Alcoholic leaf extract of Plectranthus amboinicus regulates carbohydrate metabolism in alloxan-induced diabetic rats.

OBJECTIVE

The present investigation was undertaken to explore the possible mechanisms of Plectranthus amboinicus leaf extract in alloxan-induced diabetic rats.

METHODS

Control and alloxan-induced diabetic albino rats received different treatments; orally control (vehicle), 200 mg/kg and 400 mg/kg of ethanol extract of Plectranthus amboinicus (PAEE) and 600 μg/kg of glibenclamide (standard) for 15 days. At the end of the experiment, the animals were sacrificed and enzyme activities of carbohydrate metabolism were measured in the liver.

RESULTS

Diabetic control rats showed a significant elevation (P < 0.001) in fasting blood glucose on successive days of the experiment as compared with their basal values, which was maintained over a period of 2 weeks. Daily oral treatment with PAEE showed a significant reduction (P < 0.001) in the blood glucose levels on successive days of the experiment as compared with their basal values. The most pronounced antihyperglycemic effect was obtained with the dose of 400 mg/kg. PAEE shows a dose-dependent reduction in gluconeogenic enzymes like glucose-6-phosphatase and fructose-1,6-disphosphatase. After 15 days of treatment with PAEE, glycolytic enzymes like phosphoglucoisomerase resulted in a significant increase with a concomitant significant decrease in the activities of aldolase. On the other hand, glucose-6-phosphate dehydrogenase was significantly improved in diabetic rats on administration of PAEE; the 400 mg/kg dose of PAEE elicited a more potent effect compared with the 200 mg/kg dose.

CONCLUSIONS

The results obtained in this study provide evidence of the antidiabetic activity of PAEE, mediated through the regulation of carbohydrate metabolic enzyme activities.