GLP-1 (Glucagon-Like Peptide-1)
Also known as: Glucagon-Like Peptide-1
GLP-1 is an endogenous gut-derived incretin hormone that stimulates insulin secretion in response to food intake. Semaglutide and Tirzepatide are GLP-1 receptor agonists developed as anti-diabetic and weight-loss therapeutics.
Overview
GLP-1 is secreted by intestinal L-cells in response to food, particularly carbohydrates and fats. It enhances glucose-dependent insulin secretion from pancreatic beta cells, suppresses glucagon, slows gastric emptying, and acts on hypothalamic satiety centers to reduce appetite. Endogenous GLP-1 has a very short half-life (~2 minutes) due to DPP-IV enzyme degradation. GLP-1 receptor agonists like Semaglutide overcome this by using structural modifications that resist degradation and bind albumin, extending half-life to approximately 7 days. Tirzepatide additionally activates the GIP receptor, making it a dual incretin agonist with enhanced metabolic effects. Both compounds are FDA-approved and represent the most clinically significant peptide-based therapeutics of the 2020s.
Related Peptide Profiles
Frequently asked questions
What does GLP-1 do in the body?+
GLP-1 stimulates insulin release (only when glucose is elevated), suppresses glucagon, slows gastric emptying, and reduces appetite. These combined effects lower blood glucose and promote satiety.
How are GLP-1 receptor agonists different from natural GLP-1?+
Natural GLP-1 degrades within 2 minutes. GLP-1 receptor agonists like Semaglutide are chemically modified to resist degradation and have half-lives of approximately 7 days, allowing weekly dosing.
Is Tirzepatide a GLP-1 agonist?+
Tirzepatide is a dual GIP/GLP-1 receptor agonist — it activates both the GLP-1 receptor and the glucose-dependent insulinotropic polypeptide (GIP) receptor, producing superior glycemic and weight outcomes compared to GLP-1 alone.