Secretin family

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1gcn opm.png
Identifiers
SymbolHormone_2
Pfam PF00123
InterPro IPR000532
PROSITE PDOC00233
SCOP2 1gcn / SCOPe / SUPFAM
OPM superfamily 145
OPM protein 1gcn

Glucagon/gastric inhibitory polypeptide/secretin/vasoactive intestinal peptide]] hormones are a family of evolutionarily related peptide hormones that regulate activity of G-protein-coupled receptors from the secretin receptor family.

A number of polypeptidic hormones, mainly expressed in the intestine or the pancreas, belong to a group of these structurally related peptides. [1] [2] One such hormone, glucagon, is widely distributed and produced in the alpha-cells of pancreatic islets. [3] It affects glucose metabolism in the liver [4] by inhibiting glycogen synthesis, stimulating glycogenolysis and enhancing gluconeogenesis. It also increases mobilisation of glucose, free fatty acids, and ketone bodies, which are metabolites produced in excess in diabetes mellitus. Glucagon is produced, like other peptide hormones, as part of a larger precursor (preproglucagon), which is cleaved to produce glucagon, glucagon-like protein I, glucagon-like protein II, and glicentin. [5] The structure of glucagon itself is fully conserved in all mammalian species in which it has been studied. [3] Other members of the structurally similar group include secretin, gastric inhibitory peptide, vasoactive intestinal peptide, prealbumin, peptide HI-27, and growth hormone releasing factor.

Human hormones from this family

ADCYAP1; GCG; GHRH; GIP; SCT; VIP;

Related Research Articles

Secretin 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.

Glucagon Peptide hormone

Glucagon is a peptide hormone, produced by alpha cells of the pancreas. It raises concentration of glucose and fatty acids in the bloodstream, and is considered to be the main catabolic hormone of the body. It is also used as a medication to treat a number of health conditions. Its effect is opposite to that of insulin, which lowers extracellular glucose. It is produced from proglucagon, encoded by the GCG gene.

Somatostatin 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.

Gastrin

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.

Digestive enzymes are a group of enzymes that break down polymeric macromolecules into their smaller building blocks, in order to facilitate their absorption by 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.

Vasoactive intestinal peptide Hormone that affects blood pressure / heart rate

Vasoactive intestinal peptide, also known as vasoactive intestinal polypeptide or VIP, is a peptide hormone that is vasoactive in the intestine. VIP is a peptide of 28 amino acid residues that belongs to a glucagon/secretin superfamily, the ligand of class II G protein–coupled receptors. VIP is produced in many tissues of vertebrates including the gut, pancreas, and suprachiasmatic nuclei of the hypothalamus in the brain. VIP stimulates contractility in the heart, causes vasodilation, increases glycogenolysis, lowers arterial blood pressure and relaxes the smooth muscle of trachea, stomach and gallbladder. In humans, the vasoactive intestinal peptide is encoded by the VIP gene.

Incretin 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.

Gastric inhibitory polypeptide

Gastric inhibitory polypeptide (GIP), or gastric inhibitory peptide, also known as glucose-dependent insulinotropic polypeptide, is an inhibiting hormone of the secretin family of hormones. While it is weak inhibitor of gastric acid secretion, its main role is to stimulate insulin secretion.

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.

Proglucagon

Proglucagon is a protein that is cleaved from preproglucagon. Preproglucagon in humans is encoded by the GCG gene.

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.

Enteroendocrine cell

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. Enteroendocrine cells of the intestine are the most numerous endocrine cells of the body. 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. In a sense they are known to act as chemoreceptors, initiating digestive actions and detecting harmful substances and initiating protective responses. Enteroendocrine cells are located in the stomach, in the intestine and in the pancreas. Microbiota plays key roles in the intestinal immune and metabolic responses in these enteroendocrine cells via their fermentation product, acetate.

Secretin receptor

Human secretin receptor is a G protein-coupled receptor which binds secretin and is the leading member of the class B GPCR subfamily.

Peptide PHI

Peptide PHI, also known as peptide histidine isoleucine, is a peptide which functions as a hormone. This peptide contains a composition of 27 amino acids with histidine on the N-terminus and isoleucine on the C-terminus. It was originally isolated from mammalian small intestine amongst mammalian neurons called intramural neurons which function in motor activity of the intestinal walls. An example of this was revealed in a study that demonstrated that this peptide regulates water and electrolyte transportation in the human jejunum; similar to its inhibitory effects on fluid absorption in the small intestine of pigs and rats.

Gastric inhibitory polypeptide receptor

The gastric inhibitory polypeptide receptor (GIP-R), also known as the glucose-dependent insulinotropic polypeptide receptor, is a protein that in humans is encoded by the GIPR gene. GIP-R is a member of the 7-transmembrane protein family, a class of G protein coupled receptors. GIP-R is found on beta-cells in the pancreas where it serves as the receptor for the hormone Gastric inhibitory polypeptide (GIP).

The glucagon receptor family is a group of closely related G-protein coupled receptors which include:

VIPR1 Protein-coding gene in humans

Vasoactive intestinal polypeptide receptor 1 also known as VPAC1, is a protein, that in humans is encoded by the VIPR1 gene. VPAC1 is expressed in the brain (cerebral cortex, hippocampus, amygdala), lung, prostate, peripheral blood leukocytes, liver, small intestine, heart, spleen, placenta, kidney, thymus and testis.

Secretin family receptor proteins, also known as Family B or family 2 of G-protein coupled receptors are regulated by peptide hormones from the glucagon hormone family. The family is different from adhesion G protein-coupled receptors.

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. Mutt V (1988). "Vasoactive intestinal polypeptide and related peptides. Isolation and chemistry". Annals of the New York Academy of Sciences. 527 (1): 1–19. Bibcode:1988NYASA.527....1M. doi:10.1111/j.1749-6632.1988.tb26968.x. PMID   3133967. S2CID   40431562.
  2. Bataille D, Blache P, Mercier F, Jarrousse C, Kervran A, Dufour M, Mangeat P, Dubrasquet M, Mallat A, Lotersztajn S (1988). "Glucagon and related peptides. Molecular structure and biological specificity". Annals of the New York Academy of Sciences. 527 (1): 168–85. Bibcode:1988NYASA.527..168B. doi:10.1111/j.1749-6632.1988.tb26980.x. PMID   3291691. S2CID   7798790.
  3. 1 2 Conlon JM, Thim L (December 1985). "Primary structure of glucagon from an elasmobranchian fish. Torpedo marmorata". General and Comparative Endocrinology. 60 (3): 398–405. doi:10.1016/0016-6480(85)90073-5. PMID   4076759.
  4. Lopez LC, Frazier ML, Su CJ, Kumar A, Saunders GF (September 1983). "Mammalian pancreatic preproglucagon contains three glucagon-related peptides". Proceedings of the National Academy of Sciences of the United States of America. 80 (18): 5485–9. Bibcode:1983PNAS...80.5485L. doi: 10.1073/pnas.80.18.5485 . PMC   384282 . PMID   6577439.
  5. Pollock HG, Hamilton JW, Rouse JB, Ebner KE, Rawitch AB (July 1988). "Isolation of peptide hormones from the pancreas of the bullfrog (Rana catesbeiana). Amino acid sequences of pancreatic polypeptide, oxyntomodulin, and two glucagon-like peptides". The Journal of Biological Chemistry. 263 (20): 9746–51. doi: 10.1016/S0021-9258(19)81581-8 . PMID   3260236.
This article incorporates text from the public domain Pfam and InterPro: IPR000532