Rosmarinic acid ameliorates diabetic nephropathy in uninephrectomized diabetic rats

ABSTRACT

Oxidative stress plays an important role in diabetic nephropathy pathogenesis. Rosmarinic acid, a plant phenolic compound, was first used as an antioxidant agent for inhibition of diabetic nephropathy. Forty male rats were uninephrectomized from the left flank. The rats were divided in four groups randomly; group one as control, group two diabetic untreatment, groups three and four treatment with rosmarinic acid by 100 or 200 mg/kg/d orally respectively. Diabetes was induced in the second, third and fourth groups by alloxan injection subcutaneously. After 8 weeks treatment, serum malondialdehyde was measured by thiobarbituric acid [TEA] test. Serum creatinine and serum urea were measured by kits. Kidney paraffin sections were prepared and stained by periodic acid Schiff method,Glomerular volume and glomerular number were estimated by stereological rules and glomerular sclerosis was studied semi-quantitatively. Data were analyzed by non-parametric Man Whitney test [using SPSS 13 software] and P< 0.05 was considered significant. Rosmarinic acid [100 or 200 mg/kg] significantly inhibited glomerular hypertrophy, glomerular number loss, glomerulosclerosis, lipid peroxidation, serum urea and creatinine compared with the diabetic untreated group. The level of glomerular number and serum malondialdehyde in the treated groups [100 mg/kg or 200 mg/kg of rosmarinic acid] was maintained at the same level as compared to the control group. Rosmarinic acid could significantly reduce glomerular hypertrophy, loss of glomerular number, glomerulosclerosis and attenuated serum urea and serum creatinine in diabetic rats