• Molecules and Cells
• /
• v.39 no.4
• /
• pp.358-366
• /
• 2016

The digestive system is gaining interest as a major regulator of various functions including immune defense, nutrient accumulation, and regulation of feeding behavior, aside from its conventional function as a digestive organ. The Drosophila midgut epithelium is completely renewed every 1-2 weeks due to differentiation of pluripotent intestinal stem cells in the midgut. Intestinal stem cells constantly divide and differentiate into enterocytes that secrete digestive enzymes and absorb nutrients, or enteroendocrine cells that secrete regulatory peptides. Regulatory peptides have important roles in development and metabolism, but study has mainly focused on expression and functions in the nervous system, and not much is known about the roles in endocrine functions of enteroendocrine cells. We systemically examined the expression of 45 regulatory peptide genes in the Drosophila midgut, and verified that at least 10 genes are expressed in the midgut enteroendocrine cells through RT-PCR, in situ hybridization, antisera, and 25 regulatory peptide-GAL transgenes. The Drosophila midgut is highly compartmentalized, and individual peptides in enteroendocrine cells were observed to express in specific regions of the midgut. We also confirmed that some peptides expressed in the same region of the midgut are expressed in mutually exclusive enteroendocrine cells. These results indicate that the midgut enteroendocrine cells are functionally differentiated into different subgroups. Through this study, we have established a basis to study regulatory peptide functions in enteroendocrine cells as well as the complex organization of enteroendocrine cells in the Drosophila midgut.

• Journal of Life Science
• /
• v.8 no.6
• /
• pp.660-666
• /
• 1998

The effect of paraquat(1,1´-dimethyl-4,4'-bipyridinium) on the gastrin-, somatostatin-, glucagon-, PP-, CCK-8- and serotonin-immunoreactive cells in the stomach and small intestine of developing rat was examined by peroxidase-an-tiperoxidase method. Oral administration of this herbicide(9mg/Kg per day in 0.2ml of D.W) on days 7 to 14 of gestation revealed some difference, such as first appearance and distribution pattern of immunoreactive cells between control and paraquat-treated group. These results suggest that indirectly treated fetuses display a general developmental retardation on enteroendocrine cells differentiation as well as on gastrointestinal maturation

• Biomolecules & Therapeutics
• /
• v.21 no.2
• /
• pp.121-125
• /
• 2013

Hesperetin (3',5,7-trihydroxy 4'-methoxyflavanone) and its glycoside hesperidin (hesperetin 7-rhamnoglucoside) in oranges have been reported to possess pharmacological effects related to anti-obesity. However, hesperetin and hesperidin have not been studied on suppressive effects on appetite. This study examined that hesperetin and hesperidin can stimulate the release of cholecystokinin (CCK), one of appetite-regulating hormones, from the enteroendocrine STC-1 cells, and then examined the mechanisms involved in the CCK release. Hesperetin significantly and dose-dependently stimulated CCK secretion with an $EC_{50}$ of 0.050 mM and increased the intracellular $Ca^{2+}$ concentrations ($[Ca^{2+}]_i$) compared to the untreated control. The stimulatory effect by hesperetin was mediated via the entry of extracellular $Ca^{2+}$ and the activation of TRP channels including TRPA1. These results suggest that hesperetin can be a candidate biomolecule for the suppression of appetite and eventually for the therapeutics of obesity.

• The Korean Journal of Zoology
• /
• v.33 no.3
• /
• pp.276-296
• /
• 1990

This study attempts to investigate several enteroendocrine cells in the gastrointestinal epithelia of the Korean snakes (Dinodon rufozonatum rufozonotum Rhabdophis tigrina tigrina, Enhydris rufodorsata, Agkistrodon blomhoffii brevicaudus, Agkistrodon saxatilis, Agkistodon calginosus). For a light-microscopical examination of immunocytochemistry, the paraffin sections (5 $\mu$ m) of tissue specimens taken from the various parts of the gastrointestinal tract were stained immunocytochemically by PAP procedure with 10 antisera. The frequency of enteroendocrine cells per unit area (mm$^2$) of each mucosa were counted and the shapes of the cells were observed. In Dinodon rufozonatum rufozonatum, Rhobdophis tigrina tigrina, Enhydris rufodorsata, Agkistrodon saxatilis and Agkistrodon caliginosus, cholecystokinin (CCK)-8, gastrin, pancreatic polypeptide (PP) and serotonin cells were observed. But the freuqency of these immunoreactive cells differ trom each portion of gastrointestinal tracts of all species, respectively. In Agkistrodon blomhoffii brevicaudus, CCK-8, gastrin and serotonin cells were observed. CCK-8 and serotonin cells were found in whole gastrointestinal tracts and gastrin cells were observed in pylorus and mucosa of small intestine. The frequency of these cells was different from each portion. The shapes of CCK-8, gastrin, PP and serotonin cells were pyramidal or oval and closed type in stomach. A large number of these cells were spindle in shape and open type in small intestine and anterior pant of large intestine, whereas some cells were closed type. In posterior part of large intestine and rectum, these cells were oval in shape and closed type.

• Journal of Physiology & Pathology in Korean Medicine
• /
• v.26 no.4
• /
• pp.497-505
• /
• 2012

To determine the effects of Banggihwanggi-tang(BGHGT) on obesity, the obesity-related factors[gastrin, calcitonin gene related peptide(CGRP), serotonin, ghrelin, obestatin, glucagon-like peptide-1(GLP-1), insulin, orexin, leptin] were investigated in the stomach, pancreas, brain of mice by immunohistochemical(IHC) methods for 4 weeks. The change of body weight was more reduced in BGHGT administered group than that of control group. The IHC density of the gastrin and CGRP positive cells on pylorus was higher in BGHGT administered group than that of control group. The number of ghrelin immunoreactive cells on stomach was lower in BGHGT administered group than that of control group. The IHC of GLP-1 positive cells did not observe in the stomach of BGHGT administered groups. The IHC density of GLP-1 in the pancreas was lower in BGHGT administered group than that of control group. The IHC density of insulin positive cells in the pancreas was lower in BGHGT administered group than that of control group. The IHC density of orexin positive neurons in the diencephalon was slightly higher in BGHGT administered group than that of control group. The IHC density of NPY and leptin positive neurons was slightly higher in BGHGT administered group than that of control group. The IHC density of serotonin positive neurons was higher in BGHGT administered group than that of control group. Therefore, we conclude that BGHGT activates appetite inhibitor through appetite related enteroendocrine cells and neuropeptides in stomach, pancreas and brain, and this activation may also be responsible for the inhibition of feeding behavior.

• Nutrition Research and Practice
• /
• v.8 no.2
• /
• pp.146-150
• /
• 2014

BACKGROUND/OBJECTIVES: Cholecystokinin (CCK), a hormone or neuropeptide, is secreted in response to intraluminal nutrients by enteroendocrine I-cells of the intestine and has important physiological actions related to appetite regulation and satiety. The stimulation on CCK secretion from the intestine is of potential relevance for body weight management. Naringenin (4',5,7-trihydroxyflavanone) and its glycoside naringin (naringenin 7-rhamnoglucoside) have been reported to have many biological functions. In the current study, we investigated the question of whether naringenin and naringin could stimulate CCK secretion and then examined the mechanisms involved in CCK release. MATERIALS/METHODS: STC-1 cells were used as a model of enteroendocrine cells. CCK release and changes in intracellular $Ca^{2+}$ ($[Ca^{2+}]_i$) were measured after incubation of cells with naringenin and naringin for 1 h. RESULTS: Naringenin caused significant (P < 0.05) stimulation of CCK secretion, but naringin did not. In addition, regarding the secretory mechanisms, naringenin-induced CCK secretion involved increases in $[Ca^{2+}]_i$, influx of extracellular $Ca^{2+}$, at least in part, and activation of TRP channels, including TRPA1. CONCLUSION: Findings of this study suggest that naringenin could have a role in appetite regulation and satiety.

• Applied Microscopy
• /
• v.17 no.1
• /
• pp.83-97
• /
• 1987

In order to discriminate the enteroendocrine cell types in the mucosal epithelium of the normal duodenum of the Korean hedgehog (Erinaceus koreanus). The tissues were fixed in the mixture of 1% paraformaldehyde and 1% glutaraldehyde in phosphate buffer (pH 7.2), and postfixed in 2% osmium tetroxide (phosphate buffer, pH 7.2). They were embedded in Araldite, and the ultrathin sections were made by LKB-V ultratome following the inspection of semithin sections stained with toluidine blue-borax solutions. Ultrathin sections contrasted with uranyl acetate and lead citrate were observed with JEM 100B electron microscope. At least six types of enteroendocrine cells distributed in the mucosal epithelium of the duodenum were identified according to their morphological characteristics mainly based on the size, shape, number and electron density of the secretory granules. Type I cells had moderately developed organelles. The secretory granules were pleomorphic ($370X510nm$), and the granule cores with high electron density were enveloped in limiting membrane and characterized by a narrow halo. Type II cells contained an indented nucleus and well-developed organelles. The secretory granules were round (350 nm) and classified in two kinds by electron density, moderate and high. Both granules were surrounded by limiting membrane and those with high electron density showed often a wide halo. Type III cells had an indented nucleus. The secretory granules with various electron density were round (220 nm) in shape. The granules with high electron density were enveloped in limiting membrane and characterized by a narrow halo, but those with low or moderate electron density had not been observed the limiting membrane. Type IV cells contained an indented nucleus and moderately developed organelles. The secretory granules were round (180 nm) in shape, and the granule cores with high electron density were enveloped in limiting membrane and showed often a wide halo. Type V cells had a large amount of rough endoplasmic reticulum. Secretory granules with low or moderate electron density were round (230 nm) in shape, and surrounded by limiting membrane and showed a narrow halo. Type VI cells contained an oval nucleus and well-developed organelles, especially Golgi complex. The secretory granules with high electron density were round (210 nm) in shape. The granules were enveloped in limiting membrane and showed often a wide halo.

• Proceedings of the Zoological Society Korea Conference
• /
• 1996.10a
• /
• pp.133.1-133
• /
• 1996

No Abstract, See Full Text

• Journal of Life Science
• /
• v.9 no.2
• /
• pp.24-33
• /
• 1999

The gastrointestinal tract of three Percida, Lateolabrax japonicus, Epinephelus septemfasciatus and Mugil cephalus, was investigated immunocytochemically for the occurrence of somatostatin-. seotonin-, gastrin-, pancreatic polypeptide(PP)-, cholecystokinin-8(CCK-8)- and glucagon-immunoreactive cells. In Lateolabrax japonicus and Epinephelus septemfasciatus, five endorcrine cell types, such as somatostatin-, serotonin-, gastrin-, PP- and CCk-8-immunoreactive cells were demonstrated. In Mugil cephalus, however, six endocrine cell types, such as somatostatin-, serotnin-gastrin-, PP-, CCK-8- and glucagon-immunoreactive cells were detected. Somatostatin- and serotonin-immunoreactive cells were detected in the gastric mucosa of all species. Glucagon-immunoreactive cells were found only in the gastric mucoas of Mugil cephalus. In the pyloric caeca, PP-and CCK-8-immnuoreactive cells fo all species. gastrin-immunoreactive cells of Epinephelus septemfasciatus and Mugil cephalus, and serotonin-immunoreactive cells of Epinephelus septemfasciatus were demonstrated. In the intestinal mucosa of all species, gastrin-, PP- and CCK-8-immunoreactive cells were detected, and in the intestinal mucosa of Epinephelus septemfasciatus serotonin-immunoreactive cells were also detected. The frequency of these immunoreactive cells differs from each portion of the gastrointestinal tract of all species.

• The Korean Journal of Zoology
• /
• v.30 no.2
• /
• pp.154-166
• /
• 1987

Recently, the researches on the enteroendocrine cells of vertebrates have made a remarkable advance by the immunocytochemical methods. This study was attempted to investigate the topographical distributions and the shapes of gastrin, glucagon, somatostatin and cholecystokinin-8 immuno-reactive cells in the gastrointestinal tract of the Korean hedgehog, Erinaceus koreanus. For light-microscopical examination of immunocytochemistry, the tissue specimens taken from the various portions(body and pyloric protion of stomach, duodenum, jejunum, ileum and rectum) were fixed in glutaraldehyde-picric acid-acetic acid (GPA) or 10% neutral buffered formalin solutions. For the demonstration of immunoreactive cells, the paraffin sections (6$\mu$m) were immunocytochemically identified by PAP procedure (Sternberger, 1979) with gastrin, glucagon, somatostatin and cholecystokinin-8 antisera. Gastrin-immunoreactive cells were mainly distributed in the pyloric portion of stomach and were a few in the duodenum and jejunum. The shapes of these cells were round or oval in the pyloric portion and pyramidal in the small intestine. Glucagon-immunoreactive cells were sparsely distributed in the only small intestine. The shapes of these cells were mainly pyramidal. Somatostatin-immunoreactive cells were a few in the pyloric portion and duodenum, and were sparsely distributed in the body of stomach and jejunum. The shapes of these cells were round or oval in the stomach and oval or pyramidal in the small intestine. Cholecystokinin-8-immunoreactive cells were sparsely distributed in the only small intestine. The shapes of these cells were mainly oval or pyramidal.