Improvement of glucose tolerance in rats fed with diets containing Vernonia amygdalina leaves

Abstract

The effect of 5% and 10% dietary incorporation of leaves of Vernonia amygdalina (VA) on oral glucose tolerance was studied in normoglycemic male albino rats. The feeding of the vegetable incorporated diets (5% VA and 10%VA) resulted in marked improvement in oral glucose tolerance in rats. After one week of diet administration, following an oral glucose load (3g/kg body weight), blood glucose concentration (BGC) (mg/dL) in rats fed the 5% VA peaked at 15minutes (147.24± 18.46), while the BGC in rats fed the control diet and 10% VA peaked at 30mins (180.00 ± 28.57 and 159.48 ± 16.07 respectively). After two weeks of feeding of the vegetable incorporated diets, post administration BGC peaked at 15 minutes in the test groups [5% VA diet (152.64± 33.46) and 10% VA diet group (121.95± 24.78)] while the peak remained at 30 minutes in the control group. After 3 weeks of diet administration BGC remained peaked at 15 minutes in the 5% and 10% VA diet groups (137.16 ± 61.29 and 132.75 ± 8.86 respectively). Rats in both test groups, after 3 weeks on the test diets, had their glycaemic indices reduced by 15- 18%. These findings indicate that feeding on diets containing Vernonia amygdalina could positively modulate oral glucose tolerance. The vegetable could be useful in dietary management of conditions associated with oral glucose tolerance, and by extension, hyperglycemia.

Keyword: Diabetes mellitus; Dietary incorporation; Oral glucose tolerance; Vernonia amygdalina