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Neurogastroenterology and Motility Jun 2017Enterochromaffin cells were the first endocrine cells of the gastrointestinal tract to be chemically distinguished, almost 150 years ago. It is now known that the... (Review)
Review
Enterochromaffin cells were the first endocrine cells of the gastrointestinal tract to be chemically distinguished, almost 150 years ago. It is now known that the chromaffin reaction of these cells was due to their content of the reactive aromatic amine, 5-hydroxytryptamine (5-HT, also known as serotonin). They have commonly been thought to be a special class of gut endocrine cells (enteroendocrine cells) that are distinct from the enteroendocrine cells that contain peptide hormones. The study by Martin et al. in the current issue of this journal reveals that the patterns of expression of nutrient receptors and transporters differ considerably between chromaffin cells of the mouse duodenum and colon. However, even within regions, chromaffin cells differ; in the duodenum there are chromaffin cells that contain both secretin and 5-HT, cholecystokinin and 5-HT, and all three of secretin, cholecystokinin, and 5-HT. Moreover, the ratios of these different cell types differ substantially between species. And, in terms of function, 5-HT has many roles, including in appetite, motility, fluid secretion, release of digestive enzymes and bone metabolism. The paper thus emphasizes the need to define the many different classes of enterochromaffin cells and relate this to their roles.
Topics: Animals; Celiac Disease; Enterochromaffin Cells; Gastrointestinal Tract; Humans; Irritable Bowel Syndrome
PubMed: 28485065
DOI: 10.1111/nmo.13101 -
Scientific Reports Feb 2019Peripheral serotonin (5-hydroxytryptamine: 5-HT) synthesized in the intestine by enterochromaffin cells (ECs), plays an important role in the regulation of peristaltic...
Peripheral serotonin (5-hydroxytryptamine: 5-HT) synthesized in the intestine by enterochromaffin cells (ECs), plays an important role in the regulation of peristaltic of the gut, epithelial secretion and promotes the development and maintenance of the enteric neurons. Recent studies showed that the indigenous gut microbiota modulates 5-HT signalling and that ECs use sensory receptors to detect dietary and microbiota-derived signals from the lumen to subsequently transduce the information to the nervous system. We hypothesized that Clostridium ramosum by increasing gut 5-HT availability consequently contributes to high-fat diet-induced obesity. Using germ-free mice and mice monoassociated with C. ramosum, intestinal cell lines and mouse organoids, we demonstrated that bacterial cell components stimulate host 5-HT secretion and program the differentiation of colonic intestinal stem progenitors toward the secretory 5-HT-producing lineage. An elevated 5-HT level regulates the expression of major proteins involved in intestinal fatty acid absorption in vitro, suggesting that the presence of C. ramosum in the gut promotes 5-HT secretion and thereby could facilitates intestinal lipid absorption and the development of obesity.
Topics: Animals; Cell Line; Enterochromaffin Cells; Firmicutes; Mice; Organoids; Serotonin; Serotonin Receptor Agonists
PubMed: 30718836
DOI: 10.1038/s41598-018-38018-z -
American Journal of Surgery Jul 1996The interaction between adrenergic nerves and enterochromaffin (EC) cells was studied in health and disease using animal models and patients with the midgut carcinoid... (Review)
Review
BACKGROUND
The interaction between adrenergic nerves and enterochromaffin (EC) cells was studied in health and disease using animal models and patients with the midgut carcinoid syndrome.
METHODS
The methods included morphological techniques (fluorescence microscopy/cytofluorimetry, electronmicroscopy), experimental models (in vivo/in vitro nerve stimulation, pharmacological analyses, axonal transport, tumor transplantation, tumor cell cultures) and clinical tests (pentagastrin provocation, octreotide scintigraphy).
RESULTS
From vagal nerve stimulation studies it was clear that activation of adrenergic fibers could release serotonin (5-HT) from EC cells, which led to the mapping of a vagal adrenergic pathway. Ultrastructurally a direct innervation of EC cells was demonstrated. It was confirmed in vitro that adrenoceptors controlled the release of 5-HT; it was maintained in neoplasia as studied in the tumor models. The tumor cells shared several functional and morphological characteristics with adrenergic neurons and exerted trophic actions on neurons grown in co-culture.
CONCLUSIONS
Pentagastrin provocation of 5-HT release in carcinoid patients may be mediated via release of catecholamines from the adrenals in turn activating adrenoceptors on tumor cells. Pretreatment with a somatostatin analog can reduce these reactions and thus minimize the risk for carcinoid crisis during surgery.
Topics: Adrenergic Fibers; Animals; Carcinoid Tumor; Enterochromaffin Cells; Humans; Immunohistochemistry; Intestinal Neoplasms; Intestine, Small; Pentagastrin; Serotonin; Tumor Cells, Cultured; Vagus Nerve
PubMed: 8686805
DOI: 10.1016/S0002-9610(96)00078-5 -
Digestion 1994During recent years, the so-called ECL cells of the acid-producing part of the stomach have attracted much attention, mainly due to the fact that mice and rats were... (Review)
Review
During recent years, the so-called ECL cells of the acid-producing part of the stomach have attracted much attention, mainly due to the fact that mice and rats were found to develop gastric carcinoids (ECL cell tumors) following life-long treatment with blockers of acid secretion. These observations touched off concern about the safety of the long-term clinical use of such drugs. The ECL cells are the predominant endocrine cell population in the oxyntic mucosa. They produce histamine, chromogranin A/pancreastatin and an as yet unidentified peptide hormone. They respond to gastrin by the release of secretory products; more long-term responses include adaptation to the gastrin stimulus, hypertrophy and hyperplasia. Intravenous infusion of maximally effective doses of gastrin promptly reduced the number of cytoplasmic vesicles in the ECL cells and their content of histamine and pancreastatin. Despite the ongoing infusion of gastrin, the number of vesicles and the content of histamine and pancreastatin were back to normal 4-6 h after the start of the infusion. The histidine decarboxylase (HDC) activity and HDC mRNA level increased progressively until plateaus were reached after 6-8 h of gastrin infusion. The size of the ECL cells started to increase about 4 days after the start of a subcutaneous gastrin infusion (resulting in half-maximally effective serum gastrin concentrations). The ECL cell size reached maximum after about 2 weeks and then remained at this level.The number of cytoplasmic vesicles was increased; this effect seemed to reach a maximum after 1-2 weeks.(ABSTRACT TRUNCATED AT 250 WORDS)
Topics: Animals; Chromogranin A; Chromogranins; Cytoplasmic Granules; Enterochromaffin Cells; Gastric Mucosa; Gastrins; Histamine; Histidine Decarboxylase; Humans; Mice; Pancreatic Hormones; Rats
PubMed: 7698536
DOI: 10.1159/000201200 -
Current Opinion in Endocrinology,... Apr 2022To shed light on the recently uncovered diverse role of serotonin (5-hydroxytryptamine; 5-HT) in the regulation of immune functions, inflammation, metabolism, and... (Review)
Review
PURPOSE OF REVIEW
To shed light on the recently uncovered diverse role of serotonin (5-hydroxytryptamine; 5-HT) in the regulation of immune functions, inflammation, metabolism, and gut-brain axis.
RECENT FINDINGS
Peripheral 5-HT which accounts for approximately 95% of the total is largely synthesized in the gut by enterochromaffin cells. Enterochromaffin cells release 5-HT in response to various stimuli including microbial products. Released 5-HT influences secretomotor, sensory and immune functions as well as inflammatory processes in the gut. 5-HT released from enterochromaffin cells enters circulation and is taken up and concentrated in platelets. 5-HT released from the activated platelets interacts with different organs to alter their metabolic activity. 5-HT also serves as a link in the gut-brain axis.
SUMMARY
Emerging evidence regarding the role of peripheral 5-HT in the regulation of various physiological and pathophysiological conditions opens up new targets for researchers to explore and for clinicians to treat and manage different diseases associated with the altered 5-HT signalling.
Topics: Brain-Gut Axis; Enterochromaffin Cells; Humans; Immunity; Inflammation; Serotonin
PubMed: 35197425
DOI: 10.1097/MED.0000000000000713 -
Digestive Diseases and Sciences Feb 1991Gastric enterochromaffin-like cell carcinoids have been detected in rats exposed lifelong to omeprazole. By inhibiting acid secretion, omeprazole causes hypergastrinemia... (Review)
Review
Gastric enterochromaffin-like cell carcinoids have been detected in rats exposed lifelong to omeprazole. By inhibiting acid secretion, omeprazole causes hypergastrinemia which, with prolonged exposure, exerts a trophic effect on enterochromaffin-like cells with eventual enterochromaffin-like cell carcinoid formation in some animals. This mechanism seems to explain the appearance of enterochromaffin-like cell carcinoids in human hypergastrinemic states, whether associated with hyperchlorhydria, eg, Zollinger-Ellison syndrome, or with hypochlorhydria, eg, pernicious anemia (nonantral atrophic gastritis). Omeprazole produces modest serum gastrin elevations in humans when monitored over a 24-hr period. Gastrin levels are markedly lower and less sustained than in the above hypergastrinemic states. Extensive gastric biopsy data from patients enrolled in long-term studies indicate that omeprazole administration is not associated with clinically significant changes in the human oxyntic endocrine cell population. Man and rat differ markedly both in their gastrin response to a given level of acid inhibition and in their response to the trophic influence of gastrin on enterochromaffin-like cells. The rat model is a false indicator of risk in man.
Topics: Cell Count; Enterochromaffin Cells; Gastrins; Humans; Omeprazole
PubMed: 1988254
DOI: 10.1007/BF01300745 -
Behavioural Brain Research 1996Large amounts of 5-HT are present in the mammalian intestine where the amine is concentrated in the enterochromaffin cells (ECs) of the mucosa. ECs have the enzymes to... (Review)
Review
Large amounts of 5-HT are present in the mammalian intestine where the amine is concentrated in the enterochromaffin cells (ECs) of the mucosa. ECs have the enzymes to synthesize 5-HT, are endowed with a specific, imipramine-sensitive 5-HT uptake mechanism and can store 5-HT in specific secretory vesicles. ECs can secrete 5-HT in a calcium-dependent manner. In particular, calcium influx through voltage-regulated channels and receptor-mediated liberation of intracellular calcium can evoke 5-HT release. 5-HT secretion from ECs occurs predominantly at the interstitial side and is controlled by a complex pattern of receptor-mediated mechanisms. Stimulatory receptors (beta-adrenoceptors, muscarine, nicotine and 5-HT3 receptors) and inhibitory receptors (alpha 2-adrenoceptors, histamine H3, GABAA- and GABAB-, A2 and P2y alpha purine and 5-HT4 receptors as well as receptors for vasoactive intestinal polypeptide (VIP), pituitary adenylate cyclase stimulating peptide (PACAP) and somatostatin) have been shown to be involved in the control of 5-HT release from the ECs.
Topics: Animals; Enterochromaffin Cells; Humans; Receptors, Serotonin; Serotonin
PubMed: 8788482
DOI: 10.1016/0166-4328(96)00075-7 -
Analytical Chemistry Sep 2020Enteroendocrine (EE) cells within the intestinal epithelium produce a range of hormones that have key roles in modulating satiety and feeding behavior in humans. The...
Enteroendocrine (EE) cells within the intestinal epithelium produce a range of hormones that have key roles in modulating satiety and feeding behavior in humans. The regulation of hormone release from EE cells as a potential therapeutic strategy to treat metabolic disorders is highly sought after by the pharmaceutical industry. However, functional studies are limited by the scarcity of EE cells (or surrogates) in both and systems. Enterochromaffin (EC) cells are a subtype of EE cells that produce serotonin (5HT). Here, we explored simple strategies to enrich EC cells in monolayer systems derived from human primary intestinal stem cells. During differentiation of the monolayers, the EC cell lineage was significantly altered by both the culture method [air-liquid interface (ALI) submerged] and the presence of vasoactive intestinal peptide (VIP). Compared with traditional submerged cultures without VIP, VIP-assisted ALI culture significantly boosted the number of EC cells and their 5HT secretion by up to 430 and 390%, respectively. The method also increased the numbers of other subtypes of EE cells such as L cells. Additionally, this method generated monolayers with enhanced barrier integrity, so that directional (basal or apical) 5HT secretion was measurable. For all donor tissues, the enriched EC cells improved the signal-to-background ratio and reliability of 5HT release assays. The enhancement in the 5HT secretion behavior was consistent over time from a single donor, but significant variation in the amount of secreted 5HT was present among tissues derived from five different donors. To demonstrate the utility of the EC-enriched monolayer system, 13 types of pungent food ingredients were screened for their ability to stimulate 5HT secretion. Curcumin found in the spice turmeric derived from the plant was found to be the most potent secretagogue. This EC-enriched cell monolayer platform can provide a valuable analytical tool for the high-throughput screening of nutrients and gut microbial components that alter the secretion of 5HT.
Topics: Enterochromaffin Cells; Humans; Intestinal Mucosa; Serotonin
PubMed: 32819098
DOI: 10.1021/acs.analchem.0c02016 -
Pediatrics Jan 1961
Topics: Appendix; Carcinoid Tumor; Child; Enterochromaffin Cells; Humans; Infant; Neoplasms
PubMed: 13730299
DOI: No ID Found -
Neuro Endocrinology Letters Apr 2002Melatonin, a pineal hormone, because of its wide activity spectrum, is a subject of much current interest for biologists and physicians. It has been demonstrated that... (Review)
Review
Melatonin, a pineal hormone, because of its wide activity spectrum, is a subject of much current interest for biologists and physicians. It has been demonstrated that pineal gland is not an exclusive source of melatonin synthesis. Melatonin synthesis has been found in different sites of the organism, and a major source of extrapineal melatonin is the gastrointestinal tract. The role of melatonin in gastrointestinal functions is considered in the present review.
Topics: Animals; Digestive System; Digestive System Physiological Phenomena; Enterochromaffin Cells; Humans; Melatonin
PubMed: 12011798
DOI: No ID Found