GLP1R and type 2 diabetes mellitus: Glucagon-like peptide-1 receptor (GLP-1R) agonists are promising agents for treating type 2 diabetes mellitus, since they augment glucose-dependent insulin secretion with minimized low risk of hypoglycaemia (Hansen et al., 2009; Lin and Wang, 2009; Cohen et al., 2013; Meloni et al., 2013).