Astragaloside suppresses apoptosis of the podocytes in rats with diabetic nephropathy via miR-378/TRAF5 signaling pathway

Apoptosis of podocytes plays a crucial role in diabetic nephropathy (DN) development, and astragaloside (AS-IV) has a significant impact on podocyte apoptosis. This study aims to explore the effect of AS-IV on diabetic nephropathy progression. The diabetic nephropathy model was established in rats with streptozotocin (STZ) injection. The albuminuria was examined by using the enzyme linked immunosorbent assay (ELISA). The expression of miR-378, tumor-necrosis factor (TNF) receptor (TNFR)-associated factor 5 (TRAF5) mRNA and protein was analyzed by qRT-PCR and western blot, respectively. Cell transfection was conducted for modulating endogenous expression of miR-378. Dual luciferase reporter assay was used to evaluate the interaction between miR-378 and TRAF5. The terminal deoxynucleotidy transferase dUTP nick end labeling (TUNEL) staining assay was performed for apoptosis detection. AS-IV protected diabetic rats from developing into diabetic nephropathy. The expression of miR-378 was down-regulated in diabetic nephropathy rats, which was reversed by AS-IV. AS-IV enhanced the expression of miR-378 in podocytes treated with high glucose. MiR-378 negatively regulated TRAF5. AS-IV inhibited the expression of TRAF5 through miR-378. AS-IV suppressed apoptosis of podocytes via targeting miR-378. AS-IV suppresses apoptosis of the podocytes through the miR-378/TRAF5 signaling pathway, and thereby repressing diabetic nephropathy development.