GCG and type 2 diabetes mellitus: The discovery that glucagon-like peptide-1 (GLP-1) enhances insulin secretion in a glucose-dependent manner and suppresses glucagon release while minimizing the risk of hypoglycemia has led to the development of various structurally distinct GLP-1 receptor (GLP-1R) agonists (GLP-1RAs) with longer circulation times for the management of T2DM [15–17].