Incretin-based treatments have emerged as new modalities for the treatment of type 2 diabetes mellitus (T2DM). In contrast to current antidiabetic treatments, these agents target both insulin insufficiency and inappropriate hyperglucagonemia*two major components of type 2 diabetic pathophysiology*both known to contribute significantly to the hyperglycemic state of patients with T2DM. This article outlines the role of hyperglucagonemia in type 2 diabetic pathophysiology, summarizes the physiologic effects of glucagon-like peptide-1 (GLP-1), and gives an introduction to incretin-based treatments with emphasis on their glucagon-lowering effects. Finally, we review available glucagon data from current clinical studies on incretin-based treatment modalities (dipeptidyl peptidase 4 [DPP4] inhibitors and GLP-1 receptor agonists). Most of these studies suggest that both DPP4 inhibitors and GLP-1 receptor agonists lower fasting and postprandial plasma glucagon, and recent data suggest that these effects contribute importantly to the glucose-lowering effect of these treatments.
Journal of Clinical Metabolism and Diabetes, 2011, Vol 2, Issue 2, p. 7-13