Bioactive compounds in methanol extract of Newbouldia laevis leaf inhibit alpha-glucosidase and enhance antioxidant status in fructose/alloxan-induced type 2 diabetic rats.

Abstract

Newbouldia laevis (NL) has been folklorically known to be used for managing diabetes mellitus. Its mechanism of action against this disease has not been fully proven. The study was therefore designed to investigate the effect of NL bioactive compounds on diabetic parameters in vivo and in silico. For in vivo study, twenty-five rats divided into five groups (n = 5) were given 20% fructose solution for two weeks and grouped as follows: normal control (NC) received 10ml/kg olive oil; diabetes was induced in groups 2 (Diabetic control- DC), 3, 4 and 5 using 80mg/kg alloxan, and they were administered 10ml/kg olive oil, 250mg/kg, 500mg/kg MENL, and 5mg/kg glibenclamide, respectively. Methanol extract of NL (MENL) was characterized using Gas Chromatography Mass Spectrometry (GC-MS). Molecular docking was done on bioactive compounds obtained from GC-MS analysis against α-glucosidase to unravel probable mechanism of action of the extract. Serum insulin and antioxidant were determined using ELISA and spectroscopy techniques respectively. As against DC, blood glucose level was significantly low while insulin was high in MENL treated groups. Antioxidant increased significantly in MENL treated groups compared to DC. Four hit molecules inhibited α-glucosidase more than acarbose. It could be inferred that bioactive compounds in NL may exhibit their normoglycemic effect by inhibiting α-glucosidase, improving insulin sensitivity and enhancing antioxidant status.