GLP-1. Generalities and incretin-nutrient interaction

Incretins are hormones produced in the intestine that are released in response to oral intake of nutrients, above all carbohydrates. They are powerful secretors that increase insulin release. The two most important incretin hormones are GIP (glucose-dependent insulinotropic peptide; also known as gastric inhibitory peptide) and GLP-1 (glucagon-like peptide-1). GLP-1 not only stimulates insulin secretion but also reduces glucagon release, slows gastric emptying, improves insulin sensitivity and increases satiety. Other nutrients may also stimulate insulin secretion: oleic acid and serum protein. Currently a new therapeutic armamentarium focused on the role of incretins is being developed to improve the treatment of type 2 diabetes mellitus (DM 2).