DPP4 and diabetes mellitus: In more recent years, since diabetes is a multifaceted disease, there has been an increase in the development of specific protein-targeted drugs, and specific inhibitors for targets like alpha-glucosidase, dipeptidyl peptidase-4 (DPP4), glucagon-like peptide-1 (GLP-1) receptor, and sodium-glucose co-transporter-2 (SGLT2) have been approved [6].