Effect of Interleukin-17 gene on glomerular ultrastructure and podocyte injury in adriamycin nephropathy rat models.

Abstract

The aim of this study was to investigate the mechanism of interleukin-17 (IL-17) gene in renal tissues of rats suffering from adriamycin (ADM) nephropathy and its effect on the expression level of characteristic proteins, such as Podocalyxin and Nephrin, in podocytes. Sprague-Dawley (SD) rats were randomly divided into a control group (treated with normal saline) and an ADM group (treated with adriamycin). ADM model rats were transfected with lentivirus and divided into a transfection group (transfected with recombinant plasmid IL-17-shRNA) and a negative control group (transfected with plasmid shNC). Coomassie brilliant blue G-250 (CBB) method was adopted to detect the levels of albumin in urine to validate the model. The ultrastructure of rat glomeruli was observed, and the ratio of T helper 17 cells/regulatory T cells (Th17/Treg) was measured by flow cytometry (FCM). The expression levels of IL-17, forkhead box P3 (Foxp3), Nephrin, and Podocalyxin were detected by real-time quantitative PCR (RT-qPCR) and western blot analysis. Results of the study showed that the proteinuria content of the ADM group was significantly higher than that of the control group (P<0.05). In the ADM group, the glomerular basement membrane had uneven thickness and incomplete structure, which showed foot process fusion and electron dense accumulation. However, the glomerular basal membrane in the transfected rats was thin and intact, and a small amount of epithelial foot process fusion and electron density accumulation were observed. The percentages of Th17 cells and IL-17 levels in the ADM group were significantly higher than those in the control group, while the percentages of Treg cells, Foxp3, Nephrin, and Podocalyxin levels were significantly lower than those in the control group (P<0.05). The percentages of Th17 cells, IL-17, Nephrin, and Podocalyxin in the transfection group were significantly higher than those in the ADM group and the negative control group, while the percentages of Treg cells and Foxp3 were significantly lower than those in the ADM group and the negative control group (P<0.05). The results of this study showed that abnormal activation of Th17/IL-17 cells caused podocyte injury and promoted the occurrence and progression of ADM nephropathy. In addition, inhibition of IL-17 gene expression could improve the imbalance of number of Th17 and Treg cells, which may be potentially applied in treatment of patients with primary nephrotic syndrome (PNS).