IRF4通过JAK/STAT信号通路调控糖尿病肾病炎症进展

IRF4 regulates inflammation progression in diabetic nephropathy through JAK/STAT signaling pathway

目的筛选分析糖尿病肾病(DN)的差异表达基因(DEG),探讨IFN调节因子4(IRF4)在DN中的作用机制,为DN治疗寻找潜在的分子靶点。方法经基因表达综合(GEO)数据库下载GSE142025数据集[包含对照组9例与进展期DN(aDN)组21例],进行DEG筛选,行基因集富集分析(GSEA)示DEG参与的分子生物学过程。使用String及Cytoscape软件可视化DEG蛋白质相互作用网络,定量逆转录PCR(RT-qPCR)和过碘酸-希夫(PAS)染色及链霉菌抗生物素蛋白-过氧化物酶(SP)染色并进一步验证主要DEG在6例DN肾组织(DN组)和6例肿瘤切除术后癌旁正常肾组织(NC组)中的表达。结果GEO数据库筛选出1213个差异表达mRNA,其中684个上调、529个下调。GSEA及京都基因和基因组百科全书分析显示aDN组DEG在酪氨酸激酶/信号转导及转录激活因子信号通路、趋化因子信号通路、Fcγ受体介导巨噬细胞的吞噬作用信号通路、白细胞跨内皮迁移、T细胞受体信号通路明显富集。DN组肾组织中IRF4、信号淋巴细胞活化分子6和IL-2受体α亚基mRNA相对表达量均高于NC组肾组织(P均<0.001),PAS及SP染色结果与RT-qPCR一致。结论GSEA功能富集显示炎症相关通路活跃,而IRF4在DN组织中作为中枢基因表达上调,其可能参与高活跃炎症通路促进DN进展。

Objective To screen and analyze the differentially-expressed genes(DEGs)of diabetic nephropathy(DN)by bioinformatics methods,aiming to explore the mechanism of IRF4 in DN,and to find potential molecular targets of DN.Methods The GSE142025 dataset was downloaded from the GEO database,including 9 cases in normal control group and 21 cases in advanced DN(aDN)group,and the DEGs were screened.The GSEA enrichment revealed the molecular biological process of the DEGs.Protein-protein interaction networks of DEG were visualized using String and Cytoscape software.The relative expression levels of major DEGs in six DN renal tissues(DN group)and six normal renal tissues after tumor resection(NC group)were verified using RT-qPCR,PAS and SP staining.Results GEO data analysis revealed 1213 differentially-expressed mRNA,of which 684 were upregulated and 529 were down-regulated.The GSEA and KEGG pathway enrichment of DEGs showed that the DEGs in the DN group were significantly enriched in the JAK/STAT signaling pathway,chemokine signaling pathway,Fcγreceptor-mediated phagocytosis of macrophages signaling pathway,leukocyte transendothelial migration signaling pathway and T cell receptor signaling pathway.The relative expression levels of IRF4,signal lymphocyte activating molecule 6 and IL-2 receptorαsubunit mRNA in the DN group were significantly higher compared with those in the NC group(all P<0.001).The PAS and SP staining results were consistent with those of RT-qPCR.Conclusion The GSEA enrichment pathways show that the inflammatory pathway is significantly active,and the expression of IRF4 as a hub gene is significantly up-regulated in the DN tissues,which may be involved in the highly-active inflammatory pathway and promote the progression of inflammation in DN.