Hua Lin

Background: Increasing evidence suggests that immune cell infiltration contributes to the pathogenesis and progression of diabetic nephropathy (DN). We aim to unveil the immune infiltration pattern in the glomerulus of DN and provide potential targets for immunotherapy.Methods: Infiltrating percentage of 22 types of immune cell in the glomerulus tissues were estimated by the CIBERSORT algorithm based on three transcriptome datasets mined from the GEO database. Differentially expressed genes (DEGs) were identified by the “limma” package. Then immune-related DEGs were identified by intersecting DEGs with immune-related genes (downloaded from Immport database). The protein–protein interactions of Immune-related DEGs were explored using the STRING database and visualized by Cytoscape. The enrichment analyses for KEGG pathways and GO terms were carried out by the gene set enrichment analysis (GSEA) method.Results: 11 types of immune cell were revealed to be significantly altered in the glomerulus tissues of DN (Up: B cells memory, T cells gamma delta, NK cells activated, Macrophages.M1, Macrophages M2, Dendritic cells resting, Mast cells resting; Down: B cells naive, NK cells resting, Mast cells activated, Neutrophils). Several pathways related to immune, autophagy and metabolic process were significantly activated. Moreover, 6 hub genes with a medium to strong correlation with renal function (eGFR) were identified (SERPINA3, LTF, C3, PTGDS, EGF and ALB).Conclusion: In the glomerulus of DN, the immune infiltration pattern changed significantly. A complicated and tightly regulated network of immune cells exists in the pathological of DN. The hub genes identified here will facilitate the development of immunotherapy.

BackgroundIncreasing evidence suggests that immune cell infiltration contributes to the pathogenesis and progression of diabetic nephropathy (DN). We aim to unveil the immune infiltration pattern in the glomerulus of DN and provide potential targets for immunotherapy. MethodsInfiltrating percentage of 22 types of immune cell in the glomerulus tissues were estimated by the CIBERSORT algorithm based on three transcriptome datasets mined from the GEO database. Differentially expressed genes (DEGs) were identified by the “limma” package. Then immune-related DEGs were identified by intersecting DEGs with immune-related genes (downloaded from Immport database). The protein-protein interactions of Immune-related DEGs were explored using the STRING database and visualized by Cytoscape. The enrichment analyses for KEGG pathways and GO terms were carried out by the gene set enrichment analysis (GSEA) method. Results9 types of immune cell were revealed to be significantly altered in the glomerulus tissues of DN (Up: B cells memory, T cells CD4 naive, Macrophages M2, Dendritic cells resting, Mast cells resting, Mast cells activated; Down: NK cells resting, Monocytes, Neutrophils). Correlation analysis revealed that immune infiltration act as a complicated and tightly regulated network, among which T cells gamma delta and T cells CD4 naive show the most synergistic effect (r = 0.58, p ＜ 0.001); meanwhile, T cells CD8 and T cells CD4 memory resting show the most competitive effect (r = - 0.67, p ＜ 0.001). Several pathways related to immune were significantly activated. Moreover, 6 hub genes with a medium to strong correlation with renal function (eGFR) were identified (ALB, EGF, FOS, CXCR1, CXCR2, CCL2). ConclusionIn the glomerulus of DN, the immune infiltration pattern changed significantly. A complicated and tightly regulated network of immune cells exists in the pathological of DN. The hub genes identified here will facilitate the development of immunotherapy.

The present study was designed to investigate the protective effects of Cordyceps militaris polysaccharides (CMP) on STZ-treated DN mice. CMP were identified by FT-IR and HPLC. Diabetic nephropathy (DN) was induced in male C57BL/6 mice by the injection of streptozotocin (STZ, 50 mg kg⁻¹) in citrate buffer on 5 consecutive days. Administration of CMP at 200 and 400 mg kg⁻¹ or irbesartan at 60 mg kg⁻¹ in the STZ-treated mice could prevent the damage caused by STZ. CMP significantly reduced the STZ-induced higher expression of the kidney index, TC, TG, MDA, urinary protein, Scr, and BUN, while it markedly increased the STZ-induced decrease in GSH levels compared with the DN group. Histopathology analysis of the kidney by PAS, Masson, and HE staining confirmed the renal injury induced by STZ and the protective effects of CMP. Transmission electron microscopy (TEM) results confirmed the severe foot process effacement induced by STZ, but CMP treatment inhibited the podocytes’ structure defects and ameliorated the function of podocytes. Desmin was measured by immunofluorescence and was related to podocyte injury. The results showed that CMP lessened the expression of desmin induced by STZ. CD68 expression was measured by immunohistochemistry analysis, and the expressions of IL-1β, IL-6, and MCP-1 mRNA were measured by qRT-PCR. The results showed that CMP suppressed the expressions of CD68, IL-1β, IL-6, and MCP-1 mRNA induced by STZ. The role of autophagy in the treatment of DN mice with CMP was detected by TEM and western blotting. The results showed that the administration of CMP was able to overcome the STZ-treated autophagy deficiency, significantly increase the rate of autophagy in the kidney, promote the expression of Atg5, beclin1 and LC3 protein, and reduce the expression of p62 protein. In conclusion, the present study demonstrates that CMP exert a protective effect on DN in STZ-treated mice possibly via activation of autophagy.