Effects of Fermented Soya Bean Supplements on Serum Insulin and Leptin Levels of High Fat Diet-induced Type 2 Diabetes Mellitus in Rabbits

Abstract

Background: Increase in body fat and obesity are the main risk factors for type 2 diabetes mellitus which leads to several complications that affect many organs of the body when poorly controlled. Plant food sources rich in fibre and antioxidants play an important role in the management of diabetes mellitus. This study aimed to evaluate the effects of fermented soya bean supplements on serum insulin and leptin levels of high fat diet-induced type 2 diabetes mellitus in rabbits. Methods: Twenty rabbits of both sexes weighing, 1–2kg were used. Type 2 diabetes was induced by feeding the animals with a high fat diet for eight weeks. Blood glucose levels were determined after the induction period and rabbits having 130 mg/dL and above were selected for the study. The animals were grouped into four groups with five (n=5) rabbits in each group: Group 1 (diabetic control), received distilled water ad libitum for six weeks; Groups 2, 3 and 4 (diabetic rabbits) were fed with 12.5%, 25% and 50% fermented soya bean supplements respectively for a period of six weeks. Fasting blood glucose levels were determined at weekly interval during the treatment period. At the end of the experiment, the rabbits were euthanized by cervical dislocation and blood samples were collected for the determination of insulin, and leptin levels. Data obtained were analysed using ANOVA. Results: The result showed a significant decrease (P≤0.05) in leptin levels (ng/mL) in groups 2, 3 and 4 (11.30 ± 0.20, 9.20 ± 2.06 and 6.40 ± 1.36, respectively) as compared with the control (18.8 ± 1.59). Insulin levels were also decreased in all the treated groups when compared with the control, though not statistically significant, it may be biologically significant. Conclusion: The results of the study show that fermented soya bean supplementation possesses anti-diabetic properties and may help in the control of hyperleptinaemia