Enteroglucagon

Enteroglucagon is a historic term used to describe a group of glucagon-related peptides produced in the gut. It refers to peptides derived from the proglucagon gene that are released by intestinal L cells in response to meals and other luminal stimuli. The concept emphasizes the role of the gut as a source of glucagon-family hormones beyond pancreatic glucagon.

Biosynthesis and processing: The GCG gene encodes proglucagon. In pancreatic alpha cells, prohormone convertase 2 (PC2) generates glucagon. In enteroendocrine L cells of the small intestine and colon, proglucagon is processed by PC1/3 to yield several peptides, including glicentin (a 69-amino-acid peptide containing an intact glucagon sequence), glucagon-like peptide-1 (GLP-1), glucagon-like peptide-2 (GLP-2), and oxyntomodulin (OG). Glicentin and related fragments may be released alongside GLP-1 and GLP-2 and were historically referred to as enteroglucagon.

Physiological roles: GLP-1 stimulates insulin secretion in a glucose-dependent manner, inhibits glucagon release, slows gastric emptying, and promotes satiety. GLP-2 supports intestinal growth and mucosal integrity. Oxyntomodulin has activity that can influence appetite and energy expenditure. The precise function of glicentin is less well defined, but it is part of the intestinal glucagon-derived peptide family. Collectively, enteroglucagon peptides act as gut-derived signals that respond to nutrient intake and modulate metabolic and gastrointestinal processes.

Clinical and research relevance: Measurements of enteroglucagon or its constituent peptides are used in metabolic and gut-endocrine research. The strong clinical interest in GLP-1–related pathways has driven therapeutic development (for example, GLP-1 receptor agonists). Today, many researchers prefer naming the specific peptides (GLP-1, GLP-2, glicentin, oxyntomodulin) rather than using the umbrella term enteroglucagon, though the latter remains in historical literature.