Antidiabetic Property of a Fraction of the Methanol Extract of the Seeds of Abrus precatorius in Alloxan-induced Diabetic Rats

Abstract

Introduction: Diabetes mellitus (DM) is a group of metabolic diseases characterized by hyperglycemia resulting from defects of insulin secretion and/or increased cellular resistance to insulin. Abrusprecatoriushas been used for the treatment of various ailments including diabetes mellitus. This study is aimed at evaluating the possible anti-diabetic effect of the methanol fraction 2 (F2) of the seeds of Abrusprecatoriusin alloxan-induced diabetic Wistar albino rats. Methods: The methanol extract of the seeds of A. precatorius Linn Fabaceae was fractionated by Sephadex G15. Diabetes was induced by a single intraperitoneal administration of 150 mg/kg bodyweight of alloxan. Acute toxicity (LD50) study was done using Lorke’s method. The antidiabetic activities of Fraction 2 (F2) and the biochemical parameters were investigated using standard diagnostic methods. Results: The value of the LD50 is 529.2 mg/kg bw. Oral doses (5, 10 and 20 mg/kg bw.) of the extract caused a dose-dependent significant (p<0.05) reductions in blood glucose concentrations compared with diabetic untreated controls. There were significant decreases (p<0.05) in the total cholesterol and triacylglycerol levels of rats in the treatment groups compared with the diabetic untreated group. The groups that were treated with glibenclamide, 5 mg/kg of the fraction, 20mg/kg of the fraction and the group that was pre-treated with 10mg/kg of the fraction before the induction of diabetes showed a significant decrease (p<0.05) in the concentration of low-density lipoprotein and significant increase (p<0.05) in high-density lipoprotein concentrations compared with the diabetic untreated group. The protein level increased non-significantly (p>0.05) in all the test groups compared with the diabetic untreated control group except the pre-treated group which increased significantly (p<0.05). Conclusion: The results obtained from this study revealed that the methanol fraction of A. precatorius has antidiabetic property which can be as a result of the important phytochemicals found in the F2 fraction. Fraction 2 (F2) however showed improvement in lipid profile.