Enteroglucagon is a

peptide Peptides (, ) are short chains of amino acids linked by peptide bonds. Long chains of amino acids are called proteins. Chains of fewer than twenty amino acids are called oligopeptides, and include dipeptides, tripeptides, and tetrapeptides. A ...

hormone A hormone (from the Greek participle , "setting in motion") is a class of signaling molecules in multicellular organisms that are sent to distant organs by complex biological processes to regulate physiology and behavior. Hormones are required ...

derived from

preproglucagon Proglucagon is a protein that is cleaved from preproglucagon. Preproglucagon in humans is encoded by the ''GCG'' gene. Proglucagon is a precursor of glucagon, and several other components. It is generated in the alpha cells of the pancreas and in ...

. It is a gastrointestinal hormone, secreted from mucosal cells primarily of the colon and terminal

ileum The ileum () is the final section of the small intestine in most higher vertebrates, including mammals, reptiles, and birds. In fish, the divisions of the small intestine are not as clear and the terms posterior intestine or distal intestine ma ...

. It consists of 37 amino acids. Enteroglucagon is released when fats and glucose are present in the small intestine; which decrease the motility to allow sufficient time for these nutrients to be absorbed.

Discovery

In 1948, Sutherland and De Duve identified a gastrointestinal glucagon-like material in gastric mucosa, the term "enteroglucagon" was used to describe this material that shared a similar immunoreactivity with glucagon. A half-century later, Brubaker and Drucker studied

proglucagon Proglucagon is a protein that is cleaved from preproglucagon. Preproglucagon in humans is encoded by the ''GCG'' gene. Proglucagon is a precursor of glucagon, and several other components. It is generated in the alpha cells of the pancreas and in ...

gene expression, they discovered the function of enteroglucagon is related to the growth of intestinal epithelium.

Function

Enteroglucagon is a proglucagon-derived peptide or enteroendocrine cells derived peptide in the small intestine. Preproglucagon undergoes

post translational modification Post-translational modification (PTM) is the covalent and generally enzymatic modification of proteins following protein biosynthesis. This process occurs in the endoplasmic reticulum and the golgi apparatus. Proteins are synthesized by ribosome ...

to release glucagon-like peptides (GLP-1 and GLP-2) and other molecules derived from L-cells of intestine. GLP-1 is derived from a class of intestinal hormones called

incretin Incretins are a group of metabolic hormones that stimulate a decrease in blood glucose levels. Incretins are released after eating and augment the secretion of insulin released from pancreatic beta cells of the islets of Langerhans by a blood-gl ...

and the molecule exists in two forms GLP-1(7-37) and GLP-1(7-36) amide. GLP-1 form of incretin starts circulating in response to a high blood glucose level. Incretin effect is a

negative feedback loop Negative feedback (or balancing feedback) occurs when some function of the output of a system, process, or mechanism is fed back in a manner that tends to reduce the fluctuations in the output, whether caused by changes in the input or by other ...

between glucose and insulin level, it promotes insulin release from beta cells of pancreas islet and suppresses glucagon when the glucose level is high. In vertebrate mammals, GLP-2 sequences are highly conversed in the intestine. The molecule functions as apart of adaptive response, such that contributes intestinal growth, proliferation effect, intestinal dilation (increases the mucosal blood flow) and reduces the chance of apoptosis.

Clinical Significance

GLP-1 is effective at reducing blood glucose levels. GLP-1 analogs have a significant therapeutic effect and high efficacy on diabetes treatments and

hypoglycemia Hypoglycemia, also called low blood sugar, is a fall in blood sugar to levels below normal, typically below 70 mg/dL (3.9 mmol/L). Whipple's triad is used to properly identify hypoglycemic episodes. It is defined as blood glucose belo ...

prevention. Proliferation effect and trophic effect on the small intestine, GLP-2 is used as a therapy to support patients with short-bowel syndrome and other underlying intestinal conditions.

References

External links

Overview at colostate.edu
* * Peptide hormones {{biochemistry-stub

Discovery

Function

Clinical Significance

See also

References

External links