Drug repurposing for type 2 diabetes: computational studies of potential alpha-glucosidase inhibitors from DrugBank

Type 2 diabetes is a prevalent disease that continues to pose a significant health burden worldwide. Despite the availability of various drugs for its management, the number of diagnoses and mortalities is persistently on the rise. Alpha-glucosidase inhibition has emerged as a promising therapeutic strategy to prevent postprandial hyperglycaemia. One approach in drug discovery is drug repurposing, which involves investigating existing drugs for new therapeutic indications. This study used a three-stage molecular docking approaches to screen the DrugBank database for potential alpha-glucosidase inhibitors against N-terminal maltase glucoamylase (ntMGAM) target. We selected 10 compounds with top docking performance, and rescoring these compounds with MMGBSA calculations produced arbekacin, neamine, and sisomicin with a binding free energy of - 72.13, - 55.14, and - 69.07 kcal/mol, respectively, as the top three compounds. These compounds were subsequently analysed and compared with the standard drug, acarbose for their protein-binding stability using molecular dynamics simulation (MDS) approach. The MDS analysis suggests that sisomicin exhibited the most stable interactions and stronger post-MDS binding free energy with alpha-glucosidase. These findings suggest that sisomicin is a potential inhibitor of alpha-glucosidase, and a novel candidate for drug repurposing in antidiabetic therapy.