GLP-1, or glucagon-like peptide-1, is a hormone consisting of 30 or 31 amino acids produced mainly by intestinal L-cells and certain brain neurons in response to food intake

. It functions as an incretin hormone, meaning it enhances insulin secretion from the pancreas in a glucose-dependent manner, thereby helping to lower blood sugar levels after eating

. GLP-1 also inhibits glucagon secretion, slows gastric emptying, and reduces appetite, which contributes to weight loss

. Endogenously, GLP-1 has a very short half-life of about 2 minutes because it is rapidly degraded by enzymes like dipeptidyl peptidase-4 (DPP-4)

. To harness its beneficial effects, GLP-1 receptor agonists-medications that mimic GLP-1-have been developed and are widely used to treat type 2 diabetes and obesity. These drugs stimulate insulin release, suppress glucagon, slow gastric emptying, and reduce food intake, improving blood sugar control and promoting weight loss

. In summary, GLP-1 is a natural hormone that plays a key role in regulating blood glucose and appetite, and its synthetic analogs are important therapeutic agents for diabetes and obesity management