Transport mechanism of lipid covered saquinavir pure drug nanoparticles in intestinal epithelium

DEFF Research Database (Denmark)

Xia, Dengning; He, Yuan; Li, Qiuxia

2018-01-01

are transported. To improve cellular uptake and transport of pure nanodrug in cells, here, a lipid covered saquinavir (SQV) pure drug NP (Lipo@nanodrug) was designed by modifying a pure SQV NP (nanodrug) with a phospholipid bilayer. We studied their endocytosis, intracellular trafficking mechanism using Caco-2...... their intracellular processing, helping to improve drug transport across intestinal epithelium. To our knowledge, this is the first presentation of the novel phospholipid bilayer covered SQV pure drug NP design, and a mechanistic study on intracellular trafficking in in vitro cell models has been described......Pure drug nanoparticles (NPs) represent a promising formulation for improved drug solubility and controlled dissolution velocity. However, limited absorption by the intestinal epithelium remains challenge to their clinical application, and little is known about how these NPs within the cells...

Microbiota promote secretory cell determination in the intestinal epithelium by modulating host Notch signaling.

Science.gov (United States)

Troll, Joshua V; Hamilton, M Kristina; Abel, Melissa L; Ganz, Julia; Bates, Jennifer M; Stephens, W Zac; Melancon, Ellie; van der Vaart, Michiel; Meijer, Annemarie H; Distel, Martin; Eisen, Judith S; Guillemin, Karen

2018-02-23

Resident microbes promote many aspects of host development, although the mechanisms by which microbiota influence host tissues remain unclear. We showed previously that the microbiota is required for allocation of appropriate numbers of secretory cells in the zebrafish intestinal epithelium. Because Notch signaling is crucial for secretory fate determination, we conducted epistasis experiments to establish whether the microbiota modulates host Notch signaling. We also investigated whether innate immune signaling transduces microbiota cues via the Myd88 adaptor protein. We provide the first evidence that microbiota-induced, Myd88-dependent signaling inhibits host Notch signaling in the intestinal epithelium, thereby promoting secretory cell fate determination. These results connect microbiota activity via innate immune signaling to the Notch pathway, which also plays crucial roles in intestinal homeostasis throughout life and when impaired can result in chronic inflammation and cancer. © 2018. Published by The Company of Biologists Ltd.

Innate immune signalling at the intestinal epithelium in homeostasis and disease

Science.gov (United States)

Pott, Johanna; Hornef, Mathias

2012-01-01

The intestinal epithelium—which constitutes the interface between the enteric microbiota and host tissues—actively contributes to the maintenance of mucosal homeostasis and defends against pathogenic microbes. The recognition of conserved microbial products by cytosolic or transmembrane pattern recognition receptors in epithelial cells initiates signal transduction and influences effector cell function. However, the signalling pathways, effector molecules and regulatory mechanisms involved are not yet fully understood, and the functional outcome is poorly defined. This review analyses the complex and dynamic role of intestinal epithelial innate immune recognition and signalling, on the basis of results in intestinal epithelial cell-specific transgene or gene-deficient animals. This approach identifies specific epithelial cell functions within the diverse cellular composition of the mucosal tissue, in the presence of the complex and dynamic gut microbiota. These insights have thus provided a more comprehensive understanding of the role of the intestinal epithelium in innate immunity during homeostasis and disease. PMID:22801555

Growth of intestinal epithelium in organ culture is dependent on EGF signalling

International Nuclear Information System (INIS)

Abud, Helen E.; Watson, Nadine; Heath, Joan K.

2005-01-01

Differentiation of endoderm into intestinal epithelium is initiated at E13.5 of mouse development when there are significant changes in morphology resulting in the conversion of undifferentiated stratified epithelium into a mature epithelial monolayer. Here we demonstrate that monolayer formation is associated with the selective apoptosis of superficial cells lining the lumen while cell proliferation is progressively restricted to cells adjacent to the basement membrane. We describe an innovative embryonic gut culture system that maintains the three-dimensional architecture of gut and in which these processes are recapitulated in vitro. Explants taken from specific regions of the gut and placed into organ culture develop and express molecular markers (Cdx1, Cdx2 and A33 antigen) in the same spatial and temporal pattern observed in vivo indicating that regional specification is maintained. Inhibition of the epidermal growth factor receptor (EGFR) tyrosine kinase using the specific inhibitor AG1478 significantly reduced the proliferation and survival of cells within the epithelial cell layer of cultured gut explants. This demonstrates an essential role for the EGF signalling pathway during the early stages of intestinal development

Mechanism for radiation-induced damage via TLR3 on the intestinal epithelium

International Nuclear Information System (INIS)

Takemura, Naoki; Uematsu, Satoshi

2014-01-01

When the small-intestinal epithelium is injured due to high-dose radiation exposure, radiation-induced gastrointestinal syndrome (GIS) such as absorption inhibition and intestinal bacterial infection occurs, and lead to subacute death. The authors immunologically analyzed the disease onset mechanism of GIS. In the small-intestinal mucosal epithelium, the intestinal epithelial stem cells of crypt structure and their daughter cells are renewed through proliferation and differentiation in the cycle of 3 or 4 days. When DNA is damaged by radiation, although p53 gene stops cell cycle and repairs DNA, cell death is induced if the repair is impossible. When stem cells perish, cell supply stops resulting in epithelial breakdown and fatal GIS. The authors analyzed the involvement in GIS of toll-like receptor (TLR) with the function of natural immunity, based on lethal γ-ray irradiation on KO mice and other methods. The authors found the mechanism, in which RNA that was leaked due to cell death caused by p53 gene elicits inflammation by activating TLR3, and leads to GIS through a wide range of cell death induction and stem cell extinction. The administration of a TLR3/RNA binding inhibitor before the irradiation of mice decreased crypt cell death and greatly improved survival rate. The administration one hour after the irradiation also showed improvement. The administration of the TLR3 specific inhibitor within a fixed time after the exposure is hopeful for the prevention of GIS, without affecting the DNA repair function of p53 gene. (A.O.)

Roles of the cytoskeleton and of Protein Phosphorylation Events in the Osmotic Stress Response in EEL Intestinal Epithelium

DEFF Research Database (Denmark)

Lionetto, Maria G; Pedersen, Stine F; Hoffmann, Else K

2002-01-01

The eel intestinal epithelium responds to an acute hypertonic challenge by a biphasic increase of the rate of Cl(-) absorption (measured as short circuit current, Isc, and creating a negative transepithelial potential, V(te), at the basolateral side of the epithelium). While the first, transient...... phase is bumetanide-insensitive, the second, sustained phase is bumetanide-sensitive, reflecting activation of the apically located Na(+)-K(+)-2Cl(-) (NKCC) cotransporter, which correlates with the cellular RVI response. Here, we investigated the involvement of the cytoskeleton and of serine....../threonine phosphorylation events in the osmotic stress-induced ion transport in the eel intestinal epithelium, focusing on the sustained RVI phase, as well as on the previously uncharacterized response to hypotonic stress. The study was carried out using confocal laser scanning microscopy, a quantitative F-actin assay...

Wnt control of stem cells and differentiation in the intestinal epithelium

International Nuclear Information System (INIS)

Pinto, Daniel; Clevers, Hans

2005-01-01

The intestinal epithelium represents a very attractive experimental model for the study of integrated key cellular processes such as proliferation and differentiation. The tissue is subjected to a rapid and perpetual self-renewal along the crypt-villus axis. Renewal requires division of multipotent stem cells, still to be morphologically identified and isolated, followed by transit amplification, and differentiation of daughter cells into specialized absorptive and secretory cells. Our understanding of the crucial role played by the Wnt/β-catenin signaling pathway in controlling the fine balance between cell proliferation and differentiation in the gut has been significantly enhanced in recent years. Mutations in some of its components irreversibly lead to carcinogenesis in humans and in mice. Here, we discuss recent advances related to the Wnt/β-catenin signaling pathway in regulating intestinal stem cells, homeostasis, and cancer. We emphasize how Wnt signaling is able to maintain a stem cell/progenitor phenotype in normal intestinal crypts, and to impose a very similar phenotype onto colorectal adenomas

A breakdown in communication? Understanding the effects of aging on the human small intestine epithelium

OpenAIRE

Mabbott, Neil A.

2015-01-01

In the intestine, a single layer of epithelial cells sealed together at their apical surfaces by tight junctions helps to prevent the luminal commensal and pathogenic micro-organisms and their toxins from entering host tissues. The intestinal epithelium also helps to maintain homoeostasis in the mucosal immune system by expressing anti-inflammatory cytokines in the steady state and inflammatory cytokines in response to pathogens. Although the function of the mucosal immune system is impaired ...

Impact of lactic Acid bacteria on dendritic cells from allergic patients in an experimental model of intestinal epithelium.

Science.gov (United States)

Ratajczak, Céline; Duez, Catherine; Grangette, Corinne; Pochard, Pierre; Tonnel, André-Bernard; Pestel, Joël

2007-01-01

Lactic acid bacteria (LAB) are Gram positive nonpathogenic commensal organisms present in human gastrointestinal tract. In vivo, LAB are separated from antigen-presenting cells such as dendritic cells (DC) by the intestinal epithelial barrier. In this study, the impact of one LAB strain (Lactobacillus casei ATCC393) on human monocyte-derived DC from allergic and healthy donors was assessed by using a polarized epithelium model. Confocal and flow cytometer analyses showed that immature DC efficiently captured FITC-labelled L. casei through the epithelial layer. After interaction with L. casei, DC acquired a partial maturation status (i.e., CD86 and CD54 increase) and increased their interleukin (IL)-10 and IL-12 production. Interestingly, after activation by L. casei in the presence of experimental epithelium, DC from allergic patients instructed autologous naïve CD4(+) T cells to produce more interferon-gamma than without the epithelium. Thus by modulating human DC reactivity, LAB and intestinal epithelium might modify T cell immune response and regulate the development of allergic reaction.

Impact of Lactic Acid Bacteria on Dendritic Cells from Allergic Patients in an Experimental Model of Intestinal Epithelium

Directory of Open Access Journals (Sweden)

Céline Ratajczak

2007-01-01

Full Text Available Lactic acid bacteria (LAB are Gram positive nonpathogenic commensal organisms present in human gastrointestinal tract. In vivo, LAB are separated from antigen-presenting cells such as dendritic cells (DC by the intestinal epithelial barrier. In this study, the impact of one LAB strain (Lactobacillus casei ATCC393 on human monocyte-derived DC from allergic and healthy donors was assessed by using a polarized epithelium model. Confocal and flow cytometer analyses showed that immature DC efficiently captured FITC-labelled L. casei through the epithelial layer. After interaction with L. casei, DC acquired a partial maturation status (i.e., CD86 and CD54 increase and increased their interleukin (IL-10 and IL-12 production. Interestingly, after activation by L. casei in the presence of experimental epithelium, DC from allergic patients instructed autologous naïve CD4+ T cells to produce more interferon-γ than without the epithelium. Thus by modulating human DC reactivity, LAB and intestinal epithelium might modify T cell immune response and regulate the development of allergic reaction.

Protein tyrosine phosphatase SAP-1 protects against colitis through regulation of CEACAM20 in the intestinal epithelium.

Science.gov (United States)

Murata, Yoji; Kotani, Takenori; Supriatna, Yana; Kitamura, Yasuaki; Imada, Shinya; Kawahara, Kohichi; Nishio, Miki; Daniwijaya, Edwin Widyanto; Sadakata, Hisanobu; Kusakari, Shinya; Mori, Munemasa; Kanazawa, Yoshitake; Saito, Yasuyuki; Okawa, Katsuya; Takeda-Morishita, Mariko; Okazawa, Hideki; Ohnishi, Hiroshi; Azuma, Takeshi; Suzuki, Akira; Matozaki, Takashi

2015-08-04

Intestinal epithelial cells contribute to regulation of intestinal immunity in mammals, but the detailed molecular mechanisms of such regulation have remained largely unknown. Stomach-cancer-associated protein tyrosine phosphatase 1 (SAP-1, also known as PTPRH) is a receptor-type protein tyrosine phosphatase that is localized specifically at microvilli of the brush border in gastrointestinal epithelial cells. Here we show that SAP-1 ablation in interleukin (IL)-10-deficient mice, a model of inflammatory bowel disease, resulted in a marked increase in the severity of colitis in association with up-regulation of mRNAs for various cytokines and chemokines in the colon. Tyrosine phosphorylation of carcinoembryonic antigen-related cell adhesion molecule (CEACAM) 20, an intestinal microvillus-specific transmembrane protein of the Ig superfamily, was greatly increased in the intestinal epithelium of the SAP-1-deficient animals, suggesting that this protein is a substrate for SAP-1. Tyrosine phosphorylation of CEACAM20 by the protein tyrosine kinase c-Src and the consequent association of CEACAM20 with spleen tyrosine kinase (Syk) promoted the production of IL-8 in cultured cells through the activation of nuclear factor-κB (NF-κB). In addition, SAP-1 and CEACAM20 were found to form a complex through interaction of their ectodomains. SAP-1 and CEACAM20 thus constitute a regulatory system through which the intestinal epithelium contributes to intestinal immunity.

Erlotinib promotes endoplasmic reticulum stress-mediated injury in the intestinal epithelium

Energy Technology Data Exchange (ETDEWEB)

Fan, Lu; Hu, Lingna; Yang, Baofang; Fang, Xianying; Gao, Zhe; Li, Wanshuai; Sun, Yang; Shen, Yan; Wu, Xuefeng [State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, 22 Hankou Road, Nanjing 210093 (China); Shu, Yongqian [Department of Clinical Oncology, The First Affiliated Hospital of Nanjing Medical University, 140 Hanzhong Road, Nanjing 210029 (China); Gu, Yanhong, E-mail: guluer@163.com [Department of Clinical Oncology, The First Affiliated Hospital of Nanjing Medical University, 140 Hanzhong Road, Nanjing 210029 (China); Wu, Xudong, E-mail: xudongwu@nju.edu.cn [State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, 22 Hankou Road, Nanjing 210093 (China); Xu, Qiang, E-mail: molpharm@163.com [State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, 22 Hankou Road, Nanjing 210093 (China)

2014-07-01

Erlotinib, a popular drug for treating non-small cell lung cancer (NSCLC), causes diarrhea in approximately 55% of patients receiving this drug. In the present study, we found that erlotinib induced barrier dysfunction in rat small intestine epithelial cells (IEC-6) by increasing epithelial permeability and down-regulating E-cadherin. The mRNA levels of various pro-inflammatory cytokines (Il-6, Il-25 and Il-17f) were increased after erlotinib treatment in IEC-6 cells. Erlotinib concentration- and time-dependently induced apoptosis and endoplasmic reticulum (ER) stress in both IEC-6 and human colon epithelial cells (CCD 841 CoN). Intestinal epithelial injury was also observed in male C57BL/6J mice administrated with erlotinib. Knockdown of C/EBP homologous protein (CHOP) with small interference RNA partially reversed erlotinib-induced apoptosis, production of IL-6 and down-regulation of E-cadherin in cultured intestinal epithelial cells. In conclusion, erlotinib caused ER stress-mediated injury in the intestinal epithelium, contributing to its side effects of diarrhea in patients. - Highlights: • Erlotinib destroyed barrier integrity both in vitro and in vivo. • Erlotinib induced inflammation both in vitro and in vivo. • Erlotinib induced apoptosis both in vitro and in vivo. • ER stress contributed to erlotinib-induced barrier dysfunction.

Erlotinib promotes endoplasmic reticulum stress-mediated injury in the intestinal epithelium

International Nuclear Information System (INIS)

Fan, Lu; Hu, Lingna; Yang, Baofang; Fang, Xianying; Gao, Zhe; Li, Wanshuai; Sun, Yang; Shen, Yan; Wu, Xuefeng; Shu, Yongqian; Gu, Yanhong; Wu, Xudong; Xu, Qiang

2014-01-01

Erlotinib, a popular drug for treating non-small cell lung cancer (NSCLC), causes diarrhea in approximately 55% of patients receiving this drug. In the present study, we found that erlotinib induced barrier dysfunction in rat small intestine epithelial cells (IEC-6) by increasing epithelial permeability and down-regulating E-cadherin. The mRNA levels of various pro-inflammatory cytokines (Il-6, Il-25 and Il-17f) were increased after erlotinib treatment in IEC-6 cells. Erlotinib concentration- and time-dependently induced apoptosis and endoplasmic reticulum (ER) stress in both IEC-6 and human colon epithelial cells (CCD 841 CoN). Intestinal epithelial injury was also observed in male C57BL/6J mice administrated with erlotinib. Knockdown of C/EBP homologous protein (CHOP) with small interference RNA partially reversed erlotinib-induced apoptosis, production of IL-6 and down-regulation of E-cadherin in cultured intestinal epithelial cells. In conclusion, erlotinib caused ER stress-mediated injury in the intestinal epithelium, contributing to its side effects of diarrhea in patients. - Highlights: • Erlotinib destroyed barrier integrity both in vitro and in vivo. • Erlotinib induced inflammation both in vitro and in vivo. • Erlotinib induced apoptosis both in vitro and in vivo. • ER stress contributed to erlotinib-induced barrier dysfunction

Capsule impairs efficient adherence of Streptococcus agalactiae to intestinal epithelium in tilapias Oreochromis sp.

Science.gov (United States)

Barato, P; Martins, E R; Vasquez, G M; Ramirez, M; Melo-Cristino, J; Martínez, N; Iregui, C

2016-11-01

Streptococcosis caused by Streptococcus agalactiae is one of the most important diseases in the tilapia aquaculture industry. The role of the capsule of Streptococcus agalactiae in adherence to fish surfaces has not been evaluated and the mechanism of capsular regulation during adhesion has not been described. The aim of this study was to evaluate the role of the capsule of S. agalactiae during adhesion to intestinal epithelium of tilapia (Oreochromis sp.) in an ex vivo infection model. We show that the capsule impairs the adhesion of bacteria to host intestinal epithelium. Wild type (WT) strain SaTiBe08-18 (S. agalactiae recovered from tilapia) had reduced adhesion (P S. agalactiae to tilapia intestine and that the acidic milieu could regulate adherence of encapsulated strains. We found GlcNAc on the surface of adherent Δcps but not over the capsule in WT. This difference could be explained by the GlcNAc composition of Lancefield group B antigen and the peptidoglycan in GBS (Group B Streptococcus) and also may be related with better exposure of glycosylated adhesins in unencapsulated fish GBS. Understanding capsular regulation during adhesion of S. agalactiae may provide new leads to find a successful anti-adherence therapy to prevent streptococcosis in tilapia. Copyright © 2016 Elsevier Ltd. All rights reserved.

Histological studies on the regeneration of small-intestine epithelium of rats irradiated with sublethal doses of x rays

Energy Technology Data Exchange (ETDEWEB)

Lewicki, Z; Figurski, R; Sulikowska, A

1975-01-01

The dynamics of regeneration of small-intestine epithelium was studied in rats irradiated with x rays in sublethal doses of 550, 600, or 750 R. Sixty-two irradiated and 22 control animals were used in the experiment. They were killed 1, 2, 4, 6, 8, 14, and 25 days after the irradiation. Specimens of duodenum and jejunum were examined histologically, the sections being stained with H. E. and p.a.S. Already 1 and 2 days after irradiation the intestinal villi became shorter and deformed. The blood vessels were damaged, the enterocytes showed features of degeneration and vacuolization, the epithelium was detached by the exudate which accumulated in the strong. Irradiation markedly disturbed the regeneration of intestinal epithelium in the period from the 1st to the 6th day. Cytological calculations indicate tha on the 1st and 2nd days after irradiation the number of epithelial cells of the villi, and particularly of young cryptal ones, markedly dropped. On the 4th and 6th days increased proliferation of young cryptal cells considerably surpassed the physiological rate. The accompanying disturbances in differentiation consisted in a decreased acidophilic to basophilic cells ration and in retardation of maturation of goblet cells. The absolute number of goblet cells was increased, as well as their proportion to the number of enterocytes.

The glucagon-like peptide 2 receptor is expressed in enteric neurons and not in the epithelium of the intestine

DEFF Research Database (Denmark)

Pedersen, Jens; B. Pedersen, Nis; Brix, Sophie W.

2015-01-01

fibrillary acidic protein in these isolated tissue fractions was quantified with qRT-PCR. Expression of the Glp2r was confined to compartments containing enteric neurons and receptor expression was absent in the epithelium. Our findings provide evidence for the expression of the GLP-2R in intestinal...... compartments rich in enteric neurons and, importantly they exclude significant expression in the epithelium of rat jejunal mucosa....

Radiosensitivity of mice of different lines and age as determinated with reference to ''intestinal'' death and DNA repair in intestinal epithelium cells

International Nuclear Information System (INIS)

Konoplyannikova, O.A.; Sklobovskaya, M.V.; Konoplyannikov, A.G.; Saenko, A.S.

1982-01-01

A study was made of the influence of strain- and age-related differences on mouse mortality after irradiation with doses lying within the ''intest+nal'' dose range, and also damages to stem cells of intestinal epithelium and induction and repair of single-strand DNA breaks in intestinal epitherium cells. Mice of different lines and age vary in LDsub(50/4) and stem cell radiosensitivity. There are no differences in the sedimentation constants of DNA fragments in alkaline lysates of intestinal crypts of intact mice of different age. Radiosensitivity determined with reference to single-strand breaks induction in DNA is similar with different mo use groups. Repair of single-strand DNA breaks of eldery mice is slower than that of young animals

Segment-specific responses of intestinal epithelium transcriptome to in-feed antibiotics in pigs.

Science.gov (United States)

Yu, Kaifan; Mu, Chunlong; Yang, Yuxiang; Su, Yong; Zhu, Weiyun

2017-10-01

Despite widespread use of antibiotics for treatment of human diseases and promotion of growth of agricultural animals, our understanding of their effects on the host is still very limited. We used a model in which pigs were fed with or without a cocktail of antibiotics and found, based on the denaturing gradient gel electrophoresis (DGGE) patterns, that the fecal bacteria from the treatment and control animals were distinct. Furthermore, the total bacterial population in the feces tended to be decreased by the antibiotic treatment ( P = 0.07), and the counts of Lactobacillus and Clostridium XIVa were significantly reduced ( P epithelium, we assessed gene expression profiles of the jejunum and ileum and their response to antibiotic administration. The results indicate that in-feed antibiotics increased expression of genes involved in immune functions in both the jejunum and ileum, some of which were clustered in the coexpression network. Gene ontology terms of metabolic processes were altered predominantly in the jejunum but not in the ileum. Notably, antibiotics diminished intestinal segment-specific transcriptional changes, especially for genes associated with metabolic functions. This study reveals segment-specific responses of host intestinal epithelium to in-feed antibiotics, which can be a valuable resource for deciphering antibiotic-microbiota-host interactions. Copyright © 2017 the American Physiological Society.

Intestinal metabolism of PAH: in vitro demonstration and study of its impact on PAH transfer through the intestinal epithelium

International Nuclear Information System (INIS)

Cavret, Severine; Feidt, Cyril

2005-01-01

Food would seem to be one of the main ways of animal and human contamination with polycyclic aromatic hydrocarbons (PAHs). In vivo studies suggest a transfer in intestinal epithelium by diffusion, which appears extensively governed by the physicochemical properties of PAHs, particularly lipophilicity. However, other mechanisms, such as metabolism, are considered to intervene. Our work aimed at testing in vitro intestinal metabolism and defining its impact on transepithelial transport of PAHs. Caco-2 cells were cultivated on permeable filters and incubated with 14 C-labeled benzo[a]pyrene (BaP), pyrene (Pyr), and phenanthrene (Phe), which differ in their physicochemical properties. The results showed that the cells were able to metabolize the compounds. In basal media, Phe appeared to be the least hydroxylated molecule (45% after a 6-h exposure), followed by Pyr (65%) and finally BaP (96%). Inhibition of PAH metabolism showed a determinant effect on kinetics profiles. Transfer in the basal compartment of BaP, Pyr, and Phe radioactivities was, respectively, 26, 4, and 2 times lower with inhibitors, corroborating that intestinal metabolism of PAHs would have a positive impact on their transfer, an impact that increased with their lipophilicity. Furthermore, after a 6-h incubation, metabolites were also detected in apical medium. These findings suggested that intestinal metabolism might play a key role in intestinal barrier permeability and thus in the bioavailability of tested micropollutants

Radiosensitivity of mice of different lines and age as determinated with reference to ''intestinal'' death and DNA repair in intestinal epithelium cells

Energy Technology Data Exchange (ETDEWEB)

Konoplyannikova, O.A.; Sklobovskaya, M.V.; Konoplyannikov, A.G.; Saenko, A.S. (Akademiya Meditsinskikh Nauk SSSR, Obninsk. Nauchno-Issledovatel' skij Inst. Meditsinskoj Radiologii)

A study was made of the influence of strain- and age-related differences on mouse mortality after irradiation with doses lying within the ''intestinal'' dose range, and also damages to stem cells of intestinal epithelium and induction and repair of single-strand DNA breaks in intestinal epitherium cells. Mice of different lines and age vary in LDsub(50/4) and stem cell radiosensitivity. There are no differences in the sedimentation constants of DNA fragments in alkaline lysates of intestinal crypts of intact mice of different age. Radiosensitivity determined with reference to single-strand breaks induction in DNA is similar with different mouse groups. Repair of single-strand DNA breaks of elderly mice is slower than that of young animals.

Comparison of the effects of an ornithine decarboxylase inhibitor on the intestinal epithelium and on intestinal tumors.

Science.gov (United States)

Tutton, P J; Barkla, D H

1986-12-01

Ornithine decarboxylase (ODC) catalyzes the rate-limiting step in the synthesis of polyamines, it has a short half-life, and its synthesis is under hormonal control. Recently, insight into the role of ODC and thus into the physiology of polyamines has been gained by the use of an inhibitor of ODC, difluoromethylornithine (DFMO). In the present report cell proliferation was measured by a stathmokinetic method in the crypt epithelium of the jejunum and colon of normal rats and in dimethylhydrazine-induced colonic tumors. Growth of human colon tumor xenografts in immunosuppressed mice and mouse colon tumor isografts was also assessed. Cell proliferation in primary colonic tumors was substantially suppressed by a single dose of DFMO at 100 mg/kg whereas the normal crypt epithelium of the small and large intestine required two doses at 400 mg/kg to produce a similar magnitude of inhibition of cell proliferation. DFMO was also found to suppress cell proliferation in, and the growth of, the transplantable colon cancers. Because of the apparent selectivity of the antimitotic activity of DFMO towards tumors, ODC inhibitors may prove to be useful anticancer drugs.

The effect of PGE2, gastrin and CCK-8 on postirradiation recovery of small intestine epithelium

International Nuclear Information System (INIS)

Dziekiewicz, M.; Chomiczewski, K.; Jablonska, H.

1997-01-01

The role of some natural factors in the postirradiation recovery of intestinal epithelium is a very interesting and inscrutable problem. In our experiment the comparative effect of PGE 2 , Gastrin and CCK-8 fragment of Cholecystokinin on this problem has been investigated. Male Swiss PZH mice 8 weeks old were irradiated to the whole body with a dose of 5.5 Gy and to abdomen with a dose of 12 Gy of gamma rays. The first experimental group received PGE 2 before 30 min. irradiation, the second received Gastrin after irradiation during 5 days, the third was injected with CCK-8 after irradiation during 5 days too. Unirradiated and only irradiated animals served as control groups. Survival of 30 mice in every group was registered during 30 days after irradiation. The another part of animals in every group were killed between 1 and 12 days after irradiation. Changes in the body weight were registered. Using computer image analysis system , some histological slides were examined, adding the statistical analysis of results. The preliminary results suggest that all those factors are able to stimulate the postirradiation regeneration of small intestinal epithelium (author)

Interactions between bacteria and the gut mucosa: Do enteric neurotransmitters acting on the mucosal epithelium influence intestinal colonization or infection?

Science.gov (United States)

The intestinal epithelium is a critical barrier between the internal and external milieux of the mammalian host. Epithelial interactions between these two host environments have been shown to be modulated by several different, cross-communicating cell types residing in the gut mucosa. These include ...

Distinct ATOH1 and Neurog3 requirements define tuft cells as a new secretory cell type in the intestinal epithelium

NARCIS (Netherlands)

Gerbe, F.; van Es, J.H.; Makrini, L.; Brulin, B.; Mellitzer, G.; Robine, S.; Romagnolo, B.; Shroyer, N.F.; Bourgaux, J.F.; Pignodel, C.; Clevers, H.; Jay, P.

2011-01-01

The unique morphology of tuft cells was first revealed by electron microscopy analyses in several endoderm-derived epithelia. Here, we explore the relationship of these cells with the other cell types of the intestinal epithelium and describe the first marker signature allowing their unambiguous

Use of collagen gel as an alternative extracellular matrix for the in vitro and in vivo growth of murine small intestinal epithelium.

Science.gov (United States)

Jabaji, Ziyad; Sears, Connie M; Brinkley, Garrett J; Lei, Nan Ye; Joshi, Vaidehi S; Wang, Jiafang; Lewis, Michael; Stelzner, Matthias; Martín, Martín G; Dunn, James C Y

2013-12-01

Methods for the in vitro culture of primary small intestinal epithelium have improved greatly in recent years. A critical barrier for the translation of this methodology to the patient's bedside is the ability to grow intestinal stem cells using a well-defined extracellular matrix. Current methods rely on the use of Matrigel(™), a proprietary basement membrane-enriched extracellular matrix gel produced in mice that is not approved for clinical use. We demonstrate for the first time the capacity to support the long-term in vitro growth of murine intestinal epithelium in monoculture, using type I collagen. We further demonstrate successful in vivo engraftment of enteroids co-cultured with intestinal subepithelial myofibroblasts in collagen gel. Small intestinal crypts were isolated from 6 to 10 week old transgenic enhanced green fluorescent protein (eGFP+) mice and suspended within either Matrigel or collagen gel; cultures were supported using previously reported media and growth factors. After 1 week, cultures were either lysed for DNA or RNA extraction or were implanted subcutaneously in syngeneic host mice. Quantitative real-time polymerase chain reaction (qPCR) was performed to determine expansion of the transgenic eGFP-DNA and to determine the mRNA gene expression profile. Immunohistochemistry was performed on in vitro cultures and recovered in vivo explants. Small intestinal crypts reliably expanded to form enteroids in either Matrigel or collagen in both mono- and co-cultures as confirmed by microscopy and eGFP-DNA qPCR quantification. Collagen-based cultures yielded a distinct morphology with smooth enteroids and epithelial monolayer growth at the gel surface; both enteroid and monolayer cells demonstrated reactivity to Cdx2, E-cadherin, CD10, Periodic Acid-Schiff, and lysozyme. Collagen-based enteroids were successfully subcultured in vitro, whereas pure monolayer epithelial sheets did not survive passaging. Reverse transcriptase-polymerase chain reaction

Development of a serum-free co-culture of human intestinal epithelium cell-lines (Caco-2/HT29-5M21)

Science.gov (United States)

Nollevaux, Géraldine; Devillé, Christelle; El Moualij, Benaïssa; Zorzi, Willy; Deloyer, Patricia; Schneider, Yves-Jacques; Peulen, Olivier; Dandrifosse, Guy

2006-01-01

Background The absorptive and goblet cells are the main cellular types encountered in the intestine epithelium. The cell lineage Caco-2 is a model commonly used to reproduce the features of the bowel epithelium. However, there is a strong debate regarding the value of Caco-2 cell culture to mimick in vivo situation. Indeed, some authors report in Caco-2 a low paracellular permeability and an ease of access of highly diffusible small molecules to the microvilli, due to an almost complete lack of mucus. The HT29-5M21 intestinal cell lineage is a mucin-secreting cellular population. A co-culture system carried out in a serum-free medium and comprising both Caco-2 and HT29-5M21 cells was developed. The systematic use of a co-culture system requires the characterization of the monolayer under a given experimental procedure. Results In this study, we investigated the activity and localization of the alkaline phosphatase and the expression of IAP and MUC5AC genes to determine a correlation between these markers and the cellular composition of a differentiated monolayer obtained from a mixture of Caco-2 and HT29-5M21 cells. We observed that the culture conditions used (serum-free medium) did not change the phenotype of each cell type, and produced a reproducible model. The alkaline phosphatase expression characterizing Caco-2 cells was influenced by the presence of HT29-5M21 cells. Conclusion The culture formed by 75% Caco-2 and 25% HT29-5M21 produce a monolayer containing the two main cell types of human intestinal epithelium and characterized by a reduced permeability to macromolecules. PMID:16670004

Serosal Zn2+ inhibits 8-Br-cAMP stimulated chloride secretion in piglet small intestinal epithelium in vitro

DEFF Research Database (Denmark)

Carlson, Dorthe; Sehested, Jakob; Poulsen, Hanne Damgaard

2010-01-01

. Piglets (n = 24) were weaned at 28 days of age and allocated at two dietary treatments (ZnO0 and ZnO2500) and at 5-6 days after weaning the piglets were slaughtered and small intestinal epithelium from each piglet was mounted into 8 Ussing chambers. The effect of 23 μM serosal Zn2+ on 8-Br-cAMP (8...

Development of a serum-free co-culture of human intestinal epithelium cell-lines (Caco-2/HT29-5M21

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Schneider Yves-Jacques

2006-05-01

Full Text Available Abstract Background The absorptive and goblet cells are the main cellular types encountered in the intestine epithelium. The cell lineage Caco-2 is a model commonly used to reproduce the features of the bowel epithelium. However, there is a strong debate regarding the value of Caco-2 cell culture to mimick in vivo situation. Indeed, some authors report in Caco-2 a low paracellular permeability and an ease of access of highly diffusible small molecules to the microvilli, due to an almost complete lack of mucus. The HT29-5M21 intestinal cell lineage is a mucin-secreting cellular population. A co-culture system carried out in a serum-free medium and comprising both Caco-2 and HT29-5M21 cells was developed. The systematic use of a co-culture system requires the characterization of the monolayer under a given experimental procedure. Results In this study, we investigated the activity and localization of the alkaline phosphatase and the expression of IAP and MUC5AC genes to determine a correlation between these markers and the cellular composition of a differentiated monolayer obtained from a mixture of Caco-2 and HT29-5M21 cells. We observed that the culture conditions used (serum-free medium did not change the phenotype of each cell type, and produced a reproducible model. The alkaline phosphatase expression characterizing Caco-2 cells was influenced by the presence of HT29-5M21 cells. Conclusion The culture formed by 75% Caco-2 and 25% HT29-5M21 produce a monolayer containing the two main cell types of human intestinal epithelium and characterized by a reduced permeability to macromolecules.

Human Milk Hyaluronan Enhances Innate Defense of the Intestinal Epithelium*

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Hill, David R.; Rho, Hyunjin K.; Kessler, Sean P.; Amin, Ripal; Homer, Craig R.; McDonald, Christine; Cowman, Mary K.; de la Motte, Carol A.

2013-01-01

Breast-feeding is associated with enhanced protection from gastrointestinal disease in infants, mediated in part by an array of bioactive glycan components in milk that act through molecular mechanisms to inhibit enteric pathogen infection. Human milk contains hyaluronan (HA), a glycosaminoglycan polymer found in virtually all mammalian tissues. We have shown that synthetic HA of a specific size range promotes expression of antimicrobial peptides in intestinal epithelium. We hypothesize that hyaluronan from human milk also enhances innate antimicrobial defense. Here we define the concentration of HA in human milk during the first 6 months postpartum. Importantly, HA isolated from milk has a biological function. Treatment of HT-29 colonic epithelial cells with human milk HA at physiologic concentrations results in time- and dose-dependent induction of the antimicrobial peptide human β-defensin 2 and is abrogated by digestion of milk HA with a specific hyaluronidase. Milk HA induction of human β-defensin 2 expression is also reduced in the presence of a CD44-blocking antibody and is associated with a specific increase in ERK1/2 phosphorylation, suggesting a role for the HA receptor CD44. Furthermore, oral administration of human milk-derived HA to adult, wild-type mice results in induction of the murine Hβ D2 ortholog in intestinal mucosa and is dependent upon both TLR4 and CD44 in vivo. Finally, treatment of cultured colonic epithelial cells with human milk HA enhances resistance to infection by the enteric pathogen Salmonella typhimurium. Together, our observations suggest that maternally provided HA stimulates protective antimicrobial defense in the newborn. PMID:23950179

Multi-level interactions between the nuclear receptor TRα1 and the WNT effectors β-catenin/Tcf4 in the intestinal epithelium.

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Maria Sirakov

Full Text Available Intestinal homeostasis results from complex cross-regulation of signaling pathways; their alteration induces intestinal tumorigenesis. Previously, we found that the thyroid hormone nuclear receptor TRα1 activates and synergizes with the WNT pathway, inducing crypt cell proliferation and promoting tumorigenesis. Here, we investigated the mechanisms and implications of the cross-regulation between these two pathways in gut tumorigenesis in vivo and in vitro. We analyzed TRα1 and WNT target gene expression in healthy mucosae and tumors from mice overexpressing TRα1 in the intestinal epithelium in a WNT-activated genetic background (vil-TRα1/Apc mice. Interestingly, increased levels of β-catenin/Tcf4 complex in tumors from vil-TRα1/Apc mice blocked TRα1 transcriptional activity. This observation was confirmed in Caco2 cells, in which TRα1 functionality on a luciferase reporter-assay was reduced by the overexpression of β-catenin/Tcf4. Moreover, TRα1 physically interacted with β-catenin/Tcf4 in the nuclei of these cells. Using molecular approaches, we demonstrated that the binding of TRα1 to its DNA target sequences within the tumors was impaired, while it was newly recruited to WNT target genes. In conclusion, our observations strongly suggest that increased β-catenin/Tcf4 levels i correlated with reduced TRα1 transcriptional activity on its target genes and, ii were likely responsible for the shift of TRα1 binding on WNT targets. Together, these data suggest a novel mechanism for the tumor-promoting activity of the TRα1 nuclear receptor.

Functional nanoparticles exploit the bile acid pathway to overcome multiple barriers of the intestinal epithelium for oral insulin delivery

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Fan, Weiwei; Xia, Dengning; Zhu, Quanlei

2018-01-01

, especially to avoid lysosomal degradation, and basolateral release. Here, the functional material, deoxycholic acid-conjugated chitosan, is synthesized and loaded with the model protein drug insulin into deoxycholic acid-modified nanoparticles (DNPs). The DNPs designed in this study are demonstrated......Oral absorption of protein/peptide-loaded nanoparticles is often limited by multiple barriers of the intestinal epithelium. In addition to mucus translocation and apical endocytosis, highly efficient transepithelial absorption of nanoparticles requires successful intracellular trafficking...... to endolysosomal escape of DNPs. Additionally, DNPs can interact with a cytosolic ileal bile acid-binding protein that facilitates the intracellular trafficking and basolateral release of insulin. In rats, intravital two-photon microscopy also reveals that the transport of DNPs into the intestinal villi...

GATA4 Is Sufficient to Establish Jejunal Versus Ileal Identity in the Small IntestineSummary

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Cayla A. Thompson

2017-05-01

Full Text Available Background & Aims: Patterning of the small intestinal epithelium along its cephalocaudal axis establishes three functionally distinct regions: duodenum, jejunum, and ileum. Efficient nutrient assimilation and growth depend on the proper spatial patterning of specialized digestive and absorptive functions performed by duodenal, jejunal, and ileal enterocytes. When enterocyte function is disrupted by disease or injury, intestinal failure can occur. One approach to alleviate intestinal failure would be to restore lost enterocyte functions. The molecular mechanisms determining regionally defined enterocyte functions, however, are poorly delineated. We previously showed that GATA binding protein 4 (GATA4 is essential to define jejunal enterocytes. The goal of this study was to test the hypothesis that GATA4 is sufficient to confer jejunal identity within the intestinal epithelium. Methods: To test this hypothesis, we generated a novel Gata4 conditional knock-in mouse line and expressed GATA4 in the ileum, where it is absent. Results: We found that GATA4-expressing ileum lost ileal identity. The global gene expression profile of GATA4-expressing ileal epithelium aligned more closely with jejunum and duodenum rather than ileum. Focusing on jejunal vs ileal identity, we defined sets of jejunal and ileal genes likely to be regulated directly by GATA4 to suppress ileal identity and promote jejunal identity. Furthermore, our study implicates GATA4 as a transcriptional repressor of fibroblast growth factor 15 (Fgf15, which encodes an enterokine that has been implicated in an increasing number of human diseases. Conclusions: Overall, this study refines our understanding of an important GATA4-dependent molecular mechanism to pattern the intestinal epithelium along its cephalocaudal axis by elaborating on GATA4’s function as a crucial dominant molecular determinant of jejunal enterocyte identity. Microarray data from this study have been deposited into

Paneth cells, antimicrobial peptides and maintenance of intestinal homeostasis.

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Bevins, Charles L; Salzman, Nita H

2011-05-01

Building and maintaining a homeostatic relationship between a host and its colonizing microbiota entails ongoing complex interactions between the host and the microorganisms. The mucosal immune system, including epithelial cells, plays an essential part in negotiating this equilibrium. Paneth cells (specialized cells in the epithelium of the small intestine) are an important source of antimicrobial peptides in the intestine. These cells have become the focus of investigations that explore the mechanisms of host-microorganism homeostasis in the small intestine and its collapse in the processes of infection and chronic inflammation. In this Review, we provide an overview of the intestinal microbiota and describe the cell biology of Paneth cells, emphasizing the composition of their secretions and the roles of these cells in intestinal host defence and homeostasis. We also highlight the implications of Paneth cell dysfunction in susceptibility to chronic inflammatory bowel disease.

Cytokine Tuning of Intestinal Epithelial Function

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Caroline Andrews

2018-06-01

Full Text Available The intestine serves as both our largest single barrier to the external environment and the host of more immune cells than any other location in our bodies. Separating these potential combatants is a single layer of dynamic epithelium composed of heterogeneous epithelial subtypes, each uniquely adapted to carry out a subset of the intestine’s diverse functions. In addition to its obvious role in digestion, the intestinal epithelium is responsible for a wide array of critical tasks, including maintaining barrier integrity, preventing invasion by microbial commensals and pathogens, and modulating the intestinal immune system. Communication between these epithelial cells and resident immune cells is crucial for maintaining homeostasis and coordinating appropriate responses to disease and can occur through cell-to-cell contact or by the release or recognition of soluble mediators. The objective of this review is to highlight recent literature illuminating how cytokines and chemokines, both those made by and acting on the intestinal epithelium, orchestrate many of the diverse functions of the intestinal epithelium and its interactions with immune cells in health and disease. Areas of focus include cytokine control of intestinal epithelial proliferation, cell death, and barrier permeability. In addition, the modulation of epithelial-derived cytokines and chemokines by factors such as interactions with stromal and immune cells, pathogen and commensal exposure, and diet will be discussed.

Regeneration of stem-cells in intestinal epithelium after irradiation

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Hendry, J.H.

1979-01-01

Stem-cells can be defined as pluripotent progenitor cells, capable of both self-renewal and differentitation into all the functional end-cells typical of that cell family. Intestinal crypts contain population of cells which is capable of a) self-renewal following the severe depletion after radiation injury, b) replacing all other cypt cell types, and c) regeneration following repeated depletion (in colon). These are the properties of stem cells. Most measurements of the rate of regeneration of these cells following the severe depletion by radiation have been made by employing large test dose at increasing times. Such measurements have produced widely differing rates of increase in the survival under the test dose, from 4 hours (macrocolonies in jejunum) to 43 hours (microcolonies in stomach). In other tissues, large single test doses have been used to derive the time of doubling survival ratio e.g. for epidermal clones. Although cryptogenic cell number per crypt can be virtually restored by day 4 after a single dose and probably after many such doses, the status quo cannot be reached until the number of crypts is restored to normal. Stem cell numbers form a necessary part of the integrity of epitheliums. The quality of the stem cell function of survivors as expressed in the differentiated progeny, and the maintenance of function of the supportive environment are equally important for late radiation damage. (Yamashita, S.)

The joint power of sex and stress to modulate brain-gut-microbiota axis and intestinal barrier homeostasis: implications for irritable bowel syndrome.

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Pigrau, M; Rodiño-Janeiro, B K; Casado-Bedmar, M; Lobo, B; Vicario, M; Santos, J; Alonso-Cotoner, C

2016-04-01

Intestinal homeostasis is a dynamic process that takes place at the interface between the lumen and the mucosa of the gastrointestinal tract, where a constant scrutiny for antigens and toxins derived from food and microorganisms is carried out by the vast gut-associated immune system. Intestinal homeostasis is preserved by the ability of the mucus layer and the mucosal barrier to keep the passage of small-sized and antigenic molecules across the epithelium highly selective. When combined and preserved, immune surveillance and barrier's selective permeability, the host capacity of preventing the development of intestinal inflammation is optimized, and viceversa. In addition, the brain-gut-microbiome axis, a multidirectional communication system that integrates distant and local regulatory networks through neural, immunological, metabolic, and hormonal signaling pathways, also regulates intestinal function. Dysfunction of the brain-gut-microbiome axis may induce the loss of gut mucosal homeostasis, leading to uncontrolled permeation of toxins and immunogenic particles, increasing the risk of appearance of intestinal inflammation, mucosal damage, and gut disorders. Irritable bowel syndrome is prevalent stress-sensitive gastrointestinal disorder that shows a female predominance. Interestingly, the role of stress, sex and gonadal hormones in the regulation of intestinal mucosal and the brain-gut-microbiome axis functioning is being increasingly recognized. We aim to critically review the evidence linking sex, and stress to intestinal barrier and brain-gut-microbiome axis dysfunction and the implications for irritable bowel syndrome. © 2015 John Wiley & Sons Ltd.

Cellular chloride and bicarbonate retention alters intracellular pH regulation in Cftr KO crypt epithelium.

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Walker, Nancy M; Liu, Jinghua; Stein, Sydney R; Stefanski, Casey D; Strubberg, Ashlee M; Clarke, Lane L

2016-01-15

Cystic fibrosis (CF) is caused by mutations in the CF transmembrane conductance regulator (CFTR), an anion channel providing a major pathway for Cl(-) and HCO3 (-) efflux across the apical membrane of the epithelium. In the intestine, CF manifests as obstructive syndromes, dysbiosis, inflammation, and an increased risk for gastrointestinal cancer. Cftr knockout (KO) mice recapitulate CF intestinal disease, including intestinal hyperproliferation. Previous studies using Cftr KO intestinal organoids (enteroids) indicate that crypt epithelium maintains an alkaline intracellular pH (pHi). We hypothesized that Cftr has a cell-autonomous role in downregulating pHi that is incompletely compensated by acid-base regulation in its absence. Here, 2',7'-bis(2-carboxyethyl)-5(6)-carboxyfluorescein microfluorimetry of enteroids showed that Cftr KO crypt epithelium sustains an alkaline pHi and resistance to cell acidification relative to wild-type. Quantitative real-time PCR revealed that Cftr KO enteroids exhibit downregulated transcription of base (HCO3 (-))-loading proteins and upregulation of the basolateral membrane HCO3 (-)-unloader anion exchanger 2 (Ae2). Although Cftr KO crypt epithelium had increased Ae2 expression and Ae2-mediated Cl(-)/HCO3 (-) exchange with maximized gradients, it also had increased intracellular Cl(-) concentration relative to wild-type. Pharmacological reduction of intracellular Cl(-) concentration in Cftr KO crypt epithelium normalized pHi, which was largely Ae2-dependent. We conclude that Cftr KO crypt epithelium maintains an alkaline pHi as a consequence of losing both Cl(-) and HCO3 (-) efflux, which impairs pHi regulation by Ae2. Retention of Cl(-) and an alkaline pHi in crypt epithelium may alter several cellular processes in the proliferative compartment of Cftr KO intestine. Copyright © 2016 the American Physiological Society.

Cellular chloride and bicarbonate retention alters intracellular pH regulation in Cftr KO crypt epithelium

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Walker, Nancy M.; Liu, Jinghua; Stein, Sydney R.; Stefanski, Casey D.; Strubberg, Ashlee M.

2015-01-01

Cystic fibrosis (CF) is caused by mutations in the CF transmembrane conductance regulator (CFTR), an anion channel providing a major pathway for Cl− and HCO3− efflux across the apical membrane of the epithelium. In the intestine, CF manifests as obstructive syndromes, dysbiosis, inflammation, and an increased risk for gastrointestinal cancer. Cftr knockout (KO) mice recapitulate CF intestinal disease, including intestinal hyperproliferation. Previous studies using Cftr KO intestinal organoids (enteroids) indicate that crypt epithelium maintains an alkaline intracellular pH (pHi). We hypothesized that Cftr has a cell-autonomous role in downregulating pHi that is incompletely compensated by acid-base regulation in its absence. Here, 2′,7′-bis(2-carboxyethyl)-5(6)-carboxyfluorescein microfluorimetry of enteroids showed that Cftr KO crypt epithelium sustains an alkaline pHi and resistance to cell acidification relative to wild-type. Quantitative real-time PCR revealed that Cftr KO enteroids exhibit downregulated transcription of base (HCO3−)-loading proteins and upregulation of the basolateral membrane HCO3−-unloader anion exchanger 2 (Ae2). Although Cftr KO crypt epithelium had increased Ae2 expression and Ae2-mediated Cl−/HCO3− exchange with maximized gradients, it also had increased intracellular Cl− concentration relative to wild-type. Pharmacological reduction of intracellular Cl− concentration in Cftr KO crypt epithelium normalized pHi, which was largely Ae2-dependent. We conclude that Cftr KO crypt epithelium maintains an alkaline pHi as a consequence of losing both Cl− and HCO3− efflux, which impairs pHi regulation by Ae2. Retention of Cl− and an alkaline pHi in crypt epithelium may alter several cellular processes in the proliferative compartment of Cftr KO intestine. PMID:26542396

Neural influences on human intestinal epithelium in vitro.

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Krueger, Dagmar; Michel, Klaus; Zeller, Florian; Demir, Ihsan E; Ceyhan, Güralp O; Slotta-Huspenina, Julia; Schemann, Michael

2016-01-15

We present the first systematic and, up to now, most comprehensive evaluation of the basic features of epithelial functions, such as basal and nerve-evoked secretion, as well as tissue resistance, in over 2200 surgical specimens of human small and large intestine. We found no evidence for impaired nerve-evoked epithelial secretion or tissue resistance with age or disease pathologies (stomach, pancreas or colon cancer, polyps, diverticulitis, stoma reversal). This indicates the validity of future studies on epithelial secretion or resistance that are based on data from a variety of surgical specimens. ACh mainly mediated nerve-evoked and basal secretion in the small intestine, whereas vasoactive intestinal peptide and nitric oxide were the primary pro-secretory transmitters in the large intestine. The results of the present study revealed novel insights into regional differences in nerve-mediated secretion in the human intestine and comprise the basis by which to more specifically target impaired epithelial functions in the diseased gut. Knowledge on basic features of epithelial functions in the human intestine is scarce. We used Ussing chamber techniques to record basal tissue resistance (R-basal) and short circuit currents (ISC; secretion) under basal conditions (ISC-basal) and after electrical field stimulation (ISC-EFS) of nerves in 2221 resectates from 435 patients. ISC-EFS was TTX-sensitive and of comparable magnitude in the small and large intestine. ISC-EFS or R-basal were not influenced by the patients' age, sex or disease pathologies (cancer, polyps, diverticulitis). Ion substitution, bumetanide or adenylate cyclase inhibition studies suggested that ISC-EFS depended on epithelial cAMP-driven chloride and bicarbonate secretion but not on amiloride-sensitive sodium absorption. Although atropine-sensitive cholinergic components prevailed for ISC-EFS of the duodenum, jejunum and ileum, PG97-269-sensitive [vasoactive intestinal peptide (VIP) receptor 1

Spontaneous and cytokine induced expression and activity of matrix metalloproteinases in human colonic epithelium

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Pedersen, G; Saermark, T; Kirkegaard, T

2009-01-01

levels in cells from inflamed IBD mucosa. MMP-2 and -8 mRNA were expressed inconsistently and MMP-11, -13 and -14 mRNA undetectable. Proteolytic MMP activity was detected in CEC supernatants and the level was increased significantly in inflamed IBD epithelium. The enzyme activity was inhibited strongly......Matrix metalloproteinases (MMPs) have been implicated in tissue damage associated with inflammatory bowel disease (IBD).As the role of the intestinal epithelium in this process is unknown, we determined MMP expression and enzyme activity in human colonic epithelial cells (CEC). MMP mRNA expression...... was assessed by reverse transcription-polymerase chain reaction in HT-29 and DLD-1 cells and in CEC isolated from biopsies from IBD and control patients. Total MMP activity in the cells was measured by a functional assay, based on degradation of a fluorescent synthetic peptide containing the specific bond...

Tissue-Specific Upregulation of MDS/EVI Gene Transcripts in the Intestine by Thyroid Hormone during Xenopus Metamorphosis

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Hasebe, Takashi; Fu, Liezhen; Heimeier, Rachel A.; Das, Biswajit; Ishizuya-Oka, Atsuko; Shi, Yun-Bo

2013-01-01

Background Intestinal remodeling during amphibian metamorphosis resembles the maturation of the adult intestine during mammalian postembryonic development when the adult epithelial self-renewing system is established under the influence of high concentrations of plasma thyroid hormone (T3). This process involves de novo formation and subsequent proliferation and differentiation of the adult stem cells. Methodology/Principal Findings The T3-dependence of the formation of adult intestinal stem cell during Xenopus laevis metamorphosis offers a unique opportunity to identify genes likely important for adult organ-specific stem cell development. We have cloned and characterized the ectopic viral integration site 1 (EVI) and its variant myelodysplastic syndrome 1 (MDS)/EVI generated via transcription from the upstream MDS promoter and alternative splicing. EVI and MDS/EVI have been implicated in a number of cancers including breast, leukemia, ovarian, and intestinal cancers. We show that EVI and MDS/EVI transcripts are upregulated by T3 in the epithelium but not the rest of the intestine in Xenopus laevis when adult stem cells are forming in the epithelium. Conclusions/Significance Our results suggest that EVI and MDS/EVI are likely involved in the development and/or proliferation of newly forming adult intestinal epithelial cells. PMID:23383234

Expressions of tight junction proteins Occludin and Claudin-1 are under the circadian control in the mouse large intestine: implications in intestinal permeability and susceptibility to colitis.

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Oh-oka Kyoko

Full Text Available BACKGROUND & AIMS: The circadian clock drives daily rhythms in behavior and physiology. A recent study suggests that intestinal permeability is also under control of the circadian clock. However, the precise mechanisms remain largely unknown. Because intestinal permeability depends on tight junction (TJ that regulates the epithelial paracellular pathway, this study investigated whether the circadian clock regulates the expression levels of TJ proteins in the intestine. METHODS: The expression levels of TJ proteins in the large intestinal epithelium and colonic permeability were analyzed every 4, 6, or 12 hours between wild-type mice and mice with a mutation of a key clock gene Period2 (Per2; mPer2(m/m. In addition, the susceptibility to dextran sodium sulfate (DSS-induced colitis was compared between wild-type mice and mPer2(m/m mice. RESULTS: The mRNA and protein expression levels of Occludin and Claudin-1 exhibited daily variations in the colonic epithelium in wild-type mice, whereas they were constitutively high in mPer2(m/m mice. Colonic permeability in wild-type mice exhibited daily variations, which was inversely associated with the expression levels of Occludin and Claudin-1 proteins, whereas it was constitutively low in mPer2(m/m mice. mPer2(m/m mice were more resistant to the colonic injury induced by DSS than wild-type mice. CONCLUSIONS: Occludin and Claudin-1 expressions in the large intestine are under the circadian control, which is associated with temporal regulation of colonic permeability and also susceptibility to colitis.

Clinical Implications of Intestinal Stem Cell Markers in Colorectal Cancer

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Espersen, Maiken Lise Marcker; Olsen, Jesper; Linnemann, Dorte

2015-01-01

Colorectal cancer (CRC) still has one of the highest incidence and mortality rate among cancers. Therefore, improved differential diagnostics and personalized treatment are still needed. Several intestinal stem cell markers have been found to be associated with CRC and might have a prognostic...... and predictive significance in CRC patients. This review provides an overview of the intestinal stem cell markers leucine-rich repeat-containing G-protein-coupled receptor 5 (LGR5), B cell–specific Moloney murine leukemia virus insertion site 1 (BMI1), Musashi1 (MSI1), and sex-determining region y-box 9 (SOX9......) and their implications in human CRC. The exact roles of the intestinal stem cell markers in CRC development and progression remain unclear; however, high expression of these stem cell markers have a potential prognostic significance and might be implicated in chemotherapy resistance...

Hippo signalling directs intestinal fate

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le Bouteiller, Marie Catherine M; Jensen, Kim Bak

2015-01-01

Hippo signalling has been associated with many important tissue functions including the regulation of organ size. In the intestinal epithelium differing functions have been proposed for the effectors of Hippo signalling, YAP and TAZ1. These are now shown to have a dual role in the intestinal...

Lymphoid cells in chicken intestinal epithelium

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Bjerregaard, P

1975-01-01

The intraepithelial lymphoid cells of chicken small intestine were studied by light microscopy using 1 mu Epon sections, and by electron microscopy. Three cell types were found: small lymphocytes, large lymphoid cells, and granular cells. These cells correspond to the theliolymphocytes and globule...

Intestinal Stem Cell Dynamics: A Story of Mice and Humans.

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Hodder, Michael C; Flanagan, Dustin J; Sansom, Owen J

2018-06-01

Stem cell dynamics define the probability of accumulating mutations within the intestinal epithelium. In this issue of Cell Stem Cell, Nicholson et al. (2018) report that human intestinal stem cell dynamics differ significantly from those of mice and establish that oncogenic mutations are more likely to expand; therefore, "normal" epithelium may carry multiple mutations. Copyright © 2018 Elsevier Inc. All rights reserved.

The mucosal firewalls against commensal intestinal microbes.

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Macpherson, Andrew J; Slack, Emma; Geuking, Markus B; McCoy, Kathy D

2009-07-01

Mammals coexist with an extremely dense microbiota in the lower intestine. Despite the constant challenge of small numbers of microbes penetrating the intestinal surface epithelium, it is very unusual for these organisms to cause disease. In this review article, we present the different mucosal firewalls that contain and allow mutualism with the intestinal microbiota.

Claudin expression in follicle-associated epithelium of rat Peyer's patches defines a major restriction of the paracellular pathway.

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Markov, A G; Falchuk, E L; Kruglova, N M; Radloff, J; Amasheh, S

2016-01-01

Members of the tight junction protein family of claudins have been demonstrated to specifically determine paracellular permeability of the intestinal epithelium. In small intestinal mucosa, which is generally considered to be a leaky epithelium, Peyer's patches are a primary part of the immune system. The aim of this study was to analyse the tight junctional barrier of follicle-associated epithelium covering Peyer's patches (lymphoid follicles). Employing small intestinal tissue specimens of male Wistar rats, electrophysiological analyses including the Ussing chamber technique, marker flux measurements and one-path impedance spectroscopy were performed. Morphometry of HE-stained tissue sections was taken into account. Claudin expression and localization was analysed by immunoblotting and confocal laser scanning immunofluorescence microscopy. Almost twofold higher parameters of epithelial and transepithelial tissue resistance and a markedly lower permeability for the paracellular permeability markers 4 and 20 kDa FITC-dextran were detected in follicle-associated epithelium compared to neighbouring villous epithelium. Analysis of claudin expression and localization revealed a stronger expression of major sealing proteins in follicle-associated epithelium, including claudin-1, claudin-4, claudin-5 and claudin-8. Therefore, the specific expression and localization of claudins is in accordance with barrier properties of follicle-associated epithelium vs. neighbouring villous epithelium. We demonstrate that follicle-associated epithelium is specialized to ensure maximum restriction of the epithelial paracellular pathway in Peyer's patches by selective sealing of tight junctions. This results in an exclusive transcellular pathway of epithelial cells as the limiting and mandatory route for a controlled presentation of antigens to the underlying lymphocytes under physiological conditions. © 2015 Scandinavian Physiological Society. Published by John Wiley & Sons Ltd.

Multilayered epithelium in a rat model and human Barrett's esophagus: Similar expression patterns of transcription factors and differentiation markers

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Yang Chung S

2008-01-01

Full Text Available Abstract Background In rats, esophagogastroduodenal anastomosis (EGDA without concomitant chemical carcinogen treatment leads to gastroesophageal reflux disease, multilayered epithelium (MLE, a presumed precursor in intestinal metaplasia, columnar-lined esophagus, dysplasia, and esophageal adenocarcinoma. Previously we have shown that columnar-lined esophagus in EGDA rats resembled human Barrett's esophagus (BE in its morphology, mucin features and expression of differentiation markers (Lab. Invest. 2004;84:753–765. The purpose of this study was to compare the phenotype of rat MLE with human MLE, in order to gain insight into the nature of MLE and its potential role in the development of BE. Methods Serial sectioning was performed on tissue samples from 32 EGDA rats and 13 patients with established BE. Tissue sections were immunohistochemically stained for a variety of transcription factors and differentiation markers of esophageal squamous epithelium and intestinal columnar epithelium. Results We detected MLE in 56.3% (18/32 of EGDA rats, and in all human samples. As expected, both rat and human squamous epithelium, but not intestinal metaplasia, expressed squamous transcription factors and differentiation markers (p63, Sox2, CK14 and CK4 in all cases. Both rat and human intestinal metaplasia, but not squamous epithelium, expressed intestinal transcription factors and differentiation markers (Cdx2, GATA4, HNF1α, villin and Muc2 in all cases. Rat MLE shared expression patterns of Sox2, CK4, Cdx2, GATA4, villin and Muc2 with human MLE. However, p63 and CK14 were expressed in a higher proportion of rat MLE compared to humans. Conclusion These data indicate that rat MLE shares similar properties to human MLE in its expression pattern of these markers, not withstanding small differences, and support the concept that MLE may be a transitional stage in the metaplastic conversion of squamous to columnar epithelium in BE.

Intestinal Stem Cell Niche: The Extracellular Matrix and Cellular Components

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Laween Meran

2017-01-01

Full Text Available The intestinal epithelium comprises a monolayer of polarised columnar cells organised along the crypt-villus axis. Intestinal stem cells reside at the base of crypts and are constantly nourished by their surrounding niche for maintenance, self-renewal, and differentiation. The cellular microenvironment including the adjacent Paneth cells, stromal cells, smooth muscle cells, and neural cells as well as the extracellular matrix together constitute the intestinal stem cell niche. A dynamic regulatory network exists among the epithelium, stromal cells, and the matrix via complex signal transduction to maintain tissue homeostasis. Dysregulation of these biological or mechanical signals could potentially lead to intestinal injury and disease. In this review, we discuss the role of different intestinal stem cell niche components and dissect the interaction between dynamic matrix factors and regulatory signalling during intestinal stem cell homeostasis.

Cdx function is required for maintenance of intestinal identity in the adult.

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Hryniuk, Alexa; Grainger, Stephanie; Savory, Joanne G A; Lohnes, David

2012-03-15

The homeodomain transcription factors Cdx1 and Cdx2 are expressed in the intestinal epithelium from early development, with expression persisting throughout the life of the animal. While our understanding of the function of Cdx members in intestinal development has advanced significantly, their roles in the adult intestine is relatively poorly understood. In the present study, we found that ablation of Cdx2 in the adult small intestine severely impacted villus morphology, proliferation and intestinal gene expression patterns, resulting in the demise of the animal. Long-term loss of Cdx2 in a chimeric model resulted in loss of all differentiated intestinal cell types and partial conversion of the mucosa to a gastric-like epithelium. Concomitant loss of Cdx1 did not exacerbate any of these phenotypes. Loss of Cdx2 in the colon was associated with a shift to a cecum-like epithelial morphology and gain of cecum-associated genes which was more pronounced with subsequent loss of Cdx1. These findings suggest that Cdx2 is essential for differentiation of the small intestinal epithelium, and that both Cdx1 and Cdx2 contribute to homeostasis of the colon. Copyright © 2012 Elsevier Inc. All rights reserved.

Muscarinic cholinergic and alpha 2-adrenergic receptors in the epithelium and muscularis of the human ileum

International Nuclear Information System (INIS)

Lepor, H.; Rigaud, G.; Shapiro, E.; Baumann, M.; Kodner, I.J.; Fleshman, J.W.

1990-01-01

The aim of this study was to characterize the binding and functional properties of muscarinic cholinergic (MCh) and alpha 2-adrenergic receptors in the human ileum to provide insight into pharmacologic strategies for managing urinary and fecal incontinence after bladder and rectal replacement with intestinal segments. MCh and alpha 2-adrenergic binding sites were characterized in the epithelium and muscularis of eight human ileal segments with 3H-N-methylscopolamine and 3H-rauwolscine, respectively. The dissociation constant for 3H-N-methylscopolamine in the epithelium and muscularis was 0.32 +/- 0.07 nmol/L and 0.45 +/- 0.10 nmol/L, respectively (p = 0.32). The MCh receptor content was approximately eightfold greater in the muscularis compared with the epithelium (p = 0.008). The dissociation constant for 3H-rauwolscine in the muscularis and epithelium was 2.55 +/- 0.42 nmol/L and 2.03 +/- 0.19 nmol/L, respectively (p = 0.29). The alpha 2-adrenoceptor density was twofold greater in the epithelium compared with the muscularis (p = 0.05). Noncumulative concentration-response experiments were performed with carbachol, an MCh agonist, and UK-14304, a selective alpha 2-adrenergic agonist. The epithelium did not contract in the presence of high concentrations of carbachol and UK-14304. The muscularis preparations were responsive only to carbachol. The muscularis contains primarily MCh receptors mediating smooth muscle contraction. The alpha 2-adrenoceptors are localized primarily to the epithelium and may regulate water secretion in the intestine. The distribution and functional properties of ileal MCh and alpha 2-adrenergic receptors provide a theoretic basis for the treatment of incontinence after bladder and rectal replacement with intestinal segments

Zinc Transporter SLC39A7/ZIP7 Promotes Intestinal Epithelial Self-Renewal by Resolving ER Stress

Science.gov (United States)

Ohashi, Wakana; Kimura, Shunsuke; Iwanaga, Toshihiko; Furusawa, Yukihiro; Irié, Tarou; Izumi, Hironori; Watanabe, Takashi; Hara, Takafumi; Ohara, Osamu; Koseki, Haruhiko; Sato, Toshiro; Robine, Sylvie; Mori, Hisashi; Hattori, Yuichi; Mishima, Kenji; Ohno, Hiroshi; Hase, Koji; Fukada, Toshiyuki

2016-01-01

Zinc transporters play a critical role in spatiotemporal regulation of zinc homeostasis. Although disruption of zinc homeostasis has been implicated in disorders such as intestinal inflammation and aberrant epithelial morphology, it is largely unknown which zinc transporters are responsible for the intestinal epithelial homeostasis. Here, we show that Zrt-Irt-like protein (ZIP) transporter ZIP7, which is highly expressed in the intestinal crypt, is essential for intestinal epithelial proliferation. Mice lacking Zip7 in intestinal epithelium triggered endoplasmic reticulum (ER) stress in proliferative progenitor cells, leading to significant cell death of progenitor cells. Zip7 deficiency led to the loss of Olfm4+ intestinal stem cells and the degeneration of post-mitotic Paneth cells, indicating a fundamental requirement for Zip7 in homeostatic intestinal regeneration. Taken together, these findings provide evidence for the importance of ZIP7 in maintenance of intestinal epithelial homeostasis through the regulation of ER function in proliferative progenitor cells and maintenance of intestinal stem cells. Therapeutic targeting of ZIP7 could lead to effective treatment of gastrointestinal disorders. PMID:27736879

Zinc Transporter SLC39A7/ZIP7 Promotes Intestinal Epithelial Self-Renewal by Resolving ER Stress.

Directory of Open Access Journals (Sweden)

Wakana Ohashi

2016-10-01

Full Text Available Zinc transporters play a critical role in spatiotemporal regulation of zinc homeostasis. Although disruption of zinc homeostasis has been implicated in disorders such as intestinal inflammation and aberrant epithelial morphology, it is largely unknown which zinc transporters are responsible for the intestinal epithelial homeostasis. Here, we show that Zrt-Irt-like protein (ZIP transporter ZIP7, which is highly expressed in the intestinal crypt, is essential for intestinal epithelial proliferation. Mice lacking Zip7 in intestinal epithelium triggered endoplasmic reticulum (ER stress in proliferative progenitor cells, leading to significant cell death of progenitor cells. Zip7 deficiency led to the loss of Olfm4+ intestinal stem cells and the degeneration of post-mitotic Paneth cells, indicating a fundamental requirement for Zip7 in homeostatic intestinal regeneration. Taken together, these findings provide evidence for the importance of ZIP7 in maintenance of intestinal epithelial homeostasis through the regulation of ER function in proliferative progenitor cells and maintenance of intestinal stem cells. Therapeutic targeting of ZIP7 could lead to effective treatment of gastrointestinal disorders.

Expression of an Intestine-Specific Transcription Factor (CDX1) in Intestinal Metaplasia and in Subsequently Developed Intestinal Type of Cholangiocarcinoma in Rat Liver

Science.gov (United States)

Ren, Ping; Silberg, Debra G.; Sirica, Alphonse E.

2000-01-01

CDX1 is a caudal-type homeobox intestine-specific transcription factor that has been shown to be selectively expressed in epithelial cells in intestinal metaplasia of the human stomach and esophagus and variably expressed in human gastric and esophageal adenocarcinomas (Silberg DG, Furth EE, Taylor JK, Schuck T, Chiou T, Traber PG: Gastroenterology 1997, 113: 478–486). Through the use of immunohistochemistry and Western blotting, we investigated whether CDX1 is also uniquely associated with the intestinal metaplasia associated with putative precancerous cholangiofibrosis induced in rat liver during furan cholangiocarcinogenesis, as well as expressed in neoplastic glands in a subsequently developed intestinal type of cholangiocarcinoma. In normal, control adult rat small intestine, specific nuclear immunoreactivity for CDX1 was most prominent in enterocytes lining the crypts. In comparison, epithelium from intestinal metaplastic glands within furan-induced hepatic cholangiofibrosis and neoplastic epithelium from later developed primary intestinal-type cholangiocarcinoma each demonstrated strong nuclear immunoreactivity for CDX1. CDX1-positive cells were detected in hepatic cholangiofibrotic tissue as early as 3 weeks after the start of chronic furan treatment. We further determined that the percentages of CDX1-positive neoplastic glands and glandular nuclei are significantly higher in primary tumors than in a derived, transplantable cholangiocarcinoma serially-propagated in vivo. Western blotting confirmed our immunohistochemical results, and no CDX1 immunoreactivity was detected in normal adult rat liver or in hyperplastic biliary epithelial cells. These findings indicate that CDX1 is specifically associated with early intestinal metaplasia and a later developed intestinal-type of cholangiocarcinoma induced in the liver of furan-treated rats. PMID:10666391

Campylobacter jejuni induces transcytosis of commensal bacteria across the intestinal epithelium through M-like cells

Science.gov (United States)

2010-01-01

Background Recent epidemiological analyses have implicated acute Campylobacter enteritis as a factor that may incite or exacerbate inflammatory bowel disease (IBD) in susceptible individuals. We have demonstrated previously that C. jejuni disrupts the intestinal barrier function by rapidly inducing epithelial translocation of non-invasive commensal bacteria via a transcellular lipid raft-mediated mechanism ('transcytosis'). To further characterize this mechanism, the aim of this current study was to elucidate whether C. jejuni utilizes M cells to facilitate transcytosis of commensal intestinal bacteria. Results C. jejuni induced translocation of non-invasive E. coli across confluent Caco-2 epithelial monolayers in the absence of disrupted transepithelial electrical resistance or increased permeability to a 3 kDa dextran probe. C. jejuni-infected monolayers displayed increased numbers of cells expressing the M cell-specific marker, galectin-9, reduced numbers of enterocytes that stained with the absorptive enterocyte marker, Ulex europaeus agglutinin-1, and reduced activities of enzymes typically associated with absorptive enterocytes (namely alkaline phosphatase, lactase, and sucrase). Furthermore, in Campylobacter-infected monolayers, E. coli were observed to be internalized specifically within epithelial cells displaying M-like cell characteristics. Conclusion These data indicate that C. jejuni may utilize M cells to promote transcytosis of non-invasive bacteria across the intact intestinal epithelial barrier. This mechanism may contribute to the inflammatory immune responses against commensal intestinal bacteria commonly observed in IBD patients. PMID:21040540

Campylobacter jejuni induces transcytosis of commensal bacteria across the intestinal epithelium through M-like cells

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Kalischuk Lisa D

2010-11-01

Full Text Available Abstract Background Recent epidemiological analyses have implicated acute Campylobacter enteritis as a factor that may incite or exacerbate inflammatory bowel disease (IBD in susceptible individuals. We have demonstrated previously that C. jejuni disrupts the intestinal barrier function by rapidly inducing epithelial translocation of non-invasive commensal bacteria via a transcellular lipid raft-mediated mechanism ('transcytosis'. To further characterize this mechanism, the aim of this current study was to elucidate whether C. jejuni utilizes M cells to facilitate transcytosis of commensal intestinal bacteria. Results C. jejuni induced translocation of non-invasive E. coli across confluent Caco-2 epithelial monolayers in the absence of disrupted transepithelial electrical resistance or increased permeability to a 3 kDa dextran probe. C. jejuni-infected monolayers displayed increased numbers of cells expressing the M cell-specific marker, galectin-9, reduced numbers of enterocytes that stained with the absorptive enterocyte marker, Ulex europaeus agglutinin-1, and reduced activities of enzymes typically associated with absorptive enterocytes (namely alkaline phosphatase, lactase, and sucrase. Furthermore, in Campylobacter-infected monolayers, E. coli were observed to be internalized specifically within epithelial cells displaying M-like cell characteristics. Conclusion These data indicate that C. jejuni may utilize M cells to promote transcytosis of non-invasive bacteria across the intact intestinal epithelial barrier. This mechanism may contribute to the inflammatory immune responses against commensal intestinal bacteria commonly observed in IBD patients.

Wnt, stem cells and cancer in the intestine.

NARCIS (Netherlands)

Pinto, D.; Clevers, J.C.

2005-01-01

The intestinal epithelium is a self-renewing tissue which represents a unique model for studying interconnected cellular processes such as proliferation, differentiation, cell migration and carcinogenesis. Although the stem cells of the intestine have not yet been physically characterized or

Stem cell self-renewal in intestinal crypt

NARCIS (Netherlands)

Simons, B.D.; Clevers, H.

2011-01-01

As a rapidly cycling tissue capable of fast repair and regeneration, the intestinal epithelium has emerged as a favored model system to explore the principles of adult stem cell biology. However, until recently, the identity and characteristics of the stem cell population in both the small intestine

c-Kit mutation reduce intestinal epithelial cell proliferation and migration, but not influence intestinal permeability stimulated by lipopolysaccharide.

Science.gov (United States)

Xue, Hong; Wang, Feng Yun; Kang, Qian; Tang, Xu Dong

2018-06-20

The proto-oncogene c-kit, as a marker of interstitial cells of Cajal (ICCs) in the gastrointestinal tract, plays an important role in the ICCs. Although limited evidences showed c-kit is present in the colonic epithelium but its roles remain unclear. In the present study, we aimed to investigate the expression, location and function of c-kit in the intestinal epithelium. Immunofluorescence, western blotting, and RT-PCR were performed to detect the expression and location of c-kit in the intestinal mucosa of WT mice. We investigated intestinal epithelial proliferation and migration in vivo by performing 5-Bromodeoxyuridine (BrdU) incorporation and Ki-67 staining in WT and Wads m/m mice. An Ussing chamber with fluorescein-isothiocyanate dextran 4000 was used to detect the transepithelial electric resistance (TER), short circuit current (ISC) and permeability across ex vivo colon segments under control and endotoxaemia conditions. We demonstrated that c-kit was located and expressed in the gut crypt compartment in WT mice, which was demonstrated in the c-kit mutant mice (Wads m/m ). In addition, both the number of proliferating cells and the percentage of the distance migrated were lower in the Wads m/m mice than those in the WT mice. Moreover, the intestinal permeability, TER and tight junction were unaltered in the Wads m/m mice under endotoxic conditions compared with those in both the control condition and the WT mice. Altogether, these observations imply that the expression of c-kit in the colonic epithelium is involved in the proliferation and permeability of the colonic epithelium. Copyright © 2018. Published by Elsevier GmbH.

Cloning of radiation-induced new gene RS1 expressed in mouse intestinal epithelium by enhanced RACE

International Nuclear Information System (INIS)

Wang Fengchao; Wang Junping; Su Yongping; Gao Jinsheng; Lou Shufen; Liu Xiaohong; Ren Jiong; Zhang Bo

2003-01-01

Objective: To obtain full-length cDNA of radiation-induced new gene RS1 expressed in mouse intestinal epithelium. Methods: The tissue expression profile of RS1 was analyzed by semi-quantitative RT-PCR to find the target tissue which highly expresses RS1. The total RNA extracted from the corresponding tissue was taken as the template for reverse-transcription. Enhanced RACE PCR was used to clone the full-length cDNA of RS1, including enrichment of the target gene through biotin-labeled probe for magnetic bead purification and nested PCR. Results: About a 2 kb long 3' end was successfully cloned and cloning of the 5' end proceeded well. Conclusion: The result is consistent with our experiment design. The set of combined techniques has been identified with the cloning of full-length cDNA from EST sequence especially when the optimal gene-specific primers are not available or the expression level of target gene is low

Mannose-specific interaction of Lactobacillus plantarum with porcine jejunal epithelium

NARCIS (Netherlands)

Pretzer, G.; Meulen, van der J.; Snel, J.; Meer, van der R.; Kleerebezem, M.; Niewold, Th.; Hulst, M.M.; Smits, M.A.

2008-01-01

Host-microorganism interactions in the intestinal tract are complex, and little is known about specific nonpathogenic microbial factors triggering host responses in the gut. In this study, mannose-specific interactions of Lactobacillus plantarum 299v with jejunal epithelium were investigated using

Phagocytosis of Giardia muris by macrophages in Peyer's patch epithelium in mice.

OpenAIRE

Owen, R L; Allen, C L; Stevens, D P

1981-01-01

No mechanism for the initiation of immunological clearance of Giardia from the mammalian intestinal tract has been identified. In normal and nude mice experimentally infected with G. muris, we examined antigen-sampling epithelium over Peyer's patch follicles by electron microscopy for evidence of interaction between G. muris and lymphoid cells. Invading G. muris were found in the epithelium near dying or desquamating columnar cells. Macrophages beneath the basal lamina extended pseudopods int...

Transepithelial Transport of PAMAM Dendrimers Across Isolated Human Intestinal Tissue.

Science.gov (United States)

Hubbard, Dallin; Enda, Michael; Bond, Tanner; Moghaddam, Seyyed Pouya Hadipour; Conarton, Josh; Scaife, Courtney; Volckmann, Eric; Ghandehari, Hamidreza

2015-11-02

Poly(amido amine) (PAMAM) dendrimers have shown transepithelial transport across intestinal epithelial barrier in rats and across Caco-2 cell monolayers. Caco-2 models innately lack mucous barriers, and rat isolated intestinal tissue has been shown to overestimate human permeability. This study is the first report of transport of PAMAM dendrimers across isolated human intestinal epithelium. It was observed that FITC labeled G4-NH2 and G3.5-COOH PAMAM dendrimers at 1 mM concentration do not have a statistically higher permeability compared to free FITC controls in isolated human jejunum and colonic tissues. Mannitol permeability was increased at 10 mM concentrations of G3.5-COOH and G4-NH2 dendrimers. Significant histological changes in human colonic and jejunal tissues were observed at G3.5-COOH and G4-NH2 concentrations of 10 mM implying that dose limiting toxicity may occur at similar concentrations in vivo. The permeability through human isolated intestinal tissue in this study was compared to previous rat and Caco-2 permeability data. This study implicates that PAMAM dendrimer oral drug delivery may be feasible, but it may be limited to highly potent drugs.

Transplantation of Expanded Fetal Intestinal Progenitors Contributes to Colon Regeneration after Injury

DEFF Research Database (Denmark)

Fordham, Robert P; Yui, Shiro; Hannan, Nicholas R F

2013-01-01

Regeneration and homeostasis in the adult intestinal epithelium is driven by proliferative resident stem cells, whose functional properties during organismal development are largely unknown. Here, we show that human and mouse fetal intestine contains proliferative, immature progenitors, which can...... be expanded in vitro as Fetal Enterospheres (FEnS). A highly similar progenitor population can be established during intestinal differentiation of human induced pluripotent stem cells. Established cultures of mouse fetal intestinal progenitors express lower levels of Lgr5 than mature progenitors and propagate...... in the presence of the Wnt antagonist Dkk1, and new cultures can be induced to form mature intestinal organoids by exposure to Wnt3a. Following transplantation in a colonic injury model, FEnS contribute to regeneration of colonic epithelium by forming epithelial crypt-like structures expressing region...

Mucin-Microbiota Interaction During Postnatal Maturation of the Intestinal Ecosystem: Clinical Implications.

Science.gov (United States)

Rokhsefat, Sana; Lin, Aifeng; Comelli, Elena M

2016-06-01

The mucus layer and gut microbiota interplay contributes to host homeostasis. The mucus layer serves as a scaffold and a carbon source for gut microorganisms; conversely, gut microorganisms, including mucin degraders, influence mucin gene expression, glycosylation, and secretion. Conjointly they shield the epithelium from luminal pathogens, antigens, and toxins. Importantly, the mucus layer and gut microbiota are established in parallel during early postnatal life. During this period, the development of gut microbiota and mucus layer is coupled with that of the immune system. Developmental changes of different mucin types can impact the age-dependent patterns of intestinal infection in terms of incidence and severity. Altered mucus layer, dysbiotic microbiota, and abnormal mucus-gut microbiota interaction have the potential for inducing systemic effects, and accompany several intestinal diseases such as inflammatory bowel disease, colorectal cancer, and radiation-induced mucositis. Early life provides a pivotal window of opportunity to favorably modulate the mucus-microbiota interaction. The support of a health-compatible mucin-microbiota maturation in early life is paramount for long-term health and serves as an important opportunity for clinical intervention.

Impaired Growth of Small Intestinal Epithelium by Adrenalectomy in Weaning Rats

International Nuclear Information System (INIS)

Miyata, Tohru; Minai, Yuji; Haga, Minoru

2008-01-01

Functional maturation of the small intestine occurs during the weaning period in rats. It is known that this development is facilitated by glucocorticoid. However, the effect of glucocorticoid on morphological development of small intestine has yet to be clarified. The present study evaluated the morphological development and cell proliferation of the small intestine in adrenalectomized (ADX) rat pups. To further understand the mechanism of glucocorticoid effects on intestinal development, we examined the localization of the glucocorticoid receptor in the small intestine. Microscopic analysis showed that growth of villi and crypts is age-dependent, and is significantly attenuated in ADX rats compared with sham-operated rats. BrdU-positive cells, i.e. proliferating cells, were primarily observed in crypt compartments and rapidly increased in number during the early weaning period. The increase in BrdU-positive cells could be attenuated by adrenalectomy. The morphological development of small intestine may be associated with increased proliferation of epithelial cells. On the other hand, glucocorticoid receptors were found in epithelial cells of the mid- and lower villi and not in crypts where BrdU-positive cells were localized. These results indicate that the growth of small intestine is attenuated by adrenalectomy, and that glucocorticoid indirectly acts on proliferation of epithelial cells during the weaning period

Transport across the choroid plexus epithelium

DEFF Research Database (Denmark)

Praetorius, Jeppe; Damkier, Helle Hasager

2017-01-01

The choroid plexus epithelium is a secretory epithelium par excellence. However, this is perhaps not the most prominent reason for the massive interest in this modest-sized tissue residing inside the brain ventricles. Most likely, the dominant reason for extensive studies of the choroid plexus...... is the identification of this epithelium as the source of the majority of intraventricular cerebrospinal fluid. This finding has direct relevance for studies of diseases and conditions with deranged central fluid volume or ionic balance. While the concept is supported by the vast majority of the literature......, the implication of the choroid plexus in secretion of the cerebrospinal fluid was recently challenged once again. Three newer and promising areas of current choroid plexus-related investigations are as follows: 1) the choroid plexus epithelium as the source of mediators necessary for central nervous system...

Wnt target gene analysis in colorectal cancer and intestinal stem cells

NARCIS (Netherlands)

van der Flier, L.G.

2009-01-01

The intestinal epithelium is a specialized simple epithelium that lines the gut and performs primary functions of digestion, absorption and forms a barrier against luminal pathogens. It is organized in invaginations called crypts and finger-like protrusions called villi. The crypts harbor

Intestinal T lymphocytes of different rat strains in immunotoxicity

NARCIS (Netherlands)

Bruder, M.C.; Spanhaak, S.; Bruijntjes, J.P.; Michielsen, C.P.P.C.; Vos, J.G.; Kuper, C.F.

1999-01-01

In order to study the intestinal mucosal immune cells, with emphasis on single T lymphocytcs, an inventory was made of single and organized lymphocytes in the epithelium and lamina propria of the small intestines of untreated Wistar, Fischer 344, and Lewis rats. The single and organized lymphocytes

Low uptake of silica nanoparticles in Caco-2 intestinal epithelial barriers

NARCIS (Netherlands)

Ye, Dong; Bramini, Mattia; Hristov, Delyan R.; Wan, Sha; Salvati, Anna; Åberg, Christoffer; Dawson, Kenneth A.

2017-01-01

Cellular barriers, such as the skin, the lung epithelium or the intestinal epithelium, constitute one of the first obstacles facing nanomedicines or other nanoparticles entering organisms. It is thus important to assess the capacity of nanoparticles to enter and transport across such barriers. In

Signal transduction pathways involved in intestinal salt and water secretion

NARCIS (Netherlands)

W. van den Berghe (Nina)

1992-01-01

textabstractThis thesis describes some novel aspects of the regulation of salt and water secretion in the intestinal epithelium. This process is not unique for the intestine, but a common and necessary function of many other organs, including the stomach (gastric juice), kidney (urine), sweatglands

Extensive intestinal metaplasia of renal pelvis: Report of a case and literature review

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Prakriti Shukla

2015-01-01

Full Text Available Transformation of the urothelium to the intestinal type of epithelium is rare in the pelvis with very few cases reported in the literature. The present study reports extensive intestinal metaplasia of the pelvi-calyceal system without residual urothelium in a 35-years-old woman with a 2 years history of renal calculi. Right - sided Nephrectomy was undertaken. Immunohistochemistry of the metaplastic epithelium revealed positive expression of CK20, low Ki-67 index and negative expression of p53. In this patient long standing metaplastic changes did not progress to adenocarcinoma which indicates that extensive intestinal metaplasia is not always associated with malignancy.

GATA4 Regulates Epithelial Cell Proliferation to Control Intestinal Growth and Development in MiceSummary

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Bridget M. Kohlnhofer

2016-03-01

Full Text Available Background & Aims: The embryonic small intestinal epithelium is highly proliferative, and although much is known about mechanisms regulating proliferation in the adult intestine, the mechanisms controlling epithelial cell proliferation in the developing intestine are less clear. GATA4, a transcription factor that regulates proliferation in other developing tissues, is first expressed early in the developing gut in midgut endoderm. GATA4 function within midgut endoderm and the early intestinal epithelium is unknown. Methods: By using Sonic Hedgehog Cre to eliminate GATA4 in the midgut endoderm of mouse embryos, we determined the impact of loss of GATA4 on intestinal development, including epithelial cell proliferation, between embryonic day (E9.5 and E18.5. Results: We found that intestinal length and width were decreased in GATA4 mutants compared with controls. GATA4-deficient intestinal epithelium contained fewer cells, and epithelial girth was decreased. We further observed a decreased proportion of proliferating epithelial cells at E10.5 and E11.5 in GATA4 mutants. We showed that GATA4 binds to chromatin containing GATA4 consensus binding sites within cyclin D2 (Ccnd2, cyclin-dependent kinase 6 (Cdk6, and frizzled 5 (Fzd5. Moreover, Ccnd2, Cdk6, and Fzd5 transcripts were reduced at E11.5 in GATA4 mutant tissue. Villus morphogenesis was delayed, and villus structure was abnormal in GATA4 mutant intestine. Conclusions: Our data identify GATA4 as an essential regulator of early intestinal epithelial cell proliferation. We propose that GATA4 controls proliferation in part by directly regulating transcription of cell-cycle mediators. Our data further suggest that GATA4 affects proliferation through transcriptional regulation of Fzd5, perhaps by influencing the response of the epithelium to WNT signaling. Keywords: Transcriptional Regulation, WNT Signaling, Villus Morphogenesis

Compartmentalization of Aquaporins in the Human Intestine

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Rajendram V. Rajnarayanan

2008-06-01

Full Text Available Improper localization of water channel proteins called aquaporins (AQP induce mucosal injury which is implicated in Crohn’s disease and ulcerative colitis. The amino acid sequences of AQP3 and AQP10 are 79% similar and belong to the mammalian aquaglyceroporin subfamily. AQP10 is localized on the apical compartment of the intestinal epithelium called the glycocalyx while AQP3 is selectively targeted to the basolateral membrane. Despite the high sequence similarity and evolutionary relatedness, the molecular mechanism involved in the polarity, selective targeting and function of AQP3 and AQP10 in the intestine is largely unknown. Our hypothesis is that the differential polarity and selective targeting of AQP3 and AQP10 in the intestinal epithelial cells is influenced by amino acid signal motifs. We performed sequence and structural alignments to determine differences in signals for localization and posttranslational glycosylation. The basolateral sorting motif “YRLL” is present in AQP3 but absent in AQP10; while Nglycosylation signals are present in AQP10 but absent in AQP3. Furthermore, the C-terminal region of AQP3 is longer compared to AQP10. The sequence and structural differences between AQP3 and AQP10 provide insights into the differential compartmentalization and function of these two aquaporins commonly expressed in human intestines.

A pSMAD/CDX2 Complex Is Essential for the Intestinalization of Epithelial Metaplasia

Directory of Open Access Journals (Sweden)

Luigi Mari

2014-05-01

Full Text Available The molecular mechanisms leading to epithelial metaplasias are poorly understood. Barrett's esophagus is a premalignant metaplastic change of the esophageal epithelium into columnar epithelium, occurring in patients suffering from gastroesophageal reflux disease. Mechanisms behind the development of the intestinal subtype, which is associated with the highest cancer risk, are unclear. In humans, it has been suggested that a nonspecialized columnar metaplasia precedes the development of intestinal metaplasia. Here, we propose that a complex made up of at least two factors needs to be activated simultaneously to drive the expression of intestinal type of genes. Using unique animal models and robust in vitro assays, we show that the nonspecialized columnar metaplasia is a precursor of intestinal metaplasia and that pSMAD/CDX2 interaction is essential for the switch toward an intestinal phenotype.

Polycomb Repressive Complex 2 Enacts Wnt Signaling in Intestinal Homeostasis and Contributes to the Instigation of Stemness in Diseases Entailing Epithelial Hyperplasia or Neoplasia.

Science.gov (United States)

Oittinen, Mikko; Popp, Alina; Kurppa, Kalle; Lindfors, Katri; Mäki, Markku; Kaikkonen, Minna U; Viiri, Keijo

2017-02-01

Canonical Wnt/β-catenin signaling regulates the homeostasis of intestinal epithelium by controlling the balance between intestinal stem cell self-renewal and differentiation but epigenetic mechanisms enacting the process are not known. We hypothesized that epigenetic regulator, Polycomb Repressive Complex-2 (PRC2), is involved in Wnt-mediated epithelial homeostasis on the crypt-villus axis and aberrancies therein are implicated both in celiac disease and in intestinal malignancies. We found that PRC2 establishes repressive crypt and villus specific trimethylation of histone H3 lysine 27 (H3K27me3) signature on genes responsible for, for example, nutrient transport and cell killing in crypts and, for example, proliferation and differentiation in mature villi, suggesting that PRC2 facilitates the Wnt-governed intestinal homeostasis. When celiac patients are on gluten-containing diet PRC2 is out-of-bounds active and consequently its target genes were found affected in intestinal epithelium. Significant set of effective intestinal PRC2 targets are also differentially expressed in colorectal adenoma and carcinomas. Our results suggest that PRC2 gives rise and maintains polar crypt and villus specific H3K27me3 signatures. As H3K27me3 is a mark enriched in developmentally important genes, identified intestinal PRC2 targets are possibly imperative drivers for enterocyte differentiation and intestinal stem cell maintenance downstream to Wnt-signaling. Our work also elucidates the mechanism sustaining the crypt hyperplasia in celiac disease and suggest that PRC2-dependent fostering of epithelial stemness is a common attribute in intestinal diseases in which epithelial hyperplasia or neoplasia prevails. Finally, this work demonstrates that in intestine PRC2 represses genes having both pro-stemness and pro-differentiation functions, fact need to be considered when designing epigenetic therapies including PRC2 as a drug target. Stem Cells 2017;35:445-457. © 2016 Alpha

Maintenance of the adult Drosophila intestine: all roads lead to homeostasis.

Science.gov (United States)

Guo, Zheng; Lucchetta, Elena; Rafel, Neus; Ohlstein, Benjamin

2016-10-01

Maintenance of tissue homeostasis is critical in tissues with high turnover such as the intestinal epithelium. The intestinal epithelium is under constant cellular assault due to its digestive functions and its function as a barrier to chemical and bacterial insults. The resulting high rate of cellular turnover necessitates highly controlled mechanisms of regeneration to maintain the integrity of the tissue over the lifetime of the organism. Transient increase in stem cell proliferation is a commonly used and elaborate mechanism to ensure fast and efficient repair of the gut. However, tissue repair is not limited to regulating ISC proliferation, as emerging evidence demonstrates that the Drosophila intestine uses multiple strategies to ensure proper tissue homeostasis that may also extend to other tissues. Copyright © 2016 Elsevier Ltd. All rights reserved.

Human organoids: a model system for intestinal diseases

OpenAIRE

Wiegerinck, C.L.

2015-01-01

You are what you eat. A common saying that indicates that your physical or mental state can be influenced by your choice of food. Unfortunately, not all people have the luxury to choose what to eat; this can be related to place of birth, social, economic state, or the physical inability of the diseased intestine to take up certain food. A cell layer, the epithelium, covers the intestine, and harbors the main functions of the intestine: uptake, digestion of food, and a barrier against unwanted...

Focal Adhesion Kinase Is Required for Intestinal Regeneration and Tumorigenesis Downstream of Wnt/c-Myc Signaling

Science.gov (United States)

Ashton, Gabrielle H.; Morton, Jennifer P.; Myant, Kevin; Phesse, Toby J.; Ridgway, Rachel A.; Marsh, Victoria; Wilkins, Julie A.; Athineos, Dimitris; Muncan, Vanesa; Kemp, Richard; Neufeld, Kristi; Clevers, Hans; Brunton, Valerie; Winton, Douglas J.; Wang, Xiaoyan; Sears, Rosalie C.; Clarke, Alan R.; Frame, Margaret C.; Sansom, Owen J.

2012-01-01

SUMMARY The intestinal epithelium has a remarkable capacity to regenerate after injury and DNA damage. Here, we show that the integrin effector protein Focal Adhesion Kinase (FAK) is dispensable for normal intestinal homeostasis and DNA damage signaling, but is essential for intestinal regeneration following DNA damage. Given Wnt/c-Myc signaling is activated following intestinal regeneration, we investigated the functional importance of FAK following deletion of the Apc tumor suppressor protein within the intestinal epithelium. Following Apc loss, FAK expression increased in a c-Myc-dependent manner. Codeletion of Apc and Fak strongly reduced proliferation normally induced following Apc loss, and this was associated with reduced levels of phospho-Akt and suppression of intestinal tumorigenesis in Apc heterozygous mice. Thus, FAK is required downstream of Wnt Signaling, for Akt/mTOR activation, intestinal regeneration, and tumorigenesis. Importantly, this work suggests that FAK inhibitors may suppress tumorigenesis in patients at high risk of developing colorectal cancer. PMID:20708588

Indian Hedgehog Suppresses a Stromal Cell-Driven Intestinal Immune Response.

Science.gov (United States)

Westendorp, B Florien; Büller, Nikè V J A; Karpus, Olga N; van Dop, Willemijn A; Koster, Jan; Versteeg, Rogier; Koelink, Pim J; Snel, Clinton Y; Meisner, Sander; Roelofs, Joris J T H; Uhmann, Anja; Ver Loren van Themaat, Emiel; Heijmans, Jarom; Hahn, Heidi; Muncan, Vanesa; Wildenberg, Manon E; van den Brink, Gijs R

2018-01-01

Upon intestinal epithelial damage a complex wound healing response is initiated to restore epithelial integrity and defend against pathogenic invasion. Epithelium-derived Indian Hedgehog (Ihh) functions as a critical sensor in this process. Signaling occurs in a paracrine manner because the receptor for Ihh is expressed only in the mesenchyme, but the exact Hedgehog target cell has remained elusive. The aim of this study was to elucidate further the nature of this target cell in the context of intestinal inflammation. Hedgehog activity was modulated genetically in both cell type-specific and body-wide models and the resulting animals were analyzed for gene expression profiles and sensitivity for dextran sodium sulfate (DSS) colitis. To characterize the Hedgehog target cell, Gli1-CreERT2-Rosa26-ZsGreen animals were generated, which express ZsGreen in all Hedgehog-responsive cells. These cells were characterized using flow cytometry and immunofluorescence. Loss of Indian Hedgehog from the intestinal epithelium resulted in a rapid increase in expression of inflammation-related genes, accompanied by increased influx of immune cells. Animals with epithelium-specific deletion of Ihh or lacking the Hedgehog receptor Smoothened from Hedgehog target cells were more sensitive to DSS colitis. In contrast, specific deletion of Smoothened in the myeloid compartment did not alter the response to DSS. This suggests that Hedgehog signaling does not repress intestinal immunity through an effect on myeloid cells. Indeed, we found that Hedgehog-responsive cells expressed gp38, smooth muscle actin, and desmin, indicating a fibroblastic nature. Ihh signaling inhibited expression of C-X-C motif chemokine ligand 12 (CXCL12) in fibroblasts in vitro and in vivo, thereby impairing the recruitment of immune cells. We show that epithelium-derived Indian Hedgehog signals exclusively to fibroblasts in the intestine. Loss of Ihh leads to a rapid immune response with up-regulation of fibroblast

Focal adhesion kinase is required for intestinal regeneration and tumorigenesis downstream of Wnt/c-Myc signaling

NARCIS (Netherlands)

Ashton, Gabrielle H.; Morton, Jennifer P.; Myant, Kevin; Phesse, Toby J.; Ridgway, Rachel A.; Marsh, Victoria; Wilkins, Julie A.; Athineos, Dimitris; Muncan, Vanesa; Kemp, Richard; Neufeld, Kristi; Clevers, Hans; Brunton, Valerie; Winton, Douglas J.; Wang, Xiaoyan; Sears, Rosalie C.; Clarke, Alan R.; Frame, Margaret C.; Sansom, Owen J.

2010-01-01

The intestinal epithelium has a remarkable capacity to regenerate after injury and DNA damage. Here, we show that the integrin effector protein Focal Adhesion Kinase (FAK) is dispensable for normal intestinal homeostasis and DNA damage signaling, but is essential for intestinal regeneration

Platelet-activating factor induces TLR4 expression in intestinal epithelial cells: implication for the pathogenesis of necrotizing enterocolitis.

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Antoine Soliman

Full Text Available Necrotizing enterocolitis (NEC is a leading cause of morbidity and mortality in neonatal intensive care units, however its pathogenesis is not completely understood. We have previously shown that platelet activating factor (PAF, bacteria and TLR4 are all important factors in the development of NEC. Given that Toll-like receptors (TLRs are expressed at low levels in enterocytes of the mature gastrointestinal tract, but were shown to be aberrantly over-expressed in enterocytes in experimental NEC, we examined the regulation of TLR4 expression and signaling by PAF in intestinal epithelial cells using human and mouse in vitro cell lines, and the ex vivo rat intestinal loop model. In intestinal epithelial cell (IEC lines, PAF stimulation yielded upregulation of both TLR4 mRNA and protein expression and led to increased IL-8 secretion following stimulation with LPS (in an otherwise LPS minimally responsive cell line. PAF stimulation resulted in increased human TLR4 promoter activation in a dose dependent manner. Western blotting and immunohistochemical analysis showed PAF induced STAT3 phosphorylation and nuclear translocation in IEC, and PAF-induced TLR4 expression was inhibited by STAT3 and NFκB Inhibitors. Our findings provide evidence for a mechanism by which PAF augments inflammation in the intestinal epithelium through abnormal TLR4 upregulation, thereby contributing to the intestinal injury of NEC.

Communication between B-Cells and Microbiota for the Maintenance of Intestinal Homeostasis

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Yuying Liu

2013-10-01

Full Text Available The human intestine is populated with an extremely dense and diverse bacterial community. Commensal bacteria act as an important antigenic stimulus producing the maturation of gut-associated lymphoid tissue (GALT. The production of immunoglobulin (Ig A by B-cells in the GALT is one of the immune responses following intestinal colonization of bacteria. The switch of B-cells from IgM to IgA-producing cells in the Peyer’s patches and neighboring lamina propria proceeds by T-cell-dependent and T-cell-independent mechanisms. Several grams of secretory IgA (SIgA are released into the intestine each day. SIgA serves as a first-line of defense in protecting the intestinal epithelium from enteric toxins and pathogenic microorganisms. SIgA has a capacity to directly quench bacterial virulence factors, influence the composition of the intestinal microbiota, and promote the transportation of antigens across the intestinal epithelium to GALT and down-regulate proinflammatory responses associated with the uptake of highly pathogenic bacteria and potentially allergenic antigens. This review summarizes the reciprocal interactions between intestinal B cells and bacteria, specifically, the formation of IgA in the gut, the role of intestinal IgA in the regulation of bacterial communities and the maintenance of intestinal homeostasis, and the effects of probiotics on IgA levels in the gastrointestinal tract.

Bilateral lesions of suprachiasmatic nuclei affect circadian rhythms in [3H]-thymidine incorporation into deoxyribonucleic acid in mouse intestinal tract, mitotic index of corneal epithelium, and serum corticosterone

International Nuclear Information System (INIS)

Scheving, L.E.; Tsai, T.H.; Powell, E.W.; Pasley, J.N.; Halberg, F.; Dunn, J.

1983-01-01

Investigations into the role of the suprachiasmatic nuclei (SCN) in the coordination of circadian rhythms have presented differing results. Several reports have shown that ablation of the suprachiasmatic nuclei (SCNA) alters the phase and amplitude of rhythms but does not abolish them. The present study investigates the effect of SCNA on the rhythms in cell proliferation in various regions of the intestinal tract as measured by the incorporation of [ 3 H]-thymidine into deoxyribonucleic acid, in the mitotic activity of the corneal epithelium, and in serum corticosterone levels. The study involved mice with verified lesions of the SCN (six to 13 mice per time point) and control groups of both sham-operated and unoperated mice (seven of each per time point). The mice were killed in groups that represented seven time points over a single 24 hr span (3 hr intervals with the 0800 hr sampled both at start and end of the series). The tissues examined were the tongue, esophagus, gastric stomach, and colon for DNA synthesis, the corneal epithelium for mitotic index, and blood serum for corticosterone level. The most consistent result of SCNA was a phase advance in the rhythms in cell proliferation in the tongue, esophagus, gastric stomach, colon, and corneal epithelium. A reduction in rhythm amplitude occurred in the tongue, esophagus, and corneal epithelium; however, there was an amplitude increase for the stomach, colon, and serum corticosterone. The mesor (rhythm-adjusted mean) was increased by SCNA in all tissues except the corneal epithelium. These findings further support the role of the suprachiasmatic nuclear area in the control of rhythms in cell proliferation and corticosterone production, by acting as a ''phase-resetter'' and as a modulator of rhythm amplitude

Effects of fasting and refeeding on intestinal cell proliferation and apoptosis in hammerhead shark (Sphyrna lewini

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Hideya Takahashi

2014-04-01

Full Text Available Objective: To examine the effects of fasting and refeeding on intestinal cell proliferation and apoptosis in an opportunistic predator, hammerhead shark (Sphyrna lewini of elasmobranch fishes which are among the earliest known extant groups of vertebrates to have the valvular intestine typical for the primitive species. Methods: Animals were euthanized after 5-10 d of fasting or feeding, or after 10-day fasting and 5-day refeeding. Intestinal apoptosis and cell proliferation were assessed by using oligonucleotide detection assay, terminal deoxynucleotidyl transferase dUTP nick end labeling staining, and immunohistochemistry of proliferating cells nuclear antigen. Results: Plasma levels of cholesterol and glucose were reduced by fasting. Intestinal apoptosis generally decreased during fasting. Numerous apoptotic cells were observed around the tips of the villi, primarily in the epithelium in the fed sharks, whereas fewer labeled nuclei were detected in the epithelium of fasted sharks. Refeeding returned intestinal apoptosis to the level in the fed sharks. Proliferating cells were observed in the epithelium around the troughs of the villi and greater in number in fed sharks, whereas fewer labeled nuclei were detected in fasted sharks. Conclusions: The cell turnover is modified in both intestinal epithelia of the shark and the murines by fasting/feeding, but in opposite directions. The difference may reflect the feeding ecology of the elasmobranchs, primitive intermittent feeders.

Preliminary study of the effects of Okadaic Acid in the intestinal tract of mouse

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Diego Alberto Fernández

2014-06-01

Our results support the little morphological effect of OA on intestinal cells. However, more interdisciplinary research is needed to obtain precise and reliable data to clarify the effects of OA in the intestinal epithelium and its relation with the diarrhea.

Gut microbiota and probiotics in modulation of epithelium and gut-associated lymphoid tissue function.

Science.gov (United States)

Sanz, Yolanda; De Palma, Giada

2009-01-01

The intestinal tract mucosa is exposed to a vast number of environmental antigens and a large community of commensal bacteria. The mucosal immune system has to provide both protection against pathogens and tolerance to harmless bacteria. Immune homeostasis depends on the interaction of indigenous commensal and transient bacteria (probiotics) with various components of the epithelium and the gut-associated lymphoid tissue. Herein, an update is given of the mechanisms by which the gut microbiota and probiotics are translocated through the epithelium, sensed via pattern-recognition receptors, and activate innate and adaptive immune responses.

Development of Functional Microfold (M Cells from Intestinal Stem Cells in Primary Human Enteroids.

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Joshua D Rouch

Full Text Available Intestinal microfold (M cells are specialized epithelial cells that act as gatekeepers of luminal antigens in the intestinal tract. They play a critical role in the intestinal mucosal immune response through transport of viruses, bacteria and other particles and antigens across the epithelium to immune cells within Peyer's patch regions and other mucosal sites. Recent studies in mice have demonstrated that M cells are generated from Lgr5+ intestinal stem cells (ISCs, and that infection with Salmonella enterica serovar Typhimurium increases M cell formation. However, it is not known whether and how these findings apply to primary human small intestinal epithelium propagated in an in vitro setting.Human intestinal crypts were grown as monolayers with growth factors and treated with recombinant RANKL, and assessed for mRNA transcripts, immunofluorescence and uptake of microparticles and S. Typhimurium.Functional M cells were generated by short-term culture of freshly isolated human intestinal crypts in a dose- and time-dependent fashion. RANKL stimulation of the monolayer cultures caused dramatic induction of the M cell-specific markers, SPIB, and Glycoprotein-2 (GP2 in a process primed by canonical WNT signaling. Confocal microscopy demonstrated a pseudopod phenotype of GP2-positive M cells that preferentially take up microparticles. Furthermore, infection of the M cell-enriched cultures with the M cell-tropic enteric pathogen, S. Typhimurium, led to preferential association of the bacteria with M cells, particularly at lower inoculum sizes. Larger inocula caused rapid induction of M cells.Human intestinal crypts containing ISCs can be cultured and differentiate into an epithelial layer with functional M cells with characteristic morphological and functional properties. This study is the first to demonstrate that M cells can be induced to form from primary human intestinal epithelium, and that S. Typhimurium preferentially infect these cells in an

Requirement of the Epithelium-specific Ets Transcription Factor Spdef for Mucous Gland Cell Function in the Gastric Antrum*

OpenAIRE

Horst, David; Gu, Xuesong; Bhasin, Manoj; Yang, Quanli; Verzi, Michael; Lin, Dongxu; Joseph, Marie; Zhang, Xiaobo; Chen, Wei; Li, Yi-Ping; Shivdasani, Ramesh A.; Libermann, Towia A.

2010-01-01

Mucus-secreting cells of the stomach epithelium provide a protective barrier against damage that might result from bacterial colonization or other stimuli. Impaired barrier function contributes to chronic inflammation and cancer. Knock-out mice for the epithelium-specific transcription factor Spdef (also called Pdef) have defects in terminal differentiation of intestinal and bronchial secretory cells. We sought to determine the physiologic function of Spdef in the stomach, another site of sig...

Loss of the Wnt receptor frizzled 7 in the mouse gastric epithelium is deleterious and triggers rapid repopulation in vivo

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Dustin J. Flanagan

2017-08-01

Full Text Available The gastric epithelium consists of tubular glandular units, each containing several differentiated cell types, and populations of stem cells, which enable the stomach to secrete the acid, mucus and various digestive enzymes required for its function. Very little is known about which cell signalling pathways are required for homeostasis of the gastric epithelium. Many diseases, such as cancer, arise as a result of deregulation of signalling pathways that regulate homeostasis of the diseased organ. Therefore, it is important to understand the biology of how normal conditions are maintained in a tissue to help inform the mechanisms driving disease in that same tissue, and to identify potential points of therapeutic intervention. Wnt signalling regulates several cell functions, including proliferation, differentiation and migration, and plays a crucial role during homeostasis of several tissues, including the intestinal epithelium. Wnt3a is required in the culture medium of gastric organoids, suggesting it is also important for the homeostasis of the gastric epithelium, but this has not been investigated in vivo. Here, we show that the Wnt receptor frizzled 7 (Fzd7, which is required for the homeostasis of the intestine, is expressed in the gastric epithelium and is required for gastric organoid growth. Gastric-specific loss of Fzd7 in the adult gastric epithelium of mice is deleterious and triggers rapid epithelial repopulation, which we believe is the first observation of this novel function for this tissue. Taken together, these data provide functional evidence of a crucial role for Wnt signalling, via the Fzd7 receptor, during homeostasis of the gastric epithelium.

St. John's wort attenuates irinotecan-induced diarrhea via down-regulation of intestinal pro-inflammatory cytokines and inhibition of intestinal epithelial apoptosis

International Nuclear Information System (INIS)

Hu Zeping; Yang Xiaoxia; Chan Suiyung; Xu Anlong; Duan Wei; Zhu Yizhun; Sheu, F.-S.; Boelsterli, Urs Alex; Chan, Eli; Zhang Qiang; Wang, J.-C.; Ee, Pui Lai Rachel; Koh, H.L.; Huang Min; Zhou Shufeng

2006-01-01

Diarrhea is a common dose-limiting toxicity associated with cancer chemotherapy, in particular for drugs such as irinotecan (CPT-11), 5-fluouracil, oxaliplatin, capecitabine and raltitrexed. St. John's wort (Hypericum perforatum, SJW) has anti-inflammatory activity, and our preliminary study in the rat and a pilot study in cancer patients found that treatment of SJW alleviated irinotecan-induced diarrhea. In the present study, we investigated whether SJW modulated various pro-inflammatory cytokines including interleukins (IL-1β, IL-2, IL-6), interferon (IFN-γ) and tumor necrosis factor-α (TNF-α) and intestinal epithelium apoptosis in rats. The rats were treated with irinotecan at 60 mg/kg for 4 days in combination with oral SJW or SJW-free control vehicle at 400 mg/kg for 8 days. Diarrhea, tissue damage, body weight loss, various cytokines including IL-1β, IL-2, IL-6, IFN-γ and TNF-α and intestinal epithelial apoptosis were monitored over 11 days. Our studies demonstrated that combined SJW markedly reduced CPT-11-induced diarrhea and intestinal lesions. The production of pro-inflammatory cytokines such as IL-1β, IFN-γ and TNF-α was significantly up-regulated in intestine. In the mean time, combined SJW significantly suppressed the intestinal epithelial apoptosis induced by CPT-11 over days 5-11. In particular, combination of SJW significantly inhibited the expression of TNF-α mRNA in the intestine over days 5-11. In conclusion, inhibition of pro-inflammatory cytokines and intestinal epithelium apoptosis partly explained the protective effect of SJW against the intestinal toxicities induced by irinotecan. Further studies are warranted to explore the potential for STW as an agent in combination with chemotherapeutic drugs to lower their dose-limiting toxicities

The role of innate signaling in the homeostasis of tolerance and immunity in the intestine.

NARCIS (Netherlands)

Wells, J.; Loonen, L.M.P.; Karczewski, J.

2010-01-01

In the intestine innate recognition of microbes is achieved through pattern recognition receptor (PRR) families expressed in immune cells and different cell lineages of the intestinal epithelium. Toll-like receptor (TLR) and nucleotide-binding and oligomerization domain-like receptor (NLR) families

The food contaminant deoxynivalenol, decreases intestinal barrier permeability and reduces claudin expression

International Nuclear Information System (INIS)

Pinton, Philippe; Nougayrede, Jean-Philippe; Del Rio, Juan-Carlos; Moreno, Carolina; Marin, Daniela E.; Ferrier, Laurent; Bracarense, Ana-Paula; Kolf-Clauw, Martine; Oswald, Isabelle P.

2009-01-01

'The gastrointestinal tract represents the first barrier against food contaminants as well as the first target for these toxicants. Deoxynivalenol (DON) is a mycotoxin that commonly contaminates cereals and causes various toxicological effects. Through consumption of contaminated cereals and cereal products, human and pigs are exposed to this mycotoxin. Using in vitro, ex vivo and in vivo approaches, we investigated the effects of DON on the intestinal epithelium. We demonstrated that, in intestinal epithelial cell lines from porcine (IPEC-1) or human (Caco-2) origin, DON decreases trans-epithelial electrical resistance (TEER) and increases in a time and dose-dependent manner the paracellular permeability to 4 kDa dextran and to pathogenic Escherichia coli across intestinal cell monolayers. In pig explants treated with DON, we also observed an increased permeability of intestinal tissue. These alterations of barrier function were associated with a specific reduction in the expression of claudins, which was also seen in vivo in the jejunum of piglets exposed to DON-contaminated feed. In conclusion, DON alters claudin expression and decreases the barrier function of the intestinal epithelium. Considering that high levels of DON may be present in food or feed, consumption of DON-contaminated food/feed may induce intestinal damage and has consequences for human and animal health.

The Circadian Clock Gene BMAL1 Coordinates Intestinal RegenerationSummary

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Kyle Stokes

2017-07-01

Full Text Available Background & Aims: The gastrointestinal syndrome is an illness of the intestine caused by high levels of radiation. It is characterized by extensive loss of epithelial tissue integrity, which initiates a regenerative response by intestinal stem and precursor cells. The intestine has 24-hour rhythms in many physiological functions that are believed to be outputs of the circadian clock: a molecular system that produces 24-hour rhythms in transcription/translation. Certain gastrointestinal illnesses are worsened when the circadian rhythms are disrupted, but the role of the circadian clock in gastrointestinal regeneration has not been studied. Methods: We tested the timing of regeneration in the mouse intestine during the gastrointestinal syndrome. The role of the circadian clock was tested genetically using the BMAL1 loss of function mouse mutant in vivo, and in vitro using intestinal organoid culture. Results: The proliferation of the intestinal epithelium follows a 24-hour rhythm during the gastrointestinal syndrome. The circadian clock runs in the intestinal epithelium during this pathologic state, and the loss of the core clock gene, BMAL1, disrupts both the circadian clock and rhythmic proliferation. Circadian activity in the intestine involves a rhythmic production of inflammatory cytokines and subsequent rhythmic activation of the JNK stress response pathway. Conclusions: Our results show that a circadian rhythm in inflammation and regeneration occurs during the gastrointestinal syndrome. The study and treatment of radiation-induced illnesses, and other gastrointestinal illnesses, should consider 24-hour timing in physiology and pathology. Keywords: Intestine, Circadian Rhythms, Gastrointestinal Syndrome, TNF, Intestinal Stem Cells

An intestinal Trojan horse for gene delivery.

Science.gov (United States)

Peng, Haisheng; Wang, Chao; Xu, Xiaoyang; Yu, Chenxu; Wang, Qun

2015-03-14

The intestinal epithelium forms an essential element of the mucosal barrier and plays a critical role in the pathophysiological response to different enteric disorders and diseases. As a major enteric dysfunction of the intestinal tract, inflammatory bowel disease is a genetic disease which results from the inappropriate and exaggerated mucosal immune response to the normal constituents in the mucosal microbiota environment. An intestine targeted drug delivery system has unique advantages in the treatment of inflammatory bowel disease. As a new concept in drug delivery, the Trojan horse system with the synergy of nanotechnology and host cells can achieve better therapeutic efficacy in specific diseases. Here, we demonstrated the feasibility of encapsulating DNA-functionalized gold nanoparticles into primary isolated intestinal stem cells to form an intestinal Trojan horse for gene regulation therapy of inflammatory bowel disease. This proof-of-concept intestinal Trojan horse will have a wide variety of applications in the diagnosis and therapy of enteric disorders and diseases.

The impact of non-steroidal anti-inflammatory drugs on the small intestinal epithelium

OpenAIRE

Handa, Osamu; Naito, Yuji; Fukui, Akifumi; Omatsu, Tatsushi; Yoshikawa, Toshikazu

2013-01-01

The small intestine has been called as a dark continent of digestive tract and it had been very difficult to diagnose or treat the disease of small intestine. However recent technological development including video capsule endoscopy or balloon-assisted endoscopy has made us to aware the various diseases of small intestine. By using capsule endoscopy, many researchers reported that more than 70% of patients treated continuously with non-steroidal anti-inflammatory drugs (NSAID) exhibit the mu...

Transport across the choroid plexus epithelium.

Science.gov (United States)

Praetorius, Jeppe; Damkier, Helle Hasager

2017-06-01

The choroid plexus epithelium is a secretory epithelium par excellence. However, this is perhaps not the most prominent reason for the massive interest in this modest-sized tissue residing inside the brain ventricles. Most likely, the dominant reason for extensive studies of the choroid plexus is the identification of this epithelium as the source of the majority of intraventricular cerebrospinal fluid. This finding has direct relevance for studies of diseases and conditions with deranged central fluid volume or ionic balance. While the concept is supported by the vast majority of the literature, the implication of the choroid plexus in secretion of the cerebrospinal fluid was recently challenged once again. Three newer and promising areas of current choroid plexus-related investigations are as follows: 1 ) the choroid plexus epithelium as the source of mediators necessary for central nervous system development, 2 ) the choroid plexus as a route for microorganisms and immune cells into the central nervous system, and 3 ) the choroid plexus as a potential route for drug delivery into the central nervous system, bypassing the blood-brain barrier. Thus, the purpose of this review is to highlight current active areas of research in the choroid plexus physiology and a few matters of continuous controversy. Copyright © 2017 the American Physiological Society.

Preparation and properties of monoclonal antibodies to individual prekeratins of simple rat epithelium

International Nuclear Information System (INIS)

Troyanovskii, S.M.; Krutovskikh, V.A.; Bannikov, G.A.

1986-01-01

The authors study the properties of a series of hybridoma clones producing antibodies to individual prekeratins (PK) from simple types of epithelium. BALB/c mice were immunized with a preparation of intermediate filaments isolated from the mucosa of the rat large intestine. The specificity of the five clones studied was studied by monoautoradiography. For a more detailed study of the specificity of the experimentally obtained antibodies, the authors used the same immunoautoradiographic method to study their reaction with proteins of cells of other types. The authors have obtained monoclonal antibodies to three individual PK of simple types of rat epithelium: PK40, PK49, and PK55

Intestinal spirochetosis and colon diverticulosis Espiroquetose intestinal e diverticulose do cólon

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Marcus Aurelho de Lima

2005-02-01

Full Text Available A case of intestinal spirochetosis in a 62-year-old white male is reported. The condition was characterized by chronic flatulence and episodes of intestinal hemorrhage, in addition to the evidence of hypotonic diverticular disease, with a large number of slender organisms in the colon epithelium and cryptae. Spirochetes were demonstrated by Whartin-Starry stain. The serologic tests for syphilis and HIV were positive. Spirochetosis was treated with penicillin G, and the patient remains free of intestinal complaints 20 months later.Um caso de espiroquetose intestinal é relatado em um homem branco de 62 anos. A condição foi caracterizada por flatulência crônica e episódios de hemorragia intestinal, além da evidência de doença diverticular hipotônica dos cólons, com numerosos organismos filamentosos no epitélio e nas criptas do cólon. Os espiroquetas foram demonstrados pela coloração de Whartin-Starry. Os testes sorológicos para sífilis e HIV foram positivos. A espiroquetose foi tratada com penicilina G e o paciente permanece sem queixas intestinais após 20 meses.

Loss of the Wnt receptor frizzled 7 in the mouse gastric epithelium is deleterious and triggers rapid repopulation in vivo.

Science.gov (United States)

Flanagan, Dustin J; Barker, Nick; Nowell, Cameron; Clevers, Hans; Ernst, Matthias; Phesse, Toby J; Vincan, Elizabeth

2017-08-01

The gastric epithelium consists of tubular glandular units, each containing several differentiated cell types, and populations of stem cells, which enable the stomach to secrete the acid, mucus and various digestive enzymes required for its function. Very little is known about which cell signalling pathways are required for homeostasis of the gastric epithelium. Many diseases, such as cancer, arise as a result of deregulation of signalling pathways that regulate homeostasis of the diseased organ. Therefore, it is important to understand the biology of how normal conditions are maintained in a tissue to help inform the mechanisms driving disease in that same tissue, and to identify potential points of therapeutic intervention. Wnt signalling regulates several cell functions, including proliferation, differentiation and migration, and plays a crucial role during homeostasis of several tissues, including the intestinal epithelium. Wnt3a is required in the culture medium of gastric organoids, suggesting it is also important for the homeostasis of the gastric epithelium, but this has not been investigated in vivo Here, we show that the Wnt receptor frizzled 7 (Fzd7), which is required for the homeostasis of the intestine, is expressed in the gastric epithelium and is required for gastric organoid growth. Gastric-specific loss of Fzd7 in the adult gastric epithelium of mice is deleterious and triggers rapid epithelial repopulation, which we believe is the first observation of this novel function for this tissue. Taken together, these data provide functional evidence of a crucial role for Wnt signalling, via the Fzd7 receptor, during homeostasis of the gastric epithelium. © 2017. Published by The Company of Biologists Ltd.

Distinct Roles for Intestinal Epithelial Cell-Specific Hdac1 and Hdac2 in the Regulation of Murine Intestinal Homeostasis.

Science.gov (United States)

Gonneaud, Alexis; Turgeon, Naomie; Boudreau, François; Perreault, Nathalie; Rivard, Nathalie; Asselin, Claude

2016-02-01

The intestinal epithelium responds to and transmits signals from the microbiota and the mucosal immune system to insure intestinal homeostasis. These interactions are in part conveyed by epigenetic modifications, which respond to environmental changes. Protein acetylation is an epigenetic signal regulated by histone deacetylases, including Hdac1 and Hdac2. We have previously shown that villin-Cre-inducible intestinal epithelial cell (IEC)-specific Hdac1 and Hdac2 deletions disturb intestinal homeostasis. To determine the role of Hdac1 and Hdac2 in the regulation of IEC function and the establishment of the dual knockout phenotype, we have generated villin-Cre murine models expressing one Hdac1 allele without Hdac2, or one Hdac2 allele without Hdac1. We have also investigated the effect of short-term deletion of both genes in naphtoflavone-inducible Ah-Cre and tamoxifen-inducible villin-Cre(ER) mice. Mice with one Hdac1 allele displayed normal tissue architecture, but increased sensitivity to DSS-induced colitis. In contrast, mice with one Hdac2 allele displayed intestinal architecture defects, increased proliferation, decreased goblet cell numbers as opposed to Paneth cells, increased immune cell infiltration associated with fibrosis, and increased sensitivity to DSS-induced colitis. In comparison to dual knockout mice, intermediary activation of Notch, mTOR, and Stat3 signaling pathways was observed. While villin-Cre(ER) Hdac1 and Hdac2 deletions led to an impaired epithelium and differentiation defects, Ah-Cre-mediated deletion resulted in blunted proliferation associated with the induction of a DNA damage response. Our results suggest that IEC determination and intestinal homeostasis are highly dependent on Hdac1 and Hdac2 activity levels, and that changes in the IEC acetylome may alter the mucosal environment. © 2015 Wiley Periodicals, Inc.

Organ Culture as a Model System for Studies on Enterotoxin Interactions with the Intestinal Epithelium

DEFF Research Database (Denmark)

Lorenzen, Ulver Spangsberg; Hansen, Gert H; Danielsen, E Michael

2015-01-01

Studies on bacterial enterotoxin-epithelium interactions require model systems capable of mimicking the events occurring at the molecular and cellular levels during intoxication. In this chapter, we describe organ culture as an often neglected alternative to whole-animal experiments or enterocyte......-like cell lines. Like cell culture, organ culture is versatile and suitable for studying rapidly occurring events, such as enterotoxin binding and uptake. In addition, it is advantageous in offering an epithelium with more authentic permeability/barrier properties than any cell line, as well...

Intestinal immune response to chicken Coccidiosis in the context of Th1 and Th17 response

Science.gov (United States)

Coccidiosis is one of the most economically important diseases of the chickens caused by several different Eimeria spp. The primary target tissue of Eimeria parasites is the intestinal mucosa and coccidiosis infection destroys intestinal epithelium resulting in nutrient malabsorption, body weight lo...

JAK/STAT-1 Signaling Is Required for Reserve Intestinal Stem Cell Activation during Intestinal Regeneration Following Acute Inflammation

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Camilla A. Richmond

2018-01-01

Full Text Available The intestinal epithelium serves as an essential barrier to the outside world and is maintained by functionally distinct populations of rapidly cycling intestinal stem cells (CBC ISCs and slowly cycling, reserve ISCs (r-ISCs. Because disruptions in the epithelial barrier can result from pathological activation of the immune system, we sought to investigate the impact of inflammation on ISC behavior during the regenerative response. In a murine model of αCD3 antibody-induced small-intestinal inflammation, r-ISCs proved highly resistant to injury, while CBC ISCs underwent apoptosis. Moreover, r-ISCs were induced to proliferate and functionally contribute to intestinal regeneration. Further analysis revealed that the inflammatory cytokines interferon gamma and tumor necrosis factor alpha led to r-ISC activation in enteroid culture, which could be blocked by the JAK/STAT inhibitor, tofacitinib. These results highlight an important role for r-ISCs in response to acute intestinal inflammation and show that JAK/STAT-1 signaling is required for the r-ISC regenerative response.

Foxl1-Expressing Mesenchymal Cells Constitute the Intestinal Stem Cell NicheSummary

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Reina Aoki

2016-03-01

Full Text Available Background & Aims: Intestinal epithelial stem cells that express leucine-rich repeat-containing G-protein coupled receptor 5 (Lgr5 and/or B cell specific Moloney murine leukemia virus integration site 1 (Bmi1 continuously replicate and generate differentiated cells throughout life. Previously, Paneth cells were suggested to constitute an epithelium-intrinsic niche that regulates the behavior of these stem cells. However, ablating Paneth cells has no effect on the maintenance of functional stem cells. Here, we show definitively that a small subset of mesenchymal subepithelial cells expressing the winged-helix transcription factor forkhead box l1 (Foxl1 are a critical component of the intestinal stem cell niche. Methods: We genetically ablated Foxl1+ mesenchymal cells in adult mice using 2 separate models by expressing either the human or simian diphtheria toxin receptor under Foxl1 promoter control. Conclusions: Killing Foxl1+ cells by diphtheria toxin administration led to an abrupt cessation of proliferation of both epithelial stem- and transit-amplifying progenitor cell populations that was associated with a loss of active Wnt signaling to the intestinal epithelium. Therefore, Foxl1-expressing mesenchymal cells constitute the fundamental niche for intestinal stem cells. Keywords: Intestinal Stem Cell Niche, Wnt, Mesenchyme

Phagocytosis of Giardia muris by macrophages in Peyer's patch epithelium in mice.

Science.gov (United States)

Owen, R L; Allen, C L; Stevens, D P

1981-08-01

No mechanism for the initiation of immunological clearance of Giardia from the mammalian intestinal tract has been identified. In normal and nude mice experimentally infected with G. muris, we examined antigen-sampling epithelium over Peyer's patch follicles by electron microscopy for evidence of interaction between G. muris and lymphoid cells. Invading G. muris were found in the epithelium near dying or desquamating columnar cells. Macrophages beneath the basal lamina extended pseudopods into the epithelium, trapping invading G. muris and enclosing them in phagolysosomes. In normal mice, which clear G. muris in 4 to 6 weeks, macrophages containing digested G. muris were surrounded by rosettes of lymphoblasts in the epithelium. In nude mice deficient in lymphocytes, there was apparent hyperplasia of macrophages, which filled the follicle domes, resulting in more frequent entrapment of G. muris but no contact between macrophages and lymphoblasts in the epithelium. In nude mice, which require 6 months to control G. muris infection, lymphoblast contact with macrophages containing distinctive microtubular remnants of G. muris was only identified in the follicle dome. This close physical association of lymphoblasts and macrophages containing G. muris remnants suggests that this macrophage activity represents intraepithelial antigen processing as well as a defense against the effects of the uncontrolled entrance of microorganisms and other antigenic particles into Peyer's patch lymphoid follicles.

IL-33 activates tumor stroma to promote intestinal polyposis.

Science.gov (United States)

Maywald, Rebecca L; Doerner, Stephanie K; Pastorelli, Luca; De Salvo, Carlo; Benton, Susan M; Dawson, Emily P; Lanza, Denise G; Berger, Nathan A; Markowitz, Sanford D; Lenz, Heinz-Josef; Nadeau, Joseph H; Pizarro, Theresa T; Heaney, Jason D

2015-05-12

Tumor epithelial cells develop within a microenvironment consisting of extracellular matrix, growth factors, and cytokines produced by nonepithelial stromal cells. In response to paracrine signals from tumor epithelia, stromal cells modify the microenvironment to promote tumor growth and metastasis. Here, we identify interleukin 33 (IL-33) as a regulator of tumor stromal cell activation and mediator of intestinal polyposis. In human colorectal cancer, IL-33 expression was induced in the tumor epithelium of adenomas and carcinomas, and expression of the IL-33 receptor, IL1RL1 (also referred to as IL1-R4 or ST2), localized predominantly to the stroma of adenoma and both the stroma and epithelium of carcinoma. Genetic and antibody abrogation of responsiveness to IL-33 in the Apc(Min/+) mouse model of intestinal tumorigenesis inhibited proliferation, induced apoptosis, and suppressed angiogenesis in adenomatous polyps, which reduced both tumor number and size. Similar to human adenomas, IL-33 expression localized to tumor epithelial cells and expression of IL1RL1 associated with two stromal cell types, subepithelial myofibroblasts and mast cells, in Apc(Min/+) polyps. In vitro, IL-33 stimulation of human subepithelial myofibroblasts induced the expression of extracellular matrix components and growth factors associated with intestinal tumor progression. IL-33 deficiency reduced mast cell accumulation in Apc(Min/+) polyps and suppressed the expression of mast cell-derived proteases and cytokines known to promote polyposis. Based on these findings, we propose that IL-33 derived from the tumor epithelium promotes polyposis through the coordinated activation of stromal cells and the formation of a protumorigenic microenvironment.

Overview of Current Concepts in Gastric Intestinal Metaplasia and Gastric Cancer.

Science.gov (United States)

Jencks, David S; Adam, Jason D; Borum, Marie L; Koh, Joyce M; Stephen, Sindu; Doman, David B

2018-02-01

Gastric intestinal metaplasia is a precancerous change of the mucosa of the stomach with intestinal epithelium, and is associated with an increased risk of dysplasia and cancer. The pathogenesis to gastric cancer is proposed by the Correa hypothesis as the transition from normal gastric epithelium to invasive cancer via inflammation followed by intramucosal cancer and invasion. Multiple risk factors have been associated with the development of gastric intestinal metaplasia interplay, including Helicobacter pylori infection and associated genomics, host genetic factors, environmental milieu, rheumatologic disorders, diet, and intestinal microbiota. Globally, screening guidelines have been established in countries with high incidence. In the United States, no such guidelines have been developed due to lower, albeit increasing, incidence. The American Society for Gastrointestinal Endoscopy recommends a case-by-case patient assessment based upon epidemiology, genetics, and environmental risk factors. Studies have examined the use of a serologic biopsy to stratify risk based upon factors such as H pylori status and virulence factors, along with serologic markers of chronic inflammation including pepsinogen I, pepsinogen II, and gastrin. High-risk patients may then be advised to undergo endoscopic evaluation with mapping biopsies from the antrum (greater curvature, lesser curvature), incisura angularis, and corpus (greater curvature, lesser curvature). Surveillance guidelines have not been firmly established for patients with known gastric intestinal metaplasia, but include repeat endoscopy at intervals according to the histologic risk for malignant transformation.

The Homeodomain Transcription Factor Cdx1 Does Not Behave as an Oncogene in Normal Mouse Intestine

Directory of Open Access Journals (Sweden)

Mary Ann S. Crissey

2008-01-01

Full Text Available The Caudal-related homeobox genes Cdx1 and Cdx2 are intestine-specific transcription factors that regulate differentiation of intestinal cell types. Previously, we have shown Cdx1 to be antiproliferative and to promote cell differentiation. However, other studies have suggested that Cdx1 may be an oncogene. To test for oncogenic behavior, we used the murine villin promoter to ectopically express Cdx1 in the small intestinal villi and colonic surface epithelium. No changes in intestinal architecture, cell differentiation, or lineage selection were observed with expression of the transgene. Classic oncogenes enhance proliferation and induce tumors when ectopically expressed. However, the Cdx1 transgene neither altered intestinal proliferation nor induced spontaneous intestinal tumors. In a murine model for colitis-associated cancer, the Cdx1 transgene decreased, rather than increased, the number of adenomas that developed. In the polyps, the expression of the endogenous and the transgenic Cdx1 proteins was largely absent, whereas endogenous Villin expression was retained. This suggests that transgene silencing was specific and not due to a general Villin inactivation. In conclusion, neither the ectopic expression of Cdx1 was associated with changes in intestinal cell proliferation or differentiation nor was there increased intestinal cancer susceptibility. Our results therefore suggest that Cdx1 is not an oncogene in normal intestinal epithelium.

Epithelium

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The term "epithelium" refers to layers of cells that line hollow organs and glands. It is also those cells that make ... Kierszenbaum AL, Tres LL. Epithelium. In: Kierszenbaum AL, Tres LL, ... to Pathology . 4th ed. Philadelphia, PA: Elsevier Saunders; ...

Breakdown of mucin as barrier to digestive enzymes in the ischemic rat small intestine.

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Marisol Chang

Full Text Available Loss of integrity of the epithelial/mucosal barrier in the small intestine has been associated with different pathologies that originate and/or develop in the gastrointestinal tract. We showed recently that mucin, the main protein in the mucus layer, is disrupted during early periods of intestinal ischemia. This event is accompanied by entry of pancreatic digestive enzymes into the intestinal wall. We hypothesize that the mucin-containing mucus layer is the main barrier preventing digestive enzymes from contacting the epithelium. Mucin breakdown may render the epithelium accessible to pancreatic enzymes, causing its disruption and increased permeability. The objective of this study was to investigate the role of mucin as a protection for epithelial integrity and function. A rat model of 30 min splanchnic arterial occlusion (SAO was used to study the degradation of two mucin isoforms (mucin 2 and 13 and two epithelial membrane proteins (E-cadherin and toll-like receptor 4, TLR4. In addition, the role of digestive enzymes in mucin breakdown was assessed in this model by luminal inhibition with acarbose, tranexamic acid, or nafamostat mesilate. Furthermore, the protective effect of the mucin layer against trypsin-mediated disruption of the intestinal epithelium was studied in vitro. Rats after SAO showed degradation of mucin 2 and fragmentation of mucin 13, which was not prevented by protease inhibition. Mucin breakdown was accompanied by increased intestinal permeability to FITC-dextran as well as degradation of E-cadherin and TLR4. Addition of mucin to intestinal epithelial cells in vitro protected against trypsin-mediated degradation of E-cadherin and TLR4 and reduced permeability of FITC-dextran across the monolayer. These results indicate that mucin plays an important role in the preservation of the mucosal barrier and that ischemia but not digestive enzymes disturbs mucin integrity, while digestive enzymes actively mediate epithelial cell

Intestinal Colonization Dynamics of Vibrio cholerae.

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Salvador Almagro-Moreno

2015-05-01

Full Text Available To cause the diarrheal disease cholera, Vibrio cholerae must effectively colonize the small intestine. In order to do so, the bacterium needs to successfully travel through the stomach and withstand the presence of agents such as bile and antimicrobial peptides in the intestinal lumen and mucus. The bacterial cells penetrate the viscous mucus layer covering the epithelium and attach and proliferate on its surface. In this review, we discuss recent developments and known aspects of the early stages of V. cholerae intestinal colonization and highlight areas that remain to be fully understood. We propose mechanisms and postulate a model that covers some of the steps that are required in order for the bacterium to efficiently colonize the human host. A deeper understanding of the colonization dynamics of V. cholerae and other intestinal pathogens will provide us with a variety of novel targets and strategies to avoid the diseases caused by these organisms.

The intestinal microenvironment in sepsis.

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Fay, Katherine T; Ford, Mandy L; Coopersmith, Craig M

2017-10-01

The gastrointestinal tract has long been hypothesized to function as "the motor" of multiple organ dysfunction syndrome. The gastrointestinal microenvironment is comprised of a single cell layer epithelia, a local immune system, and the microbiome. These three components of the intestine together play a crucial role in maintaining homeostasis during times of health. However, the gastrointestinal microenvironment is perturbed during sepsis, resulting in pathologic changes that drive both local and distant injury. In this review, we seek to characterize the relationship between the epithelium, gastrointestinal lymphocytes, and commensal bacteria during basal and pathologic conditions and how the intestinal microenvironment may be targeted for therapeutic gain in septic patients. Published by Elsevier B.V.

Cdx1 and c-Myc foster the initiation of transdifferentiation of the normal esophageal squamous epithelium toward Barrett's esophagus.

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Douglas B Stairs

Full Text Available Barrett's esophagus is a premalignant condition whereby the normal stratified squamous esophageal epithelium undergoes a transdifferentiation program resulting in a simple columnar epithelium reminiscent of the small intestine. These changes are typically associated with the stratified squamous epithelium chronically exposed to acid and bile salts as a result of gastroesophageal reflux disease (GERD. Despite this well-defined epidemiologic association between acid reflux and Barrett's esophagus, the genetic changes that induce this transdifferentiation process in esophageal keratinocytes have remained undefined.To begin to identify the genetic changes responsible for transdifferentiaiton in Barrett's esophagus, we performed a microarray analysis of normal esophageal, Barrett's esophagus and small intestinal biopsy specimens to identify candidate signaling pathways and transcription factors that may be involved. Through this screen we identified the Cdx1 homeodomain transcription factor and the c-myc pathway as possible candidates. Cdx1 and c-myc were then tested for their ability to induce transdifferentiation in immortalized human esophageal keratinocytes using organotypic culturing methods. Analyses of these cultures reveal that c-myc and cdx1 cooperate to induce mucin production and changes in keratin expression that are observed in the epithelium of Barrett's esophagus.These data demonstrate the ability of Cdx1 and c-myc to initiate the earliest stages of transdifferentiation of esophageal keratinocytes toward a cell fate characteristic of Barrett's esophagus.

Immune and genetic gardening of the intestinal microbiome

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Jacobs, Jonathan P.; Braun, Jonathan

2014-01-01

The mucosal immune system – consisting of adaptive and innate immune cells as well as the epithelium – is profoundly influenced by its microbial environment. There is now growing evidence that the converse is also true, that the immune system shapes the composition of the intestinal microbiome. During conditions of health, this bidirectional interaction achieves a homeostasis in which inappropriate immune responses to nonpathogenic microbes are averted and immune activity suppresses blooms of potentially pathogenic microbes (pathobionts). Genetic alteration in immune/epithelial function can affect host gardening of the intestinal microbiome, contributing to the diversity of intestinal microbiota within a population and in some cases allowing for unfavorable microbial ecologies (dysbiosis) that confer disease susceptibility. PMID:24613921

Direct Activation of Amidohydrolase Domain-Containing 1 Gene by Thyroid Hormone Implicates a Role in the Formation of Adult Intestinal Stem Cells During Xenopus Metamorphosis.

Science.gov (United States)

Okada, Morihiro; Miller, Thomas C; Fu, Liezhen; Shi, Yun-Bo

2015-09-01

The T3-dependent anuran metamorphosis resembles postembryonic development in mammals, the period around birth when plasma T3 levels peak. In particular, the remodeling of the intestine during metamorphosis mimics neonatal intestinal maturation in mammals when the adult intestinal epithelial self-renewing system is established. We have been using intestinal metamorphosis to investigate how the organ-specific adult stem cells are formed during vertebrate development. Early studies in Xenopus laevis have shown that this process involves complete degeneration of the larval epithelium and de novo formation of adult stem cells. A tissue-specific microarray analysis of intestinal gene expression during Xenopus laevis metamorphosis has identified a number of candidate stem cell genes. Here we have carried out detailed analyses of one such gene, amidohydrolase domain containing 1 (AMDHD1) gene, which encodes an enzyme in the histidine catabolic pathway. We show that AMDHD1 is exclusively expressed in the proliferating adult epithelial stem cells during metamorphosis with little expression in other intestinal tissues. We further provide evidence that T3 activates AMDHD1 gene expression directly at the transcription level through T3 receptor binding to the AMDHD1 gene in the intestine. In addition, we have reported earlier that histidine ammonia-lyase gene, another gene in histidine catabolic pathway, is similarly regulated by T3 in the intestine. These results together suggest that histidine catabolism plays a critical role in the formation and/or proliferation of adult intestinal stem cells during metamorphosis.

Effect of ochratoxin A on the intestinal mucosa and mucosa-associated lymphoid tissues in broiler chickens.

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Solcan, Carmen; Pavel, Geta; Floristean, Viorel Cezar; Chiriac, Ioan Sorin Beschea; Şlencu, Bogdan Gabriel; Solcan, Gheorghe

2015-03-01

The immunotoxic effect of ochratoxin A (OTA) on the intestinal mucosa-associated lymphoid tissue and its cytotoxic action on the intestinal epithelium were studied in broiler chickens experimentally treated with the toxin. From the 7th day of life, 80 male broiler chickens (Ross 308) were randomly divided into four groups of 20 birds each. The three experimental groups (E1-3) were treated with OTA for 28 days (E1: 50 μg/kg body weight [bw]/day; E2: 20 μg/kg bw/day; E3: 1 μg/kg bw/day) and the fourth group served as control. Histological examination of the intestinal mucosa and immunohistochemical staining for identification of CD4+, CD8+, TCR1 and TCR2 lymphocytes in the duodenum, jejunum and ileocaecal junction were performed, and CD4+/CD8+ and TCR1/TCR2 ratios were calculated. OTA toxicity resulted in decreased body weight gain, poorer feed conversion ratio, lower leukocyte and lymphocyte count, and altered intestinal mucosa architecture. After 14 days of exposure to OTA, immunohistochemistry showed a significant reduction of the lymphocyte population in the intestinal epithelium and the lamina propria. After 28 days of exposure, an increase in the CD4+ and CD8+ values in both the duodenum and jejunum of chickens in Groups E1 and E2 was observed, but the TCR1 and TCR2 lymphocyte counts showed a significant reduction. No significant changes were observed in Group E3. The results indicate that OTA induced a decrease in leukocyte and lymphocyte counts and was cytotoxic to the intestinal epithelium and the mucosa-associated lymphoid tissue, altering the intestinal barrier and increasing susceptibility to various associated diseases.

Transformation of intestinal stem cells into gastric stem cells on loss of transcription factor Cdx2

NARCIS (Netherlands)

Simmini, Salvatore; Bialecka, Monika; Huch, Meritxell; Kester, Lennart; van de Wetering, Marc; Sato, Toshiro; Beck, Felix; van Oudenaarden, Alexander; Clevers, Hans; Deschamps, Jacqueline

2014-01-01

The endodermal lining of the adult gastro-intestinal tract harbours stem cells that are responsible for the day-to-day regeneration of the epithelium. Stem cells residing in the pyloric glands of the stomach and in the small intestinal crypts differ in their differentiation programme and in the gene

Stem cell self-renewal in intestinal crypt

International Nuclear Information System (INIS)

Simons, Benjamin D.; Clevers, Hans

2011-01-01

As a rapidly cycling tissue capable of fast repair and regeneration, the intestinal epithelium has emerged as a favored model system to explore the principles of adult stem cell biology. However, until recently, the identity and characteristics of the stem cell population in both the small intestine and colon has remained the subject of debate. Recent studies based on targeted lineage tracing strategies, combined with the development of an organotypic culture system, have identified the crypt base columnar cell as the intestinal stem cell, and have unveiled the strategy by which the balance between proliferation and differentiation is maintained. These results show that intestinal stem cells operate in a dynamic environment in which frequent and stochastic stem cell loss is compensated by the proliferation of neighboring stem cells. We review the basis of these experimental findings and the insights they offer into the mechanisms of homeostatic stem cell regulation.

Mucosal innate immune cells regulate both gut homeostasis and intestinal inflammation.

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Kurashima, Yosuke; Goto, Yoshiyuki; Kiyono, Hiroshi

2013-12-01

Continuous exposure of intestinal mucosal surfaces to diverse microorganisms and their metabolites reflects the biological necessity for a multifaceted, integrated epithelial and immune cell-mediated regulatory system. The development and function of the host cells responsible for the barrier function of the intestinal surface (e.g., M cells, Paneth cells, goblet cells, and columnar epithelial cells) are strictly regulated through both positive and negative stimulation by the luminal microbiota. Stimulation by damage-associated molecular patterns and commensal bacteria-derived microbe-associated molecular patterns provokes the assembly of inflammasomes, which are involved in maintaining the integrity of the intestinal epithelium. Mucosal immune cells located beneath the epithelium play critical roles in regulating both the mucosal barrier and the relative composition of the luminal microbiota. Innate lymphoid cells and mast cells, in particular, orchestrate the mucosal regulatory system to create a mutually beneficial environment for both the host and the microbiota. Disruption of mucosal homeostasis causes intestinal inflammation such as that seen in inflammatory bowel disease. Here, we review the recent research on the biological interplay among the luminal microbiota, epithelial cells, and mucosal innate immune cells in both healthy and pathological conditions. © 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim.

Intestinal cholesterol secretion : future clinical implications

NARCIS (Netherlands)

Jakulj, L.; Besseling, J.; Stroes, E. S. G.; Groen, A. K.

2013-01-01

Together with the liver, the intestine serves as a homeostatic organ in cholesterol metabolism. Recent evidence has substantiated the pivotal role of the intestine in reverse cholesterol transport (RCT). RCT is a fundamental antiatherogenic pathway, mediating the removal of cholesterol from tissues

Intestinal cholesterol secretion: future clinical implications

NARCIS (Netherlands)

Jakulj, L.; Besseling, J.; Stroes, E. S. G.; Groen, A. K.

2013-01-01

Together with the liver, the intestine serves as a homeostatic organ in cholesterol metabolism. Recent evidence has substantiated the pivotal role of the intestine in reverse cholesterol transport (RCT). RCT is a fundamental antiatherogenic pathway, mediating the removal of cholesterol from tissues

Indian Hedgehog Suppresses a Stromal Cell–Driven Intestinal Immune Response

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B. Florien Westendorp

2018-01-01

Conclusions: We show that epithelium-derived Indian Hedgehog signals exclusively to fibroblasts in the intestine. Loss of Ihh leads to a rapid immune response with up-regulation of fibroblast-derived CXCL12, and migration of immune cells into the lamina propria.

Indian Hedgehog Suppresses a Stromal Cell-Driven Intestinal Immune Response

NARCIS (Netherlands)

Westendorp, B. Florien; Büller, Nikè V. J. A.; Karpus, Olga N.; van Dop, Willemijn A.; Koster, Jan; Versteeg, Rogier; Koelink, Pim J.; Snel, Clinton Y.; Meisner, Sander; Roelofs, Joris J. T. H.; Uhmann, Anja; Ver Loren van Themaat, Emiel; Heijmans, Jarom; Hahn, Heidi; Muncan, Vanesa; Wildenberg, Manon E.; van den Brink, Gijs R.

2018-01-01

Upon intestinal epithelial damage a complex wound healing response is initiated to restore epithelial integrity and defend against pathogenic invasion. Epithelium-derived Indian Hedgehog (Ihh) functions as a critical sensor in this process. Signaling occurs in a paracrine manner because the receptor

The Homeodomain Transcription Factor Cdx1 Does Not Behave as an Oncogene in Normal Mouse Intestine1

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Crissey, Mary Ann S; Guo, Rong-Jun; Fogt, Franz; Li, Hong; Katz, Jonathan P; Silberg, Debra G; Suh, Eun Ran; Lynch, John P

2008-01-01

The Caudal-related homeobox genes Cdx1 and Cdx2 are intestine-specific transcription factors that regulate differentiation of intestinal cell types. Previously, we have shown Cdx1 to be antiproliferative and to promote cell differentiation. However, other studies have suggested that Cdx1 may be an oncogene. To test for oncogenic behavior, we used the murine villin promoter to ectopically express Cdx1 in the small intestinal villi and colonic surface epithelium. No changes in intestinal architecture, cell differentiation, or lineage selection were observed with expression of the transgene. Classic oncogenes enhance proliferation and induce tumors when ectopically expressed. However, the Cdx1 transgene neither altered intestinal proliferation nor induced spontaneous intestinal tumors. In a murine model for colitis-associated cancer, the Cdx1 transgene decreased, rather than increased, the number of adenomas that developed. In the polyps, the expression of the endogenous and the transgenic Cdx1 proteins was largely absent, whereas endogenous Villin expression was retained. This suggests that transgene silencing was specific and not due to a general Villin inactivation. In conclusion, neither the ectopic expression of Cdx1 was associated with changes in intestinal cell proliferation or differentiation nor was there increased intestinal cancer susceptibility. Our results therefore suggest that Cdx1 is not an oncogene in normal intestinal epithelium. PMID:18231635

Culture of human intestinal epithelial cell using the dissociating enzyme thermolysin and endothelin-3

OpenAIRE

Liu, Z.; Zhang, P.; Zhou, Y.; Qin, H.; Shen, T.

2010-01-01

Epithelium, a highly dynamic system, plays a key role in the homeostasis of the intestine. However, thus far a human intestinal epithelial cell line has not been established in many countries. Fetal tissue was selected to generate viable cell cultures for its sterile condition, effective generation, and differentiated character. The purpose of the present study was to culture human intestinal epithelial cells by a relatively simple method. Thermolysin was added to improve the yield of epithel...

Effect of zinc treatment on intestinal motility in experimentally ...

African Journals Online (AJOL)

olayemitoyin

4Department of Physiology, College of Medicine, University of Ibadan, Ibadan, Nigeria. Summary: Zinc ... regeneration of the intestinal epithelium, increase the ... cells (Berni et al., 2005). ... The student t-test was used to ... faeces after 24 hours of diarrhea induction and drug .... the gastrointestinal relaxing effects of the stem.

Endocrine regulation of ion transport in the avian lower intestine

DEFF Research Database (Denmark)

Laverty, Gary; Elbrønd, Vibeke Sødring; Árnason, Sighvatur S.

2006-01-01

The lower intestine (colon and coprodeum) of the domestic fowl maintains a very active, transporting epithelium, with a microvillus brush border, columnar epithelial cells, and a variety of transport systems. The colon of normal or high salt-acclimated hens expresses sodium-linked glucose and amino...

Identification of Aging-Associated Gene Expression Signatures That Precede Intestinal Tumorigenesis.

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Yoshihisa Okuchi

Full Text Available Aging-associated alterations of cellular functions have been implicated in various disorders including cancers. Due to difficulties in identifying aging cells in living tissues, most studies have focused on aging-associated changes in whole tissues or certain cell pools. Thus, it remains unclear what kinds of alterations accumulate in each cell during aging. While analyzing several mouse lines expressing fluorescent proteins (FPs, we found that expression of FPs is gradually silenced in the intestinal epithelium during aging in units of single crypt composed of clonal stem cell progeny. The cells with low FP expression retained the wild-type Apc allele and the tissues composed of them did not exhibit any histological abnormality. Notably, the silencing of FPs was also observed in intestinal adenomas and the surrounding normal mucosae of Apc-mutant mice, and mediated by DNA methylation of the upstream promoter. Our genome-wide analysis then showed that the silencing of FPs reflects specific gene expression alterations during aging, and that these alterations occur in not only mouse adenomas but also human sporadic and hereditary (familial adenomatous polyposis adenomas. Importantly, pharmacological inhibition of DNA methylation, which suppresses adenoma development in Apc-mutant mice, reverted the aging-associated silencing of FPs and gene expression alterations. These results identify aging-associated gene expression signatures that are heterogeneously induced by DNA methylation and precede intestinal tumorigenesis triggered by Apc inactivation, and suggest that pharmacological inhibition of the signature genes could be a novel strategy for the prevention and treatment of intestinal tumors.

Overview of Current Concepts in Gastric Intestinal Metaplasia and Gastric Cancer

Science.gov (United States)

Adam, Jason D.; Borum, Marie L.; Koh, Joyce M.; Stephen, Sindu

2018-01-01

Gastric intestinal metaplasia is a precancerous change of the mucosa of the stomach with intestinal epithelium, and is associated with an increased risk of dysplasia and cancer. The pathogenesis to gastric cancer is proposed by the Correa hypothesis as the transition from normal gastric epithelium to invasive cancer via inflammation followed by intramucosal cancer and invasion. Multiple risk factors have been associated with the development of gastric intestinal metaplasia interplay, including Helicobacter pylori infection and associated genomics, host genetic factors, environmental milieu, rheumatologic disorders, diet, and intestinal microbiota. Globally, screening guidelines have been established in countries with high incidence. In the United States, no such guidelines have been developed due to lower, albeit increasing, incidence. The American Society for Gastrointestinal Endoscopy recommends a case-by-case patient assessment based upon epidemiology, genetics, and environmental risk factors. Studies have examined the use of a serologic biopsy to stratify risk based upon factors such as H pylori status and virulence factors, along with serologic markers of chronic inflammation including pepsinogen I, pepsinogen II, and gastrin. High-risk patients may then be advised to undergo endoscopic evaluation with mapping biopsies from the antrum (greater curvature, lesser curvature), incisura angularis, and corpus (greater curvature, lesser curvature). Surveillance guidelines have not been firmly established for patients with known gastric intestinal metaplasia, but include repeat endoscopy at intervals according to the histologic risk for malignant transformation. PMID:29606921

Plasticity of intestinal epithelial cells in regeneration and cancer

NARCIS (Netherlands)

Tetteh, Paul W.

2015-01-01

Cellular plasticity refers to the ability of a cell to change its fate or identity in response to external or intrinsic factors. Regeneration of the intestinal epithelium after injury is driven mainly by plasticity of crypt stem cells that can rapidly divide to replace all the lost cells. Stem cell

Metabolism of all-trans-retinoic acid and all-trans-retinyl acetate. Demonstration of common physiological metabolites in rat small intestinal mucosa and circulation

International Nuclear Information System (INIS)

Cullum, M.E.; Zile, M.H.

1985-01-01

The kinetics and metabolism of physiological doses of all-trans-retinoic acid were examined in blood and small intestinal mucosa of vitamin A-depleted rats. A major portion of intrajugularly injected retinoic acid is rapidly (within 2 min) sequestered by tissues; subsequently 13-cis-retinoic acid and polar metabolites are released into circulation. All-trans-retinoic acid appears in small intestinal epithelium within 2 min after dosing and is the major radioactive compound there for at least 2 h. Retinoyl glucuronide and 13-cis-retinoic acid are early metabolites of all-trans-retinoic acid in the small intestine of bile duct-cannulated rats. Retinoyl glucuronide, the major metabolite of retinoic acid intestinal epithelium, in contrast to other polar metabolites, was not detected in circulation. An examination of [ 3 H]retinyl acetate metabolites under steady state conditions in vitamin A-repleted rats demonstrates the occurrence of all-trans-retinoic acid and 13-cis-retinoic acid in circulation and in intestinal epithelium, in a pattern similar to that found after injection of retinoic acid into vitamin A-depleted rats. These data establish that all-trans-retinoic acid, 13-cis-retinoic acid, and retinoyl glucuronide are physiological metabolites of vitamin A in target tissues, and therefore are important candidates as mediators of the biological effect of the vitamin

Spontaneous and x-irradiation induced carcinomas of small intestine in Wistar-Furth rats

Energy Technology Data Exchange (ETDEWEB)

Maeura, Y; Kosaki, G; Kitamura, H [Osaka Univ. (Japan). Faculty of Medicine; Nagatomo, T

1980-04-01

Spontaneous carcinoma of the small intestine in Wistar-Furth (WF) rats and carcinoma of the small intestine induced by local x-ray irradiation to the abdomen of WF rats without carcinoma were observed, and x-ray sensitivity of the small intestine mucosa was reported. Out of 19 rats with spontaneous carcinoma of the small intestine, 18 also had carcinoma of the colon, and 4 also had gastric cancer. They already had spontaneous carcinoma of the small intestine within 2 weeks after their birth, and the ratio of female and male was 13 : 6. Histological type of this carcinoma in all 19 rats was highly differentiated adenocarcinoma, and small intestine epithelium around carcinoma presented atypical epithelium. As to mice without carcinoma, x-ray, 1,000 R, 1,500 R, and 2,000 R, was irradiated to the abdomen of Sprague-Dawley (SD) and WF rats. In the irradiation with 1,000 R, carcinogenesis was not found in rats of both strains. In the irradiation with 1,500 R, carcinogenesis was hardly found, but in the irradiation with 2,000 R, carcinoma of small intestine occurred in 5 of 17 rats 15 weeks after the irradiation, 9 of 19 rats 25 weeks after the irradiation, and 9 of 14 rats 35 weeks after the irradiation. Histological type of carcinoma in irradiated rats was highly differentiated adenocarcinoma. The incidence of carcinoma in irradiated rats was higher in WF rats than SD rats through the course after the irradiation, which suggested that x-ray sensitivity of WF rats was higher than that of SD rats. Therefore, carcinoma of the small intestine in irradiated mice seemed to be induced by x-ray.

Innate Lymphoid Cells in Intestinal Inflammation

Science.gov (United States)

Geremia, Alessandra; Arancibia-Cárcamo, Carolina V.

2017-01-01

Inflammatory bowel disease (IBD) is a chronic inflammatory disorder of the intestine that encompasses Crohn’s disease (CD) and ulcerative colitis. The cause of IBD is unknown, but the evidence suggests that an aberrant immune response toward the commensal bacterial flora is responsible for disease in genetically susceptible individuals. Results from animal models of colitis and human studies indicate a role for innate lymphoid cells (ILC) in the pathogenesis of chronic intestinal inflammation in IBD. ILC are a population of lymphocytes that are enriched at mucosal sites, where they play a protective role against pathogens including extracellular bacteria, helminthes, and viruses. ILC lack an antigen-specific receptor, but can respond to environmental stress signals contributing to the rapid orchestration of an early immune response. Several subsets of ILC reflecting functional characteristics of T helper subsets have been described. ILC1 express the transcription factor T-bet and are characterized by secretion of IFNγ, ILC2 are GATA3+ and secrete IL5 and IL13 and ILC3 depend on expression of RORγt and secrete IL17 and IL22. However, ILC retain a degree of plasticity depending on exposure to cytokines and environmental factors. IL23 responsive ILC have been implicated in the pathogenesis of colitis in several innate murine models through the production of IL17, IFNγ, and GM-CSF. We have previously identified IL23 responsive ILC in the human intestine and found that they accumulate in the inflamed colon and small bowel of patients with CD. Other studies have confirmed accumulation of ILC in CD with increased frequencies of IFNγ-secreting ILC1 in both the intestinal lamina propria and the epithelium. Moreover, IL23 driven IL22 producing ILC have been shown to drive bacteria-induced colitis-associated cancer in mice. Interestingly, our data show increased ILC accumulation in patients with IBD and primary sclerosing cholangitis, who carry an increased risk of

Innate Lymphoid Cells in Intestinal Inflammation

Directory of Open Access Journals (Sweden)

Alessandra Geremia

2017-10-01

Full Text Available Inflammatory bowel disease (IBD is a chronic inflammatory disorder of the intestine that encompasses Crohn’s disease (CD and ulcerative colitis. The cause of IBD is unknown, but the evidence suggests that an aberrant immune response toward the commensal bacterial flora is responsible for disease in genetically susceptible individuals. Results from animal models of colitis and human studies indicate a role for innate lymphoid cells (ILC in the pathogenesis of chronic intestinal inflammation in IBD. ILC are a population of lymphocytes that are enriched at mucosal sites, where they play a protective role against pathogens including extracellular bacteria, helminthes, and viruses. ILC lack an antigen-specific receptor, but can respond to environmental stress signals contributing to the rapid orchestration of an early immune response. Several subsets of ILC reflecting functional characteristics of T helper subsets have been described. ILC1 express the transcription factor T-bet and are characterized by secretion of IFNγ, ILC2 are GATA3+ and secrete IL5 and IL13 and ILC3 depend on expression of RORγt and secrete IL17 and IL22. However, ILC retain a degree of plasticity depending on exposure to cytokines and environmental factors. IL23 responsive ILC have been implicated in the pathogenesis of colitis in several innate murine models through the production of IL17, IFNγ, and GM-CSF. We have previously identified IL23 responsive ILC in the human intestine and found that they accumulate in the inflamed colon and small bowel of patients with CD. Other studies have confirmed accumulation of ILC in CD with increased frequencies of IFNγ-secreting ILC1 in both the intestinal lamina propria and the epithelium. Moreover, IL23 driven IL22 producing ILC have been shown to drive bacteria-induced colitis-associated cancer in mice. Interestingly, our data show increased ILC accumulation in patients with IBD and primary sclerosing cholangitis, who carry an

Salmonella Typhimurium infection in the porcine intestine

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Schauser, Kirsten; Olsen, John Elmerdahl; Larsson, Lars-Inge

2005-01-01

The normal intestinal epithelium is renewed with a turnover rate of 3-5 days. During Salmonella infection increased cell loss is observed, possibly as a result of programmed cell death (PCD). We have, therefore, studied the effects of Salmonella Typhimurium infection on three elements involved...... in scattered epithelial cells and the number of positive cells increased with increasing times of exposure to Salmonella (P

The junctional epithelium originates from the odontogenic epithelium of an erupted tooth.

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Yajima-Himuro, Sara; Oshima, Masamitsu; Yamamoto, Gou; Ogawa, Miho; Furuya, Madoka; Tanaka, Junichi; Nishii, Kousuke; Mishima, Kenji; Tachikawa, Tetsuhiko; Tsuji, Takashi; Yamamoto, Matsuo

2014-05-02

The junctional epithelium (JE) is an epithelial component that is directly attached to the tooth surface and has a protective function against periodontal diseases. In this study, we determined the origin of the JE using a bioengineered tooth technique. We transplanted the bioengineered tooth germ into the alveolar bone with an epithelial component that expressed green fluorescence protein. The reduced enamel epithelium from the bioengineered tooth fused with the oral epithelium, and the JE was apparently formed around the bioengineered tooth 50 days after transplantation. Importantly, the JE exhibited green fluorescence for at least 140 days after transplantation, suggesting that the JE was not replaced by oral epithelium. Therefore, our results demonstrated that the origin of the JE was the odontogenic epithelium, and odontogenic epithelium-derived JE was maintained for a relatively long period.

Glucose, epithelium, and enteric nervous system: dialogue in the dark.

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Pfannkuche, H; Gäbel, G

2009-06-01

The gastrointestinal epithelium is in close contact with the various components of the chymus, including nutrients, bacteria and toxins. The epithelial barrier has to decide which components are effectively absorbed and which components are extruded. In the small intestine, a nutrient like glucose is mainly absorbed by the sodium linked glucose cotransporter 1 (SGLT1) and the glucose transporter 2 (GLUT2). The expression and activity of both transport proteins is directly linked to the amount of intraluminal glucose. Besides the direct interaction between glucose and the enterocytes, glucose also stimulates different sensory mechanisms within the intestinal wall. The most important types of cells involved in the sensing of intraluminal contents are enteroendocrine cells and neurones of the enteric nervous system. Regarding glucosensing, a distinct type of enteroendocrine cells, the enterochromaffine (EC) cells are involved. Excitation of EC cells by intraluminal glucose results in the release of serotonin (5-HT), which modulates epithelial functions and activates enteric secretomotorneurones. Enteric neurones are not only activated by 5-HT, but also directly by glucose. The activation of different cell types and the subsequent crosstalk between these cells may trigger appropriate absorptive and secretory processes within the intestine.

ER Stress Causes Rapid Loss of Intestinal Epithelial Stemness through Activation of the Unfolded Protein Response

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Jarom Heijmans

2013-04-01

Full Text Available Stem cells generate rapidly dividing transit-amplifying cells that have lost the capacity for self-renewal but cycle for a number of times until they exit the cell cycle and undergo terminal differentiation. We know very little of the type of signals that trigger the earliest steps of stem cell differentiation and mediate a stem cell to transit-amplifying cell transition. We show that in normal intestinal epithelium, endoplasmic reticulum (ER stress and activity of the unfolded protein response (UPR are induced at the transition from stem cell to transit-amplifying cell. Induction of ER stress causes loss of stemness in a Perk-eIF2α-dependent manner. Inhibition of Perk-eIF2α signaling results in stem cell accumulation in organoid culture of primary intestinal epithelium. Our findings show that the UPR plays an important role in the regulation of intestinal epithelial stem cell differentiation.

Autophagy and tight junction proteins in the intestine and intestinal diseases

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Chien-An A. Hu

2015-09-01

Full Text Available The intestinal epithelium (IE forms an indispensible barrier and interface between the intestinal interstitium and the luminal environment. The IE regulates water, ion and nutrient transport while providing a barrier against toxins, pathogens (bacteria, fungi and virus and antigens. The apical intercellular tight junctions (TJ are responsible for the paracellular barrier function and regulate trans-epithelial flux of ions and solutes between adjacent cells. Increased intestinal permeability caused by defects in the IE TJ barrier is considered an important pathogenic factor for the development of intestinal inflammation, diarrhea and malnutrition in humans and animals. In fact, defects in the IE TJ barrier allow increased antigenic penetration, resulting in an amplified inflammatory response in inflammatory bowel disease (IBD, necrotizing enterocolitis and ischemia-reperfusion injury. Conversely, the beneficial enhancement of the intestinal TJ barrier has been shown to resolve intestinal inflammation and apoptosis in both animal models of IBD and human IBD. Autophagy (self-eating mechanism is an intracellular lysosome-dependent degradation and recycling pathway essential for cell survival and homeostasis. Dysregulated autophagy has been shown to be directly associated with many pathological processes, including IBD. Importantly, the crosstalk between IE TJ and autophagy has been revealed recently. We showed that autophagy enhanced IE TJ barrier function by increasing transepithelial resistance and reducing the paracellular permeability of small solutes and ions, which is, in part, by targeting claudin-2, a cation-selective, pore-forming, transmembrane TJ protein, for lysosome (autophagy-mediated degradation. Interestingly, previous studies have shown that the inflamed intestinal mucosa in patients with active IBD has increased claudin-2 expression. In addition, inflammatory cytokines (for example, tumor necrosis factor-α, interleukin-6

Activation of Sox3 Gene by Thyroid Hormone in the Developing Adult Intestinal Stem Cell During Xenopus Metamorphosis

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Sun, Guihong; Fu, Liezhen; Wen, Luan

2014-01-01

The maturation of the intestine into the adult form involves the formation of adult stem cells in a thyroid hormone (T3)-dependent process in vertebrates. In mammals, this takes place during postembryonic development, a period around birth when the T3 level peaks. Due to the difficulty of manipulating late-stage, uterus-enclosed embryos, very little is known about the development of the adult intestinal stem cells. Interestingly, the remodeling of the intestine during the T3-dependent amphibian metamorphosis mimics the maturation of mammalian intestine. Our earlier microarray studies in Xenopus laevis revealed that the transcription factor SRY (sex-determining region Y)-box 3 (Sox3), well known for its involvement in neural development, was upregulated in the intestinal epithelium during metamorphosis. Here, we show that Sox3 is highly and specifically expressed in the developing adult intestinal progenitor/stem cells. We further show that its induction by T3 is independent of new protein synthesis, suggesting that Sox3 is directly activated by liganded T3 receptor. Thus, T3 activates Sox3 as one of the earliest changes in the epithelium, and Sox3 in turn may facilitate the dedifferentiation of the larval epithelial cells into adult stem cells. PMID:25211587

Gut microbial colonization orchestrates TLR2 expression, signaling and epithelial proliferation in the small intestinal mucosa.

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Nives Hörmann

Full Text Available The gut microbiota is an environmental factor that determines renewal of the intestinal epithelium and remodeling of the intestinal mucosa. At present, it is not resolved if components of the gut microbiota can augment innate immune sensing in the intestinal epithelium via the up-regulation of Toll-like receptors (TLRs. Here, we report that colonization of germ-free (GF Swiss Webster mice with a complex gut microbiota augments expression of TLR2. The microbiota-dependent up-regulation of components of the TLR2 signaling complex could be reversed by a 7 day broad-spectrum antibiotic treatment. TLR2 downstream signaling via the mitogen-activated protein kinase (ERK1/2 and protein-kinase B (AKT induced by bacterial TLR2 agonists resulted in increased proliferation of the small intestinal epithelial cell line MODE-K. Mice that were colonized from birth with a normal gut microbiota (conventionally-raised; CONV-R showed signs of increased small intestinal renewal and apoptosis compared with GF controls as indicated by elevated mRNA levels of the proliferation markers Ki67 and Cyclin D1, elevated transcripts of the apoptosis marker Caspase-3 and increased numbers of TUNEL-positive cells per intestinal villus structure. In accordance, TLR2-deficient mice showed reduced proliferation and reduced apoptosis. Our findings suggest that a tuned proliferation response of epithelial cells following microbial colonization could aid to protect the host from its microbial colonizers and increase intestinal surface area.

Disruption of estrogen receptor signaling enhances intestinal neoplasia in ApcMin/+ mice

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Cleveland, Alicia G.; Oikarinen, Seija I.; Bynoté, Kimberly K.; Marttinen, Maija; Rafter, Joseph J.; Gustafsson, Jan-Åke; Roy, Shyamal K.; Pitot, Henry C.; Korach, Kenneth S.; Lubahn, Dennis B.; Mutanen, Marja; Gould, Karen A.

2009-01-01

Estrogen receptors (ERs) [ERα (Esr1) and ERβ (Esr2)] are expressed in the human colon, but during the multistep process of colorectal carcinogenesis, expression of both ERα and ERβ is lost, suggesting that loss of ER function might promote colorectal carcinogenesis. Through crosses between an ERα knockout and ApcMin mouse strains, we demonstrate that ERα deficiency is associated with a significant increase in intestinal tumor multiplicity, size and burden in ApcMin/+ mice. Within the normal intestinal epithelium of ApcMin/+ mice, ERα deficiency is associated with an accumulation of nuclear β-catenin, an indicator of activation of the Wnt–β-catenin-signaling pathway, which is known to play a critical role in intestinal cancers. Consistent with the hypothesis that ERα deficiency is associated with activation of Wnt–β-catenin signaling, ERα deficiency in the intestinal epithelium of ApcMin/+ mice also correlated with increased expression of Wnt–β-catenin target genes. Through crosses between an ERβ knockout and ApcMin mouse strains, we observed some evidence that ERβ deficiency is associated with an increased incidence of colon tumors in ApcMin/+ mice. This effect of ERβ deficiency does not involve modulation of Wnt–β-catenin signaling. Our studies suggest that ERα and ERβ signaling modulate colorectal carcinogenesis, and ERα does so, at least in part, by regulating the activity of the Wnt–β-catenin pathway. PMID:19520794

Proteomic analysis of the intestinal adaptation response reveals altered expression of fatty acid binding proteins following massive small bowel resection.

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Stephens, Andrew N; Pereira-Fantini, Prue M; Wilson, Guineva; Taylor, Russell G; Rainczuk, Adam; Meehan, Katie L; Sourial, Magdy; Fuller, Peter J; Stanton, Peter G; Robertson, David M; Bines, Julie E

2010-03-05

Intestinal adaptation in response to the loss of the small intestine is essential to restore enteral autonomy in patients who have undergone massive small bowel resection (MSBR). In a proportion of patients, intestinal function is not restored, resulting in chronic intestinal failure (IF). Early referral of such patients for transplant provides the best prognosis; however, the molecular mechanisms underlying intestinal adaptation remain elusive and there is currently no convenient marker to predict whether patients will develop IF. We have investigated the adaptation response in a well-characterized porcine model of intestinal adaptation. 2D DIGE analysis of ileal epithelium from piglets recovering from massive small bowel resection (MSBR) identified over 60 proteins that changed specifically in MSBR animals relative to nonoperational or sham-operated controls. Three fatty acid binding proteins (L-FABP, FABP-6, and I-FABP) showed changes in MSBR animals. The expression changes and localization of each FABP were validated by immunoblotting and immunohistochemical analysis. FABP expression changes in MSBR animals occurred concurrently with altered triglyceride and bile acid metabolism as well as weight gain. The observed FABP expression changes in the ileal epithelium occur as part of the intestinal adaptation response and could provide a clinically useful marker to evaluate adaptation following MSBR.

Human-derived probiotic Lactobacillus reuteri strains differentially reduce intestinal inflammation.

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Liu, Yuying; Fatheree, Nicole Y; Mangalat, Nisha; Rhoads, Jon Marc

2010-11-01

Lactobacillus reuteri (L. reuteri) is a probiotic that inhibits the severity of enteric infections and modulates the immune system. Human-derived L. reuteri strains DSM17938, ATCC PTA4659, ATCC PTA 5289, and ATCC PTA 6475 have demonstrated strain-specific immunomodulation in cultured monocytoid cells, but information about how these strains affect inflammation in intestinal epithelium is limited. We determined the effects of the four different L. reuteri strains on lipopolysaccharide (LPS)-induced inflammation in small intestinal epithelial cells and in the ileum of newborn rats. IPEC-J2 cells (derived from the jejunal epithelium of a neonatal piglet) and IEC-6 cells (derived from the rat crypt) were treated with L. reuteri. Newborn rat pups were gavaged cow milk formula supplemented with L. reuteri strains in the presence or absence of LPS. Protein and mRNA levels of cytokines and histological changes were measured. We demonstrate that even though one L. reuteri strain (DSM 17938) did not inhibit LPS-induced IL-8 production in cultured intestinal cells, all strains significantly reduced intestinal mucosal levels of KC/GRO (∼IL-8) and IFN-γ when newborn rat pups were fed formula containing LPS ± L. reuteri. Intestinal histological damage produced by LPS plus cow milk formula was also significantly reduced by all four strains. Cow milk formula feeding (without LPS) produced mild gut inflammation, evidenced by elevated mucosal IFN-γ and IL-13 levels, a process that could be suppressed by strain 17938. Other cytokines and chemokines were variably affected by the different strains, and there was no toxic effect of L. reuteri on intestinal cells or mucosa. In conclusion, L. reuteri strains differentially modulate LPS-induced inflammation. Probiotic interactions with both epithelial and nonepithelial cells in vivo must be instrumental in modulating intrinsic anti-inflammatory effects in the intestine. We suggest that the terms anti- and proinflammatory be used only

Glycoprotein A33 deficiency: a new mouse model of impaired intestinal epithelial barrier function and inflammatory disease

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Benjamin B. Williams

2015-08-01

Full Text Available The cells of the intestinal epithelium provide a selectively permeable barrier between the external environment and internal tissues. The integrity of this barrier is maintained by tight junctions, specialised cell-cell contacts that permit the absorption of water and nutrients while excluding microbes, toxins and dietary antigens. Impairment of intestinal barrier function contributes to multiple gastrointestinal disorders, including food hypersensitivity, inflammatory bowel disease (IBD and colitis-associated cancer (CAC. Glycoprotein A33 (GPA33 is an intestinal epithelium-specific cell surface marker and member of the CTX group of transmembrane proteins. Roles in cell-cell adhesion have been demonstrated for multiple CTX family members, suggesting a similar function for GPA33 within the gastrointestinal tract. To test a potential requirement for GPA33 in intestinal barrier function, we generated Gpa33−/− mice and subjected them to experimental regimens designed to produce food hypersensitivity, colitis and CAC. Gpa33−/− mice exhibited impaired intestinal barrier function. This was shown by elevated steady-state immunosurveillance in the colonic mucosa and leakiness to oral TRITC-labelled dextran after short-term exposure to dextran sodium sulphate (DSS to injure the intestinal epithelium. Gpa33−/− mice also exhibited rapid onset and reduced resolution of DSS-induced colitis, and a striking increase in the number of colitis-associated tumours produced by treatment with the colon-specific mutagen azoxymethane (AOM followed by two cycles of DSS. In contrast, Gpa33−/− mice treated with AOM alone showed no increase in sporadic tumour formation, indicating that their increased tumour susceptibility is dependent on inflammatory stimuli. Finally, Gpa33−/− mice displayed hypersensitivity to food allergens, a common co-morbidity in humans with IBD. We propose that Gpa33−/− mice provide a valuable model to study the mechanisms

Studies on colon cancer prone rats. Spontaneous small intestinal carcinomas and tumor induction of small intestine by x-irradiation

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Maeura, Y [Osaka Univ. (Japan). Faculty of Medicine

1979-12-01

Histological investigation was carried out for Wister-Furth (WF) rats, prone to cancers of the colon and small intestine. Gastric cancer was observed in about 1/4 of the rats with the cancers of the colon and the small intestine, indicating that these rats could be the model animals of the cancer family syndrome with multi-cancers in the gastrointestinal tracts. The small intestine of WF and SD (Sprague-Dowley) rats as exposed to 1000, 2 x 1000, 1500, and 2000 R of x-rays at a dose rate of 157 R/min. In each group the stomach, small intestine, cecum, and colon were histologically investigated, immediately and 15, 25, and 35 weeks after irradiation. The rates of cancer occurrence in 15, 25, and 35 weeks were 5/17, 9/19, and 9/14 for WF strain and 1/8, 2/7, and 2/8 for SD strain, respectively. The rate increased with the increment of the days after irradiation. It was suggested that the atypical epithelium of the gastrointestinal tracts induced the cancer in high rates when some trigger was added.

Loss of miR-10a activates Lpo and collaborates with activated Wnt signaling in inducing intestinal Neoplasia in female mice

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Stadthagen Gomez, Gustavo; Tehler, Disa Elisabet; Høyland-Kroghsbo, Nina Molin

2013-01-01

, in the Apc(min) mouse model of intestinal neoplasia, female miR-10a deficient mice develop significantly more adenomas than miR-10(+/+) and male controls. We further found that Lpo is extensively upregulated in the intestinal epithelium of mice deprived of miR-10a. Using in vitro assays, we demonstrate...... that the primary miR-10a target KLF4 can upregulate transcription of Lpo, whereas siRNA knockdown of KLF4 reduces LPO levels in HCT-116 cells. Furthermore, Klf4 is upregulated in the intestines of miR-10a knockout mice. Lpo has previously been shown to have the capacity to oxidize estrogens into potent...... depurinating mutagens, creating an instable genomic environment that can cause initiation of cancer. Therefore, we postulate that Lpo upregulation in the intestinal epithelium of miR-10a deficient mice together with the predominant abundance of estrogens in female animals mainly accounts for the sex...

Substrate metabolism in isolated rat jejunal epithelium. Analysis using 14C-radioisotopes

International Nuclear Information System (INIS)

Mallet, R.T.

1986-01-01

The jejunal epithelium absorbs nutrients from the intestinal lumen and is therefore the initial site for metabolism of these compounds. The purpose of this investigation is to analyze substrate metabolism in a preparation of jejunal epithelium relatively free of other tissues. Novel radioisotopic labelling techniques allow quantitation of substrate metabolism in the TCA cycle, Embden-Meyerhof (glycolytic) pathway, and hexose monophosphate shunt. For example, ratios of 14 CO 2 production from pairs of 14 C-pyruvate, and 14 C-succinate radioisotopes (CO 2 ratios) indicate the probability of TCA cycle intermediate efflux to generate compounds other than CO 2 . With (2,3- 14 C)succinate as tracer, the ratio of 14 C in carbon 4 + 5 versus carbon 2 + 3 of citrate, the citrate labelling ratio, equals the probability of TCA intermediate flux to the acetyl CoA-derived portion of citrate versus flux to the oxaloacetate-derived portion. The principal metabolic substrates for the jejunal epithelium are glucose and glutamine. CO 2 ratios indicate that glutamine uptake and metabolism is partially Na + -independent, and is saturable, with a half-maximal rate at physiological plasma glutamine concentrations. Glucose metabolism in the jejunal epithelium proceeds almost entirely via the Embden-Meyerhof pathway. Conversion of substrates to multi-carbon products in this tissue allows partial conservation of reduced carbon for further utilization in other tissues. In summary, metabolic modeling based on 14 C labelling ratios is a potentially valuable technique for analysis of metabolic flux patterns in cell preparations

Cytological and Morphological Analyses Reveal Distinct Features of Intestinal Development during Xenopus tropicalis Metamorphosis

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Matsuura, Kazuo; Shi, Yun-Bo

2012-01-01

Background The formation and/or maturation of adult organs in vertebrates often takes place during postembryonic development, a period around birth in mammals when thyroid hormone (T3) levels are high. The T3-dependent anuran metamorphosis serves as a model to study postembryonic development. Studies on the remodeling of the intestine during Xenopus (X.) laevis metamorphosis have shown that the development of the adult intestine involves de novo formation of adult stem cells in a process controlled by T3. On the other hand, X. tropicalis, highly related to X. laevis, offers a number of advantages for studying developmental mechanisms, especially at genome-wide level, over X. laevis, largely due to its shorter life cycle and sequenced genome. To establish X. tropicalis intestinal metamorphosis as a model for adult organogenesis, we analyzed the morphological and cytological changes in X. tropicalis intestine during metamorphosis. Methodology/Principal Findings We observed that in X. tropicalis, the premetamorphic intestine was made of mainly a monolayer of larval epithelial cells surrounded by little connective tissue except in the single epithelial fold, the typhlosole. During metamorphosis, the larval epithelium degenerates and adult epithelium develops to form a multi-folded structure with elaborate connective tissue and muscles. Interestingly, typhlosole, which is likely critical for adult epithelial development, is present along the entire length of the small intestine in premetamorphic tadpoles, in contrast to X. laevis, where it is present only in the anterior 1/3. T3-treatment induces intestinal remodeling, including the shortening of the intestine and the typhlosole, just like in X. laevis. Conclusions/Significance Our observations indicate that the intestine undergoes similar metamorphic changes in X. laevis and X. tropicalis, making it possible to use the large amount of information available on X. laevis intestinal metamorphosis and the genome sequence

Cranberry extract inhibits in vitro adhesion of F4 and F18+Escherichia coli to pig intestinal epithelium and reduces in vivo excretion of pigs orally challenged with F18+ verotoxigenic E. coli.

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Coddens, Annelies; Loos, Michaela; Vanrompay, Daisy; Remon, Jean Paul; Cox, Eric

2017-04-01

F4 + E. coli and F18 + E. coli infections are an important threat for pig industry worldwide. Antibiotics are commonly used to treat infected piglets, but the emerging development of resistance against antibiotics raises major concerns. Hence, alternative therapies to prevent pigs from F4 + E. coli and F18 + E. coli infections need to be developed. Since cranberry previously showed anti-adhesive activity against uropathogenic E. coli, we aimed to investigate whether cranberry extract could also inhibit binding of F4 + E. coli and F18 + E. coli to pig intestinal epithelium. Using the in vitro villus adhesion assay, we found that low concentrations of cranberry extract (20μg or 100μg/ml) have strong inhibitory activity on F4 + E. coli (75.3%, S.D.=9.31 or 95.8%, S.D.=2.56, respectively) and F18 + E. coli adherence (100% inhibition). This effect was not due to antimicrobial activity. Moreover, cranberry extract (10mg or 100mg) could also abolish in vivo binding of F4 and F18 fimbriae to the pig intestinal epithelium in ligated loop experiments. Finally, two challenge experiments with F18 + E. coli were performed to address the efficacy of in-feed or water supplemented cranberry extract. No effect could be observed in piglets that received cranberry extract only in feed (1g/kg or 10g/kg). However, supplementation of feed (10g/kg) and drinking water (1g/L) significantly decreased excretion and diarrhea. The decreased infection resulted in a decreased serum antibody response indicating reduced exposure to F18 + E. coli. Copyright © 2017 Elsevier B.V. All rights reserved.

Conjugated effects of thyroxine and X-rays on the intestinal wall of Alytes obstetricans Larvae (Anuran Amphibian)

International Nuclear Information System (INIS)

Dauca, M.; Hourdry, J.

1979-01-01

The conjoined effects of thyroxine and X-rays on the intestinal wall were studied using Alytes obstetricans tadpoles in premetamorphosis. Thyroxine alone induced degeneration of the larval epithelium (primary epithelium) and its replacement by a secondary epithelium. The latter is derived from stem cells via the development of islets. In animals submitted to irradiation only, many of these stem cells showed signs of necrosis. In irradiated larvae treated with thyroxine, the secondary epitheliocytes were rare and never formed islets. Radioautographic observations confirmed their very low proliferation rate. Contrary to what was observed in the hormone treated larvae, cell fragments of the primary epithelium were extruded in the connective tissue, and phagocytes appear to infiltrate the epithelium. In animals treated with thyroxine and later submitted to irradiation, islets of secondary epitheliocytes developed while some cells degenerated. There again, the phagocytes were noted in both the connective tissue and the epithelium. (orig.) [de

Human zonulin, a potential modulator of intestinal tight junctions.

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Wang, W; Uzzau, S; Goldblum, S E; Fasano, A

2000-12-01

Intercellular tight junctions are dynamic structures involved in vectorial transport of water and electrolytes across the intestinal epithelium. Zonula occludens toxin derived from Vibrio cholerae interacts with a specific intestinal epithelial surface receptor, with subsequent activation of a complex intracellular cascade of events that regulate tight junction permeability. We postulated that this toxin may mimic the effect of a functionally and immunologically related endogenous modulator of intestinal tight junctions. Affinity-purified anti-zonula occludens toxin antibodies and the Ussing chamber assay were used to screen for one or more mammalian zonula occludens toxin analogues in both fetal and adult human intestine. A novel protein, zonulin, was identified that induces tight junction disassembly in non-human primate intestinal epithelia mounted in Ussing chambers. Comparison of amino acids in the active zonula occludens toxin fragment and zonulin permitted the identification of the putative receptor binding domain within the N-terminal region of the two proteins. Zonulin likely plays a pivotal role in tight junction regulation during developmental, physiological, and pathological processes, including tissue morphogenesis, movement of fluid, macromolecules and leukocytes between the intestinal lumen and the interstitium, and inflammatory/autoimmune disorders.

Integrin Beta 1 Suppresses Multilayering of a Simple Epithelium

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Chen, Jichao; Krasnow, Mark A.

2012-01-01

Epithelia are classified as either simple, a single cell layer thick, or stratified (multilayered). Stratified epithelia arise from simple epithelia during development, and transcription factor p63 functions as a key positive regulator of epidermal stratification. Here we show that deletion of integrin beta 1 (Itgb1) in the developing mouse airway epithelium abrogates airway branching and converts this monolayer epithelium into a multilayer epithelium with more than 10 extra layers. Mutant lung epithelial cells change mitotic spindle orientation to seed outer layers, and cells in different layers become molecularly and functionally distinct, hallmarks of normal stratification. However, mutant lung epithelial cells do not activate p63 and do not switch to the stratified keratin profile of epidermal cells. These data, together with previous data implicating Itgb1 in regulation of epidermal stratification, suggest that the simple-versus-stratified developmental decision may involve not only stratification inducers like p63 but suppressors like Itgb1 that prevent simple epithelia from inappropriately activating key steps in the stratification program. PMID:23285215

Regional specialization within the intestinal immune system

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Mowat, Allan M.; Agace, William Winston

2014-01-01

The intestine represents the largest compartment of the immune system. It is continually exposed to antigens and immunomodulatory agents from the diet and the commensal microbiota, and it is the port of entry for many clinically important pathogens. Intestinal immune processes are also increasingly...... implicated in controlling disease development elsewhere in the body. In this Review, we detail the anatomical and physiological distinctions that are observed in the small and large intestines, and we suggest how these may account for the diversity in the immune apparatus that is seen throughout...... the intestine. We describe how the distribution of innate, adaptive and innate-like immune cells varies in different segments of the intestine and discuss the environmental factors that may influence this. Finally, we consider the implications of regional immune specialization for inflammatory disease...

The role of innate signaling in the homeostasis of tolerance and immunity in the intestine.

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Wells, Jerry M; Loonen, Linda M P; Karczewski, Jurgen M

2010-01-01

In the intestine innate recognition of microbes is achieved through pattern recognition receptor (PRR) families expressed in immune cells and different cell lineages of the intestinal epithelium. Toll-like receptor (TLR) and nucleotide-binding and oligomerization domain-like receptor (NLR) families are emerging as key mediators of immunity through their role as maturation factors of immune cells and triggers for the production of cytokines and chemokines and antimicrobial factors. At the mucosal surface chronic activation of the immune system is avoided through the epithelial production of a glycocalyx, steady-state production of antimicrobial factors as well as the selective expression and localization of PRRs. Additionally, the polarization of epithelial TLR signaling and suppression of NF-kappaB activation by luminal commensals appears to contribute to the homeostasis of tolerance and immunity. Several studies have demonstrated that TLR signaling in epithelial cells contributes to a range of homeostatic mechanisms including proliferation, wound healing, epithelial integrity, and regulation of mucosal immune functions. The intestinal epithelium appears to have uniquely evolved to maintain mucosal tolerance and immunity, and future efforts to further understand the molecular mechanisms of intestinal homeostasis may have a major impact on human health. Copyright 2009 Elsevier GmbH. All rights reserved.

Molecular Characterization of Barrier Properties in Follicle-Associated Epithelium of Porcine Peyer's Patches Reveals Major Sealing Function of Claudin-4

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Judith Radloff

2017-08-01

Full Text Available The pig represents a preferred model for the analysis of intestinal immunology. However, the barrier of the follicle-associated epithelium (FAE covering porcine Peyer's patches (PP has not yet been characterized in detail. This study aimed to perform this characterization in order to pave the way toward an understanding of the functional contribution of epithelial barrier properties in gut immunology. Porcine tissue specimens were taken from the distal small intestine in order to obtain electrophysiological data of PP FAE and neighboring villous epithelium (VE, employing the Ussing chamber technique. Transepithelial resistance (TER and paracellular fluorescein flux were measured, and tissues were morphometrically compared. In selfsame tissues, expression and localization of major tight junction (TJ proteins (claudin-1, -2, -3, -4, -5, and -8 were analyzed. PP FAE specimens showed a higher TER and a lower apparent permeability for sodium fluorescein than VE. Immunoblotting revealed an expression of all claudins within both epithelia, with markedly stronger expression of the sealing TJ protein claudin-4 in PP FAE compared with the neighboring VE. Immunohistochemistry confirmed the expression and localization of all claudins in both PP FAE and VE, with stronger claudin-4 abundance in PP FAE. The results are in accordance with the physiological function of the FAE, which strongly regulates and limits antigen uptake determining a mandatory transcellular route for antigen presentation, highlighting the importance of this structure for the first steps of the intestinal immune response. Thus, this study provides detailed insights into the specific barrier properties of the porcine FAE covering intestinal PP, at the interface of intestinal immunology and barriology.

Intestinal stem cells in the adult Drosophila midgut

International Nuclear Information System (INIS)

Jiang, Huaqi; Edgar, Bruce A.

2011-01-01

Drosophila has long been an excellent model organism for studying stem cell biology. Notably, studies of Drosophila's germline stem cells have been instrumental in developing the stem cell niche concept. The recent discovery of somatic stem cells in adult Drosophila, particularly the intestinal stem cells (ISCs) of the midgut, has established Drosophila as an exciting model to study stem cell-mediated adult tissue homeostasis and regeneration. Here, we review the major signaling pathways that regulate the self-renewal, proliferation and differentiation of Drosophila ISCs, discussing how this regulation maintains midgut homeostasis and mediates regeneration of the intestinal epithelium after injury. -- Highlights: ► The homeostasis and regeneration of adult fly midguts are mediated by ISCs. ► Damaged enterocytes induce the proliferation of intestinal stem cells (ISC). ► EGFR and Jak/Stat signalings mediate compensatory ISC proliferation. ► Notch signaling regulates ISC self-renewal and differentiation.

Intestinal Failure: New Definition and Clinical Implications.

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Kappus, Matthew; Diamond, Sarah; Hurt, Ryan T; Martindale, Robert

2016-09-01

Intestinal failure (IF) is a state in which the nutritional demands of the body are not met by the gastrointestinal absorptive surface. It is a long-recognized complication associated with short bowel syndrome, which results in malabsorption after significant resection of the intestine for many reasons or functional dysmotility. Etiologies have included Crohn's disease, vascular complications, and the effects of radiation enteritis, as well as the effects of intestinal obstruction, dysmotility, or congenital defects. While IF has been long-recognized, it has historically not been uniformly defined, which has made both recognition and management challenging. This review examines the previous definitions of IF as well as the newer definition and classification of IF and how it is essential to IF clinical guidelines.

Conditional inactivation of p53 in mouse ovarian surface epithelium does not alter MIS driven Smad2-dominant negative epithelium-lined inclusion cysts or teratomas.

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Suzanne M Quartuccio

Full Text Available Epithelial ovarian cancer is the most lethal gynecological malignancy among US women. The etiology of this disease, although poorly understood, may involve the ovarian surface epithelium or the epithelium of the fallopian tube fimbriae as the progenitor cell. Disruptions in the transforming growth factor beta (TGFβ pathway and p53 are frequently found in chemotherapy-resistant serous ovarian tumors. Transgenic mice expressing a dominant negative form of Smad2 (Smad2DN, a downstream transcription factor of the TGFβ signaling pathway, targeted to tissues of the reproductive tract were created on a FVB background. These mice developed epithelium-lined inclusion cysts, a potential precursor lesion to ovarian cancer, which morphologically resembled oviductal epithelium but exhibited protein expression more closely resembling the ovarian surface epithelium. An additional genetic "hit" of p53 deletion was predicted to result in ovarian tumors. Tissue specific deletion of p53 in the ovaries and oviducts alone was attempted through intrabursal or intraoviductal injection of Cre-recombinase expressing adenovirus (AdCreGFP into p53 (flox/flox mice. Ovarian bursal cysts were detected in some mice 6 months after intrabursal injection. No pathological abnormalities were detected in mice with intraoviductal injections, which may be related to decreased infectivity of the oviductal epithelium with adenovirus as compared to the ovarian surface epithelium. Bitransgenic mice, expressing both the Smad2DN transgene and p53 (flox/flox, were then exposed to AdCreGFP in the bursa and oviductal lumen. These mice did not develop any additional phenotypes. Exposure to AdCreGFP is not an effective methodology for conditional deletion of floxed genes in oviductal epithelium and tissue specific promoters should be employed in future mouse models of the disease. In addition, a novel phenotype was observed in mice with high expression of the Smad2DN transgene as validated

HOXB4 Gene Expression Is Regulated by CDX2 in Intestinal Epithelial Cells

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Jørgensen, Steffen; Coshun, Mehmet; Mikkelsen Homburg, Keld

2016-01-01

analysis and expression data from Caco2 cells also suggests a role for CDX2 in the regulation of HOXB4 gene expression in the intestinal epithelium. Thus, the aim of this study was to investigate whether HOXB4 gene expression is regulated by CDX2 in the intestinal epithelium. We demonstrated binding of CDX......The mammalian Caudal-related homeobox transcription factor 2 (CDX2) plays a key role in the homeobox regulatory network and is essential in regulating the expression of several homeobox (HOX) genes during embryonic development, particularly in the gut. Genome-wide CDX2 chromatin immunoprecipitation......2 to four different CDX2 binding sites in an enhancer region located upstream of the HOXB4 transcription start site. Mutations in the CDX2 binding sites reduced HOXB4 gene activity, and knock down of endogenous CDX2 expression by shRNA reduced HOXB4 gene expression. This is the first report...

Distinct intestinal adaptation for vitamin B12 and bile acid absorption revealed in a new mouse model of massive ileocecal resection.

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Matsumoto, Yuka; Mochizuki, Wakana; Akiyama, Shintaro; Matsumoto, Taichi; Nozaki, Kengo; Watanabe, Mamoru; Nakamura, Tetsuya

2017-09-15

Ileocecal resection (ICR), one of several types of intestinal resection that results in short bowel syndrome (SBS), causes severe clinical disease in humans. We here describe a mouse model of massive ICR in which 75% of the distal small intestine is removed. We demonstrate that mice underwent 75% ICR show severe clinical signs and high mortality, which may recapitulate severe forms of human SBS, despite an adaptive response throughout the remnant intestine. By using this model, we also investigated whether the epithelium of the remnant intestine shows enhanced expression of factors involved in region-specific functions of the ileum. Cubn mRNA and its protein product, which play an essential role in vitamin B12 absorption in the ileum, are not compensatory up-regulated in any part of the remnant intestine, demonstrating a clear contrast with post-operative up-regulation of genes involved in bile acid absorption. Our study suggests that functional adaptation by phenotypical changes in the intestinal epithelium is not a general feature for nutrient absorption systems that are confined to the ileum. We also propose that the mouse model developed in this study will become a unique system to facilitate studies on SBS with ICR in humans. © 2017. Published by The Company of Biologists Ltd.

Distinct intestinal adaptation for vitamin B12 and bile acid absorption revealed in a new mouse model of massive ileocecal resection

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Yuka Matsumoto

2017-09-01

Full Text Available Ileocecal resection (ICR, one of several types of intestinal resection that results in short bowel syndrome (SBS, causes severe clinical disease in humans. We here describe a mouse model of massive ICR in which 75% of the distal small intestine is removed. We demonstrate that mice underwent 75% ICR show severe clinical signs and high mortality, which may recapitulate severe forms of human SBS, despite an adaptive response throughout the remnant intestine. By using this model, we also investigated whether the epithelium of the remnant intestine shows enhanced expression of factors involved in region-specific functions of the ileum. Cubn mRNA and its protein product, which play an essential role in vitamin B12 absorption in the ileum, are not compensatory up-regulated in any part of the remnant intestine, demonstrating a clear contrast with post-operative up-regulation of genes involved in bile acid absorption. Our study suggests that functional adaptation by phenotypical changes in the intestinal epithelium is not a general feature for nutrient absorption systems that are confined to the ileum. We also propose that the mouse model developed in this study will become a unique system to facilitate studies on SBS with ICR in humans.

Glucose stimulates intestinal epithelial crypt proliferation by modulating cellular energy metabolism.

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Zhou, Weinan; Ramachandran, Deepti; Mansouri, Abdelhak; Dailey, Megan J

2018-04-01

The intestinal epithelium plays an essential role in nutrient absorption, hormone release, and barrier function. Maintenance of the epithelium is driven by continuous cell renewal by stem cells located in the intestinal crypts. The amount and type of diet influence this process and result in changes in the size and cellular make-up of the tissue. The mechanism underlying the nutrient-driven changes in proliferation is not known, but may involve a shift in intracellular metabolism that allows for more nutrients to be used to manufacture new cells. We hypothesized that nutrient availability drives changes in cellular energy metabolism of small intestinal epithelial crypts that could contribute to increases in crypt proliferation. We utilized primary small intestinal epithelial crypts from C57BL/6J mice to study (1) the effect of glucose on crypt proliferation and (2) the effect of glucose on crypt metabolism using an extracellular flux analyzer for real-time metabolic measurements. We found that glucose increased both crypt proliferation and glycolysis, and the glycolytic pathway inhibitor 2-deoxy-d-glucose (2-DG) attenuated glucose-induced crypt proliferation. Glucose did not enhance glucose oxidation, but did increase the maximum mitochondrial respiratory capacity, which may contribute to glucose-induced increases in proliferation. Glucose activated Akt/HIF-1α signaling pathway, which might be at least in part responsible for glucose-induced glycolysis and cell proliferation. These results suggest that high glucose availability induces an increase in crypt proliferation by inducing an increase in glycolysis with no change in glucose oxidation. © 2017 Wiley Periodicals, Inc.

Steroid hormones as regulators of the proliferative activity of normal and neoplastic intestinal epithelial cells (review).

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Tutton, P J; Barkla, D H

1988-01-01

Glucocorticoid and mineralocorticoid receptors are present in normal epithelial cells of both the small and large intestine and there have also been contentious reports of androgen, oestrogen and progesterone receptors in the epithelium of the normal large intestine. The majority of reports suggest that stimulation of the intestinal glucocorticoid receptors results in increased proliferation of epithelial cells in the small bowel, as does stimulation of androgen receptors and possibly mineralocorticoid receptors. The proliferative response of the normal intestine to oestrogens is difficult to evaluate and that to progestigens appears not to have been reported. Epidemiological studies reveal a higher incidence of bowel cancer in premenopausal women than in men of the same age and yet there is a lower incidence of these tumors in women of higher parity. These findings have been atributted to a variety of non-epithelial gender characteristic such as differences in bile metabolism, colonic bacterial and fecal transit times. In experimental animals, androgens have also been shown to influence carcinogenesis and this could well be attributed to changes in food intake etc. However, many studies have now revealed steroid hormone receptors on colorectal tumor cells and thus a direct effect of the steroid hormones on the epithelium during and after malignant transformation must now be considered.

NOD-Like Receptors in Intestinal Homeostasis and Epithelial Tissue Repair

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Parlato, Marianna; Yeretssian, Garabet

2014-01-01

The intestinal epithelium constitutes a dynamic physical barrier segregating the luminal content from the underlying mucosal tissue. Following injury, the epithelial integrity is restored by rapid migration of intestinal epithelial cells (IECs) across the denuded area in a process known as wound healing. Hence, through a sequence of events involving restitution, proliferation and differentiation of IECs the gap is resealed and homeostasis reestablished. Relapsing damage followed by healing of the inflamed mucosa is a hallmark of several intestinal disorders including inflammatory bowel diseases (IBD). While several regulatory peptides, growth factors and cytokines stimulate restitution of the epithelial layer after injury, recent evidence in the field underscores the contribution of innate immunity in controlling this process. In particular, nucleotide-binding and oligomerization domain-like receptors (NLRs) play critical roles in sensing the commensal microbiota, maintaining homeostasis, and regulating intestinal inflammation. Here, we review the process of intestinal epithelial tissue repair and we specifically focus on the impact of NLR-mediated signaling mechanisms involved in governing epithelial wound healing during disease. PMID:24886810

Intestine-specific overexpression of IL-10 improves survival in polymicrobial sepsis.

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Rajan, Saju; Vyas, Dinesh; Clark, Andrew T; Woolsey, Cheryl A; Clark, Jessica A; Hotchkiss, Richard S; Buchman, Timothy G; Coopersmith, Craig M

2008-04-01

Targeted IL-10 therapy improves survival in preclinical models of critical illness, and intestine-specific IL-10 decreases inflammation in models of chronic Inflammatory disease. We therefore sought to determine whether intestine-specific overexpression of IL-10 would improve survival in sepsis. Transgenic mice that overexpress IL-10 in their gut epithelium (Fabpi-IL-10 mice) and wild-type (WT) littermates (n = 127) were subjected to cecal ligation and puncture with a 27-gauge needle. The 7-day survival rate was 45% in transgenic animals and 30% in WT animals (P < or = 0.05). Systemic levels of IL-10 were undetectable in both groups of animals under basal conditions and were elevated to a similar degree in septic animals regardless of whether they expressed the transgene. Local parameter of injury, including gut epithelial apoptosis, intestinal permeability, peritoneal lavage cytokines, and stimulated cytokines from intraepithelial lymphocytes, were similar between transgenic and WT mice. However, in stimulated splenocytes, proinflammatory cytokines monocyte chemoattractant protein 1 (189 +/- 43 vs. 40 +/- 8 pg/mL) and IL-6 (116 +/- 28 vs. 34 +/- 9 pg/mL) were lower in Fabpi-IL-10 mice than WT littermates despite the intestine-specific nature of the transgene (P < 0.05). Cytokine levels were similar in blood and bronchoalveolar lavage fluid between the 2 groups, as were circulating LPS levels. Transgenic mice also had lower white blood cell counts associated with lower absolute neutrophil counts (0.5 +/- 0.1 vs. 1.0 +/- 0.2 10(3)/mm3; P < 0.05). These results indicate that gut-specific overexpression of IL-10 improves survival in a murine model of sepsis, and interactions between the intestinal epithelium and the systemic immune system may play a role in conferring this survival advantage.

Three-Dimensional Organotypic Co-Culture Model of Intestinal Epithelial Cells and Macrophages to Study "Salmonella Enterica" Colonization Patterns

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Ott, Mark; Yang, J; Barilla, J.; Crabbe, A.; Sarker, S. F.; Liu, Y.

2017-01-01

Three-dimensional/3-D organotypic models of human intestinal epithelium mimic the differentiated form and function of parental tissues often not exhibited by 2-D monolayers and respond to Salmonella in ways that reflect in vivo infections. To further enhance the physiological relevance of 3-D models to more closely approximate in vivo intestinal microenvironments during infection, we developed and validated a novel 3-D intestinal co-culture model containing multiple epithelial cell types and phagocytic macrophages, and applied to study enteric infection by different Salmonella pathovars.

Prophylactic Ozone Administration Reduces Intestinal Mucosa Injury Induced by Intestinal Ischemia-Reperfusion in the Rat

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Ozkan Onal

2015-01-01

Full Text Available Objectives. Intestinal ischemia-reperfusion injury is associated with mucosal damage and has a high rate of mortality. Various beneficial effects of ozone have been shown. The aim of the present study was to show the effects of ozone in ischemia reperfusion model in intestine. Material and Method. Twenty eight Wistar rats were randomized into four groups with seven rats in each group. Control group was administered serum physiologic (SF intraperitoneally (ip for five days. Ozone group was administered 1 mg/kg ozone ip for five days. Ischemia Reperfusion (IR group underwent superior mesenteric artery occlusion for one hour and then reperfusion for two hours. Ozone + IR group was administered 1 mg/kg ozone ip for five days and at sixth day IR model was applied. Rats were anesthetized with ketamine∖xyzlazine and their intracardiac blood was drawn completely and they were sacrificed. Intestinal tissue samples were examined under light microscope. Levels of superoxide dismutase (SOD, catalase (CAT, glutathioneperoxidase (GSH-Px, malondyaldehide (MDA, and protein carbonyl (PCO were analyzed in tissue samples. Total oxidant status (TOS, and total antioxidant capacity (TAC were analyzed in blood samples. Data were evaluated statistically by Kruskal Wallis test. Results. In the ozone administered group, degree of intestinal injury was not different from the control group. IR caused an increase in intestinal injury score. The intestinal epithelium maintained its integrity and decrease in intestinal injury score was detected in Ozone + IR group. SOD, GSH-Px, and CAT values were high in ozone group and low in IR. TOS parameter was highest in the IR group and the TAC parameter was highest in the ozone group and lowest in the IR group. Conclusion. In the present study, IR model caused an increase in intestinal injury.In the present study, ozone administration had an effect improving IR associated tissue injury. In the present study, ozone therapy

Binding and movement of silver in the intestinal epithelium of a marine teleost fish, the European flounder (Platichthys flesus)

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Hogstrand, C.; Wood, C. M.; Bury, N.R.

2002-01-01

The intestine has been indicated as a site of waterborne silver toxicity in marine fish and chronic effects at the intestine have been observed at concentrations far below acutely toxic level. Thus, models of silver toxicity to marine fish need to consider the intestine as a biotic ligand....... The present study characterises binding of silver to the intestine of the European flounder (Platichthys flesus). Everted intestinal sacks were prepared and submersed in a solution mimicking the intestinal fluid of the fish at the acclimation salinity (21‰). Silver was added as 110mAgNO3 or 110mAgNO3/AgNO3...... mixtures at concentrations ranging from 1.6 to 950 nM total silver. Appearance of 110mAg was analysed in mucosal scrapings, muscle layers, and in the plasma saline on the serosal side of the intestine. The latter represented uptake into blood and other extra-intestinal compartments. Mucosal scrapings...

Intestinal stem cells in the adult Drosophila midgut

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Jiang, Huaqi, E-mail: Huaqi.Jiang@UTSouthwestern.edu [Department of Developmental Biology, UT Southwestern Medical Center, 6000 Harry Hines Blvd., Dallas, TX, 75235 (United States); Edgar, Bruce A., E-mail: b.edgar@dkfz.de [ZMBH-DKFZ Alliance, Im Neuenheimer Feld 282, D-69120 Heidelberg (Germany); Division of Basic Sciences, Fred Hutchinson Cancer Research Center, 1100 Fairview Ave. N., Seattle, WA 98109 (United States)

2011-11-15

Drosophila has long been an excellent model organism for studying stem cell biology. Notably, studies of Drosophila's germline stem cells have been instrumental in developing the stem cell niche concept. The recent discovery of somatic stem cells in adult Drosophila, particularly the intestinal stem cells (ISCs) of the midgut, has established Drosophila as an exciting model to study stem cell-mediated adult tissue homeostasis and regeneration. Here, we review the major signaling pathways that regulate the self-renewal, proliferation and differentiation of Drosophila ISCs, discussing how this regulation maintains midgut homeostasis and mediates regeneration of the intestinal epithelium after injury. -- Highlights: Black-Right-Pointing-Pointer The homeostasis and regeneration of adult fly midguts are mediated by ISCs. Black-Right-Pointing-Pointer Damaged enterocytes induce the proliferation of intestinal stem cells (ISC). Black-Right-Pointing-Pointer EGFR and Jak/Stat signalings mediate compensatory ISC proliferation. Black-Right-Pointing-Pointer Notch signaling regulates ISC self-renewal and differentiation.

Radioprotection of intestinal crypt cells by cox-inhibitors

International Nuclear Information System (INIS)

Bisnar, Paul O.; Dones, Rosa Angela S.A.; Serna, Paulene-Ver A.; Deocaris, Chester C.; Guttierez, Kalangitan V.; Deocaris, Custer C.

2006-01-01

The regulation of tissue homeostasis in the gastrointestinal epithelium after epithelial injury focuses on the prostaglandins(PGs) as its major mediators. The two cyclooxygenase isoforms, cox-1 and cox-2, catalyze synthesis of PGs. Cox-1 is the predominant cyclooxygenase isoform found in the normal intestine. In contrast, cox-2 is present at low levels in normal intestine but is elevated at sites of inflammation, and in adenomas and carcinomas. To study the effects of various commercially-available cox-inhibitors (Ketorolac: cox-1 selective; Celecoxib: cox-2 selective; and Indocid: cox-1/2 non-selective), we determine mouse crypt epithelial cell fate after genotoxic injury with whole-body gamma-ray exposure at 15 Gy. Intestinal tissues of mice treated with cox-2 inhibitors that showed invariable apoptotic event, however, have increased occurrence of regenerating cells. Our results suggest a potential application of cox-2 selective inhibitors as radioprotective agent for normal cells after radiotherapy. (Author)

Effects of probiotic on the intestinal morphology with special reference to the growth of broilers

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Lutfullah, G.; Ahmad, I.

2011-01-01

The probiotic (Protexin) increases the growth rate in broilers. It must interfere with the intestinal cell morphology and absorption. The intestinal epithelium is one of the most rapidly renewed tissues in the body and is renewed by a process of continuous cell division. This study was carried out with an aim to establish a link between the use of probiotic doses, growth rate, and intestinal cell proliferation by measuring the length and weight of the intestine and intestinal crypt cell proliferation (CCP) of broiler chicks. The results revealed significant increase in intestinal CCP but no effect was observed on the intestinal weight and length. The increase in CCP has also no significant influence towards growth factor. The increased weight gain in this study is associated with more feed consumption which is observed with Protexin dose 1.0 g / 10 kg of feed. Furthermore, feed consumption reduced beyond this dose may lead to reduced weight gain. (author)

Importance of Absent Neoplastic Epithelium in Patients Treated With Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy.

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Enblad, Malin; Birgisson, Helgi; Wanders, Alkwin; Sköldberg, Filip; Ghanipour, Lana; Graf, Wilhelm

2016-04-01

The importance of absent neoplastic epithelium in specimens from cytoreductive surgery (CRS) is unknown. This study aimed to investigate the prevalence and prognostic value of histopathology without neoplastic epithelium in patients treated with CRS and hyperthermic intraperitoneal chemotherapy (HIPEC). Data were extracted from medical records and histopathology reports for patients treated with initial CRS and HIPEC at Uppsala University Hospital, Sweden, between 2004 and 2012. Patients with inoperable disease and patients undergoing palliative non-CRS surgery were excluded from the study. Patients lacking neoplastic epithelium in surgical specimens from CRS, with or without mucin, were classified as "neoplastic epithelium absent" (NEA), and patients with neoplastic epithelium were classified as "neoplastic epithelium present" (NEP). The study observed NEA in 78 of 353 patients (22 %). Mucin was found in 28 of the patients with NEA. For low-grade appendiceal mucinous neoplasms and adenomas, the 5-year overall survival rate was 100 % for NEA and 84 % for NEP, and the 5-year recurrence-free survival rate was 100 % for NEA and 59 % for NEP. For appendiceal/colorectal adenocarcinomas (including tumors of the small intestine), the 5-year overall survival rate was 61 % for NEA and 38 % for NEP, and the 5-year recurrence-free survival rate was 60 % for NEA and 14 % for NEP. Carcinoembryonic antigen level, peritoneal cancer index, and completeness of the cytoreduction score were lower in patients with NEA. A substantial proportion of patients undergoing CRS and HIPEC have NEA. These patients have a favorable prognosis and a decreased risk of recurrence. Differences in patient selection can affect the proportion of NEA and hence explain differences in survival rates between reported series.

Mechanisms involved in alleviation of intestinal inflammation by bifidobacterium breve soluble factors.

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Elise Heuvelin

Full Text Available OBJECTIVES: Soluble factors released by Bifidobacterium breve C50 (Bb alleviate the secretion of pro-inflammatory cytokines by immune cells, but their effect on intestinal epithelium remains elusive. To decipher the mechanisms accounting for the cross-talk between bacteria/soluble factors and intestinal epithelium, we measured the capacity of the bacteria, its conditioned medium (Bb-CM and other Gram(+ commensal bacteria to dampen inflammatory chemokine secretion. METHODS: TNFalpha-induced chemokine (CXCL8 secretion and alteration of NF-kappaB and AP-1 signalling pathways by Bb were studied by EMSA, confocal microscopy and western blotting. Anti-inflammatory capacity was also tested in vivo in a model of TNBS-induced colitis in mice. RESULTS: Bb and Bb-CM, but not other commensal bacteria, induced a time and dose-dependent inhibition of CXCL8 secretion by epithelial cells driven by both AP-1 and NF-kappaB transcription pathways and implying decreased phosphorylation of p38-MAPK and IkappaB-alpha molecules. In TNBS-induced colitis in mice, Bb-CM decreased the colitis score and inflammatory cytokine expression, an effect reproduced by dendritic cell conditioning with Bb-CM. CONCLUSIONS: Bb and secreted soluble factors contribute positively to intestinal homeostasis by attenuating chemokine production. The results indicate that Bb down regulate inflammation at the epithelial level by inhibiting phosphorylations involved in inflammatory processes and by protective conditioning of dendritic cells.

Intestinal Permeability: The Basics

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Ingvar Bjarnason

1995-01-01

Full Text Available The authors review some of the more fundamental principles underlying the noninvasive assessment of intestinal permeability in humans, the choice of test markers and their analyses, and the practical aspects of test dose composition and how these can be changed to allow the specific assessment of regional permeability changes and other intestinal functions. The implications of increased intestinal permeability in the pathogenesis of human disease is discussed in relation to findings in patients with Crohn’s disease. A common feature of increased intestinal permeability is the development of a low grade enteropathy, and while quantitatively similar changes may be found in Crohn’s disease these seem to predict relapse of disease. Moreover, factors associated with relapse of Crohn’s disease have in common an action to increase intestinal permeability. While increased intestinal permeability does not seem to be important in the etiology of Crohn’s disease it may be a central mechanism in the clinical relapse of disease.

Genomic dissection of conserved transcriptional regulation in intestinal epithelial cells.

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Colin R Lickwar

2017-08-01

Full Text Available The intestinal epithelium serves critical physiologic functions that are shared among all vertebrates. However, it is unknown how the transcriptional regulatory mechanisms underlying these functions have changed over the course of vertebrate evolution. We generated genome-wide mRNA and accessible chromatin data from adult intestinal epithelial cells (IECs in zebrafish, stickleback, mouse, and human species to determine if conserved IEC functions are achieved through common transcriptional regulation. We found evidence for substantial common regulation and conservation of gene expression regionally along the length of the intestine from fish to mammals and identified a core set of genes comprising a vertebrate IEC signature. We also identified transcriptional start sites and other putative regulatory regions that are differentially accessible in IECs in all 4 species. Although these sites rarely showed sequence conservation from fish to mammals, surprisingly, they drove highly conserved IEC expression in a zebrafish reporter assay. Common putative transcription factor binding sites (TFBS found at these sites in multiple species indicate that sequence conservation alone is insufficient to identify much of the functionally conserved IEC regulatory information. Among the rare, highly sequence-conserved, IEC-specific regulatory regions, we discovered an ancient enhancer upstream from her6/HES1 that is active in a distinct population of Notch-positive cells in the intestinal epithelium. Together, these results show how combining accessible chromatin and mRNA datasets with TFBS prediction and in vivo reporter assays can reveal tissue-specific regulatory information conserved across 420 million years of vertebrate evolution. We define an IEC transcriptional regulatory network that is shared between fish and mammals and establish an experimental platform for studying how evolutionarily distilled regulatory information commonly controls IEC development

Dll1- and Dll4-mediated Notch signaling is required for homeostasis of intestinal stem cells

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Pellegrinet, Luca; Rodilla, Veronica; Liu, Zhenyi; Chen, Shuang; Koch, Ute; Espinosa, Lluis; Kaestner, Klaus H.; Kopan, Raphael; Lewis, Julian; Radtke, Freddy

2011-01-01

Background & Aims Ablation of Notch signaling within the intestinal epithelium results in loss of proliferating crypt progenitors, due to their conversion into post-mitotic secretory cells. We aimed to confirm that Notch was active in stem cells (SC), investigate consequences of loss of Notch signaling within the intestinal SC compartment, and identify the physiological ligands of Notch in mouse intestine. Furthermore, we investigated whether the induction of goblet cell differentiation that results from loss of Notch requires the transcription factor Krüppel-like factor 4 (Klf4). Methods Trasgenic mice that carried a reporter of Notch1 activation were used for lineage tracing experiments. The in vivo functions of the Notch ligands Jagged1 (Jag1), Delta-like1 (Dll1), Delta-like4 (Dll4), and the transcription factor Klf4 were assessed in mice with inducible, gut-specific gene targeting (Vil-Cre-ERT2). Results Notch1 signaling was found to be activated in intestinal SC. Although deletion of Jag1 or Dll4 did not perturb the intestinal epithelium, inactivation of Dll1 resulted in a moderate increase in number of goblet cells without noticeable effects of progenitor proliferation. However, simultaneous inactivation of Dll1 and Dll4 resulted in the complete conversion of proliferating progenitors into post-mitotic goblet cells, concomitant with loss of SC (Olfm4+, Lgr5+ and Ascl2+). Klf4 inactivation did not interfere with goblet cell differentiation in adult wild-type or in Notch pathway-deficient gut. Conclusions Notch signaling in SC and progenitors is activated by Dll1 and Dll4 ligands and is required for maintenance of intestinal progenitor and SC. Klf4 is dispensable for goblet cell differentiation in intestines of adult Notch-deficient mice. PMID:21238454

Dll1- and dll4-mediated notch signaling are required for homeostasis of intestinal stem cells.

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Pellegrinet, Luca; Rodilla, Veronica; Liu, Zhenyi; Chen, Shuang; Koch, Ute; Espinosa, Lluis; Kaestner, Klaus H; Kopan, Raphael; Lewis, Julian; Radtke, Freddy

2011-04-01

Ablation of Notch signaling within the intestinal epithelium results in loss of proliferating crypt progenitors due to their conversion into postmitotic secretory cells. We aimed to confirm that Notch was active in stem cells (SCs), investigate consequences of loss of Notch signaling within the intestinal SC compartment, and identify the physiologic ligands of Notch in mouse intestine. Furthermore, we investigated whether the induction of goblet cell differentiation that results from loss of Notch requires the transcription factor Krüppel-like factor 4 (Klf4). Transgenic mice that carried a reporter of Notch1 activation were used for lineage tracing experiments. The in vivo functions of the Notch ligands Jagged1 (Jag1), Delta-like1 (Dll1), Delta-like4 (Dll4), and the transcription factor Klf4 were assessed in mice with inducible, gut-specific gene targeting (Vil-Cre-ER(T2)). Notch1 signaling was found to be activated in intestinal SCs. Although deletion of Jag1 or Dll4 did not perturb the intestinal epithelium, inactivation of Dll1 resulted in a moderate increase in number of goblet cells without noticeable effects of progenitor proliferation. However, simultaneous inactivation of Dll1 and Dll4 resulted in the complete conversion of proliferating progenitors into postmitotic goblet cells, concomitant with loss of SCs (Olfm4(+), Lgr5(+), and Ascl2(+)). Klf4 inactivation did not interfere with goblet cell differentiation in adult wild-type or in Notch pathway-deficient gut. Notch signaling in SCs and progenitors is activated by Dll1 and Dll4 ligands and is required for maintenance of intestinal progenitor and SCs. Klf4 is dispensable for goblet cell differentiation in intestines of adult Notch-deficient mice. Copyright © 2011 AGA Institute. Published by Elsevier Inc. All rights reserved.

Mucin dynamics in intestinal bacterial infection.

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Sara K Lindén

Full Text Available Bacterial gastroenteritis causes morbidity and mortality in humans worldwide. Murine Citrobacter rodentium infection is a model for gastroenteritis caused by the human pathogens enteropathogenic Escherichia coli and enterohaemorrhagic E. coli. Mucin glycoproteins are the main component of the first barrier that bacteria encounter in the intestinal tract.Using Immunohistochemistry, we investigated intestinal expression of mucins (Alcian blue/PAS, Muc1, Muc2, Muc4, Muc5AC, Muc13 and Muc3/17 in healthy and C. rodentium infected mice. The majority of the C. rodentium infected mice developed systemic infection and colitis in the mid and distal colon by day 12. C. rodentium bound to the major secreted mucin, Muc2, in vitro, and high numbers of bacteria were found in secreted MUC2 in infected animals in vivo, indicating that mucins may limit bacterial access to the epithelial surface. In the small intestine, caecum and proximal colon, the mucin expression was similar in infected and non-infected animals. In the distal colonic epithelium, all secreted and cell surface mucins decreased with the exception of the Muc1 cell surface mucin which increased after infection (p<0.05. Similarly, during human infection Salmonella St Paul, Campylobacter jejuni and Clostridium difficile induced MUC1 in the colon.Major changes in both the cell-surface and secreted mucins occur in response to intestinal infection.

Spatial Localization and Binding of the Probiotic Lactobacillus farciminis to the Rat Intestinal Mucosa: Influence of Chronic Stress.

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Stéphanie Da Silva

Full Text Available The present study aimed at detecting the exogenously applied probiotic Lactobacillus farciminis in rats, after exposure to IBS-like chronic stress, based on 4-day Water Avoidance Stress (WAS. The presence of L. farciminis in both ileal and colonic mucosal tissues was demonstrated by FISH and qPCR, with ileum as the preferential niche, as for the SFB population. A different spatial distribution of the probiotic was observed: in the ileum, bacteria were organized in micro-colonies more or less close to the epithelium whereas, in the colon, they were mainly visualized far away from the epithelium. When rats were submitted to WAS, the L. farciminis population substantially decreased in both intestinal regions, due to a stress-induced increase in colonic motility and defecation, rather than a modification of bacterial binding to the intestinal mucin Muc2.

The Ciona intestinalis immune-related galectin genes (CiLgals-a and CiLgals-b) are expressed by the gastric epithelium.

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Parrinello, Daniela; Sanfratello, Maria Antonietta; Vizzini, Aiti; Testasecca, Lelia; Parrinello, Nicolò; Cammarata, Matteo

2017-03-01

The transcription of two Ciona intestinalis galectin genes (CiLgals-a and CiLgals-b) is uparegulated by LPS in the pharynxis (hemocytes, vessel epithelium, endostilar zones) which is retained the main organ of the immunity. In this ascidian, for the first time we show, by immunohistochemistry and in situ hybridization methods, that these two immune-related genes are expressed in the gastric epithelium of naïve ascidians, whereas the galectins appear to be only contained in the intestine columnar epithelium. In addition, according to previous results on the pharynx, the genes are also expressed and galectins produced by hemocytes scattered in the connective tissue surrounding the gut. The genes expression and galectin localization in several tissues, including the previous findings on the transcription upregulation, the constitutive expression of these genes by endostylar zones and by the gastric epithelium suggest a potential multifunctional role of these galectins. In this respect, it is of interest to define where the CiLgals are normally found as related to the tissue functions. Such an approach should be a starting point for further investigations. Copyright © 2017 Elsevier Ltd. All rights reserved.

Analysis of interactions of Salmonella type three secretion mutants with 3-D intestinal epithelial cells.

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Andrea L Radtke

Full Text Available The prevailing paradigm of Salmonella enteropathogenesis based on monolayers asserts that Salmonella pathogenicity island-1 Type Three Secretion System (SPI-1 T3SS is required for bacterial invasion into intestinal epithelium. However, little is known about the role of SPI-1 in mediating gastrointestinal disease in humans. Recently, SPI-1 deficient nontyphoidal Salmonella strains were isolated from infected humans and animals, indicating that SPI-1 is not required to cause enteropathogenesis and demonstrating the need for more in vivo-like models. Here, we utilized a previously characterized 3-D organotypic model of human intestinal epithelium to elucidate the role of all characterized Salmonella enterica T3SSs. Similar to in vivo reports, the Salmonella SPI-1 T3SS was not required to invade 3-D intestinal cells. Additionally, Salmonella strains carrying single (SPI-1 or SPI-2, double (SPI-1/2 and complete T3SS knockout (SPI-1/SPI-2: flhDC also invaded 3-D intestinal cells to wildtype levels. Invasion of wildtype and TTSS mutants was a Salmonella active process, whereas non-invasive bacterial strains, bacterial size beads, and heat-killed Salmonella did not invade 3-D cells. Wildtype and T3SS mutants did not preferentially target different cell types identified within the 3-D intestinal aggregates, including M-cells/M-like cells, enterocytes, or Paneth cells. Moreover, each T3SS was necessary for substantial intracellular bacterial replication within 3-D cells. Collectively, these results indicate that T3SSs are dispensable for Salmonella invasion into highly differentiated 3-D models of human intestinal epithelial cells, but are required for intracellular bacterial growth, paralleling in vivo infection observations and demonstrating the utility of these models in predicting in vivo-like pathogenic mechanisms.

Report of a case combining solitary Peutz-Jeghers polyp, colitis cystica profunda, and high-grade dysplasia of the epithelium of the colon.

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Papalampros, Alexandros; Vailas, Michail G; Sotiropoulou, Maria; Baili, Efstratia; Davakis, Spiridon; Moris, Demetrios; Felekouras, Evangelos; Deladetsima, Ioanna

2017-10-18

Colitis cystica profunda is a rare nonneoplastic disease defined by the presence of intramural cysts that contain mucus, usually situated in the rectosigmoid area, which can mimic various malignant lesions and polyps. Its etiology still remains not fully elucidated, and several mechanisms such as congenital, post-traumatic, and infectious have been implicated in the development of this rare entity. Herein, we describe a unique case of colitis cystica profunda in the setting of Peutz-Jeghers-type polyp of the sigmoid colon, associated with high-grade dysplasia of the overlying epithelium in a 48-year-old female patient, who presented to the emergency room with signs of intestinal obstruction. To the best of our insight, this is the first manifestation ever reported in the literature regarding the coexistence of solitary Peutz-Jeghers-type polyp, colitis cystica profunda, and high-grade dysplasia of the epithelium of the colon. The purpose of this case report is to highlight colitis cystica profunda and its clinical significance. An uncommon nonneoplastic entity, many times masquerading as malignant lesion of the rectosigmoid area of the colon. Clinicians and pathologists should be aware of this benign condition that is found incidentally postoperatively in patients undergoing colectomies, leading to unnecessary increase of morbidity and mortality in these patients, who otherwise could have been cured with conservative treatment only.

Food Derived Bioactive Peptides and Intestinal Barrier Function

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Olga Martínez-Augustin

2014-12-01

Full Text Available A wide range of food-derived bioactive peptides have been shown to exert health-promoting actions and are therefore considered functional foods or nutraceuticals. Some of these actions are related to the maintenance, reinforcement or repairment of the intestinal barrier function (IBF whose role is to selectively allow the absorption of water, nutrients and ions while preventing the influx of microorganisms from the intestinal lumen. Alterations in the IBF have been related to many disorders, such as inflammatory bowel disease or metabolic syndrome. Components of IBF are the intestinal epithelium, the mucus layer, secretory immunoglobulin A and cells of the innate and adaptive immune systems. Here we review the effects of food derived bioactive peptides on these IBF components. In vitro and in vivo effects, both in healthy and disease states, have been reviewed. Although limited, the available information indicates a potential for food-derived peptides to modify IBF and to contribute to disease treatment, but further research is needed to better isolate responsible peptides, and to help define their mode of action.

Intestinal surfactant permeation enhancers and their interaction with enterocyte cell membranes in a mucosal explant system

DEFF Research Database (Denmark)

Danielsen, E Michael; Hansen, Gert H

2017-01-01

Intestinal permeation enhancers (PEs) are agents aimed to improve oral delivery of therapeutic drugs with poor bioavailability. The main permeability barrier for oral delivery is the intestinal epithelium, and PEs act to increase the paracellular and/or transcellular passage of drugs. Transcellular...... for the fluorescent polar tracer lucifer yellow, but surprisingly, they all also blocked both constitutive -and receptor-mediated pathways of endocytosis from the brush border, indicating a complete arrest of apical membrane trafficking. At the ultrastructural level, the PEs caused longitudinal fusion of brush border...

Effects of Clostridium perfringens iota toxin in the small intestine of mice.

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Redondo, Leandro M; Redondo, Enzo A; Dailoff, Gabriela C; Leiva, Carlos L; Díaz-Carrasco, Juan M; Bruzzone, Octavio A; Cangelosi, Adriana; Geoghegan, Patricia; Fernandez-Miyakawa, Mariano E

2017-12-01

Iota toxin is a binary toxin solely produced by Clostridium perfringens type E strains, and is structurally related to CDT from C. difficile and CST from C. spiroforme. As type E causes hemorrhagic enteritis in cattle, it is usually assumed that associated diseases are mediated by iota toxin, although evidence in this regard has not been provided. In the present report, iota toxin intestinal effects were evaluated in vivo using a mouse model. Histological damage was observed in ileal loops treated with purified iota toxin after 4 h of incubation. Luminal iota toxin induced fluid accumulation in the small intestine in a dose dependent manner, as determined by the enteropooling and the intestinal loop assays. None of these changes were observed in the large intestine. These results suggest that C. perfringens iota toxin alters intestinal permeability, predominantly by inducing necrosis and degenerative changes in the mucosal epithelium of the small intestine, as well as changes in intestinal motility. The obtained results suggest a central role for iota toxin in the pathogenesis of C. perfringens type E hemorrhagic enteritis, and contribute to remark the importance of clostridial binary toxins in digestive diseases. Published by Elsevier Ltd.

Abnormal Nuclear Pore Formation Triggers Apoptosis in the Intestinal Epithelium of elys-Deficient Zebrafish

NARCIS (Netherlands)

de Jong-Curtain, Tanya A.; Parslow, Adam C.; Trotter, Andrew J.; Hall, Nathan E.; Verkade, Heather; Tabone, Tania; Christie, Elizabeth L.; Crowhurst, Meredith O.; Layton, Judith E.; Shepherd, Iain T.; Nixon, Susan J.; Parton, Robert G.; Zon, Leonard I.; Stainier, Didier Y. R.; Lieschke, Graham J.; Heath, Joan K.

Background & Aims: Zebrafish mutants generated by ethylnitrosourea-mutagenesis provide a powerful toot for dissecting the genetic regulation of developmental processes, including organogenesis. One zebrafish mutant, "flotte lotte" (flo), displays striking defects in intestinal, liver, pancreas, and

Intestinal glutathione: determinant of mucosal peroxide transport, metabolism, and oxidative susceptibility

International Nuclear Information System (INIS)

Aw, Tak Yee

2005-01-01

The intestine is a primary site of nutrient absorption and a critical defense barrier against dietary-derived mutagens, carcinogens, and oxidants. Accumulation of oxidants like peroxidized lipids in the gut lumen can contribute to impairment of mucosal metabolic pathways, enterocyte dysfunction independent of cell injury, and development of gut pathologies, such as inflammation and cancer. Despite this recognition, we know little of the pathways of intestinal transport, metabolism, and luminal disposition of dietary peroxides in vivo or of the underlying mechanisms of lipid peroxide-induced genesis of intestinal disease processes. This chapter summarizes our current understanding of the determinants of intestinal absorption and metabolism of peroxidized lipids. I will review experimental evidence from our laboratory and others (Table 1) supporting the pivotal role that glutathione (GSH) and reduced nicotinamide adenine dinucleotide phosphate (NADPH) play in mucosal transport and metabolism of lipid hydroperoxides and how reductant availability can be compromised under chronic stress such as hypoxia, and the influence of GSH on oxidative susceptibility, and redox contribution to genesis of gut disorders. The discussion is pertinent to understanding dietary lipid peroxides and GSH redox balance in intestinal physiology and pathophysiology and the significance of luminal GSH in preserving the integrity of the intestinal epithelium

Intestinal tumorigenesis is not affected by progesterone signaling in rodent models.

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Jarom Heijmans

Full Text Available Clinical data suggest that progestins have chemopreventive properties in the development of colorectal cancer. We set out to examine a potential protective effect of progestins and progesterone signaling on colon cancer development. In normal and neoplastic intestinal tissue, we found that the progesterone receptor (PR is not expressed. Expression was confined to sporadic mesenchymal cells. To analyze the influence of systemic progesterone receptor signaling, we crossed mice that lacked the progesterone receptor (PRKO to the Apc(Min/+ mouse, a model for spontaneous intestinal polyposis. PRKO-Apc(Min/+ mice exhibited no change in polyp number, size or localization compared to Apc(Min/+. To examine effects of progestins on the intestinal epithelium that are independent of the PR, we treated mice with MPA. We found no effects of either progesterone or MPA on gross intestinal morphology or epithelial proliferation. Also, in rats treated with MPA, injection with the carcinogen azoxymethane did not result in a difference in the number or size of aberrant crypt foci, a surrogate end-point for adenoma development. We conclude that expression of the progesterone receptor is limited to cells in the intestinal mesenchyme. We did not observe any effect of progesterone receptor signaling or of progestin treatment in rodent models of intestinal tumorigenesis.

Advanced three-dimensional culture of equine intestinal epithelial stem cells.

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Stewart, A Stieler; Freund, J M; Gonzalez, L M

2018-03-01

Intestinal epithelial stem cells are critical to epithelial repair following gastrointestinal injury. The culture of intestinal stem cells has quickly become a cornerstone of a vast number of new research endeavours that range from determining tissue viability to testing drug efficacy for humans. This study aims to describe the methods of equine stem cell culture and highlights the future benefits of these techniques for the advancement of equine medicine. To describe the isolation and culture of small intestinal stem cells into three-dimensional (3D) enteroids in horses without clinical gastrointestinal abnormalities. Descriptive study. Intestinal samples were collected by sharp dissection immediately after euthanasia. Intestinal crypts containing intestinal stem cells were dissociated from the underlying tissue layers, plated in a 3D matrix and supplemented with growth factors. After several days, resultant 3D enteroids were prepared for immunofluorescent imaging and polymerase chain reaction (PCR) analysis to detect and characterise specific cell types present. Intestinal crypts were cryopreserved immediately following collection and viability assessed. Intestinal crypts were successfully cultured and matured into 3D enteroids containing a lumen and budding structures. Immunofluorescence and PCR were used to confirm the existence of stem cells and all post mitotic, mature cell types, described to exist in the horse intestinal epithelium. Previously frozen crypts were successfully cultured following a freeze-thaw cycle. Tissues were all derived from normal horses. Application of this technique for the study of specific disease was not performed at this time. The successful culture of equine intestinal crypts into 3D "mini-guts" allows for in vitro studies of the equine intestine. Additionally, these results have relevance to future development of novel therapies that harness the regenerative potential of equine intestine in horses with gastrointestinal disease

The Inside Story of Shigella Invasion of Intestinal Epithelial Cells

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Carayol, Nathalie; Tran Van Nhieu, Guy

2013-01-01

As opposed to other invasive pathogens that reside into host cells in a parasitic mode, Shigella, the causative agent of bacillary dysentery, invades the colonic mucosa but does not penetrate further to survive into deeper tissues. Instead, Shigella invades, replicates, and disseminates within the colonic mucosa. Bacterial invasion and spreading in intestinal epithelium lead to the elicitation of inflammatory responses responsible for the tissue destruction and shedding in the environment for further infection of other hosts. In this article, we highlight specific features of the Shigella arsenal of virulence determinants injected by a type III secretion apparatus (T3SA) that point to the targeting of intestinal epithelial cells as a discrete route of invasion during the initial event of the infectious process. PMID:24086068

deltaNp63 has a role in maintaining epithelial integrity in airway epithelium.

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Arason, Ari Jon; Jonsdottir, Hulda R; Halldorsson, Skarphedinn; Benediktsdottir, Berglind Eva; Bergthorsson, Jon Thor; Ingthorsson, Saevar; Baldursson, Olafur; Sinha, Satrajit; Gudjonsson, Thorarinn; Magnusson, Magnus K

2014-01-01

The upper airways are lined with a pseudostratified bronchial epithelium that forms a barrier against unwanted substances in breathing air. The transcription factor p63, which is important for stratification of skin epithelium, has been shown to be expressed in basal cells of the lungs and its ΔN isoform is recognized as a key player in squamous cell lung cancer. However, the role of p63 in formation and maintenance of bronchial epithelia is largely unknown. The objective of the current study was to determine the expression pattern of the ΔN and TA isoforms of p63 and the role of p63 in the development and maintenance of pseudostratified lung epithelium in situ and in culture. We used a human bronchial epithelial cell line with basal cell characteristics (VA10) to model bronchial epithelium in an air-liquid interface culture (ALI) and performed a lentiviral-based silencing of p63 to characterize the functional and phenotypic consequences of p63 loss. We demonstrate that ΔNp63 is the major isoform in the human lung and its expression was exclusively found in the basal cells lining the basement membrane of the bronchial epithelium. Knockdown of p63 affected proliferation and migration of VA10 cells and facilitated cellular senescence. Expression of p63 is critical for epithelial repair as demonstrated by wound healing assays. Importantly, generation of pseudostratified VA10 epithelium in the ALI setup depended on p63 expression and goblet cell differentiation, which can be induced by IL-13 stimulation, was abolished by the p63 knockdown. After knockdown of p63 in primary bronchial epithelial cells they did not proliferate and showed marked senescence. We conclude that these results strongly implicate p63 in the formation and maintenance of differentiated pseudostratified bronchial epithelium.

Morphological and Functional Characterization of IL-12Rβ2 Chain on Intestinal Epithelial Cells: Implications for Local and Systemic Immunoregulation.

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Regoli, Mari; Man, Angela; Gicheva, Nadhezda; Dumont, Antonio; Ivory, Kamal; Pacini, Alessandra; Morucci, Gabriele; Branca, Jacopo J V; Lucattelli, Monica; Santosuosso, Ugo; Narbad, Arjan; Gulisano, Massimo; Bertelli, Eugenio; Nicoletti, Claudio

2018-01-01

that this event was not directly linked to the IEC-associated IL-12Rβ2 chain. We interpreted these data as showing that IEC-associated IL12Rβ2 is a component of the cytokine network operating at the interface between the intestinal epithelium and immune system that plays a role in immune regulation.

Lymphatic deletion of calcitonin receptor–like receptor exacerbates intestinal inflammation

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Davis, Reema B.; Kechele, Daniel O.; Blakeney, Elizabeth S.; Pawlak, John B.

2017-01-01

Lymphatics play a critical role in maintaining gastrointestinal homeostasis and in the absorption of dietary lipids, yet their roles in intestinal inflammation remain elusive. Given the increasing prevalence of inflammatory bowel disease, we investigated whether lymphatic vessels contribute to, or may be causative of, disease progression. We generated a mouse model with temporal and spatial deletion of the key lymphangiogenic receptor for the adrenomedullin peptide, calcitonin receptor–like receptor (Calcrl), and found that the loss of lymphatic Calcrl was sufficient to induce intestinal lymphangiectasia, characterized by dilated lacteals and protein-losing enteropathy. Upon indomethacin challenge, Calcrlfl/fl/Prox1-CreERT2 mice demonstrated persistent inflammation and failure to recover and thrive. The epithelium and crypts of Calcrlfl/fl/Prox1-CreERT2 mice exhibited exacerbated hallmarks of disease progression, and the lacteals demonstrated an inability to absorb lipids. Furthermore, we identified Calcrl/adrenomedullin signaling as an essential upstream regulator of the Notch pathway, previously shown to be critical for intestinal lacteal maintenance and junctional integrity. In conclusion, lymphatic insufficiency and lymphangiectasia caused by loss of lymphatic Calcrl exacerbates intestinal recovery following mucosal injury and underscores the importance of lymphatic function in promoting recovery from intestinal inflammation. PMID:28352669

Development and Characterization of a Human and Mouse Intestinal Epithelial Cell Monolayer Platform

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Kenji Kozuka

2017-12-01

Full Text Available Summary: We describe the development and characterization of a mouse and human epithelial cell monolayer platform of the small and large intestines, with a broad range of potential applications including the discovery and development of minimally systemic drug candidates. Culture conditions for each intestinal segment were optimized by correlating monolayer global gene expression with the corresponding tissue segment. The monolayers polarized, formed tight junctions, and contained a diversity of intestinal epithelial cell lineages. Ion transport phenotypes of monolayers from the proximal and distal colon and small intestine matched the known and unique physiology of these intestinal segments. The cultures secreted serotonin, GLP-1, and FGF19 and upregulated the epithelial sodium channel in response to known biologically active agents, suggesting intact secretory and absorptive functions. A screen of over 2,000 pharmacologically active compounds for inhibition of potassium ion transport in the mouse distal colon cultures led to the identification of a tool compound. : Siegel and colleagues describe their development of a human and mouse intestinal epithelial cell monolayer platform that maintains the cellular, molecular, and functional characteristics of tissue for each intestinal segment. They demonstrate the platform's application to drug discovery by screening a library of over 2,000 compounds to identify an inhibitor of potassium ion transport in the mouse distal colon. Keywords: intestinal epithelium, organoids, monolayer, colon, small intestine, phenotype screening assays, enteroid, colonoid

Reparo de esôfago cervical de cães com segmento intestinal livre autólogo desprovido de epitélio e de lâmina própria da túnica mucosa Canine cervical esophagus repair using of free autograft intestinal segment without epithelium and lamina propria of the mucosa

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Patrícia Maria Coletto Freitas

2002-06-01

Full Text Available Doze cães foram separados em dois grupos de igual número e submetidos à remoção de um retalho de 3,0 x 3,5cm do esôfago cervical. A abertura foi ocluída com enxerto de segmento intestinal livre autólogo desprovido de epitélio e lâmina própria da túnica mucosa, com pontos simples separados por fio poliglactina 910. Os animais do grupo 1 foram observados durante 15 dias de pós-operatório, e os do grupo 2, durante 30 dias. Observou-se epitelização e discreta estenose no local do enxerto com invasão de tecido conjuntivo denso rico em fibras colágenas. O enxerto de segmento intestinal livre autólogo foi eficiente no reparo de rupturas do esôfago cervical de cães.Twelve dogs were allocated in two groups with same number of animals and submitted to removal of a 3.0 x 3.5cm piece of the cervical esophagus. The incision was occluded with a autograft of free intestinal segment without epithelium and lamina propria of the mucosa, with separate simples points using poliglactina 910 line. Animals of the group 1 were observed for 15 days post-surgery, and the animals from group 2, for 30 days. Epithelization and discreet stenosis in the place of the graft with invasion of dense conjunctive tissue, rich in collagen fibers was noticed. The autograft free intestinal segment was efficient in the repair of ruptures in the cervical segment of the canine esophagous.

Progenitor Epithelium

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Marty-Santos, Leilani

2015-01-01

Insulin-producing β cells within the vertebrate fetal pancreas acquire their fate in a step-wise manner. Whereas the intrinsic factors dictating the transcriptional or epigenetic status of pancreatic lineages have been intensely examined, less is known about cell–cell interactions that might constitute a niche for the developing β cell lineage. It is becoming increasingly clear that understanding and recapitulating these steps may instruct in vitro differentiation of embryonic stem cells and/or therapeutic regeneration. Indeed, directed differentiation techniques have improved since transitioning from 2D to 3D cultures, suggesting that the 3D microenvironment in which β cells are born is critical. However, to date, it remains unknown whether the changing architecture of the pancreatic epithelium impacts the fate of cells therein. An emerging challenge in the field is to elucidate how progenitors are allocated during key events, such as the stratification and subsequent resolution of the pre-pancreatic epithelium, as well as the formation of lumens and branches. Here, we assess the progenitor epithelium and examine how it might influence the emergence of pancreatic multipotent progenitors (MPCs), which give rise to β cells and other pancreatic lineages. PMID:26216134

Dysfunctions at human intestinal barrier by water-borne protozoan parasites: lessons from cultured human fully differentiated colon cancer cell lines.

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Liévin-Le Moal, Vanessa

2013-06-01

Some water-borne protozoan parasites induce diseases through their membrane-associated functional structures and virulence factors that hijack the host cellular molecules and signalling pathways leading to structural and functional lesions in the intestinal barrier. In this Microreview we analyse the insights on the mechanisms of pathogenesis of Entamoeba intestinalis, Giardia and Cryptosporidium observed in the human colon carcinoma fully differentiated colon cancer cell lines, cell subpopulations and clones expressing the structural and functional characteristics of highly specialized fully differentiated epithelial cells lining the intestinal epithelium and mimicking structurally and functionally an intestinal barrier. © 2013 John Wiley & Sons Ltd.

Defining new criteria for selection of cell-based intestinal models using publicly available databases

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Christensen Jon

2012-06-01

Full Text Available Abstract Background The criteria for choosing relevant cell lines among a vast panel of available intestinal-derived lines exhibiting a wide range of functional properties are still ill-defined. The objective of this study was, therefore, to establish objective criteria for choosing relevant cell lines to assess their appropriateness as tumor models as well as for drug absorption studies. Results We made use of publicly available expression signatures and cell based functional assays to delineate differences between various intestinal colon carcinoma cell lines and normal intestinal epithelium. We have compared a panel of intestinal cell lines with patient-derived normal and tumor epithelium and classified them according to traits relating to oncogenic pathway activity, epithelial-mesenchymal transition (EMT and stemness, migratory properties, proliferative activity, transporter expression profiles and chemosensitivity. For example, SW480 represent an EMT-high, migratory phenotype and scored highest in terms of signatures associated to worse overall survival and higher risk of recurrence based on patient derived databases. On the other hand, differentiated HT29 and T84 cells showed gene expression patterns closest to tumor bulk derived cells. Regarding drug absorption, we confirmed that differentiated Caco-2 cells are the model of choice for active uptake studies in the small intestine. Regarding chemosensitivity we were unable to confirm a recently proposed association of chemo-resistance with EMT traits. However, a novel signature was identified through mining of NCI60 GI50 values that allowed to rank the panel of intestinal cell lines according to their drug responsiveness to commonly used chemotherapeutics. Conclusions This study presents a straightforward strategy to exploit publicly available gene expression data to guide the choice of cell-based models. While this approach does not overcome the major limitations of such models

Casein kinase 1-epsilon or 1-delta required for Wnt-mediated intestinal stem cell maintenance.

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Morgenstern, Yael; Das Adhikari, Upasana; Ayyash, Muneef; Elyada, Ela; Tóth, Beáta; Moor, Andreas; Itzkovitz, Shalev; Ben-Neriah, Yinon

2017-10-16

The intestinal epithelium holds an immense regenerative capacity mobilized by intestinal stem cells (ISCs), much of it supported by Wnt pathway activation. Several unique regulatory mechanisms ensuring optimal levels of Wnt signaling have been recognized in ISCs. Here, we identify another Wnt signaling amplifier, CKIε, which is specifically upregulated in ISCs and is essential for ISC maintenance, especially in the absence of its close isoform CKIδ. Co-ablation of CKIδ/ε in the mouse gut epithelium results in rapid ISC elimination, with subsequent growth arrest, crypt-villous shrinking, and rapid mouse death. Unexpectedly, Wnt activation is preserved in all CKIδ/ε-deficient enterocyte populations, with the exception of Lgr5 + ISCs, which exhibit Dvl2-dependent Wnt signaling attenuation. CKIδ/ε-depleted gut organoids cease proliferating and die rapidly, yet survive and resume self-renewal upon reconstitution of Dvl2 expression. Our study underscores a unique regulation mode of the Wnt pathway in ISCs, possibly providing new means of stem cell enrichment for regenerative medicine. © 2017 The Authors.

Central nervous system regulation of intestinal lipid and lipoprotein metabolism.

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Farr, Sarah; Taher, Jennifer; Adeli, Khosrow

2016-02-01

In response to nutrient availability, the small intestine and brain closely communicate to modulate energy homeostasis and metabolism. The gut-brain axis involves complex nutrient sensing mechanisms and an integration of neuronal and hormonal signaling. This review summarizes recent evidence implicating the gut-brain axis in regulating lipoprotein metabolism, with potential implications for the dyslipidemia of insulin resistant states. The intestine and brain possess distinct mechanisms for sensing lipid availability, which triggers subsequent regulation of feeding, glucose homeostasis, and adipose tissue metabolism. More recently, central receptors, neuropeptides, and gut hormones that communicate with the brain have been shown to modulate hepatic and intestinal lipoprotein metabolism via parasympathetic and sympathetic signaling. Gut-derived glucagon-like peptides appear to be particularly important in modulating the intestinal secretion of chylomicron particles via a novel brain-gut axis. Dysregulation of these pathways may contribute to postprandial diabetic dyslipidemia. Emerging evidence implicates the central and enteric nervous systems in controlling many aspects of lipid and lipoprotein metabolism. Bidirectional communication between the gut and brain involving neuronal pathways and gut peptides is critical for regulating feeding and metabolism, and forms a neuroendocrine circuit to modulate dietary fat absorption and intestinal production of atherogenic chylomicron particles.

Intestinal crosstalk: a new paradigm for understanding the gut as the "motor" of critical illness.

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Clark, Jessica A; Coopersmith, Craig M

2007-10-01

For more than 20 years, the gut has been hypothesized to be the "motor" of multiple organ dysfunction syndrome. As critical care research has evolved, there have been multiple mechanisms by which the gastrointestinal tract has been proposed to drive systemic inflammation. Many of these disparate mechanisms have proved to be important in the origin and propagation of critical illness. However, this has led to an unusual situation where investigators describing the gut as a "motor" revving the systemic inflammatory response syndrome are frequently describing wholly different processes to support their claim (i.e., increased apoptosis, altered tight junctions, translocation, cytokine production, crosstalk with commensal bacteria, etc). The purpose of this review is to present a unifying theory as to how the gut drives critical illness. Although the gastrointestinal tract is frequently described simply as "the gut," it is actually made up of (1) an epithelium; (2) a diverse and robust immune arm, which contains most of the immune cells in the body; and (3) the commensal bacteria, which contain more cells than are present in the entire host organism. We propose that the intestinal epithelium, the intestinal immune system, and the intestine's endogenous bacteria all play vital roles driving multiple organ dysfunction syndrome, and the complex crosstalk between these three interrelated portions of the gastrointestinal tract is what cumulatively makes the gut a "motor" of critical illness.

Signal transduction pathways participating in homeostasis and malignant transformation of the intestinal tissue

Czech Academy of Sciences Publication Activity Database

Krausová, Michaela; Kořínek, Vladimír

2012-01-01

Roč. 59, č. 6 (2012), s. 708-718 ISSN 0028-2685 R&D Projects: GA ČR GAP305/11/1780; GA ČR GAP305/12/2347; GA ČR GAP304/11/1252; GA ČR GD204/09/H058 Keywords : colorectal cancer * epithelium * gut * intestine * mouse models * stem cells Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 1.574, year: 2012

Fecal markers of intestinal inflammation and intestinal permeability are elevated in Parkinson's disease.

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Schwiertz, Andreas; Spiegel, Jörg; Dillmann, Ulrich; Grundmann, David; Bürmann, Jan; Faßbender, Klaus; Schäfer, Karl-Herbert; Unger, Marcus M

2018-02-12

Intestinal inflammation and increased intestinal permeability (both possibly fueled by dysbiosis) have been suggested to be implicated in the multifactorial pathogenesis of Parkinson's disease (PD). The objective of the current study was to investigate whether fecal markers of inflammation and impaired intestinal barrier function corroborate this pathogenic aspect of PD. In a case-control study, we quantitatively analyzed established fecal markers of intestinal inflammation (calprotectin and lactoferrin) and fecal markers of intestinal permeability (alpha-1-antitrypsin and zonulin) in PD patients (n = 34) and controls (n = 28, group-matched for age) by enzyme-linked immunosorbent assay. The study design controlled for potential confounding factors. Calprotectin, a fecal marker of intestinal inflammation, and two fecal markers of increased intestinal permeability (alpha-1-antitrypsin and zonulin) were significantly elevated in PD patients compared to age-matched controls. Lactoferrin, as a second fecal marker of intestinal inflammation, showed a non-significant trend towards elevated concentrations in PD patients. None of the four fecal markers correlated with disease severity, PD subtype, dopaminergic therapy, or presence of constipation. Fecal markers reflecting intestinal inflammation and increased intestinal permeability have been primarily investigated in inflammatory bowel disease so far. Our data indicate that calprotectin, alpha-1-antitrypsin and zonulin could be useful non-invasive markers in PD as well. Even though these markers are not disease-specific, they corroborate the hypothesis of an intestinal inflammation as contributing factor in the pathogenesis of PD. Further investigations are needed to determine whether calprotectin, alpha-1-antitrypsin and zonulin can be used to define PD subgroups and to monitor the effect of interventions in PD. Copyright © 2018 Elsevier Ltd. All rights reserved.

Always one step ahead: How pathogenic bacteria use the type III secretion system to manipulate the intestinal mucosal immune system

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Marchès Olivier

2011-05-01

Full Text Available Abstract The intestinal immune system and the epithelium are the first line of defense in the gut. Constantly exposed to microorganisms from the environment, the gut has complex defense mechanisms to prevent infections, as well as regulatory pathways to tolerate commensal bacteria and food antigens. Intestinal pathogens have developed strategies to regulate intestinal immunity and inflammation in order to establish or prolong infection. The organisms that employ a type III secretion system use a molecular syringe to deliver effector proteins into the cytoplasm of host cells. These effectors target the host cell cytoskeleton, cell organelles and signaling pathways. This review addresses the multiple mechanisms by which the type III secretion system targets the intestinal immune response, with a special focus on pathogenic E. coli.

Compartmentalised expression of meprin in small intestinal mucosa: enhanced expression in lamina propria in coeliac disease.

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Lottaz, Daniel; Buri, Caroline; Monteleone, Giovanni; Rösmann, Sandra; Macdonald, Thomas T; Sanderson, Ian R; Sterchi, Erwin E

2007-03-01

Epithelial cells in the human small intestine express meprin, an astacin-like metalloprotease, which accumulates normally at the brush border membrane and in the gut lumen. Therefore, meprin is targeted towards luminal components. In coeliac disease patients, peptides from ingested cereals trigger mucosal inflammation in the small intestine, disrupting epithelial cell differentiation and function. Using in situ hybridisation on duodenal tissue sections, we observed a marked shift of meprin mRNA expression from epithelial cells, the predominant expression site in normal mucosa, to lamina propria leukocytes in coeliac disease. Meprin thereby gains access to the substrate repertoire present beneath the epithelium.

The Structure of Urethral Epithelium in Merinos Lambs

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Vasile RUS

2018-05-01

Full Text Available The aim of this study was to investigate by histological techniques the structure of urethral epithelium in lambs. In this study, we harvested several fragments (prostatic, membranous and cavernous from urethra from 5 merino’s lambs of 3 months old. The first anatomical segment, the prostatic urethra, is lined by a urinary epithelium. The intermediary layer of this epithelium is formed of 5-6 rows of oval cells. The second segment of urethra has the same type of epithelium but the intermediary layer is formed of 6-7 rows of oval cells. In the last anatomical segment, the penile urethra, the epithelium is the same, but the intermediary layer has 3-4 rows of oval cells. In lambs, the urethra is lined by urinary epithelium. The urethral epithelium does not have the same thickness in all segments. The thinner epithelium it is in the cavernous urethra, the ticker is the membranous urethra.

Osmoregulation and epithelial water transport: lessons from the intestine of marine teleost fish.

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Whittamore, Jonathan M

2012-01-01

For teleost fish living in seawater, drinking the surrounding medium is necessary to avoid dehydration. This is a key component of their osmoregulatory strategy presenting the challenge of excreting excess salts while achieving a net retention of water. The intestine has an established role in osmoregulation, and its ability to effectively absorb fluid is crucial to compensating for water losses to the hyperosmotic environment. Despite this, the potential for the teleost intestine to serve as a comparative model for detailed, integrative experimental studies on epithelial water transport has so far gone largely untapped. The following review aims to present an assessment of the teleost intestine as a fluid-transporting epithelium. Beginning with a brief overview of marine teleost osmoregulation, emphasis shifts to the processing of ingested seawater by the gastrointestinal tract and the characteristics of intestinal ion and fluid transport. Particular attention is given to acid-base transfers by the intestine, specifically bicarbonate secretion, which creates the distinctly alkaline gut fluids responsible for the formation of solid calcium carbonate precipitates. The respective contributions of these unique features to intestinal fluid absorption, alongside other recognised ion transport processes, are then subsequently considered within the wider context of the classic physiological problem of epithelial water transport.

Human Primary Intestinal Epithelial Cells as an Improved In Vitro Model for Cryptosporidium parvum Infection

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Cabada, Miguel M.; Nichols, Joan; Gomez, Guillermo; White, A. Clinton

2013-01-01

The study of human intestinal pathogens has been limited by the lack of methods for the long-term culture of primary human intestinal epithelial cells (PECs). The development of infection models with PECs would allow a better understanding of host-parasite interactions. The objective of this study was to develop a novel method for prolonged in vitro cultivation of PECs that can be used to study Cryptosporidium infection. We isolated intact crypts from human intestines removed during weight loss surgery. The fragments of intestinal layers were cultivated with culture medium supplemented with growth factors and antiapoptotic molecules. After 7 days, the PECs formed self-regenerating cell clusters, forming villi that resemble intestinal epithelium. The PECs proliferated and remained viable for at least 60 days. The cells expressed markers for intestinal stem cells, epithelial cells, and mature enterocytes. The PECs were infected with Cryptosporidium. In contrast to older models in which parasite numbers decay, the burden of parasites increased for >120 h. In summary, we describe here a novel method for the cultivation of self-regenerating human epithelial cells from small intestinal crypts, which contain both intestinal stem cells and mature villus cells. We present data that suggest these cells support Cryptosporidium better than existing cell lines. PECs should provide an improved tool for studying host-parasite interactions involving Cryptosporidium and other intestinal pathogens. PMID:23509153

The Msi Family of RNA-Binding Proteins Function Redundantly as Intestinal Oncoproteins

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Ning Li

2015-12-01

Full Text Available Members of the Msi family of RNA-binding proteins have recently emerged as potent oncoproteins in a range of malignancies. MSI2 is highly expressed in hematopoietic cancers, where it is required for disease maintenance. In contrast to the hematopoietic system, colorectal cancers can express both Msi family members, MSI1 and MSI2. Here, we demonstrate that, in the intestinal epithelium, Msi1 and Msi2 have analogous oncogenic effects. Further, comparison of Msi1/2-induced gene expression programs and transcriptome-wide analyses of Msi1/2-RNA-binding targets reveal significant functional overlap, including induction of the PDK-Akt-mTORC1 axis. Ultimately, we demonstrate that concomitant loss of function of both MSI family members is sufficient to abrogate the growth of human colorectal cancer cells, and Msi gene deletion inhibits tumorigenesis in several mouse models of intestinal cancer. Our findings demonstrate that MSI1 and MSI2 act as functionally redundant oncoproteins required for the ontogeny of intestinal cancers.

Mechanisms of decreased intestinal epithelial proliferation and increased apoptosis in murine acute lung injury.

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Husain, Kareem D; Stromberg, Paul E; Woolsey, Cheryl A; Turnbull, Isaiah R; Dunne, W Michael; Javadi, Pardis; Buchman, Timothy G; Karl, Irene E; Hotchkiss, Richard S; Coopersmith, Craig M

2005-10-01

The aim of this study was to determine the effects of acute lung injury on the gut epithelium and examine mechanisms underlying changes in crypt proliferation and apoptosis. The relationship between severity and timing of lung injury to intestinal pathology was also examined. Randomized, controlled study. University research laboratory. Genetically inbred mice. Following induction of acute lung injury, gut epithelial proliferation and apoptosis were assessed in a) C3H/HeN wild-type and C3H/HeJ mice, which lack functional Toll-like receptor 4 (n = 17); b) C57Bl/6 mice that received monoclonal anti-tumor necrosis factor-alpha or control antibody (n = 22); and c) C57Bl/6 wild-type and transgenic mice that overexpress Bcl-2 in their gut epithelium (n = 21). Intestinal epithelial proliferation and death were also examined in animals with differing degrees of lung inflammation (n = 24) as well as in a time course analysis following a fixed injury (n = 18). Acute lung injury caused decreased proliferation and increased apoptosis in crypt epithelial cells in all animals studied. C3H/HeJ mice had higher levels of proliferation than C3H/HeN animals without additional changes in apoptosis. Anti-tumor necrosis factor-alpha antibody had no effect on gut epithelial proliferation or death. Overexpression of Bcl-2 did not change proliferation despite decreasing gut apoptosis. Proliferation and apoptosis were not correlated to severity of lung injury, as gut alterations were lost in mice with more severe acute lung injury. Changes in both gut epithelial proliferation and death were apparent within 12 hrs, but proliferation was decreased 36 hrs following acute lung injury while apoptosis returned to normal. Acute lung injury causes disparate effects on crypt proliferation and apoptosis, which occur, at least in part, through differing mechanisms involving Toll-like receptor 4 and Bcl-2. Severity of lung injury does not correlate with perturbations in proliferation or death in the

Childhood malnutrition and the intestinal microbiome.

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Kane, Anne V; Dinh, Duy M; Ward, Honorine D

2015-01-01

Malnutrition contributes to almost half of all deaths in children under the age of 5 y, particularly those who live in resource-constrained areas. Those who survive frequently suffer from long-term sequelae including growth failure and neurodevelopmental impairment. Malnutrition is part of a vicious cycle of impaired immunity, recurrent infections, and worsening malnutrition. Recently, alterations in the gut microbiome have also been strongly implicated in childhood malnutrition. It has been suggested that malnutrition may delay the normal development of the gut microbiota in early childhood or force it toward an altered composition that lacks the required functions for healthy growth and/or increases the risk for intestinal inflammation. This review addresses our current understanding of the beneficial contributions of gut microbiota to human nutrition (and conversely the potential role of changes in that community to malnutrition), the process of acquiring an intestinal microbiome, potential influences of malnutrition on the developing microbiota, and the evidence directly linking alterations in the intestinal microbiome to childhood malnutrition. We review recent studies on the association between alterations in the intestinal microbiome and early childhood malnutrition and discuss them in the context of implications for intervention or prevention of the devastation caused by malnutrition.

Intestinal enzyme distribution after supralethal irradiation

Energy Technology Data Exchange (ETDEWEB)

Becciolini, A; Gerber, G B; Buracchi, A; Deroo, J [Florence Univ. (Italy). Istituto di Radiologia; Centre d' Etude de l' Energie Nucleaire, Mol (Belgium). Dept. de Radiobiologie)

1977-07-01

The activity of some intestinal enzymes has been studied after 2 kR irradiation. Brush border enzymes, maltase and leucineaminopeptidase (LAP) show an increase 20 hours after irradiation, while after 72 hours their activities are reduced to very low levels. Lysosomal enzymes show a completely different behaviour: acid phosphatase activity increases only 72 hours after irradiation, whereas ..beta.. glucuronidase increases significantly after 20 hours and reaches values two or three times higher than controls after 72 hours. The histologic picture at the first interval after irradiation shows gross alterations in the crypt region, but the villi appear nearly normal. Seventy-two hours after irradiation the whole epithelium is affected and very numerous leukocytes are present in the stroma.

Wnt, RSPO and Hippo Signalling in the Intestine and Intestinal Stem Cells.

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Kriz, Vitezslav; Korinek, Vladimir

2018-01-08

In this review, we address aspects of Wnt, R-Spondin (RSPO) and Hippo signalling, in both healthy and transformed intestinal epithelium. In intestinal stem cells (ISCs), the Wnt pathway is essential for intestinal crypt formation and renewal, whereas RSPO-mediated signalling mainly affects ISC numbers. In human colorectal cancer (CRC), aberrant Wnt signalling is the driving mechanism initiating this type of neoplasia. The signalling role of the RSPO-binding transmembrane proteins, the leucine-rich-repeat-containing G-protein-coupled receptors (LGRs), is possibly more pleiotropic and not only limited to the enhancement of Wnt signalling. There is growing evidence for multiple crosstalk between Hippo and Wnt/β-catenin signalling. In the ON state, Hippo signalling results in serine/threonine phosphorylation of Yes-associated protein (YAP1) and tafazzin (TAZ), promoting formation of the β-catenin destruction complex. In contrast, YAP1 or TAZ dephosphorylation (and YAP1 methylation) results in β-catenin destruction complex deactivation and β-catenin nuclear localization. In the Hippo OFF state, YAP1 and TAZ are engaged with the nuclear β-catenin and participate in the β-catenin-dependent transcription program. Interestingly, YAP1/TAZ are dispensable for intestinal homeostasis; however, upon Wnt pathway hyperactivation, the proteins together with TEA domain (TEAD) transcription factors drive the transcriptional program essential for intestinal cell transformation. In addition, in many CRC cells, YAP1 phosphorylation by YES proto-oncogene 1 tyrosine kinase (YES1) leads to the formation of a transcriptional complex that includes YAP1, β-catenin and T-box 5 (TBX5) DNA-binding protein. YAP1/β-catenin/T-box 5-mediated transcription is necessary for CRC cell proliferation and survival. Interestingly, dishevelled (DVL) appears to be an important mediator involved in both Wnt and Hippo (YAP1/TAZ) signalling and some of the DVL functions were assigned to the nuclear DVL

Effects of saponins and glycoalkaloids on the permeability and viability of mammalian intestinal cells and on the integrity of tissue preparations in vitro

NARCIS (Netherlands)

Gee, J.M.; Wortley, G.M.; Johnson, I.T.; Price, K.R.; Rutten, A.A.J.J.L.; Houben, G.F.; Penninks, A.H.

1996-01-01

The effects of potato and tomato glycoalkaloids and a saponin mixture from Gypsophila were investigated in cytotoxicity studies (neutral red uptake, mitochondrial MTT reduction and release of lactate dehydrogenase), using cultured cell lines of rat and human intestinal mucosal epithelium.

Culture of human intestinal epithelial cell using the dissociating enzyme thermolysin and endothelin-3

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Z. Liu

2010-05-01

Full Text Available Epithelium, a highly dynamic system, plays a key role in the homeostasis of the intestine. However, thus far a human intestinal epithelial cell line has not been established in many countries. Fetal tissue was selected to generate viable cell cultures for its sterile condition, effective generation, and differentiated character. The purpose of the present study was to culture human intestinal epithelial cells by a relatively simple method. Thermolysin was added to improve the yield of epithelial cells, while endothelin-3 was added to stimulate their growth. By adding endothelin-3, the achievement ratio (viable cell cultures/total cultures was enhanced to 60% of a total of 10 cultures (initiated from 8 distinct fetal small intestines, allowing the generation of viable epithelial cell cultures. Western blot, real-time PCR and immunofluorescent staining showed that cytokeratins 8, 18 and mouse intestinal mucosa-1/39 had high expression levels in human intestinal epithelial cells. Differentiated markers such as sucrase-isomaltase, aminopeptidase N and dipeptidylpeptidase IV also showed high expression levels in human intestinal epithelial cells. Differentiated human intestinal epithelial cells, with the expression of surface markers (cytokeratins 8, 18 and mouse intestinal mucosa-1/39 and secretion of cytokines (sucrase-isomaltase, aminopeptidase N and dipeptidylpeptidase IV, may be cultured by the thermolysin and endothelin-3 method and maintained for at least 20 passages. This is relatively simple, requiring no sophisticated techniques or instruments, and may have a number of varied applications.

Proteomic profiling of a mouse model of acute intestinal Apc deletion leads to identification of potential novel biomarkers of human colorectal cancer (CRC).

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Hammoudi, Abeer; Song, Fei; Reed, Karen R; Jenkins, Rosalind E; Meniel, Valerie S; Watson, Alastair J M; Pritchard, D Mark; Clarke, Alan R; Jenkins, John R

2013-10-25

Colorectal cancer (CRC) is the fourth most common cause of cancer-related death worldwide. Accurate non-invasive screening for CRC would greatly enhance a population's health. Adenomatous polyposis coli (Apc) gene mutations commonly occur in human colorectal adenomas and carcinomas, leading to Wnt signalling pathway activation. Acute conditional transgenic deletion of Apc in murine intestinal epithelium (AhCre(+)Apc(fl)(/)(fl)) causes phenotypic changes similar to those found during colorectal tumourigenesis. This study comprised a proteomic analysis of murine small intestinal epithelial cells following acute Apc deletion to identify proteins that show altered expression during human colorectal carcinogenesis, thus identifying proteins that may prove clinically useful as blood/serum biomarkers of colorectal neoplasia. Eighty-one proteins showed significantly increased expression following iTRAQ analysis, and validation of nine of these by Ingenuity Pathaway Analysis showed they could be detected in blood or serum. Expression was assessed in AhCre(+)Apc(fl)(/)(fl) small intestinal epithelium by immunohistochemistry, western blot and quantitative real-time PCR; increased nucelolin concentrations were also detected in the serum of AhCre(+)Apc(fl)(/)(fl) and Apc(Min)(/)(+) mice by ELISA. Six proteins; heat shock 60kDa protein 1, Nucleolin, Prohibitin, Cytokeratin 18, Ribosomal protein L6 and DEAD (Asp-Glu-Ala-Asp) box polypeptide 5,were selected for further investigation. Increased expression of 4 of these was confirmed in human CRC by qPCR. In conclusion, several novel candidate biomarkers have been identified from analysis of transgenic mice in which the Apc gene was deleted in the intestinal epithelium that also showed increased expression in human CRC. Some of these warrant further investigation as potential serum-based biomarkers of human CRC. Copyright © 2013 Elsevier Inc. All rights reserved.

Xenobiotic effects on intestinal stem cell proliferation in adult honey bee (Apis mellifera L) workers.

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Forkpah, Cordelia; Dixon, Luke R; Fahrbach, Susan E; Rueppell, Olav

2014-01-01

The causes of the current global decline in honey bee health are unknown. One major group of hypotheses invokes the pesticides and other xenobiotics to which this important pollinator species is often exposed. Most studies have focused on mortality or behavioral deficiencies in exposed honey bees while neglecting other biological functions and target organs. The midgut epithelium of honey bees presents an important interface between the insect and its environment. It is maintained by proliferation of intestinal stem cells throughout the adult life of honey bees. We used caged honey bees to test multiple xenobiotics for effects on the replicative activity of the intestinal stem cells under laboratory conditions. Most of the tested compounds did not alter the replicative activity of intestinal stem cells. However, colchicine, methoxyfenozide, tetracycline, and a combination of coumaphos and tau-fluvalinate significantly affected proliferation rate. All substances except methoxyfenozide decreased proliferation rate. Thus, the results indicate that some xenobiotics frequently used in apiculture and known to accumulate in honey bee hives may have hitherto unknown physiological effects. The nutritional status and the susceptibility to pathogens of honey bees could be compromised by the impacts of xenobiotics on the maintenance of the midgut epithelium. This study contributes to a growing body of evidence that more comprehensive testing of xenobiotics may be required before novel or existing compounds can be considered safe for honey bees and other non-target species.

Metamorphosis of the Drosophila visceral musculature and its role in intestinal morphogenesis and stem cell formation.

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Aghajanian, Patrick; Takashima, Shigeo; Paul, Manash; Younossi-Hartenstein, Amelia; Hartenstein, Volker

2016-12-01

The visceral musculature of the Drosophila intestine plays important roles in digestion as well as development. Detailed studies investigating the embryonic development of the visceral muscle exist; comparatively little is known about postembryonic development and metamorphosis of this tissue. In this study we have combined the use of specific markers with electron microscopy to follow the formation of the adult visceral musculature and its involvement in gut development during metamorphosis. Unlike the adult somatic musculature, which is derived from a pool of undifferentiated myoblasts, the visceral musculature of the adult is a direct descendant of the larval fibers, as shown by activating a lineage tracing construct in the larval muscle and obtaining labeled visceral fibers in the adult. However, visceral muscles undergo a phase of remodeling that coincides with the metamorphosis of the intestinal epithelium. During the first day following puparium formation, both circular and longitudinal syncytial fibers dedifferentiate, losing their myofibrils and extracellular matrix, and dissociating into mononuclear cells ("secondary myoblasts"). Towards the end of the second day, this process is reversed, and between 48 and 72h after puparium formation, a structurally fully differentiated adult muscle layer has formed. We could not obtain evidence that cells apart from the dedifferentiated larval visceral muscle contributed to the adult muscle, nor does it appear that the number of adult fibers (or nuclei per fiber) is increased over that of the larva by proliferation. In contrast to the musculature, the intestinal epithelium is completely renewed during metamorphosis. The adult midgut epithelium rapidly expands over the larval layer during the first few hours after puparium formation; in case of the hindgut, replacement takes longer, and proceeds by the gradual caudad extension of a proliferating growth zone, the hindgut proliferation zone (HPZ). The subsequent

Abortive Intestinal Infection With an Escherichia coli-Shigella flexneri Hybrid Strain

Science.gov (United States)

Formal, Samuel B.; LaBrec, E. H.; Kent, T. H.; Falkow, S.

1965-01-01

Formal, Samuel B., (Walter Reed Army Institute of Research, Washington, D.C.), E. H. LaBrec, T. H. Kent, and S. Falkow. Abortive intestinal infection with an Escherichia coli-Shigella flexneri hybrid strain. J. Bacteriol. 89:1374–1382. 1965.—The mechanism of the apparent loss of virulence of an Escherichia coli-Shigella flexneri hybrid strain was studied. The parent Shigella strain caused a fatal enteric infection when fed to starved guinea pigs, and signs of dysentery followed its oral administration to monkeys. The hybrid strain failed to produce any apparent symptoms when fed to either of these species. The parent strain was shown to invade the intestinal mucosa of starved guinea pigs. This caused a severe inflammatory reaction in the lamina propria, which progressed to ulceration of the intestinal epithelium and resulted in death of the animal. The hybrid strain also invaded the intestinal mucosa and produced an inflammatory reaction. In this case, the inflammatory reaction subsided, the intestine returned to normal within 4 days after challenge, and the animal survived. Both fluorescent-antibody techniques and in vivo growth studies have shown that the hybrid strain can not maintain itself in the intestinal mucosa. Preliminary studies have indicated that a similar situation also exists in the monkey. It is concluded that the virulence of dysentery bacilli rests not only in the capacity to reach the lamina propria, but also in the ability to multiply in this region. Images PMID:14293011

Commensal-pathogen interactions in the intestinal tract

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Reynolds, Lisa A; Smith, Katherine A; Filbey, Kara J; Harcus, Yvonne; Hewitson, James P; Redpath, Stephen A; Valdez, Yanet; Yebra, María J; Finlay, B Brett; Maizels, Rick M

2016-01-01

The intestinal microbiota are pivotal in determining the developmental, metabolic and immunological status of the mammalian host. However, the intestinal tract may also accommodate pathogenic organisms, including helminth parasites which are highly prevalent in most tropical countries. Both microbes and helminths must evade or manipulate the host immune system to reside in the intestinal environment, yet whether they influence each other’s persistence in the host remains unknown. We now show that abundance of Lactobacillus bacteria correlates positively with infection with the mouse intestinal nematode, Heligmosomoides polygyrus, as well as with heightened regulatory T cell (Treg) and Th17 responses. Moreover, H. polygyrus raises Lactobacillus species abundance in the duodenum of C57BL/6 mice, which are highly susceptible to H. polygyrus infection, but not in BALB/c mice, which are relatively resistant. Sequencing of samples at the bacterial gyrB locus identified the principal Lactobacillus species as L. taiwanensis, a previously characterized rodent commensal. Experimental administration of L. taiwanensis to BALB/c mice elevates regulatory T cell frequencies and results in greater helminth establishment, demonstrating a causal relationship in which commensal bacteria promote infection with an intestinal parasite and implicating a bacterially-induced expansion of Tregs as a mechanism of greater helminth susceptibility. The discovery of this tripartite interaction between host, bacteria and parasite has important implications for both antibiotic and anthelmintic use in endemic human populations. PMID:25144609

Intestinal Epithelial Cell Endoplasmic Reticulum Stress and Inflammatory Bowel Disease Pathogenesis: An Update Review

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Xiaoshi Ma

2017-10-01

Full Text Available The intestinal epithelial cells serve essential roles in maintaining intestinal homeostasis, which relies on appropriate endoplasmic reticulum (ER function for proper protein folding, modification, and secretion. Exogenous or endogenous risk factors with an ability to disturb the ER function can impair the intestinal barrier function and activate inflammatory responses in the host. The last decade has witnessed considerable progress in the understanding of the functional role of ER stress and unfolded protein response (UPR in the gut homeostasis and its significant contribution to the pathogenesis of inflammatory bowel disease (IBD. Herein, we review recent evidence supporting the viewpoint that deregulation of ER stress and UPR signaling in the intestinal epithelium, including the absorptive cells, Paneth cells, goblet cells, and enteroendocrine cells, mediates the action of genetic or environmental factors driving colitis in experimental animals and IBD patients. In addition, we highlight pharmacologic application of chaperones or small molecules that enhance protein folding and modification capacity or improve the function of the ER. These molecules represent potential therapeutic strategies in the prevention or treatment of IBD through restoring ER homeostasis in intestinal epithelial cells.

Tanshinone IIA Sodium Sulfonate Attenuates LPS-Induced Intestinal Injury in Mice

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Xin-Jing Yang

2018-01-01

Full Text Available Background. Tanshinone IIA sodium sulfonate (TSS is known to possess anti-inflammatory effects and has exhibited protective effects in various inflammatory conditions; however, its role in lipopolysaccharide- (LPS- induced intestinal injury is still unknown. Objective. The present study is designed to explore the role and possible mechanism of TSS in LPS-induced intestinal injury. Methods. Male C57BL/6J mice, challenged with intraperitoneal LPS injection, were treated with or without TSS 0.5 h prior to LPS exposure. At 1, 6, and 12 h after LPS injection, mice were sacrificed, and the small intestine was excised. The intestinal tissue injury was analyzed by HE staining. Inflammatory factors (TNF-α, IL-1β, and IL-6 in the intestinal tissue were examined by ELISA and RT-PCR. In addition, expressions of autophagy markers (microtubule-associated light chain 3 (LC3 and Beclin-1 were detected by western blot and RT-PCR. A number of autophagosomes were also observed under electron microscopy. Results. TSS treatment significantly attenuated small intestinal epithelium injury induced by LPS. LPS-induced release of inflammatory mediators, including TNF-α, IL-1β, and IL-6, were markedly inhibited by TSS. Furthermore, TSS treatment could effectively upregulate LPS-induced decrease of autophagy levels, as evidenced by the increased expression of LC3 and Beclin-1, and more autophagosomes. Conclusion. The protective effect of TSS on LPS-induced small intestinal injury may be attributed to the inhibition of inflammatory factors and promotion of autophagy levels. The present study may provide novel insight into the molecular mechanisms of TSS on the treatment of intestinal injury.

Heat stress and reduced plane of nutrition decreases intestinal integrity and function in pigs.

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Pearce, S C; Mani, V; Weber, T E; Rhoads, R P; Patience, J F; Baumgard, L H; Gabler, N K

2013-11-01

Heat stress can compromise intestinal integrity and induce leaky gut in a variety of species. Therefore, the objectives of this study were to determine if heat stress (HS) directly or indirectly (via reduced feed intake) increases intestinal permeability in growing pigs. We hypothesized that an increased heat-load causes physiological alterations to the intestinal epithelium, resulting in compromised barrier integrity and altered intestinal function that contributes to the overall severity of HS-related illness. Crossbred gilts (n=48, 43±4 kg BW) were housed in constant climate controlled rooms in individual pens and exposed to 1) thermal neutral (TN) conditions (20°C, 35-50% humidity) with ad libitum intake, 2) HS conditions (35°C, 20-35% humidity) with ad libitum feed intake, or 3) pair-fed in TN conditions (PFTN) to eliminate confounding effects of dissimilar feed intake. Pigs were sacrificed at 1, 3, or 7 d of environmental exposure and jejunum samples were mounted into modified Ussing chambers for assessment of transepithelial electrical resistance (TER) and intestinal fluorescein isothiocyanate (FITC)-labeled lipopolysaccharide (LPS) permeability (expressed as apparent permeability coefficient, APP). Further, gene and protein markers of intestinal integrity and stress were assessed. Irrespective of d of HS exposure, plasma endotoxin levels increased 45% (Pwarm summer months.

Lipopolysaccharide-binding protein: localization in secretory granules of Paneth cells in the mouse small intestine

DEFF Research Database (Denmark)

Hansen, Gert H; Rasmussen, Karina; Niels-Christiansen, Lise-Lotte

2009-01-01

Lipopolysaccharide (LPS)-binding protein (LBP) is an acute-phase protein involved in the host's response to endotoxin and mainly synthesized and secreted to the blood by the liver. But in addition, LBP is also made by extrahepatic cells, including the enterocyte-like cell line Caco-2. To study...... in closer detail the synthesis and storage of LBP in the intestinal mucosal epithelium, we performed an immunolocalization of LBP in mouse small intestine. By immunofluorescence microscopy, an antibody recognizing the 58-60 kDa protein of LBP distinctly labeled a small population of cells located deep...... into the crypts. This cell population was also positive for lysozyme and alpha-defensin 4, identifying Paneth cells as the main intestinal LBP-producing cells. By immunogold electron microscopy, intense labeling was observed in the secretory granules of these cells. We conclude that Paneth cells express LBP...

Challenges and opportunities for tissue-engineering polarized epithelium.

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Paz, Ana C; Soleas, John; Poon, James C H; Trieu, Dennis; Waddell, Thomas K; McGuigan, Alison P

2014-02-01

The epithelium is one of the most important tissue types in the body and the specific organization of the epithelial cells in these tissues is important for achieving appropriate function. Since many tissues contain an epithelial component, engineering functional epithelium and understanding the factors that control epithelial maturation and organization are important for generating whole artificial organ replacements. Furthermore, disruption of the cellular organization leads to tissue malfunction and disease; therefore, engineered epithelium could provide a valuable in vitro model to study disease phenotypes. Despite the importance of epithelial tissues, a surprisingly limited amount of effort has been focused on organizing epithelial cells into artificial polarized epithelium with an appropriate structure that resembles that seen in vivo. In this review, we provide an overview of epithelial tissue organization and highlight the importance of cell polarization to achieve appropriate epithelium function. We next describe the in vitro models that exist to create polarized epithelium and summarize attempts to engineer artificial epithelium for clinical use. Finally, we highlight the opportunities that exist to translate strategies from tissue engineering other tissues to generate polarized epithelium with a functional structure.

Mucosal prevalence and interactions with the epithelium indicate commensalism of Sutterella spp.

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Kaisa Hiippala

2016-10-01

Full Text Available Sutterella species have been frequently associated with human diseases, such as autism, Down syndrome and inflammatory bowel disease (IBD, but the impact of these bacteria on health still remains unclear. Especially the interactions of Sutterella spp. with the host are largely unknown, despite of the species being highly prevalent. In this study, we addressed the interaction of three known species of Sutterella with the intestinal epithelium and examined their adhesion properties, the effect on intestinal barrier function and the pro-inflammatory capacity in vitro. We also studied the relative abundance and prevalence of the genus Sutterella and S. wadsworthensis in intestinal biopsies of healthy individuals and patients with celiac disease (CeD or IBD. Our results show that Sutterella spp. are abundant in the duodenum of healthy adults with a decreasing gradient towards the colon. No difference was detected in the prevalence of Sutterella between the pediatric IBD or CeD patients and the healthy controls. Sutterella parvirubra adhered better than the two other Sutterella spp. to differentiated Caco-2 cells and was capable of decreasing the adherence of S. wadsworthensis, which preferably bound to mucus and human extracellular matrix (ECM proteins. Furthermore, only S. wadsworthensis induced an interleukin-8 (IL-8 production in enterocytes, which could be due to different lipopolysaccharide (LPS structures between the species. However, its pro-inflammatory activity was modest as compared to non-pathogenic Escherichia coli. Sutterella spp. had no effect on the enterocyte monolayer integrity in vitro. Our findings indicate that the members of genus Sutterella are widely prevalent commensals with mild pro-inflammatory capacity in the human gastrointestinal tract and do not contribute significantly to the disrupted epithelial homeostasis associated with microbiota dysbiosis and increase of Proteobacteria. The ability of Sutterella spp. to adhere to

THE IMPACT OF THE COOKED SAUSAGE ENRICHED WITH LACTULOSE AND FOOD FIBERS ON THE MORPHOFUNCTIONAL CONDITION OF THE MUCOUS MEMBRANE OF THE LARGE INTESTINE AND MICROBIOTA (MICROBIOCENOSIS IN RATS

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Leonid S. Kudryashov

2018-01-01

Full Text Available The researches on the development of medical and medical-preventive food products for people with violation of normal intestinal microflora are presented in the article. It was found that,  the introduction into the formulation of cooked sausage food beet  fibers based on sugar beet, hydrated in a ratio 1:5, in amount 10 %  to weight of mince and lactulose, synthesized from lactose, in  amount 640 mg/kg mince retains the traditional organoleptic  properties of the product. There were carried out comparative  morphometric, histochemical and bacterioscopic studies of boiled  sausage effect without additives and sausage enriched with food  fibers and lactulose on the morphofunctional condition of the mucous membrance of the colon (MMC of rats. Was shown a significant  height  increase of epithelial surface of epithelium, an increase of frequency mitoses in the epithelium crypts of intestinal glands (from 0.6 ± 0.08 % to 1.1 ± 0.04 %, there is a tendency of increasing  content of goblet ekzokrinnye (from 21.3 ± 5.5 % to 32.4 ± 18.7  %, while the mucosal were intensively produced allopathically  mucus, which indicates the stimulation of sausage, enriched with  lactulose on the functional status of the surface epithelium and intestinal glands of the mucous membrane of the colon. Based on the studies results of the effect of food beet fibers and lactulose,  contained in the ration of rats in large and small intestine were fixed  on order greater amount of bifido- and lactobacteries in comparison  with the animals control group. Same time, it was found that in the  large intestine the number of lactobacilli were much higher in  animals receiving experimental sausage.

Helicobacter pylori as a crucial factor in intestinal metaplasia development of gastric mucosa

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Sergii Vernygorodskyi

2016-06-01

Full Text Available Helicobacter pylori (H. pylori is detected on the surface of gastric epithelium and in goblet cells, predominantly in patients with chronic atrophic gastritis and incomplete intestinal metaplasia (IM. H. pylori infection persistence leads to the formation of gastrointestinal phenotype of IM. H. pylori can be considered as an etiological factor of IM. It inhibits the expression of SOX2 in gastric epithelial cells, hence activating transcription factor CDX2 as a counterpart to MUC5AC gene inhibition and MUC2 gene induction. Thus, in metaplastic cells, programming differentiation after intestinal phenotype will develop. The role of H. pylori in the origin of intestinal metaplasia of gastric mucosa was defined in this study to elucidate the probable mechanism of cell reprogramming. The activation of CDX2, with simultaneous inactivation and decreased number of genes (e.g., SHH, SOX2, and RUNX3 responsible for gastric differentiation, was identified to cause the appearance of IM.

Radioprotection of the intestinal crypts of mice by recombinant human interleukin-1 alpha

International Nuclear Information System (INIS)

Wu, S.G.; Miyamoto, T.

1990-01-01

Recombinant human interleukin-1 alpha (rHIL-1 alpha or IL-1) protected the intestinal crypt cells of mice against X-ray-induced damage. The survival of crypt cells measured in terms of their ability to form colonies of regenerating duodenal epithelium in situ was increased when IL-1 was given either before or after irradiation. The maximum degree of radioprotection was seen when the drug was given between 13 and 25 h before irradiation. The IL-1 dose producing maximum protection was about 6.3 micrograms/kg. This is the first report indicating that the cytokine IL-1 has a radioprotective effect in the intestine. The finding suggests that IL-1 may be of potential value in preventing radiation injury to the gut in the clinic

Effects of alanyl-glutamine supplementation on the small intestinal mucosa barrier in weaned piglets

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Shen Xing

2017-02-01

Full Text Available Objective The study was to investigate the effects of alanyl-glutamine (Ala-Gln and glutamine (Gln supplementation on the intestinal mucosa barrier in piglets. Methods A total of 180 barrows with initial weight 10.01±0.03 kg were randomly allocated to three treatments, and each treatment consisted of three pens and twenty pigs per pen. The piglets of three groups were fed with control diet [0.62% alanine (Ala], Ala-Gln diet (0.5% Ala-Gln, Gln diet (0.34% Gln and 0.21% Ala, respectively. Results The results showed that in comparison with control diet, dietary Ala-Gln supplementation increased the height of villi in duodenum and jejunum (p<0.05, Gln supplementation increased the villi height of jejunum (p<0.05, Ala-Gln supplementation up-regulated the mRNA expressions of epidermal growth factor receptor and insulin-like growth factor 1 receptor in jejunal mucosa (p<0.05, raised the mRNA expressions of Claudin-1, Occludin, zonula occludens protein-1 (ZO-1 and the protein levels of Occludin, ZO-1 in jejunal mucosa (p<0.05, Ala-Gln supplementation enlarged the number of goblet cells in duodenal and ileal epithelium (p<0.05, Gln increased the number of goblet cells in duodenal epithelium (p<0.05 and Ala-Gln supplementation improved the concentrations of secretory immunoglobulin A and immunoglobulin G in the jejunal mucosa (p<0.05. Conclusion These results demonstrated that dietary Ala-Gln supplementation could maintain the integrity of small intestine and promote the functions of intestinal mucosa barriers in piglets.

Extra-Renal Elimination of Uric Acid via Intestinal Efflux Transporter BCRP/ABCG2

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Hosomi, Atsushi; Nakanishi, Takeo; Fujita, Takuya; Tamai, Ikumi

2012-01-01

Urinary excretion accounts for two-thirds of total elimination of uric acid and the remainder is excreted in feces. However, the mechanism of extra-renal elimination is poorly understood. In the present study, we aimed to clarify the mechanism and the extent of elimination of uric acid through liver and intestine using oxonate-treated rats and Caco-2 cells as a model of human intestinal epithelium. In oxonate-treated rats, significant amounts of externally administered and endogenous uric acid were recovered in the intestinal lumen, while biliary excretion was minimal. Accordingly, direct intestinal secretion was thought to be a substantial contributor to extra-renal elimination of uric acid. Since human efflux transporter BCRP/ABCG2 accepts uric acid as a substrate and genetic polymorphism causing a decrease of BCRP activity is known to be associated with hyperuricemia and gout, the contribution of rBcrp to intestinal secretion was examined. rBcrp was confirmed to transport uric acid in a membrane vesicle study, and intestinal regional differences of expression of rBcrp mRNA were well correlated with uric acid secretory activity into the intestinal lumen. Bcrp1 knockout mice exhibited significantly decreased intestinal secretion and an increased plasma concentration of uric acid. Furthermore, a Bcrp inhibitor, elacridar, caused a decrease of intestinal secretion of uric acid. In Caco-2 cells, uric acid showed a polarized flux from the basolateral to apical side, and this flux was almost abolished in the presence of elacridar. These results demonstrate that BCRP contributes at least in part to the intestinal excretion of uric acid as extra-renal elimination pathway in humans and rats. PMID:22348008

Effect of Glucagon-like Peptide 2 on Tight Junction in Jejunal Epithelium of Weaned Pigs though MAPK Signaling Pathway

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Changsong Yu

2014-05-01

Full Text Available The glucagon-like peptide 2 (GLP-2 that is expressed in intestine epithelial cells of mammals, is important for intestinal barrier function and regulation of tight junction (TJ proteins. However, there is little known about the intracellular mechanisms of GLP-2 in the regulation of TJ proteins in piglets’ intestinal epithelial cells. The purpose of this study is to test the hypothesis that GLP-2 regulates the expressions of TJ proteins in the mitogen-activated protein kinase (MAPK signaling pathway in piglets’ intestinal epithelial cells. The jejunal tissues were cultured in a Dulbecco’s modified Eagle’s medium/high glucose medium containing supplemental 0 to 100 nmol/L GLP-2. At 72 h after the treatment with the appropriate concentrations of GLP-2, the mRNA and protein expressions of zonula occludens-1 (ZO-1, occludin and claudin-1 were increased (p<0.05. U0126, an MAPK kinase inhibitor, prevented the mRNA and protein expressions of ZO-1, occludin, claudin-1 increase induced by GLP-2 (p<0.05. In conclusion, these results indicated that GLP-2 could improve the expression of TJ proteins in weaned pigs’ jejunal epithelium, and the underlying mechanism may due to the MAPK signaling pathway.

Reinstatement of "germinal epithelium" of the ovary

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Nishida Naoyo

2006-08-01

Full Text Available Abstract Background The existing dogma that the former term ovarian "germinal epithelium" resulted from a mistaken belief that it could give rise to new germ cells is now strongly challenged. Discussion Two years ago, a research group of the University of Tennessee led by Antonin Bukovsky successfully demonstrated the oogenic process from the human ovarian covering epithelium now commonly called the ovarian surface epithelium. They showed the new oocyte with zona pellucida and granulosa cells, both originated from the surface epithelium arising from mesenchymal cells in the tunica albuginea, and stressed that the human ovary could form primary follicles throughout the reproductive period. This gives a big impact not only to the field of reproductive medicine, but also to the oncologic area. The surface epithelium is regarded as the major source of ovarian cancers, and most of the neoplasms exhibit the histology resembling müllerian epithelia. Since the differentiating capability of the surface epithelium has now expanded, the histologic range of the neoplasms in this category may extend to include both germ cell tumors and sex cord-stromal cell tumors. Summary Since the oogenic capability of ovarian surface cells has been proven, it is now believed that the oocytes can originate from them. The term "germinal epithelium", hence, might reasonably be reinstated.

Adrenergic factors regulating cell division in the colonic crypt epithelium during carcinogenesis and in colonic adenoma and adenocarcinoma.

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Kennedy, M F; Tutton, P J; Barkla, D H

1985-09-01

Evidence exists implicating adrenergic factors in the control of intestinal epithelial cell proliferation in both normal and diseased states. In this report, attention is focussed on changes in the amine requirements of proliferating cells during the chemical induction of tumours in the colon of mouse. Cell proliferation rates were measured stathmokinetically. Tumours were induced by s.c. injection of dimethylhydrazine (DMH). Results with a series of adrenoceptor agonists and antagonists suggest that there is an alpha 2-adrenoceptor mediated excitatory effect in normal colon but an alpha 2 adrenoceptor mediated inhibitory effect in adenoma and carcinoma. Alpha 1 adrenoceptors, on the other hand, have an inhibitory effect in normal crypts and in adenomas, and an excitatory effect in carcinomas. Beta adrenoceptors have an inhibitory effect in the normal and DMH-treated crypt, and in adenomas, but not in carcinomas. In the crypt epithelium of DMH-treated mice, two regions on cell proliferation, with differing regulatory factors, could be identified. In the upper region of the carcinogen-exposed crypt is a zone where cell proliferation is stimulated by an alpha 2 adrenergic mechanism, thus resembling the basal region of the normal crypt. By contrast, in the basal region of these crypts, cell proliferation is stimulated by an alpha 1 mechanism, thus resembling a malignant tumour.

Intrauterine Growth Restriction Alters Mouse Intestinal Architecture during Development.

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Fung, Camille M; White, Jessica R; Brown, Ashley S; Gong, Huiyu; Weitkamp, Jörn-Hendrik; Frey, Mark R; McElroy, Steven J

2016-01-01

Infants with intrauterine growth restriction (IUGR) are at increased risk for neonatal and lifelong morbidities affecting multiple organ systems including the intestinal tract. The underlying mechanisms for the risk to the intestine remain poorly understood. In this study, we tested the hypothesis that IUGR affects the development of goblet and Paneth cell lineages, thus compromising the innate immunity and barrier functions of the epithelium. Using a mouse model of maternal thromboxane A2-analog infusion to elicit maternal hypertension and resultant IUGR, we tested whether IUGR alters ileal maturation and specifically disrupts mucus-producing goblet and antimicrobial-secreting Paneth cell development. We measured body weights, ileal weights and ileal lengths from birth to postnatal day (P) 56. We also determined the abundance of goblet and Paneth cells and their mRNA products, localization of cellular tight junctions, cell proliferation, and apoptosis to interrogate cellular homeostasis. Comparison of the murine findings with human IUGR ileum allowed us to verify observed changes in the mouse were relevant to clinical IUGR. At P14 IUGR mice had decreased ileal lengths, fewer goblet and Paneth cells, reductions in Paneth cell specific mRNAs, and decreased cell proliferation. These findings positively correlated with severity of IUGR. Furthermore, the decrease in murine Paneth cells was also seen in human IUGR ileum. IUGR disrupts the normal trajectory of ileal development, particularly affecting the composition and secretory products of the epithelial surface of the intestine. We speculate that this abnormal intestinal development may constitute an inherent "first hit", rendering IUGR intestine susceptible to further injury, infection, or inflammation.

Regulation of intestinal homeostasis by innate immune cells.

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Kayama, Hisako; Nishimura, Junichi; Takeda, Kiyoshi

2013-12-01

The intestinal immune system has an ability to distinguish between the microbiota and pathogenic bacteria, and then activate pro-inflammatory pathways against pathogens for host defense while remaining unresponsive to the microbiota and dietary antigens. In the intestine, abnormal activation of innate immunity causes development of several inflammatory disorders such as inflammatory bowel diseases (IBD). Thus, activity of innate immunity is finely regulated in the intestine. To date, multiple innate immune cells have been shown to maintain gut homeostasis by preventing inadequate adaptive immune responses in the murine intestine. Additionally, several innate immune subsets, which promote Th1 and Th17 responses and are implicated in the pathogenesis of IBD, have recently been identified in the human intestinal mucosa. The demonstration of both murine and human intestinal innate immune subsets contributing to regulation of adaptive immunity emphasizes the conserved innate immune functions across species and might promote development of the intestinal innate immunity-based clinical therapy.

Epithelial Cell Inflammasomes in Intestinal Immunity and Inflammation

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Andrea C. Lei-Leston

2017-09-01

Full Text Available Pattern recognition receptors (PRR, such as NOD-like receptors (NLRs, sense conserved microbial signatures, and host danger signals leading to the coordination of appropriate immune responses. Upon activation, a subset of NLR initiate the assembly of a multimeric protein complex known as the inflammasome, which processes pro-inflammatory cytokines and mediates a specialized form of cell death known as pyroptosis. The identification of inflammasome-associated genes as inflammatory bowel disease susceptibility genes implicates a role for the inflammasome in intestinal inflammation. Despite the fact that the functional importance of inflammasomes within immune cells has been well established, the contribution of inflammasome expression in non-hematopoietic cells remains comparatively understudied. Given that intestinal epithelial cells (IEC act as a barrier between the host and the intestinal microbiota, inflammasome expression by these cells is likely important for intestinal immune homeostasis. Accumulating evidence suggests that the inflammasome plays a key role in shaping epithelial responses at the host–lumen interface with many inflammasome components highly expressed by IEC. Recent studies have exposed functional roles of IEC inflammasomes in mucosal immune defense, inflammation, and tumorigenesis. In this review, we present the main features of the predominant inflammasomes and their effector mechanisms contributing to intestinal homeostasis and inflammation. We also discuss existing controversies in the field and open questions related to their implications in disease. A comprehensive understanding of the molecular basis of intestinal inflammasome signaling could hold therapeutic potential for clinical translation.

Ontogenic timing mechanism initiates the expression of rat intestinal sucrase activity

International Nuclear Information System (INIS)

Yeh, K.Y.; Holt, P.R.

1986-01-01

Morphologic and enzymic differentiation occurs in rat small intestinal epithelium during 16-20 days of postnatal life. This change is considered to be initiated by an ontogenic timing mechanism and is modulated by extrinsic systemic and luminal factors. The importance of the ontogenic timing was tested directly using a transplantation technique in which jejunal isografts from newborn (day 0) and 5-day-old (day 5) rats were implanted under the skin of newborn (day 0) hosts. Isografts showing cryptvillus architecture were obtained in 44% and 21% of transplants, respectively. Day 0 isografts and host intestine expressed sucrase activity at about 16-18 days of age and showed similar crypt cell labeling and epithelial migration after [3H]thymidine injection. Day 5 isografts expressed sucrase activity when the hosts were 13 days of age, whereas host intestine showed no detectable sucrase activity. Isograft lactase activities in both experimental transplant models were significantly higher than host intestinal lactase up to 28 days of age, suggesting that luminal factors are important in modulating lactase activity during the first 4 wk of postnatal life. It is concluded that (a) no systemic factors at day 13 inhibit the expression of sucrase activity and (b) an ontogenic timing mechanism in the jejunum initiates the expression of sucrase activity

Segmental reversal of distal small intestine in short bowel syndrome

DEFF Research Database (Denmark)

Grave, Pernille Kock; Thomsen, Sabrina Valentin; Clark, Pia Susanne

2018-01-01

were the influence on cell proliferation and mucosal architecture shown by histological analysis. Methods: Sixteen piglets underwent a 60% resection of the distal small intestine and were randomized into two groups. Group 1 short bowel syndrome alone (SBS) (n = 8) and group 2 with reversal of a distal...... small intestinal segment (SBS-RS) (n = 8). Body weight was measured daily and the pigs were euthanized after 1 month. Crypt depths, villus heights and muscle layers thicknesses were measured. For the evaluation of microvilli of the brush border of the epithelium and cell proliferation...... was found in the SBS group and increase in the thickness of the circular and longitudinal muscle layers in the SBS-RS group. In the distal ileal segment the longitudinal muscle layer thicknesses were increased in the SBS group. Otherwise, no significant changes were found. Conclusion: Reversal of a 20-cm...

Effect of Psychoneural Factors on Intestinal Epithelial Function

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M Cecilia Berin

1997-01-01

Full Text Available Stress has been associated with abnormal gastrointestinal function, including diarrhea and abdominal pain, and stress-associated gastric ulceration has frequently been documented. Stress can also exacerbate ongoing pathophysiology and often precedes relapses in patients with inflammatory bowel disease or irritable bowel syndrome. The relatively new field of psychoneuroimmunology is involved with the elucidation of mechanisms that explain the link between the central nervous system and immune-mediated pathophysiology. Recent progress examining the interaction among the nervous system, the immune system and the epithelium of the intestine is discussed, and the evidence for central nervous sysytem control of this interaction is examined.

Mucosal pathobiology and molecular signature of epithelial barrier dysfunction in the small intestine in irritable bowel syndrome.

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González-Castro, Ana M; Martínez, Cristina; Salvo-Romero, Eloísa; Fortea, Marina; Pardo-Camacho, Cristina; Pérez-Berezo, Teresa; Alonso-Cotoner, Carmen; Santos, Javier; Vicario, María

2017-01-01

Irritable bowel syndrome (IBS) is one of the most prevalent gastrointestinal disorders in developed countries. Its etiology remains unknown; however, a common finding, regardless of IBS subtype, is the presence of altered intestinal barrier. In fact, signaling and location of cell-to-cell adhesion proteins, in connection with increased immune activity, seem abnormal in the intestinal epithelium of IBS patients. Despite that most research is performed on distal segments of the intestine, altered permeability has been reported in both, the small and the large bowel of all IBS subtypes. The small intestine carries out digestion and nutrient absorption and is also the site where the majority of immune responses to luminal antigens takes place. In fact, the upper intestine is more exposed to environmental antigens than the colon and is also a site of symptom generation. Recent studies have revealed small intestinal structural alterations of the epithelial barrier and mucosal immune activation in association with intestinal dysfunction, suggesting the commitment of the intestine as a whole in the pathogenesis of IBS. This review summarizes the most recent findings on mucosal barrier alterations and its relationship to symptoms arising from the small intestine in IBS, including epithelial structural abnormalities, mucosal immune activation, and microbial dysbiosis, further supporting the hypothesis of an organic origin of IBS. © 2016 Journal of Gastroenterology and Hepatology Foundation and John Wiley & Sons Australia, Ltd.

Cytokeratin expression in mouse lacrimal gland germ epithelium.

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Hirayama, Masatoshi; Liu, Ying; Kawakita, Tetsuya; Shimmura, Shigeto; Tsubota, Kazuo

2016-05-01

The lacrimal gland secretes tear fluids that protect the ocular surface epithelium, and its dysfunction leads to dry eye disease (DED). The functional restoration of the lacrimal gland by engraftment of a bioengineered lacrimal gland using lacrimal gland germ epithelial cells has been proposed to cure DED in mice. Here, we investigate the expression profile of cytokeratins in the lacrimal gland germ epithelium to clarify their unique characteristics. We performed quantitative polymerase chain reaction (Q-PCR) and immunohistochemistry (IHC) analysis to clarify the expression profile of cytokeratin in the lacrimal gland germ epithelium. The mRNA expression of keratin (KRT) 5, KRT8, KRT14, KRT15, and KRT18 in the lacrimal gland germ epithelium was increased compared with that in mouse embryonic stem cells and the lacrimal gland germ mesenchyme, as analyzed by Q-PCR. The expression level of KRT15 increased in the transition from stem cells to lacrimal gland germ epithelium, then decreased as the lacrimal gland matured. IHC revealed that the expression set of these cytokeratins in the lacrimal gland germ epithelium was different from that in the adult lacrimal gland. The expression of KRT15 was observed in the lacrimal gland germ epithelium, and it segmentalized into some of the basal cells in the intercanulated duct in mature gland. We determined the expression profile of cytokeratins in the lacrimal gland epithelium, and identified KRT15 as a candidate unique cellular marker for the lacrimal gland germ epithelium. Copyright © 2015 Elsevier Ltd. All rights reserved.

Mathematical modelling of the death rate dynamics in mammals with intestinal form of radiation sicleness

International Nuclear Information System (INIS)

Smirnova, O.A.

1990-01-01

A mathematical models has been developed to describe the death rate dynamics in irradiated mammals. The model links statistical biometric functions with statistical and dynamic characteristics of the organism's 'critical' system. There is an agreement between the results of modelling and experiments with respect to death rate dynamics of small laboratory animals subjected to acute and chronic irradiation with doses and dose-rates at which small intestine epithelium is 'ctitical'

Toxic death of mouse small intestinal enterocytes as a function of intervals between injections of the S-phase-specific agent hydroxyurea

International Nuclear Information System (INIS)

Churikova, L.I.; Krinskaya, A.V.; Dibrov, B.F.; Zhabotinskii, A.M.; Neifakh, Yu.A.; Gel'fand, E.V.

1986-01-01

The authors study optimal conditions for administration of hydroxyurea to mice to ensure minimal damage to intestinal enterocytes. Before receiving an injection of hydroxyurea the mice were irradiated in a dose of 200 rads from a 137 Cs source to activate proliferation of the epithelial cells. The morphometric parameters of the epithelium after injection of hydroxyurea are given. A resonance increase in the survival rate of the enterocytes was revealed if the cytostatic was injected with a period close to the average duration of the cell cycle of the regenerating intestinal cells

Demonstration of Brachyspira aalborgi lineages 2 and 3 in human colonic biopsies with intestinal spirochaetosis by specific fluorescent in situ hybridization

DEFF Research Database (Denmark)

Jensen, Tim Kåre; Teglbjærg, Peter S.; Lindboe, Christian F.

2004-01-01

of these organisms in human intestinal spirochaetosis. Seventeen human colonic biopsies from Norway and Denmark with intestinal spirochaetosis caused by Brachyspira-like organisms different from the type strain of B. aalborgi (lineage 1) were examined. Application of the probe gave a positive signal in two Norwegian...... biopsies, whereas the 15 other biopsies were hybridization-negative. The positive reaction visualized the spirochaetes as a fluorescent, 3-5 mum-high fringe on the surface epithelium, extending into the crypts. The study verified the presence of B. aalborgi lineages 2 and 3 and identified the bacteria...

Expression of cyclooxygenase-2 in intestine of pigs of different ages and hygiene status

DEFF Research Database (Denmark)

Lauridsen, Charlotte; Whiting, C; Lewis, M

2010-01-01

treatments: One group of piglets suckled the sow, a second group was put into an isolator and fed a milk formula, and a third group was put into the isolator fed milk formula and injected with broad spectrum antibiotics. Samples were collected from the 75% level of the small intestine at day 5, 28 and 56...... of age. Tissue section from four piglets from each of these six treatment groups was analysed by immunofluorescence for COX-2 and type-IV collagen (basement membrane, defining lamina propria (LP)). Image analysis was used to determine the number of positive pixels expressing LP and epithelial COX-2. COX......-2 expressing cells were observed in LP and epithelium in all porcine intestinal samples. When analysing images obtained on day 28, injection of antibiotics seemed to reduce the COX-2 expression in intestinal samples of piglets when compared to other treatments (P = 0.053). No significant effect...

Genome-wide RNAi Screen Identifies Networks Involved in Intestinal Stem Cell Regulation in Drosophila

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Xiankun Zeng

2015-02-01

Full Text Available The intestinal epithelium is the most rapidly self-renewing tissue in adult animals and maintained by intestinal stem cells (ISCs in both Drosophila and mammals. To comprehensively identify genes and pathways that regulate ISC fates, we performed a genome-wide transgenic RNAi screen in adult Drosophila intestine and identified 405 genes that regulate ISC maintenance and lineage-specific differentiation. By integrating these genes into publicly available interaction databases, we further developed functional networks that regulate ISC self-renewal, ISC proliferation, ISC maintenance of diploid status, ISC survival, ISC-to-enterocyte (EC lineage differentiation, and ISC-to-enteroendocrine (EE lineage differentiation. By comparing regulators among ISCs, female germline stem cells, and neural stem cells, we found that factors related to basic stem cell cellular processes are commonly required in all stem cells, and stem-cell-specific, niche-related signals are required only in the unique stem cell type. Our findings provide valuable insights into stem cell maintenance and lineage-specific differentiation.

Nitric oxide (NO) production in mammalian non-tumorigenic epithelial cells of the small intestine and macrophages induced by individual strains of lactobacilli and bifidobacteria

DEFF Research Database (Denmark)

Pipenbaher, Natasa; Møller, Peter Lange; Dolinsek, Jan

2009-01-01

and absence of interferon gamma (INF-¿). Production of NO in intestinal epithelium was stimulated by individual strains of lactobacilli without INF-¿ priming. While none of the tested bifidobacteria were capable of inducing NO production, most constitutively secreted NO. Most tested strains induced...

Claudin-3 expression in radiation-exposed rat models: A potential marker for radiation-induced intestinal barrier failure

Energy Technology Data Exchange (ETDEWEB)

Shim, Sehwan; Lee, Jong-geol; Bae, Chang-hwan; Lee, Seung Bum [National Radiation Emergency Medical Center, Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of); Jang, Won-Suk; Lee, Sun-Joo [Laboratory of Experimental Pathology, Korea Cancer Center Hospital, Seoul (Korea, Republic of); Lee, Seung-Sook [National Radiation Emergency Medical Center, Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of); Department of Pathology, Korea Cancer Center Hospital, Seoul (Korea, Republic of); Park, Sunhoo, E-mail: sunhoo@kcch.re.kr [National Radiation Emergency Medical Center, Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of); Department of Pathology, Korea Cancer Center Hospital, Seoul (Korea, Republic of)

2015-01-02

Highlights: • Irradiation increased intestinal bacterial translocation, accompanied by claudin protein expression in rats. • Neurotensin decreased the bacterial translocation and restored claudin-3 expression. • Claudin-3 can be used as a marker in evaluating radiation induced intestinal injury. - Abstract: The molecular events leading to radiation-induced intestinal barrier failure are not well known. The influence of the expression of claudin proteins in the presence and absence of neurotensin was investigated in radiation-exposed rat intestinal epithelium. Wistar rats were randomly divided into control, irradiation, and irradiation + neurotensin groups, and bacterial translocation to the mesenteric lymph node and expression of claudins were determined. Irradiation led to intestinal barrier failure as demonstrated by significant bacterial translocation. In irradiated terminal ilea, expression of claudin-3 and claudin-4 was significantly decreased, and claudin-2 expression was increased. Administration of neurotensin significantly reduced bacterial translocation and restored the structure of the villi as seen by histologic examination. Among the three subtype of claudins, only claudin-3 expression was restored. These results suggest that the therapeutic effect of neurotensin on the disruption of the intestinal barrier is associated with claudin-3 alteration and that claudin-3 could be used as a marker in evaluating radiation-induced intestinal injury.

Bidirectional Signaling of Mammary Epithelium and Stroma: Implications for Breast Cancer—Preventive Actions of Dietary Factors

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The mammary gland is composed of two major cellular compartments: a highly dynamic epithelium that undergoes cycles of proliferation, differentiation, and apoptosis in response to local and endocrine signals and the underlying stroma comprised of fibroblasts, endothelial cells, and adipocytes that c...

Autoradiographic study of the permeability characteristics of the small intestine

Energy Technology Data Exchange (ETDEWEB)

Kingham, J G.C.; Baker, J H; Loehry, C A [Royal Victoria Hospital, Bournemouth (UK)

1978-02-01

This autoradiographic study demonstrates the distribution of a range of small solutes and macromolecules in the mucosa of the guinea-pig small intestine after intracardiac injection. The substances investigated were: /sup 14/C-urea, /sup 3/H-mannose, /sup 3/H-inulin, and /sup 125/I polyvinylpyrrolidone (PVP). Small bowel biopsies were taken at intervals from one to 60 minutes after injection and the tissues processed for autoradiography. Light microscopic examination of the autoradiographs showed that the compartmental distribution depended on the molecular size of the substances being studied. Urea and mannose, as small solutes, were uniformly distributed throughout the intravascular, extravascular, and epithelial compartments. Inulin was evenly distributed in the vessel lumen and extravascular space but there was a considerable drop in concentration in the epithelium. PVP exhibited the most marked gradients, the concentration being greatest in the vascular lumina, lower in the extravascular space, least in the epithelium. Thus there appear to be two barriers to macromolecular passage which are freely permeable to small solutes: the capillary wall and the epithelium. At a light microscopical level it was not possible to observe whether the limiting membrane of each of these barriers is the cell plasmalemmal membrane or the basement membrane. The selectivity of the epithelial barrier was greater than that of the capillary barrier.

Non-equivalence of Wnt and R-spondin ligands during Lgr5+ intestinal stem-cell self-renewal.

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Yan, Kelley S; Janda, Claudia Y; Chang, Junlei; Zheng, Grace X Y; Larkin, Kathryn A; Luca, Vincent C; Chia, Luis A; Mah, Amanda T; Han, Arnold; Terry, Jessica M; Ootani, Akifumi; Roelf, Kelly; Lee, Mark; Yuan, Jenny; Li, Xiao; Bolen, Christopher R; Wilhelmy, Julie; Davies, Paige S; Ueno, Hiroo; von Furstenberg, Richard J; Belgrader, Phillip; Ziraldo, Solongo B; Ordonez, Heather; Henning, Susan J; Wong, Melissa H; Snyder, Michael P; Weissman, Irving L; Hsueh, Aaron J; Mikkelsen, Tarjei S; Garcia, K Christopher; Kuo, Calvin J

2017-05-11

The canonical Wnt/β-catenin signalling pathway governs diverse developmental, homeostatic and pathological processes. Palmitoylated Wnt ligands engage cell-surface frizzled (FZD) receptors and LRP5 and LRP6 co-receptors, enabling β-catenin nuclear translocation and TCF/LEF-dependent gene transactivation. Mutations in Wnt downstream signalling components have revealed diverse functions thought to be carried out by Wnt ligands themselves. However, redundancy between the 19 mammalian Wnt proteins and 10 FZD receptors and Wnt hydrophobicity have made it difficult to attribute these functions directly to Wnt ligands. For example, individual mutations in Wnt ligands have not revealed homeostatic phenotypes in the intestinal epithelium-an archetypal canonical, Wnt pathway-dependent, rapidly self-renewing tissue, the regeneration of which is fueled by proliferative crypt Lgr5 + intestinal stem cells (ISCs). R-spondin ligands (RSPO1-RSPO4) engage distinct LGR4-LGR6, RNF43 and ZNRF3 receptor classes, markedly potentiate canonical Wnt/β-catenin signalling, and induce intestinal organoid growth in vitro and Lgr5 + ISCs in vivo. However, the interchangeability, functional cooperation and relative contributions of Wnt versus RSPO ligands to in vivo canonical Wnt signalling and ISC biology remain unknown. Here we identify the functional roles of Wnt and RSPO ligands in the intestinal crypt stem-cell niche. We show that the default fate of Lgr5 + ISCs is to differentiate, unless both RSPO and Wnt ligands are present. However, gain-of-function studies using RSPO ligands and a new non-lipidated Wnt analogue reveal that these ligands have qualitatively distinct, non-interchangeable roles in ISCs. Wnt proteins are unable to induce Lgr5 + ISC self-renewal, but instead confer a basal competency by maintaining RSPO receptor expression that enables RSPO ligands to actively drive and specify the extent of stem-cell expansion. This functionally non-equivalent yet cooperative interaction

Comparative studies on intestine ultrastructure of third-stage larvae and adults of Cystidicoloides ephemeridarum (Nematoda, Cystidicolidae).

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Frantová, Denisa; Moravec, Frantisek

2004-11-01

The intestinal epithelium of third-stage larvae and adults of Cystidicoloides ephemeridarum from haemocoel of mayflies and stomach of brown trout was studied by electron microscopy and cytochemistry. In section, the intestine of both stages is composed of a single layer of about ten undifferentiated intestinal cells in a ring. A labyrinth of deep invaginations is present in the basal region of each cell. The apical surface is modified into well developed, regularly arranged microvilli. These, together with numerous organelles engaged in metabolism and a well defined gut lumen filled with unidentifiable material suggest that the intestine may function in digestion and absorption during both stages. The adults seem to feed upon the semifluid content of the stomach of brown trout. Fortuitous oral infection with undetermined bacteria in vitro led to degenerative changes in the intestinal tissue and probably caused death of the infected specimens. Up to 75% of the cell volume in the L(3) is occupied by glycogen deposits. In the adults, a minor portion of glycogen, together with lipid droplets, has been observed. The adults are considered to rely more on aerobic metabolism, whereas anaerobic metabolism (glycolysis) may prevail in L(3).

Role of serotonin in the intestinal mucosal epithelium barrier in weaning mice undergoing stress-induced diarrhea.

Science.gov (United States)

Dong, Yulan; Wang, Zixu; Qin, Zhuoming; Cao, Jing; Chen, Yaoxing

2018-02-01

Stress-induced diarrhea is a frequent and challenging threat to humans and domestic animals. Serotonin (5-HT) has been shown to be involved in the pathological process of stress-induced diarrhea. However, the role of 5-HT in stress-induced diarrhea remains unclear. A stress-induced diarrhea model was established in 21-day-old ICR weaning mice through an intragastric administration of 0.25 mL of 0.4 g/mL folium sennae and restraint of the hind legs with adhesive tape for 4 h to determine whether 5-HT regulates the mucosal barrier to cause diarrhea. Mice with decreased levels of 5-HT were pretreated with an intraperitoneal injection of 300 mg/kg p-chlorophenylalanine (PCPA), a 5-HT synthesis inhibitor. After 5 days of treatment, the stress level, body weight and intestinal mucosal morphology indexes were measured. Compared to the controls, the mice with stress-induced diarrhea displayed a stress reaction, with increased corticosterone levels, as well as increased 5-HT-positive cells. However, the mice with stress-induced diarrhea exhibited decreased body weights, villus height to crypt depth ratios (V/C), and Occludin and Claudin1 expression. The PCPA injection reversed these effects in mice with different degrees of stress-induced diarrhea. Based on these findings, inhibition of 5-HT synthesis relieved the stress response and improved the health of the intestinal tract, including both the intestinal absorption capacity, as determined by the villus height and crypt depth, and the mucosal barrier function, as determined by the tight junction proteins of epithelial cell.

Rupture, Invasion and Inflammatory Destruction of the Intestinal Barrier by Shigella: The Yin and Yang of Innate Immunity

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Philippe J Sansonetti

2006-01-01

Full Text Available Shigella is a Gram-negative bacterial species of the family Enterobacteriaceae that causes bacillary dysentery in humans. This acute colitis reflects the capacity of the microorganism to disrupt, invade and cause the inflammatory destruction of the intestinal epithelium. The pathogenesis of the Shigella infection can be seen as a disruption of the homeostatic balance that protects the gut against inflammation in the presence of its commensal flora. This provides the unified view that enteroinvasive pathogens allow for the identification of key signalling molecules and pathways involved in the regulation of intestinal inflammation, and more generally, in the regulation of the innate and adaptive immune response.

Intestinal Stem Cell Markers in the Intestinal Metaplasia of Stomach and Barrett's Esophagus.

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Bo Gun Jang

Full Text Available Gastric intestinal metaplasia (IM is a highly prevalent preneoplastic lesion; however, the molecular mechanisms regulating its development remain unclear. We have previously shown that a population of cells expressing the intestinal stem cell (ISC marker LGR5 increases remarkably in IM. In this study, we further investigated the molecular characteristics of these LGR5+ cells in IM by examining the expression profile of several ISC markers. Notably, we found that ISC markers-including OLFM4 and EPHB2-are positively associated with the CDX2 expression in non-tumorous gastric tissues. This finding was confirmed in stomach lesions with or without metaplasia, which demonstrated that OLFM4 and EPHB2 expression gradually increased with metaplastic progression. Moreover, RNA in situ hybridization revealed that LGR5+ cells coexpress several ISC markers and remained confined to the base of metaplastic glands, reminiscent to that of normal intestinal crypts, whereas those in normal antral glands expressed none of these markers. Furthermore, a large number of ISC marker-expressing cells were diffusely distributed in gastric adenomas, suggesting that these markers may facilitate gastric tumorigenesis. In addition, Barrett's esophagus (BE-which is histologically similar to intestinal metaplasia-exhibited a similar distribution of ISC markers, indicating the presence of a stem cell population with intestinal differentiation potential. In conclusion, we identified that LGR5+ cells in gastric IM and BE coexpress ISC markers, and exhibit the same expression profile as those found in normal intestinal crypts. Taken together, these results implicate an intestinal-like stem cell population in the pathogenesis of IM, and provide an important basis for understanding the development and maintenance of this disease.

Regulation of intestinal immune responses through TLR activation: implications for pro- and prebiotics

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Sander eDe Kivit

2014-02-01

Full Text Available The intestinal mucosa is constantly facing a high load of antigens including bacterial antigens derived from the microbiota and food. Despite this, the immune cells present in the gastrointestinal tract do not initiate a pro-inflammatory immune response. Toll-like receptors (TLRs are pattern recognition receptors expressed by various cells in the gastrointestinal tract, including intestinal epithelial cells (IEC and resident immune cells in the lamina propria. Many diseases, including chronic intestinal inflammation (e.g. inflammatory bowel disease, irritable bowel syndrome (IBS, allergic gastroenteritis (e.g. eosinophilic gastroenteritis and allergic IBS and infections are nowadays associated with a deregulated microbiota. The microbiota may directly interact with TLR. In addition, differences in intestinal TLR expression in health and disease may suggest that TLR play an essential role in disease pathogenesis and may be novel targets for therapy. TLR signaling in the gut is involved in either maintaining intestinal homeostasis or the induction of an inflammatory response. This mini review provides an overview of the current knowledge regarding the contribution of intestinal epithelial TLR signaling in both tolerance induction or promoting intestinal inflammation, with a focus on food allergy. We will also highlight a potential role of the microbiota in regulating gut immune responses, especially through TLR activation.

Urokinase and the intestinal mucosa: evidence for a role in epithelial cell turnover

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Gibson, P; Birchall, I; Rosella, O; Albert, V; Finch, C; Barkla, D; Young, G

1998-01-01

Background—The functions of urokinase in intestinal epithelia are unknown. 
Aims—To determine the relation of urokinase expressed by intestinal epithelial cells to their position in the crypt-villus/surface axis and of mucosal urokinase activity to epithelial proliferative kinetics in the distal colon. 
Methods—Urokinase expression was examined immunohistochemically in human intestinal mucosa. Urokinase activity was measured colorimetrically in epithelial cells isolated sequentially from the crypt-villus axis of the rat small intestine. In separate experiments, urokinase activity and epithelial kinetics (measured stathmokinetically) were measured in homogenates of distal colonic mucosa of 14 groups of eight rats fed diets known to alter epithelial turnover. 
Results—From the crypt base, an ascending gradient of expression and activity of urokinase was associated with the epithelial cells. Median mucosal urokinase activities in each of the dietary groups of rats correlated positively with autologous median number of metaphase arrests per crypt (r=0.68; p<0.005) and per 100 crypt cells (r=0.75; p<0.001), but not with crypt column height. 
Conclusions—Localisation of an enzyme capable of leading to digestion of cell substratum in the region where cells are loosely attached to their basement membrane, and the association of its activity with indexes of cell turnover, suggest a role for urokinase in facilitating epithelial cell loss in the intestine. 

 Keywords: urokinase; intestinal epithelium; colon; epithelial proliferation PMID:9824347

Saccharomyces boulardii improves intestinal epithelial cell restitution by inhibiting αvβ5 integrin activation state.

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Alexandra Canonici

Full Text Available Intestinal epithelial cell damage is frequently seen in the mucosal lesions of infectious or inflammatory bowel diseases such as ulcerative colitis or Crohn's disease. Complete remission of these diseases requires both the disappearance of inflammation and the repair of damaged epithelium. Saccharomyces boulardii (Sb, Biocodex is a non-pathogenic yeast widely used as a preventive and therapeutic probiotic for the prevention and treatment of diarrhea and other gastrointestinal disorders. We recently showed that it enhances the repair of intestinal epithelium through activation of α2β1 integrin collagen receptors. In the present study, we demonstrated that α2β1 integrin is not the sole cell-extracellular matrix receptor involved during Sb-mediated intestinal restitution. Indeed, by using cell adhesion assays, we showed that Sb supernatant contains heat sensitive molecule(s, with a molecular weight higher than 9 kDa, which decreased αvβ5 integrin-mediated adhesion to vitronectin by competing with the integrin. Moreover, Sb-mediated changes in cell adhesion to vitronectin resulted in a reduction of the αvβ5signaling pathway. We used a monolayer wounding assay that mimics in vivo cell restitution to demonstrate that down-modulation of the αvβ5 integrin-vitronectin interaction is related to Sb-induced cell migration. We therefore postulated that Sb supernatant contains motogenic factors that enhance cell restitution through multiple pathways, including the dynamic fine regulation of αvβ5 integrin binding activity. This could be of major importance in diseases characterized by severe mucosal injury, such as inflammatory and infectious bowel diseases.

Morphological and functional alterations of small intestine in chronic pancreatitis.

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Gubergrits, Natalya B; Linevskiy, Yuri V; Lukashevich, Galina M; Fomenko, Pavel G; Moroz, Tatyana V; Mishra, Tapan

2012-09-10

The small intestine in chronic pancreatitis has not been investigated yet thoroughly. It would be important to understand fat metabolism in the course of this disease and could be explained if the small intestine has some pathological conditions and, due to this reason, pancreatic enzyme substitution does not work in all patients. To investigate the pathophysiology of small intestine in chronic pancreatitis and to show the reason why in some cases pancreatic enzyme substitution does not work properly. In the process of the study 33 chronic pancreatitis patients have been examined. The control group includes 30 subjects without chronic pancreatitis similar for age, sex and alcohol consumption to the patients with chronic pancreatitis patients. Aspiration biopsy of jejunum mucosa followed by histological examination and investigation of intestinal enzymes by aspiration has been performed. Metabolism at membranic level has been studied by enzymatic activity of amylase and lipase in the small intestine. Production of enzymes (monoglyceride lipase, lactase, saccharase, maltase, glycyl-l-leucine dipeptidase) promoting metabolism in enterocytes has been estimated as to their activity in homogenates of jejunum mucosa samples. Participation of mucosa in intestinal digestion has been assessed by alkaline phosphatase activity in a secretory chyme from proximal portion of jejunum. Absorptive capacity of jejunum was evaluated by D-xylose test results. DNA, lysozyme, immunoglobulin contents of chyme have also been calculated and bacteriological study of chyme has been also performed. Secondary enteritis, accompanied by moderate dystrophic changes of mucous membrane, thinning of limbus, and decrease of Paneth cell mitotic index, was found to occur in chronic pancreatitis patients. Enteritis is followed by changes in enzymatic processes in the sphere of membrane and intestinal digestion, decrease of absorption, accelerated desquamation of epithelium, fall in local immunity and

Expression of Toll-like receptor 9 and response to bacterial CpG oligodeoxynucleotides in human intestinal epithelium

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Pedersen, G; Andresen, Lars; Matthiessen, M W

2005-01-01

Recognition of repeat CpG motifs, which are common in bacterial, but not in mammalian, DNA, through Toll-like receptor (TLR)9 is an integral part of the innate immune system. As the role of TLR9 in the human gut is unknown, we determined the spectrum of TLR9 expression in normal and inflamed colo...... in vitro despite spontaneous TLR9 gene expression. This suggests that the human epithelium is able to avoid inappropriate immune responses to luminal bacterial products through modulation of the TLR9 pathway....

Current and emerging approaches to define intestinal epithelium-specific transcriptional networks

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Olsen, Anders Krûger; Boyd, Mette; Danielsen, Erik Thomas

2012-01-01

Upon developmental or environmental cues, the composition of transcription factors in a transcriptional regulatory network is deeply implicated in controlling the signature of the gene expression and thereby specifies the cell- or tissue-type. Novel methods including ChIP-chip and ChIP-Seq have...

Current and emerging approaches to define intestinal epithelium-specific transcriptional networks

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Olsen, Anders Krüger; Boyd, Mette; Danielsen, Erik Thomas

2012-01-01

Upon developmental or environmental cues, the composition of transcription factors in a transcriptional regulatory network is deeply implicated in controlling the signature of the gene expression and thereby specifies the cell or tissue type. Novel methods including ChIP-chip and ChIP-Seq have been...

Cyclosporine a inhibits apoptosis of rat gingival epithelium.

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Ma, Su; Liu, Peihong; Li, Yanwu; Hou, Lin; Chen, Li; Qin, Chunlin

2014-08-01

The use of cyclosporine A (CsA) induces hyperplasia of the gingival epithelium in a site-specific response manner, but the molecular mechanism via which the lesion occurs is unclear. The present research aims to investigate the site-specific effect of CsA on the apoptosis of gingival epithelium associated with gingival hyperplasia. Forty Wistar rats were divided into CsA-treated and non-treated groups. Paraffin-embedded sections of mandibular first molars were selected for hematoxylin and eosin staining, immunohistochemistry analyses of bcl-2 and caspase-3, and the staining of terminal deoxynucleotidyl transfer-mediated dUTP nick-end labeling (TUNEL). The area of the whole gingival epithelium and the length of rete pegs were measured, and the number of bcl-2- and caspase-3-positive cells in the longest rete peg were counted. The analysis of variance for factorial designs and Fisher least significant difference test for post hoc analysis were used to determine the significance levels. In CsA-treated rats, bcl-2 expression was significantly upregulated, whereas caspase-3 expression was downregulated, along with a reduced number of TUNEL-positive cells. The site-specific distribution of bcl-2 was consistent with the site-specific hyperplasia of the gingival epithelium in CsA-treated rats. CsA inhibited gingival epithelial apoptosis via the mitochondrial pathway and common pathway. The antiapoptotic protein bcl-2 might play a critical role in the pathogenesis of the site-specific hyperplasia of gingival epithelium induced by CsA. There were mechanistic differences in the regulation of apoptosis for cells in the attached gingival epithelium, free gingival epithelium, and junctional epithelium.

Humoral immunity provides resident intestinal eosinophils access to luminal antigen via eosinophil-expressed low affinity Fc gamma receptors

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Smith, Kalmia M.; Rahman, Raiann S.; Spencer, Lisa A.

2016-01-01

Eosinophils are native to the healthy gastrointestinal tract, and are associated with inflammatory diseases likely triggered by exposure to food allergens (e.g. food allergies and eosinophilic gastrointestinal disorders). In models of allergic respiratory diseases and in vitro studies, direct antigen engagement elicits eosinophil effector functions including degranulation and antigen presentation. However, it was not known whether intestinal tissue eosinophils that are separated from luminal food antigens by a columnar epithelium might similarly engage food antigens. Using an intestinal ligated loop model in mice, here we determined that resident intestinal eosinophils acquire antigen from the lumen of antigen-sensitized but not naïve mice in vivo. Antigen acquisition was immunoglobulin-dependent; intestinal eosinophils were unable to acquire antigen in sensitized immunoglobulin-deficient mice, and passive immunization with immune serum or antigen-specific IgG was sufficient to enable intestinal eosinophils in otherwise naïve mice to acquire antigen in vivo. Intestinal eosinophils expressed low affinity IgG receptors, and the activating receptor FcγRIII was necessary for immunoglobulin-mediated acquisition of antigens by isolated intestinal eosinophils in vitro. Our combined data suggest that intestinal eosinophils acquire lumen-derived food antigens in sensitized mice via FcγRIII antigen focusing, and may therefore participate in antigen-driven secondary immune responses to oral antigens. PMID:27683752

Humoral Immunity Provides Resident Intestinal Eosinophils Access to Luminal Antigen via Eosinophil-Expressed Low-Affinity Fcγ Receptors.

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Smith, Kalmia M; Rahman, Raiann S; Spencer, Lisa A

2016-11-01

Eosinophils are native to the healthy gastrointestinal tract and are associated with inflammatory diseases likely triggered by exposure to food allergens (e.g., food allergies and eosinophilic gastrointestinal disorders). In models of allergic respiratory diseases and in vitro studies, direct Ag engagement elicits eosinophil effector functions, including degranulation and Ag presentation. However, it was not known whether intestinal tissue eosinophils that are separated from luminal food Ags by a columnar epithelium might similarly engage food Ags. Using an intestinal ligated loop model in mice, in this study we determined that resident intestinal eosinophils acquire Ag from the lumen of Ag-sensitized but not naive mice in vivo. Ag acquisition was Ig-dependent; intestinal eosinophils were unable to acquire Ag in sensitized Ig-deficient mice, and passive immunization with immune serum or Ag-specific IgG was sufficient to enable intestinal eosinophils in otherwise naive mice to acquire Ag in vivo. Intestinal eosinophils expressed low-affinity IgG receptors, and the activating receptor FcγRIII was necessary for Ig-mediated acquisition of Ags by isolated intestinal eosinophils in vitro. Our combined data suggest that intestinal eosinophils acquire lumen-derived food Ags in sensitized mice via FcγRIII Ag focusing and that they may therefore participate in Ag-driven secondary immune responses to oral Ags. Copyright © 2016 by The American Association of Immunologists, Inc.

In vivo models of human airway epithelium repair and regeneration

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C. Coraux

2005-12-01

Full Text Available Despite an efficient defence system, the airway surface epithelium, in permanent contact with the external milieu, is frequently injured by inhaled pollutants, microorganisms and viruses. The response of the airway surface epithelium to an acute injury includes a succession of cellular events varying from the loss of the surface epithelium integrity to partial shedding of the epithelium or even to complete denudation of the basement membrane. The epithelium has then to repair and regenerate to restore its functions. The in vivo study of epithelial regeneration in animal models has shown that airway epithelial cells are able to dedifferentiate, spread, migrate over the denuded basement membrane and progressively redifferentiate to reconstitute a functional respiratory epithelium after several weeks. Humanised tracheal xenograft models have been developed in immunodeficient nude and severe combined immunodeficient (SCID mice in order to mimic the natural regeneration process of the human airway epithelium and to analyse the cellular and molecular events involved during the different steps of airway epithelial reconstitution. These models represent very powerful tools for analysing the modulation of the biological functions of the epithelium during its regeneration. They are also very useful for identifying stem/progenitor cells of the human airway epithelium. A better knowledge of the mechanisms involved in airway epithelium regeneration, as well as the characterisation of the epithelial stem and progenitor cells, may pave the way to regenerative therapeutics, allowing the reconstitution of a functional airway epithelium in numerous respiratory diseases, such as asthma, chronic obstructive pulmonary diseases, cystic fibrosis and bronchiolitis.

Excreted/secreted Trichuris suis products reduce barrier function and suppress inflammatory cytokine production of intestinal epithelial cells

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Hiemstra, I. H.; Klaver, E. J.; Vrijland, K.

2014-01-01

The administration of helminths is considered a promising strategy for the treatment of autoimmune diseases due to their immunomodulatory properties. Currently, the application of the helminth Trichuris suis as a treatment for Crohn's disease is being studied in large multi-center clinical trials....... The intestinal epithelium forms an efficient barrier between the intestinal lumen containing the microbial flora and helminths, and dendritic cells (DCs) present in the lamina propria that determine the TH response. Here, we investigated how excreted/secreted (E/S) products of T. suis affect the barrier function...... of intestinal epithelial cells (IECs) in order to reach the DCs and modulate the immune response. We show that T. suis E/S products reduce the barrier function and the expression of the tight junction proteins EMP-1 and claudin-4 in IEC CMT93/69 monolayers in a glycan-dependent manner. This resulted...

Effects of size of Trichostrongylus colubriformis infections on histopathology of the mucosa along the whole small intestine in rabbits.

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Hoste, H; Mallet, S

1990-11-01

The influence of population size of Trichostrongylus colubriformis on the structures of the small intestine, especially with regard to the development and origin of an intestinal adaptive response, was examined in experimentally infected rabbits. The effects of low (500 L3) and high (50,000 L3) infection on histological (villous length, mucosa to serosa ratio, crypt surface) and biochemical (protein content, alkaline phosphatase and leucine aminopeptidase activities) aspects of the mucosa were assessed along the whole small intestine. The presence of a small number of worms induced only minor mucosal changes, indicating a regenerative response of the intestinal epithelium. The role of a local small population of T. colubriformis in the development of a previously described adaptive response appeared thus to be limited. On the other hand, the 50,000 L3 inoculum was associated with severe lesions of villi, marked crypt hyperplasia and with a major reduction of enzyme activities. The changes were found along the whole length of the small intestine. These results suggest that the generally recognized dose-dependent pathogenicity of the intestinal nematode infections could be ascribed to two different processes: firstly, a greater severity of the lesions; secondly, more extensive damage leading to the disappearance of any adaptive intestinal region.

Comparison of transepithelial corneal crosslinking with epithelium-off crosslinking (epithelium-off CXL in adult Pakistani population with progressive keratoconus

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Bushra Akbar

2017-01-01

CONCLUSION: Transepithelial CXL is not recommended to be replaced completely by standard epithelium-off CXL due to continued ectatic progression in 25% of cases. However, thin corneas, unfit for standard epithelium-off CXL, can benefit from transepithelial CXL.

The role of CDX2 in intestinal homeostasis and inflammation

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Coskun, Mehmet; Troelsen, Jesper Thorvald; Nielsen, Ole Haagen

2011-01-01

a causal role in a large number of diseases and developmental disorders. Inflammatory bowel disease (IBD) is characterized by a chronically inflamed mucosa caused by dysregulation of the intestinal immune homeostasis. The aetiology of IBD is thought to be a combination of genetic and environmental factors......, including luminal bacteria. The Caudal-related homeobox transcription factor 2 (CDX2) is critical in early intestinal differentiation and has been implicated as a master regulator of the intestinal homeostasis and permeability in adults. When expressed, CDX2 modulates a diverse set of processes including...... of the intestinal homeostasis and further to reveal its potential role in inflammation....

A hypermorphic epithelial β-catenin mutation facilitates intestinal tumorigenesis in mice in response to compounding WNT-pathway mutations

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Michael Buchert

2015-11-01

Full Text Available Activation of the Wnt/β-catenin pathway occurs in the vast majority of colorectal cancers. However, the outcome of the disease varies markedly from individual to individual, even within the same tumor stage. This heterogeneity is governed to a great extent by the genetic make-up of individual tumors and the combination of oncogenic mutations. In order to express throughout the intestinal epithelium a degradation-resistant β-catenin (Ctnnb1, which lacks the first 131 amino acids, we inserted an epitope-tagged ΔN(1-131-β-catenin-encoding cDNA as a knock-in transgene into the endogenous gpA33 gene locus in mice. The resulting gpA33ΔN-Bcat mice showed an increase in the constitutive Wnt/β-catenin pathway activation that shifts the cell fate towards the Paneth cell lineage in pre-malignant intestinal epithelium. Furthermore, 19% of all heterozygous and 37% of all homozygous gpA33ΔN-Bcat mice spontaneously developed aberrant crypt foci and adenomatous polyps, at frequencies and latencies akin to those observed in sporadic colon cancer in humans. Consistent with this, the Wnt target genes, MMP7  and Tenascin-C, which are most highly expressed in benign human adenomas and early tumor stages, were upregulated in pre-malignant tissue of gpA33ΔN-Bcat mice, but those Wnt target genes associated with excessive proliferation (i.e. Cdnn1, myc were not. We also detected diminished expression of membrane-associated α-catenin and increased intestinal permeability in gpA33ΔN-Bcat mice in challenge conditions, providing a potential explanation for the observed mild chronic intestinal inflammation and increased susceptibility to azoxymethane and mutant Apc-dependent tumorigenesis. Collectively, our data indicate that epithelial expression of ΔN(1-131-β-catenin in the intestine creates an inflammatory microenvironment and co-operates with other mutations in the Wnt/β-catenin pathway to facilitate and promote tumorigenesis.

Molecular and functional expression of high conductance Ca 2+ activated K+ channels in the eel intestinal epithelium

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Lionetto, Maria G; Rizzello, Antonia; Giordano, Maria E

2008-01-01

Several types of K(+) channels have been identified in epithelial cells. Among them high conductance Ca(2+)-activated K(+) channels (BK channels) are of relevant importance for their involvement in regulatory volume decrease (RVD) response following hypotonic stress. The aim of the present work...... was to investigate the functional and molecular expression of BK in the eel intestine, which is a useful experimental model for cell volume regulation research. In the present paper using rat BK channel-specific primer, a RT-PCR signal of 696 pb cDNA was detected in eel intestine, whole nucleotide sequence showed...... high similarity (83%) to the alpha subunit of BK channel family. BK channel protein expression was verified by immunoblotting and confocal microscopy, while the functional role of BK channels in epithelial ion transport mechanisms and cell volume regulation was examined by electrophysiological...

Neoplasia versus hyperplasia of the retinal pigment epithelium

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Heegaard, Steffen; Larsen, J.N.B.; Fledelius, Hans C.

2001-01-01

ophthalmology, retinal pigment epithelium, adenoma, tumor-like hyperplasia, histology, immunohistochemistry, tumor, neoplasm, ultrasonography......ophthalmology, retinal pigment epithelium, adenoma, tumor-like hyperplasia, histology, immunohistochemistry, tumor, neoplasm, ultrasonography...

Epithelial WNT Ligands Are Essential Drivers of Intestinal Stem Cell Activation

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Winnie Y. Zou

2018-01-01

Full Text Available Intestinal stem cells (ISCs maintain and repair the intestinal epithelium. While regeneration after ISC-targeted damage is increasingly understood, injury-repair mechanisms that direct regeneration following injuries to differentiated cells remain uncharacterized. The enteric pathogen, rotavirus, infects and damages differentiated cells while sparing all ISC populations, thus allowing the unique examination of the response of intact ISC compartments during injury-repair. Upon rotavirus infection in mice, ISC compartments robustly expand and proliferating cells rapidly migrate. Infection results specifically in stimulation of the active crypt-based columnar ISCs, but not alternative reserve ISC populations, as is observed after ISC-targeted damage. Conditional ablation of epithelial WNT secretion diminishes crypt expansion and ISC activation, demonstrating a previously unknown function of epithelial-secreted WNT during injury-repair. These findings indicate a hierarchical preference of crypt-based columnar cells (CBCs over other potential ISC populations during epithelial restitution and the importance of epithelial-derived signals in regulating ISC behavior.

CD34+ mesenchymal cells are a major component of the intestinal stem cells niche at homeostasis and after injury.

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Stzepourginski, Igor; Nigro, Giulia; Jacob, Jean-Marie; Dulauroy, Sophie; Sansonetti, Philippe J; Eberl, Gérard; Peduto, Lucie

2017-01-24

The intestinal epithelium is continuously renewed by intestinal epithelial stem cells (IESCs) positioned at the base of each crypt. Mesenchymal-derived factors are essential to maintain IESCs; however, the cellular composition and development of such mesenchymal niche remains unclear. Here, we identify pericryptal CD34 + Gp38 + αSMA - mesenchymal cells closely associated with Lgr5 + IESCs. We demonstrate that CD34 + Gp38 + cells are the major intestinal producers of the niche factors Wnt2b, Gremlin1, and R-spondin1, and are sufficient to promote maintenance of Lgr5 + IESCs in intestinal organoids, an effect mainly mediated by Gremlin1. CD34 + Gp38 + cells develop after birth in the intestinal submucosa and expand around the crypts during the third week of life in mice, independently of the microbiota. We further show that pericryptal CD34 + gp38 + cells are rapidly activated by intestinal injury, up-regulating niche factors Gremlin1 and R-spondin1 as well as chemokines, proinflammatory cytokines, and growth factors with key roles in gut immunity and tissue repair, including IL-7, Ccl2, Ptgs2, and Amphiregulin. Our results indicate that CD34 + Gp38 + mesenchymal cells are programmed to develop in the intestine after birth to constitute a specialized microenvironment that maintains IESCs at homeostasis and contribute to intestinal inflammation and repair after injury.

Prevalence of ciliated epithelium in apical periodontitis lesions.

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Ricucci, Domenico; Loghin, Simona; Siqueira, José F; Abdelsayed, Rafik A

2014-04-01

This article reports on the morphologic features and the frequency of ciliated epithelium in apical cysts and discusses its origin. The study material consisted of 167 human apical periodontitis lesions obtained consecutively from patients presenting for treatment during a period of 12 years in a dental practice operated by one of the authors. All of the lesions were obtained still attached to the root apices of teeth with untreated (93 lesions) or treated canals (74 lesions). The former were obtained by extraction and the latter by extraction or apical surgery. Specimens were processed for histopathologic and histobacteriologic analyses. Lesions were classified, and the type of epithelium, if present, was recorded. Of the lesions analyzed, 49 (29%) were diagnosed as cysts. Of these, 26 (53%) were found in untreated teeth, and 23 (47%) related to root canal-treated teeth. Ciliated columnar epithelium was observed partially or completely lining the cyst wall in 4 cysts, and all of them occurred in untreated maxillary molars. Three of these lesions were categorized as pocket cysts, and the other was a true cyst. Ciliated columnar epithelium-lined cysts corresponded to approximately 2% of the apical periodontitis lesions and 8% of the cysts of endodontic origin in the population studied. This epithelium is highly likely to have a sinus origin in the majority of cases. However, the possibility of prosoplasia or upgraded differentiation into ciliated epithelium from the typical cystic lining squamous epithelium may also be considered. Copyright © 2014 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Cytokine gene expression in intestine of rat during the postnatal developmental period: increased IL-1 expression at weaning.

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Mengheri, E; Ciapponi, L; Vignolini, F; Nobili, F

1996-01-01

In the present study we have investigate whether cytokines are constitutively and differently expressed in intestine during the differentiative processes that take place at weaning. We have analyzed the expression of IL-1 beta, IL-2, IL-4 and IFN gamma by polymerase chain reaction in Peyer's patches (PP) and in intestine deprived of PP (I-PP) of rats from 16 to 30 days of age. The results showed a constitutive and marked expression of the cytokines already before weaning, with the exception of IL-2 in PP and IFN gamma in I-PP. IL-beta was the only cytokine to show a different expression at various ages with an initial increase at 19 days and a further elevation at 21 days when intestinal epithelium passes through major differentiative stages, suggesting an involvement of this cytokine in intestinal development. We have also tested whether treatment of rats with the immunosuppressor cyclosporin A (CsA) could affect intestinal differentiation. The results showed that only some markers of differentiation were affected (proliferation of staminal crypt cells and length of crypts). This was probably due to a direct effect rather than an immunomediated effect of CsA, since treatment of three intestinal cell lines (Caco-2, HT-29, FRIC) with CsA indicated that this drug can exert a cytostatic activity on intestinal cells.

Actin-interacting protein 1 controls assembly and permeability of intestinal epithelial apical junctions.

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Lechuga, Susana; Baranwal, Somesh; Ivanov, Andrei I

2015-05-01

Adherens junctions (AJs) and tight junctions (TJs) are crucial regulators of the integrity and restitution of the intestinal epithelial barrier. The structure and function of epithelial junctions depend on their association with the cortical actin cytoskeleton that, in polarized epithelial cells, is represented by a prominent perijunctional actomyosin belt. The assembly and stability of the perijunctional cytoskeleton is controlled by constant turnover (disassembly and reassembly) of actin filaments. Actin-interacting protein (Aip) 1 is an emerging regulator of the actin cytoskeleton, playing a critical role in filament disassembly. In this study, we examined the roles of Aip1 in regulating the structure and remodeling of AJs and TJs in human intestinal epithelium. Aip1 was enriched at apical junctions in polarized human intestinal epithelial cells and normal mouse colonic mucosa. Knockdown of Aip1 by RNA interference increased the paracellular permeability of epithelial cell monolayers, decreased recruitment of AJ/TJ proteins to steady-state intercellular contacts, and attenuated junctional reassembly in a calcium-switch model. The observed defects of AJ/TJ structure and functions were accompanied by abnormal organization and dynamics of the perijunctional F-actin cytoskeleton. Moreover, loss of Aip1 impaired the apico-basal polarity of intestinal epithelial cell monolayers and inhibited formation of polarized epithelial cysts in 3-D Matrigel. Our findings demonstrate a previously unanticipated role of Aip1 in regulating the structure and remodeling of intestinal epithelial junctions and early steps of epithelial morphogenesis. Copyright © 2015 the American Physiological Society.

Increase of corneal epithelium cell radioresistance during regeneration

International Nuclear Information System (INIS)

Popova, M.F.; Bulyakova, N.V.; Azarova, V.S.

1985-01-01

A comparative study of the radiosensitivity of the normal and regenerating cornea epithelium of C 57 Bl mice was performed on the cellular level, the duration of the cell cycle being taken into account. Criteria of radiation injuries were the number of chromosome aberrations, mitotic index and duration of mitotic block. The anterior part of the head was irradiated singly with 1.75, 3.5 or 7.0 Gy and also repeatedly 3.5 + 3.5 at a 24-hours interval. The corneas were fixed 2, 4, 6, 12, 24, 48, 72 and 96 hours after irradiation. In all cases of irradiated mice the regenerating epithelium showed a shorter mitotic block and significantly lower cytogenetic injury as compared with the controls. Effects of fractionated irradiation were only shown in the regenerating epithelium. The results obtained indicate that regenerating epithelium cells of the cornea are significantly more radioresistant than normal epithelium due to activation of post-radiation recovery, and also, possibly, due to an increase in the content of endogenous radioprotectors. (author)

Acid phosphatase and lipid peroxidation in human cataractous lens epithelium

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Vasavada Abhay

1993-01-01

Full Text Available The anterior lens epithelial cells undergo a variety of degenerative and proliferative changes during cataract formation. Acid phosphatase is primarily responsible for tissue regeneration and tissue repair. The lipid hydroperoxides that are obtained by lipid peroxidation of polysaturated or unsaturated fatty acids bring about deterioration of biological membranes at cellular and tissue levels. Acid phosphatase and lipid peroxidation activities were studied on the lens epithelial cells of nuclear cataract, posterior subcapsular cataract, mature cataract, and mixed cataract. Of these, mature cataractous lens epithelium showed maximum activity for acid phosphatase (516.83 moles of p-nitrophenol released/g lens epithelium and maximum levels of lipid peroxidation (86.29 O.D./min/g lens epithelium. In contrast, mixed cataractous lens epithelium showed minimum activity of acid phosphatase (222.61 moles of p-nitrophenol released/g lens epithelium and minimum levels of lipid peroxidation (54.23 O.D./min/g lens epithelium. From our study, we correlated the maximum activity of acid phosphatase in mature cataractous lens epithelium with the increased areas of superimposed cells associated with the formation of mature cataract. Likewise, the maximum levels of lipid peroxidation in mature cataractous lens epithelium was correlated with increased permeability of the plasma membrane. Conversely, the minimum levels of lipid peroxidation in mixed cataractous lens epithelium makes us presume that factors other than lipid peroxidation may also account for the formation of mixed type of cataract.

Deoxynivalenol as a contaminant of broiler feed: intestinal development, absorptive functionality, and metabolism of the mycotoxin.

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Yunus, A W; Blajet-Kosicka, A; Kosicki, R; Khan, M Z; Rehman, H; Böhm, J

2012-04-01

Deoxynivalenol (DON) has been recently documented to deteriorate intestinal morphology in chickens at dietary doses that are regarded as safe for this species. The present trial was conducted to explore the significance of these morphological changes in relation to intestinal absorptive functionality and DON metabolism. Ross broilers at 7 d of age were fed either a basal diet (0.265 ± 0.048 mg of DON/kg; 0.013 ± 0.001 mg of zearalenone/kg), a low DON diet (1.68 mg of DON/kg; 0.145 ± 0.007 mg of zearalenone/kg), or a high DON diet (12.209 ± 1.149 mg of DON/kg; 1.094 ± 0.244 mg of zearalenone/kg). The DON diets (to variable degrees) progressively decreased the relative density (weight:length) of the small intestine with increasing exposure length, which could be correlated with a decrease in villus height in the small intestine. Short circuit current of the jejunal epithelium, reflecting transport function of the epithelium per unit area, was reduced (P = 0.001) in the birds fed the high DON diet. The increasing dietary level of DON linearly (P = 0.035) increased the length of the jejunum in wk 4 of exposure, resulting in conservation of macronutrient retention. Upon challenging the birds with a fixed amount of DON after wk 5 of exposure, higher (P ≤ 0.033) amounts of DON and the detoxification metabolite (de-epoxy-DON) were found at 5 h postchallenge in the guts of birds raised on the DON diets. The increasing level of previous exposure to DON linearly (P = 0.040) decreased the plasma level of DON in the birds at 1 h postchallenge. The amounts of zearalenone and its analogs in the gut and plasma also followed a trend similar to that for DON. These data suggest that intestines in chickens may adapt to a chronic DON challenge by morphological and functional modifications. The birds having previous exposure to Fusarium mycotoxins showed moderate detoxification coupled with reduced transfer of the mycotoxins to systemic circulation. Some metabolites of

Effects of the ionising radiations on the structure and the function of the intestinal epithelial cell

International Nuclear Information System (INIS)

Haton, C.

2005-06-01

The intestinal mucosa is a particularly radio-sensitive tissue and damage may occur following either accidental or therapeutic exposure. the deleterious actions of ionizing radiation are linked to the formation of sometimes overwhelming quantities of reactive oxygen species (R.O.S.). Production of R.O.S. is both direct and indirect from the secondary effects of irradiation. A better comprehension of the underlying mechanisms of injury will lead to more adapted therapeutic approaches to limit the harmful effects of irradiation. The homeostasis of the intestinal epithelium is regulated by three factors: proliferation, apoptosis and differentiation. these three factors were studied using the cell model, HT29, in order to analyze modulations of this balance after irradiation. our results, in agreement with other data, showed the establishment of mitotic delay. This arrest of proliferation was followed by apoptosis to be the major mechanism leading to cell death in this model. thus, for the first time, we have shown that irradiated intestinal epithelial cells preserve their capacity to differentiate. This indicates, although indirectly, that intestinal cells have and preserve an intrinsic capacity restore a functional epithelium. R.O.S. are considered as intermediates between the physical nature of radiations and biological responses. It seems essential to understand anti-oxidant mechanisms used by the cell for defence against the deleterious effects of R.O.S post exposure. This study of several anti-oxidant defence mechanisms of intestinal mucosa, was carried out in vivo in the mouse at different times following abdominal irradiation. We observed an early mitochondrial response in the hours following irradiation revealing this organelle as a particular target. We demonstrated a strong alteration of anti-oxidant capacity as revealed by a decrease in S.O.D.s, catalase and an increase of the G.P.X.s and M.T.s. A part of these modifications appeared to depend on an

Autoradiographic investigation of age-dependent proliferation kinetics in the mucosa of rat small intestine

International Nuclear Information System (INIS)

Kranz, D.; Laue, R.; Fuhrmann, I.

1980-01-01

Aging of cells depends on mitotic activity which is particularly evident in multicellular organisms. The cell kinetics of the mucosa of the small intestine in a total of 244 Wistar rats aged 6 days, 6 weeks, 6, 12, 23 and 28 months, resp., were studied histoautoradiographically. It could be demonstrated that the regeneration rate of cells per hour in the crypts of the small intestine and the migration velocity of the enterocytes differ in young and old individuals, and that the intermitotic cells have age-dependent properties as well. In addition, it could be proved that intermitotic cells have a non growth fraction, too, which, at an advanced age, decreases only slightly although significantly in terms of statistics. For the easily vulnerable crypt epithelium it is a reserve capacity and ban be included in the proliferating pool if necessary. (author)

Analysis of the Sodium Recirculation Theory of Solute Coupled Water Transport in Small Intestine

DEFF Research Database (Denmark)

Larsen, E. H.; Sørensen, Jens Nørkær; Sørensen, J. B.

2002-01-01

Our previous mathematical model of solute-coupled water transport through the intestinal epithelium is extended for dealing with electrolytes rather than electroneutral solutes. A 3Na+-2K+ pump in the lateral membranes provides the energy-requiring step for driving transjunctional and translateral......, computations predict that the concentration differences between lis and bathing solutions are small for all three ions. Nevertheless, the diffusion fluxes of the ions out of lis significantly exceed their mass transports. It is concluded that isotonic transport requires recirculation of all three ions....... The computed sodium recirculation flux that is required for isotonic transport corresponds to that estimated in experiments on toad small intestine. This result is shown to be robust and independent of whether the apical entrance mechanism for the sodium ion is a channel, a SGLT1 transporter driving inward...

Review: Exogenous butyrate: implications for the functional development of ruminal epithelium and calf performance.

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Niwińska, B; Hanczakowska, E; Arciszewski, M B; Klebaniuk, R

2017-09-01

The importance of the use of exogenous butyrate in calves' diets is due to its role as a factor stimulating the functional development of ruminal epithelium and improving calf performance during the transition from preruminant to ruminant status. Our review will first present results related to effects of the administration of butyrate in calves' diets on the development of ruminal epithelium toward a more effective absorption and metabolism of fermentation products from the rumen. The introduction of sodium butyrate at a level of about 0.3% of diet dry matter is accompanied by an increase to 35% in butyrate concentration in the rumen of 33-day-old calves. Mutual reliance between an enhanced ruminal concentration of butyrate and the activities of transcription factors, genes and proteins involved in cell proliferation, ketogenesis and the maintenance of cell pH homeostasis in the ruminal epithelial cells has been clearly confirmed in many experiments. Second, the review presents results related to the effects of the introduction of butyrate salts in the diet on calf performance. Of 11 studies a positive effect was found in six; five of these were obtained from the calves that started receiving butyrate supplement at a level of about 0.3% diet dry matter from the age of 3 to 5 days. Results indicate that when a supplement is given to calves soon after birth the functional development of ruminal epithelium in cooperation with the endocrine and digestion systems is transferred into improving the efficiency of rearing. There have been no studies on the effects of greater amounts of butyrate salts in milk replacer; butyrate constitutes about 1.2% of the whole cow's milk dry matter. In older calves, when butyrate administration is provided as a component of a starter concentrate at the increasing inclusion rate from 0.3% to 3.0%, the practical effect in calf performance relates to the risk of depression of rumen pH below 5.5 and accompanying disruption of the

Physiological, Pathological, and Therapeutic Implications of Zonulin-Mediated Intestinal Barrier Modulation

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Fasano, Alessio

2008-01-01

The anatomical and functional arrangement of the gastrointestinal tract suggests that this organ, beside its digestive and absorptive functions, regulates the trafficking of macromolecules between the environment and the host through a barrier mechanism. Under physiological circumstances, this trafficking is safeguarded by the competency of intercellular tight junctions, structures whose physiological modulation is mediated by, among others, the recently described protein zonulin. To prevent harm and minimize inflammation, the same paracellular pathway, in concert with the gut-associated lymphoid tissue and the neuroendocrine network, controls the equilibrium between tolerance and immunity to nonself antigens. The zonulin pathway has been exploited to deliver drugs, macromolecules, or vaccines that normally would not be absorbed through the gastrointestinal mucosal barrier. However, if the tightly regulated trafficking of macromolecules is jeopardized secondary to prolonged zonulin up-regulation, the excessive flow of nonself antigens in the intestinal submucosa can cause both intestinal and extraintestinal autoimmune disorders in genetically susceptible individuals. This new paradigm subverts traditional theories underlying the development of autoimmunity, which are based on molecular mimicry and/or the bystander effect, and suggests that the autoimmune process can be arrested if the interplay between genes and environmental triggers is prevented by re-establishing intestinal barrier competency. Understanding the role of zonulin-dependent intestinal barrier dysfunction in the pathogenesis of autoimmune diseases is an area of translational research that encompasses many fields. PMID:18832585

Indispensable role of Notch ligand-dependent signaling in the proliferation and stem cell niche maintenance of APC-deficient intestinal tumors

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Nakata, Toru; Shimizu, Hiromichi; Nagata, Sayaka; Ito, Go; Fujii, Satoru; Suzuki, Kohei; Kawamoto, Ami; Ishibashi, Fumiaki; Kuno, Reiko; Anzai, Sho; Murano, Tatsuro; Mizutani, Tomohiro; Oshima, Shigeru; Tsuchiya, Kiichiro; Nakamura, Tetsuya; Hozumi, Katsuto; Watanabe, Mamoru; Okamoto, Ryuichi

2017-01-01

Ligand-dependent activation of Notch signaling is required to maintain the stem-cell niche of normal intestinal epithelium. However, the precise role of Notch signaling in the maintenance of the intestinal tumor stem cell niche and the importance of the RBPJ-independent non-canonical pathway in intestinal tumors remains unknown. Here we show that Notch signaling was activated in LGR5 +ve cells of APC-deficient mice intestinal tumors. Accordingly, Notch ligands, including Jag1, Dll1, and Dll4, were expressed in these tumors. In vitro studies using tumor-derived organoids confirmed the intrinsic Notch activity-dependent growth of tumor cells. Surprisingly, the targeted deletion of Jag1 but not RBPJ in LGR5 +ve tumor-initiating cells resulted in the silencing of Hes1 expression, disruption of the tumor stem cell niche, and dramatic reduction in the proliferation activity of APC-deficient intestinal tumors in vivo. Thus, our results highlight the importance of ligand-dependent non-canonical Notch signaling in the proliferation and maintenance of the tumor stem cell niche in APC-deficient intestinal adenomas. - Highlights: • Notch signaling is activated in LGR5 +ve cells of APC-deficient intestinal tumors. • Lack of Jag1 but not RBPJ disrupts stem cell niche formation in those tumors. • Lack of Jag1 reduces the proliferation activity of APC-deficient intestinal tumors.

The chronicles of Porphyromonas gingivalis: the microbium, the human oral epithelium and their interplay.

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Yilmaz, Ozlem

2008-10-01

The microbiota of the human oral mucosa consists of a myriad of bacterial species that normally exist in commensal harmony with the host. Porphyromonas gingivalis, an aetiological agent in severe forms of periodontitis (a chronic inflammatory disease), is a prominent component of the oral microbiome and a successful colonizer of the oral epithelium. This Gram-negative anaerobe can also exist within the host epithelium without the existence of overt disease. Gingival epithelial cells, the outer lining of the gingival mucosa, which function as an important part of the innate immune system, are among the first host cells colonized by P. gingivalis. This review describes recent studies implicating the co-existence and intracellular adaptation of the organism in these target host cells. Specifically, recent findings on the putative mechanisms of persistence, intercellular dissemination and opportunism are highlighted. These new findings may also represent an original and valuable model for mechanistic characterization of other successful host-adapted, self-limiting, persistent intracellular bacteria in human epithelial tissues.

Morphological and molecular evidence for functional organization along the rostrocaudal axis of the adult zebrafish intestine

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Lam Siew

2010-06-01

Full Text Available Abstract Background The zebrafish intestine is a simple tapered tube that is folded into three sections. However, whether the intestine is functionally similar along its length remains unknown. Thus, a systematic structural and functional characterization of the zebrafish intestine is desirable for future studies of the digestive tract and the intestinal biology and development. Results To characterize the structure and function of the adult zebrafish intestine, we divided the intestine into seven roughly equal-length segments, S1-S7, and systematically examined the morphology of the mucosal lining, histology of the epithelium, and molecular signatures from transcriptome analysis. Prominent morphological features are circumferentially-oriented villar ridges in segments S1-S6 and the absence of crypts. Molecular characterization of the transcriptome from each segment shows that segments S1-S5 are very similar while S6 and S7 unique. Gene ontology analyses reveal that S1-S5 express genes whose functions involve metabolism of carbohydrates, transport of lipids and energy generation, while the last two segments display relatively limited function. Based on comparative Gene Set Enrichment Analysis, the first five segments share strong similarity with human and mouse small intestine while S6 shows similarity with human cecum and rectum, and S7 with human rectum. The intestinal tract does not display the anatomical, morphological, and molecular signatures of a stomach and thus we conclude that this organ is absent from the zebrafish digestive system. Conclusions Our genome-wide gene expression data indicate that, despite the lack of crypts, the rostral, mid, and caudal portions of the zebrafish intestine have distinct functions analogous to the mammalian small and large intestine, respectively. Organization of ridge structures represents a unique feature of zebrafish intestine, though they produce similar cross sections to mammalian intestines

Interleukin-15 promotes intestinal dysbiosis with butyrate deficiency associated with increased susceptibility to colitis

Energy Technology Data Exchange (ETDEWEB)

Meisel, Marlies; Mayassi, Toufic; Fehlner-Peach, Hannah; Koval, Jason C.; O' Brien, Sarah L.; Hinterleitner, Reinhard; Lesko, Kathryn; Kim, Sangman; Bouziat, Romain; Chen, Li; Weber, Christopher R.; Mazmanian, Sarkis K.; Jabri, Bana; Antonopoulos, Dionysios A.

2016-09-20

Dysbiosis resulting in gut-microbiome alterations with reduced butyrate production are thought to disrupt intestinal immune homeostasis and promote complex immune disorders. However, whether and how dysbiosis develops before the onset of overt pathology remains poorly defined. Interleukin 15 (IL-15) is upregulated in distressed tissue and its overexpression is thought to predispose susceptible individuals to and play a role in the pathogenesis of celiac disease and inflammatory bowel disease (IBD). While the immunological roles of IL-15 have been largely studied, its potential impact on the microbiota remains unexplored. Analysis of 16S rRNA-based inventories of bacterial communities in mice overexpressing IL-15 in the intestinal epithelium (v-IL-15tg mice) shows distinct changes in the composition of the intestinal bacteria. While some alterations are specific to individual intestinal compartments, others are found across the ileum, cecum, and feces. In particular, IL-15 overexpression restructures the composition of the microbiota with a decrease in butyrate producing bacteria that is associated with a reduction in luminal butyrate levels across all intestinal compartments. Fecal microbiota transplant experiments of wild-type and v-IL-15tg microbiota into germ-free mice further indicate that diminishing butyrate concentration observed in the intestinal lumen of v-IL-15tg mice is the result of intrinsic alterations in the microbiota induced by IL-15. This reconfiguration of the microbiota is associated with increased susceptibility to dextran sodium sulfate induced colitis. Altogether, this study reveals that IL-15 impacts butyrate-producing bacteria and lowers butyrate levels in the absence of overt pathology, which represent events that precede and promote intestinal inflammatory diseases.

Kaiso overexpression promotes intestinal inflammation and potentiates intestinal tumorigenesis in Apc(Min/+) mice.

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Pierre, Christina C; Longo, Joseph; Mavor, Meaghan; Milosavljevic, Snezana B; Chaudhary, Roopali; Gilbreath, Ebony; Yates, Clayton; Daniel, Juliet M

2015-09-01

Constitutive Wnt/β-catenin signaling is a key contributor to colorectal cancer (CRC). Although inactivation of the tumor suppressor adenomatous polyposis coli (APC) is recognized as an early event in CRC development, it is the accumulation of multiple subsequent oncogenic insults facilitates malignant transformation. One potential contributor to colorectal carcinogenesis is the POZ-ZF transcription factor Kaiso, whose depletion extends lifespan and delays polyp onset in the widely used Apc(Min/+) mouse model of intestinal cancer. These findings suggested that Kaiso potentiates intestinal tumorigenesis, but this was paradoxical as Kaiso was previously implicated as a negative regulator of Wnt/β-catenin signaling. To resolve Kaiso's role in intestinal tumorigenesis and canonical Wnt signaling, we generated a transgenic mouse model (Kaiso(Tg/+)) expressing an intestinal-specific myc-tagged Kaiso transgene. We then mated Kaiso(Tg/+) and Apc(Min/+) mice to generate Kaiso(Tg/+):Apc(Min/+) mice for further characterization. Kaiso(Tg/+):Apc(Min/+) mice exhibited reduced lifespan and increased polyp multiplicity compared to Apc(Min/+) mice. Consistent with this murine phenotype, we found increased Kaiso expression in human CRC tissue, supporting a role for Kaiso in human CRC. Interestingly, Wnt target gene expression was increased in Kaiso(Tg/+):Apc(Min/+) mice, suggesting that Kaiso's function as a negative regulator of canonical Wnt signaling, as seen in Xenopus, is not maintained in this context. Notably, Kaiso(Tg/+):Apc(Min/+) mice exhibited increased inflammation and activation of NFκB signaling compared to their Apc(Min/+) counterparts. This phenotype was consistent with our previous report that Kaiso(Tg/+) mice exhibit chronic intestinal inflammation. Together our findings highlight a role for Kaiso in promoting Wnt signaling, inflammation and tumorigenesis in the mammalian intestine. Copyright © 2015 Elsevier B.V. All rights reserved.

Colon-specific delivery of a probiotic-derived soluble protein ameliorates intestinal inflammation in mice through an EGFR-dependent mechanism

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Yan, Fang; Cao, Hanwei; Cover, Timothy L.; Washington, M. Kay; Shi, Yan; Liu, LinShu; Chaturvedi, Rupesh; Peek, Richard M.; Wilson, Keith T.; Polk, D. Brent

2011-01-01

Probiotic bacteria can potentially have beneficial effects on the clinical course of several intestinal disorders, but our understanding of probiotic action is limited. We have identified a probiotic bacteria–derived soluble protein, p40, from Lactobacillus rhamnosus GG (LGG), which prevents cytokine-induced apoptosis in intestinal epithelial cells. In the current study, we analyzed the mechanisms by which p40 regulates cellular responses in intestinal epithelial cells and p40’s effects on experimental colitis using mouse models. We show that the recombinant p40 protein activated EGFR, leading to Akt activation. Activation of EGFR by p40 was required for inhibition of cytokine-induced apoptosis in intestinal epithelial cells in vitro and ex vivo. Furthermore, we developed a pectin/zein hydrogel bead system to specifically deliver p40 to the mouse colon, which activated EGFR in colon epithelial cells. Administration of p40-containing beads reduced intestinal epithelial apoptosis and disruption of barrier function in the colon epithelium in an EGFR-dependent manner, thereby preventing and treating DSS-induced intestinal injury and acute colitis. Furthermore, p40 activation of EGFR was required for ameliorating colon epithelial cell apoptosis and chronic inflammation in oxazolone-induced colitis. These data define what we believe to be a previously unrecognized mechanism of probiotic-derived soluble proteins in protecting the intestine from injury and inflammation. PMID:21606592

EGFR/Ras Signaling Controls Drosophila Intestinal Stem Cell Proliferation via Capicua-Regulated Genes.

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Yinhua Jin

2015-12-01

Full Text Available Epithelial renewal in the Drosophila intestine is orchestrated by Intestinal Stem Cells (ISCs. Following damage or stress the intestinal epithelium produces ligands that activate the epidermal growth factor receptor (EGFR in ISCs. This promotes their growth and division and, thereby, epithelial regeneration. Here we demonstrate that the HMG-box transcriptional repressor, Capicua (Cic, mediates these functions of EGFR signaling. Depleting Cic in ISCs activated them for division, whereas overexpressed Cic inhibited ISC proliferation and midgut regeneration. Epistasis tests showed that Cic acted as an essential downstream effector of EGFR/Ras signaling, and immunofluorescence showed that Cic's nuclear localization was regulated by EGFR signaling. ISC-specific mRNA expression profiling and DNA binding mapping using DamID indicated that Cic represses cell proliferation via direct targets including string (Cdc25, Cyclin E, and the ETS domain transcription factors Ets21C and Pointed (pnt. pnt was required for ISC over-proliferation following Cic depletion, and ectopic pnt restored ISC proliferation even in the presence of overexpressed dominant-active Cic. These studies identify Cic, Pnt, and Ets21C as critical downstream effectors of EGFR signaling in Drosophila ISCs.

The application of fluorescence in situ hybridization (FISH technique for studying the microbial communities in intestinal tissues of white shrimp (Penaeus vannamei

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Supamattaya, K.

2005-02-01

Full Text Available Fluorescence in situ hybridization technique is very useful for the evaluation of microbial communities in various environments. It is possible to apply this technique to study the intestinal microflora in white shrimp (Penaeus vannamei. Different fixatives and storage temperature were tested in this technique. It was found that fixation with 10% buffered formalin for 12 hours and changed to 70% ethanol shown positive results when compared to the fixation with Davidson's fixative or RF fixative. The best signaling was obtainedfrom the samples which were stored in -20ºC. By using the DNA probe targeted to the Eubacteria domain (EUB338 probe, 5′-GCT GCC TCC CGT AGG AGT-3′ labeled with fluorescein as a hybridizing probe, it was found that most intestinal microflora were aggregated with the intestinal contents, or dispersed in the lumen. There was not evidence of the attachment of the microflora with the intestinal epithelium in this study.

Hair cell regeneration in the avian auditory epithelium.

Science.gov (United States)

Stone, Jennifer S; Cotanche, Douglas A

2007-01-01

Regeneration of sensory hair cells in the mature avian inner ear was first described just over 20 years ago. Since then, it has been shown that many other non-mammalian species either continually produce new hair cells or regenerate them in response to trauma. However, mammals exhibit limited hair cell regeneration, particularly in the auditory epithelium. In birds and other non-mammals, regenerated hair cells arise from adjacent non-sensory (supporting) cells. Hair cell regeneration was initially described as a proliferative response whereby supporting cells re-enter the mitotic cycle, forming daughter cells that differentiate into either hair cells or supporting cells and thereby restore cytoarchitecture and function in the sensory epithelium. However, further analyses of the avian auditory epithelium (and amphibian vestibular epithelium) revealed a second regenerative mechanism, direct transdifferentiation, during which supporting cells change their gene expression and convert into hair cells without dividing. In the chicken auditory epithelium, these two distinct mechanisms show unique spatial and temporal patterns, suggesting they are differentially regulated. Current efforts are aimed at identifying signals that maintain supporting cells in a quiescent state or direct them to undergo direct transdifferentiation or cell division. Here, we review current knowledge about supporting cell properties and discuss candidate signaling molecules for regulating supporting cell behavior, in quiescence and after damage. While significant advances have been made in understanding regeneration in non-mammals over the last 20 years, we have yet to determine why the mammalian auditory epithelium lacks the ability to regenerate hair cells spontaneously and whether it is even capable of significant regeneration under additional circumstances. The continued study of mechanisms controlling regeneration in the avian auditory epithelium may lead to strategies for inducing

Diet and the intestinal microbiome: associations, functions, and implications for health and disease.

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Albenberg, Lindsey G; Wu, Gary D

2014-05-01

The mutual relationship between the intestinal microbiota and its mammalian host is influenced by diet. Consumption of various nutrients affects the structure of the microbial community and provides substrates for microbial metabolism. The microbiota can produce small molecules that are absorbed by the host and affect many important physiological processes. Age-dependent and societal differences in the intestinal microbiota could result from differences in diet. Examples include differences in the intestinal microbiota of breastfed vs formula-fed infants or differences in microbial richness in people who consume an agrarian plant-based vs a Western diet, which is high in meat and fat. We review how diet affects the structure and metabolome of the human intestinal microbiome and may contribute to health or the pathogenesis of disorders such as coronary vascular disease and inflammatory bowel disease. Copyright © 2014 AGA Institute. Published by Elsevier Inc. All rights reserved.

Oestrus synchronization treatment induces histomorphological changes on the uterine tube epithelium of the gilt.

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Juárez-Mosqueda, M L; Anzaldúa Arce, S R; Palma Lara, I; García Dalmán, C; Cornejo Cortés, M A; Córdova Izquierdo, A; Villaseñor Gaona, H; Trujillo Ortega, M E

2015-12-01

-positive and PAS-negative cells, and the epithelium height. This has influence in the secretory activity of the epithelium and possibly alters the fluid microenvironment of the gilt's uterine tube. The biological impact of regional variations in the epithelial cells of the gilt's uterine tube needs further investigation to understand the implications that the reproductive processes can have in the uterine tube. © 2014 Blackwell Verlag GmbH.

Ultrastructure of respiratory tract epithelium following irradiation or application of cytostatics

International Nuclear Information System (INIS)

Konradova, V.; Smelhaus, V.; Kanta, J.

1988-01-01

The ultrastructure was studied of the large bronchi epithelium in 3 patients with malignant tumors where signs of pulmonary fibrosis were found following irradiation and combined therapy. In 2 patients, pseudostratified cylindrical epithelium was observed with signs of pathological alteration, in the third patient an altered pseudostratified cylindrical epithelium with ultrastructural signs of commencing reconstructure into stratified squamous epithelium. The findings in the respiratory track epithelium of the patients were similar to those observed in a group of children with chronic or relapsing bronchitis and bronchopneumonia. The findings show marked disturbance of the ciliary border caused by reduction in the number of kinocilia which is associated with an impairment of the self-cleaning capacity of epithelium. (author). 1 tab., 10 refs

Developmental origin of the posterior pigmented epithelium of iris.

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Wang, Xiaobing; Xiong, Kai; Lu, Lei; Gu, Dandan; Wang, Songtao; Chen, Jing; Xiao, Honglei; Zhou, Guomin

2015-03-01

Iris epithelium is a double-layered pigmented cuboidal epithelium. According to the current model, the neural retina and the posterior iris pigment epithelium (IPE) are derived from the inner wall of the optic cup, while the retinal pigment epithelium (RPE) and the anterior IPE are derived from the outer wall of the optic cup during development. Our current study shows evidence, contradicting this model of fetal iris development. We demonstrate that human fetal iris expression patterns of Otx2 and Mitf transcription factors are similar, while the expressions of Otx2 and Sox2 are complementary. Furthermore, IPE and RPE exhibit identical morphologic development during the early embryonic period. Our results suggest that the outer layer of the optic cup forms two layers of the iris epithelium, and the posterior IPE is the inward-curling anterior rim of the outer layer of the optic cup. These findings provide a reasonable explanation of how IPE cells can be used as an appropriate substitute for RPE cells.

Deoxynivalenol affects in vitro intestinal epithelial cell barrier integrity through inhibition of protein synthesis

International Nuclear Information System (INIS)

Van De Walle, Jacqueline; Sergent, Therese; Piront, Neil; Toussaint, Olivier; Schneider, Yves-Jacques; Larondelle, Yvan

2010-01-01

Deoxynivalenol (DON), one of the most common mycotoxin contaminants of raw and processed cereal food, adversely affects the gastrointestinal tract. Since DON acts as a protein synthesis inhibitor, the constantly renewing intestinal epithelium could be particularly sensitive to DON. We analyzed the toxicological effects of DON on intestinal epithelial protein synthesis and barrier integrity. Differentiated Caco-2 cells, as a widely used model of the human intestinal barrier, were exposed to realistic intestinal concentrations of DON (50, 500 and 5000 ng/ml) during 24 h. DON caused a concentration-dependent decrease in total protein content associated with a reduction in the incorporation of [ 3 H]-leucine, demonstrating its inhibitory effect on protein synthesis. DON simultaneously increased the paracellular permeability of the monolayer as reflected through a decreased transepithelial electrical resistance associated with an increased paracellular flux of the tracer [ 3 H]-mannitol. A concentration-dependent reduction in the expression level of the tight junction constituent claudin-4 was demonstrated by Western blot, which was not due to diminished transcription, increased degradation, or NF-κB, ERK or JNK activation, and was also observed for a tight junction independent protein, i.e. intestinal alkaline phosphatase. These results demonstrate a dual toxicological effect of DON on differentiated Caco-2 cells consisting in an inhibition of protein synthesis as well as an increase in monolayer permeability, and moreover suggest a possible link between them through diminished synthesis of the tight junction constituent claudin-4.

Studies on the age-dependent proliferation kinetics of the epithelium of the rat small intestine

International Nuclear Information System (INIS)

Kranz, D.; Dietze, F.; Laue, R.; Fuhrmann, I.

1980-01-01

The small intestine of 244 Wistar rats, aged 6 days, 6 weeks, 6, 12, 23, and 28 months, respectively. were investigated autoradiographically as to their age-dependent cell proliferation kinetics of the mucosal epithelial cells. There were age-dependent differences concerning the hourly regeneration ratio of the crypt cells and the migration velocity of the enterocytes. Both parameters became greater while the existing non growth fraction became smaller with increasing age. The non growth fraction seems to be a reserve being involved into the proliferating pool if required

Epithelium percentage estimation facilitates epithelial quantitative protein measurement in tissue specimens.

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Chen, Jing; Toghi Eshghi, Shadi; Bova, George Steven; Li, Qing Kay; Li, Xingde; Zhang, Hui

2013-12-01

The rapid advancement of high-throughput tools for quantitative measurement of proteins has demonstrated the potential for the identification of proteins associated with cancer. However, the quantitative results on cancer tissue specimens are usually confounded by tissue heterogeneity, e.g. regions with cancer usually have significantly higher epithelium content yet lower stromal content. It is therefore necessary to develop a tool to facilitate the interpretation of the results of protein measurements in tissue specimens. Epithelial cell adhesion molecule (EpCAM) and cathepsin L (CTSL) are two epithelial proteins whose expressions in normal and tumorous prostate tissues were confirmed by measuring staining intensity with immunohistochemical staining (IHC). The expressions of these proteins were measured by ELISA in protein extracts from OCT embedded frozen prostate tissues. To eliminate the influence of tissue heterogeneity on epithelial protein quantification measured by ELISA, a color-based segmentation method was developed in-house for estimation of epithelium content using H&E histology slides from the same prostate tissues and the estimated epithelium percentage was used to normalize the ELISA results. The epithelium contents of the same slides were also estimated by a pathologist and used to normalize the ELISA results. The computer based results were compared with the pathologist's reading. We found that both EpCAM and CTSL levels, measured by ELISA assays itself, were greatly affected by epithelium content in the tissue specimens. Without adjusting for epithelium percentage, both EpCAM and CTSL levels appeared significantly higher in tumor tissues than normal tissues with a p value less than 0.001. However, after normalization by the epithelium percentage, ELISA measurements of both EpCAM and CTSL were in agreement with IHC staining results, showing a significant increase only in EpCAM with no difference in CTSL expression in cancer tissues. These results

Lipopolysaccharide Binding Protein Enables Intestinal Epithelial Restitution Despite Lipopolysaccharide Exposure

Science.gov (United States)

Richter, Juli M.; Schanbacher, Brandon L.; Huang, Hong; Xue, Jianjing; Bauer, John A.; Giannone, Peter J.

2011-01-01

Intestinal epithelial restitution is the first part in the process of mucosal repair after injury in the intestine. Integrity of the intestinal mucosal barrier is important as a first line of defense against bacteria and endotoxin. Necrotizing enterocolitis (NEC) is a major cause of morbidity and mortality in extremely low birth weight infants, but its mechanisms are not well defined. Abnormal bacterial colonization, immature barrier function, innate immunity activation and inflammation likely play a role. Lipopolysaccharide (LPS) binding protein (LBP) is secreted by enterocytes in response to inflammatory stimuli and has concentration-dependent effects. At basal concentrations, LBP stimulates the inflammatory response by presenting LPS to its receptor. However, at high concentrations, LBP is able to neutralize LPS and prevent an exaggerated inflammatory response. We sought to determine how LBP would affect wound healing in an in vitro model of intestinal cell restitution and protect against intestinal injury in a rodent model of NEC. Immature intestinal epithelial cells (IEC-6) were seeded in poly-l-lysine coated 8 chamber slides and grown to confluence. A 500μm wound was created using a cell scraper mounted on the microscope to achieve uniform wounding. Media was replaced with media containing LPS +/− LBP. Slide wells were imaged after 0, 8, and 24 hours and then fixed. Cellular restitution was evaluated via digital images captured on an inverted microscope and wound closure was determined by automated analysis. TLR4 was determined by rtPCR after RNA isolation from wounded cells 24 hours after treatment. LPS alone attenuated wound healing in immature intestinal epithelium. This attenuation is reversed by 24 hours with increasing concentrations of LBP so that wound healing is equivalent to control (p< 0.001). TLR4 was increased with LPS alone but levels returned to that of control after addition of LBP in the higher concentrations. LBP had no effect on the

The role of the Hes1 crosstalk hub in Notch-Wnt interactions of the intestinal crypt

KAUST Repository

Kay, Sophie K.

2017-03-01

The Notch pathway plays a vital role in determining whether cells in the intestinal epithelium adopt a secretory or an absorptive phenotype. Cell fate specification is coordinated via Notch’s interaction with the canonical Wnt pathway. Here, we propose a new mathematical model of the Notch and Wnt pathways, in which the Hes1 promoter acts as a hub for pathway crosstalk. Computational simulations of the model can assist in understanding how healthy intestinal tissue is maintained, and predict the likely consequences of biochemical knockouts upon cell fate selection processes. Chemical reaction network theory (CRNT) is a powerful, generalised framework which assesses the capacity of our model for monostability or multistability, by analysing properties of the underlying network structure without recourse to specific parameter values or functional forms for reaction rates. CRNT highlights the role of β-catenin in stabilising the Notch pathway and damping oscillations, demonstrating that Wnt-mediated actions on the Hes1 promoter can induce dynamic transitions in the Notch system, from multistability to monostability. Time-dependent model simulations of cell pairs reveal the stabilising influence of Wnt upon the Notch pathway, in which β-catenin- and Dsh-mediated action on the Hes1 promoter are key in shaping the subcellular dynamics. Where Notch-mediated transcription of Hes1 dominates, there is Notch oscillation and maintenance of fate flexibility; Wnt-mediated transcription of Hes1 favours bistability akin to cell fate selection. Cells could therefore regulate the proportion of Wnt- and Notch-mediated control of the Hes1 promoter to coordinate the timing of cell fate selection as they migrate through the intestinal epithelium and are subject to reduced Wnt stimuli. Furthermore, mutant cells characterised by hyperstimulation of the Wnt pathway may, through coupling with Notch, invert cell fate in neighbouring healthy cells, enabling an aberrant cell to maintain

The role of the Hes1 crosstalk hub in Notch-Wnt interactions of the intestinal crypt

KAUST Repository

Kay, Sophie K.; Harrington, Heather A.; Shepherd, Sarah; Brennan, Keith; Dale, Trevor; Osborne, James M.; Gavaghan, David J.; Byrne, Helen M.

2017-01-01

The Notch pathway plays a vital role in determining whether cells in the intestinal epithelium adopt a secretory or an absorptive phenotype. Cell fate specification is coordinated via Notch’s interaction with the canonical Wnt pathway. Here, we propose a new mathematical model of the Notch and Wnt pathways, in which the Hes1 promoter acts as a hub for pathway crosstalk. Computational simulations of the model can assist in understanding how healthy intestinal tissue is maintained, and predict the likely consequences of biochemical knockouts upon cell fate selection processes. Chemical reaction network theory (CRNT) is a powerful, generalised framework which assesses the capacity of our model for monostability or multistability, by analysing properties of the underlying network structure without recourse to specific parameter values or functional forms for reaction rates. CRNT highlights the role of β-catenin in stabilising the Notch pathway and damping oscillations, demonstrating that Wnt-mediated actions on the Hes1 promoter can induce dynamic transitions in the Notch system, from multistability to monostability. Time-dependent model simulations of cell pairs reveal the stabilising influence of Wnt upon the Notch pathway, in which β-catenin- and Dsh-mediated action on the Hes1 promoter are key in shaping the subcellular dynamics. Where Notch-mediated transcription of Hes1 dominates, there is Notch oscillation and maintenance of fate flexibility; Wnt-mediated transcription of Hes1 favours bistability akin to cell fate selection. Cells could therefore regulate the proportion of Wnt- and Notch-mediated control of the Hes1 promoter to coordinate the timing of cell fate selection as they migrate through the intestinal epithelium and are subject to reduced Wnt stimuli. Furthermore, mutant cells characterised by hyperstimulation of the Wnt pathway may, through coupling with Notch, invert cell fate in neighbouring healthy cells, enabling an aberrant cell to maintain

The role of the Hes1 crosstalk hub in Notch-Wnt interactions of the intestinal crypt.

Directory of Open Access Journals (Sweden)

Sophie K Kay

2017-02-01

Full Text Available The Notch pathway plays a vital role in determining whether cells in the intestinal epithelium adopt a secretory or an absorptive phenotype. Cell fate specification is coordinated via Notch's interaction with the canonical Wnt pathway. Here, we propose a new mathematical model of the Notch and Wnt pathways, in which the Hes1 promoter acts as a hub for pathway crosstalk. Computational simulations of the model can assist in understanding how healthy intestinal tissue is maintained, and predict the likely consequences of biochemical knockouts upon cell fate selection processes. Chemical reaction network theory (CRNT is a powerful, generalised framework which assesses the capacity of our model for monostability or multistability, by analysing properties of the underlying network structure without recourse to specific parameter values or functional forms for reaction rates. CRNT highlights the role of β-catenin in stabilising the Notch pathway and damping oscillations, demonstrating that Wnt-mediated actions on the Hes1 promoter can induce dynamic transitions in the Notch system, from multistability to monostability. Time-dependent model simulations of cell pairs reveal the stabilising influence of Wnt upon the Notch pathway, in which β-catenin- and Dsh-mediated action on the Hes1 promoter are key in shaping the subcellular dynamics. Where Notch-mediated transcription of Hes1 dominates, there is Notch oscillation and maintenance of fate flexibility; Wnt-mediated transcription of Hes1 favours bistability akin to cell fate selection. Cells could therefore regulate the proportion of Wnt- and Notch-mediated control of the Hes1 promoter to coordinate the timing of cell fate selection as they migrate through the intestinal epithelium and are subject to reduced Wnt stimuli. Furthermore, mutant cells characterised by hyperstimulation of the Wnt pathway may, through coupling with Notch, invert cell fate in neighbouring healthy cells, enabling an aberrant

Premalignant alterations of the gastric mucosa

International Nuclear Information System (INIS)

Frager, D.; Mitsudo, S.; Kozecky, O.; Frager, J.; Wolf, E.; Beneventano, T.C.

1986-01-01

Atrophic gastritus or intestinal metaplasia is the precursor to many gastric carcinomas that arise in a dysplatic epithelium. The authors retrospectively reviewed the radiographic features of the gastric mucosa in 30 patients with the pathologic diagnosis of intestinal metaplasia (27) or atrophic gastritus (3). In 12 patients (40%) the area gastricae were enlarged to 5 mm or greater. In these 12 patients and in an additional 11 (total of 23, or 76%), a polypoid-nodular gastric mucosal pattern was seen. These findings and patterns are illustrated, and the differential diagnosis and clinical implications are discussed

Effects of colchicine on the intestinal transport of endogenous lipid. Ultrastructural, biochemical, and radiochemical studies in fasting rats

International Nuclear Information System (INIS)

Pavelka, M.; Gangl, A.

1983-01-01

The involvement of microtubules in the transepithelial transport of exogenous lipid in intestinal absorptive cells has been suggested. Using electronmicroscopic, biochemical, and radiochemical methods, researchers have studied the effects of the antimicrotubular agent colchicine on the intestinal mucosa and on the intestinal transport of endogenous lipid of rats in the fasting state. After colchicine treatment, the concentration of triglycerides in intestinal mucosa of rats fasted for 24 h doubled, and electron microscopic studies showed a striking accumulation of lipid particles in absorptive epithelial cells of the tips of jejunal villi. These findings suggest that colchicine interferes with the intestinal transepithelial transport of endogenous lipoproteins. Additional studies, using an intraduodenal pulse injection of [ 14 C]linoleic acid, showed that colchicine does not affect the uptake of fatty acids by intestinal mucosa. However, it had divergent effects on fatty acid esterification, enhancing their incorporation into triglycerides relative to phospholipids, and caused a significant accumulation of endogenous diglycerides, triglycerides, and cholesterol esters within the absorptive intestinal epithelium. Detailed ultrastructural and morphometric studies revealed a decrease of visible microtubules, and a displacement of the smooth and rough endoplasmic reticulum and Golgi apparatus. Furthermore, it is shown that after colchicine treatment, microvilli appear at the lateral plasma membrane of intestinal absorptive cells, a change not previously reported to our knowledge. Thus, our study shows that colchicine causes significant changes in enterocyte ultrastructure and colchicine perturbs the reesterification of absorbed endogenous fatty acids and their secretion in the form of triglyceride-rich lipoproteins from the enterocyte

Comparison of Mouse and Human Retinal Pigment Epithelium Gene Expression Profiles: Potential Implications for Age-Related Macular Degeneration

NARCIS (Netherlands)

Bennis, A.; Gorgels, T.G.M.F.; ten Brink, J.B.; van der Spek, P.J.; Bossers, K.; Heine, V.M.; Bergen, A.A.

2015-01-01

Background The human retinal pigment epithelium (RPE) plays an important role in the pathogenesis of age related macular degeneration (AMD). AMD is the leading cause of blindness worldwide. There is currently no effective treatment available. Preclinical studies in AMD mouse models are essential to

Comparison of Mouse and Human Retinal Pigment Epithelium Gene Expression Profiles : Potential Implications for Age-Related Macular Degeneration

NARCIS (Netherlands)

Bennis, Anna; Gorgels, Theo G M F; Ten Brink, Jacoline B; van der Spek, Peter J; Bossers, Koen; Heine, Vivi M; Bergen, Arthur A

2015-01-01

BACKGROUND: The human retinal pigment epithelium (RPE) plays an important role in the pathogenesis of age related macular degeneration (AMD). AMD is the leading cause of blindness worldwide. There is currently no effective treatment available. Preclinical studies in AMD mouse models are essential to

Comparison of Mouse and Human Retinal Pigment Epithelium Gene Expression Profiles: Potential Implications for Age-Related Macular Degeneration

NARCIS (Netherlands)

Bennis, Anna; Gorgels, Theo G. M. F.; ten Brink, Jacoline B.; van der Spek, Peter J.; Bossers, Koen; Heine, Vivi M.; Bergen, Arthur A.

2015-01-01

The human retinal pigment epithelium (RPE) plays an important role in the pathogenesis of age related macular degeneration (AMD). AMD is the leading cause of blindness worldwide. There is currently no effective treatment available. Preclinical studies in AMD mouse models are essential to develop new

Polyphenol-Rich Propolis Extracts Strengthen Intestinal Barrier Function by Activating AMPK and ERK Signaling

Directory of Open Access Journals (Sweden)

Kai Wang

2016-05-01

Full Text Available Propolis has abundant polyphenolic constituents and is used widely as a health/functional food. Here, we investigated the effects of polyphenol-rich propolis extracts (PPE on intestinal barrier function in human intestinal epithelial Caco-2 cells, as well as in rats. In Caco-2 cells, PPE increased transepithelial electrical resistance and decreased lucifer yellow flux. PPE-treated cells showed increased expression of the tight junction (TJ loci occludin and zona occludens (ZO-1. Confocal microscopy showed organized expressions in proteins related to TJ assembly, i.e., occludin and ZO-1, in response to PPE. Furthermore, PPE led to the activation of AMPK, ERK1/2, p38, and Akt. Using selective inhibitors, we found that the positive effects of PPE on barrier function were abolished in cells in which AMPK and ERK1/2 signaling were inhibited. Moreover, rats fed a diet supplemented with PPE (0.3% in the diet exhibited increased colonic epithelium ZO-1 expression. Overall, these data suggest that PPE strengthens intestinal barrier function by activating AMPK and ERK signaling and provide novel insights into the potential application of propolis for human gut health.

The epithelium in idiopathic pulmonary fibrosis: breaking the barrier

Directory of Open Access Journals (Sweden)

Ana eCamelo

2014-01-01

Full Text Available Idiopathic pulmonary fibrosis is a progressive disease of unknown etiology characterised by a dysregulated wound healing response that leads to fatal accumulation of fibroblasts and extracellular matrix in the lung, which compromises tissue architecture and lung function capacity. Injury to type II alveolar epithelial cells is thought to be the key event for the initiation of the disease, and so far both genetic factors, such as mutations in telomerase and MUC5b genes as well as environmental components, like cigarette smoking, exposure to asbestos and viral infections have been implicated as potential initiating triggers. The injured epithelium then enters a state of senescence-associated secretory phenotype whereby it produces both pro-inflammatory and pro-fibrotic factors that contribute to the wound healing process in the lung. Immune cells, like macrophages and neutrophils as well as activated myofibroblasts then perpetuate this cascade of epithelial cell apoptosis and proliferation by release of pro-fibrotic TGF-β and continuous deposition of extracellular matrix stiffens the basement membrane, altogether having a deleterious impact on epithelial cell function. In this review we describe the role of the epithelium as both a physical and immunological barrier between environment and self in the homeostatic versus diseased lung and explore the potential mechanisms of epithelial cell injury and the impact of loss of epithelial cell permeability and function on cytokine production, inflammation and myofibroblast activation in the fibrotic lung.

Intestinal exposure to PCB 153 induces inflammation via the ATM/NEMO pathway.

Science.gov (United States)

Phillips, Matthew C; Dheer, Rishu; Santaolalla, Rebeca; Davies, Julie M; Burgueño, Juan; Lang, Jessica K; Toborek, Michal; Abreu, Maria T

2018-01-15

Polychlorinated biphenyls (PCBs) are persistent organic pollutants that adversely affect human health. PCBs bio-accumulate in organisms important for human consumption. PCBs accumulation in the body leads to activation of the transcription factor NF-κB, a major driver of inflammation. Despite dietary exposure being one of the main routes of exposure to PCBs, the gut has been widely ignored when studying the effects of PCBs. We investigated the effects of PCB 153 on the intestine and addressed whether PCB 153 affected intestinal permeability or inflammation and the mechanism by which this occurred. Mice were orally exposed to PCB 153 and gut permeability was assessed. Intestinal epithelial cells (IECs) were collected and evaluated for evidence of genotoxicity and inflammation. A human IEC line (SW480) was used to examine the direct effects of PCB 153 on epithelial function. NF-кB activation was measured using a reporter assay, DNA damage was assessed, and cytokine expression was ascertained with real-time PCR. Mice orally exposed to PCB 153 had an increase in intestinal permeability and inflammatory cytokine expression in their IECs; inhibition of NF-кB ameliorated both these effects. This inflammation was associated with genotoxic damage and NF-кB activation. Exposure of SW480 cells to PCB 153 led to similar effects as seen in vivo. We found that activation of the ATM/NEMO pathway by genotoxic stress was upstream of NF-kB activation. These results demonstrate that oral exposure to PCB 153 is genotoxic to IECs and induces downstream inflammation and barrier dysfunction in the intestinal epithelium. Copyright © 2017 Elsevier Inc. All rights reserved.

Cdx2 modulates proliferation in normal human intestinal epithelial crypt cells

International Nuclear Information System (INIS)

Escaffit, Fabrice; Pare, Frederic; Gauthier, Remy; Rivard, Nathalie; Boudreau, Francois; Beaulieu, Jean-Francois

2006-01-01

The homeobox gene Cdx2 is involved in the regulation of the expression of intestine specific markers such as sucrase-isomaltase and lactase-phlorizin hydrolase. Previous studies performed with immortalized or transformed intestinal cell lines have provided evidence that Cdx2 can promote morphological and functional differentiation in these experimental models. However, no data exist concerning the implication of this factor in normal human intestinal cell physiology. In the present work, we have investigated the role of Cdx2 in normal human intestinal epithelial crypt (HIEC) cells that lack this transcription factor. The establishment of HIEC cells expressing Cdx2 in an inducible manner shows that forced expression of Cdx2 significantly alters the proliferation of intestinal crypt cells and stimulates dipeptidylpeptidase IV expression but is not sufficient to trigger intestinal terminal differentiation. These observations suggest that Cdx2 requires additional factors to activate the enterocyte differentiation program in normal undifferentiated cells

FcγRI (CD64): an identity card for intestinal macrophages.

Science.gov (United States)

De Calisto, Jaime; Villablanca, Eduardo J; Mora, J Rodrigo

2012-12-01

Macrophages are becoming increasingly recognized as key cellular players in intestinal immune homeostasis. However, differentiating between macrophages and dendritic cells (DCs) is often difficult, and finding a specific phenotypic signature for intestinal macrophage identification has remained elusive. In this issue of the European Journal of Immunology, Tamoutounour et al. [Eur. J. Immunol. 2012. 42: 3150-3166] identify CD64 as a specific macrophage marker that can be used to discriminate DCs from macrophages in the murine small and large intestine, under both steady-state and inflammatory conditions. The authors also propose a sequential 'monocyte-waterfall' model for intestinal macrophage differentiation, with implications for immune tolerance and inflammation at the gut mucosal interface. This Commentary will discuss the advantages and potential limitations of CD64 as a marker for intestinal macrophages. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Prostaglandin E2 release from dermis regulates sodium permeability of frog skin epithelium

DEFF Research Database (Denmark)

Rytved, Klaus A.; Brodin, Birger; Nielsen, Robert

1995-01-01

Arachidonic acid, cAMP, epithelium, frog skin, intracellular calcium, prostaglandin E*U2, sodium transport, tight epithelium.......Arachidonic acid, cAMP, epithelium, frog skin, intracellular calcium, prostaglandin E*U2, sodium transport, tight epithelium....

Expression pattern of adhesion molecules in junctional epithelium differs from that in other gingival epithelia.

Science.gov (United States)

Hatakeyama, S; Yaegashi, T; Oikawa, Y; Fujiwara, H; Mikami, T; Takeda, Y; Satoh, M

2006-08-01

The gingival epithelium is the physiologically important interface between the bacterially colonized gingival sulcus and periodontal soft and mineralized connective tissues, requiring protection from exposure to bacteria and their products. However, of the three epithelia comprising the gingival epithelium, the junctional epithelium has much wider intercellular spaces than the sulcular epithelium and oral gingival epithelium. Hence, the aim of the present study was to characterize the cell adhesion structure in the junctional epithelium compared with the other two epithelia. Gingival epithelia excised at therapeutic flap surgery from patients with periodontitis were examined for expression of adhesion molecules by immunofluorescence. In the oral gingival epithelium and sulcular epithelium, but not in the junctional epithelium, desmoglein 1 and 2 in cell-cell contact sites were more abundant in the upper than the suprabasal layers. E-cadherin, the main transmembranous molecule of adherens junctions, was present in spinous layers of the oral gingival epithelium and sulcular epithelium, but was scarce in the junctional epithelium. In contrast, desmoglein 3 and P-cadherin were present in all layers of the junctional epithelium as well as the oral gingival epithelium and sulcular epithelium. Connexin 43 was clearly localized to spinous layers of the oral gingival epithelium, sulcular epithelium and parts of the junctional epithelium. Claudin-1 and occludin were expressed in the cell membranes of a few superficial layers of the oral gingival epithelium. These findings indicated that the junctional epithelium contains only a few desmosomes, composed of only desmoglein 3; adherens junctions are probably absent because of defective E-cadherin. Thus, the anchoring junctions connecting junctional epithelium cells are lax, causing widened intercellular spaces. In contrast, the oral gingival epithelium, which has a few tight junctions, functions as a barrier.

Probiotic-derived polyphosphate enhances the epithelial barrier function and maintains intestinal homeostasis through integrin-p38 MAPK pathway.

Directory of Open Access Journals (Sweden)

Shuichi Segawa

Full Text Available Probiotics exhibit beneficial effects on human health, particularly in the maintenance of intestinal homeostasis in a complex manner notwithstanding the diversity of an intestinal flora between individuals. Thus, it is highly probable that some common molecules secreted by probiotic and/or commensal bacteria contribute to the maintenance of intestinal homeostasis and protect the intestinal epithelium from injurious stimuli. To address this question, we aimed to isolate the cytoprotective compound from a lactobacillus strain, Lactobacillus brevis SBC8803 which possess the ability to induce cytoprotective heat shock proteins in mouse small intestine. L. brevis was incubated in MRS broth and the supernatant was passed through with a 0.2-µm filter. Caco2/bbe cells were treated with the culture supernatant, and HSP27 expression was evaluated by Western blotting. HSP27-inducible components were separated by ammonium sulfate precipitation, DEAE anion exchange chromatography, gel filtration, and HPLC. Finally, we identified that the HSP27-inducible fraction was polyphosphate (poly P, a simple repeated structure of phosphates, which is a common product of lactobacilli and other bacteria associated with intestinal microflora without any definitive physiological functions. Then, poly P was synthesized by poly P-synthesizing enzyme polyphosphate kinase. The synthesized poly P significantly induced HSP27 from Caco2/BBE cells. In addition, Poly P suppressed the oxidant-induced intestinal permeability in the mouse small intestine and pharmacological inhibitors of p38 MAPK and integrins counteract its protective effect. Daily intrarectal administration of poly P (10 µg improved the inflammation grade and survival rate in 4% sodium dextran sulfate-administered mice. This study, for the first time, demonstrated that poly P is the molecule responsible for maintaining intestinal barrier actions which are mediated through the intestinal integrin β1-p38 MAPK.

16,16-dimethyl prostaglandin E2 increases survival of murine intestinal stem cells when given before photon radiation

International Nuclear Information System (INIS)

Hanson, W.R.; Thomas, C.

1983-01-01

A variety of prostaglandins (PG) protect the gastric and intestinal mucosa when given before damaging agents as absolute ethanol, acidified taurocholate, boiling water, or nonsteroidal anti-inflammatory agents (NSAI). A synthetic prostaglandin, 16,16-dimethyl PGE 2 , shown to be cytoprotective at physiologic levels to the above agents was given to mice 1 h before or 15 min after 137 Cs gamma(γ) whole-body irradiation. The survival of intestinal stem cells measured by their ability to form in situ colonies of regenerating epithelium was increased stem cells measured by their ability to form in situ colonies of regenerating epithelium was increased when 16,16-dimethyl PGE 2 was given before but not after 137 Cs γ irradiation. The maximum degree of 16,16-dimethyl PGE 2 -induced radioprotection was seen when the drug was given 1 h before irradiation. No radioprotection was seen when the interval between drug and irradiation was 3 h or longer. When the time between 16,16-dimethyl PGE 2 and irradiation was kept at 1 h, the degree of radioprotection was dependent on the PG drug dose. There was a steep rise in the number of surviving cells at low doses of PG. These results imply that tumors which secrete PGE 2 may in part be protected from the lethal effects of ionizing photon radiation

Circadian rhythm disruption impairs tissue homeostasis and exacerbates chronic inflammation in the intestine.

Science.gov (United States)

Pagel, René; Bär, Florian; Schröder, Torsten; Sünderhauf, Annika; Künstner, Axel; Ibrahim, Saleh M; Autenrieth, Stella E; Kalies, Kathrin; König, Peter; Tsang, Anthony H; Bettenworth, Dominik; Divanovic, Senad; Lehnert, Hendrik; Fellermann, Klaus; Oster, Henrik; Derer, Stefanie; Sina, Christian

2017-11-01

Endogenous circadian clocks regulate 24-h rhythms of physiology and behavior. Circadian rhythm disruption (CRD) is suggested as a risk factor for inflammatory bowel disease. However, the underlying molecular mechanisms remain unknown. Intestinal biopsies from Per1/2 mutant and wild-type (WT) mice were investigated by electron microscopy, immunohistochemistry, and bromodeoxyuridine pulse-chase experiments. TNF-α was injected intraperitoneally, with or without necrostatin-1, into Per1/2 mice or rhythmic and externally desynchronized WT mice to study intestinal epithelial cell death. Experimental chronic colitis was induced by oral administration of dextran sodium sulfate. In vitro , caspase activity was assayed in Per1/2-specific small interfering RNA-transfected cells. Wee1 was overexpressed to study antiapoptosis and the cell cycle. Genetic ablation of circadian clock function or environmental CRD in mice increased susceptibility to severe intestinal inflammation and epithelial dysregulation, accompanied by excessive necroptotic cell death and a reduced number of secretory epithelial cells. Receptor-interacting serine/threonine-protein kinase (RIP)-3-mediated intestinal necroptosis was linked to increased mitotic cell cycle arrest via Per1/2-controlled Wee1, resulting in increased antiapoptosis via cellular inhibitor of apoptosis-2. Together, our data suggest that circadian rhythm stability is pivotal for the maintenance of mucosal barrier function. CRD increases intestinal necroptosis, thus rendering the gut epithelium more susceptible to inflammatory processes.-Pagel, R., Bär, F., Schröder, T., Sünderhauf, A., Künstner, A., Ibrahim, S. M., Autenrieth, S. E., Kalies, K., König, P., Tsang, A. H., Bettenworth, D., Divanovic, S., Lehnert, H., Fellermann, K., Oster, H., Derer, S., Sina, C. Circadian rhythm disruption impairs tissue homeostasis and exacerbates chronic inflammation in the intestine. © FASEB.

Circadian disorganization alters intestinal microbiota.

Directory of Open Access Journals (Sweden)

Robin M Voigt

Full Text Available Intestinal dysbiosis and circadian rhythm disruption are associated with similar diseases including obesity, metabolic syndrome, and inflammatory bowel disease. Despite the overlap, the potential relationship between circadian disorganization and dysbiosis is unknown; thus, in the present study, a model of chronic circadian disruption was used to determine the impact on the intestinal microbiome. Male C57BL/6J mice underwent once weekly phase reversals of the light:dark cycle (i.e., circadian rhythm disrupted mice to determine the impact of circadian rhythm disruption on the intestinal microbiome and were fed either standard chow or a high-fat, high-sugar diet to determine how diet influences circadian disruption-induced effects on the microbiome. Weekly phase reversals of the light:dark (LD cycle did not alter the microbiome in mice fed standard chow; however, mice fed a high-fat, high-sugar diet in conjunction with phase shifts in the light:dark cycle had significantly altered microbiota. While it is yet to be established if some of the adverse effects associated with circadian disorganization in humans (e.g., shift workers, travelers moving across time zones, and in individuals with social jet lag are mediated by dysbiosis, the current study demonstrates that circadian disorganization can impact the intestinal microbiota which may have implications for inflammatory diseases.

Quantitative rather than qualitative differences in gene expression predominate in intestinal cell maturation along distinct cell lineages

International Nuclear Information System (INIS)

Velcich, Anna; Corner, Georgia; Paul, Doru; Zhuang Min; Mariadason, John M.; Laboisse, Christian; Augenlicht, Leonard

2005-01-01

Several cell types are present in the intestinal epithelium that likely arise from a common precursor, the stem cell, and each mature cell type expresses a unique set of genes that characterizes its functional phenotype. Although the process of differentiation is intimately linked to the cessation of proliferation, the mechanisms that dictate intestinal cell fate determination are not well characterized. To investigate the reprogramming of gene expression during the cell lineage allocation/differentiation process, we took advantage of a unique system of two clonal derivatives of HT29 cells, Cl16E and Cl19A cells, which spontaneously differentiate as mucus producing goblet and chloride-secreting cells, respectively, as a function of time. By profiling gene expression, we found that these two cell lines show remarkably similar kinetics of change in gene expression and common clusters of coordinately regulated genes. This demonstrates that lineage-specific differentiation of intestinal epithelial cells is characterized overall by the sequential recruitment of functionally similar gene sets independent of the final phenotype of the mature cells

Clathrin-mediated endocytosis and transcytosis of enterotoxigenic Escherichia coli F4 fimbriae in porcine intestinal epithelial cells.

Science.gov (United States)

Rasschaert, Kristien; Devriendt, Bert; Favoreel, Herman; Goddeeris, Bruno M; Cox, Eric

2010-10-15

Enterotoxigenic Escherichia coli (ETEC) cause severe diarrhea in neonatal and recently weaned piglets. Previously, we demonstrated that oral immunization of F4 receptor positive piglets with purified F4 fimbriae induces a protective F4-specific intestinal immune response. However, in F4 receptor negative animals no F4-specific immune response can be elicited, indicating that the induction of an F4-specific mucosal immune response upon oral immunisation is receptor-dependent. Although F4 fimbriae undergo transcytosis across the intestinal epithelium in vivo, the endocytosis pathways used remain unknown. In the present study, we characterized the internalization of F4 fimbriae in the porcine intestinal epithelial cell line IPEC-J2. The results in the present study demonstrate that F4 fimbriae are internalized through a clathrin-dependent pathway. Furthermore, our results suggest that F4 fimbriae are transcytosed across differentiated IPEC-J2 cells. This receptor-dependent transcytosis of F4 fimbriae may explain the immunogenicity of these fimbriae upon oral administration in vivo. (c) 2010 Elsevier B.V. All rights reserved.

Coelomic epithelium-derived cells in visceral morphogenesis.

Science.gov (United States)

Ariza, Laura; Carmona, Rita; Cañete, Ana; Cano, Elena; Muñoz-Chápuli, Ramón

2016-03-01

Coelomic cavities of vertebrates are lined by a mesothelium which develops from the lateral plate mesoderm. During development, the coelomic epithelium is a highly active cell layer, which locally is able to supply mesenchymal cells that contribute to the mesodermal elements of many organs and provide signals which are necessary for their development. The relevance of this process of mesenchymal cell supply to the developing organs is becoming clearer because genetic lineage tracing techniques have been developed in recent years. Body wall, heart, liver, lungs, gonads, and gastrointestinal tract are populated by cells derived from the coelomic epithelium which contribute to their connective and vascular tissues, and sometimes to specialized cell types such as the stellate cells of the liver, the Cajal interstitial cells of the gut or the Sertoli cells of the testicle. In this review we collect information about the contribution of coelomic epithelium derived cells to visceral development, their developmental fates and signaling functions. The common features displayed by all these processes suggest that the epithelial-mesenchymal transition of the embryonic coelomic epithelium is an underestimated but key event of vertebrate development, and probably it is shared by all the coelomate metazoans. © 2015 Wiley Periodicals, Inc.

In vitro characterization of cadmium and zinc uptake via the gastro-intestinal tract of the rainbow trout (Oncorhynchus mykiss): Interactive effects and the influence of calcium

International Nuclear Information System (INIS)

Ojo, Adeola A.; Wood, Chris M.

2008-01-01

An in vitro gut sac technique was employed to study whether Cd and Zn uptake mechanisms in the gastro-intestinal tract of the rainbow trout are similar to those at the gills, where both metals are taken up via the Ca transport pathway. Metal accumulation in surface mucus, in the mucosal epithelium, and transport into the blood space were assayed using radiolabelled Cd or Zn concentrations of 50 μmol L -1 in the luminal (internal) saline. Elevated luminal Ca (10 or 100 mmol L -1 versus 1 mmol L -1 ) reduced Cd uptake into all three phases by approximately 60% in the stomach, but had no effect in the anterior, mid, or posterior intestine. This finding is in accordance with recent in vivo evidence that Ca is taken up mainly via the stomach, and that high [Ca] diets inhibit Cd accumulation from the food specifically in this section of the tract. In contrast, 10 mmol L -1 luminal Ca had no effect on Zn transport in any section, whereas 100 mmol L -1 Ca stimulated Zn uptake, by approximately threefold, into all three phases in the stomach only. There was no influence of elevated luminal Zn (10 mmol L -1 ) on Cd uptake in the stomach or anterior intestine, or of high Cd (10 mmol L -1 ) on Zn uptake in these sections. However, high [Zn] stimulated Cd transport into the blood space but inhibited accumulation in the mucosal epithelium and/or mucus-binding in the mid and posterior intestine, whereas high [Cd] exerted a reciprocal effect in the mid-intestine only. We conclude that Cd uptake occurs via an important Ca-sensitive mechanism in the stomach which is different from that at the gills, while Cd transport mechanisms in the intestine are not directly Ca-sensitive. Zn uptake does not appear to involve Ca uptake pathways, in contrast to the gills. These results are discussed in the context of other possible Cd and Zn transport pathways, and the emerging role of the stomach as an organ of divalent metal uptake

Oral epithelial stem cells – implications in normal development and cancer metastasis

Science.gov (United States)

Papagerakis, Silvana; Pannone, Giuseppe; Zheng, Li; About, Imad; Taqi, Nawar; Nguyen, Nghia P.T.; Matossian, Margarite; McAlpin, Blake; Santoro, Angela; McHugh, Jonathan; Prince, Mark E.; Papagerakis, Petros

2014-01-01

Oral mucosa is continuously exposed to environmental forces and has to be constantly renewed. Accordingly, the oral mucosa epithelium contains a large reservoir of epithelial stem cells necessary for tissue homeostasis. Despite considerable scientific advances in stem cell behavior in a number of tissues, fewer studies have been devoted to the stem cells in the oral epithelium. Most of oral mucosa stem cells studies are focused on identifying cancer stem cells (CSC) in oral squamous cell carcinomas (OSCCs) among other head and neck cancers. OSCCs are the most prevalent epithelial tumors of the head and neck region, marked by their aggressiveness and invasiveness. Due to their highly tumorigenic properties, it has been suggested that CSC may be the critical population of cancer cells in the development of OSCC metastasis. This review presents a brief overview of epithelium stem cells with implications in oral health, and the clinical implications of the CSC concept in OSCC metastatic dissemination. PMID:24803391

Triterpenoid herbal saponins enhance beneficial bacteria, decrease sulfate-reducing bacteria, modulate inflammatory intestinal microenvironment and exert cancer preventive effects in ApcMin/+ mice

Science.gov (United States)

Chen, Lei; Brar, Manreetpal S.; Leung, Frederick C. C.; Hsiao, W. L. Wendy

2016-01-01

Saponins derived from medicinal plants have raised considerable interest for their preventive roles in various diseases. Here, we investigated the impacts of triterpenoid saponins isolated from Gynostemma pentaphyllum (GpS) on gut microbiome, mucosal environment, and the preventive effect on tumor growth. Six-week old ApcMin/+ mice and their wild-type littermates were fed either with vehicle or GpS daily for the duration of 8 weeks. The fecal microbiome was analyzed by enterobacterial repetitive intergenic consensus (ERIC)-PCR and 16S rRNA gene pyrosequencing. Study showed that GpS treatment significantly reduced the number of intestinal polyps in a preventive mode. More importantly, GpS feeding strikingly reduced the sulfate-reducing bacteria lineage, which are known to produce hydrogen sulfide and contribute to damage the intestinal epithelium or even promote cancer progression. Meanwhile, GpS also boosted the beneficial microbes. In the gut barrier of the ApcMin/+ mice, GpS treatment increased Paneth and goblet cells, up-regulated E-cadherin and down-regulated N-cadherin. In addition, GpS decreased the pro-oncogenic β-catenin, p-Src and the p-STAT3. Furthermore, GpS might also improve the inflamed gut epithelium of the ApcMin/+ mice by upregulating the anti-inflammatory cytokine IL-4, while downregulating pro-inflammatory cytokines TNF-β, IL-1β and IL-18. Intriguingly, GpS markedly stimulated M2 and suppressed M1 macrophage markers, indicating that GpS altered mucosal cytokine profile in favor of the M1 to M2 macrophages switching, facilitating intestinal tissue repair. In conclusion, GpS might reverse the host's inflammatory phenotype by increasing beneficial bacteria, decreasing sulfate-reducing bacteria, and alleviating intestinal inflammatory gut environment, which might contribute to its cancer preventive effects. PMID:27121311

Effect Of Hydrolyzed Milk On The Adhesion Of Lactobacilli To Intestinal Cells*

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Volštátová T.

2015-03-01

Full Text Available Milk is an essential part of the human diet and is undoubtedly a major calcium source in human nutrition, accepted well by most individuals. Knowledge on how the components from dairy products support or reduce the adherence of probiotics to the intestinal epithelium is limited. The purpose of this study was to investigate the effect of acid-hydrolyzed milk on the adhesion ability of two potentially probiotic strains (Lactobacillus plantarum S2, Lactobacillus gasseri R to in vitro human intestinal epithelial model consisting of Caco-2 and mucus-secreting HT29-MTX co-culture. The adhesion of our tested strains L. gasseri and L. plantarum was 4.74 and 7.16%, respectively, when using inoculum of 2 × 108 CFU ml–1. Addition of acid-hydrolyzed milk to co-culture decreased the adherence by 53.7% for L. gasseri R and by 62.2% for L. plantarum S2. The results of this study evidently indicate the potential importance of the food matrix as a factor influencing probiotic colonization of the gut.

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Lentiviral-Mediated Transgene Expression Can Potentiate Intestinal Mesenchymal-Epithelial Signaling

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Kohn Aimee

2009-01-01

Full Text Available Abstract Mesenchymal-epithelial signaling is essential for the development of many organs and is often disrupted in disease. In this study, we demonstrate the use of lentiviral-mediated transgene delivery as an effective approach for ectopic transgene expression and an alternative to generation of transgenic animals. One benefit to this approach is that it can be used independently or in conjunction with established transgenic or knockout animals for studying modulation of mesenchymal-epithelial interactions. To display the power of this approach, we explored ectopic expression of a Wnt ligand in the mouse intestinal mesenchyme and demonstrate its functional influence on the adjacent epithelium. Our findings highlight the efficient use of lentiviral-mediated transgene expression for modulating mesenchymal-epithelial interactions in vivo.

Lentiviral-Mediated Transgene Expression Can Potentiate Intestinal Mesenchymal-Epithelial Signaling

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Dismuke Adria D

2009-07-01

Full Text Available Abstract Mesenchymal-epithelial signaling is essential for the development of many organs and is often disrupted in disease. In this study, we demonstrate the use of lentiviral-mediated transgene delivery as an effective approach for ectopic transgene expression and an alternative to generation of transgenic animals. One benefit to this approach is that it can be used independently or in conjunction with established transgenic or knockout animals for studying modulation of mesenchymal-epithelial interactions. To display the power of this approach, we explored ectopic expression of a Wnt ligand in the mouse intestinal mesenchyme and demonstrate its functional influence on the adjacent epithelium. Our findings highlight the efficient use of lentiviral-mediated transgene expression for modulating mesenchymal-epithelial interactions in vivo.

A paradox of transcriptional and functional innate interferon responses of human intestinal enteroids to enteric virus infection

Science.gov (United States)

Saxena, Kapil; Simon, Lukas M.; Zeng, Xi-Lei; Blutt, Sarah E.; Crawford, Sue E.; Sastri, Narayan P.; Karandikar, Umesh C.; Ajami, Nadim J.; Zachos, Nicholas C.; Kovbasnjuk, Olga; Donowitz, Mark; Conner, Margaret E.; Shaw, Chad A.; Estes, Mary K.

2017-01-01

The intestinal epithelium can limit enteric pathogens by producing antiviral cytokines, such as IFNs. Type I IFN (IFN-α/β) and type III IFN (IFN-λ) function at the epithelial level, and their respective efficacies depend on the specific pathogen and site of infection. However, the roles of type I and type III IFN in restricting human enteric viruses are poorly characterized as a result of the difficulties in cultivating these viruses in vitro and directly obtaining control and infected small intestinal human tissue. We infected nontransformed human intestinal enteroid cultures from multiple individuals with human rotavirus (HRV) and assessed the host epithelial response by using RNA-sequencing and functional assays. The dominant transcriptional pathway induced by HRV infection is a type III IFN-regulated response. Early after HRV infection, low levels of type III IFN protein activate IFN-stimulated genes. However, this endogenous response does not restrict HRV replication because replication-competent HRV antagonizes the type III IFN response at pre- and posttranscriptional levels. In contrast, exogenous IFN treatment restricts HRV replication, with type I IFN being more potent than type III IFN, suggesting that extraepithelial sources of type I IFN may be the critical IFN for limiting enteric virus replication in the human intestine. PMID:28069942

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Identification of multi-drug resistant Pseudomonas aeruginosa clinical isolates that are highly disruptive to the intestinal epithelial barrier

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Shevchenko Olga

2006-06-01

Full Text Available Abstract Background Multi-drug resistant Pseudomonas aeruginosa nosocomial infections are increasingly recognized worldwide. In this study, we focused on the virulence of multi-drug resistant clinical strains P. aeruginosa against the intestinal epithelial barrier, since P. aeruginosa can cause lethal sepsis from within the intestinal tract of critically ill and immuno-compromised patients via mechanisms involving disruption of epithelial barrier function. Methods We screened consecutively isolated multi-drug resistant P. aeruginosa clinical strains for their ability to disrupt the integrity of human cultured intestinal epithelial cells (Caco-2 and correlated these finding to related virulence phenotypes such as adhesiveness, motility, biofilm formation, and cytotoxicity. Results Results demonstrated that the majority of the multi-drug resistant P. aeruginosa clinical strains were attenuated in their ability to disrupt the barrier function of cultured intestinal epithelial cells. Three distinct genotypes were found that displayed an extreme epithelial barrier-disrupting phenotype. These strains were characterized and found to harbor the exoU gene and to display high swimming motility and adhesiveness. Conclusion These data suggest that detailed phenotypic analysis of the behavior of multi-drug resistant P. aeruginosa against the intestinal epithelium has the potential to identify strains most likely to place patients at risk for lethal gut-derived sepsis. Surveillance of colonizing strains of P. aeruginosa in critically ill patients beyond antibiotic sensitivity is warranted.

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16,16-dimethyl prostaglandin E/sub 2/ increases survival of murine intestinal stem cells when given before photon radiation

Energy Technology Data Exchange (ETDEWEB)

Hanson, W.R.; Thomas, C.

1983-11-01

A variety of prostaglandins (PG) protect the gastric and intestinal mucosa when given before damaging agents as absolute ethanol, acidified taurocholate, boiling water, or nonsteroidal anti-inflammatory agents (NSAI). A synthetic prostaglandin, 16,16-dimethyl PGE/sub 2/, shown to be cytoprotective at physiologic levels to the above agents was given to mice 1 h before or 15 min after /sup 137/Cs gamma(..gamma..) whole-body irradiation. The survival of intestinal stem cells measured by their ability to form in situ colonies of regenerating epithelium was increased stem cells measured by their ability to form in situ colonies of regenerating epithelium was increased when 16,16-dimethyl PGE/sub 2/ was given before but not after /sup 137/Cs ..gamma.. irradiation. The maximum degree of 16,16-dimethyl PGE/sub 2/-induced radioprotection was seen when the drug was given 1 h before irradiation. No radioprotection was seen when the interval between drug and irradiation was 3 h or longer. When the time between 16,16-dimethyl PGE/sub 2/ and irradiation was kept at 1 h, the degree of radioprotection was dependent on the PG drug dose. There was a steep rise in the number of surviving cells at low doses of PG. These results imply that tumors which secrete PGE/sub 2/ may in part be protected from the lethal effects of ionizing photon radiation.

Pathophysiology of increased intestinal permeability in obstructive jaundice

Science.gov (United States)

Assimakopoulos, Stelios F; Scopa, Chrisoula D; Vagianos, Constantine E

2007-01-01

Despite advances in preoperative evaluation and postoperative care, intervention, especially surgery, for relief of obstructive jaundice still carries high morbidity and mortality rates, mainly due to sepsis and renal dysfunction. The key event in the pathophysiology of obstructive jaundice-associated complications is endotoxemia of gut origin because of intestinal barrier failure. This breakage of the gut barrier in obstructive jaundice is multi-factorial, involving disruption of the immunologic, biological and mechanical barrier. Experimental and clinical studies have shown that obstructive jaundice results in increased intestinal permeability. The mechanisms implicated in this phenomenon remain unresolved, but growing research interest during the last decade has shed light in our knowledge in the field. This review summarizes the current concepts in the pathophysiology of obstructive jaundice-induced gut barrier dysfunction, analyzing pivotal factors, such as altered intestinal tight junctions expression, oxidative stress and imbalance of enterocyte proliferation and apoptosis. Clinicians handling patients with obstructive jaundice should not neglect protecting the intestinal barrier function before, during and after intervention for the relief of this condition, which may improve their patients’ outcome. PMID:18161914

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Cox2 and β-Catenin/T-cell Factor Signaling Intestinalize Human Esophageal Keratinocytes When Cultured under Organotypic Conditions

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Jianping Kong

2011-09-01

Full Text Available The incidence of esophageal adenocarcinoma (EAC is rising in the United States. An important risk factor for EAC is the presence of Barrett esophagus (BE. BE is the replacement of normal squamous esophageal epithelium with a specialized columnar epithelium in response to chronic acid and bile reflux. However, the emergence of BE from squamous keratinocytes has not yet been demonstrated. Our research has focused on this. Wnt and cyclooxygenase 2 (Cox2 are two pathways whose activation has been associated with BE and progression to EAC, but their role has not been tested experimentally. To explore their contribution, we engineered a human esophageal keratinocyte cell line to express either a dominant-active Wnt effector CatCLef or a Cox2 complementary DNA. In a two-dimensional culture environment, Cox2 expression increases cell proliferation and migration, but neither transgene induces known BE markers. In contrast, when these cells were placed into three-dimensional organotypic culture conditions, we observed more profound effects. CatCLef-expressing cells were more proliferative, developed a thicker epithelium, and upregulated Notch signaling and several BE markers including NHE2. Cox2 expression also increased cell proliferation and induced a thicker epithelium. More importantly, we observed cysts form within the epithelium, filled with intestinal mucins including Muc5B and Muc17. This suggests that Cox2 expression in a three-dimensional culture environment induces a lineage of mucin-secreting cells and supports an important causal role for Cox2 in BE pathogenesis. We conclude that in vitro modeling of BE pathogenesis can be improved by enhancing Wnt signaling and Cox2 activity and using three-dimensional organotypic culture conditions.

Induction of endoplasmic reticulum stress by deletion of Grp78 depletes Apc mutant intestinal epithelial stem cells.

Science.gov (United States)

van Lidth de Jeude, J F; Meijer, B J; Wielenga, M C B; Spaan, C N; Baan, B; Rosekrans, S L; Meisner, S; Shen, Y H; Lee, A S; Paton, J C; Paton, A W; Muncan, V; van den Brink, G R; Heijmans, J

2017-06-15

Intestinal epithelial stem cells are highly sensitive to differentiation induced by endoplasmic reticulum (ER) stress. Colorectal cancer develops from mutated intestinal epithelial stem cells. The most frequent initiating mutation occurs in Apc, which results in hyperactivated Wnt signalling. This causes hyperproliferation and reduced sensitivity to chemotherapy, but whether these mutated stem cells are sensitive to ER stress induced differentiation remains unknown. Here we examined this by generating mice in which both Apc and ER stress repressor chaperone Grp78 can be conditionally deleted from the intestinal epithelium. For molecular studies, we used intestinal organoids derived from these mice. Homozygous loss of Apc alone resulted in crypt elongation, activation of the Wnt signature and accumulation of intestinal epithelial stem cells, as expected. This phenotype was however completely rescued on activation of ER stress by additional deletion of Grp78. In these Apc-Grp78 double mutant animals, stem cells were rapidly lost and repopulation occurred by non-mutant cells that had escaped recombination, suggesting that Apc-Grp78 double mutant stem cells had lost self-renewal capacity. Although in Apc-Grp78 double mutant mice the Wnt signature was lost, these intestines exhibited ubiquitous epithelial presence of nuclear β-catenin. This suggests that ER stress interferes with Wnt signalling downstream of nuclear β-catenin. In conclusion, our findings indicate that ER stress signalling results in loss of Apc mutated intestinal epithelial stem cells by interference with the Wnt signature. In contrast to many known inhibitors of Wnt signalling, ER stress acts downstream of β-catenin. Therefore, ER stress poses a promising target in colorectal cancers, which develop as a result of Wnt activating mutations.

Expressions of TRPVs in the cholesteatoma epithelium.

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Do, Ba Hung; Koizumi, Hiroki; Ohbuchi, Toyoaki; Kawaguchi, Rintaro; Suzuki, Hideaki

2017-10-01

We have recently proposed a hypothesis that acid leakage through the cholesteatoma epithelium mediates bone resorption in middle ear cholesteatoma. In the present study, we investigated the expressions of transient receptor potential vanilloid (TRPV) channels, which have been shown to play roles in the regulation of epidermal barrier function, in the cholesteatoma epithelium in comparison with the normal skin. Cholesteatoma epithelium and postauricular skin were collected from 17 patients with primary acquired middle ear cholesteatoma who underwent tympanomastoidectomy. Expressions of TRPV1, TRPV3, TRPV4, and TRPV6 were explored by fluorescence immunohistochemistry and quantitative reverse transcription-polymerase chain reaction (qRT-PCR). TRPV1, TRPV3, TRPV4, and TRPV6 mRNAs were all detected by qRT-PCR both in the skin and cholesteatoma tissue. Immunohistochemical staining showed that TRPV1 and TRPV3 were positive in the viable cell layers of the epidermis of the skin, and only TRPV3 was positive in those of the cholesteatoma epithelium. The immunoreactivity for TRPV3 was significantly weaker in cholesteatoma than in the skin. The lower expression of TRPV3 in cholesteatoma may be one of the mechanisms underlying the increased permeability of this tissue. On the other hand, TRPV1, TRPV4, and TRPV6 are unlikely to be involved in the regulation of epithelial permeability in cholesteatoma.

Extract Against Toxic Sodium The Protective Role of Grape Seed Proanthocyanidins Nitrites and Gamma Irradiation Induced Histological Changes in Intestine and Urinary Bladder of Male Albino Rats

International Nuclear Information System (INIS)

Abd El- Azeem, M.G.; El-Nashar, D.E.M.

2010-01-01

Proanthocyanidins (a grape seed extract) possess a broad spectrum of biological activities. The present study was performed to investigate the effect of gamma radiation exposure and toxic sodium nitrites induced oxidative stress on the intestine and urinary bladder histologically and also to evaluate the possible protective role of proanthocyanidins. Seventy adult male albino rats, each weighing 95-105 g were used and divided into 7 groups as follows: The first group represents the control group. The second experimental group were exposed to 7 Gy gamma-rays as a single dose and sacrificed on the 7th day. The third experimental group received by a stomach tube daily 50 mg/kg b.wt of sodium nitrite for 4 weeks. The fourth experimental group received proanthocyanidins, Grape seed extracts (antioxidant) (100 mg/kg) body wt.) daily for seven days before irradiation and the continued for 14 days post irradiation. The fifth group of animals received grape seed extract after being exposed to gamma radiation for two weeks, while the sixth experimental group received the same antioxidant for seven days before and after received sodium nitrite (50 mg/kg) daily for 4 weeks. Finally, the seventh experimental groups was treated with the same antioxidant in same dose and time after received sodium nitrite for 4 weeks. The animals were then sacrificed on the end of each experimental duration. The results revealed that both gamma-radiation and sodium nitrite induced different histological changes in the intestine and urinary bladder of irradiated and sodium nitrite received animals. The effect of gamma radiation exposure showed marked degeneration of intestinal villi, vaculation in the lining epithelium cells and karyolytic nuclei. In addition, using sodium nitrite lead to necrosis of intestinal glandular cells. The effect of gamma radiation on urinary bladder was presented by, hyperplasia and vaculation of mucosal epithelium, congestion of blood capillaries. Rats from nitrite

Intestinal crosstalk – a new paradigm for understanding the gut as the “motor” of critical illness

Science.gov (United States)

Clark, Jessica A; Coopersmith, Craig M

2007-01-01

For more than 20 years, the gut has been hypothesized to be the “motor” of multiple organ dysfunction syndrome (MODS). As critical care research has evolved, there have been multiple mechanisms by which the gastrointestinal tract has been proposed to drive systemic inflammation. Many of these disparate mechanisms have proved to be important in the origin and propagation of critical illness. However, this has led to an unusual situation where investigators describing the gut as a “motor” revving the systemic inflammatory response syndrome (SIRS) are frequently describing wholly different processes to support their claim (i.e. increased apoptosis, altered tight junctions, translocation, cytokine production, crosstalk with commensal bacteria, etc). The purpose of this review is to present a unifying theory as to how the gut drives critical illness. Although the gastrointestinal tract is frequently described simply as “the gut,” it is actually made up of a) an epithelium, b) a diverse and robust immune arm, which contains the majority of immune cells in the body, and c) the commensal bacteria, which contain more cells than are present in the entire host organism. We propose that the intestinal epithelium, the intestinal immune system and the intestine’s endogenous bacteria all play vital roles driving MODS, and the complex crosstalk between these three interrelated portions of the gastrointestinal tract are cumulatively what makes the gut a “motor” of critical illness. PMID:17577136

Respiratory Epithelium Lined Cyst of the Maxilla: Differential Diagnosis

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C. P. Martinelli-Kläy

2017-01-01

Full Text Available Maxillary cysts, including the cysts lined by respiratory epithelium, can present a diagnostic challenge. We report an unusual case of a maxillary cyst on an endodontically treated tooth #16, in which the cavity was totally lined by a respiratory epithelium. The patient, a 35-year-old male, presented with a generalized chronic periodontitis and complained of a pain in the tooth #16 region. A periodontal pocket extending to the root apices with pus coming out from the gingival was found. A combined endodontic periodontal was observed on a panoramic radiography. CBCT-scan revealed a well-circumscribed radiolucent lesion at the apices of the distobuccal root of the 16. A communication with the right maxillary sinus cavity and a maxillary and ethmoidal sinusitis were also observed. The lesion was removed and histological examination revealed a cyst lined exclusively by respiratory epithelium. Ciliated and rare mucous cells were also observed. The diagnosis could evoke a surgical ciliated cyst mimicking the radicular cyst but the patient has no previous history of trauma or surgery in the maxillofacial region. It could also be an unusual radicular cyst in which the stratified squamous epithelium was destroyed by inflammation and replaced by a respiratory epithelium of the maxillary sinus.

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Regional Morphology and Transport of PAMAM Dendrimers Across Isolated Rat Intestinal Tissue.

Science.gov (United States)

Hubbard, Dallin; Bond, Tanner; Ghandehari, Hamidreza

2015-12-01

Intestinal permeability of PAMAM dendrimers has been observed, giving rationale for their use in oral drug delivery as potential carriers of associated molecules. This study assessed the apparent permeability coefficients (Papp) of dendrimers across isolated rat intestinal regional mucosae, along with estimation of the maximum non-toxic concentration. Caco-2 monolayers were also used to assess the comparative Papp values between isolated mucosae and cell culture models. Concentrations from 0.1 to 10 mM of anionic and cationic dendrimers were tested in mucosae to assess their Papp, membrane TEER, [(14)C]-mannitol Papp, and histology. 0.1 mM concentrations of dendrimers were assessed over 120 min in Caco-2 cell monolayers as concentrations above that were cytotoxic. Jejunal transport of dendrimers was higher than transport in colonic epithelium. Monolayer Papp values of dendrimers were comparable to those of jejunal mucosae. Mucosae exposed to dendrimer concentrations of 10 mM for 120 min caused significant reduction in TEER and changes in tissue morphology; however, G3.5 was the only analogue that caused significant TEER reduction and morphological changes at 1 mM concentrations. Transport in jejunal mucosae appears to be the greatest indicating that the small intestinal will be the most likely region to target for oral drug delivery using PAMAM dendrimers. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Neutrophil Interactions with Epithelial Expressed ICAM-1 Enhances Intestinal Mucosal Wound Healing

Science.gov (United States)

Sumagin, R; Brazil, JC; Nava, P; Nishio, H; Alam, A; Luissint, AC; Weber, DA; Neish, AS; Nusrat, A; Parkos, CA

2015-01-01

A characteristic feature of gastrointestinal tract inflammatory disorders, such as inflammatory bowel disease, is polymorphonuclear neutrophil (PMN) transepithelial migration (TEM) and accumulation in the gut lumen. PMN accumulation within the intestinal mucosa contributes to tissue injury. While epithelial infiltration by large numbers of PMNs results in mucosal injury, we found that PMN interactions with luminal epithelial membrane receptors may also play a role in wound healing. Intercellular adhesion molecule-1 (ICAM-1) is a PMN ligand that is upregulated on apical surfaces of intestinal epithelial cells under inflammatory conditions. In our study, increased expression of ICAM-1 resulted in enhanced PMN binding to the apical epithelium, which was associated with reduced PMN apoptosis. Following TEM, PMN adhesion to ICAM-1 resulted in activation of Akt and β-catenin signaling, increased epithelial-cell proliferation, and wound healing. Such responses were ICAM-1 dependent as engagement of epithelial ICAM-1 by antibody-mediated cross-linking yielded similar results. Furthermore, using an in-vivo biopsy-based, colonic-mucosal-injury model, we demonstrated epithelial ICAM-1 plays an important role in activation of epithelial Akt and β-catenin signaling and wound healing. These findings suggest that post-migrated PMNs within the intestinal lumen can regulate epithelial homeostasis, thereby identifying ICAM-1 as a potential therapeutic target for promoting mucosal wound healing. PMID:26732677

Neutrophil interactions with epithelial-expressed ICAM-1 enhances intestinal mucosal wound healing.

Science.gov (United States)

Sumagin, R; Brazil, J C; Nava, P; Nishio, H; Alam, A; Luissint, A C; Weber, D A; Neish, A S; Nusrat, A; Parkos, C A

2016-09-01

A characteristic feature of gastrointestinal tract inflammatory disorders, such as inflammatory bowel disease, is polymorphonuclear neutrophil (PMN) transepithelial migration (TEM) and accumulation in the gut lumen. PMN accumulation within the intestinal mucosa contributes to tissue injury. Although epithelial infiltration by large numbers of PMNs results in mucosal injury, we found that PMN interactions with luminal epithelial membrane receptors may also play a role in wound healing. Intercellular adhesion molecule-1 (ICAM-1) is a PMN ligand that is upregulated on apical surfaces of intestinal epithelial cells under inflammatory conditions. In our study, increased expression of ICAM-1 resulted in enhanced PMN binding to the apical epithelium, which was associated with reduced PMN apoptosis. Following TEM, PMN adhesion to ICAM-1 resulted in activation of Akt and β-catenin signaling, increased epithelial-cell proliferation, and wound healing. Such responses were ICAM-1 dependent as engagement of epithelial ICAM-1 by antibody-mediated cross-linking yielded similar results. Furthermore, using an in-vivo biopsy-based, colonic-mucosal-injury model, we demonstrated epithelial ICAM-1 has an important role in activation of epithelial Akt and β-catenin signaling and wound healing. These findings suggest that post-migrated PMNs within the intestinal lumen can regulate epithelial homeostasis, thereby identifying ICAM-1 as a potential therapeutic target for promoting mucosal wound healing.

The Effects of Deoxynivalenol and Zearalenone on the Pig Large Intestine. A Light and Electron Microscopy Study

Directory of Open Access Journals (Sweden)

Barbara Przybylska-Gornowicz

2018-04-01

Full Text Available The contamination of feed with mycotoxins results in reduced growth, feed refusal, immunosuppression, and health problems. Deoxynivalenol (DON and zearalenone (ZEN are among the most important mycotoxins. The aim of the study was to examine the effects of low doses of these mycotoxins on the histological structure and ultrastructure of the large intestine in the pig. The study was performed on 36 immature gilts of mixed breed (White Polish Big × Polish White Earhanging, which were divided into four groups administrated per os with ZEN at 40 µg/kg BW, DON at 12 µg/kg BW, a mixture of ZEN (40 µg/kg BW and DON (12 µg/kg BW or a placebo. The pigs were killed by intravenous overdose of pentobarbital after one, three, and six weeks of treatment. The cecum, ascending and descending colon samples were prepared for light and electron microscopy. Administration of toxins did not influence the architecture of the mucosa and submucosa in the large intestine. ZEN and ZEN + DON significantly decreased the number of goblet cells in the cecum and descending colon. The mycotoxins changed the number of lymphocytes and plasma cells in the large intestine, which usually increased in number. However, this effect differed between the intestine segments and toxins. Mycotoxins induced some changes in the ultrastructure of the mucosal epithelium. They did not affect the expression of proliferative cell nuclear antigen and the intestinal barrier permeability. The obtained results indicate that mycotoxins especially ZEN may influence the defense mechanisms of the large intestine.

In vitro characterization of cadmium transport along the gastro-intestinal tract of freshwater rainbow trout (Oncorhynchus mykiss)

International Nuclear Information System (INIS)

Klinck, Joel S.; Wood, Chris M.

2011-01-01

An in vitro gut sac technique was used to examine the mechanism(s) of cadmium (Cd) uptake along the gastro-intestinal tract (GIT) of rainbow trout (Oncorhynchus mykiss). The spatial distribution of Cd between three compartments (mucus-binding, mucosal epithelium, and transport into blood space) was determined using a modified Cortland saline containing 50 μM Cd (as CdCl 2 ) labeled with 109 Cd radiotracer. Taking into account total surface areas, the order of relative importance for total Cd uptake rate was: posterior intestine > anterior intestine > stomach > mid intestine. Cd transport was not inhibited by experimentally reducing fluid transport rates by manipulation of osmotic gradients using mannitol, but was sensitive to internal luminal pressure changes, suggesting a mechanosensitive pathway. Q 10 values (1, 11, and 19 o C) indicated a facilitated transport of Cd in the anterior- and mid-intestine. The effects of 10 mM Ca on the kinetics of Cd uptake suggest the presence of a common uptake pathway for Cd and Ca in the stomach, anterior-, and mid-intestine. Further evidence of a shared route of entry was found using three Ca channel blockers, lanthanum, verapamil, and nifedipine: both voltage-insensitive and voltage-sensitive Ca channels appear to be present in either some, or all portions of the GIT. Elevated Fe (500 μM), Mg (50 mM), and Zn (500 μM) showed varying degrees of inhibition of Cd transport depending on the compartment and segment of the GIT. Overall it appears that there are multiple sites, and mechanisms, of Cd uptake along the GIT of rainbow trout.

In Inflamed Intestinal Tissues and Epithelial Cells, Interleukin 22 Signaling Increases Expression of H19 Long Noncoding RNA, Which Promotes Mucosal Regeneration.

Science.gov (United States)

Geng, Hua; Bu, Heng-Fu; Liu, Fangyi; Wu, Longtao; Pfeifer, Karl; Chou, Pauline M; Wang, Xiao; Sun, Jiaren; Lu, Lu; Pandey, Ashutosh; Bartolomei, Marisa S; De Plaen, Isabelle G; Wang, Peng; Yu, Jindan; Qian, Jiaming; Tan, Xiao-Di

2018-04-03

Inflammation affects regeneration of the intestinal epithelia; long non-coding RNAs (lncRNAs) regulate cell functions, such as proliferation, differentiation, and migration. We investigated the mechanisms by which the lncRNA H19, imprinted maternally expressed transcript (H19) regulates regeneration of intestinal epithelium using cell cultures and mouse models of inflammation. We performed RNA-sequencing transcriptome analyses of intestinal tissues from mice with lipopolysaccharide (LPS)-induced sepsis to identify lncRNAs associated with inflammation; findings were confirmed by quantitative real-time polymerase chain reaction and in situ hybridization analyses of intestinal tissues from mice with sepsis or dextran sulfate sodium (DSS)-induced mucosal wound healing and patients with ulcerative colitis compared to healthy individuals (controls). We screened cytokines for their ability to induce expression of H19 in HT-29 cells and intestinal epithelial cells (IECs), and confirmed findings in crypt epithelial organoids derived from mouse small intestine. IECs were incubated with different signal transduction inhibitors and effects on H19 lncRNA levels were measured. We assessed intestinal epithelial proliferation or regeneration in H19 ΔEx1/+ mice given LPS or DSS vs wild-type littermates (control mice). H19 was overexpressed in IECs using lentiviral vectors and cell proliferation was measured. We performed RNA antisense purification, RNA immunoprecipitation, and luciferase reporter assays to study functions of H19 in IECs. In RNA-sequencing transcriptome analysis of lncRNA expression in intestinal tissues from mice, we found levels of H19 only changed significantly with LPS exposure. Levels of H19 lncRNA increased in intestinal tissues of patients with ulcerative colitis, mice with LPS-induced sepsis, or mice with DSS-induced colitis, compared with controls. Increased H19 lncRNA localized to epithelial cells in the intestine, regardless of Lgr5 messenger RNA

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Lifescience Database Archive (English)

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File list: His.Oth.20.AllAg.Olfactory_epithelium [Chip-atlas[Archive

Lifescience Database Archive (English)

Full Text Available His.Oth.20.AllAg.Olfactory_epithelium mm9 Histone Others Olfactory epithelium SRX18...378533,SRX378536,SRX378534,SRX472910 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/His.Oth.20.AllAg.Olfactory_epithelium.bed ...

Angiotensin II induces apoptosis in intestinal epithelial cells through the AT2 receptor, GATA-6 and the Bax pathway

International Nuclear Information System (INIS)

Sun, Lihua; Wang, Wensheng; Xiao, Weidong; Liang, Hongyin; Yang, Yang; Yang, Hua

2012-01-01

Highlights: ► Ang II-induced apoptosis in intestinal epithelial cell through AT2 receptor. ► The apoptosis process involves in the Bax/Bcl-2 intrinsic pathway. ► GATA-6 short hairpin RNA reduced Bax expression, but not Bcl-2. ► GATA-6 may play a critical role in apoptosis in response to the Ang II challenge. -- Abstract: Angiotensin II (Ang II) has been shown to play an important role in cell apoptosis. However, the mechanisms of Ang-II-induced apoptosis in intestinal epithelial cells are not fully understood. GATA-6 is a zinc finger transcription factor expressed in the colorectal epithelium, which directs cell proliferation, differentiation and apoptosis. In the present study we investigated the underlying mechanism of which GATA-6 affects Ang-II induced apoptosis in intestinal epithelial cells. The in vitro intestinal epithelial cell apoptosis model was established by co-culturing Caco-2 cells with Ang II. Pretreatment with Angiotensin type 2 (AT2) receptor antagonist, PD123319, significantly reduced the expression of Bax and prevented the Caco-2 cells apoptosis induced by Ang II. In addition, Ang II up-regulated the expression of GATA-6. Interestingly, GATA-6 short hairpin RNA prevented Ang II-induced intestinal epithelial cells apoptosis and reduced the expression of Bax, but not Bcl-2. Taken together, the present study suggests that Angiotensin II promotes apoptosis in intestinal epithelial cells through GATA-6 and the Bax pathway in an AT2 receptor-dependent manner.

Ecophysiology of the developing total bacterial and Lactobacillus communities in the terminal small intestine of weaning piglets

NARCIS (Netherlands)

Pieper, R.; Janzcyk, P.; Zeyner, A.; Smidt, H.; Guiard, V.; Souffrant, W.B.

2008-01-01

Weaning of the pig is generally regarded as a stressful event which could lead to clinical implications because of the changes in the intestinal ecosystem. The functional properties of microbiota inhabiting the pig's small intestine (SI), including lactobacilli which are assumed to exert

Salmonella Typhi Colonization Provokes Extensive Transcriptional Changes Aimed at Evading Host Mucosal Immune Defense During Early Infection of Human Intestinal Tissue

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K.P. Nickerson

2018-05-01

Full Text Available Commensal microorganisms influence a variety of host functions in the gut, including immune response, glucose homeostasis, metabolic pathways and oxidative stress, among others. This study describes how Salmonella Typhi, the pathogen responsible for typhoid fever, uses similar strategies to escape immune defense responses and survive within its human host. To elucidate the early mechanisms of typhoid fever, we performed studies using healthy human intestinal tissue samples and “mini-guts,” organoids grown from intestinal tissue taken from biopsy specimens. We analyzed gene expression changes in human intestinal specimens and bacterial cells both separately and after colonization. Our results showed mechanistic strategies that S. Typhi uses to rearrange the cellular machinery of the host cytoskeleton to successfully invade the intestinal epithelium, promote polarized cytokine release and evade immune system activation by downregulating genes involved in antigen sampling and presentation during infection. This work adds novel information regarding S. Typhi infection pathogenesis in humans, by replicating work shown in traditional cell models, and providing new data that can be applied to future vaccine development strategies. Keywords: Typhoid fever, Salmonella, Snapwell™ system, Human tissue, Terminal ileum, Immune system, Innate immunity, Immune evasion, Host-pathogen interaction, Vaccine development, Intestinal organoids, Organoid monolayer

FMRFamide- and neurotensin-immunoreactive elements in the intestine of some polyclad and triclad flatworms (Turbellaria).

Science.gov (United States)

Punin MYu; Markosova, T G

2000-01-01

By means of immunohistochemistry with antisera to tetrapeptide FMRFamide and regulatory peptides neurotensin and calcitonin intestines of marine turbellarians Notoplana atomata, N. humilis (Polycladida) and Procerodes littoralis (Tricladida) were investigated. In all flatworms polymorphous cells and processes reacting with antibodies to FMRFamide and neurotensin but not with calcitonin were revealed. These cell elements are localized both in the epithelium and beneath it. FMRFamide-immunoreactive cells and processes of investigated turbellarians and neurotensin-immunoreactive elements in P. littoralis obviously belong to the nervous system, while intraepithelial neurotensin-immunoreactive cells of polyclads share some morphological features with endocrine-like cells.

[Adult intestinal malrotation associated with intestinal volvulus].

Science.gov (United States)

Hernando-Almudí, Ernesto; Cerdán-Pascual, Rafael; Vallejo-Bernad, Cristina; Martín-Cuartero, Joaquín; Sánchez-Rubio, María; Casamayor-Franco, Carmen

Intestinal malrotation is a congenital anomaly of the intestinal rotation and fixation, and usually occurs in the neonatal age. Description of a clinical case associated with acute occlusive symptoms. A case of intestinal malrotation is presented in a previously asymptomatic woman of 46 years old with an intestinal obstruction, with radiology and surgical findings showing an absence of intestinal rotation. Intestinal malrotation in adults is often asymptomatic, and is diagnosed as a casual finding during a radiological examination performed for other reasons. Infrequently, it can be diagnosed in adults, associated with an acute abdomen. Copyright © 2016 Academia Mexicana de Cirugía A.C. Publicado por Masson Doyma México S.A. All rights reserved.

[Characterization of stem cells derived from the neonatal auditory sensory epithelium].

Science.gov (United States)

Diensthuber, M; Heller, S

2010-11-01

In contrast to regenerating hair cell-bearing organs of nonmammalian vertebrates the adult mammalian organ of Corti appears to have lost its ability to maintain stem cells. The result is a lack of regenerative ability and irreversible hearing loss following auditory hair cell death. Unexpectedly, the neonatal auditory sensory epithelium has recently been shown to harbor cells with stem cell features. The origin of these cells within the cochlea's sensory epithelium is unknown. We applied a modified neurosphere assay to identify stem cells within distinct subregions of the neonatal mouse auditory sensory epithelium. Sphere cells were characterized by multiple markers and morphologic techniques. Our data reveal that both the greater and the lesser epithelial ridge contribute to the sphere-forming stem cell population derived from the auditory sensory epithelium. These self-renewing sphere cells express a variety of markers for neural and otic progenitor cells and mature inner ear cell types. Stem cells can be isolated from specific regions of the auditory sensory epithelium. The distinct features of these cells imply a potential application in the development of a cell replacement therapy to regenerate the damaged sensory epithelium.

Bone Marrow Derivation of Interstitial Cells of Cajal in Small Intestine Following Intestinal Injury

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Dengqun Liu

2010-01-01

Full Text Available Interstitial cells of Cajal (ICCs in gastrointestinal tract are specialized cells serving as pacemaker cells. The origin of ICCs is currently not fully characterized. In this work, we aimed to study whether bone marrow-derived cells (BMDCs could contribute to the origin of ICCs in the muscular plexus of small intestine using GFP-C57BL/6 chimeric mice.Engraftment of BMDCs in the intestine was investigated for GFP expression. GFP positive bone marrow mononuclear cells reached a proportion of 95.65%±3.72% at different times in chimerism. Donor-derived cells distributed widely in all the layers of the gastrointestinal tract. There were GFP positive BMDCs in the myenteric plexus, which resembled characteristics of ICCs, including myenteric location, c-Kit positive staining, and ramified morphology. Donor-derived ICCs in the myenteric plexus contributed to a percentage ranging 9.25%±4.9% of all the ICCs in the myenteric plexus. In conclusion, here we described that donor-derived BMDCs might differentiate into gastrointestinal ICCs after radiation injury, which provided an alternative source for the origin of the ICCs in the muscular plexus of adult intestine. These results further identified the plasticity of BMDCs and indicated therapeutic implications of BMDCs for the gastrointestinal dysmotility caused by ICCs disorders.

The protective effect of infliximab on cisplatin-induced intestinal tissue toxicity.

Science.gov (United States)

Aydin, I; Kalkan, Y; Ozer, E; Yucel, A F; Pergel, A; Cure, E; Cure, M C; Sahin, D A

2014-01-01

Cisplatin (CP) is a popular chemotherapeutic agent. However, high doses of CP may lead to severe side effects to the gastrointestinal system. The aim of this study was to investigate the protective effects of infliximab on small intestine injury induced by high doses of CP. The A total of 30 rats were equally divided into three groups, including sham (C), cisplatin (CP), and cisplatin + infliximab (CPI). The CP group was treated with 7 mg/kg intraperitoneal cisplatin, and a laparotomy was performed 5 days later. The CPI group received 7 mg/kg infliximab intraperitoneally, were administered 7 mg/kg cisplatin 4 days later, and a laparotomy was performed 5 days after receiving cisplatin. Histopathological and immunohistochemical analysis of small intestine tissue sections were performed, and superoxide dismutase, malondialdehyde, and TNF-α levels were measured. Histopathological evaluation revealed that the CP group had damage in the epithelium and connective tissue, but this damage was significantly improved in the CPI group (p < 0.05). In addition, these histopathological findings were confirmed by biochemical analyses. These results suggest that infliximab is protective against the adverse effects of CP.

Temperature modulates the effects of ocean acidification on intestinal ion transport in Atlantic cod, Gadus morhua

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Marian Yong-An Hu

2016-06-01

Full Text Available CO2-driven seawater acidification has been demonstrated to enhance intestinal bicarbonate secretion rates in teleosts, leading to an increased release of CaCO3 under simulated ocean acidification scenarios. In this study, we investigated if increasing CO2 levels stimulate the intestinal acid–base regulatory machinery of Atlantic cod (Gadus morhua and whether temperatures at the upper limit of thermal tolerance stimulate or counteract ion regulatory capacities. Juvenile G. morhua were acclimated for four weeks to three CO2 levels (550, 1,200 and 2,200 μatm covering present and near-future natural variability, at optimum (10°C and summer maximum temperature (18°C, respectively. Immunohistochemical analyses revealed the subcellular localization of ion transporters, including Na+/K+-ATPase (NKA, Na+/H+-exchanger 3 (NHE3, Na+/HCO3- cotransporter (NBC1, pendrin-like Cl-/HCO3- exchanger (SLC26a6, V-type H+-ATPase subunit a (VHA and Cl- channel 3 (CLC3 in epithelial cells of the anterior intestine. At 10°C, proteins and mRNA were generally up-regulated for most transporters in the intestinal epithelium after acclimation to higher CO2 levels. This supports recent findings demonstrating increased intestinal HCO3- secretion rates in response to CO2 induced seawater acidification. At 18°C, mRNA expression and protein concentrations of most ion transporters remained unchanged or were even decreased, suggesting thermal compensation. This response may be energetically favorable to retain blood HCO3- levels to stabilize pHe, but may negatively affect intestinal salt and water resorption of marine teleosts in future oceans.

Dynamics of Bovine Sperm Interaction with Epithelium Differ Between Oviductal Isthmus and Ampulla1

Science.gov (United States)

Ardon, Florencia; Markello, Ross D.; Hu, Lian; Deutsch, Zarah I.; Tung, Chih-Kuan; Wu, Mingming; Suarez, Susan S.

2016-01-01

In mammals, many sperm that reach the oviduct are held in a reservoir by binding to epithelium. To leave the reservoir, sperm detach from the epithelium; however, they may bind and detach again as they ascend into the ampulla toward oocytes. In order to elucidate the nature of binding interactions along the oviduct, we compared the effects of bursts of strong fluid flow (as would be caused by oviductal contractions), heparin, and hyperactivation on detachment of bovine sperm bound in vitro to epithelium on intact folds of isthmic and ampullar mucosa. Intact folds of oviductal mucosa were used to represent the strong attachments of epithelial cells to each other and to underlying connective tissue that exist in vivo. Effects of heparin on binding were tested because heparin binds to the Binder of SPerm (BSP) proteins that attach sperm to oviductal epithelium. Sperm bound by their heads to beating cilia on both isthmic and ampullar epithelia and could not be detached by strong bursts of fluid flow. Addition of heparin immediately detached sperm from isthmic epithelium but not ampullar epithelium. Addition of 4-aminopyridine immediately stimulated hyperactivation of sperm but did not detach them from isthmic or ampullar epithelium unless added with heparin. These observations indicate that the nature of binding of sperm to ampullar epithelium differs from that of binding to isthmic epithelium; specifically, sperm bound to isthmic epithelium can be detached by heparin alone, while sperm bound to ampullar epithelium requires both heparin and hyperactivation to detach from the epithelium. PMID:27605344

Creatine maintains intestinal homeostasis and protects against colitis.

Science.gov (United States)

Turer, Emre; McAlpine, William; Wang, Kuan-Wen; Lu, Tianshi; Li, Xiaohong; Tang, Miao; Zhan, Xiaoming; Wang, Tao; Zhan, Xiaowei; Bu, Chun-Hui; Murray, Anne R; Beutler, Bruce

2017-02-14

Creatine, a nitrogenous organic acid, replenishes cytoplasmic ATP at the expense of mitochondrial ATP via the phosphocreatine shuttle. Creatine levels are maintained by diet and endogenous synthesis from arginine and glycine. Glycine amidinotransferase (GATM) catalyzes the rate-limiting step of creatine biosynthesis: the transfer of an amidino group from arginine to glycine to form ornithine and guanidinoacetate. We screened 36,530 third-generation germline mutant mice derived from N -ethyl- N -nitrosourea-mutagenized grandsires for intestinal homeostasis abnormalities after oral administration of dextran sodium sulfate (DSS). Among 27 colitis susceptibility phenotypes identified and mapped, one was strongly correlated with a missense mutation in Gatm in a recessive model of inheritance, and causation was confirmed by CRISPR/Cas9 gene targeting. Supplementation of homozygous Gatm mutants with exogenous creatine ameliorated the colitis phenotype. CRISPR/Cas9-targeted ( Gatm c/c ) mice displayed a normal peripheral immune response and immune cell homeostasis. However, the intestinal epithelium of the Gatm c/c mice displayed increased cell death and decreased proliferation during DSS treatment. In addition, Gatm c/c colonocytes showed increased metabolic stress in response to DSS with higher levels of phospho-AMPK and lower levels of phosphorylation of mammalian target of rapamycin (phospho-mTOR). These findings establish an in vivo requirement for rapid replenishment of cytoplasmic ATP within colonic epithelial cells in the maintenance of the mucosal barrier after injury.

Correlation between oral drug absorption in humans and apparent drug permeability coefficients in human intestinal epithelial (Caco-2) cells

International Nuclear Information System (INIS)

Artursson, P.; Karlsson, J.

1991-01-01

Monolayers of a well differentiated human intestinal epithelial cell line, Caco-2, were used as a model to study passive drug absorption across the intestinal epithelium. Absorption rate constants (expressed as apparent permeability coefficients) were determined for 20 drugs and peptides with different structural properties. The permeability coefficients ranged from approximately 5 x 10 - 8 to 5 x 10 - 5 cm/s. A good correlation was obtained between data on oral absorption in humans and the results in the Caco-2 model. Drugs that are completely absorbed in humans had permeability coefficients greater than 1 x 10 - 6 cm/s. Drugs that are absorbed to greater than 1% but less than 100% had permeability coefficients of 0.1-1.0 x 10 - 6 cm/s while drugs and peptides that are absorbed to less than 1% had permeability coefficients of less than or equal to 1 x 10 - 7 cm/s. The results indicate that Caco-2 monolayers can be used as a model for studies on intestinal drug absorption

Syndapin/SDPN-1 is required for endocytic recycling and endosomal actin association in the Caenorhabditis elegans intestine

Science.gov (United States)

Gleason, Adenrele M.; Nguyen, Ken C. Q.; Hall, David H.; Grant, Barth D.

2016-01-01

Syndapin/pascin-family F-BAR domain proteins bind directly to membrane lipids and are associated with actin dynamics at the plasma membrane. Previous reports also implicated mammalian syndapin 2 in endosome function during receptor recycling, but precise analysis of a putative recycling function for syndapin in mammalian systems is difficult because of its effects on the earlier step of endocytic uptake and potential redundancy among the three separate genes that encode mammalian syndapin isoforms. Here we analyze the endocytic transport function of the only Caenorhabditis elegans syndapin, SDPN-1. We find that SDPN-1 is a resident protein of the early and basolateral recycling endosomes in the C. elegans intestinal epithelium, and sdpn-1 deletion mutants display phenotypes indicating a block in basolateral recycling transport. sdpn-1 mutants accumulate abnormal endosomes positive for early endosome and recycling endosome markers that are normally separate, and such endosomes accumulate high levels of basolateral recycling cargo. Furthermore, we observed strong colocalization of endosomal SDPN-1 with the F-actin biosensor Lifeact and found that loss of SDPN-1 greatly reduced Lifeact accumulation on early endosomes. Taken together, our results provide strong evidence for an in vivo function of syndapin in endocytic recycling and suggest that syndapin promotes transport via endosomal fission. PMID:27630264

The many faces of intestinal tract gastric heterotopia; a series of four cases highlighting clinical and pathological heterogeneity.

Science.gov (United States)

Nasir, Aqsa; Amateau, Stuart K; Khan, Sabina; Simpson, Ross W; Snover, Dale C; Amin, Khalid

2018-04-01

Gastric heterotopia of the intestinal tract can have a diverse clinicopathologic presentation, resulting in a diagnostic dilemma. We present a series of four cases, two male and two female patients with age range of 31-82 years, found in the duodenum, jejunum, and transverse colon. The most common and rather unusual clinical presentation was iron deficiency anemia, seen in three cases, while one patient presented with abdominal pain. Endoscopically, two cases were visualized as pedunculated polyps and two as sessile/plaque-like lesions. Polypectomy was performed in three patients, and one patient underwent biopsy followed by resection. Two cases showed oxyntic-type epithelium, and two cases exhibited pyloric-type gastric epithelium. Three patients were relieved of their presenting symptoms after therapeutic procedures with no evidence of recurrence noted on follow-up. Follow-up was not available on one patient. This case series highlights a diverse clinicopathologic spectrum of gastric heterotopia. Accurate diagnosis is essential for proper management. Copyright © 2018. Published by Elsevier Inc.

The ureteric bud epithelium: morphogenesis and roles in metanephric kidney patterning.

Science.gov (United States)

Nagalakshmi, Vidya K; Yu, Jing

2015-03-01

The mammalian metanephric kidney is composed of two epithelial components, the collecting duct system and the nephron epithelium, that differentiate from two different tissues -the ureteric bud epithelium and the nephron progenitors, respectively-of intermediate mesoderm origin. The collecting duct system is generated through reiterative ureteric bud branching morphogenesis, whereas the nephron epithelium is formed in a process termed nephrogenesis, which is initiated with the mesenchymal-epithelial transition of the nephron progenitors. Ureteric bud branching morphogenesis is regulated by nephron progenitors, and in return, the ureteric bud epithelium regulates nephrogenesis. The metanephric kidney is physiologically divided along the corticomedullary axis into subcompartments that are enriched with specific segments of these two epithelial structures. Here, we provide an overview of the major molecular and cellular processes underlying the morphogenesis and patterning of the ureteric bud epithelium and its roles in the cortico-medullary patterning of the metanephric kidney. © 2015 Wiley Periodicals, Inc.

Intestinal Integrity Biomarkers in Early Antiretroviral-Treated Perinatally HIV-1-Infected Infants.

Science.gov (United States)

Koay, Wei Li A; Lindsey, Jane C; Uprety, Priyanka; Bwakura-Dangarembizi, Mutsa; Weinberg, Adriana; Levin, Myron J; Persaud, Deborah

2018-05-12

Biomarkers of intestinal integrity (intestinal fatty acid binding protein (iFABP) and zonulin), were compared in early antiretroviral-treated, HIV-1-infected (HIV+; n=56) African infants and HIV-exposed but uninfected (HEU; n=53) controls. Despite heightened inflammation and immune activation in HIV+ infants, iFABP and zonulin levels at three months of age were not different from those in HEU infants, and largely not correlated with inflammatory and immune activation biomarkers. However, zonulin levels increased, and became significantly higher in HIV+ compared to HEU infants by five months of age despite ART-suppression. These findings have implications for intestinal integrity biomarker profiling in perinatal HIV-1 infection.

Tracheal epithelium cell volume responses to hyperosmolar, isosmolar and hypoosmolar solutions: relation to epithelium-derived relaxing factor (EpDRF effects

Directory of Open Access Journals (Sweden)

Jeffrey S. Fedan

2013-10-01

Full Text Available In asthmatic patients, inhalation of hyperosmolar saline or D-mannitol (D-M elicits bronchoconstriction, but in healthy subjects exercise causes bronchodilation. Hyperventilation causes drying of airway surface liquid (ASL and increases its osmolarity. Hyperosmolar challenge of airway epithelium releases epithelium-derived relaxing factor (EpDRF, which relaxes the airway smooth muscle. This pathway could be involved in exercise-induced bronchodilation. Little is known of ASL hyperosmolarity effects on epithelial function. We investigated the effects of osmolar challenge maneuvers on dispersed and adherent guinea-pig tracheal epithelial cells to examine the hypothesis that EpDRF-mediated relaxation is associated with epithelial cell shrinkage. Enzymatically-dispersed cells shrank when challenged with ≥10 mOsM added D M, urea or NaCl with a concentration-dependence that mimics relaxation of the of isolated, perfused tracheas (IPT. Cells shrank when incubated in isosmolar N-methyl-D-glucamine (NMDG chloride, Na gluconate (Glu, NMDG-Glu, K-Glu and K2SO4, and swelled in isosmolar KBr and KCl. However, isosmolar challenge is not a strong stimulus of relaxation in IPTs. In previous studies amiloride and 4,4' diisothiocyano 2,2' stilbenedisulfonic acid (DIDS inhibited relaxation of IPT to hyperosmolar challenge, but had little effect on shrinkage of dispersed cells. Confocal microscopy in tracheal segments showed that adherent epithelium is refractory to low hyperosmolar concentrations that induce dispersed cell shrinkage and relaxation of IPT. Except for gadolinium and erythro 9 (2 hydroxy 3 nonyladenine (EHNA, actin and microtubule inhibitors and membrane permeabilizing agents did not affect on ion transport by adherent epithelium or shrinkage responses of dispersed cells. Our studies dissociate relaxation of IPT from cell shrinkage after hyperosmolar challenge of airway epithelium .

Changes in the Adult Vertebrate Auditory Sensory Epithelium After Trauma

Science.gov (United States)

Oesterle, Elizabeth C.

2012-01-01

Auditory hair cells transduce sound vibrations into membrane potential changes, ultimately leading to changes in neuronal firing and sound perception. This review provides an overview of the characteristics and repair capabilities of traumatized auditory sensory epithelium in the adult vertebrate ear. Injured mammalian auditory epithelium repairs itself by forming permanent scars but is unable to regenerate replacement hair cells. In contrast, injured non-mammalian vertebrate ear generates replacement hair cells to restore hearing functions. Non-sensory support cells within the auditory epithelium play key roles in the repair processes. PMID:23178236

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Lifescience Database Archive (English)

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File list: NoD.Oth.05.AllAg.Olfactory_epithelium [Chip-atlas[Archive

Lifescience Database Archive (English)

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File list: NoD.Oth.20.AllAg.Olfactory_epithelium [Chip-atlas[Archive

Lifescience Database Archive (English)

Full Text Available NoD.Oth.20.AllAg.Olfactory_epithelium mm9 No description Others Olfactory epithelium... http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/NoD.Oth.20.AllAg.Olfactory_epithelium.bed ...

File list: NoD.Oth.50.AllAg.Olfactory_epithelium [Chip-atlas[Archive

Lifescience Database Archive (English)

Full Text Available NoD.Oth.50.AllAg.Olfactory_epithelium mm9 No description Others Olfactory epithelium... http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/NoD.Oth.50.AllAg.Olfactory_epithelium.bed ...

Intestinal bacteria and the regulation of immune cell homeostasis.

Science.gov (United States)

Hill, David A; Artis, David

2010-01-01

The human intestine is colonized by an estimated 100 trillion bacteria. Some of these bacteria are essential for normal physiology, whereas others have been implicated in the pathogenesis of multiple inflammatory diseases including IBD and asthma. This review examines the influence of signals from intestinal bacteria on the homeostasis of the mammalian immune system in the context of health and disease. We review the bacterial composition of the mammalian intestine, known bacterial-derived immunoregulatory molecules, and the mammalian innate immune receptors that recognize them. We discuss the influence of bacterial-derived signals on immune cell function and the mechanisms by which these signals modulate the development and progression of inflammatory disease. We conclude with an examination of successes and future challenges in using bacterial communities or their products in the prevention or treatment of human disease.

Mechanisms underlying epithelium-dependent relaxation in rat bronchioles

DEFF Research Database (Denmark)

Kroigaard, Christel; Dalsgaard, Thomas; Simonsen, Ulf

2010-01-01

This study investigated the mechanisms underlying epithelium-derived hyperpolarizing factor (EpDHF)-type relaxation in rat bronchioles. Immunohistochemistry was performed, and rat bronchioles and pulmonary arteries were mounted in microvascular myographs for functional studies. An opener of small...... (SK(Ca)) and intermediate (IK(Ca))-conductance calcium-activated potassium channels, NS309 (6,7-dichloro-1H-indole-2,3-dione 3-oxime) was used to induce EpDHF-type relaxation. IK(Ca) and SK(Ca)3 positive immunoreactions were observed mainly in the epithelium and endothelium of bronchioles and arteries......, respectively. In 5-hydroxytryptamine (1 microM)-contracted bronchioles (828 +/- 20 microm, n = 84) and U46619 (0.03 microM)-contracted arteries (720 +/- 24 microm, n = 68), NS309 (0.001-10 microM) induced concentration-dependent relaxations that were reduced by epithelium/endothelium removal and by blocking IK...

Intestinal Fork Head Regulates Nutrient Absorption and Promotes Longevity

Directory of Open Access Journals (Sweden)

Ekin Bolukbasi

2017-10-01

Full Text Available Reduced activity of nutrient-sensing signaling networks can extend organismal lifespan, yet the underlying biology remains unclear. We show that the anti-aging effects of rapamycin and reduced intestinal insulin/insulin growth factor (IGF signaling (IIS require the Drosophila FoxA transcription factor homolog Fork Head (FKH. Intestinal FKH induction extends lifespan, highlighting a role for the gut. FKH binds to and is phosphorylated by AKT and Target of Rapamycin. Gut-specific FKH upregulation improves gut barrier function in aged flies. Additionally, it increases the expression of nutrient transporters, as does lowered IIS. Evolutionary conservation of this effect of lowered IIS is suggested by the upregulation of related nutrient transporters in insulin receptor substrate 1 knockout mouse intestine. Our study highlights a critical role played by FKH in the gut in mediating anti-aging effects of reduced IIS. Malnutrition caused by poor intestinal absorption is a major problem in the elderly, and a better understanding of the mechanisms involved will have important therapeutic implications for human aging.

Development of the ovarian follicular epithelium.

Science.gov (United States)

Rodgers, R J; Lavranos, T C; van Wezel, I L; Irving-Rodgers, H F

1999-05-25

A lot is known about the endocrine control of the development of ovarian follicles, but a key question now facing researchers is which molecular and cellular processes take part in control of follicular growth and development. The growth and development of ovarian follicles occurs postnatally and throughout adult life. In this review, we focus on the follicular epithelium (membrana granulosa) and its basal lamina. We discuss a model of how granulosa cells arise from a population of stem cells and then enter different lineages before differentiation. The structure of the epithelium at the antral stage of development is presented, and the effects that follicle growth has on the behavior of the granulosa cells are discussed. Finally, we discuss the evidence that during follicle development the follicular basal lamina changes in composition. This would be expected if the behavior of the granulosa cells changes, or if the permeability of the basal lamina changes. It will be evident that the follicular epithelium has similarities to other epithelia in the body, but that it is more dynamic, as gross changes occur during the course of follicle development. This basic information will be important for the development of future reproductive technologies in both humans and animals, and possibly for understanding polycystic ovarian syndrome in women.

Oral absorption of peptides and nanoparticles across the human intestine: Opportunities, limitations and studies in human tissues.

Science.gov (United States)

Lundquist, P; Artursson, P

2016-11-15

In this contribution, we review the molecular and physiological barriers to oral delivery of peptides and nanoparticles. We discuss the opportunities and predictivity of various in vitro systems with special emphasis on human intestine in Ussing chambers. First, the molecular constraints to peptide absorption are discussed. Then the physiological barriers to peptide delivery are examined. These include the gastric and intestinal environment, the mucus barrier, tight junctions between epithelial cells, the enterocytes of the intestinal epithelium, and the subepithelial tissue. Recent data from human proteome studies are used to provide information about the protein expression profiles of the different physiological barriers to peptide and nanoparticle absorption. Strategies that have been employed to increase peptide absorption across each of the barriers are discussed. Special consideration is given to attempts at utilizing endogenous transcytotic pathways. To reliably translate in vitro data on peptide or nanoparticle permeability to the in vivo situation in a human subject, the in vitro experimental system needs to realistically capture the central aspects of the mentioned barriers. Therefore, characteristics of common in vitro cell culture systems are discussed and compared to those of human intestinal tissues. Attempts to use the cell and tissue models for in vitro-in vivo extrapolation are reviewed. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

Host-microbiota interactions within the fish intestinal ecosystem.

Science.gov (United States)

Pérez, T; Balcázar, J L; Ruiz-Zarzuela, I; Halaihel, N; Vendrell, D; de Blas, I; Múzquiz, J L

2010-07-01

Teleost fish are in direct contact with the aquatic environment, and are therefore in continual contact with a complex and dynamic microbiota, some of which may have implications for health. Mucosal surfaces represent the main sites in which environmental antigens and intestinal microbiota interact with the host. Thus, the gut-associated lymphoid tissues (GALT) must develop mechanisms to discriminate between pathogenic and commensal microorganisms. Colonization of intestinal mucosal surfaces with a normal microbiota has a positive effect on immune regulatory functions of the gut, and disturbance in these immune regulatory functions by an imbalanced microbiota may contribute to the development of diseases. Significant attention has therefore been recently focused on the role of probiotics in the induction or restoration of a disturbed microbiota to its normal beneficial composition. Given this, this article explores the fascinating relationship between the fish immune system and the bacteria that are present in its intestinal microbiota, focusing on the bacterial effect on the development of certain immune responses.

Effect of an inhibitor of noradrenaline uptake, desipramine, on cell proliferation in the intestinal crypt epithelium.

Science.gov (United States)

Tutton, P J; Barkla, D H

1989-01-01

The intestinal mucosa receives an adrenergic innervation for which there is no commonly accepted function. However, in recent years, cell kinetic studies have raised the possibility that this innervation may be an important regulator of crypt cell proliferation. The effects of noradrenaline released from adrenergic nerves is terminated principally by re-uptake of the amine into the nerve and this process can be inhibited by the antidepressant drug, desipramine. In this report desipramine is shown to accelerate crypt cell proliferation in intact, but not in chemically sympathectomized rats, thus adding support to the notion that regulation of crypt cell division is an important function of the sympathetic nervous system.

In vitro characterization of cadmium transport along the gastro-intestinal tract of freshwater rainbow trout (Oncorhynchus mykiss)

Energy Technology Data Exchange (ETDEWEB)

Klinck, Joel S., E-mail: klinckjs@mcmaster.ca [Department of Biology, McMaster University, Hamilton, Ontario, L8S 4K1 (Canada); Wood, Chris M. [Department of Biology, McMaster University, Hamilton, Ontario, L8S 4K1 (Canada)

2011-03-15

An in vitro gut sac technique was used to examine the mechanism(s) of cadmium (Cd) uptake along the gastro-intestinal tract (GIT) of rainbow trout (Oncorhynchus mykiss). The spatial distribution of Cd between three compartments (mucus-binding, mucosal epithelium, and transport into blood space) was determined using a modified Cortland saline containing 50 {mu}M Cd (as CdCl{sub 2}) labeled with {sup 109}Cd radiotracer. Taking into account total surface areas, the order of relative importance for total Cd uptake rate was: posterior intestine > anterior intestine > stomach > mid intestine. Cd transport was not inhibited by experimentally reducing fluid transport rates by manipulation of osmotic gradients using mannitol, but was sensitive to internal luminal pressure changes, suggesting a mechanosensitive pathway. Q{sub 10} values (1, 11, and 19 {sup o}C) indicated a facilitated transport of Cd in the anterior- and mid-intestine. The effects of 10 mM Ca on the kinetics of Cd uptake suggest the presence of a common uptake pathway for Cd and Ca in the stomach, anterior-, and mid-intestine. Further evidence of a shared route of entry was found using three Ca channel blockers, lanthanum, verapamil, and nifedipine: both voltage-insensitive and voltage-sensitive Ca channels appear to be present in either some, or all portions of the GIT. Elevated Fe (500 {mu}M), Mg (50 mM), and Zn (500 {mu}M) showed varying degrees of inhibition of Cd transport depending on the compartment and segment of the GIT. Overall it appears that there are multiple sites, and mechanisms, of Cd uptake along the GIT of rainbow trout.

A comparison of mode of attachment and histopathogenicity of four tapeworm species representing two orders infecting the spiral intestine of the nurse shark, Ginglymostoma cirratum.

Science.gov (United States)

Borucinska, J; Caira, J N

1993-04-01

This study was undertaken to compare 2 species of Tetraphyllidea and 2 species of Trypanorhyncha with regard to the relationship between attachment structure morphology, mode of attachment, and tapeworm size, to damage at the sites of attachment in the Atlantic nurse shark, Ginglymostoma cirratum. Regions of the spiral intestine with worms attached were removed from 8 nurse sharks and sectioned according to conventional techniques. Sections of 5-50 specimens of each tapeworm species were examined. Regions of the spiral intestine devoid of worms were processed for characterization of the normal mucosa. The normal mucosa was found to consist of a folded surface covered with round-to-oval primary mucosal crypts. In the first 7 or 8 chambers of the spiral intestine the mucosal surface was thrown into secondary folds, forming ridges and secondary crypts. The primary mucosal crypts were lined with a single layer of columnar epithelium resting on a basement membrane. A highly cellular lamina propria and submucosa were found between the crypts and the muscularis mucosa. The small tetraphyllidean Pedibothrium brevispine was found with its scolex lying within the primary mucosal crypts with its hooks embedded in the basement membrane. Epithelial denudation was evident. The large tetraphyllidean Pedibothrium globicephalum was found with its bothridia engulfing large portions of the mucosa and its hooks embedded into the lamina propria. It was associated with moderate to severe mucosal necrosis. The small trypanorhynch Prochristianella tenuispine was found lying between the mucosal ridges in the secondary crypts with its tentacles either penetrating the epithelium, or occasionally, the lamina propria.(ABSTRACT TRUNCATED AT 250 WORDS)

In vitro characterization of cadmium and zinc uptake via the gastro-intestinal tract of the rainbow trout (Oncorhynchus mykiss): Interactive effects and the influence of calcium

Energy Technology Data Exchange (ETDEWEB)

Ojo, Adeola A. [Department of Biology, McMaster University, 1280 Main Street West, Hamilton, Ontario, L8S 4K1 (Canada)], E-mail: adeolaojo25@yahoo.com; Wood, Chris M. [Department of Biology, McMaster University, 1280 Main Street West, Hamilton, Ontario, L8S 4K1 (Canada)], E-mail: woodcm@mcmaster.ca

2008-08-11

An in vitro gut sac technique was employed to study whether Cd and Zn uptake mechanisms in the gastro-intestinal tract of the rainbow trout are similar to those at the gills, where both metals are taken up via the Ca transport pathway. Metal accumulation in surface mucus, in the mucosal epithelium, and transport into the blood space were assayed using radiolabelled Cd or Zn concentrations of 50 {mu}mol L{sup -1} in the luminal (internal) saline. Elevated luminal Ca (10 or 100 mmol L{sup -1}versus 1 mmol L{sup -1}) reduced Cd uptake into all three phases by approximately 60% in the stomach, but had no effect in the anterior, mid, or posterior intestine. This finding is in accordance with recent in vivo evidence that Ca is taken up mainly via the stomach, and that high [Ca] diets inhibit Cd accumulation from the food specifically in this section of the tract. In contrast, 10 mmol L{sup -1} luminal Ca had no effect on Zn transport in any section, whereas 100 mmol L{sup -1} Ca stimulated Zn uptake, by approximately threefold, into all three phases in the stomach only. There was no influence of elevated luminal Zn (10 mmol L{sup -1}) on Cd uptake in the stomach or anterior intestine, or of high Cd (10 mmol L{sup -1}) on Zn uptake in these sections. However, high [Zn] stimulated Cd transport into the blood space but inhibited accumulation in the mucosal epithelium and/or mucus-binding in the mid and posterior intestine, whereas high [Cd] exerted a reciprocal effect in the mid-intestine only. We conclude that Cd uptake occurs via an important Ca-sensitive mechanism in the stomach which is different from that at the gills, while Cd transport mechanisms in the intestine are not directly Ca-sensitive. Zn uptake does not appear to involve Ca uptake pathways, in contrast to the gills. These results are discussed in the context of other possible Cd and Zn transport pathways, and the emerging role of the stomach as an organ of divalent metal uptake.

Acrolein Disrupts Tight Junction Proteins and Causes Endoplasmic Reticulum Stress-Mediated Epithelial Cell Death Leading to Intestinal Barrier Dysfunction and Permeability.

Science.gov (United States)

Chen, Wei-Yang; Wang, Min; Zhang, Jingwen; Barve, Shirish S; McClain, Craig J; Joshi-Barve, Swati

2017-12-01

Increasing evidence suggests that environmental and dietary factors can affect intestinal epithelial integrity leading to gut permeability and bacterial translocation. Intestinal barrier dysfunction is a pathogenic process associated with many chronic disorders. Acrolein is an environmental and dietary pollutant and a lipid-derived endogenous metabolite. The impact of acrolein on the intestine has not been investigated before and is evaluated in this study, both in vitro and in vivo. Our data demonstrate that oral acrolein exposure in mice caused damage to the intestinal epithelial barrier, resulting in increased permeability and subsequently translocation of bacterial endotoxin-lipopolysaccharide into the blood. Similar results were seen in vitro using established Caco-2 cell monolayers wherein acrolein decreased barrier function and increased permeability. Acrolein also caused the down-regulation and/or redistribution of three representative tight junction proteins (ie, zonula occludens-1, Occludin, Claudin-1) that critically regulate epithelial paracellular permeability. In addition, acrolein induced endoplasmic reticulum stress-mediated death of epithelial cells, which is an important mechanism contributing to intestinal barrier damage/dysfunction, and gut permeability. Overall, we demonstrate that exposure to acrolein affects the intestinal epithelium by decrease/redistribution of tight junction proteins and endoplasmic reticulum stress-mediated epithelial cell death, thereby resulting in loss of barrier integrity and function. Our findings highlight the adverse consequences of environmental and dietary pollutants on intestinal barrier integrity/function with relevance to gut permeability and the development of disease. Copyright © 2017 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

The intestinal barrier function and its involvement in digestive disease

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Eloísa Salvo-Romero

2015-11-01

Full Text Available The gastrointestinal mucosal surface is lined with epithelial cells representing an effective barrier made up with intercellular junctions that separate the inner and the outer environments, and block the passage of potentially harmful substances. However, epithelial cells are also responsible for the absorption of nutrients and electrolytes, hence a semipermeable barrier is required that selectively allows a number of substances in while keeping others out. To this end, the intestine developed the "intestinal barrier function", a defensive system involving various elements, both intra- and extracellular, that work in a coordinated way to impede the passage of antigens, toxins, and microbial byproducts, and simultaneously preserves the correct development of the epithelial barrier, the immune system, and the acquisition of tolerance against dietary antigens and the intestinal microbiota. Disturbances in the mechanisms of the barrier function favor the development of exaggerated immune responses; while exact implications remain unknown, changes in intestinal barrier function have been associated with the development of inflammatory conditions in the gastrointestinal tract. This review details de various elements of the intestinal barrier function, and the key molecular and cellular changes described for gastrointestinal diseases associated with dysfunction in this defensive mechanism.

Disruption of the epithelial barrier during intestinal inflammation: Quest for new molecules and mechanisms.

Science.gov (United States)

Lechuga, Susana; Ivanov, Andrei I

2017-07-01

The intestinal epithelium forms a key protective barrier that separates internal organs from the harmful environment of the gut lumen. Increased permeability of the gut barrier is a common manifestation of different inflammatory disorders contributing to the severity of disease. Barrier permeability is controlled by epithelial adherens junctions and tight junctions. Junctional assembly and integrity depend on fundamental homeostatic processes such as cell differentiation, rearrangements of the cytoskeleton, and vesicle trafficking. Alterations of intestinal epithelial homeostasis during mucosal inflammation may impair structure and remodeling of apical junctions, resulting in increased permeability of the gut barrier. In this review, we summarize recent advances in our understanding of how altered epithelial homeostasis affects the structure and function of adherens junctions and tight junctions in the inflamed gut. Specifically, we focus on the transcription reprogramming of the cell, alterations in the actin cytoskeleton, and junctional endocytosis and exocytosis. We pay special attention to knockout mouse model studies and discuss the relevance of these mechanisms to human gastrointestinal disorders. Copyright © 2017 Elsevier B.V. All rights reserved.

Hes1-deficient mice show precocious differentiation of Paneth cells in the small intestine

International Nuclear Information System (INIS)

Suzuki, Katsumasa; Fukui, Hirokazu; Kayahara, Takahisa; Sawada, Mitsutaka; Seno, Hiroshi; Hiai, Hiroshi; Kageyama, Ryoichiro; Okano, Hideyuki; Chiba, Tsutomu

2005-01-01

We have previously shown that Hes1 is expressed both in putative epithelial stem cells just above Paneth cells and in the crypt base columnar cells between Paneth cells, while Hes1 is completely absent in Paneth cells. This study was undertaken to clarify the role of Hes1 in Paneth cell differentiation, using Hes1-knockout (KO) newborn (P0) mice. Electron microscopy revealed premature appearance of distinct cells containing cytoplasmic granules in the intervillous region in Hes1-KO P0 mice, whereas those cells were absent in wild-type (WT) P0 mice. In Hes1-KO P0 mice, the gene expressions of cryptdins, exclusively present in Paneth cells, were all enhanced compared with WT P0 mice. Immunohistochemistry demonstrated increased number of both lysozyme-positive and cryptdin-4-positive cells in the small intestinal epithelium of Hes1-KO P0 mice as compared to WT P0 mice. Thus, Hes1 appears to have an inhibitory role in Paneth cell differentiation in the small intestine

Cultivated Oral Mucosa Epithelium in Ocular Surface Reconstruction in Aniridia Patients

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Dariusz Dobrowolski

2015-01-01

Full Text Available Purpose. Efficacy of cultivated oral mucosa epithelial transplantation (COMET procedure in corneal epithelium restoration of aniridia patients. Methods. Study subjects were aniridia patients (13 patients; 17 eyes with irregular, vascular conjunctival pannus involving visual axis who underwent autologous transplantation of cultivated epithelium. For the procedure oral mucosa epithelial cells were obtained from buccal mucosa with further enzymatic treatment. Suspension of single cells was seeded on previously prepared denuded amniotic membrane. Cultures were carried on culture dishes inserts in the presence of the inactivated with Mitomycin C monolayer of 3T3 fibroblasts. Cultures were carried for seven days. Stratified oral mucosa epithelium with its amniotic membrane carrier was transplanted on the surgically denuded corneal surface of aniridia patients with total or subtotal limbal stem cell deficiency. Outcome Measures. Corneal surface, epithelial regularity, and visual acuity improvement were evaluated. Results. At the end of the observation period, 76.4% of the eyes had regular transparent epithelium and 23.5% had developed epithelial defects or central corneal haze; in 88.2% of cases visual acuity had increased. VA range was from HM 0.05 before the surgery to HM up to 0.1 after surgery. Conclusion. Application of cultivated oral mucosa epithelium restores regular epithelium on the corneal surface with moderate improvement in quality of vision.

File list: InP.Oth.05.AllAg.Olfactory_epithelium [Chip-atlas[Archive

Lifescience Database Archive (English)

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File list: InP.Oth.50.AllAg.Olfactory_epithelium [Chip-atlas[Archive

Lifescience Database Archive (English)

Full Text Available InP.Oth.50.AllAg.Olfactory_epithelium mm9 Input control Others Olfactory epithelium... SRX112965,SRX185883,SRX143806,SRX378545,SRX378544 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/InP.Oth.50.AllAg.Olfactory_epithelium.bed ...

File list: InP.Oth.20.AllAg.Olfactory_epithelium [Chip-atlas[Archive

Lifescience Database Archive (English)

Full Text Available InP.Oth.20.AllAg.Olfactory_epithelium mm9 Input control Others Olfactory epithelium... SRX112965,SRX185883,SRX143806,SRX378545,SRX378544 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/InP.Oth.20.AllAg.Olfactory_epithelium.bed ...

File list: InP.Oth.10.AllAg.Olfactory_epithelium [Chip-atlas[Archive

Lifescience Database Archive (English)

Full Text Available InP.Oth.10.AllAg.Olfactory_epithelium mm9 Input control Others Olfactory epithelium... SRX112965,SRX185883,SRX143806,SRX378545,SRX378544 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/InP.Oth.10.AllAg.Olfactory_epithelium.bed ...

Transepithelial transfer of phenanthrene, but not of benzo[a]pyrene, is inhibited by fatty acids in the proximal intestine of rainbow trout (Oncorhynchus mykiss).

Science.gov (United States)

de Gelder, Stefan; Sundh, Henrik; Pelgrim, Thamar N M; Rasinger, Josef D; van Daal, Lotte; Flik, Gert; Berntssen, Marc H G; Klaren, Peter H M

2018-01-01

The inclusion of vegetable oils in aquafeeds introduces contaminating polycyclic aromatic hydrocarbons (PAHs) in salmonids. Since lipophilic PAHs solubilize in micelles composed of lipids, bile salts and fatty acids, dietary lipid composition can alter intestinal transepithelial PAH transfer. We studied the uptake of two PAHs, viz. benzo[a]pyrene (BaP) and phenanthrene (PHE), in rainbow trout (Oncorhynchus mykiss) intestine. We also investigated the effects of two fatty acids, viz. fish oil-derived eicosapentaenoic acid (EPA, 20:5n-3) and vegetable oil-derived oleic acid (18:1n-9) on intestinal uptake. Radiolabeled PAHs were solubilized in micelles composed of tritiated EPA and oleic acid, respectively, and administrated to intestinal segments mounted in Ussing chambers. In the absence of micelles, PHE accumulation was two times higher than BaP in the mucosal and serosal layers of proximal and distal intestine. Administration of PHE in micelles composed of oleic acid resulted in a 50% lower accumulation of PHE in the mucosal layers of the proximal intestine compared to EPA-composed micelles. Accumulation of EPA and oleic acid in the proximal intestinal mucosa correlated negatively with the transepithelial transfer of these fatty acids across the proximal intestinal epithelium. Transepithelial PHE transfer across the proximal intestine was reduced by 30% in co-exposure with EPA-composed micelles compared to 80% with oleic acid micelles. BaP was not transferred across the intestine. We conclude that the lipid composition of an aquafeed is an important determinant of PAH bioavailability. Therefore, lipid composition should be an important consideration in choosing vegetable oils as alternatives for fish oil in aquafeeds. Copyright © 2017 Elsevier Inc. All rights reserved.

Regional variations of cell surface carbohydrates in human oral stratified epithelium

DEFF Research Database (Denmark)

Vedtofte, P; Dabelsteen, Erik; Hakomori, S

1984-01-01

The distribution of blood group carbohydrate chains with antigen A, B, H type 2 chain (A and B precursor), and N-acetyllactosamine (H type 2 precursor) specificity was studied in human oral epithelium from different anatomical regions. These represented various epithelial differentiation patterns...... epithelium from nine blood group A, two blood group B, and nine blood group O individuals. The blood group carbohydrate chains were examined in tissue sections by immunofluorescence microscopy. The A and B blood group antigens were detected by human blood group sera, and antigen H type 2 chains and N...... antigen H type 2 chains in metaplastically keratinized buccal epithelium was found to differ significantly from that seen in normal non-keratinized buccal epithelium. The regional variations demonstrated in cell surface carbohydrates are suggested to reflect differences in tissue differentiation....

Interkinetic nuclear migration in the mouse embryonic ureteric epithelium: Possible implication for congenital anomalies of the kidney and urinary tract.

Science.gov (United States)

Motoya, Tomoyuki; Ogawa, Noriko; Nitta, Tetsuya; Rafiq, Ashiq Mahmood; Jahan, Esrat; Furuya, Motohide; Matsumoto, Akihiro; Udagawa, Jun; Otani, Hiroki

2016-05-01

Interkinetic nuclear migration (INM) is a phenomenon in which progenitor cell nuclei migrate along the apico-basal axis of the pseudostratified epithelium, which is characterized by the presence of apical primary cilia, in synchrony with the cell cycle in a manner of apical mitosis. INM is suggested to regulate not only stem/progenitor cell proliferation/differentiation but also organ size and shape. INM has been reported in epithelia of both ectoderm and endoderm origin. We examined whether INM exists in the mesoderm-derived ureteric epithelium. At embryonic day (E) 11.5, E12.5 and E13.5, C57BL/6J mouse dams were injected with 5-bromo-2'-deoxyuridine (BrdU) and embryos were killed 1, 2, 4, 6, 8, 10 and 12 h later. We immunostained transverse sections of the ureter for BrdU, and measured the position of BrdU (+) nuclei in the ureteric epithelia along the apico-basal axis at each time point. We analyzed the distribution patterns of BrdU (+) nuclei in histograms using the multidimensional scaling. Changes in the nucleus distribution patterns suggested nucleus movement characteristic of INM in the ureteric epithelia, and the mode of INM varied throughout the ureter development. While apical primary cilia are related with INM by providing a centrosome for the apical mitosis, congenital anomalies of the kidney and urinary tract (CAKUT) include syndromes linked to primary ciliary dysfunction affecting epithelial tubular organs such as kidney, ureter, and brain. The present study showed that INM exists in the ureteric epithelium and suggests that INM may be related with the CAKUT etiology via primary ciliary protein function. © 2015 Japanese Teratology Society.

Cyanidin-3-O-Glucoside Modulates the In Vitro Inflammatory Crosstalk between Intestinal Epithelial and Endothelial Cells

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Daniela Ferrari

2017-01-01

Full Text Available Intestinal epithelium represents a protective physical barrier and actively contributes to the mucosal immune system. Polarized basolateral intestinal secretion of inflammatory mediators, followed by activation of NF-κB signaling and inflammatory pathways in endothelial cells, efficiently triggers extravasation of neutrophils from the vasculature, therefore contributing to the development and maintenance of intestinal inflammation. Proper regulation of NF-κB activation at the epithelial interface is crucial for the maintenance of physiological tissue homeostasis. Many papers reported that anthocyanins, a group of compounds belonging to flavonoids, possess anti-inflammatory effects and modulate NF-κB activity. In this study, by using a coculture in vitro system, we aimed to evaluate the effects of TNF-α-stimulated intestinal cells on endothelial cells activation, as well as the protective effects of cyanidin-3-glucoside (C3G. In this model, TNF-α induced nuclear translocation of NF-κB and TNF-α and IL-8 gene expression in Caco-2 cells, whereas C3G pretreatment dose-dependently reduced these effects. Furthermore, TNF-α-stimulated Caco-2 cells induced endothelial cells activation with increased E-selectin and VCAM-1 mRNA, leukocyte adhesion, and NF-κB levels in HUVECs, which were inhibited by C3G. We demonstrated that selective inhibition of the NF-κB pathway in epithelial cells represents the main mechanism by which C3G exerts these protective effects. Thus, anthocyanins could contribute to the management of chronic gut inflammatory diseases.

Biogenic amines as regulators of the proliferative activity of normal and neoplastic intestinal epithelial cells (review).

Science.gov (United States)

Tutton, P J; Barkla, D H

1987-01-01

The role of extracellular amines such as noradrenaline and serotonin and their interaction with cyclic nucleotides and intracellular polyamines in the regulation of intestinal epithelial cell proliferation is reviewed with particular reference to the differences between normal and neoplastic cells. In respect to the normal epithelium of the small intestine there is a strong case to support the notion that cell proliferation is controlled by, amongst other things, sympathetic nerves. In colonic carcinomas, antagonists for certain serotonin receptors, for histamine H2 receptors and for dopamine D2 receptors inhibit both cell division and tumour growth. Because of the reproducible variations between tumour lines in the response to these antagonists, this inhibition appears to be due to a direct effect on the tumour cells rather than an indirect effect via the tumour host or stroma. This conclusion is supported by the cytocidal effects of toxic congeners of serotonin on the tumour cells. The most salient difference between the amine responses of normal and neoplastic cells relates to the issue of amine uptake. Proliferation of crypt cells is promoted by amine uptake inhibitors, presumably because they block amine re-uptake by the amine secreting cells--sympathetic neurones and enteroendocrine cells. However, tumour cell proliferation is strongly inhibited by amine uptake inhibitors, suggesting that neoplastic cells can, and need to take up the amine before being stimulated by it. Recent revelations in the field of oncogenes also support an important association between amines, cyclic nucleotides and cell division. The ras oncogenes code for a protein that is a member of a family of molecules which relay information from extracellular regulators, such as biogenic amines, to the intracellular regulators, including cyclic nucleotides. Evidence is presented suggesting that enteroendocrine cells, enterocytes, carcinoid tumour cells and adenocarcinoma cells all have the same

Cytotoxicity, Intestinal Transport, and Bioavailability of Dispersible Iron and Zinc Supplements

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Jae-Min Oh

2017-04-01

Full Text Available Iron or zinc deficiency is one of the most important nutritional disorders which causes health problem. However, food fortification with minerals often induces unacceptable organoleptic changes during preparation process and storage, has low bioavailability and solubility, and is expensive. Nanotechnology surface modification to obtain novel characteristics can be a useful tool to overcome these problems. In this study, the efficacy and potential toxicity of dispersible Fe or Zn supplement coated in dextrin and glycerides (SunActive FeTM and SunActive ZnTM were evaluated in terms of cytotoxicity, intestinal transport, and bioavailability, as compared with each counterpart without coating, ferric pyrophosphate (FePP and zinc oxide (ZnO nanoparticles (NPs, respectively. The results demonstrate that the cytotoxicity of FePP was not significantly affected by surface modification (SunActive FeTM, while SunActive ZnTM was more cytotoxic than ZnO-NPs. Cellular uptake and intestinal transport efficiency of SunActive FeTM were significantly higher than those of its counterpart material, which was in good agreement with enhanced oral absorption efficacy after a single-dose oral administration to rats. These results seem to be related to dissolution, particle dispersibility, and coating stability of materials depending on suspending media. Both SunActiveTM products and their counterpart materials were determined to be primarily transported by microfold (M cells through the intestinal epithelium. It was, therefore, concluded that surface modification of food fortification will be a useful strategy to enhance oral absorption efficiency at safe levels.

In vitro analysis of the bioavailability of six metals via the gastro-intestinal tract of the rainbow trout (Oncorhynchus mykiss)

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Ojo, Adeola A. [Department of Biology, McMaster University, 1280 Main Street West, Hamilton, Ontario, L8S 4K1 (Canada)]. E-mail: abosede_07@hotmail.com; Wood, Chris M. [Department of Biology, McMaster University, 1280 Main Street West, Hamilton, Ontario, L8S 4K1 (Canada)]. E-mail: woodcm@mcmaster.ca

2007-06-05

An in vitro gut sac technique was used to compare the uptake rates of essential (copper, zinc and nickel) and non-essential metals (silver, cadmium and lead) at 50 {mu}mol L{sup -1} each (a typical nutritive level in solution in chyme) in the luminal saline in four sections of the gastro-intestinal tract (stomach, anterior, mid and posterior intestines) of the freshwater rainbow trout. Cu, Zn, Cd and Ag exhibited similar regional patterns: on an area-specific basis, uptake rates for these metals were highest in the anterior intestine, lowest in the stomach, and approximately equal in the mid and posterior intestinal segments. When these rates were converted to a whole animal basis, the predominance of the anterior intestine increased because of its greater area, while the contribution of the stomach rose slightly to approach those of the mid and posterior intestines. However, for Pb and Ni, area-specific and whole organism transport rates were greatest in the mid (Pb) and posterior (Ni) intestines. Surprisingly, total transport rates did not differ appreciably among the essential and non-essential metals, varying only from 0.025 (Ag) to 0.050 nmol g{sup -1} h{sup -1} (Ni), suggesting that a single rate constant can be applied for risk assessment purposes. These rates were generally comparable to previously reported uptake rates from waterborne exposures conducted at concentrations 1-4 orders of magnitude lower, indicating that both routes are likely important, and that gut transporters operate with much lower affinity than gill transporters. Except for Ni, more metal was bound to mucus and/or trapped in the mucosal epithelium than was transported into the blood space in every compartment except the anterior intestine, where net transport predominated. Overall, mucus binding was a significant predictor of net transport rate for every metal except Cd, and the strongest relationship was seen for Pb.

Activation of intestinal epithelial Stat3 orchestrates tissue defense during gastrointestinal infection.

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Nadine Wittkopf

Full Text Available Gastrointestinal infections with EHEC and EPEC are responsible for outbreaks of diarrheal diseases and represent a global health problem. Innate first-line-defense mechanisms such as production of mucus and antimicrobial peptides by intestinal epithelial cells are of utmost importance for host control of gastrointestinal infections. For the first time, we directly demonstrate a critical role for Stat3 activation in intestinal epithelial cells upon infection of mice with Citrobacter rodentium - a murine pathogen that mimics human infections with attaching and effacing Escherichia coli. C. rodentium induced transcription of IL-6 and IL-22 in gut samples of mice and was associated with activation of the transcription factor Stat3 in intestinal epithelial cells. C. rodentium infection induced expression of several antimicrobial peptides such as RegIIIγ and Pla2g2a in the intestine which was critically dependent on Stat3 activation. Consequently, mice with specific deletion of Stat3 in intestinal epithelial cells showed increased susceptibility to C. rodentium infection as indicated by high bacterial load, severe gut inflammation, pronounced intestinal epithelial cell death and dissemination of bacteria to distant organs. Together, our data implicate an essential role for Stat3 activation in intestinal epithelial cells during C. rodentium infection. Stat3 concerts the host response to bacterial infection by controlling bacterial growth and suppression of apoptosis to maintain intestinal epithelial barrier function.

A prospective randomized controlled study of erythromycin on gastric and small intestinal distention: Implications for MR enterography

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Bharucha, Adil E., E-mail: bharucha.adil@mayo.edu [Clinical Enteric Neuroscience Translational and Epidemiological Research (C.E.N.T.E.R.) Program, Division of Gastroenterology and Hepatology, College of Medicine, Mayo Clinic, 200 First St. S.W., Rochester, MN 55905 (United States); Fidler, Jeff L., E-mail: fidler.jeff@mayo.edu [Department of Radiology, College of Medicine, Mayo Clinic, 200 First St. S.W., Rochester, MN 55905 (United States); Huprich, James E., E-mail: huprich@mayo.edu [Department of Radiology, College of Medicine, Mayo Clinic, 200 First St. S.W., Rochester, MN 55905 (United States); Ratuapli, Shiva K., E-mail: ratuapli.shiva@mayo.edu [Clinical Enteric Neuroscience Translational and Epidemiological Research (C.E.N.T.E.R.) Program, Division of Gastroenterology and Hepatology, College of Medicine, Mayo Clinic, 200 First St. S.W., Rochester, MN 55905 (United States); Holmes, David R., E-mail: holmes.david3@mayo.edu [Biomedical Imaging Resource, College of Medicine, Mayo Clinic, 200 First St. S.W., Rochester, MN 55905 (United States); Riederer, Stephen J., E-mail: riederer@mayo.edu [MR Research Laboratory, College of Medicine, Mayo Clinic, 200 First St. S.W., Rochester, MN 55905 (United States); Zinsmeister, Alan R., E-mail: zinsmeis@mayo.edu [Division of Biomedical Statistics and Informatics, College of Medicine, Mayo Clinic, 200 First St. S.W., Rochester, MN 55905 (United States)

2014-11-15

Highlights: • Suboptimal small intestinal distention limits jejunal visualization during MRI. • In this controlled study, erythromycin increased gastric emptying measured with MRI. • However, effects on small intestinal dimensions were variable. - Abstract: Objectives: To assess if erythromycin increases gastric emptying and hence improves small intestinal distention during MR enterography. Methods: Gastric, small intestinal, and large intestinal volumes were assessed with MR after neutral oral contrast (1350 ml in 45 min) and balanced randomization to erythromycin (200 mg i.v., age 31 ± 3y, 13 females), or placebo (37 ± 3y, 13 females) in 40 healthy asymptomatic volunteers. Fat-suppressed T2-weighted MR images of the abdomen were acquired on a 1.5 T magnet at standard delay times for enterography. Gastric, small, and large intestinal volumes were measured by specialized software. In addition, two radiologists manually measured diameters and percentage distention of jejunal and ileal loops. Treatment effects were evaluated by an ITT analysis based on ANCOVA models. Results: All subjects tolerated erythromycin. MRI scans of the stomach and intestine were obtained at 62 ± 2 (mean ± SEM) and 74 ± 2 min respectively after starting oral contrast. Gastric volumes were lower (P < 0.0001) after erythromycin (260 ± 49 ml) than placebo (688 ± 63 ml) but jejunal, ileal, and colonic volumes were not significantly different. However, maximum (76–100%) jejunal distention was more frequently observed (P = 0.03) after erythromycin (8/20 subjects [40%]) than placebo (2/20 subjects [10%]). The diameter of a representative ileal loop was greater (P = 0.001) after erythromycin (18.8 ± 4.3 mm) than placebo (17.3 ± 2.8 mm) infusion. Conclusions: After ingestion of oral contrast, erythromycin accelerated gastric emptying but effects on small intestinal dimensions were variable. In balance, erythromycin did not substantially enhance small intestinal distention during

A prospective randomized controlled study of erythromycin on gastric and small intestinal distention: Implications for MR enterography

International Nuclear Information System (INIS)

Bharucha, Adil E.; Fidler, Jeff L.; Huprich, James E.; Ratuapli, Shiva K.; Holmes, David R.; Riederer, Stephen J.; Zinsmeister, Alan R.

2014-01-01

Highlights: • Suboptimal small intestinal distention limits jejunal visualization during MRI. • In this controlled study, erythromycin increased gastric emptying measured with MRI. • However, effects on small intestinal dimensions were variable. - Abstract: Objectives: To assess if erythromycin increases gastric emptying and hence improves small intestinal distention during MR enterography. Methods: Gastric, small intestinal, and large intestinal volumes were assessed with MR after neutral oral contrast (1350 ml in 45 min) and balanced randomization to erythromycin (200 mg i.v., age 31 ± 3y, 13 females), or placebo (37 ± 3y, 13 females) in 40 healthy asymptomatic volunteers. Fat-suppressed T2-weighted MR images of the abdomen were acquired on a 1.5 T magnet at standard delay times for enterography. Gastric, small, and large intestinal volumes were measured by specialized software. In addition, two radiologists manually measured diameters and percentage distention of jejunal and ileal loops. Treatment effects were evaluated by an ITT analysis based on ANCOVA models. Results: All subjects tolerated erythromycin. MRI scans of the stomach and intestine were obtained at 62 ± 2 (mean ± SEM) and 74 ± 2 min respectively after starting oral contrast. Gastric volumes were lower (P < 0.0001) after erythromycin (260 ± 49 ml) than placebo (688 ± 63 ml) but jejunal, ileal, and colonic volumes were not significantly different. However, maximum (76–100%) jejunal distention was more frequently observed (P = 0.03) after erythromycin (8/20 subjects [40%]) than placebo (2/20 subjects [10%]). The diameter of a representative ileal loop was greater (P = 0.001) after erythromycin (18.8 ± 4.3 mm) than placebo (17.3 ± 2.8 mm) infusion. Conclusions: After ingestion of oral contrast, erythromycin accelerated gastric emptying but effects on small intestinal dimensions were variable. In balance, erythromycin did not substantially enhance small intestinal distention during

Curcumin Attenuates Gamma Radiation Induced Intestinal Damage in Rats

International Nuclear Information System (INIS)

EI-Tahawy, N.A.

2009-01-01

Small Intestine exhibits numerous morphological and functional alterations during radiation exposure. Oxidative stress, a factor implicated in the intestinal injury may contribute towards some of these alterations. The present work was designed to evaluate the efficacy of curcumin, a yellow pigment of turmeric on y-radiation-induced oxidative damage in the small intestine by measuring alterations in the level of thiobarbituric acid reactive substances (TSARS), serotonin metabolism, catecholamine levels, and monoamine oxidase (MAO) activity in parallel to changes in the architecture of intestinal tissues. In addition, monoamine level, MAO activity and TSARS level were determined in the serum. Curcumin was supplemented orally via gavages, to rats at a dose of (45 mg/ Kg body wt/ day) for 2 weeks pre-irradiation and the last supplementation was 30 min pre exposure to 6.5 Gy gamma radiations (applied as one shot dose). Animals were sacrificed on the 7th day after irradiation. The results demonstrated that, whole body exposure of rats to ionizing radiation has induced oxidative damage in small intestine obvious by significant increases of TSARS content, MAO activity and 5-hydroxy indole acetic acid (5-HIAA) and by significant decreases of serotonin (5-HT), dopamine (DA), norepinephrine (NE) and epinephrine (EPI) levels. In parallel histopathological studies of the small intestine of irradiated rats through light microscopic showed significant decrease in the number of villi, villus height, mixed sub mucosa layer with more fibres and fibroblasts. Intestinal damage was in parallel to significant alterations of serum MAO activity, TBARS, 5-HT, DA, NE and EPI levels. Administration of curcumin before irradiation has significantly improved the levels of monoamines in small intestine and serum of irradiated rats, which was associated with significant amelioration in MAO activity and TBARS contents

Influence of ionizing radiation, photoperiod, and environmental temperature on cell proliferation in the intestinal epithelium of the rough-skinned newt (Taricha granulosa)

International Nuclear Information System (INIS)

Filipy, R.E.

1977-01-01

Kinetics of cell division in the intestinal epithelial proliferative cells (cell nests) of the rough-skinned newt, Taricha granulosa, were studied using tritiated thymidine autoradiography and the mitotic arresting properties of colcemid. Percent labeled mitoses (PLM) curves were drawn from the autoradiographic data from two separate experiments in which the newts were maintained at room temperature (22 to 23 0 C). In those experiments, groups of newts were intraperitoneally injected with tritiated thymidine at times ranging between 5 and 58 hours before they were killed. Each newt in both experiments was intraperitoneally injected with colcemid five hours before it was killed. Data from both experiments were very similar and the PLM curves were used to estimate cell cycle phase durations in the cell nests. The DNA synthetic phase was estimated to be 41 hours long and the sum of the G 2 phase duration and one-half the duration of mitosis was approximately seven hours. The duration of the entire cell cycle was considered to be longer than 100 hours and the duration of the G 1 phase longer than 50 hours. Whole-body exposure of newts to 100 R x irradiation essentially stopped mitotic activity in the intestinal cell nests for 32 hours and exposure to 200 R stopped the mitotic activity for 56 hours. Recovery of mitotic activity in the cell nests was in evidence in data from both groups of animals after both those time periods. Whole-body exposure of newts to 1000 R x irradiation severely depressed mitotic activity in the intestinal cell nests for at least 78 hours and resulted in diminished numbers of the cell nests although the mature cells of the intestinal cells appeared to be relatively radioresistant

Colon in acute intestinal infection.

Science.gov (United States)

Guarino, Alfredo; Buccigrossi, Vittoria; Armellino, Carla

2009-04-01

The colon is actively implicated in intestinal infections not only as a target of enteric pathogens and their products but also as a target organ for treatment. In the presence of diarrhea, both of osmotic and secretory nature, the colon reacts with homeostatic mechanisms to increase ion absorption. These mechanisms can be effectively exploited to decrease fluid discharge. A model of intestinal infections using rotavirus (RV) in colonic cells was set up and used to define a dual model of secretory and osmotic diarrhea in sequence. Using this model, antidiarrheal drugs were tested, namely zinc and the enkephalinase inhibitor racecadotril. Zinc was able to decrease the enterotoxic activity responsible for secretory diarrhea. It also inhibited the cytotoxic effect of RV. The mechanism of zinc was related at least in part to the activation of MAPK activity, but also a direct antiviral effect was observed. Racecadotril showed a potent and selective inhibition of active secretion, being particularly effective in the first phase of RV diarrhea. The use of drugs active at the colonic level, therefore, offers effective options to treat intestinal infections in childhood. In addition, the colon is the natural site of colonic microflora, a target of probiotic therapy, which is the first line of approach recommended by the European Society for Paediatric Gastroenterology, Hepatology and Nutrition to treat infectious diarrhea.

Intestinal fluid absorption in anadromous salmonids: importance of tight junctions and aquaporins

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Kristina eSundell

2012-09-01

Full Text Available The anadromous salmonid life cycle includes both fresh water (FW and seawater (SW stages. The parr-smolt transformation (smoltification pre–adapt the fish to SW while still in FW. The osmoregulatory organs change their mode of action from a role of preventing water inflow in FW, to absorb ions to replace water lost by osmosis in SW. During smoltification, the drinking rate increases, in the intestine the ion and fluid transport increases and is further elevated after SW entry. In SW, the intestine absorbs ions to create an inwardly directed water flow which is accomplished by increased Na+,K+-ATPase (NKA activity in the basolateral membrane, driving ion absorption via ion channels and/or co-transporters. This review will aim at discussing the expression patterns of the ion transporting proteins involved in intestinal fluid absorption in the FW stage, during smoltification and after SW entry. Of equal importance for intestinal fluid absorption as the active absorption of ions, is the permeability of the epithelium to ions and water. During the smoltification the increase in NKA activity and water uptake in SW is accompanied by decreased paracellular permeability suggesting a redirection of the fluid movement from a paracellular route in FW, to a transcellular route in SW. Increased transcellular fluid absorption could be achieved by incorporation of aquaporins (AQPs into the enterocyte membranes and/or by a change in fatty acid profile of the enterocyte lipid bilayer. An increased incorporation of unsaturated fatty acids into the membrane phospholipids will increase water permeability by enhancing the fluidity of the membrane. A second aim of the present review is therefore to discuss the presence and regulation of expression of AQPs in the enterocyte membrane as well as to discuss the profile of fatty acids present in the membrane phospholipids during different stages of the salmonid lifecycle.

Apple extract induces increased epithelial resistance and claudin 4 expression in Caco-2 cells

NARCIS (Netherlands)

Vreeburg, R.A.M.; Wezel, van E.E.; Ocana-Calahorro, F.; Mes, J.J.

2012-01-01

BACKGROUND: The small intestinal epithelium functions both to absorb nutrients, and to provide a barrier between the outside, luminal, world and the human body. One of the passageways across the intestinal epithelium is paracellular diffusion, which is controlled by the properties of tight junction

Thyroid Hormone-Induced Activation of Notch Signaling is Required for Adult Intestinal Stem Cell Development During Xenopus Laevis Metamorphosis.

Science.gov (United States)

Hasebe, Takashi; Fujimoto, Kenta; Kajita, Mitsuko; Fu, Liezhen; Shi, Yun-Bo; Ishizuya-Oka, Atsuko

2017-04-01

In Xenopus laevis intestine during metamorphosis, the larval epithelial cells are removed by apoptosis, and the adult epithelial stem (AE) cells appear concomitantly. They proliferate and differentiate to form the adult epithelium (Ep). Thyroid hormone (TH) is well established to trigger this remodeling by regulating the expression of various genes including Notch receptor. To study the role of Notch signaling, we have analyzed the expression of its components, including the ligands (DLL and Jag), receptor (Notch), and targets (Hairy), in the metamorphosing intestine by real-time reverse transcription-polymerase chain reaction and in situ hybridization or immunohistochemistry. We show that they are up-regulated during both natural and TH-induced metamorphosis in a tissue-specific manner. Particularly, Hairy1 is specifically expressed in the AE cells. Moreover, up-regulation of Hairy1 and Hairy2b by TH was prevented by treating tadpoles with a γ-secretase inhibitor (GSI), which inhibits Notch signaling. More importantly, TH-induced up-regulation of LGR5, an adult intestinal stem cell marker, was suppressed by GSI treatment. Our results suggest that Notch signaling plays a role in stem cell development by regulating the expression of Hairy genes during intestinal remodeling. Furthermore, we show with organ culture experiments that prolonged exposure of tadpole intestine to TH plus GSI leads to hyperplasia of secretory cells and reduction of absorptive cells. Our findings here thus provide evidence for evolutionarily conserved role of Notch signaling in intestinal cell fate determination but more importantly reveal, for the first time, an important role of Notch pathway in the formation of adult intestinal stem cells during vertebrate development. Stem Cells 2017;35:1028-1039. © 2016 The Authors STEM CELLS published by Wiley Periodicals, Inc. on behalf of AlphaMed Press.