Yang Shuying, Wang Yongqiang, Gao Hongmei, Wang Bing
Intensive Care Unit, Tianjin First Central Hospital, Tianjin 300192, P.R. China.
Exp Ther Med. 2018 Feb;15(2):2081-2087. doi: 10.3892/etm.2017.5644. Epub 2017 Dec 15.
The aim of the present study was to explain the mechanism of miR-30a-3p overexpression in sepsis-induced cell apoptosis and . For the cell experiments, H9c2 cells were divided into three groups, including the untreated normal control (NC), lipopolysaccharide (LPS)-treated and miRNA (treated with LPS and transfection with miRNA-30a-3p) groups. The cell proliferation and apoptosis were evaluated by MTT assay and flow cytometry, respectively. The relative protein expression levels were measured by western blot assay. In the experiment, a sepsis rat model was established by intraperitoneal injection of LPS. Sprague Dawley rats were divided into three groups, including the NC, LPS-injected and miRNA (in which model rats were injected with miR-30a-3p vector at the caudal vein) groups. The myocardial morphology in different groups was observed by hematoxylin and eosin staining. In addition, tissue apoptosis and protein expression levels were evaluated by TUNEL and western blot assay, respectively. The results of cell experiments indicated that the cell proliferation rate was significantly increased and the cell apoptosis rate was significantly downregulated in the miR-30a-3p group compared with the LPS group (both P<0.05). The relative protein expression of phosphatase and tensin homolog (PTEN) was markedly decreased in the miRNA group compared with the LPS group, while the levels of phosphoinositide 3-kinase (PI3K) and protein kinase B (AKT) were significantly increased in the miRNA group (all P<0.05). In the experiments, the myocardial morphology of the miRNA group was improved compared with that of the LPS group. Compared with the LPS group, cell apoptosis in the miRNA group was significantly downregulated (P<0.05), while the relative protein levels (PTEN, PI3K and AKT) in the tissues were also significantly altered (P<0.05). In conclusion, miR-30a-3p overexpression may improve the sepsis-induced cell apoptosis and via the PTEN/PI3K/AKT signaling pathway.
本研究的目的是解释脓毒症诱导细胞凋亡过程中miR-30a-3p过表达的机制。在细胞实验中，H9c2细胞被分为三组，包括未处理的正常对照组（NC）、脂多糖（LPS）处理组和miRNA组（用LPS处理并转染miR-30a-3p）。分别通过MTT法和流式细胞术评估细胞增殖和凋亡情况。通过蛋白质免疫印迹法检测相关蛋白表达水平。在动物实验中，通过腹腔注射LPS建立脓毒症大鼠模型。将Sprague Dawley大鼠分为三组，包括NC组、注射LPS组和miRNA组（模型大鼠经尾静脉注射miR-30a-3p载体）。通过苏木精-伊红染色观察不同组的心肌形态。此外，分别通过TUNEL法和蛋白质免疫印迹法评估组织凋亡和蛋白表达水平。细胞实验结果表明，与LPS组相比，miR-30a-3p组细胞增殖率显著升高，细胞凋亡率显著下调（均P<0.05）。与LPS组相比，miRNA组中磷酸酶和张力蛋白同源物（PTEN）的相对蛋白表达明显降低，而miRNA组中磷脂酰肌醇3激酶（PI3K）和蛋白激酶B（AKT）的水平显著升高（均P<0.05）。在动物实验中，与LPS组相比，miRNA组的心肌形态有所改善。与LPS组相比，miRNA组细胞凋亡明显下调（P<0.05），同时组织中的相关蛋白水平（PTEN、PI3K和AKT）也发生了显著变化（P<0.05）。总之，miR-30a-3p过表达可能通过PTEN/PI3K/AKT信号通路改善脓毒症诱导的细胞凋亡。
