Minireview: update on incretin biology: focus on glucagon-like peptide-1.

The incretin hormone, glucagon-like peptide-1 (GLP-1), is now being used in the clinic to enhance insulin secretion and reduce body weight in patients with type 2 diabetes. Although much is already known about the biology of GLP-1, much remains to be understood. Hence, this review will consider recent findings related to the potential for enhancing endogenous levels of GLP-1 through selective use of secretagogues and the beneficial cardiovascular, neuroprotective, and immunomodulatory effects of GLP-1, as well as the possible effects of GLP-1 to enhance beta-cell growth and/or to induce pancreatitis or thyroid cancer. Finally, the potential for molecular medicine to enhance the success of GLP-1 therapy in the clinic is considered. A better understanding of the fundamental biology of GLP-1 may lead to new therapeutic modalities for the clinical use of this intestinal hormone.