Background: The prevention against diabetic nephropathy is still required due to the limitation of the current therapeutic strategy. Based on the effect of antioxidants on the restoration of renal dysfunction in diabetic nephropathy, we hypothesized that the combination extract of seed of Mangifera indica or mango var. Namdokmai and aerial part of Polygonum odoratum or Vietnamese coriander (MPO) which possessed antioxidant activity might prevent diabetic nephropathy and be safe for consumption.
Objective: To test this hypothesis, we aimed to determined acute toxicity and renoprotective effect of MPO in STZ-diabetic rats.
Materials and Methods: Acute toxicity was assessed in Wistar rats. Single administration of MPO at dose of 5,000 mg.kg-1 BW failed to produce mortality and related toxicity signs. To test renoprotective effect, diabetic rats were induced by a single injection of streptozotocin (STZ). STZ-diabetic rats were orally given MPO at doses of 2, 10 and 50 mg.kg-1 BW for 10 weeks. Then, they were determined body weight, kidney weight, urine volume, urine specific gravity and blood biochemical parameters at the end of experiment. In addition, kidneys were collected and determined histomorphology, nitric oxide synthase (NO), NF-kappa B (NF-kB), vascular endothelial growth factor (VEGF), aldose reductase (AR) and oxidative stress status.
Results: Low dose of MPO significantly improved creatinine clearance while medium and high doses of MPO significantly improved albuminuria. MPO also improved Bowman space, glomerular tuft, eNOS, oxidative stress status and NF-kB but no significant change of VEGF and AR were observed in kidney. Therefore, the possible underlying mechanism of MPO might be partly associated with the improvement of kidney structures, oxidative stress status, eNOS and NF-kB in kidney.
Conclusion: Our data suggest that MPO is the potential candidate of renoprotectant against diabetic nephropathy but sub chronic toxicity and clinical trial are still essential.

Keywords: Acute toxicity, Diabetic nephropathy, Renoprotective, Mangifera indica, Polygonum odoratum