The antidiabetic effect of L-carnitine in rats: the role of nitric oxide system

Background: Nowadays, the use of L-carnitine in the treatment of diabetes is increasing. This study was conducted to investigate the effect of co-administration of L-arginine (precursor for the synthesis of nitric oxide) and nitro-L-arginine (nitric oxide synthesis inhibitor) on antidiabetic activity of L-carnitine in diabetic rats. Materials and Methods: In this study, 50 male rats weighing 180-201g were divided into five groups: (1) non diabetic control rats; (2) untreated diabetic rats; (3) diabetic rats treated with L-carnitine 300 mg/kg (4); diabetic rats treated with L-carnitine 300 mg/kg + L-arginine 300 mg/kg; and (5) diabetic rats treated with L-carnitine (300 mg/kg) + nitro-L-arginine (1mg/kg). Type 1 diabetes was induced by a single intraperitoneal injection of 110 mg/kg body weight alloxan. After 30 days, liver malondialdehyde levels, lipid profile, serum glucose, and glycated hemoglobin serum levels were measured. Results: Blood glucose, liver enzymes, glycated hemoglobin, and liver malondialdehyde levels significantly decreased in diabetic rats treated with L-carnitine compared to the untreated diabetic group (P