miR-30c靶向SOCS1和MDTH调节内/外源性细胞凋亡双通路介导对比剂急性肾损伤的机制研究

Contrast-induced acute kidney injury (CIAKI) is a common complication of cardiovascular interventional therapy. Our preliminary experiments have found that the expression of miR-30c was significantly decreased in CIAKI models of Wistar rats and HK-2 cells, and closely related with kidney injury and apoptosis of renal tubular epithelial cells, accompanying with the activation of SOCS1-mediated intrinsic apoptosis pathway (Bcl-2/Bax-Caspase-9) and MDTH-mediated extrinsic apoptosis pathway (FADD-Caspase-8). Bioinformatics analysis showed that both SOCS1 and MDTH are candidate target genes for miR-30c.Therefore, we hypothesized that the nephrotoxicity of contrast agents down-regulates the expression of miR-30c, which in turn activates both intrinsic and extrinsic apoptosis pathways by targeting SOCS1 and MDTH, leading to apoptosis of renal tubular epithelial cells and acute kidney injury. This project aims to further detect the changes of SOCS1, MDTH, intrinsic/extrinsic apoptosis pathways, renal tubular epithelial cell apoptosis, and renal damage after exogenously up-regulating or inhibiting of miR-30c expression in CIAKI rats and HK-2 cells. We also try to confirm the relations and binding sites between miR-30c and SOCS1/MDTH using dual luciferase reporter assay. Our study is expected to clarify the role and molecular mechanism of miR-30c in CIAKI, and provides new insights for the prevention and treatment of CIAKI.

对比剂急性肾损伤（CIAKI）是心血管介入治疗的常见并发症。预实验发现，miR-30c表达下调与大鼠CIAKI严重程度及HK-2细胞凋亡密切相关，伴随SOCS1介导的内源性细胞凋亡通路Bcl-2/Bax-Caspase-9和MDTH介导的外源性细胞凋亡通路FADD-Caspase-8激活。生物信息学分析显示SOCS1和MDTH均为miR-30c的候选靶基因。据此我们推测：对比剂肾毒性使miR-30c表达下调，继而靶向SOCS1和MDTH分别调节内/外源性凋亡通路，引起肾小管上皮细胞凋亡，最终导致CIAKI。本项目拟在预实验基础上，外源性上调或抑制miR-30c表达，检测靶基因、内/外源性凋亡通路、HK-2细胞凋亡、肾脏病理损伤等变化；并采用双荧光素酶报告基因分析法确定miR-30c对SOCS1和MDTH的靶向调控位点，以阐明miR-30c在CIAKI中的作用机制，为防治CIAKI提供新思路

对比剂诱导的急性肾损伤（CIAKI）是一种严重的肾功能衰竭，其发病机制尚不清楚。microRNA（miR）-30c在肾脏疾病中起着关键作用。然而，miR-30c在CIAKI中的作用机制尚不清楚。本研究旨在通过动物实验观察CIAKI大鼠模型中miR-30c的表达，并通过动物和细胞实验明确miR-30是否能改善CIAKI发生。我们发现miR-30c在CIAKI的大鼠模型和细胞模型中显著下调。在患有CIAKI的大鼠中，注射miR-30c 增加了肾脏组织中的含量，并改善了血浆肌酐、组织损伤和细胞凋亡。此外，miR-30c的过表达减少了对比剂诱导的HK-2细胞凋亡。进一步的机制研究，采用双荧光素酶报告基因测定来确定miR-30c和SOCS1之间的关系。进行了SOCS1的功能挽救实验，以评估其在CIAKI中的作用。MiR-30c靶向SOCS1，SOCS1的上调逆转了miR-30c过表达在omnipaque诱导的HK-2细胞凋亡中的保护作用。过表达miR-30c通过靶向SOCS1抑制内源性细胞凋亡并减弱CIAKI。这项研究为miR-30c作为CIAKI防治手段提供新的科学依据。