Glucagon-like peptide-1



Glucagon-like peptide-1 (GLP-1) is derived from the transcription product of the proglucagon gene. The major source of GLP-1 in the body is the intestinal L cell that secretes GLP-1 as a gut hormone. The biologically active forms of GLP-1 are: GLP-1-(7-37) and GLP-1-(7-36)NH2.GLP-1 is also a neuropeptide (Jin et al., 1988) regulating several neuroendocrine and autonomic responses (Turton et al., 1996)

GLP-1 secretion by L cells is dependent on the presence of nutrients in the lumen of the small intestine. The secretagogues (agents that causes or stimulates secretion) of this hormone include major nutrients like carbohydrate, protein and lipid. Once in the circulation, GLP-1 has a half life of less than 2 minutes, due to rapid degradation by the enzyme dipeptidyl peptidase-4.

Physiological functions
GLP-1 possesses several physiological properties that make it a subject of intensive investigation as a potential treatment of diabetes mellitus. . The known physiological functions of GLP-1 include:
 * increases insulin secretion from the pancreas in a glucose-dependent manner.
 * decreases glucagon secretion from the pancreas.
 * increases beta cells mass and insulin gene expression.
 * inhibits acid secretion and gastric emptying in the stomach.
 * decreases food intake by increasing satiety.