The Role of Serum Alpha-Amylase and Glycogen Synthase in the Anti-Diabetic Potential of Terminalia catappa Aqueous Leaf Extract in Diabetic Wistar Rats

Abstract

Background: The endocrinal abnormalities in diabetes mellitus as one of the numerous metabolic disorders is associated with derangement in exocrine functions of the pancreas and ultimately influences blood glucose regulation. Aim: The study was aimed at assessing the role of alpha-amylase and glycogen synthase in anti-diabetic potential of Terminalia catappa in diabetic rats.  Materials and Methods: Thirty five (35) Wistar rats were assigned to 5 groups of 7 animals each. Group 1 served as the control administered distilled water at 5ml/kg bodyweight and group 2 was a non diabetic group given orally, 130/kg body weight of aqueous leaf extract of Terminalia catappa.  Groups 3, 4 and 5 received a single dose of 150mg/kg body weight of alloxan solution intraperitoneally to induce diabetes and rats with blood glucose levels ≥200mg/dl after 72 hours were considered diabetic. This was followed by oral administration of 5ml/kg bodyweight of distilled water, 130mg/kg body weight of Terminalia catappa leaf extract orally and subcutaneous administration of insulin, 0.75U/kg body weight to groups 3 (diabetic), 4(diabetic + extract) and 5 (diabetic + insulin) respectively. Results: The results showed significant (P<.05) increase in serum level of alpha-amylase and glycogen synthase in both non-diabetic extract treated and diabetic groups when compared to control. But these enzymes significantly (P<.05) reduced in diabetic extract and insulin treated groups when compared to the diabetic group.  Conclusion: Therefore the hypoglycaemic potential of Terminalia catappa leaf extract could be attributed to its ability to reduce alpha-amylase level while lowered glycogen synthase might be secondary to reduction in blood glucose.