Background Diabetic kidney disease (DKD) is the leading cause of death in people with type 2 diabetes mellitus (T2DM). The main objective of this study is to find the potential biomarkers for DKD. Materials and Methods Two datasets (GSE86300 and GSE184836) retrieved from Gene Expression Omnibus (GEO) database were used, combined with our RNA sequencing (RNA-seq) results of DKD mice (C57 BLKS-32w db/db) and non-diabetic (db/m) mice for further analysis. After processing the expression matrix of the three sets of data using R software “Limma”, differential expression analysis was performed. The significantly differentially expressed genes (DEGs) (—logFC— > 1, p-value < 0.05) were visualized by heatmaps and volcano plots respectively. Next, the co-expression genes expressed in the three groups of DEGs were obtained by constructing a Venn diagram. In addition, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis were further analyzed the related functions and enrichment pathways of these co-expression genes. Then, qRT-PCR was used to verify the expression levels of co-expression genes in the kidney of DKD and control mice. Finally, protein-protein interaction network (PPI), GO, KEGG analysis and Pearson correlation test were performed on the experimentally validated genes, in order to clarify the possible mechanism of them in DKD. Results Our RNA-seq results identified a total of 125 DEGs, including 59 up-regulated and 66 down-regulated DEGs. At the same time, 183 up-regulated and 153 down-regulated DEGs were obtained in GEO database GSE86300, and 76 up-regulated and 117 down-regulated DEGs were obtained in GSE184836. Venn diagram showed that 13 co-expression DEGs among the three groups of DEGs. GO analysis showed that biological processes (BP) were mainly enriched inresponse to stilbenoid, response to fatty acid, response to nutrient, positive regulation of macrophage derived foam cell differentiation, triglyceride metabolic process. KEGG pathway analysis showed that the three major enriched pathways were cholesterol metabolism, drug metabolism–cytochrome P450, PPAR signaling pathway. After qRT-PCR validation, we obtained 11 genes that were significant differentially expressed in the kidney tissues of DKD mice compared with control mice. (The mRNA expression levels of Aacs, Cpe, Cd36, Slc22a7, Slc1a4, Lpl, Cyp7b1, Akr1c14 and Apoh were declined, whereas Abcc4 and Gsta2 were elevated). Conclusion Our study, based on RNA-seq results, GEO databases and qRT-PCR, identified 11 significant dysregulated DEGs, which play an important role in lipid metabolism and the PPAR signaling pathway, which provide novel targets for diagnosis and treatment of DKD.

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Objective To investigate the role of microRNA-155-5p on apoptosis and inflammatory response in human renal glomerular endothelial cells (HRGEC) cultured with high glucose. Methods The primary HRGEC were mainly studied, light microscopy was used to detect changes in cell morphology. Quantitative Real Time-Polymerase Chain Reaction, Western Blot, immunofluorescence were aimed to observe the mRNA and protein expression levels of target gene ETS-1, downstream factors VCAM-1, MCP-1 and cleaved caspase-3 in each group after high glucose treatment as well as transfection with miR-155 mimics or inhibitor. Results The expression of inflammatory factors and apoptosis of HRGEC cells increased under high glucose treatment. Compared with normal-glucose treatment, the expression of microRNA-155 markedly increased in HRGECs treated with high-glucose, as well as the mRNA and protein levels of ETS-1, VCAM-1, MCP-1 and cleaved caspase-3. Overexpression of microRNA-155 remarkably downregulated mRNA and protein levels of ETS-1, VCAM-1, MCP-1 and cleaved caspase-3, whereas miRNA-155 knockdown upregulated their levels. In addition, HRGEC cells were transfected with miR-155 mimics and ETS-1 siRNA with high glucose stimulation. The expression of ETS-1 was positively correlated with the expression of downstream factors VCAM-1 and MCP-1. These results suggest that ETS-1 can mediate endothelial cell inflammation by regulating VCAM-1 and MCP-1. Conclusion MiR-155 can negatively regulate the expression of target gene ETS-1 and its downstream factors VCAM-1, MCP-1 and cleaved caspase-3, thus mediating the inflammatory response and apoptosis of HRGEC.

Background: Chronic kidney disease (CKD) is a serious threat to human health worldwide, and its incidence is increasing annually. The incidence of CKD is a worldwide problem that heavily threatens human health and is increasing annually. A growing amount of information is emerging about the role of miRNAs in the regulation of renal fibrosis, which has aroused interest in the development of drugs that block pathogenic miRNAs or restore protective miRNAs levels. Methods: The aim of this study was to identify the microRNAs (miRNAs) differentially expressed in renal tissues from patients with progressive DN and FSGS of high fibrosis scores to investigate the function and mechanism of miRNAs in renal fibrosis by using kidney tissues from normal and MCD patients as controls. First, we investigated the expression profiles of miRNAs in human kidney biopsy samples using microarray. Then, two new miRNAs were selected to explore the biological functions in TGF-β1 or HG -induced cell models using human proximal renal tubule cells (HK-2). GO and KEGG Pathway Enrichment Analysis were used to explore the target genes and their mechanism in renal fibrosis. Results: The kidney biopsy samples from three types of diseases representing different fibrosis states, two novel miRNAs, hsa-miR-1470-3p and hsa-miR-4483-3p, were detected as consistently differentially expressed among all three types of patient's renal samples and in mice model. In vitro, hsa-miR-4483-3p was suppressed, whereas hsa-miR-1470-3p was induced by treatment with TGF-β1 or HG. Inhibition of hsa-miR-1470-3p or overexpression of hsa-miR-4483-3p promoted HG or TGF-β1-induced fibrosis in HK-2 cells. The further study revealed that MMP-13 and TIMP1 were the target genes of hsa-miR-1470-3p and hsa-miR-4483-3p, respectively. Conclusion: In conclusion, the present study identifies newly dysregulated miRNA profiles related to fibrosis kidneys. Hsa-miR-1470-3p and hsa-miR-4483-3p are demonstrated to involve in kidney fibrosis by regulation of MMP13, TIMP1 respectively. Our results may represent a promising research direction for renal disorders and help identify new biomarkers and therapeutic targets for chronic kidney disease.