Comparative study of nephroprotective effects of resveratrol and silymarin in diabetic rats; an experimental histopathologic study

Introduction: Diabetes mellitus (DM) is distinguished as a serious health problem worldwide. The universal outbreak of DM because of urban life and alteration of lifestyle, day to day is increasing. Objectives: The present investigation was designed to evaluate the nephroprotective effects of resveratrol (RSV) and silymarin (SM) on morphologic injury to renal tubular cells in adult male diabetic rats. Materials and Methods: Twenty-five male Wistar rats randomly were designated into five groups (n = 5) including group I (control); rats received normal saline by gavage for 14 days. Group II; rats received a single injection of STZ at a dose of 60 mg/kg intraperitoneally and were also given isotonic saline orally for 14 days. Group III; Rats, after STZ injection, received 100 mg/kg of SM by gavage for 14 days. Group IV; Rats, after STZ injection, received 100 ml/kg of RSV by gavage for 14 days. Group V; rats, after STZ injection, received the combination of SM and RSV at a dose of 100 mg/kg by gavage for 14 days. The kidneys were removed immediately after sacrificing and prepared for morphological examination. Kidney sections were examined for the intensity of kidney damage (vacuolization, flattening, degeneration and necrosis). Results: Significant differences were observed in types of morphologic injury to renal tubular cells (vacuolization, flattening, degeneration and necrosis) between groups (P<0.05). Significantly, both the SM and RSV reduced the injury of renal tubular cells in diabetic rats (P<0.05). Conclusion: The findings of the present study indicated that although the protective effect of SM and RSV was more significant on necrosis and flattening, respectively, SM and RSV produced a nephroprotective impact on the injury of renal tubular cells in diabetic rats than their combination influences.