Molecular Interactions and Docking Studies of the Phytochemical Constituents of Costus Afer against Therapeutic Targets of Type 2 Diabetes

Diabetes mellitus continues to exist as one of the world’s commonest chronic diseases, and the incidence of diabetes is presumed to grow steadily. With the associated adverse side effects of some of the current drugs, the management of diabetes mellitus continues to pose serious challenge in the medical field. There is a need for more robust approach to the treatment and management of diabetes and plants with their anti-diabetic potentials are expected to play key roles in the discovery of new and more potent pharmaceuticals that can successfully treat diabetes. Costus afer, a reported anti-diabetic plant was investigated in the present study for its anti-diabetic properties against certain therapeutic target of diabetes. Phytochemical constituents of C. afer were obtained through GC-MS analysis. These phytochemicals were docked into the binding pocket of the therapeutic targets (glycogen phosphorylase, pancreatic alpha-amylase, dipeptidyl peptidase IV (DPPIV), aldose reductase). The docking scores from Autodock vina were validated and the correlation coefficient (R2) graph of the docking scores of ChemBL’s 125 compounds, docked into the human aldose reductase binding pocket against their corresponding pIC50 values gives R2=0.86, while the correlation coefficient graph of the docking scores of 50 compounds from ChemBL, docked into Dipeptidyl peptidase IV binding pocket against their corresponding pIC50 values gives R2=0.92. In the present study, the phytochemical Citronellyl isobutyrate with a binding affinity of -9.1 kcal/mol has the best inhibitory effect on the aldose reductase receptor/enzyme. The drug likeness of Citronellyl isobutyrate being the lead compound was determined through the calculation of its molecular properties. Citronellyl isobutyrate is a promising therapeutic agent in the treatment of type II diabetes and its associated complications.