Therapeutic potential of glucagon-like peptide 1 in type 2 diabetes.

GLP-1 is a peptide hormone which has been shown to have a variety of antidiabetic actions that could help to reduce glycaemia especially in Type 2 diabetic patients: (1) It produces glucose-dependent stimulation of insulin secretion, and (2) inhibition of glucagon secretion; (3) there is evidence that it increases the rate of (pro)-insulin synthesis and it may also increase insulin sensitivity; (4) it slows the rate of gastric emptying for liquid meals, and possibly also for solid meals; (5) it appears to act within the central nervous system to suppress appetite. These actions of GLP-1 oppose a number of the abnormalities that are commonly observed in patients with Type 2 diabetes. Many facets of Type 2 diabetes, therefore, could be envisaged as a consequence of a lack of GLP-1 effects; they appear to be corrected by the exogenous administration of this gut peptide in short-term experiments. Future activities will aim at the therapeutic exploitation of this pharmacological potential by modifying GLP-1 and its ways of administration to suit the practical needs of patients with Type 2 diabetes.