Abstract:
Nanoencapsulated herbal extracts reveal novel prospects in the development of drug leads against diabetes mellitus. This study attempted to assess the antidiabetic effect of bael fruit aqueous extract encapsulated alginate nanoformulation (BAq-AN) in streptozotocin (STZ)-induced diabetic rats. Bael fruit aqueous extract encapsulated alginate nanoformulation was prepared using the ionic gelation method, mixing alginate to freeze-dried bael fruit extract at 3:1 w/w. Wistar rats (n = 6 per group) were randomly assigned to healthy control (Group 1), STZ-induced control; 60 mg/kg, ip (Group 2), and treatment groups. Group 3 was assigned to metformin at 300 mg/kg. Three groups (4 - 6) were allocated for bael fruit aqueous extract at doses (210, 425: equivalent therapeutic dose, and 850 mg/kg. The last three groups (7 - 9) were assigned to BAq-AN at 155, 310: equivalent therapeutic dose, and 620 mg/kg. Doses in treated groups were calculated based on percentage yield of bael fruit extract and the loading capacity of its nanoformulation. Each treatment was administered orally for 28 days continuously. The serum fasting glucose, insulin level, and glycated hemoglobin (HbA1C) percentage were estimated using standard assay kits. Homeostatic model assessment-β cell function (HOMA-β) and homeostatic model assessment-insulin resistance (HOMA-IR) were calculated. Ethical clearance was granted by ERC, Faculty of Medicine, University of Ruhuna (19.9.2018.3:2). The reduction of HbA1C percentage was more pronounced in the BAq-AN treated groups of rats (310, 620 mg/kg) at 44.8% and 44.5% than their respective crude extracts treated groups of rats (425, 850 mg/kg) respectively. BAq-AN-treated diabetic rats possessed a significant reduction of serum glucose levels at 18.53%, 25.16%, and 8.15% at the doses of 155, 310, and 620 mg/kg, respectively. The mean insulin level and HOMA-β were significantly (p < 0.05) increased, while HOMA-IR values significantly decreased upon the treatment with all three doses of BAq-AN. The insulin level and HOMA-β of the BAq-AN (155 mg/kg) were improved by 3.26% and 36.88% respectively compared to its crude extract-treated rats. BAq-AN exerts antidiabetic activity in STZ-induced diabetic rats and is found to be a promising candidate for development as a nanoencapsulated drug lead against diabetes mellitus.
