Vol. 29, Nš 4

Activity of Raphia hookeri root extract on blood glucose, lipid profile and glycosylated haemoglobin on alloxan induced diabetic rats

G.O. Mbaka; S.O. Ogbonnia; Banjo, A. E.

KEYWORDS: Raphia hookeri, anti-diabetes, beta cells, lipid profile, glycosylated haemoglobin

ABSTRACT: Objective: To evaluate the effect of Raphia hookeri (RH) root extract on blood glucose, glycosylated haemoglobin (HbA1C) and lipid profile on alloxan induced diabetic rats. Methods: Diabetic rats 5 per group received graded doses (50, 100 and 200 mg.kg–1) of the extract or glibenclamide (10 mg.kg–1) or vehicle for 15 days. Blood was collected on days 0, 3, 5, 7, 9, 11, 13, 15 for glucose estimation. Lipid profile was analyzed using modified enzymatic procedure. Insulin assay was by Diagnostic Automation Kit while HbA1C by standard protocol. In oral glucose tolerance test (OGTT), rats received the extract (1 g.kg–1) or glibenclamide (0.01 mg.kg–1) or vehicle and 30 minutes later received oral glucose load (1 g.kg–1). Glucose was estimated at 30 minutes, 1, 2, 3 and 4 hours. The hypoglycaemic activity was assessed on normoglycaemic rat that received extract at 100, 250 and 500 mg.kg–1 and estimated at 0, 4, 8 and 12 hours. Results: Treatment with RH root extract resulted in significant (p < 0.05) dose dependent decrease in fasting blood glucose level from day 3 to the end of experimental period compared to the vehicle group with the extract exhibiting stronger anti-diabetic activity than glibenclamide. RH caused hypoglycaemia after 4 hours with maximum decrease (54.7%) observed after 8 hours. The extract ameliorated dislipidaemia showing more marked activity than glibenclamide. RH extract exhibited insulin stimulatory effect by elevating the plasma insulin level of the diabetic treated animals. It also exerted effective decrease on plasma HbA1C to a level comparable to normal. Conclusion: The RH roots extract attenuated hyperglycaemia by potentiating insulin release. It exhibited effective hypoglycaemic activity and ameliorated dislipidaemia.