GCG and type 2 diabetes mellitus: In addition, GLP-1 inhibits glucagon secretion, slows gastric emptying, regulates appetite and food intake, stimulates β-cell neogenesis and proliferation, and promotes β-cell survival both in vitro and in vivo [12], and deficient incretin signalling has been suggested to be a major reason of insufficient insulin release and excessive glucagon release in type-2 diabetics [13].