Biological actions and therapeutic potential of the glucagons-like peptides

cagon-derived peptides cosecreted from gut endocrine cells in response to nutrient ingestion. GLP-1 acts as an incretin to lower blood glucose via stimulation of insulin secretion from islet b cells. GLP-1 also exerts actions independent of insulin secretion, including inhibition of gastric emptying and acid secretion, reduction in food ingestion and glucagon secretion, and stimulation of b-cell proliferation. Administration of GLP-1 lowers blood glucose and reduces food intake in human subjects with type 2 diabetes. GLP-2 promotes nutrient absorption via expan-sion of the mucosal epithelium by stimulation of crypt cell proliferation and inhibition of apoptosis in the small intes-tine. GLP-2 also reduces epithelial permeability, and de-creases meal-stimulated gastric acid secretion and gastro-intestinal motility. Administration of GLP-2 in the setting o