ABSTRACT
BACKGROUND: The aims of the present study were to assess whether the antidiabetic activity of mature coconut water (MCW) is mediated through L-arginine-nitric oxide pathway in diabetic rats, and to study the effects of MCW on blood coagulation. METHODS: Diabetes was induced in male Sprague-Dawley rats by injecting them with alloxan (150 mg/kg body weight). MCW (4 mL/100 g body weight) and L-arginine (7.5 mg/100 g body weight) was given orally for 45 days. L-NAME was given at a dose of 0.5 mg/kg body weight. Concentrations of blood glucose, plasma insulin, glycosylated hemoglobin (HbA1c), L-arginine, urine volume and urinary creatinine levels, activity of nitric oxide synthase (NOS), and arginase as well as the abnormalities in hemostasis and thrombosis were measured in all the experimental groups. RESULTS: Treatment with MCW and L-arginine reduced the concentration of blood glucose and HbA1c in diabetic rats. MCW and L-arginine treatment exhibited significant antithrombotic activity in diabetic rats, which was evident from the reduced levels of WBC, platelets, fibrin, and fibrinogen. MCW and L-arginine treatment prolonged the prothrombin time in diabetic rats and reduced the activity of Factor V. In addition to this, the activity of nitric oxide synthase, liver and plasma arginine content, and urinary nitrite were higher in MCW-treated diabetic rats whereas L-NAME treatment inhibited the beneficial effects induced by MCW and arginine. CONCLUSIONS: The results clearly indicate that L-arginine is a major factor responsible for the antidiabetic and antithrombotic potential of coconut water, and is mediated through the L-arginine-nitric oxide pathway.
