Gastrointestinal hormone

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The gastrointestinal hormones (or gut hormones) constitute a group of hormones secreted by enteroendocrine cells in the stomach, pancreas, and small intestine that control various functions of the digestive organs. Later studies showed that most of the gut peptides, such as secretin, cholecystokinin or substance P, were found to play a role of neurotransmitters and neuromodulators in the central and peripheral nervous systems. [1]

Contents

Enteroendocrine cells do not form glands but are spread throughout the digestive tract. They exert their autocrine and paracrine actions that integrate gastrointestinal function. [2]

Types

The gastrointestinal hormones [3] can be divided into three main groups based upon their chemical structure.

Ghrelin is a peptide hormone released from the stomach and liver and is often referred to as the "hunger hormone" since high levels of it are found in individuals that are fasting. Ghrelin agonistic treatments can be used to treat illnesses such as anorexia and loss of appetites in cancer patients. Ghrelin treatments for obesity are still under intense scrutiny and no conclusive evidence has been reached. This hormone stimulates growth hormone release. Amylin controls glucose homeostasis and gastric motility

Glucose-dependent insulinotropic polypeptide possesses an acute influence on food intake through its effects on adipocytes

Oxyntomodulin plays a role in controlling acid secretion and satiation

Characteristics of prominent forms of principal gut regulatory peptides [4] :1719
Hormone or peptideMolecular weight (Da)Number of amino acidsMain gut localizationPrincipal physiologic actions
Gastrin family
Cholecystokinin 391833 (also 385, 59)Duodenum and jejunum, Enteric nervesStimulates gallbladder contraction and intestinal motility; stimulates secretion of pancreatic enzymes, insulin, glucagon, and pancreatic polypeptides; has a role in indicating satiety; the C-terminal 8 amino acid peptide cholecystokinin (CCK)-8 retains full activity
Little gastrin 209817Both forms of gastrin are found in the gastric antrum and duodenumGastrins stimulate the secretion of gastric acid, pepsinogen, intrinsic factor, and secretin; stimulate intestinal mucosal growth; increase gastric and intestinal motility
Big gastrin 383934
Secretin-glucagon family
Secretin 305627Duodenum and jejunumStimulates pancreatic secretion of HCO3, enzymes and insulin; reduces gastric and duodenal motility, inhibits gastrin release and gastric acid secretion
Vasoactive intestinal polypeptide (VIP)332628Enteric nervesRelaxes smooth muscle of gut, blood vessels, and genitourinary system; increases water and electrolyte secretion from pancreas and gut; releases hormones from pancreas, gut, and hypothalamus
Glucose-dependent insulinotropic 497642Duodenum and jejunumStimulates insulin release; reduces gastric and intestinal motility; increases fluid and electrolyte secretion from small intestine
Brief Description of Some GI Regulatory Peptides [4] :1720
Hormone or peptideMajor tissue locations in the gutPrincipal known actions
Bombesin Throughout the gut and pancreasStimulates release of cholecystokinin (CCK) and gastrin
Calcitonin gene-related peptide Enteric nervesUnclear
Chromogranin A Neuroendocrine cellsSecretory protein
Enkephalins Stomach, duodenumOpiate-like actions
Enteroglucagon Small intestine, pancreasInhibits insulin secretion
Galanin Enteric nerves
Ghrelin StomachStimulates appetite, increases gastric emptying
Glucagon-like peptide 1 Pancreas, ileumIncreases insulin secretion
Glucagon-like peptide 2 Ileum, colonEnterocyte-specific growth hormone
Growth factors Throughout the gutCell proliferation and differentiation
Growth hormone-releasing factor Small intestineUnclear
Leptin StomachAppetite control
Motilin Throughout the gutIncreases gastric emptying and small bowel motility
Neuropeptide Y Enteric nervesRegulation of intestinal blood flow
Neurotensin IleumAffects gut motility; increases jejunal and ileal fluid secretion
Pancreatic polypeptide PancreasInhibits pancreatic and biliary secretion
Peptide YY ColonInhibits food intake
Somatostatin Stomach, pancreasInhibits secretion and action of many hormones
Substance P Enteric nervesUnclear
Trefoil peptides Stomach, intestineMucosal protection and repair

See also

Notes and references

  1. Al-hussaniy, Hany A.; AL-Biati, Haedar A (2022). "The Role of Leptin Hormone, Neuropeptide Y, Ghrelin and Leptin/Ghrelin ratio in Obesogenesis". Medical and Pharmaceutical Journal. 1 (2): 12–23. doi: 10.55940/medphar20227 . ISSN   2957-6067.
  2. "Enteric Endocrine System". www.vivo.colostate.edu. Archived from the original on 2020-06-30. Retrieved 2016-09-16.
  3. Vella A and Drucker DJ (2011)Chapter 39 Gastrointestinal Hormones and Gut Endocrine Tumors, pp 1697-1707. In Williams Textbook of Endocrinology (2011, 12th edition)
  4. 1 2 Burtis CA, Ashwood ER, Bruns DE (2012-10-14). Tietz Textbook of Clinical Chemistry and Molecular Diagnostics, 5th edition. Elsevier Saunders. ISBN   978-1-4160-6164-9.