GLP1R and type 2 diabetes mellitus: The pharmacological management of T2DM has recently been expanded to several different classes of drugs (dipeptidyl peptidase-4 (DPP4) inhibitors, sodium-glucose cotransporter 2 (SGLT2) inhibitors, glucagon-like peptide-1 receptor agonists (GLP1-RA), etc.)in addition to metformin, sulfonilureas and alpha-glucosidase inhibitors [33].