A hormone first characterized in the 1980s has become the foundation of a major transformation in how physicians manage diabetes and obesity. As of October 11, 2024, glucagon-like peptide-1, abbreviated as GLP-1, remains a focal point for researchers examining its role in regulating blood sugar. While the underlying science is not new, its practical applications continue to expand.
GLP-1 is a peptide hormone derived from the larger proglucagon peptide, which is broken down into smaller active components. The body produces GLP-1 in intestinal enteroendocrine L-cells and in specific neurons located in the brainstem.
This production occurs after food consumption. The hormone then works to reduce blood glucose levels through a distinctive mechanism: it stimulates insulin secretion only when glucose concentrations are elevated. This glucose-dependent action avoids the dangerous low blood sugar episodes associated with some older diabetes medications, making GLP-1 an attractive target for pharmaceutical development. The hormone’s structure is precise, containing either 30 or 31 amino acids.
Its initial form, GLP-1 (1–37), undergoes amidation and proteolytic cleavage to yield two biologically active versions: GLP-1 (7–36) amide and GLP-1 (7–37). Both possess a secondary structure composed of two α-helices separated by a linker region, a configuration that enables the hormone to bind to its receptors and influence glucose metabolism.
GLP-1 belongs to a class of hormones known as incretins, which are substances released from the gut that enhance insulin secretion after meals. Another incretin, glucose-dependent insulinotropic peptide (GIP), performs a similar function. However, a critical distinction exists: in patients with type 2 diabetes, GIP’s effect is reduced, while GLP-1’s action remains intact.
This preservation established GLP-1 as a valuable therapeutic target. The insulinotropic effects of GLP-1 are well-documented and form the basis for GLP-1 receptor agonists, a class of drugs that mimic the hormone and activate its receptor.
These medications are now widely prescribed for both diabetes and obesity, with their market growing rapidly in recent years. Beyond insulin stimulation, research indicates that GLP-1 has regulatory and protective effects on the body, though the full scope of these effects and their mechanisms remain under investigation. The history of GLP-1 research dates to the 1980s, when the hormone was first sequenced and its activity described.
Early studies focused on its incretin role, while later work revealed its potential for weight loss by slowing gastric emptying and signaling satiety in the brain. This dual action on glucose and appetite drove pharmaceutical interest.
By October 2024, GLP-1 receptor agonists rank among the most prescribed drugs for metabolic conditions, as the medical community continues to explore optimal usage, patient selection, and duration of treatment.
