Abstract

The dysregulated microRNAs (miRNAs) are implicated in the malignancy of lupus nephritis (LN). This work aims to analyse the effect and mechanism of miR-146b-5p in lipopolysaccharides (LPS)-induced model of LN in vitro. The serum samples of LN patients and normal volunteers were collected. HK-2 cells were challenged via LPS. miR-146b-5p and interferon-induced protein 35 (IFI35) abundances were detected via quantitative real-time polymerase chain reaction (qRT-PCR) or western blot. The inflammatory response was assessed via inflammatory cytokines levels via qRT-PCR and enzyme-linked immunosorbent assay. Cell apoptosis was analysed via flow cytometry and apoptotic protein levels. The protein levels of JAK1/STAT1 signalling were detected via western blot. The relationship of miR-146b-5p and IFI35 was analysed via bioinformatics and dual-luciferase reporter assays. This study revealed that miR-146b-5p level was declined and IFI35 abundance was elevated in serum of LN patients and LPS-challenged HK-2 cells. Functionally, IFI35 overexpression promoted LPS-caused inflammatory response and cell apoptosis, and knockdown of IFI35 caused an opposite trend. Meanwhile, miR-146b-5p targeted IFI35 to suppress inflammatory response and cell inflammatory response and apoptosis via inactivating the JAK1/STAT1 pathway. MiR-146b-5p suppressed inflammatory response and cell apoptosis by IFI35 mediated-JAK1/STAT1 signalling in HK-2 cells, which provided a new mechanism for understanding the pathogenesis of LN.

摘要

失调的 microRNA (miRNA) 与狼疮性肾炎 (LN) 的恶性肿瘤有关。本工作旨在分析miR-146b-5p在脂多糖（LPS）诱导的LN体外模型中的作用和机制。收集LN患者和正常志愿者的血清样本。HK-2 细胞通过LPS进行攻击。通过定量实时聚合酶链反应 (qRT-PCR) 或蛋白质印迹检测miR-146b-5p 和干扰素诱导的蛋白 35 (IFI35) 丰度。通过qRT-PCR 和酶联免疫吸附测定通过炎症细胞因子水平评估炎症反应。通过分析细胞凋亡流式细胞仪和凋亡蛋白水平。通过蛋白质印迹检测 JAK1/STAT1 信号的蛋白质水平。通过生物信息学和双荧光素酶报告基因分析分析了 miR-146b-5p 和 IFI35 的关系。该研究表明，LN 患者和 LPS 攻击的 HK-2 细胞血清中 miR-146b-5p 水平下降，IFI35 丰度升高。在功能上，IFI35 过表达促进 LPS 引起的炎症反应和细胞凋亡，而 IFI35 的敲低导致相反的趋势。同时，miR-146b-5p靶向IFI35通过抑制炎症反应和细胞炎症反应和细胞凋亡使 JAK1/STAT1 通路失活。MiR-146b-5p通过IFI35介导的-JAK1/STAT1信号在HK-2细胞中抑制炎症反应和细胞凋亡，为理解LN的发病机制提供了新的机制。