Physiology of GLP-1 and its role in the pathophysiology of type 2 diabetes

Glucagon-like peptide-1 (GLP-1) is a gut hormone synthesized in intestinal L cells, whose secretion depends on the presence of nutrients in the small intestinal lumen. Once in the circulation, GLP-1 is rapidly degraded by dipeptidyl peptidase-4 (DPP-4) , resulting in a half-life of only a few minutes.

The physiological function of GLP-1 is primarily focused on controlling blood glucose concentration, but it also plays multiple roles in metabolic homeostasis following nutrient absorption. Its biological activities include stimulation of glucose-dependent insulin secretion and insulin biosynthesis, inhibition of glucagon secretion and gastric emptying, and suppression of food intake.

GLP-1 can lower blood glucose levels in diabetic patients. This finding, along with other data demonstrating that GLP-1 can restore β-cell sensitivity to exogenous secretagogues, suggests that enhancing GLP-1 signaling is a useful therapeutic strategy for patients with type 2 diabetes.

Glucagon-like peptide-1 (GLP-1) is a hormone synthesized and secreted by intestinal L cells following food ingestion. Once in the systemic circulation, GLP-1 is degraded by dipeptidyl peptidase-4, resulting in a half-life of 2-3 minutes.

The physiological role of GLP-1 is to control blood glucose concentration, although it also plays various other metabolic roles following nutrient absorption. GLP-1’ s biological activities include stimulation of insulin biosynthesis and glucose-dependent insulin secretion in pancreatic β-cells, inhibition of glucagon secretion, delayed gastric emptying, and suppression of food intake.

GLP-1 can lower blood glucose levels in patients with type 2 diabetes and restore β-cell sensitivity to exogenous secretagogues, suggesting that increasing GLP-1 levels may be a useful therapeutic strategy for treating patients with type 2 diabetes.