Dendropanax morbifera Protects against Renal Fibrosis in Streptozotocin-Induced Diabetic Rats

The aquatic extract of Dendropanax morbifera (DP) is typically consumed as a beverage in Korea and China and is also used in various traditional medicines. However, the functional role of DP on diabetes-induced renal fibrosis is unclear. Here, the protective effects of DP extract against diabetes-induced renal fibrosis were evaluated. Streptozotocin (STZ, 60 mg/kg) was injected intraperitoneally in rats to induce diabetes. After 5 days, DP extract (25 mg/kg/day) and metformin (50 mg/kg/day) were administered orally to diabetic rats for 28 days. DP administration protected both body and organ weight loss in STZ-treated diabetic rats. Significant improvements in serum blood urea nitrogen (BUN), creatinine, and oxidative stress parameters were observed in diabetic rats by DP administration. DP extract markedly protected diabetic-induced histopathological damages in the kidney and pancreas. A significant reduction was observed in microalbumin, kidney injury molecule-1 (KIM-1), selenium binding protein-1 (SBP1), and pyruvate kinase muscle isozyme M2 (PKM2) levels in the urinary excretion of diabetic rats after the administration of DP extract. The expression of pro-inflammatory cytokines and fibrosis marker levels were significantly reduced in the kidney of diabetic rats. Our results strongly indicate that DP extract exhibits protective activity against diabetes-induced renal fibrosis through ameliorating oxidative stress and inflammation. Therefore, we suggest that DP extract can be used as a preventive agent on the progression of diabetic nephropathy and renal fibrosis.