Synthesis of a 1,2,3-bistriazole derivative of embelin and evaluation of its effect on high-fat diet fed-streptozotocin-induced type 2 diabetes in rats and molecular docking studies.

The embelin derivative 2a was synthesized with the 1,2,3-bistriazole and spectral data confirmed its structural identity. Anti-diabetic and anti-lipidemic effects were evaluated using HFD-STZ induced type 2 diabetic rats. The derivative 2a (30 mg/kg b wt.) supplementation significantly (P ≤ 0.01) normalized the changed biochemical parameters like fasting blood glucose (FBG), body weights, plasma insulin level, total cholesterol (TC), triglycerides (TG) and marker enzymes of carbohydrate metabolism. The derivative 2a (30 mg/kg) also showed a significant effect on oral glucose tolerance test (OGTT) and intraperitoneal insulin tolerance test (ITT). But 15 mg/kg dose of derivative 2a failed to show any significant effects in HFD-STZ induced type2 diabetic rats. Histopathology analysis substantiated the protective effect of this derivative 2a (30 mg/kg b wt.) on the β-cells of the pancreatic, liver and adipose tissues in diabetic treated rats. Further, the expressions of PPARγ and GLUT4 were significantly enhanced in the epididymal adipose tissue. The HOMO and LUMO energies characterized the molecular stability of the derivative 2a with 6-311G++ (d, p) in DFT/B3LYP/LanL2DZ method using Gaussian09 program package. The molecular docking analysis also confirmed the activity of derivative 2a through hydrogen bond interaction with ARG 288, GLU 343, SER 342 and least energy value (-7.72 kcal/mol). Hence, the embelin-1,2,3-bis triazole derivative 2a (30 mg/kg) enhanced the activity of embelin and might be acting as a suitable drug for type 2 diabetes, obesity and its complications.