiac hypoxia/reoxygenation (H/R)‐induced injury. Here, we investigated the function of miR‐21 in regulating autophagy and identified the potential molecular mechanisms involved. To determine the role of miR‐21 in regulating autophagy, H9c2 cells were divided into the following six groups: control group, H/R group, (miR‐21+ H/R) group, (miR‐21‐negative control + H/R) group, (BEZ235+ H/R) group and (miR‐21+ BEZ235+ H/R) group. The cells underwent hypoxia for 1 hr and reoxygenation for 3 hrs. Cell count kit‐8 was used to evaluate cell function and apoptosis was analysed by Western blotting. Western blotting and transmission electron microscopy were used to investigate autophagy. We found that miR‐21 expression was down‐regulated, and autophagy was remarkably increased in H9c2 cells during H/R injury. Overexpression of miR‐21 with a miR‐21 precursor significantly inhibited autophagic activity and decreased apoptosis, accompanied by the activation of the AKT/mTOR pathway. In addition, treatment with BEZ235, a novel dual Akt/mTOR inhibitor, resulted in a significant increase in autophagy and apoptosis. However, we found that miR‐21‐mediated inhibition of apoptosis and autophagy was partly independent of Akt/mTOR activation, as demonstrated in cells treated with both miR‐21 and BEZ235. We showed that miR‐21 could inhibit H/R‐induced autophagy and apoptosis, which may be at least partially mediated by the Akt/mTOR signalling pathway.