HYPOGLYCEMIC AND HYPOLIPIDEMIC ACTIVITIES OF HALLEA STIPULOSA STEM BARK AQUEOUS EXTRACT ON DEXAMETHASONE INDUCED INSULIN RESISTANCE IN RATS.

Poualeu Kamani S. L.*, Wansi S. L., Miaffo D., Tchoumba T. L., Nkeng-Efouet A. P., Kamanyi A.

ABSTRACT

The aim of this study was to examine the hypoglycemic and hypolipidemic activities of aqueous extract of Hallea stipulosa on dexamethasone induced insulin resistance in rats, and to evaluate in vitro the inhibitory activity of this plant extract on α- glucosidase enzyme. Insulin resistance was induced by subcutaneous injection of dexamethasone (1 mg/kg) for 10 days, one hour before administration of different treatments. Body weight and blood glucose level were measured on day 1, 5 and 10. At the end of treatment, glucose tolerance test was performed to the rats, blood samples were collected for triglyceride, total cholesterol, LDL-c and HDL-c level determination. Organs (heart, liver pancreas and kidney) were also collected for relative organ weight determination. The results showed a significant increase (p < 0.001) in serum triglyceride, total cholesterol, LDL-c, blood glucose level, liver weight and a significant decrease (p < 0.001) in HDL-c and body weight observed in dexamethasone control group compared to normal control group. Hallea stipulosa at doses 25, 50 and 100 mg/kg significantly reversed the alteration induced by dexamethasone. Hallea stipulosa significantly reduced postprandial glucose and showed appreciable α-glucosidase inhibitory effect in a concentration-dependant manner (IC50=13.14). These results suggest that Hallea stipulosa stem bark aqueous extract may be useful for the treatment of type 2 diabetes mellitus.

Keywords: Hallea stipulosa, dexamethasone, ?-glucosidase, rats.