Department of endocrinology, The Affiliated Lianyungang Hospital of Xuzhou Medical University, The First People's Hospital of Lianyungang, The Affiliated Hospital of Kangda College of Nanjing Medical University Lianyungang Clinical College of Nanjing Medical University, Lianyungang, China.
J Cell Physiol. 2019 Jul;234(7):11646-11653. doi: 10.1002/jcp.27822. Epub 2019 Jan 13.
To investigate the role of miR-424 in diabetic nephropathy (DN) and its relationship with Rictor in mammalian target of rapamycin (mTOR) C2/Akt signaling.
The western blot analysis and real-time polymerase chain reaction were used to determine the differential expression of Rictor, mTOR, and miR-424 in DN rats. The upregulation of miR-424 was achieved by caudal vein injection of miR-424 mimics. The renal lesion was evaluated by hematoxylin-eosin staining (H&E) and periodic acid schiff staining. The dual-luciferase reporter assay was conducted to determine the binding target of miR-424. The effect of miR-424 upregulation on apoptosis was detected by the terminal deoxynucleotidyl transferase-mediated 2-Deoxyuridine-5-Triphosphate (dUTP) nick-end labeling assay and western blot analysis.
A significantly lower expression of miR-424 and a significantly higher expression of Rictor and mTOR were found in renal tissues of DN rats. The upregulation of miR-424 improved renal lesion and DN symptoms of blood glucose level, urine protein level, body weight, creatinine level, blood urea nitrogen, and KW/BW ratio. The upregulation of miR-424 could significantly reduce apoptosis rates of tissue cells by decreasing the expression levels of caspase-3 and Bax as well as increasing the level of Bcl-2. Furthermore, Rictor was the direct target for miR-424, and upregulation of miR-424 inhibited Rictor through Akt signaling in renal tissue of DN rats and high-glucose-treated human glomerular mesangial cells.
miR-424 contributes to alleviating the symptoms in DN rat models by targeting Rictor through mTORC2/Akt signaling.
研究 miR-424 在糖尿病肾病 (DN) 中的作用及其与哺乳动物雷帕霉素靶蛋白 (mTOR) C2/Akt 信号通路中 Rictor 的关系。
采用 Western blot 分析和实时聚合酶链反应检测 DN 大鼠中 Rictor、mTOR 和 miR-424 的差异表达。通过尾静脉注射 miR-424 模拟物上调 miR-424 的表达。通过苏木精-伊红 (H&E) 染色和过碘酸希夫 (PAS) 染色评估肾损伤。通过双荧光素酶报告实验确定 miR-424 的结合靶标。通过末端脱氧核苷酸转移酶介导的 2-脱氧尿苷 5-三磷酸 (dUTP) 缺口末端标记 (TUNEL) 检测和 Western blot 分析检测 miR-424 上调对细胞凋亡的影响。
DN 大鼠肾组织中 miR-424 表达明显下调，Rictor 和 mTOR 表达明显上调。miR-424 的上调改善了肾病变和 DN 症状，如血糖水平、尿蛋白水平、体重、肌酐水平、血尿素氮和 KW/BW 比值。miR-424 的上调通过降低组织细胞中 caspase-3 和 Bax 的表达水平以及增加 Bcl-2 的水平，显著降低细胞凋亡率。此外，Rictor 是 miR-424 的直接靶标，上调 miR-424 通过 Akt 信号通路抑制 DN 大鼠肾组织和高糖处理的人肾小球系膜细胞中的 Rictor。
miR-424 通过靶向 mTORC2/Akt 信号通路中的 Rictor，有助于缓解 DN 大鼠模型的症状。
