HYPOGLYCEMIC ACTIVITY OF COCCINIA-INDICA AND MOMORDICA-CHARANTIA IN DIABETIC RATS - DEPRESSION OF THE HEPATIC GLUCONEOGENIC ENZYMES GLUCOSE-6-PHOSPHATASE AND FRUCTOSE-1,6-BISPHOSPHATASE AND ELEVATION OF BOTH LIVER AND RED-CELL SHUNT ENZYME GLUCOSE-6-PHOSPHATE-DEHYDROGENASE

Coccinia indica leaves were extracted with 60 % ethanol, solvents were evaporated and the residue was suspended in water. This suspension wa s administered orally at a dose of 200 mg/kg body wt. after 18 h of fa sting to normal fed and streptozotocin-induced male diabetic rats (180 -250 g). After 90 min the rats were killed, and blood-glucose, hepatic glucose-6-phosphatase, fructose-1,6-bisphosphatase and glucose-6-phos phate dehydrogenase (G6PDH) and red-cell G6PDH were assayed. Blood sug ar was depressed by 23 % (P < 0.01) and 270 (P < 0.001) in the normal fed and streptozotocin-diabetic rats respectively compared with contro ls which were given distilled water. Hepatic glucose-6-phosphatase and fructose-1,6-bisphosphatase activities were depressed by 32 00 (P < 0 .001) 30 % (P < 0.05) respectively in the streptozotocin-diabetic rats , compared with 19 % (P < 0.02) and 20 % (P < 0.01) depression in the normal fed controls, whereas both the red-cell and hepatic G6PDH activ ities were found to be elevated by feeding the extract in the streptoz otocin-diabetic and in the normal fed controls. Similar results were o btained with the 95 %-ethanolic extract of Momordica charantia. Taken together, these results indicate that Coccinia indica and Momordica ch arantia extracts lowered blood glucose by depressing its synthesis, on the one hand through depression of the key gluconeogenic enzymes gluc ose-6-phosphatase and fructose-1,6-bisphosphatase and on the other by enhancing glucose oxidation by the shunt pathway through activation of its principal enzyme G6PDH.