Enteroendocrine cell

Last updated
Enteroendocrine cell
Digestive hormones.jpg
Actions of the major digestive hormones secreted by enteroendocrine cells
Details
System Endocrine system
Location Gastrointestinal tract
Identifiers
Latin endocrinocyti gastroenteropancreatici
MeSH D019858
TH H3.04.02.0.00024, H3.08.01.0.00003
FMA 62930
Anatomical terms of microanatomy

Enteroendocrine cells are specialized cells of the gastrointestinal tract and pancreas with endocrine function. They produce gastrointestinal hormones or peptides in response to various stimuli and release them into the bloodstream for systemic effect, diffuse them as local messengers, or transmit them to the enteric nervous system to activate nervous responses. [1] [2] Enteroendocrine cells of the intestine are the most numerous endocrine cells of the body. [3] [4] [5] They constitute an enteric endocrine system as a subset of the endocrine system just as the enteric nervous system is a subset of the nervous system. [6] In a sense they are known to act as chemoreceptors, initiating digestive actions and detecting harmful substances and initiating protective responses. [7] [8] Enteroendocrine cells are located in the stomach, in the intestine and in the pancreas. Microbiota play key roles in the intestinal immune and metabolic responses in these enteroendocrine cells via their fermentation product (short chain fatty acid), acetate. [9]

Contents

Intestinal enteroendocrine cells

Intestinal enteroendocrine cells are not clustered together but spread as single cells throughout the intestinal tract. [7]

Hormones secreted include somatostatin, motilin, cholecystokinin, neurotensin, vasoactive intestinal peptide, and enteroglucagon. [10] The enteroendocrine cells sense the metabolites from intestinal commensal microbiota and, in turn, coordinate antibacterial, mechanical, and metabolic branches of the host intestinal innate immune response to the commensal microbiota. [11]

K cell

K cells secrete gastric inhibitory peptide, an incretin, which also promotes triglyceride storage. [12] K cells are mostly found in the duodenum. [13]

L cell

L cells secrete glucagon-like peptide-1, an incretin, peptide YY3-36, oxyntomodulin and glucagon-like peptide-2. L cells are primarily found in the ileum and large intestine (colon), but some are also found in the duodenum and jejunum. [14]

I cell

I cells secrete cholecystokinin (CCK), and have the highest mucosal density in the duodenum with a decreasing amount throughout the small intestine. [15] They modulate bile secretion, exocrine pancreas secretion, and satiety. [16]

G cell

Stomach enteroendocrine cells, which release gastrin, and stimulate gastric acid secretion. [17]

Enterochromaffin cell

Enterochromaffin cells are enteroendocrine and neuroendocrine cells with a close similarity to adrenomedullary chromaffin cells secreting serotonin. [18]

Enterochromaffin-like cell

Enterochromaffin-like cells or ECL cells are a type of neuroendocrine cell secreting histamine.

N cell

Located in a increasing manner throughout the small intestine, with the highest levels found in the in ileum, [19] N cells release neurotensin, and control smooth muscle contraction. [20]

S cell

S cells secrete secretin mostly from the duodenum, but also in decreasing amounts throughout the rest of the small intestine, [21] and stimulate exocrine pancreatic secretion. [16]

D cell

Also called Delta cells, D cells secrete somatostatin.

Mo cell (or M cell)

Gastric enteroendocrine cells

Gastric enteroendocrine cells are found in the gastric glands, mostly at their base. The G cells secrete gastrin, post-ganglionic fibers of the vagus nerve can release gastrin-releasing peptide during parasympathetic stimulation to stimulate secretion. Enterochromaffin-like cells are enteroendocrine and neuroendocrine cells also known for their similarity to chromaffin cells secreting histamine, which stimulates G cells to secrete gastrin.

Other hormones produced include cholecystokinin, somatostatin, vasoactive intestinal peptide, substance P, alpha and gamma-endorphin. [10] [24]

Pancreatic enteroendocrine cells

Pancreatic enteroendocrine cells are located in the islets of Langerhans and produce most importantly the hormones insulin and glucagon. The autonomous nervous system strongly regulates their secretion, with parasympathetic stimulation stimulating insulin secretion and inhibiting glucagon secretion and sympathetic stimulation having opposite effect. [25]

Other hormones produced include somatostatin, pancreatic polypeptide, amylin and ghrelin.

Clinical significance

Rare and slow growing carcinoid and non-carcinoid tumors develop from these cells. When a tumor arises it has the capacity to secrete large volumes of hormones. [2] [26]

History

The very discovery of hormones occurred during studies of how the digestive system regulates its activities, as explained at Secretin § Discovery .

Other organisms

In rats ( Rattus rattus ) the short-chain fatty acid receptor GPR43 is expressed both by this cell type and by mast cells of the mucosa. [27]

See also

Related Research Articles

<span class="mw-page-title-main">Pancreas</span> Organ of the digestive system and endocrine system of vertebrates

The pancreas is an organ of the digestive system and endocrine system of vertebrates. In humans, it is located in the abdomen behind the stomach and functions as a gland. The pancreas is a mixed or heterocrine gland, i.e., it has both an endocrine and a digestive exocrine function. 99% of the pancreas is exocrine and 1% is endocrine. As an endocrine gland, it functions mostly to regulate blood sugar levels, secreting the hormones insulin, glucagon, somatostatin and pancreatic polypeptide. As a part of the digestive system, it functions as an exocrine gland secreting pancreatic juice into the duodenum through the pancreatic duct. This juice contains bicarbonate, which neutralizes acid entering the duodenum from the stomach; and digestive enzymes, which break down carbohydrates, proteins and fats in food entering the duodenum from the stomach.

<span class="mw-page-title-main">Secretin</span> Hormone involved in stomach, pancreas and liver secretions

Secretin is a hormone that regulates water homeostasis throughout the body and influences the environment of the duodenum by regulating secretions in the stomach, pancreas, and liver. It is a peptide hormone produced in the S cells of the duodenum, which are located in the intestinal glands. In humans, the secretin peptide is encoded by the SCT gene.

<span class="mw-page-title-main">Delta cell</span>

Delta cells are somatostatin-producing cells. They can be found in the stomach, intestine and the pancreatic islets. Delta cells comprise ca 5% of the cells in the islets but may interact with many more islet cells than suggested by their low numbers. In rodents, delta-cells are located in the periphery of the islets; in humans the islet architecture is generally less organized and delta-cells are frequently observed inside the islets as well. In both species, the peptide hormone Urocortin III (Ucn3) is a major local signal that is released from beta cells to induce the local secretion of somatostatin. It has also been suggested that somatostatin may be implicated in insulin-induced hypoglycaemia through a mechanism involving SGLT-2 receptors. Ghrelin can also strongly stimulate somatostatin secretion, thus indirectly inhibiting insulin release. Viewed under an electron microscope, delta-cells can be identified as cells with smaller and slightly more compact granules than beta cells.

<span class="mw-page-title-main">Somatostatin</span> Peptide hormone that regulates the endocrine system

Somatostatin, also known as growth hormone-inhibiting hormone (GHIH) or by several other names, is a peptide hormone that regulates the endocrine system and affects neurotransmission and cell proliferation via interaction with G protein-coupled somatostatin receptors and inhibition of the release of numerous secondary hormones. Somatostatin inhibits insulin and glucagon secretion.

<span class="mw-page-title-main">Cholecystokinin</span> Hormone of the gastrointestinal system

Cholecystokinin is a peptide hormone of the gastrointestinal system responsible for stimulating the digestion of fat and protein. Cholecystokinin, formerly called pancreozymin, is synthesized and secreted by enteroendocrine cells in the duodenum, the first segment of the small intestine. Its presence causes the release of digestive enzymes and bile from the pancreas and gallbladder, respectively, and also acts as a hunger suppressant.

<span class="mw-page-title-main">Gastrin</span> Mammalian protein found in Homo sapiens

Gastrin is a peptide hormone that stimulates secretion of gastric acid (HCl) by the parietal cells of the stomach and aids in gastric motility. It is released by G cells in the pyloric antrum of the stomach, duodenum, and the pancreas.

<span class="mw-page-title-main">Gastric acid</span> Digestive fluid formed in the stomach

Gastric acid, gastric juice, or stomach acid is a digestive fluid formed within the stomach lining. With a pH between 1.5 and 3, gastric acid plays a key role in digestion of proteins by activating digestive enzymes, which together break down the long chains of amino acids of proteins. Gastric acid is regulated in feedback systems to increase production when needed, such as after a meal. Other cells in the stomach produce bicarbonate, a base, to buffer the fluid, ensuring a regulated pH. These cells also produce mucus – a viscous barrier to prevent gastric acid from damaging the stomach. The pancreas further produces large amounts of bicarbonate and secretes bicarbonate through the pancreatic duct to the duodenum to neutralize gastric acid passing into the digestive tract.

<span class="mw-page-title-main">Digestive enzyme</span> Class of enzymes

Digestive enzymes are a group of enzymes that break down polymeric macromolecules into their smaller building blocks, in order to facilitate their absorption into the cells of the body. Digestive enzymes are found in the digestive tracts of animals and in the tracts of carnivorous plants, where they aid in the digestion of food, as well as inside cells, especially in their lysosomes, where they function to maintain cellular survival. Digestive enzymes of diverse specificities are found in the saliva secreted by the salivary glands, in the secretions of cells lining the stomach, in the pancreatic juice secreted by pancreatic exocrine cells, and in the secretions of cells lining the small and large intestines.

<span class="mw-page-title-main">Incretin</span> Group of gastrointestinal hormones

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-glucose–dependent mechanism.

<span class="mw-page-title-main">Glucose-dependent insulinotropic polypeptide</span> Mammalian protein found in Homo sapiens

Glucose-dependent insulinotropic polypeptide, abbreviated as GIP, is an inhibiting hormone of the secretin family of hormones. While it is a weak inhibitor of gastric acid secretion, its main role, being an incretin, is to stimulate insulin secretion.

<span class="mw-page-title-main">Motilin</span>

Motilin is a 22-amino acid polypeptide hormone in the motilin family that, in humans, is encoded by the MLN gene.

Enteroglucagon is a peptide hormone derived from preproglucagon. It is a gastrointestinal hormone, secreted from mucosal cells primarily of the colon and terminal ileum. 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.

<span class="mw-page-title-main">Gastrinoma</span> Medical condition

Gastrinomas are neuroendocrine tumors (NETs), usually located in the duodenum or pancreas, that secrete gastrin and cause a clinical syndrome known as Zollinger–Ellison syndrome (ZES). A large number of gastrinomas develop in the pancreas or duodenum, with near-equal frequency, and approximately 10% arise as primary neoplasms in lymph nodes of the pancreaticoduodenal region.

<span class="mw-page-title-main">Pancreatic polypeptide</span> Protein produced by the endocrine pancreas

Pancreatic polypeptide (PP) is a polypeptide secreted by PP cells in the endocrine pancreas. It regulates pancreatic secretion activities, and also impacts liver glycogen storage and gastrointestinal secretion. Its secretion may be impacted by certain endocrine tumours.

<span class="mw-page-title-main">Glucagon-like peptide-1</span> Gastrointestinal peptide hormone Involved in glucose homeostasis

Glucagon-like peptide-1 (GLP-1) is a 30- or 31-amino-acid-long peptide hormone deriving from the tissue-specific posttranslational processing of the proglucagon peptide. It is produced and secreted by intestinal enteroendocrine L-cells and certain neurons within the nucleus of the solitary tract in the brainstem upon food consumption. The initial product GLP-1 (1–37) is susceptible to amidation and proteolytic cleavage, which gives rise to the two truncated and equipotent biologically active forms, GLP-1 (7–36) amide and GLP-1 (7–37). Active GLP-1 protein secondary structure includes two α-helices from amino acid position 13–20 and 24–35 separated by a linker region.

Somatostatinomas are a tumor of the delta cells of the endocrine pancreas that produces somatostatin. Increased levels of somatostatin inhibit pancreatic hormones and gastrointestinal hormones. Thus, somatostatinomas are associated with mild diabetes mellitus, steatorrhoea and gallstones, and achlorhydria. Somatostatinomas are commonly found in the head of pancreas. Only ten percent of somatostatinomas are functional tumours [9], and 60–70% of tumours are malignant. Nearly two-thirds of patients with malignant somatostatinomas will present with metastatic disease.

The gastrointestinal 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.

The enterogastric reflex is one of the three extrinsic reflexes of the gastrointestinal tract, the other two being the gastroileal reflex and the gastrocolic reflex. The enterogastric reflex is stimulated by duodenal distension. It can also be stimulated by a pH of 3-4 in the duodenum and by a pH of 1.5 in the stomach. Upon initiation of the reflex, the release of gastrin by G-cells in the antrum of the stomach is shut off. This in turn inhibits gastric motility and the secretion of gastric acid (HCl).

The nervous system, and endocrine system collaborate in the digestive system to control gastric secretions, and motility associated with the movement of food throughout the gastrointestinal tract, including peristalsis, and segmentation contractions.

Local hormones are a large group of signaling molecules that do not circulate within the blood. Local hormones are produced by nerve and gland cells and bind to either neighboring cells or the same type of cell that produced them. Local hormones are activated and inactivated quickly. They are released during physical work and exercise. They mainly control smooth and vascular muscle dilation. Strength of response is dependent upon the concentration of receptors of target cell and the amount of ligand.

References

  1. ↑ Rehfeld JF (October 1998). "The new biology of gastrointestinal hormones". Physiological Reviews. 78 (4): 1087–108. doi:10.1152/physrev.1998.78.4.1087. PMID   9790570.
  2. 1 2 Solcia E, Capella C, Buffa R, Usellini L, Fiocca R, Frigerio B, Tenti P, Sessa F (1981). "The diffuse endocrine-paracrine system of the gut in health and disease: ultrastructural features". Scandinavian Journal of Gastroenterology. Supplement. 70: 25–36. PMID   6118945.
  3. ↑ Ahlman H (2001). "The gut as the largest endocrine organ in the body". Annals of Oncology. 12 Suppl 2 (suppl 2): S63–8. doi: 10.1093/annonc/12.suppl_2.s63 . PMID   11762354.
  4. ↑ Schonhoff SE, Giel-Moloney M, Leiter AB (June 2004). "Minireview: Development and differentiation of gut endocrine cells". Endocrinology. 145 (6): 2639–44. doi: 10.1210/en.2004-0051 . PMID   15044355. Archived from the original on 2013-05-02. Retrieved 2013-03-01.
  5. ↑ Moran GW, Leslie FC, Levison SE, Worthington J, McLaughlin JT (July 2008). "Enteroendocrine cells: neglected players in gastrointestinal disorders?". Therapeutic Advances in Gastroenterology. 1 (1): 51–60. doi:10.1177/1756283X08093943. PMC   3002486 . PMID   21180514.
  6. ↑ Wallace Hayes A (2007). Principles and Methods of Toxicology (5th, revised ed.). CRC Press. p. 1547. ISBN   9781420005424.
  7. 1 2 Sternini C, Anselmi L, Rozengurt E (February 2008). "Enteroendocrine cells: a site of 'taste' in gastrointestinal chemosensing". Current Opinion in Endocrinology, Diabetes and Obesity. 15 (1): 73–8. doi:10.1097/MED.0b013e3282f43a73. PMC   2943060 . PMID   18185066.
  8. ↑ Sternini C (February 2007). "Taste receptors in the gastrointestinal tract. IV. Functional implications of bitter taste receptors in gastrointestinal chemosensing". American Journal of Physiology. Gastrointestinal and Liver Physiology. 292 (2): G457–61. doi:10.1152/ajpgi.00411.2006. PMID   17095755.
  9. ↑ Jugder BE, Kamareddine L, Watnick PI (August 2021). "Microbiota-derived acetate activates intestinal innate immunity via the Tip60 histone acetyltransferase complex". Immunity. 54 (8): 1683–1697.e3. doi:10.1016/j.immuni.2021.05.017. ISSN   1074-7613. PMC   8363570 . PMID   34107298.
  10. 1 2 Krause WJ, Yamada J, Cutts JH (June 1985). "Quantitative distribution of enteroendocrine cells in the gastrointestinal tract of the adult opossum, Didelphis virginiana". Journal of Anatomy. 140 (4): 591–605. PMC   1165084 . PMID   4077699.
  11. ↑ Watnick PI, Jugder BE (February 2020). "Microbial Control of Intestinal Homeostasis via Enteroendocrine Cell Innate Immune Signaling". Trends Microbiol. 28 (2): 141–149. doi:10.1016/j.tim.2019.09.005. ISSN   0966-842X. PMC   6980660 . PMID   31699645.
  12. ↑ Parker HE, Habib AM, Rogers GJ, Gribble FM, Reimann F (February 2009). "Nutrient-dependent secretion of glucose-dependent insulinotropic polypeptide from primary murine K cells". Diabetologia. 52 (2): 289–298. doi:10.1007/s00125-008-1202-x. PMC   4308617 . PMID   19082577.
  13. ↑ Gutierrez-Aguilar, Ruth; Woods, Stephen C (February 2011). "Nutrition and L and K-enteroendocrine cells". Current Opinion in Endocrinology, Diabetes & Obesity. 18 (1): 35–41. doi:10.1097/MED.0b013e32834190b5. PMC   3884637 . PMID   21124210.
  14. ↑ Drucker DJ, Nauck MA (November 2006). "The incretin system: glucagon-like peptide-1 receptor agonists and dipeptidyl peptidase-4 inhibitors in type 2 diabetes" (PDF). Lancet. 368 (9548): 1696–705. doi:10.1016/s0140-6736(06)69705-5. PMID   17098089. S2CID   25748028. Archived from the original (PDF) on 2014-12-31. Retrieved 2014-12-31.
  15. ↑ Gilliam-Vigh, Hannah; Jorsal, Tina; Rehfeld, Jens F.; Pedersen, Jens; Poulsen, Steen S.; Vilsbøll, Tina; Knop, Filip K. (2021). "Expression of Cholecystokinin and its Receptors in the Intestinal Tract of Type 2 Diabetes Patients and Healthy Controls". The Journal of Clinical Endocrinology & Metabolism. 106 (8): 2164–2170. doi: 10.1210/clinem/dgab367 . PMID   34036343. S2CID   235203208 . Retrieved 2023-09-20.
  16. 1 2 Brubaker PL (July 2012). "A beautiful cell (or two or three?)". Endocrinology. 153 (7): 2945–8. doi: 10.1210/en.2012-1549 . PMID   22730282.
  17. ↑ Friis-Hansen L, Sundler F, Li Y, Gillespie PJ, Saunders TL, Greenson JK, Owyang C, Rehfeld JF, Samuelson LC (March 1998). "Impaired gastric acid secretion in gastrin-deficient mice". The American Journal of Physiology. 274 (3 Pt 1): G561–8. doi:10.1152/ajpgi.1998.274.3.G561. PMID   9530158.
  18. ↑ Ormsbee HS, Fondacaro JD (March 1985). "Action of serotonin on the gastrointestinal tract". Proceedings of the Society for Experimental Biology and Medicine. 178 (3): 333–8. doi:10.3181/00379727-178-42016. PMID   3919396. S2CID   34829257.
  19. ↑ Gilliam-Vigh, Hannah; Jorsal, Tina; Nielsen, Sophie W.; Forman, Julie L.; Pedersen, Jens; Poulsen, Steen S.; Vilsbøll, Tina; Knop, Filip K. (2023). "Expression of Neurotensin and Its Receptors Along the Intestinal Tract in Type 2 Diabetes Patients and Healthy Controls". The Journal of Clinical Endocrinology & Metabolism. 108 (9): 2211–2216. doi:10.1210/clinem/dgad146. PMID   36916883. S2CID   257506286 . Retrieved 2023-09-20.
  20. ↑ Kitabgi P, Freychet P (August 1978). "Effects of neurotensin on isolated intestinal smooth muscles". European Journal of Pharmacology. 50 (4): 349–57. doi:10.1016/0014-2999(78)90140-1. PMID   699961.
  21. ↑ Gilliam-Vigh, Hannah; Jorsal, Tina; Nielsen, Sophie W.; Forman, Julie L.; Pedersen, Jens; Poulsen, Steen S.; Vilsbøll, Tina; Knop, Filip K. (2023). "Expression of Secretin and its Receptor Along the Intestinal Tract in Type 2 Diabetes Patients and Healthy Controls". The Journal of Clinical Endocrinology & Metabolism. doi: 10.1210/clinem/dgad372 . PMID   37335970. S2CID   259202375 . Retrieved 2023-09-20.
  22. ↑ Daniel EE (1990-12-11). Neuropeptide Function in the Gastrointestinal Tract. CRC Press. ISBN   9780849361586.
  23. ↑ Goswami C, Shimada Y, Yoshimura M, Mondal A, Oda S, Tanaka T, Sakai T, Sakata I (2015-06-26). "Motilin Stimulates Gastric Acid Secretion in Coordination with Ghrelin in Suncus murinus". PLOS ONE. 10 (6): e0131554. Bibcode:2015PLoSO..1031554G. doi: 10.1371/journal.pone.0131554 . PMC   4482737 . PMID   26115342.
  24. ↑ Zverkov IV, Vinogradov VA, Smagin VG (October 1983). "[Endorphin-containing cells in the gastric antral mucosa in duodenal ulcer]". Biulleten' Eksperimental'noi Biologii I Meditsiny. 96 (10): 32–4. PMID   6194833.
  25. ↑ Kiba T (August 2004). "Relationships between the autonomic nervous system and the pancreas including regulation of regeneration and apoptosis: recent developments". Pancreas. 29 (2): e51–8. doi:10.1097/00006676-200408000-00019. PMID   15257115. S2CID   15849806.
  26. ↑ Warner RR (May 2005). "Enteroendocrine tumors other than carcinoid: a review of clinically significant advances". Gastroenterology. 128 (6): 1668–84. doi: 10.1053/j.gastro.2005.03.078 . PMID   15887158.
  27. ↑ Camilleri M (October 2012). "Peripheral mechanisms in irritable bowel syndrome". N Engl J Med. 367 (17): 1626–35. doi:10.1056/NEJMra1207068. ISSN   0028-4793. PMID   23094724.
This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.