Effects of the Crude Aqueous Extract and Isolated Fractions of Morinnga Stenpetalla in Leaves in Normal and Diabetic Mice

Abstract

The leaves of Moringa stenopetalla are traditionally employed for the treatment of diabetes mellitus in Ethiopia. The aim of this study was to evaluate the effect of the aqueous extract and isolated fractions of these plant materials on blood glucose levels in normal and diabetic mice. Non-diabetic and diabetic mice received 500mg/kg of the crude extract or chloroform fraction or n-butanol fraction or aqueous residue fraction or 0.66mg/kg glibenclamide (standard antidiabetic drug) or 10ml/kg distilled water (served as negative control). Diabetes was induced with alloxan. The blood glucose concentration was determined from the tail vein of each animal every 1.5 hours for 6 hours. The oral LD50 of the crude extract was also determined. In the non-diabetic mice, the crude aqueous extract showed significant reduction (p<0.05) in blood glucose level 6 hours after its administration; while the chloroform and n-butanol fractions showed significant reduction (p<0.05) 3 hours and 4.5 hours after their administration, respectively. The aqueous residue fraction did not significantly change the blood glucose level at any of the observation period. In alloxan induced diabetic mice, the crude aqueous extract reduced the blood glucose level significantly (p<0.05) at all periods of observation except at 6 hours after its administration; while the chloroform fraction reduced it throughout the observation period. For both n-butanol and aqueous residue fractions a significant reduction (p<0.005) in the blood glucose levels was observed at 1.5 hours of their administration. The present data showed that the crude extracts as well as the n-butanol and chloroform fractions of the leaves of M. stenopetalla have both hypoglycemic and antihyperglycemic effects, the later effect being more pronounced supporting the claim of the traditional use of the plant in diabetes mellitus.