Nephroprotective effects of Aralia taibaiensis in a high-fat diet-streptozotocin rat model of diabetic nephropathy

Diabetic nephropathy (DN) has emerged as the foremost cause of end-stage renal disease (ESRD) globally. Endoplasmic reticulum (ER) stress plays a critical role in DN progression. Triterpenoid saponin from Aralia taibaiensis (sAT) has been reported to possess anti-diabetic and anti-oxidant effects. The aim of this study was to examine the influence of sAT on DN treatment and elucidate potential underlying mechanisms. A high-fat diet (HFD) and Streptozotocin (STZ) were employed to induce DN in male Sprague Dawley (SD) rats which were subsequently treated with varying concentrations of sAT for 8 weeks. Our findings reveal that different doses of sAT significantly mitigated hyperglycemia, reduced urinary albumin excretion, and decreased plasma creatinine and blood urea nitrogen levels in DN rats. Moreover, sAT administration improved body weight, alleviated renal fibrosis and histopathological changes in the diabetic kidneys. Notably, sAT treatment partially restored increased Bax expression and decreased Bcl-2 expression. Additionally, sAT inhibited ER stress-related proteins, including GRP78, p-PERK, ATF4 and CHOP in kidneys of DN rats. These results suggest that sAT ameliorated experimental diabetic nephropathy, at least in part, through ER stress pathway. These findings provide a scientific basis for the potential development of sAT as a therapeutic agent for DN treatment.