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Sample records for human intestinal mucus

  1. Human intestinal mucus proteins isolated by transanal irrigation and proctosigmoidoscopy

    Directory of Open Access Journals (Sweden)

    Paola Andrea Gómez Buitrago

    2015-10-01

    Full Text Available Human intestinal mucus essentially consistsof a network of Mucin2 glycoproteinsembedded in many lower molecularweight proteins. This paper contributes tothe proteomic study of human intestinalmucus by comparing two sample collectionmethods (transanal irrigation and brushcytology during proctosigmoidoscopy andanalysis techniques (electrophoresis anddigestion in solution. The entire samplecollection and treatment process is explained,including protein extraction, digestion anddesalination and peptide characterisationusing a nanoAcquity UPLC chromatographcoupled to an HDMS spectrometer equippedwith a nanoESI source. Collecting mucus viatransanal irrigation provided a larger samplevolume and protein concentration from asingle patient. The proctosigmoidoscopysample could be analysed via digestion insolution after depleting albumin. The analysisindicates that a simple mucus lysis methodcan evaluate the electrophoresis and digestionin solution techniques. Studying humanintestinal mucus complexes is importantbecause they perform two essential survivalfunctions for humans as the first biochemicaland physical defences for the gastrointestinaltract and a habitat for intestinal microbiota,which are primarily hosted in the colon andexceeds the human genetic information andcell number 100- and 10-fold (1.

  2. Interaction of Campylobacter spp. and human probiotics in chicken intestinal mucus.

    Science.gov (United States)

    Ganan, M; Martinez-Rodriguez, A J; Carrascosa, A V; Vesterlund, S; Salminen, S; Satokari, R

    2013-03-01

    Campylobacter is the most common cause of bacterial food-borne diarrhoeal disease throughout the world. The principal risk of human contamination is handling and consumption of contaminated poultry meat. To colonize poultry, Campylobacter adheres to and persists in the mucus layer that covers the intestinal epithelium. Inhibiting adhesion to the mucus could prevent colonization of the intestine. The aim of this study was to investigate in vitro the protective effect of defined commercial human probiotic strains on the adhesion of Campylobacter spp. to chicken intestinal mucus, in a search for alternatives to antibiotics to control this food-borne pathogen. The probiotic strains Lactobacillus rhamnosus GG and Propionibacterium freudenreichii ssp. shermanii JS and a starter culture strain Lactococcus lactis ssp. lactis adhered well to chicken intestinal mucus and were able to reduce the binding of Campylobacter spp. when the mucus was colonized with the probiotic strain before contacting the pathogen. Human-intended probiotics could be useful as prophylactics in poultry feeding for controlling Campylobacter spp. colonization. © 2012 Blackwell Verlag GmbH.

  3. Transport of particles in intestinal mucus under simulated infant and adult physiological conditions: impact of mucus structure and extracellular DNA.

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    Macierzanka, Adam; Mackie, Alan R; Bajka, Balazs H; Rigby, Neil M; Nau, Françoise; Dupont, Didier

    2014-01-01

    The final boundary between digested food and the cells that take up nutrients in the small intestine is a protective layer of mucus. In this work, the microstructural organization and permeability of the intestinal mucus have been determined under conditions simulating those of infant and adult human small intestines. As a model, we used the mucus from the proximal (jejunal) small intestines of piglets and adult pigs. Confocal microscopy of both unfixed and fixed mucosal tissue showed mucus lining the entire jejunal epithelium. The mucus contained DNA from shed epithelial cells at different stages of degradation, with higher amounts of DNA found in the adult pig. The pig mucus comprised a coherent network of mucin and DNA with higher viscosity than the more heterogeneous piglet mucus, which resulted in increased permeability of the latter to 500-nm and 1-µm latex beads. Multiple-particle tracking experiments revealed that diffusion of the probe particles was considerably enhanced after treating mucus with DNase. The fraction of diffusive 500-nm probe particles increased in the pig mucus from 0.6% to 64% and in the piglet mucus from ca. 30% to 77% after the treatment. This suggests that extracellular DNA can significantly contribute to the microrheology and barrier properties of the intestinal mucus layer. To our knowledge, this is the first time that the structure and permeability of the small intestinal mucus have been compared between different age groups and the contribution of extracellular DNA highlighted. The results help to define rules governing colloidal transport in the developing small intestine. These are required for engineering orally administered pharmaceutical preparations with improved delivery, as well as for fabricating novel foods with enhanced nutritional quality or for controlled calorie uptake.

  4. Transport of particles in intestinal mucus under simulated infant and adult physiological conditions: impact of mucus structure and extracellular DNA.

    Directory of Open Access Journals (Sweden)

    Adam Macierzanka

    Full Text Available The final boundary between digested food and the cells that take up nutrients in the small intestine is a protective layer of mucus. In this work, the microstructural organization and permeability of the intestinal mucus have been determined under conditions simulating those of infant and adult human small intestines. As a model, we used the mucus from the proximal (jejunal small intestines of piglets and adult pigs. Confocal microscopy of both unfixed and fixed mucosal tissue showed mucus lining the entire jejunal epithelium. The mucus contained DNA from shed epithelial cells at different stages of degradation, with higher amounts of DNA found in the adult pig. The pig mucus comprised a coherent network of mucin and DNA with higher viscosity than the more heterogeneous piglet mucus, which resulted in increased permeability of the latter to 500-nm and 1-µm latex beads. Multiple-particle tracking experiments revealed that diffusion of the probe particles was considerably enhanced after treating mucus with DNase. The fraction of diffusive 500-nm probe particles increased in the pig mucus from 0.6% to 64% and in the piglet mucus from ca. 30% to 77% after the treatment. This suggests that extracellular DNA can significantly contribute to the microrheology and barrier properties of the intestinal mucus layer. To our knowledge, this is the first time that the structure and permeability of the small intestinal mucus have been compared between different age groups and the contribution of extracellular DNA highlighted. The results help to define rules governing colloidal transport in the developing small intestine. These are required for engineering orally administered pharmaceutical preparations with improved delivery, as well as for fabricating novel foods with enhanced nutritional quality or for controlled calorie uptake.

  5. A mucus adhesion promoting protein, MapA, mediates the adhesion of Lactobacillus reuteri to Caco-2 human intestinal epithelial cells.

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    Miyoshi, Yukihiro; Okada, Sanae; Uchimura, Tai; Satoh, Eiichi

    2006-07-01

    Lactobacillus reuteri is one of the dominant lactobacilli found in the gastrointestinal tract of various animals. A surface protein of L. reuteri 104R, mucus adhesion promoting protein (MapA), is considered to be an adhesion factor of this strain. We investigated the relation between MapA and adhesion of L. reuteri to human intestinal (Caco-2) cells. Quantitative analysis of the adhesion of L. reuteri strains to Caco-2 cells showed that various L. reuteri strains bind not only to mucus but also to intestinal epithelial cells. In addition, purified MapA bound to Caco-2 cells, and this binding inhibited the adhesion of L. reuteri in a concentration-dependent manner. Based on these observations, the adhesion of L. reuteri appears due to the binding of MapA to receptor-like molecules on Caco-2 cells. Further, far-western analysis indicated the existence of multiple receptor-like molecules in Caco-2 cells.

  6. Intestinal mucus accumulation in a child with acutemyeloblastic leukemia

    Directory of Open Access Journals (Sweden)

    Namık Özbek

    2009-12-01

    Full Text Available Intestinal mucus accumulation is a very rare situation observed in some solid tumors, intestinal inflammation, mucosal hyperplasia, elevated intestinal pressure, and various other diseases. However, it has never been described in acute myeloblastic leukemia. The pathogenesis of intestinal mucus accumulation is still not clear. Here, we report a 14-year-old girl with acute myeloblastic leukemia and febrile neutropenia in addition to typhlitis. She was also immobilized due to joint contractures of the lower extremities and had intestinal mucus accumulation, which was, at first, misdiagnosed as intestinal parasitosis. We speculate that typhlitis, immobilization and decreased intestinal motility due to usage of antiemetic drugs might have been the potential etiologic factors in this case. However, its impact on prognosis of the primary disease is unknown.

  7. Sodium alginate decreases the permeability of intestinal mucus

    OpenAIRE

    Mackie, Alan R.; Macierzanka, Adam; Aarak, Kristi; Rigby, Neil M.; Parker, Roger; Channell, Guy A.; Stephen E. Harding; Balazs H Bajka

    2016-01-01

    In the small intestine the nature of the environment leads to a highly heterogeneous mucus layer primarily composed of the MUC2 mucin. We set out to investigate whether the soluble dietary fibre sodium alginate could alter the permeability of the mucus layer. The alginate was shown to freely diffuse into the mucus and to have minimal effect on the bulk rheology when added at concentrations below 0.1%. Despite this lack of interaction between the mucin and alginate, the addition of alginate ha...

  8. Sodium alginate decreases the permeability of intestinal mucus.

    Science.gov (United States)

    Mackie, Alan R; Macierzanka, Adam; Aarak, Kristi; Rigby, Neil M; Parker, Roger; Channell, Guy A; Harding, Stephen E; Bajka, Balazs H

    2016-01-01

    In the small intestine the nature of the environment leads to a highly heterogeneous mucus layer primarily composed of the MUC2 mucin. We set out to investigate whether the soluble dietary fibre sodium alginate could alter the permeability of the mucus layer. The alginate was shown to freely diffuse into the mucus and to have minimal effect on the bulk rheology when added at concentrations below 0.1%. Despite this lack of interaction between the mucin and alginate, the addition of alginate had a marked effect on the diffusion of 500 nm probe particles, which decreased as a function of increasing alginate concentration. Finally, we passed a protein stabilised emulsion through a simulation of oral, gastric and small intestinal digestion. We subsequently showed that the addition of 0.1% alginate to porcine intestinal mucus decreased the diffusion of fluorescently labelled lipid present in the emulsion digesta. This reduction may be sufficient to reduce problems associated with high rates of lipid absorption such as hyperlipidaemia.

  9. Property profiling of biosimilar mucus in a novel mucus-containing in vitro model for assessment of intestinal drug absorption

    DEFF Research Database (Denmark)

    Bøgh, Marie; Baldursdóttir, Stefania G; Müllertz, Anette;

    2014-01-01

    comparable to freshly isolated porcine intestinal mucus (PIM). Further, this multicomponent biosimilar mucus mixture was optimized with regards to the lipid content in order to obtain cellular biocompatibility with well-differentiated Caco-2 cell monolayers. In contrast, PIM was found to severely disrupt...... of the biorelevance of the Caco-2 cell culture model by application of mucus, resulting in an in vitro model of oral mucosa suitable for future assessment of innovative drug delivery approaches....

  10. Analyses of human colonic mucus obtained by an in vivo sampling technique

    NARCIS (Netherlands)

    Hamer, H.M.; Jonkers, D.M.A.E.; Loof, A.; Houtvin, S.A.L.W. van; Troost, F.J.; Venema, K.; Kodde, A.; Koek, G.H.; Schipper, R.G.; Heerde, W.L. van; Brummer, R.J.

    2009-01-01

    Background: The mucus layer is an important dynamic component of the epithelial barrier. It contains mucin glycoproteins and other compounds secreted by the intestinal epithelium, such as secretory IgA. However, a standardized in vivo sampling technique of mucus in humans is not yet available. Aim:

  11. Antibacterial activity of human cervical mucus.

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    Zuckerman, H; Kahana, A; Carmel, S

    1975-01-01

    The antimicrobial property of human uterine cervical mucus was tested in three groups of women. Healthy women, using no contraception, women using an intrauterine device and women receiving hormonal treatment for contraception. Cervical mucus was taken on the 10th, 14th, 18th and 22nd day of the menstrual cycle. Cervical mucus had a strong inhibitory effect on the growth of Micrococcus lysodeicticus in all three groups. The strength of the inhibitory effect on the other microorganisms were in the following order: Staphylococcus albus, Staphylococcus aureus, Proteus mirabilis, Escherichia coli, Candida albicans, Streptococcus haemolyticus, Streptococcus faecalis. Use of an intrauterine device did not affect the antimicrobial effect of cervical mucus. The use of hormonal contraceptive canceled the antimicrobial effect on the series of microorganisms, with the exception of M. lysodeicticus. The maximum inhibitory effect occurred on the 14th day and declined toward the end of the menstrual cycle.

  12. Different macro- and micro-rheological properties of native porcine respiratory and intestinal mucus.

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    Bokkasam, Harish; Ernst, Matthias; Guenther, Marco; Wagner, Christian; Schaefer, Ulrich F; Lehr, Claus-Michael

    2016-08-20

    Aim of this study was to investigate the similarities and differences at macro- and microscale in the viscoelastic properties of mucus that covers the epithelia of the intestinal and respiratory tract. Natural mucus was collected from pulmonary and intestinal regions of healthy pigs. Macro-rheological investigations were carried out through conventional plate-plate rheometry. Microrheology was investigated using optical tweezers. Our data revealed significant differences both in macro- and micro-rheological properties between respiratory and intestinal mucus.

  13. Property profiling of biosimilar mucus in a novel mucus-containing in vitro model for assessment of intestinal drug absorption.

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    Boegh, Marie; Baldursdóttir, Stefania G; Müllertz, Anette; Nielsen, Hanne M

    2014-07-01

    Oral delivery of drugs, including peptide and protein therapeutics, can be impeded by the presence of the mucus surface-lining the intestinal epithelium. The aim of the present project was to design and characterize biosimilar mucus compatible with Caco-2 cell monolayers cultured in vitro to establish a more representative in vitro model for the intestinal mucosa. The rheological profile of a biosimilar mucus mixture composed of purified gastric mucin, lipids and protein in buffer was optimized by supplementing with an anionic polymer to display viscoelastic properties and a microstructure comparable to freshly isolated porcine intestinal mucus (PIM). Further, this multicomponent biosimilar mucus mixture was optimized with regard to the lipid content in order to obtain cellular compatibility with well-differentiated Caco-2 cell monolayers. In contrast, PIM was found to severely disrupt the Caco-2 cell monolayer. When combined with the Caco-2 cell monolayers, the final biosimilar mucus was found to significantly affect the permeability profiles for hydrophobic and hydrophilic small and large model drug compounds in different ways. In conclusion, the present study describes an improvement of the biorelevance of the Caco-2 cell culture model by application of mucus, resulting in an in vitro model of oral mucosa suitable for future assessment of innovative drug delivery approaches. Copyright © 2014. Published by Elsevier B.V.

  14. Studies of mucus in mouse stomach, small intestine, and colon. I. Gastrointestinal mucus layers have different properties depending on location as well as over the Peyer's patches.

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    Ermund, Anna; Schütte, André; Johansson, Malin E V; Gustafsson, Jenny K; Hansson, Gunnar C

    2013-09-01

    Colon has been shown to have a two-layered mucus system where the inner layer is devoid of bacteria. However, a complete overview of the mouse gastrointestinal mucus system is lacking. We now characterize mucus release, thickness, growth over time, adhesive properties, and penetrability to fluorescent beads from stomach to distal colon. Colon displayed spontaneous mucus release and all regions released mucus in response to carbachol and PGE2, except the distal colon and domes of Peyer's patches. Stomach and colon had an inner mucus layer that was adherent to the epithelium. In contrast, the small intestine and Peyer's patches had a single mucus layer that was easily aspirated. The inner mucus layer of the distal colon was not penetrable to beads the size of bacteria and the inner layer of the proximal colon was only partly penetrable. In contrast, the inner mucus layer of stomach was fully penetrable, as was the small intestinal mucus. This suggests a functional organization of the intestinal mucus system, where the small intestine has loose and penetrable mucus that may allow easy penetration of nutrients, in contrast to the stomach, where the mucus provides physical protection, and the colon, where the mucus separates bacteria from the epithelium. This knowledge of the mucus system and its organization improves our understanding of the gastrointestinal tract physiology.

  15. Intestinal Mucus Gel and Secretory Antibody are Barriers to Campylobacter jejuni Adherence to INT 407 Cells

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    1987-06-01

    An in vitro mucus assay was developed to study the role of mucus gel and secretory immunoglobulin A (sIgA) in preventing attachment of Campylobacter ... jejuni to INT 407 cells. An overlay of rabbit small intestinal mucus was found to impede the attachment of C. jejuni to a monolayer of INT 407 cells

  16. Steric and interactive barrier properties of intestinal mucus elucidated by particle diffusion and peptide permeation.

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    Boegh, Marie; García-Díaz, María; Müllertz, Anette; Nielsen, Hanne Mørck

    2015-09-01

    The mucus lining of the gastrointestinal tract epithelium is recognized as a barrier to efficient oral drug delivery. Recently, a new in vitro model for assessment of drug permeation across intestinal mucosa was established by applying a biosimilar mucus matrix to the surface of Caco-2 cell monolayers. The aim of the present study was to gain more insight into the steric and interactive barrier properties of intestinal mucus by studying the permeation of peptides and model compounds across the biosimilar mucus as well as across porcine intestinal mucus (PIM). As PIM disrupted the Caco-2 cell monolayers, a cell-free mucus barrier model was implemented in the studies. Both the biosimilar mucus and the PIM reduced the permeation of the selected peptide drugs to varying degrees illustrating the interactive properties of both mucus matrices. The reduction in peptide permeation was decreased depending on the cationicity and H-bonding capacity of the permeant clearly demonstrated by using the biosimilar mucus, whereas the larger inter sample variation of the PIM matrix obstructed similarly clear conclusions. Thus, for mechanistic studies of permeation across mucus and mucosa the biosimilar mucus offers a relevant and reproducible alternative to native mucus. Copyright © 2015 Elsevier B.V. All rights reserved.

  17. The influence of small intestinal mucus structure on particle transport ex vivo.

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    Bajka, Balázs H; Rigby, Neil M; Cross, Kathryn L; Macierzanka, Adam; Mackie, Alan R

    2015-11-01

    Mucus provides a barrier to bacteria and toxins while allowing nutrient absorption and waste transport. Unlike colonic mucus, small intestinal mucus structure is poorly understood. This study aimed to provide evidence for a continuous, structured mucus layer and assess the diffusion of different sized particles through it. Mucus structure was assessed by histology and immunohistochemistry. Ultra-structure was assessed by scanning electron microscopy. Tracking of 100 nm and 500 nm latex beads was conducted using ex vivo porcine mucus. The porcine jejunum and ileum were filled with mucus. Layered MUC2 staining was visible throughout the small intestine, covering villus tips. Scanning electron microscopy showed net-like mucin sheets covering villi (211 ± 7 nm pore diameter). Particle tracking of 100 nm latex beads, showed no inhibition of diffusion through mucus while 500 nm beads displayed limited diffusion. These results suggest a continuous mucus layer exists throughout the small intestine, which is highly stratified adjacent to the epithelium. The network observed is consistent with previous observations and correlates with stratified MUC2 staining. Mucin pore size is consistent with free diffusion of 100 nm and limited diffusion of 500 nm particles. Small Intestinal mucus structure has important implications for drug delivery systems and prevention and treatment of conditions like mucositis and inflammatory bowel disease.

  18. The effect of nanoparticle permeation on the bulk rheological properties of mucus from the small intestine.

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    Wilcox, M D; Van Rooij, L K; Chater, P I; Pereira de Sousa, I; Pearson, J P

    2015-10-01

    The effectiveness of delivering oral therapeutic peptides, proteins and nucleotides is often hindered by the protective mucus barrier that covers mucosal surfaces of the gastrointestinal (GI) tract. Encapsulation of active pharmaceutical ingredients (API) in nanocarriers is a potential strategy to protect the cargo but they still have to pass the mucus barrier. Decorating nanoparticles with proteolytic enzymes has been shown to increase the permeation through mucus. Here we investigate the effect of poly(acrylic acid) (PAA) nanoparticles decorated with bromelain (BRO), a proteolytic enzyme from pineapple stem, on the bulk rheology of mucus as well as non-decorated poly(lactic-co-glycolic acid) (PLGA) nanoparticles. Porcine intestinal mucus from the small intestine was incubated for 30min in the presence of PLGA nanoparticles or polyacrylic nanoparticles decorated with bromelain (PAA-BRO). The effect of nanoparticles on the rheological properties, weight of gel, released glycoprotein content from mucus as well as the viscosity of liquid removed was assessed. Treatment with nanoparticles decreased mucus gel strength with PAA-BRO reducing it the most. PAA-BRO nanoparticles resulted in the release of increased glycoprotein from the gel network whereas mucus remained a gel and exhibited a similar breakdown stress to control mucus. Therefore it would be possible to use bromelain to increase the permeability of nanoparticles through mucus without destroying the gel and leaving the underlying mucosa unprotected.

  19. Micro-configuration Observation of Porous Bioceramic for Sliding on Intestinal Mucus Film

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    The microstructure of the prepared porous bioceramic material, including surface porosity and apparent contact area with the artificial mucus film are computed and analyzed. The surface micro-configurations of the porous material before and after sliding on the mucus ftlm are observed in 2D and 3 D by digital microscopy. We describe how much mucus enters and stays within different pores, and how the porous material with rough/porous surface contacts with the mucus film ( elastic surface/gel). The presented results illustrate that the material with different porous structure can lead to different mucus suction, surface scraping and changes of contact area and condition during sliding, which will be active for high friction of robotic endoscope with the intestinal wall for intestinal locomotion.

  20. Goblet Cells and Mucus Types in the Digestive Intestine and Respiratory Intestine in Bronze Corydoras (Callichthyidae: Teleostei).

    Science.gov (United States)

    Leknes, I L

    2015-10-01

    The structure and histochemical properties of the intestine in bronze corydoras (Corydoras aeneus), a stomach-containing teleost, are described, with emphasis on goblet cells and mucin types. The proximal intestine displayed a normal structure for teleosts, whereas the distal intestine was wide, translucent, thin-walled, richly vascularized and constantly filled with air, suggesting an important respiratory role. Goblet cells were common throughout the entire intestine and displayed a variable, but mainly faint metachromatic colour after toluidine blue. They were moderately coloured by alcian blue at both pH 2.5 and 0.2 and displayed no colour after periodic acid followed by Schiff's solution (PAS), but a distinct purple-brown colour after high iron diamine followed by alcian blue (pH 2.5). Together, these results suggest that the mucin in the intestine goblet cells consists mainly of sulphated proteoglycans. Further, the results from the present lectin and neuraminidase tests suggest that these mucins contain much N-acetylglucoseamines and some N-acetylgalactosamines and sialic acid, but seem to lack glucose and mannose. They also contain some galactose-N-acetylgalactosamines sequences, normally hidden by sialic acid. The distinct brush border and mucus layer on the epithelial cells in the respiratory intestine may indicate some digestive roles, such as absorption of water, ions and simple carbohydrates. As sulphated proteoglycans are tough and attract much water, this mucus may play important roles in the protection against mechanical and chemical damages and in the defence against micro-organisms throughout the entire intestine, but in the respiratory intestine it may impede significantly the oxygen uptake. However, as this part of the intestine usually contains no digesta, but is completely filled with air, frequently renewed by dry air from the atmosphere, and the main function of the mucus may be to protect the respiratory epithelium against a destroying and

  1. Comparative genomic analysis of Lactobacillus rhamnosus GG reveals pili containing a human- mucus binding protein.

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    Kankainen, Matti; Paulin, Lars; Tynkkynen, Soile; von Ossowski, Ingemar; Reunanen, Justus; Partanen, Pasi; Satokari, Reetta; Vesterlund, Satu; Hendrickx, Antoni P A; Lebeer, Sarah; De Keersmaecker, Sigrid C J; Vanderleyden, Jos; Hämäläinen, Tuula; Laukkanen, Suvi; Salovuori, Noora; Ritari, Jarmo; Alatalo, Edward; Korpela, Riitta; Mattila-Sandholm, Tiina; Lassig, Anna; Hatakka, Katja; Kinnunen, Katri T; Karjalainen, Heli; Saxelin, Maija; Laakso, Kati; Surakka, Anu; Palva, Airi; Salusjärvi, Tuomas; Auvinen, Petri; de Vos, Willem M

    2009-10-06

    To unravel the biological function of the widely used probiotic bacterium Lactobacillus rhamnosus GG, we compared its 3.0-Mbp genome sequence with the similarly sized genome of L. rhamnosus LC705, an adjunct starter culture exhibiting reduced binding to mucus. Both genomes demonstrated high sequence identity and synteny. However, for both strains, genomic islands, 5 in GG and 4 in LC705, punctuated the colinearity. A significant number of strain-specific genes were predicted in these islands (80 in GG and 72 in LC705). The GG-specific islands included genes coding for bacteriophage components, sugar metabolism and transport, and exopolysaccharide biosynthesis. One island only found in L. rhamnosus GG contained genes for 3 secreted LPXTG-like pilins (spaCBA) and a pilin-dedicated sortase. Using anti-SpaC antibodies, the physical presence of cell wall-bound pili was confirmed by immunoblotting. Immunogold electron microscopy showed that the SpaC pilin is located at the pilus tip but also sporadically throughout the structure. Moreover, the adherence of strain GG to human intestinal mucus was blocked by SpaC antiserum and abolished in a mutant carrying an inactivated spaC gene. Similarly, binding to mucus was demonstrated for the purified SpaC protein. We conclude that the presence of SpaC is essential for the mucus interaction of L. rhamnosus GG and likely explains its ability to persist in the human intestinal tract longer than LC705 during an intervention trial. The presence of mucus-binding pili on the surface of a nonpathogenic Gram-positive bacterial strain reveals a previously undescribed mechanism for the interaction of selected probiotic lactobacilli with host tissues.

  2. Adhesive mucous gel layer and mucus release as intestinal barrier in rats.

    Science.gov (United States)

    Iiboshi, Y; Nezu, R; Cui, L; Chen, K; Khan, J; Yoshida, H; Sando, K; Kamata, S; Takagi, Y; Okada, A

    1996-01-01

    Although it has been reported that total parenteral nutrition induces an increased intestinal permeability and a decreased mucous gel layer covering the intestinal epithelium, the role of mucous gel on intestinal permeability has not been well understood. We examined the in vivo effects of N-acetyl cysteine (NAC) as mucolytic agent and colchicine as suppressant of the mucus production on the intestinal transmission of fluorescein isothiocyanate dextran 70,000 (FITC-dextran). Rats were divided into four groups. In each group, FITC-dextran (750 mg/kg) with or without NAC (3000 mg/kg) was injected into the small intestinal lumen 3 hours after intraperitoneal injection of saline or colchicine (Col, 10 mg/kg). Thirty minutes after injection of FITC-dextran, blood samples were taken from portal vein to analyze plasma fluorescein concentration by fluorescence spectrometry. Samples of small intestine were sectioned in a cryostat for fluorescence microscopy, and the identical sections were stained by periodic acid-Schiff reaction. Plasma FITC-dextran level in NAC group was higher than that in control group (p NAC group was higher than that in Col group (p NAC group was higher than that in NAC group (p NAC and Col + NAC groups. FITC-dextran and mucous gel showed complementary distribution in all rats. The villous interstitial edema was recognized in NAC group and the villi were disrupted in Col + NAC group. These results suggest that intestinal permeability is possibly affected not only by the mucous gel covering the intestinal epithelium but also by mucus release from goblet cells of the small intestine.

  3. The protein disulfide isomerase AGR2 is essential for production of intestinal mucus.

    Science.gov (United States)

    Park, Sung-Woo; Zhen, Guohua; Verhaeghe, Catherine; Nakagami, Yasuhiro; Nguyenvu, Louis T; Barczak, Andrea J; Killeen, Nigel; Erle, David J

    2009-04-28

    Protein disulfide isomerases (PDIs) aid protein folding and assembly by catalyzing formation and shuffling of cysteine disulfide bonds in the endoplasmic reticulum (ER). Many members of the PDI family are expressed in mammals, but the roles of specific PDIs in vivo are poorly understood. A recent homology-based search for additional PDI family members identified anterior gradient homolog 2 (AGR2), a protein originally presumed to be secreted by intestinal epithelial cells. Here, we show that AGR2 is present within the ER of intestinal secretory epithelial cells and is essential for in vivo production of the intestinal mucin MUC2, a large, cysteine-rich glycoprotein that forms the protective mucus gel lining the intestine. A cysteine residue within the AGR2 thioredoxin-like domain forms mixed disulfide bonds with MUC2, indicating a direct role for AGR2 in mucin processing. Mice lacking AGR2 were viable but were highly susceptible to colitis, indicating a critical role for AGR2 in protection from disease. We conclude that AGR2 is a unique member of the PDI family, with a specialized and nonredundant role in intestinal mucus production.

  4. Altered mucus glycosylation in core 1 O-glycan-deficient mice affects microbiota composition and intestinal architecture.

    Science.gov (United States)

    Sommer, Felix; Adam, Nina; Johansson, Malin E V; Xia, Lijun; Hansson, Gunnar C; Bäckhed, Fredrik

    2014-01-01

    A functional mucus layer is a key requirement for gastrointestinal health as it serves as a barrier against bacterial invasion and subsequent inflammation. Recent findings suggest that mucus composition may pose an important selection pressure on the gut microbiota and that altered mucus thickness or properties such as glycosylation lead to intestinal inflammation dependent on bacteria. Here we used TM-IEC C1galt (-/-) mice, which carry an inducible deficiency of core 1-derived O-glycans in intestinal epithelial cells, to investigate the effects of mucus glycosylation on susceptibility to intestinal inflammation, gut microbial ecology and host physiology. We found that TM-IEC C1galt (-/-) mice did not develop spontaneous colitis, but they were more susceptible to dextran sodium sulphate-induced colitis. Furthermore, loss of core 1-derived O-glycans induced inverse shifts in the abundance of the phyla Bacteroidetes and Firmicutes. We also found that mucus glycosylation impacts intestinal architecture as TM-IEC C1galt(-/-) mice had an elongated gastrointestinal tract with deeper ileal crypts, a small increase in the number of proliferative epithelial cells and thicker circular muscle layers in both the ileum and colon. Alterations in the length of the gastrointestinal tract were partly dependent on the microbiota. Thus, the mucus layer plays a role in the regulation of gut microbiota composition, balancing intestinal inflammation, and affects gut architecture.

  5. Competition for attachment of aquaculture candidate probiotic and pathogenic bacteria on fish intestinal mucus.

    Science.gov (United States)

    Vine, N G; Leukes, W D; Kaiser, H; Daya, S; Baxter, J; Hecht, T

    2004-06-01

    Probiotics for aquaculture are generally only selected by their ability to produce antimicrobial metabolites; however, attachment to intestinal mucus is important in order to remain within the gut of its host. Five candidate probiotics (AP1-AP5), isolated from the clownfish, Amphiprion percula (Lacepéde), were examined for their ability to attach to fish intestinal mucus and compete with two pathogens, Aeromonas hydrophila and Vibrio alginolyticus. Two different radioactive isotopes were used to quantify competition between pathogens and probionts. Attachment of the pathogens was enhanced by the presence of the candidate probiotics. However, the addition of the candidate probiotics after the pathogens resulted in reduced pathogen attachment. Only AP5 caused lower attachment success of V. alginolyticus when added before the pathogen. When AP5 was added first, the average attachment change was 41% compared with 72% when added after V. alginolyticus, suggesting that the probiotic is displaced but that enhanced attachment of the pathogen does not occur. Conversely, when V. alginolyticus was added first, followed by AP5, attachment change was 37% while AP5 had 92% attachment change when added second. This implies that the pathogen was displaced by the candidate probiotic and therefore it appeared that, based on the ability of probiont AP5 to attach to mucus, the growth of the pathogen in the digestive tract might be suppressed by the candidate probiont's presence.

  6. Imaging and tracking HIV viruses in human cervical mucus

    Science.gov (United States)

    Boukari, Fatima; Makrogiannis, Sokratis; Nossal, Ralph; Boukari, Hacène

    2016-09-01

    We describe a systematic approach to image, track, and quantify the movements of HIV viruses embedded in human cervical mucus. The underlying motivation for this study is that, in HIV-infected adults, women account for more than half of all new cases and most of these women acquire the infection through heterosexual contact. The endocervix is believed to be a susceptible site for HIV entry. Cervical mucus, which coats the endocervix, should play a protective role against the viruses. Thus, we developed a methodology to apply time-resolved confocal microscopy to examine the motion of HIV viruses that were added to samples of untreated cervical mucus. From the images, we identified the viruses, tracked them over time, and calculated changes of the statistical mean-squared displacement (MSD) of each virus. Approximately half of tracked viruses appear constrained while the others show mobility with MSDs that are proportional to τα+ν2τ2, over time range τ, depicting a combination of anomalous diffusion (0<α<0.4) and flow-like behavior. The MSD data also reveal plateaus attributable to possible stalling of the viruses. Although a more extensive study is warranted, these results support the assumption of mucus being a barrier against the motion of these viruses.

  7. Comparison of the Caco-2, HT-29 and the mucus-secreting HT29-MTX intestinal cell models to investigate Salmonella adhesion and invasion.

    Science.gov (United States)

    Gagnon, Mélanie; Zihler Berner, Annina; Chervet, Noémie; Chassard, Christophe; Lacroix, Christophe

    2013-09-01

    Human intestinal cell models are widely used to study host-enteric pathogen interactions, with different cell lines exhibiting specific characteristics and functions in the gut epithelium. In particular, the presence of mucus may play an important role in adhesion and invasion of pathogens. The aim of this study was to evaluate the suitability of the mucus-secreting HT29-MTX intestinal epithelial cell model to test adhesion and invasion of Salmonella strains and compare with data obtained with the more commonly used Caco-2 and HT-29 models. Adhesion of Salmonella to HT29-MTX cell model was significantly higher, likely due to high adhesiveness to mucins present in the native human mucus layer covering the whole cell surface, compared to the non- and low-mucus producing Caco-2 and HT-29 cell models, respectively. In addition, invasion percentages of some clinical Salmonella strains to HT29-MTX cultures were remarkably higher than to Caco-2 and HT-29 cells suggesting that these Salmonellae have subverted the mucus to enhance pathogenicity. The transepithelial electrical resistances of the infected HT29-MTX cell model decreased broadly and were highly correlated with invasion ability of the strain. Staining of S. Typhimurium-infected cell epithelium confirmed the higher invasion by Salmonella and subsequent disruption of tight junctions of HT29-MTX cell model compared with the Caco-2 and HT-29 cell models. Data from this study suggest that the HT29-MTX cell model, with more physiologically relevant characteristics with the mucus layer formation, could be better suited for studying cells-pathogens interactions.

  8. Changes in the Mucus Barrier during Cisplatin-Induced Intestinal Mucositis in Rats

    Directory of Open Access Journals (Sweden)

    Hajime Yamamoto

    2013-01-01

    Full Text Available Aim. Gastrointestinal mucositis is a frequent complication of antineoplastic chemotherapy, but the effects of chemotherapy on mucosal defense mechanisms remain poorly understood. We studied the effects of cisplatin on mucin, one of the principal defense factors of the gastrointestinal mucosa, and evaluated the efficacy of two different types of H2-receptor antagonists against cisplatin-induced mucositis. Methods. Cisplatin (6 mg/kg was administered intravenously to rats (day 0. The rats were sacrificed 1, 3, 7, and 11 days after treatment, and their stomach, jejunum, ileum, and colon were removed. Immunoreactivity of the mucosa was compared with the use of anti-mucin monoclonal antibody. To evaluate the efficacy of H2-receptor antagonists, either famotidine (3 mg/kg or lafutidine (30 mg/kg was given orally once daily on days 0, 1, and 2. Histological and biochemical findings were compared among the groups to assess effects on cisplatin-induced injury. Results. Cisplatin significantly altered the immunoreactivity and content of mucin in the small intestinal mucosa, especially in the ileum. Lafutidine protected against cisplatin-induced mucosal injury and attenuated decreased mucin accumulation. Conclusion. Cisplatin appears to alter the mucus barrier function in the intestinal mucosa. Lafutidine might effectively prevent chemotherapy-induced mucositis by activating intestinal mucus cells.

  9. Stress disrupts intestinal mucus barrier in rats via mucin O-glycosylation shift: prevention by a probiotic treatment.

    Science.gov (United States)

    Da Silva, Stéphanie; Robbe-Masselot, Catherine; Ait-Belgnaoui, Afifa; Mancuso, Alessandro; Mercade-Loubière, Myriam; Salvador-Cartier, Christel; Gillet, Marion; Ferrier, Laurent; Loubière, Pascal; Dague, Etienne; Theodorou, Vassilia; Mercier-Bonin, Muriel

    2014-08-15

    Despite well-known intestinal epithelial barrier impairment and visceral hypersensitivity in irritable bowel syndrome (IBS) patients and IBS-like models, structural and physical changes in the mucus layer remain poorly understood. Using a water avoidance stress (WAS) model, we aimed at evaluating whether 1) WAS modified gut permeability, visceral sensitivity, mucin expression, biochemical structure of O-glycans, and related mucus physical properties, and 2) whether Lactobacillus farciminis treatment prevented these alterations. Wistar rats received orally L. farciminis or vehicle for 14 days; at day 10, they were submitted to either sham or 4-day WAS. Intestinal paracellular permeability and visceral sensitivity were measured in vivo. The number of goblet cells and Muc2 expression were evaluated by histology and immunohistochemistry, respectively. Mucosal adhesion of L. farciminis was determined ex situ. The mucin O-glycosylation profile was obtained by mass spectrometry. Surface imaging of intestinal mucus was performed at nanoscale by atomic force microscopy. WAS induced gut hyperpermeability and visceral hypersensitivity but did not modify either the number of intestinal goblet cells or Muc2 expression. In contrast, O-glycosylation of mucins was strongly affected, with the appearance of elongated polylactosaminic chain containing O-glycan structures, associated with flattening and loss of the mucus layer cohesive properties. L. farciminis bound to intestinal Muc2 and prevented WAS-induced functional alterations and changes in mucin O-glycosylation and mucus physical properties. WAS-induced functional changes were associated with mucus alterations resulting from a shift in O-glycosylation rather than from changes in mucin expression. L. farciminis treatment prevented these alterations, conferring epithelial and mucus barrier strengthening.

  10. Influence of the gut microbiota on transcriptional regulation of genes involved in early life development of the intestinal mucus layer

    DEFF Research Database (Denmark)

    Bergström, Anders; Kristensen, Matilde Bylov; Metzdorff, Stine Broeng

    2010-01-01

    The interplay between the gut microbiota and the intestinal mucus layer is important both in the maintenance of the epithelial barrier as part of the innate immune defense, and in the conservation of gut homeostasis. Little is known about how the microbiota regulates mucin proteins, which protect...... the mucosal surfaces of all epithelial linings by physical hindrance or specific binding of pathogenic agents including virus and bacteria. It has been shown that the presence and composition of the microbiota is directly involved in the regulation of gene transcription in the intestinal epithelium....... The intestinal mucus layer of germ free mice has been shown to display a distinctly different composition and structure compared to mucus from conventionally bred animals in vitro and in vivo. This points towards an important role of the microbiota in the regulation of mucin production. To which extent...

  11. Influence of the gut microbiota on transcriptional regulation of genes involved in early life development of the intestinal mucus layer

    DEFF Research Database (Denmark)

    Bergström, Anders; Kristensen, Matilde Bylov; Metzdorff, Stine Broeng

    The interplay between the gut microbiota and the intestinal mucus layer is important both in the maintenance of the epithelial barrier as part of the innate immune defense, and in the conservation of gut homeostasis. Little is known about how the microbiota regulates mucin proteins, which protect...... the mucosal surfaces of all epithelial linings by physical hindrance or specific binding of pathogenic agents including virus and bacteria. It has been shown that the presence and composition of the microbiota is directly involved in the regulation of gene transcription in the intestinal epithelium....... The intestinal mucus layer of germ free mice has been shown to display a distinctly different composition and structure compared to mucus from conventionally bred animals in vitro and in vivo. This points towards an important role of the microbiota in the regulation of mucin production. To which extent...

  12. Bacillus cereus Adhesion to Simulated Intestinal Mucus Is Determined by Its Growth on Mucin, Rather Than Intestinal Environmental Parameters.

    Science.gov (United States)

    Tsilia, Varvara; Uyttendaele, Mieke; Kerckhof, Frederiek-Maarten; Rajkovic, Andreja; Heyndrickx, Marc; Van de Wiele, Tom

    2015-11-01

    Adhesion of pathogenic bacteria to intestinal mucus, the protective layer of the gastrointestinal epithelium, is often considered a virulence factor. The ability of food-poisoning Bacillus cereus strains to attach to mucus and the factors affecting this interaction have not yet been investigated. Therefore, the role of adhesion in pathogenesis of B. cereus still remains unknown. In the present study, an in vitro assay based on mucin agar was used to simulate adhesion of B. cereus to mucus. Bacterial-associated factors (e.g., strain specificity and microbial competition) known to influence adhesion to different surfaces and a variety of environmental conditions (e.g., pH and oxygen) encountered in the gastrointestinal tract were investigated. The effect of these parameters on B. cereus NVH 0500/00 mucin adhesion was generally limited even in the presence of microbial competition. This suggests that B. cereus NVH 0500/00 is a versatile pathogen. Inoculation of 4 to 5 log colony-forming units (CFU) per milliliter. B. cereus NVH 0500/00 resulted in 5-6 log CFU/mL mucin-associated bacteria after a short incubation period. This indicates that this pathogenic strain could grow in the presence of mucin agar. This growth may potentially mask the effect of the studied conditions. Yet, extensive attachment of B. cereus to mucin is not necessarily a prerequisite for virulence, because other pathogenic strains do not adhere with the same efficiency to mucin. Nevertheless, adhesion may contribute to the disease by providing close contact to nutrient sources, such as mucin, which would not only result in bacterial proliferation, but also in disruption of the protective host mucus surface.

  13. Acidic Conditions in the NHE2-/- Mouse Intestine Result in an Altered Mucosa-Associated Bacterial Population with Changes in Mucus Oligosaccharides

    Directory of Open Access Journals (Sweden)

    Melinda A. Engevik

    2013-12-01

    Full Text Available Background: The mechanisms bacteria use to proliferate and alter the normal bacterial composition remain unknown. The ability to link changes in the intestinal micro-environment, such as ion composition and pH, to bacterial proliferation is clinically advantageous for diseases that involve an altered gut microbiota, such as Inflammatory Bowel Disease, obesity and diabetes. In human and mouse intestine, the apical Na+/H+ exchangers NHE2 and NHE3 affect luminal Na+, water, and pH. Loss of NHE2 results in acidic luminal pH. Since acid resistance systems in gram-positive bacteria are well documented, we hypothesize that gram-positive bacteria would increase in representation in the acidic NHE2-/- intestine. Methods: Intestinal ion composition was measured by fame photometry and chloridometry and pH measured electrochemically. DNA extracted from intestinal flushes or from mucosal scrapings was analyzed by qRT-PCR to examine luminal and mucosa-associated bacterial populations. Epithelial mucus oligosaccharide patterns were examined by histology with FIT-C labeled lectins. Results: Although total luminal and mucosa-associated bacteria were unchanged in NHE2-/- intestine, gram-positive bacterial phyla were increased in the mucosa-associated bacterial population in a region-specific manner. The genera Clostridium and Lactobacillus were increased in the cecum and colon which corresponded to changes in NHE2-/- mucus oligosaccharide composition of mannose, N-acetyglucosamine, N-acetygalactosamine and galactose. Conclusions: Together these data indicate that changes in ion transport induce region-specific bacterial changes, which alter host mucus oligosaccharide patterns. These host-bacterial interactions provide a possible mechanism of niche-development and shed insight on how certain groups proliferate in changing environments and maintain their proliferation by altering the host.

  14. Effect of pheromone induction on transfer of the Enterococcus faecalis plasmid pCF10 in intestinal mucus ex vivo

    DEFF Research Database (Denmark)

    Licht, Tine Rask; Hammerum, Anette Marie; Jensen, Lars Bogø;

    2001-01-01

    The effect of synthetic sex pheromone on pheromone-inducible conjugation between the isogenic Enterococcus faecalis strains OG1RF and OG1SS was investigated in (i) Todd-Hewitt broth medium and (ii) intestinal mucus isolated from germ-free rats. In broth, the presence of synthetic pheromone cCF10...... in the experiment. We suggest that due to differences in diffusion rates and medium-binding of the pheromones, the effect of the synthetic cCF10 was immediately dominated by the effect of pheromones produced by the recipient E. faecalis strain in broth, while this happened later in mucus....

  15. Tracing molecular and structural changes upon mucolysis with N-acetyl cysteine in human airway mucus.

    Science.gov (United States)

    Vukosavljevic, Branko; Murgia, Xabier; Schwarzkopf, Konrad; Schaefer, Ulrich F; Lehr, Claus-Michael; Windbergs, Maike

    2017-07-11

    The conducting airways of the human lungs are lined by mucus, which lubricates the lung epithelium and provides a first-line protection against airborne threats. As a novel approach for visualization of the human mucus microstructure, we applied confocal Raman microscopy as a label-free and chemically selective technique. We were successfully able to chemically resolve the pulmonary surfactant from the mucus matrix and show its spatial distribution, as well as to visualize the structural changes within the freeze-dried mucus mesh upon chemical mucolysis. Subsequently, we performed rheological measurements before and after mucolysis and correlated morphology and chemical structure of the mucus with its rheological characteristics. These results do not only enrich the knowledge about the mucus microstructure, but can also, significantly contribute to rational development of future lung therapeutics. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. Immunohistochemical detection of human intestinal spirochetosis.

    Science.gov (United States)

    Ogata, Sho; Shimizu, Ken; Oda, Tomohiro; Tominaga, Susumu; Nakanishi, Kuniaki

    2016-12-01

    Human intestinal spirochetosis (HIS) is a colorectal infection by Brachyspira species of spiral bacteria. Immunohistochemical cross-reaction to an antibody for Treponema pallidum aids its histologic diagnosis. This study's aim was to analyze the immunohistochemical characteristics of HIS. In this analysis, on 223 specimens from 83 HIS cases, we focused on so-called fringe formation (a histologic hallmark of HIS), spiral organisms within mucus or within crypts, and strong immunopositive materials in the mucosa, together with their location and the types of lesions. Fringe formation was found in 81.6% of all specimens and spiral organisms within mucus or within crypts in 97.3% and 57.0%, respectively. Strong immunopositive materials were observed in the surface epithelial layer in 87.9%, in the subepithelial layer in 94.6%, and in deeper mucosa in 2.2% of all specimens. The positive rates in conventional adenomas (24.0%, n = 146) and hyperplastic nodules (100%, n = 17) were each different from that found in inflammation (70.8%, n = 24), and spiral organisms were seen more frequently in the right-side large intestine than in the left (within mucus, 100%, n = 104 versus 95.0%, n = 119; within crypts, 65.4%, n = 104 versus 49.6%, n = 119). Thus, immunohistochemistry was effective not only in supporting the diagnosis of HIS but also in highlighting spiral organisms within mucus or crypts that were invisible in routine histology. Possibly, these spiral organisms may spread throughout the entire large intestine, although there is a potential problem with antibody specificity.

  17. Effects of laxative and N-acetylcysteine on mucus accumulation, bacterial load, transit, and inflammation in the cystic fibrosis mouse small intestine.

    Science.gov (United States)

    De Lisle, Robert C; Roach, Eileen; Jansson, Kyle

    2007-09-01

    The accumulation of mucus in affected organs is characteristic of cystic fibrosis (CF). The CF mouse small intestine has dramatic mucus accumulation and exhibits slower interdigestive intestinal transit. These factors are proposed to play cooperative roles that foster small intestinal bacterial overgrowth (SIBO) and contribute to the innate immune response of the CF intestine. It was hypothesized that decreasing the mucus accumulation would reduce SIBO and might improve other aspects of the CF intestinal phenotype. To test this, solid chow-fed CF mice were treated with an osmotic laxative to improve gut hydration or liquid-fed mice were treated orally with N-acetylcysteine (NAC) to break mucin disulfide bonds. Treatment with laxative or NAC reduced mucus accumulation by 43% and 50%, respectively, as measured histologically as dilation of the intestinal crypts. Laxative and NAC also reduced bacterial overgrowth in the CF intestine by 92% and 63%, respectively. Treatment with laxative normalized small intestinal transit in CF mice, whereas NAC did not. The expression of innate immune response-related genes was significantly reduced in laxative-treated CF mice, whereas there was no significant effect in NAC-treated CF mice. In summary, laxative and NAC treatments of CF mice reduced mucus accumulation to a similar extent, but laxative was more effective than NAC at reducing bacterial load. Eradication of bacterial overgrowth by laxative treatment was associated with normalized intestinal transit and a reduction in the innate immune response. These results suggest that both mucus accumulation and slowed interdigestive small intestinal transit contribute to SIBO in the CF intestine.

  18. Influence of the gut microbiota on transcriptional regulation of genes involved in early life development of the intestinal mucus layer

    DEFF Research Database (Denmark)

    Bergström, Anders; Kristensen, Matilde Bylov; Metzdorff, Stine Broeng

    2010-01-01

    the mucosal surfaces of all epithelial linings by physical hindrance or specific binding of pathogenic agents including virus and bacteria. It has been shown that the presence and composition of the microbiota is directly involved in the regulation of gene transcription in the intestinal epithelium...... expression of all mucin genes are dependent on the presence of microorganisms and whether specific bacteria are capable of regulating mucus production in early life remains, however, to be established. The very first period after birth is believed to be vulnerable for establishment of the gut microbiota...... animal groups and the two different days tested, which will be presented at the meeting. This is the first study to examine effects of different colonizing bacteria on mucus related gene expression levels in new born mice. These results may thus improve our understanding of the complex interplay between...

  19. Influence of the gut microbiota on transcriptional regulation of genes involved in early life development of the intestinal mucus layer

    DEFF Research Database (Denmark)

    Bergström, Anders; Kristensen, Matilde Bylov; Metzdorff, Stine Broeng

    the mucosal surfaces of all epithelial linings by physical hindrance or specific binding of pathogenic agents including virus and bacteria. It has been shown that the presence and composition of the microbiota is directly involved in the regulation of gene transcription in the intestinal epithelium...... expression of all mucin genes are dependent on the presence of microorganisms and whether specific bacteria are capable of regulating mucus production in early life remains, however, to be established. The very first period after birth is believed to be vulnerable for establishment of the gut microbiota...... animal groups and the two different days tested, which will be presented at the meeting. This is the first study to examine effects of different colonizing bacteria on mucus related gene expression levels in new born mice. These results may thus improve our understanding of the complex interplay between...

  20. The Vat-AIEC protease promotes crossing of the intestinal mucus layer by Crohn's disease-associated Escherichia coli.

    Science.gov (United States)

    Gibold, Lucie; Garenaux, Estelle; Dalmasso, Guillaume; Gallucci, Camille; Cia, David; Mottet-Auselo, Benoit; Faïs, Tiphanie; Darfeuille-Michaud, Arlette; Nguyen, Hang Thi Thu; Barnich, Nicolas; Bonnet, Richard; Delmas, Julien

    2016-05-01

    The aetiology of Crohn's disease (CD) involves disorders in host genetic factors and intestinal microbiota. Adherent-invasive Escherichia coli (AIEC) are receiving increased attention because in studies of mucosa-associated microbiota, they are more prevalent in CD patients than in healthy subjects. AIEC are associated both with ileal and colonic disease phenotypes. In this study, we reported a protease called Vat-AIEC from AIEC that favours the mucosa colonization. The deletion of the Vat-AIEC-encoding gene resulted in an adhesion-impaired phenotype in vitro and affected the colonization of bacteria in contact with intestinal epithelial cells in a murine intestinal loop model, and also their gut colonization in vivo. Furthermore, unlike LF82Δvat-AIEC, wild-type AIEC reference strain LF82 was able to penetrate a mucus column extensively and promoted the degradation of mucins and a decrease in mucus viscosity. Vat-AIEC transcription was stimulated by several chemical conditions found in the ileum environment. Finally, the screening of E. coli strains isolated from CD patients revealed a preferential vat-AIEC association with AIEC strains belonging to the B2 phylogroup. Overall, this study revealed a new component of AIEC virulence that might favour their implantation in the gut of CD patients.

  1. Effect of grinding intensity and feed physical form on in vitro adhesion of Salmonella Typhimurium and mannose residues in intestinal mucus receptors for salmonellae.

    Science.gov (United States)

    Callies, A; Sander, S J; Verspohl, J; Beineke, A; Kamphues, J

    2012-12-01

    The hypothesis of this study was that feeding a fine, pelleted diet (FP) compared to a coarse meal diet (CM) results in a higher mannose content in the intestinal mucus of pigs and therefore an increased in vitro adhesion of Salmonella Typhimurium DT104 L to the mucus. The 2 diets were fed to a total of 24 weaned pigs for 6 wk after which mannose content in the mucus was evaluated histochemically using the α1-3-d-mannose-specific lectin Galanthus nivalis agglutinin. The crypt width was determined as an indirect measure for the amount of secreted mucus. Ileal and cecal tissue samples were incubated with approximately 7.77 × 10(7) cfu Salmonella Typhimurium and numbers of salmonellae adhering to the mucus and/or mucosa were determined by culture techniques. There was no effect of feed physical form on the in vitro adhesion of S. Typhimurium either in the ileum (7.1 ± 0.19 log(10) cfu/g tissue) or in the cecum (6.8 ± 0.26 log(10) cfu/g). The mannose content of the mucus also did not differ between the treatment groups. The crypts of the duodenum, jejunum, and cecum were wider (P < 0.05) after feeding the CM diet. This might be an indication for a higher mucus production in these pigs.

  2. Effects of mucokinetic drugs on rheological properties of reconstituted human nasal mucus.

    Science.gov (United States)

    Rhee, C S; Majima, Y; Cho, J S; Arima, S; Min, Y G; Sakakura, Y

    1999-01-01

    To investigate the effects of mucokinetic drugs on the rheological properties of human nasal mucus in patients with chronic sinusitis. We reconstituted human nasal mucus obtained from 74 patients with chronic sinusitis and determined the effects of 4 mucokinetic drugs, including acetylcysteine, deoxynuclease I, 2% sodium bicarbonate, and a combination product containing tyloxapol (Alevaire), on rheological properties of reconstituted human nasal mucus (RHNM). We used 5% RHNM dissolved in phosphate-buffered solution as the optimal buffer and concentration of RHNM for the study because it showed a viscoelastic response similar to that of freshly collected nasal mucus from patients with chronic sinusitis. Four experiments were performed to determine the influence of each drug on dynamic viscosity and elasticity of 5% RHNM. Distilled water was used as a control. Acetylcysteine and deoxynuclease I significantly decreased both dynamic viscosity and elastic modulus, while distilled water had no effect on rheological properties of 5% RHNM in vitro. Alevaire significantly reduced both dynamic viscosity and elastic modulus. Sodium bicarbonate significantly reduced elastic modulus but not dynamic viscosity. Reduction of elastic modulus by Alevaire was significantly greater than that by sodium bicarbonate, while there was no difference in reduction of dynamic viscosity between them. Our results indicate that RHNM may be useful for studying the topical effects of various drugs on nasal mucus from patients with chronic sinusitis.

  3. Dexamethasone and N-acetyl-cysteine attenuate Pseudomonas aeruginosa-induced mucus expression in human airways.

    Science.gov (United States)

    Sprenger, Lisa; Goldmann, Torsten; Vollmer, Ekkehard; Steffen, Armin; Wollenberg, Barbara; Zabel, Peter; Hauber, Hans-Peter

    2011-04-01

    Infection with Pseudomonas aeruginosa (PA) induces mucus hypersecretion in airways. Therapeutic options to attenuate excessive mucus expression are sparse. To investigate the effect of steroids and N-acetyl-cysteine (NAC) on PA-induced mucus expression. Calu-3 cells and explanted human mucosa from the upper airways were stimulated with either PA, lipopolysaccharide from alginate producing PA (smooth, sPA-LPS) or non-alginate producing PA (rough, rPA-LPS). Dexamethasone (DEX) and NAC were added in different concentrations. Expression of mucin (MUC5AC) gene and mucin protein expression was quantified using PAS (periodic acids Schiff) staining and real time PCR. PA, sPA-LPS or rPA-LPS significantly induced mucin protein and MUC5AC gene expression in Calu-3 cells and explanted mucosal tissue (P NAC significantly decreased PA-, sPA-LPS- and rPA-LPS-induced mucin protein expression both in vitro and ex vivo (P 0.05). Our data show that both an anti-inflammatory drug (DEX) and an anti-oxidative agent (NAC) can attenuate PA-induced mucus expression in human airways. These results support the use of steroids and NAC in clinical practice to treat PA-induced mucus hypersecretion. Copyright © 2010 Elsevier Ltd. All rights reserved.

  4. The Microstructure and Bulk Rheology of Human Cervicovaginal Mucus are Remarkably Resistant to Changes in pH

    OpenAIRE

    Wang, Ying-Ying; Lai, Samuel K.; Ensign, Laura; Zhong, Weixi; Cone, Richard; Hanes, Justin

    2013-01-01

    The protective barrier, lubricant and clearance functions of mucus are intimately coupled to its microstructure and bulk rheology. Mucus gels consist of a network of mucin biopolymers along with lipids, salts and other proteins, and exhibit similar biochemical and physical properties across diverse mucosal surfaces. Nevertheless, mucus is exposed to a broad range of pH throughout the human body. Protein functions are typically sensitive to small changes in pH, and prior investigations using r...

  5. In vitro growth characteristics of five candidate aquaculture probiotics and two fish pathogens grown in fish intestinal mucus.

    Science.gov (United States)

    Vine, Niall G; Leukes, Winston D; Kaiser, Horst

    2004-02-09

    The selection of probiotics for aquaculture is usually based on their antagonism towards pathogens. However, other criteria such as growth, attachment to intestinal mucus and production of beneficial compounds should also be considered. We suggest a protocol for the isolation and selection of potential probiotic bacteria based on their in vitro growth characteristics and propose a ranking index (RI) to screen potential aquaculture probionts. We suggest that the lag period and doubling time are the most important criteria for the comparison of growth curves, hence the RI is based on the doubling time (t(d)) and lag period (lambda) obtained from the growth profile of each bacterium. Bacteria were isolated from the gut of the common clownfish, Amphiprion percula, and screened for antagonistic activity towards seven aquatic pathogens. All five candidate probiotics showed antagonism to various aquatic pathogens. When grown in intestinal fish mucus no probiotic had a RI higher than the two tested pathogens (Aeromonas hydrophila and Vibrio alginolyticus). However, candidate probiont AP1 had a faster specific growth rate (micro) (0.05) than the pathogens (0.049 and 0.047 respectively), while AP5 grown in marine broth had a shorter lag period than the pathogens. Strategies to increase probiotic concentration include the inoculation of high concentrations and the preconditioning of these bacteria to reduce the lag period. It should be tested whether or not such strategies will allow the probiotic bacteria to dominate initially and thereby gain a competitive advantage. This could become an important aspect under in vivo conditions where both attachment and nutrient supply differ from that found in in vitro studies.

  6. Toward the modeling of mucus draining from the human lung: role of the geometry of the airway tree

    Science.gov (United States)

    Mauroy, Benjamin; Fausser, Christian; Pelca, Dominique; Merckx, Jacques; Flaud, Patrice

    2011-10-01

    Mucociliary clearance and cough are the two main natural mucus draining methods in the bronchial tree. If they are affected by a pathology, they can become insufficient or even ineffective, then therapeutic draining of mucus plays a critical role to keep mucus levels in the lungs acceptable. The manipulations of physical therapists are known to be very efficient clinically but they are mostly empirical since the biophysical mechanisms involved in these manipulations have never been studied. We develop in this work a model of mucus clearance in idealized rigid human bronchial trees and focus our study on the interaction between (1) tree geometry, (2) mucus physical properties and (3) amplitude of flow rate in the tree. The mucus is considered as a Bingham fluid (gel-like) which is moved upward in the tree thanks to its viscous interaction with air flow. Our studies point out the important roles played both by the geometry and by the physical properties of mucus (yield stress and viscosity). More particularly, the yield stress has to be overcome to make mucus flow. Air flow rate and yield stress determine the maximal possible mucus thickness in each branch of the tree at equilibrium. This forms a specific distribution of mucus in the tree whose characteristics are strongly related to the multi-scaled structure of the tree. The behavior of any mucus distribution is then dependent on this distribution. Finally, our results indicate that increasing air flow rates ought to be more efficient to drain mucus out of the bronchial tree while minimizing patient discomfort.

  7. The microstructure and bulk rheology of human cervicovaginal mucus are remarkably resistant to changes in pH.

    Science.gov (United States)

    Wang, Ying-Ying; Lai, Samuel K; Ensign, Laura M; Zhong, Weixi; Cone, Richard; Hanes, Justin

    2013-12-09

    The protective barrier, lubricant, and clearance functions of mucus are intimately coupled to its microstructure and bulk rheology. Mucus gels consist of a network of mucin biopolymers along with lipids, salts, and other proteins and exhibit similar biochemical and physical properties across diverse mucosal surfaces. Nevertheless, mucus is exposed to a broad range of pH values throughout the human body. Protein functions are typically sensitive to small changes in pH, and prior investigations using reconstituted, purified mucin gels suggested mucus undergoes a transition from a low-viscosity liquid at neutral pH to a highly viscoelastic solid at low pH. We sought to determine whether those observations hold for fresh, minimally perturbed human mucus ex vivo by using different-sized muco-inert nanoparticles to probe microstructure and cone-and-plate rheometry to measure bulk rheology. We demonstrate that both the microstructure and bulk rheology of fresh, undiluted, and minimally perturbed cervicovaginal mucus exhibit relatively minor changes from pH 1-2 to 8-9, in marked contrast with the pH sensitivity of purified mucin gels. Our work also suggests additional components in mucus secretions, typically eliminated during mucin purification and reconstitution, may play an important role in maintaining the protective properties of mucus.

  8. Proteomic analysis of pure human airway gland mucus reveals a large component of protective proteins.

    Directory of Open Access Journals (Sweden)

    Nam Soo Joo

    Full Text Available Airway submucosal glands contribute to innate immunity and protect the lungs by secreting mucus, which is required for mucociliary clearance and which also contains antimicrobial, anti-inflammatory, anti-proteolytic and anti-oxidant proteins. We stimulated glands in tracheal trimmings from three lung donors and collected droplets of uncontaminated mucus as they formed at the gland orifices under an oil layer. We analyzed the mucus using liquid chromatography-tandem mass spectrometry (LC-MS/MS. Analysis identified 5486 peptides and 441 proteins from across the 3 samples (269-319 proteins per subject. We focused on 269 proteins common to at least 2 0f 3 subjects, of which 102 (38% had protective or innate immunity functions. While many of these have long been known to play such roles, for many others their cellular protective functions have only recently been appreciated in addition to their well-studied biologic functions (e.g. annexins, apolipoproteins, gelsolin, hemoglobin, histones, keratins, and lumican. A minority of the identified proteins are known to be secreted via conventional exocytosis, suggesting that glandular secretion occurs via multiple mechanisms. Two of the observed protective proteins, major vault protein and prohibitin, have not been observed in fluid from human epithelial cultures or in fluid from nasal or bronchoalveolar lavage. Further proteomic analysis of pure gland mucus may help clarify how healthy airways maintain a sterile environment.

  9. The StcE metalloprotease of enterohaemorrhagic Escherichia coli reduces the inner mucus layer and promotes adherence to human colonic epithelium ex vivo.

    Science.gov (United States)

    Hews, Claire L; Tran, Seav-Ly; Wegmann, Udo; Brett, Bernard; Walsham, Alistair D S; Kavanaugh, Devon; Ward, Nicole J; Juge, Nathalie; Schüller, Stephanie

    2017-01-05

    Enterohaemorrhagic Escherichia coli (EHEC) is a major foodborne pathogen and tightly adheres to human colonic epithelium by forming attaching/effacing lesions. To reach the epithelial surface, EHEC must penetrate the thick mucus layer protecting the colonic epithelium. In this study, we investigated how EHEC interacts with the intestinal mucus layer using mucin-producing LS174T colon carcinoma cells and human colonic mucosal biopsies. The level of EHEC binding and attaching/effacing lesion formation in LS174T cells was higher compared to mucin-deficient colon carcinoma cell lines, and initial adherence was independent of the presence of flagellin, Escherichia coli common pilus, or long polar fimbriae. Although EHEC infection did not affect gene expression of secreted mucins, it resulted in reduced MUC2 glycoprotein levels. This effect was dependent on the catalytic activity of the secreted metalloprotease StcE, which reduced the inner mucus layer and thereby promoted EHEC access and binding to the epithelium in vitro and ex vivo. Given the lack of efficient therapies against EHEC infection, StcE may represent a suitable target for future treatment and prevention strategies.

  10. Loss of the intestinal mucus layer in the normal rat causes gut injury but not toxic mesenteric lymph nor lung injury.

    Science.gov (United States)

    Sharpe, Susan M; Qin, Xiaofa; Lu, Qi; Feketeova, Eleonora; Palange, David C; Dong, Wei; Sheth, Sharvil U; Lee, Marlon A; Reino, Diego; Xu, Da-Zhong; Deitch, Edwin A

    2010-11-01

    There is substantial evidence that gut barrier failure is associated with distant organ injury and systemic inflammation. After major trauma or stress, the factors and mechanisms involved in gut injury are unknown. Our primary hypothesis is that loss of the intestinal mucus layer will result in injury of the normal gut that is exacerbated by the presence of luminal pancreatic proteases. Our secondary hypothesis is that the injury produced in the gut will result in the production of biologically active mesenteric lymph and consequently distant organ (i.e., lung) injury. To test this hypothesis, five groups of rats were studied: 1) uninstrumented naive rats; 2) control rats in which a ligated segment of distal ileum was filled with saline; 3) rats with pancreatic proteases placed in their distal ileal segments; 4) rats with the mucolytic N-acetylcysteine (NAC) placed in their distal ileal segments; and 5) rats exposed to NAC and pancreatic proteases in their ileal segments. The potential systemic consequences of gut injury induced by NAC and proteases were assessed by measuring the biological activity of mesenteric lymph as well as gut-induced lung injury. Exposure of the normal intestine to NAC, but not saline or proteases, led to increased gut permeability, loss of mucus hydrophobicity, a decrease in the mucus layer, as well as morphological evidence of villous injury. Although proteases themselves did not cause gut injury, the combination of pancreatic proteases with NAC caused more severe injury than NAC alone, suggesting that once the mucus barrier is impaired, luminal proteases can injure the now vulnerable gut. Because comparable levels of gut injury caused by systemic insults are associated with gut-induced lung injury, which is mediated by biologically active factors in mesenteric lymph, we next tested whether this local model of gut injury would produce active mesenteric lymph or lead to lung injury. It did not, suggesting that gut injury by itself may not

  11. Receptor-like Molecules on Human Intestinal Epithelial Cells Interact with an Adhesion Factor from Lactobacillus reuteri

    OpenAIRE

    Matsuo, Yosuke; MIYOSHI, Yukihiro; Okada, Sanae; SATOH, Eiichi

    2012-01-01

    A surface protein of Lactobacillus reuteri, mucus adhesion-promoting protein (MapA), is considered to be an adhesion factor. MapA is expressed in L. reuteri strains and adheres to piglet gastric mucus, collagen type I, and human intestinal epithelial cells such as Caco-2. The aim of this study was to identify molecules that mediate the attachment of MapA from L. reuteri to the intestinal epithelial cell surface by investigating the adhesion of MapA to receptor-like molecules on Caco-2 cells. ...

  12. Role of intestinal mucus on the uptake of latex beads by Peyer's patches and on their transport to mesenteric lymph nodes in rats.

    Science.gov (United States)

    Khan, J; Iiboshi, Y; Cui, L; Wasa, M; Okada, A

    1999-01-01

    The effects of N-acetylcysteine (NAC) as a mucolytic agent on the uptake of fluorescent polystyrene microparticles by Peyer's patches, on intestinal permeability, and on subsequent transport to mesenteric lymph nodes (MLNs) were investigated to establish the role of mucus gel layer in this process. Twenty rats were divided into two groups: control (n = 10) and NAC (n = 10). Fluorescent polystyrene latex beads of 3.2+/-0.2 microm in diameter were used as a probe for measuring the previously mentioned parameters. The solution of latex beads (0.1 mL) was injected into a 2-cm length of ileal loop containing Peyer's patches, with 0.1 mL of saline (control group) or with 0.1 mL of NAC solution (NAC group) within 10 cm proximal from the ileocaecal valve. Intestinal loops, portal blood, and neighboring MLNs were taken within 1 hour of injection. Intestinal sections were stained by periodic acid-Schiff reagent. Peyer's patches and MLNs were analyzed for the count of particles by image analysis using a confocal laser scanning microscope. Morphologically, periodic acid-Schiff positive uniform mucus gel was present in front of Peyer's patches of the control group, and mucus gel layer was disrupted and noncontinuous in the NAC group. The number of particles within Peyer's patches and MLNs in the NAC group was significantly higher than that in the control group (pNAC group was significantly higher than that in the control group (pmucus gel layer located in front of Peyer's patches is one of the important factors for the uptake of noxious macromolecules, and this in turn plays a major role on small intestinal permeability and subsequent translocation to MLNs.

  13. Modeling the human intestinal mucin (MUC2) C-terminal cystine knot dimer.

    Science.gov (United States)

    Sadasivan, Vatsala D; Narpala, Sandeep R; Budil, David E; Sacco, Albert; Carrier, Rebecca L

    2011-11-01

    Intestinal mucus, a viscous secretion that lines the mucosa, is believed to be a barrier to absorption of many therapeutic compounds and carriers, and is known to play an important physiological role in controlling pathogen invasion. Nevertheless, there is as yet no clear understanding of the barrier properties of mucus, such as the nature of the molecular interactions between drug molecules and mucus components as well as those that govern gel formation. Secretory mucins, large and complex glycoprotein molecules, are the principal determinants of the viscoelastic properties of intestinal mucus. Despite the important role that mucins play in controlling transport and in diseases such as cystic fibrosis, their structures remain poorly characterized. The major intestinal secretory mucin gene, MUC2, has been identified and fully sequenced. The present study was undertaken to determine a detailed structure of the cysteine-rich region within the C-terminal end of human intestinal mucin (MUC2) via homology modeling, and explore possible configurations of a dimer of this cysteine-rich region, which may play an important role in governing mucus gel formation. Based on sequence-structure alignments and three-dimensional modeling, a cystine knot tertiary structure homologous to that of human chorionic gonadotropin (HCG) is predicted at the C-terminus of MUC2. Dimers of this C-terminal cystine knot (CTCK) were modeled using sequence alignment based on HCG and TGF-beta, followed by molecular dynamics and simulated annealing. Results support the formation of a cystine knot dimer with a structure analogous to that of HCG.

  14. Defense and adaptation: The complex inter-relationship between Campylobacter jejuni and mucus.

    Directory of Open Access Journals (Sweden)

    Abofu eAlemka

    2012-02-01

    Full Text Available Mucus colonization is the first step towards the establishment of infection and disease by mucosal pathogens. There is an emerging literature implicating specific mucin subtypes and mucin modifications in protecting the host from Campylobacter jejuni infection. However, mucosal pathogens have evolved sophisticated mechanisms to breach the mucus layer and C. jejuni in particular appears to harbor specific adaptations to better colonize intestinal mucus. For example, components of mucus are chemotactic for C. jejuni and the rheological properties of mucus promote motility of the organism. Furthermore, recent studies demonstrate that mucins modulate the pathogenicity of C. jejuni in a species-specific manner and likely help determine whether these bacteria become pathogenic (as in humans, or adopt a commensal mode of existence (as in chickens and other animals. This review focuses on recent advances in understanding the complex interplay between C. jejuni and components of the mucus layer.

  15. Functional Characterization of a Mucus-Specific LPXTG Surface Adhesin from Probiotic Lactobacillus rhamnosus GG ▿

    Science.gov (United States)

    von Ossowski, Ingemar; Satokari, Reetta; Reunanen, Justus; Lebeer, Sarah; De Keersmaecker, Sigrid C. J.; Vanderleyden, Jos; de Vos, Willem M.; Palva, Airi

    2011-01-01

    In spite of the wealth of clinical evidence supporting the health benefits of Lactobacillus rhamnosus GG in humans, there is still a lack of understanding of the molecular mechanisms behind its probiosis. Current knowledge suggests that the health-promoting effects of this probiotic strain might be partly dependent on its persistence in the intestine and adhesion to mucosal surfaces. Moreover, L. rhamnosus GG contains mucus-binding pili that might also explain the occupation of its ecological niche as a comparatively less stringent allochthonous intestine-dwelling bacterium. To uncover additional surface proteins involved in mucosal adhesion, we investigated the adherence properties of the only predicted protein (LGG_02337) in L. rhamnosus GG that exhibits homology with a known mucus-binding domain. We cloned a recombinant form of the gene for this putative mucus adhesin and established that the purified protein readily adheres to human intestinal mucus. We also showed that this mucus adhesin is visibly distributed throughout the cell surface and participates in the adhesive interaction between L. rhamnosus GG and mucus, although less prominently than the mucus-binding pili in this strain. Based on primary structural comparisons, we concluded that the current annotation of the LGG_02337 protein likely does not accurately reflect its predicted properties, and we propose that this mucus-specific adhesin be called the mucus-binding factor (MBF). Finally, we interpret our results to mean that L. rhamnosus GG MBF, as an active mucus-specific surface adhesin with a presumed ancillary involvement in pilus-mediated mucosal adhesion, plays a part in the adherent mechanisms during intestinal colonization by this probiotic. PMID:21602388

  16. Functional characterization of a mucus-specific LPXTG surface adhesin from probiotic Lactobacillus rhamnosus GG.

    Science.gov (United States)

    von Ossowski, Ingemar; Satokari, Reetta; Reunanen, Justus; Lebeer, Sarah; De Keersmaecker, Sigrid C J; Vanderleyden, Jos; de Vos, Willem M; Palva, Airi

    2011-07-01

    In spite of the wealth of clinical evidence supporting the health benefits of Lactobacillus rhamnosus GG in humans, there is still a lack of understanding of the molecular mechanisms behind its probiosis. Current knowledge suggests that the health-promoting effects of this probiotic strain might be partly dependent on its persistence in the intestine and adhesion to mucosal surfaces. Moreover, L. rhamnosus GG contains mucus-binding pili that might also explain the occupation of its ecological niche as a comparatively less stringent allochthonous intestine-dwelling bacterium. To uncover additional surface proteins involved in mucosal adhesion, we investigated the adherence properties of the only predicted protein (LGG_02337) in L. rhamnosus GG that exhibits homology with a known mucus-binding domain. We cloned a recombinant form of the gene for this putative mucus adhesin and established that the purified protein readily adheres to human intestinal mucus. We also showed that this mucus adhesin is visibly distributed throughout the cell surface and participates in the adhesive interaction between L. rhamnosus GG and mucus, although less prominently than the mucus-binding pili in this strain. Based on primary structural comparisons, we concluded that the current annotation of the LGG_02337 protein likely does not accurately reflect its predicted properties, and we propose that this mucus-specific adhesin be called the mucus-binding factor (MBF). Finally, we interpret our results to mean that L. rhamnosus GG MBF, as an active mucus-specific surface adhesin with a presumed ancillary involvement in pilus-mediated mucosal adhesion, plays a part in the adherent mechanisms during intestinal colonization by this probiotic.

  17. The effects of feeding with synbiotic (Pediococcus acidilactici and fructooligosaccharide) enriched adult Artemia on skin mucus immune responses, stress resistance, intestinal microbiota and performance of angelfish (Pterophyllum scalare).

    Science.gov (United States)

    Azimirad, Mahmood; Meshkini, Saeed; Ahmadifard, Nasrollah; Hoseinifar, Seyed Hossein

    2016-07-01

    The aim of this study was to evaluate the effects of feeding on synbiotic (Pediococcus acidilactici and fructooligosaccharide) enriched adult Artemia franciscana on skin mucus immune responses, stress resistance, intestinal microbiota and growth performance of angelfish (Pterophyllum scalare). Three hundred and sixty fish with initial weight 3.2 ± 0.13 g were randomly divided into twelve aquaria (50 L) assigned to four groups in triplicates. Fish were fed for 7 weeks with dietary treatments, including treatment 1: feeding adult Artemia without enrichment (control group), treatment 2: feeding adult Artemia enriched with lyophilised probiotic P. acidilactici (700 mg L(-1)), 3: feeding adult Artemia enriched with prebiotic fructooligosaccharide (FOS) (100 mg L(-1)), group 4: feeding adult Artemia enriched with synbiotic (P. acidilactici (700 mg L(-1)) + FOS (100 mg L(-1))). Skin mucus immune responses (lysozyme activity, total Immunoglobulin and protease), stress resistance against environmental stress (acute decrease of temperature and increase salinity), intestinal microbiota as well as growth indices were measured at the end of feeding trial. Artemia enriched with synbiotic significantly improved growth performance compared to other treatments (P Artemia enriched with synbiotic (P Artemia was more effective than singular enrichment with probiotics or prebiotics.

  18. Association between the ABO blood group and the human intestinal microbiota composition

    Directory of Open Access Journals (Sweden)

    Mäkivuokko Harri

    2012-06-01

    Full Text Available Abstract Background The mucus layer covering the human intestinal epithelium forms a dynamic surface for host-microbial interactions. In addition to the environmental factors affecting the intestinal equilibrium, such as diet, it is well established that the microbiota composition is individually driven, but the host factors determining the composition have remained unresolved. Results In this study, we show that ABO blood group is involved in differences in relative proportion and overall profiles of intestinal microbiota. Specifically, the microbiota from the individuals harbouring the B antigen (secretor B and AB differed from the non-B antigen groups and also showed higher diversity of the Eubacterium rectale-Clostridium coccoides (EREC and Clostridium leptum (CLEPT -groups in comparison with other blood groups. Conclusions Our novel finding indicates that the ABO blood group is one of the genetically determined host factors modulating the composition of the human intestinal microbiota, thus enabling new applications in the field of personalized nutrition and medicine.

  19. The use of hens' egg white as a substitute for human cervical mucus in assessing human infertility.

    Science.gov (United States)

    Eggert-Kruse, W; Gerhard, I; Tilgen, W; Runnebaum, B

    1990-08-01

    Semen samples from 179 patients with longstanding infertility were allowed to penetrate capillaries filled with a fraction of fresh hens' egg white (HEW) as a substitute for cervical mucus (CM) for the in-vitro sperm-cervical mucus penetration test (SCPMT). Results were correlated with those obtained from human CM (HCM) used in parallel on the same semen sample, compared to results of sperm analysis and post-coital testing (PCT) and analysed for their prognostic value for a subsequent pregnancy in a prospective study. The overall pregnancy rate after 6 months was 26.3% (47/179). Whereas routine semen analysis (semen volume, pH, sperm count, progressive motility, morphology and fructose concentration) did not differentiate between patients who achieved pregnancy and those who did not, significant differences were found for the penetration distance (P less than 0.02) and the motility grade of sperm in HEW (P less than 0.02). Although the mean sperm velocity in HEW was reduced compared to HCM, a close positive correlation was found between the sperm density and the penetration distance (P less than 0.001). The percentage of samples with good HEW penetration increased significantly in parallel with better results of post-coital testing (P less than 0.001). The results indicate that, when fresh human CM is not available, HEW can be used as a medium for the SCPMT as a valuable adjunct to semen analysis which provides information about sperm functional capacity.

  20. Microbial functionality in the human intestinal tract

    NARCIS (Netherlands)

    Salonen, A.; Palva, A.; Vos, de W.M.

    2009-01-01

    The extent of metabolic interactions between symbiotic intestinal microbes and the human host, and their system-wide effects on the host physiology are beginning to be understood. The metabolic capacity encoded by the intestinal microbiome significantly extends that of the host, making many of man's

  1. The inhibition of the Human Immunodeficiency Virus type 1 activity by crude and purified human pregnancy plug mucus and mucins in an inhibition assay

    Directory of Open Access Journals (Sweden)

    Schoeman Leann

    2008-05-01

    Full Text Available Abstract Background The female reproductive tract is amongst the main routes for Human Immunodeficiency Virus (HIV transmission. Cervical mucus however is known to protect the female reproductive tract from bacterial invasion and fluid loss and regulates and facilitates sperm transport to the upper reproductive tract. The purpose of this study was to purify and characterize pregnancy plug mucins and determine their anti-HIV-1 activity in an HIV inhibition assay. Methods Pregnancy plug mucins were purified by caesium chloride density-gradient ultra-centrifugation and characterized by Western blotting analysis. The anti-HIV-1 activities of the crude pregnancy plug mucus and purified pregnancy plug mucins was determined by incubating them with HIV-1 prior to infection of the human T lymphoblastoid cell line (CEM SS cells. Results The pregnancy plug mucus had MUC1, MUC2, MUC5AC and MUC5B. The HIV inhibition assay revealed that while the purified pregnancy plug mucins inhibit HIV-1 activity by approximately 97.5%, the crude pregnancy plug mucus failed to inhibit HIV-1 activity. Conclusion Although it is not clear why the crude sample did not inhibit HIV-1 activity, it may be that the amount of mucins in the crude pregnancy plug mucus (which contains water, mucins, lipids, nucleic acids, lactoferrin, lysozyme, immunoglobulins and ions, is insufficient to cause viral inhibition or aggregation.

  2. Mechanism of Human Influenza Virus RNA Persistence and Virion Survival in Feces: Mucus Protects Virions From Acid and Digestive Juices.

    Science.gov (United States)

    Hirose, Ryohei; Nakaya, Takaaki; Naito, Yuji; Daidoji, Tomo; Watanabe, Yohei; Yasuda, Hiroaki; Konishi, Hideyuki; Itoh, Yoshito

    2017-07-01

    Although viral RNA or infectious virions have been detected in the feces of individuals infected with human influenza A and B viruses (IAV/IBV), the mechanism of viral survival in the gastrointestinal tract remains unclear. We developed a model that attempts to recapitulate the conditions encountered by a swallowed virus. While IAV/IBV are vulnerable to simulated digestive juices (gastric acid and bile/pancreatic juice), highly viscous mucus protects viral RNA and virions, allowing the virus to retain its infectivity. Our results suggest that virions and RNA present in swallowed mucus are not inactivated or degraded by the gastrointestinal environment, allowing their detection in feces. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.

  3. An investigation into the role of mucus thickness on mucoadhesion in the gastrointestinal tract of pig.

    Science.gov (United States)

    Varum, Felipe J O; Veiga, Francisco; Sousa, João S; Basit, Abdul W

    2010-07-11

    Mucoadhesion in the gastrointestinal tract is a complex phenomenon and both formulation and physiological features need to be well understood and considered. Mucus thickness has been inferred to play a role in this process; however no definitive influence has been established. This study aimed to investigate the influence of mucus thickness on the mucoadhesion process, using a large animal (pig) as a model to closely resemble the human physiological features. The mucus thickness of different regions of the gastrointestinal tract of pig was fully measured by means of a histochemical method (hematoxilin/eosin) employing cryostat sections. Mucoadhesion was evaluated ex vivo on porcine mucosa by tensiometry using a polyacrylic acid polymer (Carbopol 974P NF) as a mucoadhesive model material, both in a dry and swollen state. Mucus was thickest in the stomach (body 67.9+/-54.7 microm) and mucus thickness increased from proximal to distal segments in both the small intestine (duodenum 25.9+/-11.8 microm, ileum 31.0+/-15.7 microm) and large intestine (caecum 19.4+/-8.7 microm, ascending colon 31.9+/-17.2 microm, descending colon 35.1+/-16.0 microm and rectum 40.8+/-12.5 microm). Swollen polymer exhibited lower mucoadhesion than the dry form in all sections analysed. Mucus thickness plays a role on the mucoadhesion, as thicker mucus provides deeper polymer chain diffusion and entanglements; however, other factors are also involved in this complex process.

  4. Species and prevalence determination of Human Intestinal ...

    African Journals Online (AJOL)

    ADOWIE PERE

    Species and prevalence determination of Human Intestinal Parasites among Patients attending two ... the maintenance of proper personal hygiene, creating awareness to the ..... (2007), who reported a value of 21.1% in Owerri,. Imo State and ...

  5. Comparative genomic analysis of Lactobacillus rhamnosus GG reveals pili containing a human- mucus binding protein

    NARCIS (Netherlands)

    Kankainen, M.; Paulin, L.; Tynkkynen, S.; Ossowski, von I.; Reunanen, J.; Partanen, P.; Satokari, A.; Vesterlund, S.; Hendrickx, A.P.; Lebeer, S.; Keersmaecker, de S.C.; Vanderleyden, J.; Hämäläinen, T.; Laukkanen, S.; Salovuori, N.; Ritari, J.; Alatalo, E.; Korpela, R.; Mattila-Sandholm, T.; Lassig, A.; Hatakka, K.; Kinnunen, K.T.; Karjalainen, H.; Saxelin, M.; Laakso, K.; Surakka, A.; Palva, A.; Salusjärvi, T.; Auvinen, P.; Vos, de W.M.

    2009-01-01

    To unravel the biological function of the widely used probiotic bacterium Lactobacillus rhamnosus GG, we compared its 3.0-Mbp genome sequence with the similarly sized genome of L. rhamnosus LC705, an adjunct starter culture exhibiting reduced binding to mucus. Both genomes demonstrated high sequence

  6. Human intestinal capillariasis in Thailand

    Institute of Scientific and Technical Information of China (English)

    Prasert Saichua; Choosak Nithikathkul; Natthawut Kaewpitoon

    2008-01-01

    Intestinal capillariasis caused by Capillaria philippinensis appeared first in the Philippines and subsequently in Thailand, Japan, Iran, Egypt and Taiwan; major outbreaks have occurred in the Philippines and Thailand. This article reviews the epidemiology, history and sources of C. philippinensis infection in Thailand. The annual epidemiological surveillance reports indicated that 82 accumulated cases of intestinal capillariasis were found in Thailand from 1994-2006. That made Thailand a Capillaria-prevalent area. Sisaket, in northeast Thailand, was the first province which has reported intestinal capillariasis. Moreover, Buri Ram presented a high prevalence of intestinal capillariasis, totaling 24 cases from 1994-2006. About half of all cases have consumed raw or undercooked fish. However, even if the numbers of the intestinal capillariasis cases in Thailand is reduced, C. philippinensis infection cases are still reported. The improvement of personal hygiene, specifically avoiding consumption of undercooked fish and promoting a health education campaign are required. These strategies may minimize or eliminate C. philippinensis infection in Thailand.

  7. Human milk oligosaccharide consumption by intestinal microbiota

    OpenAIRE

    Marcobal, A.; Sonnenburg, J L

    2012-01-01

    Human milk oligosaccharides (HMO) constitute the third most abundant class of molecules in breast milk. Since infants lack the enzymes required for milk glycan digestion, this group of carbohydrates passes undigested to the lower part of the intestinal tract, where they can be consumed by specific members of the infant gut microbiota. We review proposed mechanisms for the depletion and metabolism of HMO by two major bacterial genera within the infant intestinal microbiota, Bifidobacterium and...

  8. R1: Immunohistochemical study of mucins in human intestinal spirochetosis.

    Science.gov (United States)

    Ogata, Sho; Shimizu, Ken; Tominaga, Susumu; Nakanishi, Kuniaki

    2017-02-08

    Most patients with human intestinal spirochetosis (HIS; a colorectal bacterial infection caused by Brachyspira species) seem asymptomatic, and its pathogenicity remains unclear. Recently, alterations in mucin expression were reported in animal Brachyspira infection. The present question was "Is mucin expression altered in HIS?". Using antibodies for MUCs 1, 2, 4, 5 AC, and 6, we immunohistochemically compared 215 specimens from 83 histology-confirmed HIS cases with 106 specimens from 26 non-HIS cases. Positive staining (which included even focal positive staining) was rated "high (+)" or "low (+)". Results were analysed for four categories of lesions, and associations between MUC expression and spirochetal presence were also analysed. In the "specimens without polyps or adenocarcinoma" category: high (+) MUC2-positivity was more frequent in HIS than in control. In the hyperplasia/serrated polyp category: in HIS (vs. control), the MUC5AC-positivity rate was lower, while high (+) MUC4-positivity was more frequent. In the conventional adenoma category: in HIS (vs. control), the MUC1-positivity rate was lower, while both high (+) MUC2-positivity and high (+) MUC5AC-positivity were less frequent. In the adenocarcinoma category: high (+) MUC2-positivity was more frequent in HIS than in control. Among the above mucins, only MUC1-positivity was significantly associated with an absence of the so-called fringe formation, an absence of spiral organisms within mucus, and an absence of strong immunopositive materials within the epithelial layer and within the subepithelial layer. The results suggest that Brachyspira infection or a related change in the microbiome may alter the large intestine mucin-expression profile in humans.

  9. Human sperm quality and lipid content after migration into normal ovulatory human cervical mucus containing low numbers of leukocytes

    Institute of Scientific and Technical Information of China (English)

    Nozha Chakroun-Feki; Patrice Therond; Martine Couturier; Florence Eustache; Gerard Limea; Alain Legrand; Pierre Jouannet; Jacques Auger

    2009-01-01

    The aim of this study was to investigate whether a relationship exists between the presence of low number of leukocytes in normal ovulatory cervical mucus and sperm quality and lipid content after migration. The percentages of live, motile and morphologically normal spermatozoa, movement parameters assessed by computer-aided sperm analysis (CASA), and ionophore-induced acrosome reaction measured by flow cytometry were determined before and after migration. High-performance liquid chromatography with ultraviolet detection was used to measure the sperm lipid content, including the various diacyl subspecies. The number of leukocytes found in solubilized mucus samples was counted using a haemocytometric method. Overall, the presence of leukocytes in the cervical mucus samples did not significantly influence sperm motility and morphology, sperm kinematic parameters, or the sperm content in sphingomyelin or cholesterol. In contrast, after migration, the decrease in various sperm diacyls and the level of induced acrosome reaction was significantly less pronounced in mucus samples containing ≥ 104 leukocytes than in mucus samples with no or rare leukocytes whereas the level of induced acrosome reaction was higher. The present data suggest that the low level of leukocytes found in normal ovulatory cervical mucus could influence the process of sperm lipid remodelling/capacitation.

  10. A Dietary Fiber-Deprived Gut Microbiota Degrades the Colonic Mucus Barrier and Enhances Pathogen Susceptibility.

    Science.gov (United States)

    Desai, Mahesh S; Seekatz, Anna M; Koropatkin, Nicole M; Kamada, Nobuhiko; Hickey, Christina A; Wolter, Mathis; Pudlo, Nicholas A; Kitamoto, Sho; Terrapon, Nicolas; Muller, Arnaud; Young, Vincent B; Henrissat, Bernard; Wilmes, Paul; Stappenbeck, Thaddeus S; Núñez, Gabriel; Martens, Eric C

    2016-11-17

    Despite the accepted health benefits of consuming dietary fiber, little is known about the mechanisms by which fiber deprivation impacts the gut microbiota and alters disease risk. Using a gnotobiotic mouse model, in which animals were colonized with a synthetic human gut microbiota composed of fully sequenced commensal bacteria, we elucidated the functional interactions between dietary fiber, the gut microbiota, and the colonic mucus barrier, which serves as a primary defense against enteric pathogens. We show that during chronic or intermittent dietary fiber deficiency, the gut microbiota resorts to host-secreted mucus glycoproteins as a nutrient source, leading to erosion of the colonic mucus barrier. Dietary fiber deprivation, together with a fiber-deprived, mucus-eroding microbiota, promotes greater epithelial access and lethal colitis by the mucosal pathogen, Citrobacter rodentium. Our work reveals intricate pathways linking diet, the gut microbiome, and intestinal barrier dysfunction, which could be exploited to improve health using dietary therapeutics.

  11. Discovery of low mucus adhesion surfaces.

    Science.gov (United States)

    Gu, Minghao; Yildiz, Hasan; Carrier, Rebecca; Belfort, Georges

    2013-02-01

    Mucus secretion from the body is ubiquitous, and finding materials that resist mucus adhesion is a major technological challenge. Here, using a high throughput platform with photo-induced graft polymerization, we first rapidly synthesized, screened and tested a library of 55 different surfaces from six functional monomer classes to discover porcine intestinal low mucus adhesion surfaces using a 1h static mucus adsorption protocol. From this preliminary screen, two chemistries, a zwitterionic ([2-(acryloyloxy)ethyl] trimethylammonium chloride) and a multiple hydroxyl (N-[tris(hydroxymethyl)methyl]acrylamide) surface, exhibited significantly low mucus adhesion from a Langmuir-type isotherm when exposed to increasing concentrations of mucus for 24 h. Apolar or hydrophobic interactions were likely the dominant attractive forces during mucus binding since many polar or hydrophilic monomers reduced mucus adhesion. Hansen solubility parameters were used to illustrate the importance of monomer polarity and hydrogen bonding in reducing mucus adsorption. For a series of polyethylene glycol (PEG) monomers with changing molecular weight from 144 g mol⁻¹ to 1100 g mol⁻¹, we observed an excellent linear correlation (R²=0.998) between relative amount adsorbed and the distance from a water point in a specialized Hansen solubility parameter plot, emphasizing the role of surface-water interactions for PEG modified surfaces.

  12. [Variation of the sialic acid-protein ratio in the human cervical mucus (author's transl)].

    Science.gov (United States)

    Kesserü, E; Westphal, N

    1975-01-01

    Serial determinations of total protein and sialic acid concentrations were carried out in individual cervical mucus samples of normal women, throughout the menstrual cycle as well as under the influence of estrogen and progestagen steroids. Total protein was titrated by a modified micro-biuret method and sialic acid was determined using the "Direct Ehrlich" method. Both parameters diminished gradually during the follicular phase of the cycle with lowest values around the time of ovulation, and showed a strong increase during the luteal phase. Administration of ethinylestradiol yielded values significantly lower than those of normal ovulatory phase and under d-Nosgestrel treatment the values were significantly higher than in normal luteal phase. However the proportion of sialic acid as related to total protein showed an inverse behavior, i.e. increased under estrogenic and decreased under progestogenic influence. The cyclic and hormone-induced variations of this ratio were more specific than those of both separate components. Thus, estrogens produce an increase of the sialic acid containing fraction of cervical mucus proteins, while progestagens have an opposite effect. The role of these actions in reproductive physiology is discussed.

  13. Faecalibacterium prausnitzii and human intestinal health

    NARCIS (Netherlands)

    Miquel, S.; Martin, R.; Rossi, O.; Bermudez-Humaran, L.G.; Chatel, J.M.; Sokol, H.; Thomas, M.; Wells, J.M.; Langella, P.

    2013-01-01

    Faecalibacterium prausnitzii is the most abundant bacterium in the human intestinal microbiota of healthy adults, representing more than 5% of the total bacterial population. Over the past five years, an increasing number of studies have clearly described the importance of this highly metabolically

  14. Faecalibacterium prausnitzii and human intestinal health

    NARCIS (Netherlands)

    Miquel, S.; Martin, R.; Rossi, O.; Bermudez-Humaran, L.G.; Chatel, J.M.; Sokol, H.; Thomas, M.; Wells, J.M.; Langella, P.

    2013-01-01

    Faecalibacterium prausnitzii is the most abundant bacterium in the human intestinal microbiota of healthy adults, representing more than 5% of the total bacterial population. Over the past five years, an increasing number of studies have clearly described the importance of this highly metabolically

  15. Bronchial mucus transport

    NARCIS (Netherlands)

    van der Schans, Cees P.

    2007-01-01

    Effective clearance of inhaled particles requires mucus production and continuous mucus transport from the lower airways to the oropharynx. Mucus production takes place mainly in the peripheral airways. Mucus transport is achieved by the action of the ciliated cells that cover the inner surface of t

  16. Novel mucus-penetrating liposomes as a potential oral drug delivery system

    DEFF Research Database (Denmark)

    Li, Xiuying; Chen, Dan; Le, Chaoyi

    2011-01-01

    The aim of this study was to investigate the intestinal mucus-penetrating properties and intestinal cellular uptake of two types of liposomes modified by Pluronic F127 (PF127).......The aim of this study was to investigate the intestinal mucus-penetrating properties and intestinal cellular uptake of two types of liposomes modified by Pluronic F127 (PF127)....

  17. An ex-vivo human intestinal model to study Entamoeba histolytica pathogenesis.

    Directory of Open Access Journals (Sweden)

    Devendra Bansal

    Full Text Available Amoebiasis (a human intestinal infection affecting 50 million people every year is caused by the protozoan parasite Entamoeba histolytica. To study the molecular mechanisms underlying human colon invasion by E. histolytica, we have set up an ex vivo human colon model to study the early steps in amoebiasis. Using scanning electron microscopy and histological analyses, we have established that E. histolytica caused the removal of the protective mucus coat during the first two hours of incubation, detached the enterocytes, and then penetrated into the lamina propria by following the crypts of Lieberkühn. Significant cell lysis (determined by the release of lactodehydrogenase and inflammation (marked by the secretion of pro-inflammatory molecules such as interleukin 1 beta, interferon gamma, interleukin 6, interleukin 8 and tumour necrosis factor were detected after four hours of incubation. Entamoeba dispar (a closely related non-pathogenic amoeba that also colonizes the human colon was unable to invade colonic mucosa, lyse cells or induce an inflammatory response. We also examined the behaviour of trophozoites in which genes coding for known virulent factors (such as amoebapores, the Gal/GalNAc lectin and the cysteine protease 5 (CP-A5, which have major roles in cell death, adhesion (to target cells or mucus and mucus degradation, respectively were silenced, together with the corresponding tissue responses. Our data revealed that the signalling via the heavy chain Hgl2 or via the light chain Lgl1 of the Gal/GalNAc lectin is not essential to penetrate the human colonic mucosa. In addition, our study demonstrates that E. histolytica silenced for CP-A5 does not penetrate the colonic lamina propria and does not induce the host's pro-inflammatory cytokine secretion.

  18. An ex-vivo human intestinal model to study Entamoeba histolytica pathogenesis.

    Science.gov (United States)

    Bansal, Devendra; Ave, Patrick; Kerneis, Sophie; Frileux, Pascal; Boché, Olivier; Baglin, Anne Catherine; Dubost, Geneviève; Leguern, Anne-Sophie; Prevost, Marie-Christine; Bracha, Rivka; Mirelman, David; Guillén, Nancy; Labruyère, Elisabeth

    2009-11-17

    Amoebiasis (a human intestinal infection affecting 50 million people every year) is caused by the protozoan parasite Entamoeba histolytica. To study the molecular mechanisms underlying human colon invasion by E. histolytica, we have set up an ex vivo human colon model to study the early steps in amoebiasis. Using scanning electron microscopy and histological analyses, we have established that E. histolytica caused the removal of the protective mucus coat during the first two hours of incubation, detached the enterocytes, and then penetrated into the lamina propria by following the crypts of Lieberkühn. Significant cell lysis (determined by the release of lactodehydrogenase) and inflammation (marked by the secretion of pro-inflammatory molecules such as interleukin 1 beta, interferon gamma, interleukin 6, interleukin 8 and tumour necrosis factor) were detected after four hours of incubation. Entamoeba dispar (a closely related non-pathogenic amoeba that also colonizes the human colon) was unable to invade colonic mucosa, lyse cells or induce an inflammatory response. We also examined the behaviour of trophozoites in which genes coding for known virulent factors (such as amoebapores, the Gal/GalNAc lectin and the cysteine protease 5 (CP-A5), which have major roles in cell death, adhesion (to target cells or mucus) and mucus degradation, respectively) were silenced, together with the corresponding tissue responses. Our data revealed that the signalling via the heavy chain Hgl2 or via the light chain Lgl1 of the Gal/GalNAc lectin is not essential to penetrate the human colonic mucosa. In addition, our study demonstrates that E. histolytica silenced for CP-A5 does not penetrate the colonic lamina propria and does not induce the host's pro-inflammatory cytokine secretion.

  19. Modeling and Simulation of Mucus Flow in Human Bronchial Epithelial Cell Cultures - Part I: Idealized Axisymmetric Swirling Flow.

    Science.gov (United States)

    Vasquez, Paula A; Jin, Yuan; Palmer, Erik; Hill, David; Forest, M Gregory

    2016-08-01

    A multi-mode nonlinear constitutive model for mucus is constructed directly from micro- and macro-rheology experimental data on cell culture mucus, and a numerical algorithm is developed for the culture geometry and idealized cilia driving conditions. This study investigates the roles that mucus rheology, wall effects, and HBE culture geometry play in the development of flow profiles and the shape of the air-mucus interface. Simulations show that viscoelasticity captures normal stress generation in shear leading to a peak in the air-mucus interface at the middle of the culture and a depression at the walls. Linear and nonlinear viscoelastic regimes can be observed in cultures by varying the hurricane radius and mean rotational velocity. The advection-diffusion of a drug concentration dropped at the surface of the mucus flow is simulated as a function of Peclet number.

  20. Mucin dynamics in the chick small intestine are altered by starvation.

    Science.gov (United States)

    Smirnov, Asya; Sklan, David; Uni, Zehava

    2004-04-01

    The absorptive surface of the small intestine is covered by a layer of mucus secreted by goblet cells. The secreted mucins and thickness of the adherent layer influence nutrient digestion and absorption processes as well as the functionality of the mucosa. In this study, methods for the analysis of mucin synthesis and dynamics in the chick small intestine are described. A fragment of chicken mucin cDNA was isolated and characterized; this fraction had 60% homology to human mucin MUC-5AC. The thickness of the mucus adherent layer and the relative amounts of mucin glycoprotein and mRNA were also examined in the small intestines of control and starved chicks. Relative amounts of intestinal mucin mRNA and protein increased in the duodenum and jejunum of starved chicks, and mucus adherent layer thickness decreased throughout the small intestine. In starved chicks, higher mRNA expression and protein concentrations with lower amounts of adherent mucus may be related to a higher rate of degradation of the mucus layer, a lower rate of mucus secretion, or an altered rate of mucin turnover. It thus appears that starvation alters mucus dynamics in the small intestine, and this may affect intestinal digestive function and defense.

  1. Diversity of human small intestinal Streptococcus and Veillonella populations

    NARCIS (Netherlands)

    Bogert, B. van den; Erkus, O.; Boekhorst, J.; Goffau, M. de; Smid, E.J.; Zoetendal, E.G.; Kleerebezem, M.

    2013-01-01

    Molecular and cultivation approaches were employed to study the phylogenetic richness and temporal dynamics of Streptococcus and Veillonella populations in the small intestine. Microbial profiling of human small intestinal samples collected from four ileostomy subjects at four time points displayed

  2. Adhesion of enteropathogenic Escherichia coli to human intestinal enterocytes and cultured human intestinal mucosa.

    OpenAIRE

    1987-01-01

    The adhesion of classic enteropathogenic Escherichia coli (EPEC) strains of human origin to isolated human small intestinal enterocytes and cultured small intestinal mucosa was investigated. An adhesion assay with isolated human enterocytes prepared from duodenal biopsy samples was developed and tested with EPEC strains known to cause diarrhea in healthy adult volunteers. In the assay a mean of 53 and 55% of enterocytes had brush border-adherent E. coli E2348 (O127;H6) and E851 (O142:H6), res...

  3. Intestinal subepithelial myofibroblasts support in vitro and in vivo growth of human small intestinal epithelium.

    Directory of Open Access Journals (Sweden)

    Nicholas Lahar

    Full Text Available The intestinal crypt-niche interaction is thought to be essential to the function, maintenance, and proliferation of progenitor stem cells found at the bases of intestinal crypts. These stem cells are constantly renewing the intestinal epithelium by sending differentiated cells from the base of the crypts of Lieberkühn to the villus tips where they slough off into the intestinal lumen. The intestinal niche consists of various cell types, extracellular matrix, and growth factors and surrounds the intestinal progenitor cells. There have recently been advances in the understanding of the interactions that regulate the behavior of the intestinal epithelium and there is great interest in methods for isolating and expanding viable intestinal epithelium. However, there is no method to maintain primary human small intestinal epithelium in culture over a prolonged period of time. Similarly no method has been published that describes isolation and support of human intestinal epithelium in an in vivo model. We describe a technique to isolate and maintain human small intestinal epithelium in vitro from surgical specimens. We also describe a novel method to maintain human intestinal epithelium subcutaneously in a mouse model for a prolonged period of time. Our methods require various growth factors and the intimate interaction between intestinal sub-epithelial myofibroblasts (ISEMFs and the intestinal epithelial cells to support the epithelial in vitro and in vivo growth. Absence of these myofibroblasts precluded successful maintenance of epithelial cell formation and proliferation beyond just a few days, even in the presence of supportive growth factors. We believe that the methods described here can be used to explore the molecular basis of human intestinal stem cell support, maintenance, and growth.

  4. Assessment of mucus thickness and production in situ.

    Science.gov (United States)

    Holm, Lena; Phillipson, Mia

    2012-01-01

    The nature of the mucus gel layer covering the gastrointestinal tract makes it difficult to study outside its natural site attached to the mucosa. Here, we describe a technique for intravital microscopy studies of the mucus gel layer from the stomach down to the colon in anesthetized rats and mice. Mucus thickness and accumulation rate in each segment of the gastrointestinal tract is measured with a micropipette technique under observation through a stereomicroscope. In this way, the nature of the mucus gel in vivo is readily studied, and effects of interventions or disease on the mucus can be determined in longitudinal studies or by comparing animals. Using this technique, we have been able to demonstrate that there are two forms of mucus gel adherent to the stomach and colon mucosa: one layer which is removable by suction and an underlying firm adherent gel layer, while in the small intestine, all mucus adhering to the mucosa can easily be removed.

  5. Chronic mucus hypersecretion

    DEFF Research Database (Denmark)

    Ulrik, Charlotte Suppli; von Linstow, Marie-Louise; Nepper-Christensen, Steen;

    2005-01-01

    To investigate if chronic mucus hypersecretion (CMH) can be used as a marker of asthma in young adults.......To investigate if chronic mucus hypersecretion (CMH) can be used as a marker of asthma in young adults....

  6. A novel method for the culture and polarized stimulation of human intestinal mucosa explants.

    Science.gov (United States)

    Tsilingiri, Katerina; Sonzogni, Angelica; Caprioli, Flavio; Rescigno, Maria

    2013-05-01

    Few models currently exist to realistically simulate the complex human intestine's micro-environment, where a variety of interactions take place. Proper homeostasis directly depends on these interactions, as they shape an entire immunological response inducing tolerance against food antigens while at the same time mounting effective immune responses against pathogenic microbes accidentally ingested with food. Intestinal homeostasis is preserved also through various complex interactions between the microbiota (including food-associated beneficial bacterial strains) and the host, that regulate the attachment/degradation of mucus, the production of antimicrobial peptides by the epithelial barrier, and the "education" of epithelial cells' that controls the tolerogenic or immunogenic phenotype of unique, gut-resident lymphoid cells' populations. These interactions have been so far very difficult to reproduce with in vitro assays using either cultured cell lines or peripheral blood mononuclear cells. In addition, mouse models differ substantially in components of the intestinal mucosa (mucus layer organization, commensal bacteria community) with respect to the human gut. Thus, studies of a variety of treatments to be brought in the clinics for important stress-related or pathological conditions such as irritable bowel syndrome, inflammatory bowel disease or colorectal cancer have been difficult to carry out. To address these issues, we developed a novel system that enables us to stimulate explants of human intestinal mucosa that retain their in situ conditioning by the host microbiota and immune response, in a polarized fashion. Polarized apical stimulation is of great importance for the outcome of the elicited immune response. It has been repeatedly shown that the same stimuli can produce completely different responses when they bypass the apical face of the intestinal epithelium, stimulating epithelial cells basolaterally or coming into direct contact with lamina

  7. Alternative Functional In Vitro Models of Human Intestinal Epithelia

    Directory of Open Access Journals (Sweden)

    Amanda L Kauffman

    2013-07-01

    Full Text Available Physiologically relevant sources of absorptive intestinal epithelial cells are crucial for human drug transport studies. Human adenocarcinoma-derived intestinal cell lines, such as Caco-2, offer conveniences of easy culture maintenance and scalability, but do not fully recapitulate in vivo intestinal phenotypes. Additional sources of renewable physiologically relevant human intestinal cells would provide a much needed tool for drug discovery and intestinal physiology. We sought to evaluate and compare two alternative sources of human intestinal cells, commercially available primary human intestinal epithelial cells (hInEpCs and induced pluripotent stem cell (iPSC-derived intestinal cells to Caco-2, for use in in vitro transwell monolayer intestinal transport assays. To achieve this for iPSC-derived cells, our previously described 3-dimensional intestinal organogenesis method was adapted to transwell differentiation. Intestinal cells were assessed by marker expression through immunocytochemical and mRNA expression analyses, monolayer integrity through Transepithelial Electrical Resistance (TEER measurements and molecule permeability, and functionality by taking advantage the well-characterized intestinal transport mechanisms. In most cases, marker expression for primary hInEpCs and iPSC-derived cells appeared to be as good as or better than Caco-2. Furthermore, transwell monolayers exhibited high TEER with low permeability. Primary hInEpCs showed molecule efflux indicative of P-glycoprotein transport. Primary hInEpCs and iPSC-derived cells also showed neonatal Fc receptor-dependent binding of immunoglobulin G variants. Primary hInEpCs and iPSC-derived intestinal cells exhibit expected marker expression and demonstrate basic functional monolayer formation, similar to or better than Caco-2. These cells could offer an alternative source of human intestinal cells for understanding normal intestinal epithelial physiology and drug transport.

  8. Lactic Acid Bacteria and the Human Intestinal Microbiome

    NARCIS (Netherlands)

    Douillard, F.P.; Vos, de W.M.

    2015-01-01

    The great interest in the human microbiome has revived attention paid to LAB presence in the human intestine. This chapter first discusses the LAB associated with the human intestinal microbiota and their potential roles in health and diseases. It then addresses recent metagenomic studies that chall

  9. 黏液填充在消化道上皮微缺损及肠屏障功能中的作用%Mucus fills the intestinal epithelial gaps and maintains the barrier function

    Institute of Scientific and Technical Information of China (English)

    周晓艳; 李铭; 郭婧; 左秀丽; 李延青

    2015-01-01

    Objective To investigate whether mucus fills the intestinal epithelial gaps(IEG),and to explore the role of mucus in maintaining local barrier function.Methods The terminal ileum tissues of ulcerative colitis (UC)patients and controls were obtained.Mucins were stained with Alcian Blue-Periodic Acid Schiff (AB-PAS)and Muc2.In addi-tion,we also analyzed the confocal laser endomicroscopy (CLE)imagines of the terminal ileum from 39 UC patients and 34 controls since January 2013 to December 2014.Revised Watson grading system was used to evaluate the local barrier function.Results In UC patients,the proportion [M(P25 ,P75 ),%]of IEG without mucus,intestinal epitheli-al gaps,goblet cells were 27.52(25.00,29.68),5.33(3.48,6.62)and 17.38(16.00,19.87),respectively.In con-trol group,these three parameters were 12.27(9.78,16.67),0.27(0.00,0.69)and 23.44(20.24,26.18),respec-tively.The differences were statistically significant in the two groups (P <0.01).The proportion of intestinal epithelial gaps and goblet cells showed a significantly negative correlation(r =-0.74,P <0.01).Conclusion The local barrier function is lost in UC patients;mucus filled with IEG play a key role to maintain the local intestinal barrier function.%目的:探讨黏液是否参与填充肠上皮单层细胞间的微缺损(intestinal epithelial gaps,IEG),评价黏液填充IEG 在局部肠屏障功能中的作用。方法取溃疡性结肠炎(UC)患者及对照组的回肠末端组织,用 AB-PAS、Muc2标记黏蛋白,观察 IEG 及黏蛋白表达情况。另外,分析了2013年1月至2014年12月39例 UC 患者及34例对照共聚焦内镜图片,运用改良 Watson 分级方法评估局部肠屏障功能。结果UC 组 IEG 未被黏液填充率、上皮微缺损率、杯状细胞比率[M(P25,P75),%]分别为27.52(25.00,29.68)、5.33(3.48,6.62)、17.38(16.00,19.87),对照组分别为12.27(9.78,16.67)、0.27(0.00,0.69

  10. Dynamic efficiency of the human intestinal microbiota.

    Science.gov (United States)

    Candela, Marco; Biagi, Elena; Turroni, Silvia; Maccaferri, Simone; Figini, Paolo; Brigidi, Patrizia

    2015-06-01

    The emerging dynamic dimensions of the human intestinal microbiota (IM) are challenging the traditional definition of healthy gut microbiota, principally based on the static concepts of phylogenetic and functional core. On the other hand, recent researches are revealing that the microbiota plasticity is strategic for several aspects of our biology, addressing the different immunological and metabolic needs at various ages, and adjusting the ecosystem services in response to different lifestyle, physiological states or diets. In light of these studies, we propose to revise the traditional concept of healthy human IM, including its degree of plasticity among the fundamental requisites for providing host health. In order to make a model taking into account the relative importance of IM core functions and plasticity for the maintenance of host health, we address to Economics, where the efficiency of a productive system is measured by computing static and dynamic parameters.

  11. Chronic mucus hypersecretion

    DEFF Research Database (Denmark)

    Harmsen, L; Thomsen, S F; Sylvan Ingebrigtsen, Truls;

    2010-01-01

    Chronic mucus hypersecretion (CMH) is a common condition in patients with chronic respiratory diseases. Little is known about the incidence, prevalence and determinants of CMH in younger individuals....

  12. Lactobacillus Adhesion to Mucus

    Directory of Open Access Journals (Sweden)

    Maxwell L. Van Tassell

    2011-05-01

    Full Text Available Mucus provides protective functions in the gastrointestinal tract and plays an important role in the adhesion of microorganisms to host surfaces. Mucin glycoproteins polymerize, forming a framework to which certain microbial populations can adhere, including probiotic Lactobacillus species. Numerous mechanisms for adhesion to mucus have been discovered in lactobacilli, including partially characterized mucus binding proteins. These mechanisms vary in importance with the in vitro models studied, which could significantly affect the perceived probiotic potential of the organisms. Understanding the nature of mucus-microbe interactions could be the key to elucidating the mechanisms of probiotic adhesion within the host.

  13. Generation of tissue-engineered small intestine using embryonic stem cell-derived human intestinal organoids.

    Science.gov (United States)

    Finkbeiner, Stacy R; Freeman, Jennifer J; Wieck, Minna M; El-Nachef, Wael; Altheim, Christopher H; Tsai, Yu-Hwai; Huang, Sha; Dyal, Rachel; White, Eric S; Grikscheit, Tracy C; Teitelbaum, Daniel H; Spence, Jason R

    2015-10-12

    Short bowel syndrome (SBS) is characterized by poor nutrient absorption due to a deficit of healthy intestine. Current treatment practices rely on providing supportive medical therapy with parenteral nutrition; while life saving, such interventions are not curative and are still associated with significant co-morbidities. As approaches to lengthen remaining intestinal tissue have been met with only limited success and intestinal transplants have poor survival outcomes, new approaches to treating SBS are necessary. Human intestine derived from embryonic stem cells (hESCs) or induced pluripotent stem cells (iPSCs), called human intestinal organoids (HIOs), have the potential to offer a personalized and scalable source of intestine for regenerative therapies. However, given that HIOs are small three-dimensional structures grown in vitro, methods to generate usable HIO-derived constructs are needed. We investigated the ability of hESCs or HIOs to populate acellular porcine intestinal matrices and artificial polyglycolic/poly L lactic acid (PGA/PLLA) scaffolds, and examined the ability of matrix/scaffolds to thrive when transplanted in vivo. Our results demonstrate that the acellular matrix alone is not sufficient to instruct hESC differentiation towards an endodermal or intestinal fate. We observed that while HIOs reseed acellular porcine matrices in vitro, the HIO-reseeded matrices do not thrive when transplanted in vivo. In contrast, HIO-seeded PGA/PLLA scaffolds thrive in vivo and develop into tissue that looks nearly identical to adult human intestinal tissue. Our results suggest that HIO-seeded PGA/PLLA scaffolds are a promising avenue for developing the mucosal component of tissue engineered human small intestine, which need to be explored further to develop them into fully functional tissue.

  14. Generation of tissue-engineered small intestine using embryonic stem cell-derived human intestinal organoids

    Directory of Open Access Journals (Sweden)

    Stacy R. Finkbeiner

    2015-11-01

    Full Text Available Short bowel syndrome (SBS is characterized by poor nutrient absorption due to a deficit of healthy intestine. Current treatment practices rely on providing supportive medical therapy with parenteral nutrition; while life saving, such interventions are not curative and are still associated with significant co-morbidities. As approaches to lengthen remaining intestinal tissue have been met with only limited success and intestinal transplants have poor survival outcomes, new approaches to treating SBS are necessary. Human intestine derived from embryonic stem cells (hESCs or induced pluripotent stem cells (iPSCs, called human intestinal organoids (HIOs, have the potential to offer a personalized and scalable source of intestine for regenerative therapies. However, given that HIOs are small three-dimensional structures grown in vitro, methods to generate usable HIO-derived constructs are needed. We investigated the ability of hESCs or HIOs to populate acellular porcine intestinal matrices and artificial polyglycolic/poly L lactic acid (PGA/PLLA scaffolds, and examined the ability of matrix/scaffolds to thrive when transplanted in vivo. Our results demonstrate that the acellular matrix alone is not sufficient to instruct hESC differentiation towards an endodermal or intestinal fate. We observed that while HIOs reseed acellular porcine matrices in vitro, the HIO-reseeded matrices do not thrive when transplanted in vivo. In contrast, HIO-seeded PGA/PLLA scaffolds thrive in vivo and develop into tissue that looks nearly identical to adult human intestinal tissue. Our results suggest that HIO-seeded PGA/PLLA scaffolds are a promising avenue for developing the mucosal component of tissue engineered human small intestine, which need to be explored further to develop them into fully functional tissue.

  15. Receptor-like Molecules on Human Intestinal Epithelial Cells Interact with an Adhesion Factor from Lactobacillus reuteri.

    Science.gov (United States)

    Matsuo, Yosuke; Miyoshi, Yukihiro; Okada, Sanae; Satoh, Eiichi

    2012-01-01

    A surface protein of Lactobacillus reuteri, mucus adhesion-promoting protein (MapA), is considered to be an adhesion factor. MapA is expressed in L. reuteri strains and adheres to piglet gastric mucus, collagen type I, and human intestinal epithelial cells such as Caco-2. The aim of this study was to identify molecules that mediate the attachment of MapA from L. reuteri to the intestinal epithelial cell surface by investigating the adhesion of MapA to receptor-like molecules on Caco-2 cells. MapA-binding receptor-like molecules were detected in Caco-2 cell lysates by 2D-PAGE. Two proteins, annexin A13 (ANXA13) and paralemmin (PALM), were identified by MALDI TOF-MS. The results of a pull-down assay showed that MapA bound directly to ANXA13 and PALM. Fluorescence microscopy studies confirmed that MapA binding to ANXA13 and PALM was colocalized on the Caco-2 cell membrane. To evaluate whether ANXA13 and PALM are important for MapA adhesion, ANXA13 and PALM knockdown cell lines were established. The adhesion of MapA to the abovementioned cell lines was reduced compared with that to wild-type Caco-2 cells. These knockdown experiments established the importance of these receptor-like molecules in MapA adhesion.

  16. A Revised Model for Dosimetry in the Human Small Intestine

    Energy Technology Data Exchange (ETDEWEB)

    John Poston; Nasir U. Bhuiyan; R. Alex Redd; Neil Parham; Jennifer Watson

    2005-02-28

    A new model for an adult human gastrointestinal tract (GIT) has been developed for use in internal dose estimations to the wall of the GIT and to the other organs and tissues of the body from radionuclides deposited in the lumenal contents of the five sections of the GIT. These sections were the esophasgus, stomach, small intestine, upper large intestine, and the lower large intestine. The wall of each section was separated from its lumenal contents.

  17. Techniques to Bring Up Mucus

    Science.gov (United States)

    ... COPD: Lifestyle Management Techniques to Bring Up Mucus Techniques to Bring Up Mucus Make an Appointment Refer ... breathing may become difficult, and infection may occur. Techniques to remove mucus are often done after using ...

  18. Exploring food effects on indinavir absorption with human intestinal fluids in the mouse intestine.

    Science.gov (United States)

    Holmstock, Nico; De Bruyn, Tom; Bevernage, Jan; Annaert, Pieter; Mols, Raf; Tack, Jan; Augustijns, Patrick

    2013-04-11

    Food can have a significant impact on the pharmacokinetics of orally administered drugs, as it may affect drug solubility as well as permeability. Since fed state conditions cannot easily be implemented in the presently available permeability tools, including the frequently used Caco-2 system, exploring food effects during drug development can be quite challenging. In this study, we investigated the effect of fasted and fed state conditions on the intestinal absorption of the HIV protease inhibitor indinavir using simulated and human intestinal fluids in the in situ intestinal perfusion technique in mice. Although the solubility of indinavir was 6-fold higher in fed state human intestinal fluids (FeHIF) as compared to fasted state HIF (FaHIF), the intestinal permeation of indinavir was 22-fold lower in FeHIF as compared to FaHIF. Dialysis experiments showed that only a small fraction of indinavir is accessible for absorption in FeHIF due to micellar entrapment, possibly explaining its low intestinal permeation. The presence of ritonavir, a known P-gp inhibitor, increased the intestinal permeation of indinavir by 2-fold in FaHIF, while there was no increase when using FeHIF. These data confirm that drug-food interactions form a complex interplay between solubility and permeability effects. The use of HIF in in situ intestinal perfusions holds great promise for biorelevant absorption evaluation as it allows to directly explore this complex solubility/permeability interplay on drug absorption.

  19. The gastrointestinal mucus system in health and disease.

    Science.gov (United States)

    Johansson, Malin E V; Sjövall, Henrik; Hansson, Gunnar C

    2013-06-01

    Mucins--large, highly glycosylated proteins--are important for the luminal protection of the gastrointestinal tract. Enterocytes have their apical surface covered by transmembrane mucins and goblet cells produce the secreted gel-forming mucins that form mucus. The small intestine has a single unattached mucus layer, which in cystic fibrosis becomes attached, accounting for the intestinal manifestations of this disease. The stomach and colon have two layers of mucus; the inner layer is attached and the outer layer is less dense and unattached. In the colon, the outer mucus layer is the habitat for commensal bacteria. The inner mucus layer is impervious to bacteria and is renewed every hour by surface goblet cells. The crypt goblet cells have the ability to restitute the mucus layer by secretion, for example after an ischaemic challenge. Proteases of certain parasites and some bacteria can cleave mucins and dissolve the mucus as part of their pathogenicity. The inner mucus layer can, however, also become penetrable to bacteria by several other mechanisms, including aberrations in the immune system. When bacteria reach the epithelial surface, the immune system is activated and inflammation is triggered. This mechanism might occur in some types of ulcerative colitis.

  20. Active microrheology of Chaetopterus mucus determines three intrinsic lengthscales that govern material properties

    CERN Document Server

    Weigand, W J; Deheyn, D D; Morales-Sanz, A; Blair, D L; Urbach, J S; Robertson-Anderson, R M

    2016-01-01

    We characterize the scale-dependent rheological properties of mucus from the Chaetopterus marine worm and determine the intrinsic lengthscales controlling distinct rheological and structural regimes. Mucus produced by this ubiquitous filter feeder serves a host of roles including filtration, protection and trapping nutrients. The ease of clean mucus extraction coupled with similarities to human mucus rheology also make Chaetopterus mucus a potential model system for elucidating human mucus mechanics. We use optically trapped microsphere probes of 2-10 microns, to induce oscillatory strains and measure mucus stress response. We show that viscoelastic properties are highly dependent on the strain scale (l) with three distinct regimes emerging: microscale: l_110 microns. While mucus response is similar to water for l_1 indicating that probes rarely contact the mucus mesh, for l_2 the response is distinctly more viscous and independent of probe size, demonstrating that the mucus behaves as a continuum. However, t...

  1. Intestinal Colonization Dynamics of Vibrio cholerae

    Science.gov (United States)

    Almagro-Moreno, Salvador; Pruss, Kali; Taylor, Ronald K.

    2015-01-01

    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. PMID:25996593

  2. Intestinal and hepatic metabolism of glutamine and citrulline in humans.

    Science.gov (United States)

    van de Poll, Marcel C G; Ligthart-Melis, Gerdien C; Boelens, Petra G; Deutz, Nicolaas E P; van Leeuwen, Paul A M; Dejong, Cornelis H C

    2007-06-01

    Glutamine plays an important role in nitrogen homeostasis and intestinal substrate supply. It has been suggested that glutamine is a precursor for arginine through an intestinal-renal pathway involving inter-organ transport of citrulline. The importance of intestinal glutamine metabolism for endogenous arginine synthesis in humans, however, has remained unaddressed. The aim of this study was to investigate the intestinal conversion of glutamine to citrulline and the effect of the liver on splanchnic citrulline metabolism in humans. Eight patients undergoing upper gastrointestinal surgery received a primed continuous intravenous infusion of [2-(15)N]glutamine and [ureido-(13)C-(2)H(2)]citrulline. Arterial, portal venous and hepatic venous blood were sampled and portal and hepatic blood flows were measured. Organ specific amino acid uptake (disposal), production and net balance, as well as whole body rates of plasma appearance were calculated according to established methods. The intestines consumed glutamine at a rate that was dependent on glutamine supply. Approximately 13% of glutamine taken up by the intestines was converted to citrulline. Quantitatively glutamine was the only important precursor for intestinal citrulline release. Both glutamine and citrulline were consumed and produced by the liver, but net hepatic flux of both amino acids was not significantly different from zero. Plasma glutamine was the precursor of 80% of plasma citrulline and plasma citrulline in turn was the precursor of 10% of plasma arginine. In conclusion, glutamine is an important precursor for the synthesis of arginine after intestinal conversion to citrulline in humans.

  3. A simple method for measuring thickness of the mucus gel layer adherent to rat, frog and human gastric mucosa: influence of feeding, prostaglandin, N-acetylcysteine and other agents.

    Science.gov (United States)

    Kerss, S; Allen, A; Garner, A

    1982-08-01

    1. A technique has been developed for measuring thickness of the gastric surface mucus gel layer. Mucosal sections (1.6 mm) were cut from frog and rat stomach and human antrum, mounted transversely and viewed by an inverse microscope (x 200 magnification) under dark field illumination or phase contrast. The mucus layer was readily distinguishable and its dimensions could be recorded by means of an eyepiece graticule. 2. Mean mucus gel thickness in rat, frog was 73, 76, 55 and 192 micrometer respectively. However, there was variation in the average thickness of the gel layer between individual mucosae from the same species (up to twofold). Mucus thickness between adjacent regions of the same mucosal section also varied markedly (up to tenfold). 3. Topical administration of 16,16-dimethylprostaglandin E2 by oral intubation caused a significant increase in thickness in both rat and frog at doses of 5 microgram/ml and 0.5 microgram/ml respectively. Feeding and exposure of the mucosa to N-acetylcysteine (10-20%, w/v) produced variable effects whereas pepsin (1 mg/ml) caused a marked reduction in thickness of the surface gel layer in both rat and frog. 4. The technique provides a rapid and simple method for determining gastrointestinal mucus thickness in relation to mucosal morphology. It is ideally suited for studying the control of mucus secretion and effect of drugs.

  4. Human intestinal microbiota and type 1 diabetes.

    Science.gov (United States)

    Vaarala, Outi

    2013-10-01

    The role of intestinal microbiota in immune-mediated diseases, such as type 1 diabetes, has deservedly received a lot of attention. Evidently, changes in the intestinal microbiota are associated with type 1 diabetes as demonstrated by recent studies. Children with beta-cell autoimmunity have shown low abundance of butyrate-producing bacteria and increase in the abundance of members of the Bacteroidetes phylum in fecal microbiota. These alterations could explain increased gut permeability, subclinical small intestinal inflammation, and dysregulation of oral tolerance in type 1 diabetes. However, these studies do not provide evidence of the causative role of the gut microbiota in the development of beta-cell autoimmunity, yet. In animal models, the composition of gut microbiota modulates the function of both innate and adaptive immunity, and intestinal bacteria are regulators of autoimmune diabetes. Thus, prevention of type 1 diabetes could, in the future, be based on the interventions targeted to the gut microbiota.

  5. Corneal mucus plaques.

    Science.gov (United States)

    Fraunfelder, F T; Wright, P; Tripathi, R C

    1977-02-01

    Corneal mucus plaques adhered to the anterior corneal surface in 17 of 67 advanced cases of keratoconjunctivitis sicca. The plaques were translucent to opaque and varied in size and shape, from multiple isolated islands to bizarre patterns involving more than half the corneal surface. Ultrastructurally, they consisted of mucus mixed with desquamated degenerating epithelial cells and proteinaceous and lipoidal material. The condition may be symptomatic but can be controlled and prevented in most cases by topical ocular application of 10% acetylcysteine.

  6. Distinct human stem cell populations in small and large intestine.

    Science.gov (United States)

    Cramer, Julie M; Thompson, Timothy; Geskin, Albert; LaFramboise, William; Lagasse, Eric

    2015-01-01

    The intestine is composed of an epithelial layer containing rapidly proliferating cells that mature into two regions, the small and the large intestine. Although previous studies have identified stem cells as the cell-of-origin for intestinal epithelial cells, no studies have directly compared stem cells derived from these anatomically distinct regions. Here, we examine intrinsic differences between primary epithelial cells isolated from human fetal small and large intestine, after in vitro expansion, using the Wnt agonist R-spondin 2. We utilized flow cytometry, fluorescence-activated cell sorting, gene expression analysis and a three-dimensional in vitro differentiation assay to characterize their stem cell properties. We identified stem cell markers that separate subpopulations of colony-forming cells in the small and large intestine and revealed important differences in differentiation, proliferation and disease pathways using gene expression analysis. Single cells from small and large intestine cultures formed organoids that reflect the distinct cellular hierarchy found in vivo and respond differently to identical exogenous cues. Our characterization identified numerous differences between small and large intestine epithelial stem cells suggesting possible connections to intestinal disease.

  7. Distinct human stem cell populations in small and large intestine.

    Directory of Open Access Journals (Sweden)

    Julie M Cramer

    Full Text Available The intestine is composed of an epithelial layer containing rapidly proliferating cells that mature into two regions, the small and the large intestine. Although previous studies have identified stem cells as the cell-of-origin for intestinal epithelial cells, no studies have directly compared stem cells derived from these anatomically distinct regions. Here, we examine intrinsic differences between primary epithelial cells isolated from human fetal small and large intestine, after in vitro expansion, using the Wnt agonist R-spondin 2. We utilized flow cytometry, fluorescence-activated cell sorting, gene expression analysis and a three-dimensional in vitro differentiation assay to characterize their stem cell properties. We identified stem cell markers that separate subpopulations of colony-forming cells in the small and large intestine and revealed important differences in differentiation, proliferation and disease pathways using gene expression analysis. Single cells from small and large intestine cultures formed organoids that reflect the distinct cellular hierarchy found in vivo and respond differently to identical exogenous cues. Our characterization identified numerous differences between small and large intestine epithelial stem cells suggesting possible connections to intestinal disease.

  8. Immunomodulatory Properties of Streptococcus and Veillonella Isolates from the Human Small Intestine Microbiota

    NARCIS (Netherlands)

    Bogert, van den B.; Meijerink, M.; Zoetendal, E.G.; Wells, J.M.; Kleerebezem, M.

    2014-01-01

    The human small intestine is a key site for interactions between the intestinal microbiota and the mucosal immune system. Here we investigated the immunomodulatory properties of representative species of commonly dominant small-intestinal microbial communities, including six streptococcal strains

  9. Detection of mucus glycoconjugates in human conjunctiva by using the lectin colloidal gold technique in TEM. I. A quantitative study in normal subjects.

    Science.gov (United States)

    Versura, P; Maltarello, M C; Bonvicini, F; Caramazza, R; Laschi, R

    1986-08-01

    We applied a specific cytochemical reaction to characterize the glycoconjugates produced by goblet and non-goblet epithelial cells of normal human conjunctiva. For this purpose we utilized the lectins, proteins of vegetal origin, which are extremely sensitive in binding glycosidic residues. In particular, we used WGA, PNA, SBA and ConA conjugated with colloidal gold as ultrastructural marker for Transmission Electron Microscopy. This technique allowed us also to perform a quantitative analysis, by counting colloidal gold particles present on mucus granules. In this way we analyzed the content both of goblet and non-goblet epithelial cells. In the former, WGA, PNA, SBA and ConA receptors, here reported in decreasing density, were present. In the latter WGA was always positive, SBA and PNA sometimes were negative, ConA was always negative. We speculate the different contribution to mucus production by these two sources may be important in evaluating tear film stability alterations occurring in those diseases in which non-goblet epithelial cell vesicles increase.

  10. Understanding drug resistance in human intestinal protozoa.

    Science.gov (United States)

    El-Taweel, Hend Aly

    2015-05-01

    Infections with intestinal protozoa continue to be a major health problem in many areas of the world. The widespread use of a limited number of therapeutic agents for their management and control raises concerns about development of drug resistance. Generally, the use of any antimicrobial agent should be accompanied by meticulous monitoring of its efficacy and measures to minimize resistance formation. Evidence for the occurrence of drug resistance in different intestinal protozoa comes from case studies and clinical trials, sometimes with a limited number of patients. Large-scale field-based assessment of drug resistance and drug sensitivity testing of clinical isolates are needed. Furthermore, the association of drug resistance with certain geographic isolates or genotypes deserves consideration. Drug resistance has been triggered in vitro and has been linked to modification of pyruvate:ferredoxin oxidoreductase, nitroreductases, antioxidant defense, or cytoskeletal system. Further mechanistic studies will have important implications in the development of second generation therapeutic agents.

  11. Intestine.

    Science.gov (United States)

    Smith, J M; Skeans, M A; Horslen, S P; Edwards, E B; Harper, A M; Snyder, J J; Israni, A K; Kasiske, B L

    2016-01-01

    Intestine and intestine-liver transplant plays an important role in the treatment of intestinal failure, despite decreased morbidity associated with parenteral nutrition. In 2014, 210 new patients were added to the intestine transplant waiting list. Among prevalent patients on the list at the end of 2014, 65% were waiting for an intestine transplant and 35% were waiting for an intestine-liver transplant. The pretransplant mortality rate decreased dramatically over time for all age groups. Pretransplant mortality was highest for adult candidates, at 22.1 per 100 waitlist years compared with less than 3 per 100 waitlist years for pediatric candidates, and notably higher for candidates for intestine-liver transplant than for candidates for intestine transplant without a liver. Numbers of intestine transplants without a liver increased from a low of 51 in 2013 to 67 in 2014. Intestine-liver transplants increased from a low of 44 in 2012 to 72 in 2014. Short-gut syndrome (congenital and other) was the main cause of disease leading to both intestine and intestine-liver transplant. Graft survival improved over the past decade. Patient survival was lowest for adult intestine-liver recipients and highest for pediatric intestine recipients.

  12. Campylobacter-induced interleukin-8 responses in human intestinal epithelial cells and primary intestinal chick cells.

    Science.gov (United States)

    Borrmann, Erika; Berndt, Angela; Hänel, Ingrid; Köhler, Heike

    2007-09-20

    Campylobacter (C.) jejuni and C. coli can cause gastrointestinal disorders in humans characterized by acute inflammation. Inflammatory signals are initiated during interaction between these pathogens and human intestinal cells, but nothing is known about the stimulation of avian intestinal cells by Campylobacter. Interleukin-8 (IL-8) as a proinflammatory chemokine plays an important role in mobilizing cellular defence mechanism. IL-8 mRNA expression in both human intestinal cells (INT 407) and primary intestinal chick cells (PIC) was determined by quantitative real-time RT-PCR. The secretion of IL-8 protein by INT407 was measured using ELISA. Although C. jejuni and C. coli are considered to be harmless commensals in the gut of birds, the avian Campylobacter isolates investigated were able to induce the proinflammatory IL-8 in PIC as well as in INT407. In an in vitro system, C. jejuni as well as C. coli were able to induce IL-8 mRNA in PIC. Relation between the virulence properties like toxin production, the ability to invade and to survive in Caco-2 cells and the level of IL-8 mRNA produced by INT 407 and PIC after infection with Campylobacter strains was also investigated.

  13. Bacteroides in the infant gut consume milk oligosaccharides via mucus-utilization pathways.

    Science.gov (United States)

    Marcobal, Angela; Barboza, Mariana; Sonnenburg, Erica D; Pudlo, Nicholas; Martens, Eric C; Desai, Prerak; Lebrilla, Carlito B; Weimer, Bart C; Mills, David A; German, J Bruce; Sonnenburg, Justin L

    2011-11-17

    Newborns are colonized with an intestinal microbiota shortly after birth, but the factors governing the retention and abundance of specific microbial lineages are unknown. Nursing infants consume human milk oligosaccharides (HMOs) that pass undigested to the distal gut, where they may be digested by microbes. We determined that the prominent neonate gut residents, Bacteroides thetaiotaomicron and Bacteroides fragilis, induce the same genes during HMO consumption that are used to harvest host mucus glycans, which are structurally similar to HMOs. Lacto-N-neotetraose, a specific HMO component, selects for HMO-adapted species such as Bifidobacterium infantis, which cannot use mucus, and provides a selective advantage to B. infantis in vivo when biassociated with B. thetaiotaomicron in the gnotobiotic mouse gut. This indicates that the complex oligosaccharide mixture within HMOs attracts both mutualistic mucus-adapted species and HMO-adapted bifidobacteria to the infant intestine that likely facilitate both milk and future solid food digestion. Copyright © 2011 Elsevier Inc. All rights reserved.

  14. The Interaction of Large Bowel Microflora with the Colonic Mucus Barrier

    Directory of Open Access Journals (Sweden)

    Jeffrey P. Pearson

    2010-01-01

    Full Text Available The colonic mucus barrier is the first line of defence that the underlying mucosa has against the wide range of potentially damaging agents of microbial, endogenous, and dietary origin that occur within the colonic lumen. The functional component of mucus is the secreted, polymeric glycoprotein mucin. The mucus barrier can either act as an energy source or a support medium for growth to the intestinal microflora. The mucus barrier appears to effectively partition the vast number of microbial cells from the underlying epithelium. The normal functionality and biochemistry of this mucus barrier appears to be lost in diseases of the colorectal mucosa. Germ-free animal studies have highlighted the necessity of the presence of the colonic microflora to drive the maturation of the colonic mucosa and normal mucus production. A number of by-products of the microflora have been suggested to be key luminal drivers of colonic mucus secretion.

  15. Effect of heat stress on intestinal barrier function of human intestinal epithelial Caco-2 cells

    Directory of Open Access Journals (Sweden)

    Gui-zhen XIAO

    2013-07-01

    Full Text Available Objective To investigate the heat stress-induced dysfunction of intestinal barrier including intestinal tight junction and apoptosis of epithelial cells. Methods Human intestinal epithelial Caco-2 cell monolayers, serving as the intestinal barrier model, were exposed to different temperature (37-43℃ for designated time. Transepithelial electrical resistance (TEER and horseradish peroxidase (HRP flux permeability were measured to evaluate barrier integrity. Level of tight junction (TJ protein occludin was analyzed by Western blotting. Cell apoptosis rate was determined using Annexin V-FITC/PI kit by flow cytometry. Results Compared with the 37℃ group, TEER lowered and the permeability for HRP increased significantly after heat exposure (P<0.01 in 39℃, 41℃ and 43℃ groups. The expression of occludin increased when the temperature was elevated from 37℃ to 41℃, and it reached the maximal level at 41℃. However, its expression gradually decreased with passage of time at 43℃. Cell apoptosis was enhanced with elevation of the temperature (P<0.05 or P<0.01. Conclusion Heat stress can induce damage to tight junction and enhance apoptosis of epithelial cells, thus causing dysfunction of intestinal epithelial barrier.

  16. IL-13–induced airway mucus production is attenuated by MAPK13 inhibition

    Science.gov (United States)

    Alevy, Yael G.; Patel, Anand C.; Romero, Arthur G.; Patel, Dhara A.; Tucker, Jennifer; Roswit, William T.; Miller, Chantel A.; Heier, Richard F.; Byers, Derek E.; Brett, Tom J.; Holtzman, Michael J.

    2012-01-01

    Increased mucus production is a common cause of morbidity and mortality in inflammatory airway diseases, including asthma, chronic obstructive pulmonary disease (COPD), and cystic fibrosis. However, the precise molecular mechanisms for pathogenic mucus production are largely undetermined. Accordingly, there are no specific and effective anti-mucus therapeutics. Here, we define a signaling pathway from chloride channel calcium-activated 1 (CLCA1) to MAPK13 that is responsible for IL-13–driven mucus production in human airway epithelial cells. The same pathway was also highly activated in the lungs of humans with excess mucus production due to COPD. We further validated the pathway by using structure-based drug design to develop a series of novel MAPK13 inhibitors with nanomolar potency that effectively reduced mucus production in human airway epithelial cells. These results uncover and validate a new pathway for regulating mucus production as well as a corresponding therapeutic approach to mucus overproduction in inflammatory airway diseases. PMID:23187130

  17. Application of the Human Intestinal Tract Chip to the non-human primate gut microbiota

    NARCIS (Netherlands)

    Bello Gonzalez, T.D.G.; Passel, van M.W.J.; Tims, S.; Fuentes, S.; Vos, de W.M.; Smidt, H.; Belzer, C.

    2015-01-01

    The human intestinal microbiota is responsible for various health-related functions, and its diversity can be readily mapped with the 16S ribosomal RNA targeting Human Intestinal Tract (HIT) Chip. Here we characterise distal gut samples from chimpanzees, gorillas and marmosets, and compare them with

  18. Application of the Human Intestinal Tract Chip to the non-human primate gut microbiota

    NARCIS (Netherlands)

    Bello Gonzalez, T.D.G.; Passel, van M.W.J.; Tims, S.; Fuentes, S.; Vos, de W.M.; Smidt, H.; Belzer, C.

    2015-01-01

    The human intestinal microbiota is responsible for various health-related functions, and its diversity can be readily mapped with the 16S ribosomal RNA targeting Human Intestinal Tract (HIT) Chip. Here we characterise distal gut samples from chimpanzees, gorillas and marmosets, and compare them with

  19. Mucus hypersecretion in the airway

    Institute of Scientific and Technical Information of China (English)

    WANG Ke; WEN Fu-qiang; XU Dan

    2008-01-01

    @@ Mucus hypersecretion is a distinguishing feature of Chronic intlammation diseases,such as asthma,1chronic bronchitis.2 bronchiectasis3 and cystic fibrosis.4Mucus hypersecretion leads to impairment of mucociliary clearance,abnormal bacterial plantation,mucus plug in the airway,and dysfunction of gas exchange.5

  20. Physiotherapy and bronchial mucus transport

    NARCIS (Netherlands)

    van der Schans, CP; Postma, DS; Koeter, GH; Rubin, BK

    Cough and expectoration of mucus are the best-known symptoms in patients with pulmonary disease, The most applied intervention for these symptoms is the use of chest physiotherapy to increase bronchial mucus transport and reduce retention of mucus in the airways, Chest physiotherapy interventions

  1. Physiotherapy and bronchial mucus transport

    NARCIS (Netherlands)

    van der Schans, CP; Postma, DS; Koeter, GH; Rubin, BK

    1999-01-01

    Cough and expectoration of mucus are the best-known symptoms in patients with pulmonary disease, The most applied intervention for these symptoms is the use of chest physiotherapy to increase bronchial mucus transport and reduce retention of mucus in the airways, Chest physiotherapy interventions ca

  2. Functional characterization of cholera toxin inhibitors using human intestinal organoids

    NARCIS (Netherlands)

    Zomer-van Ommen, Domenique D.; Pukin, Aliaksei V.; Fu, Ou; Quarles Van Ufford, Linda H C; Janssens, Hettie M.; Beekman, Jeffrey M.; Pieters, Roland J.

    2016-01-01

    Preclinical drug testing in primary human cell models that recapitulate disease can significantly reduce animal experimentation and time-to-the-clinic. We used intestinal organoids to quantitatively study the potency of multivalent cholera toxin inhibitors. The method enabled the determination of IC

  3. In silico modelling of the human intestinal microflora

    NARCIS (Netherlands)

    Kamerman, DJ; Wilkinson, MHF; Sloot, P; Tan, CJK; Dongarra, JJ; Hoekstra, AG

    2002-01-01

    The ecology of the human intestinal microflora and its interaction with the host are poorly understood. Though more and more data are being acquired, in part using modern molecular methods, development of a quantitative theory has not kept pace with this development. This is in part due to the compl

  4. In Silico Modelling of the Human Intestinal Microflora

    NARCIS (Netherlands)

    Kamerman, Derk Jan; Wilkinson, Michael H.F.

    2002-01-01

    The ecology of the human intestinal microflora and its interaction with the host are poorly understood. Though more and more data are being acquired, in part using modern molecular methods, development of a quantitative theory has not kept pace with this development. This is in part due to the compl

  5. Dietary protein absorption of the small intestine in human neonates

    NARCIS (Netherlands)

    Schaart, Maaike W.; de Bruijn, Adrianus C. J. M.; Tibboel, Dick; Renes, Ingrid B.; van Goudoever, Johannes B.

    2007-01-01

    Background: The intestine plays a key role in the absorption of dietary proteins, which determines growth of human neonates. Bowel resection in the neonatal period brings loss of absorptive and protective surface and may consequently lead to malabsorption of dietary nutrients. However, there are no

  6. Functional characterization of cholera toxin inhibitors using human intestinal organoids

    NARCIS (Netherlands)

    Zomer-van Ommen, Domenique D.; Pukin, Aliaksei V.; Fu, Ou; Quarles Van Ufford, Linda H C; Janssens, Hettie M.; Beekman, Jeffrey M.; Pieters, Roland J.

    2016-01-01

    Preclinical drug testing in primary human cell models that recapitulate disease can significantly reduce animal experimentation and time-to-the-clinic. We used intestinal organoids to quantitatively study the potency of multivalent cholera toxin inhibitors. The method enabled the determination of

  7. Methane and hydrogen production by human intestinal anaerobic bacteria.

    Science.gov (United States)

    McKay, L F; Holbrook, W P; Eastwood, M A

    1982-06-01

    The gas above liquid cultures of a variety of human intestinal anaerobic bacteria was sampled and analysed by headspace gas chromatography. Hydrogen production was greatest with strains of the genus Clostridium, intermediate with anaerobic cocci and least with Bacteroides sp. Very few strains produced methane although small amounts were detected with one strain of B. thetaiotaomicron, C. perfringens and C. histolyticum. There may be a relationship between these anaerobic bacteria and several gastrointestinal disorders in which there is a build up of hydrogen or methane in the intestines.

  8. Molecular epidemiology of human intestinal amoebas in iran.

    Science.gov (United States)

    Hooshyar, H; Rostamkhani, P; Rezaian, M

    2012-01-01

    Many microscopic-based epidemiological surveys on the prevalence of human intestinal pathogenic and non-pathogenic protozoa including intestinal amoeba performed in Iran show a high prevalence of human intestinal amoeba in different parts of Iran. Such epidemiological studies on amoebiasis are confusing, mainly due to recently appreciated distinction between the Entamoeba histolytica, E. dispar and E. moshkovskii. Differential diagnosis can be done by some methods such as PCR-based methods, monoclonal antibodies and the analysis of isoenzyme typing, however the molecular study of these protozoa in Iran is low. Based on molecular studies, it seems that E. dispar is predominant species especially in the central and northern areas of Iran and amoebiasis due to E. histolytica is a rare infection in the country. It is suggested that infection with E. moshkovskii may be common among Iranians. Considering the importance of molecular epidemiology of amoeba in Iran and also the current data, the present study reviews the data currently available on the molecular distribution of intestinal human amoeba in Iran.

  9. Molecular Epidemiology of Human Intestinal Amoebas in Iran

    Directory of Open Access Journals (Sweden)

    M Rezaian

    2012-09-01

    Full Text Available Many microscopic-based epidemiological surveys on the prevalence of human intestinal pathogenic and non-pathogenic protozoa including intestinal amoeba performed in Iran show a high prevalence of human intestinal amoeba in different parts of Iran. Such epidemiological studies on amoebiasis are confusing, mainly due to recently appreciated distinction between the Entamoeba histolytica, E. dispar and E. moshkovskii. Differential diagnosis can be done by some methods such as PCR-based methods, monoclonal antibodies and the analysis of isoenzyme typing, however the molecular study of these protozoa in Iran is low. Based on molecular studies, it seems that E. dispar is predominant species especially in the central and northern areas of Iran and amoebiasis due to E. histolytica is a rare infection in the country. It is suggested that infection with E. moshkovskii may be common among Iranians. Considering the importance of molecular epidemiology of amoeba in Iran and also the current data, the present study reviews the data currently available on the molecular distribution of intestinal human amoeba in Iran.

  10. Impact of diet on human intestinal microbiota and health.

    Science.gov (United States)

    Salonen, Anne; de Vos, Willem M

    2014-01-01

    Our intestinal microbiota is involved in the breakdown and bioconversion of dietary and host components that are not degraded and taken up by our own digestive system. The end products generated by our microbiota fuel our enterocytes and support growth but also have signaling functions that generate systemic immune and metabolic responses. Due to the immense metabolic capacity of the intestinal microbiota and its relatively high plasticity, there is great interest in identifying dietary approaches that allow intentional and predictable modulation of the microbiota. In this article, we review the current insights on dietary influence on the human intestinal microbiota based on recent high-throughput molecular studies and interconnections with health. We focus especially on the emerging data that identify the amount and type of dietary fat as significant modulators of the colonic microbiota and its metabolic output.

  11. Functional Metagenomic Investigations of the Human Intestinal Microbiota

    DEFF Research Database (Denmark)

    Moore, Aimee M.; Munck, Christian; Sommer, Morten Otto Alexander

    2011-01-01

    The human intestinal microbiota encode multiple critical functions impacting human health, including metabolism of dietary substrate, prevention of pathogen invasion, immune system modulation, and provision of a reservoir of antibiotic resistance genes accessible to pathogens. The complexity...... microorganisms, but relatively recently applied to the study of the human commensal microbiota. Metagenomic functional screens characterize the functional capacity of a microbial community, independent of identity to known genes, by subjecting the metagenome to functional assays in a genetically tractable host....... Here we highlight recent work applying this technique to study the functional diversity of the intestinal microbiota, and discuss how an approach combining high-throughput sequencing, cultivation, and metagenomic functional screens can improve our understanding of interactions between this complex...

  12. Infant intestinal Enterococcus faecalis down-regulates inflammatory responses in human intestinal cell lines

    Institute of Scientific and Technical Information of China (English)

    Shugui Wang; Lydia Hui Mei Ng; Wai Ling Chow; Yuan Kun Lee

    2008-01-01

    AIM:To investigate the ability of Lactic acid bacteria (LAB)to modulate inflammatory reaction in human intestinal celllines(Caco-2,HT-29 and HCT 116).Different strains of LAB isolatedfrom new born infants and fermented milk,together withthestrains obtained from culture collectionsweretested.METHODS:LABs were treated with human intestinal cell lines.ELISA was used to detect IL-8 and TGF-β protein secretion.Cytokines and Toll like receptors (TLRs) gene expression were assessed using RT-PCR.Conditional medium,sonicated bacteria and UV killed bacteria were used to find the effecter molecules on the bacteria.Carbohydrate oxidation and protein digestion were applied to figure out the molecules'residues.Adhesion assays were further carried out.RESULTS:It was found that Enterococcus faecalis is the main immune modulator among the LABs by downregulation of IL-8 secretion and upregulation of TGF-β.Strikingly,the effect was only observed in four strains of E.faecalis out of the 27 isolated and tested.This implies strain dependent immunomodulation in the host.In addition,E.faecalis may regulate inflammatory responses through TLR3,TLR4,TLR9 and TRAF6.Carbohydrates on the bacterial cell surface are involved in both its adhesion to intestinal cells and regulation of inflammatory responses in the host.CONCLUSION:These data provide a case for the modulation of intestinal mucosal immunity in which specific strains of E.faecalis have uniquely evolved to maintain colonic homeostasis and regulate inflammatoryresponses.

  13. DNA Supercoiling Regulates the Motility of Campylobacter jejuni and Is Altered by Growth in the Presence of Chicken Mucus.

    Science.gov (United States)

    Shortt, Claire; Scanlan, Eoin; Hilliard, Amber; Cotroneo, Chiara E; Bourke, Billy; Ó Cróinín, Tadhg

    2016-09-13

    Campylobacter jejuni is the leading cause of bacterial gastroenteritis in humans, but relatively little is known about the global regulation of virulence factors during infection of chickens or humans. This study identified DNA supercoiling as playing a key role in regulating motility and flagellar protein production and found that this supercoiling-controlled regulon is induced by growth in chicken mucus. A direct correlation was observed between motility and resting DNA supercoiling levels in different strains of C. jejuni, and relaxation of DNA supercoiling resulted in decreased motility. Transcriptional analysis and Western immunoblotting revealed that a reduction in motility and DNA supercoiling affected the two-component regulatory system FlgRS and was associated with reduced FlgR expression, increased FlgS expression, and aberrant expression of flagellin subunits. Electron microscopy revealed that the flagellar structure remained intact. Growth in the presence of porcine mucin resulted in increased negative supercoiling, increased motility, increased FlgR expression, and reduced FlgS expression. Finally, this supercoiling-dependent regulon was shown to be induced by growth in chicken mucus, and the level of activation was dependent on the source of the mucus from within the chicken intestinal tract. In conclusion, this study reports for the first time the key role played by DNA supercoiling in regulating motility in C. jejuni and indicates that the induction of this supercoiling-induced regulon in response to mucus from different sources could play a critical role in regulating motility in vivo Although Campylobacter jejuni is the leading cause of bacterial gastroenteritis, very little is understood about how this pathogen controls the expression of genes involved in causing disease. This study for the first time identifies DNA supercoiling as a key regulator of motility in C. jejuni, which is essential for both pathogenesis and colonization. Altering the

  14. Development of the human infant intestinal microbiota.

    Directory of Open Access Journals (Sweden)

    Chana Palmer

    2007-07-01

    Full Text Available Almost immediately after a human being is born, so too is a new microbial ecosystem, one that resides in that person's gastrointestinal tract. Although it is a universal and integral part of human biology, the temporal progression of this process, the sources of the microbes that make up the ecosystem, how and why it varies from one infant to another, and how the composition of this ecosystem influences human physiology, development, and disease are still poorly understood. As a step toward systematically investigating these questions, we designed a microarray to detect and quantitate the small subunit ribosomal RNA (SSU rRNA gene sequences of most currently recognized species and taxonomic groups of bacteria. We used this microarray, along with sequencing of cloned libraries of PCR-amplified SSU rDNA, to profile the microbial communities in an average of 26 stool samples each from 14 healthy, full-term human infants, including a pair of dizygotic twins, beginning with the first stool after birth and continuing at defined intervals throughout the first year of life. To investigate possible origins of the infant microbiota, we also profiled vaginal and milk samples from most of the mothers, and stool samples from all of the mothers, most of the fathers, and two siblings. The composition and temporal patterns of the microbial communities varied widely from baby to baby. Despite considerable temporal variation, the distinct features of each baby's microbial community were recognizable for intervals of weeks to months. The strikingly parallel temporal patterns of the twins suggested that incidental environmental exposures play a major role in determining the distinctive characteristics of the microbial community in each baby. By the end of the first year of life, the idiosyncratic microbial ecosystems in each baby, although still distinct, had converged toward a profile characteristic of the adult gastrointestinal tract.

  15. Functional Analysis of Lactobacillus rhamnosus GG Pili in Relation to Adhesion and Immunomodulatory Interactions with Intestinal Epithelial Cells

    NARCIS (Netherlands)

    Lebeer, S.; Claes, I.J.; Tytgat, H.L.P.; Verhoeven, T.L.A.; Marien, E.; Ossowski, von I.; Reunanen, J.; Palva, A.; Vos, de W.M.; Keersmaecker, de S.C.; Vanderleyden, J.

    2012-01-01

    Lactobacillus rhamnosus GG, a probiotic with good survival capacity in the human gut, has well-documented adhesion properties and health effects. Recently, spaCBA-encoded pili that bind to human intestinal mucus were identified on its cell surface. Here, we report on the phenotypic analysis of a

  16. Functional Analysis of Lactobacillus rhamnosus GG Pili in Relation to Adhesion and Immunomodulatory Interactions with Intestinal Epithelial Cells

    NARCIS (Netherlands)

    Lebeer, S.; Claes, I.J.; Tytgat, H.L.P.; Verhoeven, T.L.A.; Marien, E.; Ossowski, von I.; Reunanen, J.; Palva, A.; Vos, de W.M.; Keersmaecker, de S.C.; Vanderleyden, J.

    2012-01-01

    Lactobacillus rhamnosus GG, a probiotic with good survival capacity in the human gut, has well-documented adhesion properties and health effects. Recently, spaCBA-encoded pili that bind to human intestinal mucus were identified on its cell surface. Here, we report on the phenotypic analysis of a spa

  17. Intravenous Glucose Acutely Stimulates Intestinal Lipoprotein Secretion in Healthy Humans.

    Science.gov (United States)

    Xiao, Changting; Dash, Satya; Morgantini, Cecilia; Lewis, Gary F

    2016-07-01

    Increased production of intestinal triglyceride-rich lipoproteins (TRLs) contributes to dyslipidemia and increased risk of atherosclerotic cardiovascular disease in insulin resistance and type 2 diabetes. We have previously demonstrated that enteral glucose enhances lipid-stimulated intestinal lipoprotein particle secretion. Here, we assessed whether glucose delivered systemically by intravenous infusion also enhances intestinal lipoprotein particle secretion in humans. On 2 occasions, 4 to 6 weeks apart and in random order, 10 healthy men received a constant 15-hour intravenous infusion of either 20% glucose to induce hyperglycemia or normal saline as control. Production of TRL-apolipoprotein B48 (apoB48, primary outcomes) and apoB100 (secondary outcomes) was assessed during hourly liquid-mixed macronutrient formula ingestion with stable isotope enrichment and multicompartmental modeling, under pancreatic clamp conditions to limit perturbations in pancreatic hormones (insulin and glucagon) and growth hormone. Compared with saline infusion, glucose infusion induced both hyperglycemia and hyperinsulinemia, increased plasma triglyceride levels, and increased TRL-apoB48 concentration and production rate (Plipoprotein production. Hyperglycemia may contribute to intestinal lipoprotein overproduction in type 2 diabetes. URL: http://www.clinicaltrials.gov. Unique identifier: NCT02607839. © 2016 American Heart Association, Inc.

  18. Lactobacillus strains belonging to Casei group display various adherence to enterocytes and mucus

    Directory of Open Access Journals (Sweden)

    Corinna Markowicz

    2015-09-01

    Full Text Available Background. The ability of lactobacilli to adhere to the surface of the intestine is an important functional characteristic which can largely determine the effective colonization of the intestinal tract by probiotics. The following study compares the adhesion efficiency of the twenty strains of Lactobacillus genus belonging to Casei group to the Caco-2 cells and gastrointestinal mucus. Material and methods. Twenty isolates of lactobacilli belonging to Casei group were tested. The ability of bacterial cells to adhere to mucus was examined using adhesion assay to gastrointestinal mucus. Obtained results were compared with adhesion efficiency to Caco-2 cells. Phylogenetic relationship between isolates was analysed by rep-PCR. Results. The results showed large differences in adhesion efficiency between strains, as well as differences in the efficiency of adhesion to the intestinal epithelial cells and mucus. Group similarity highlighted by a rep-PCR technique does not correspond with groups of similarity in terms of the characteristics of the ability to adhere to mucus or the epithelial cells of intestinal tract. Conclusions. Strains having a high adhesion efficiency to enterocytes do not always show a high adhesion efficiency to the mucus. This may indicate the presence of different and multiple factors responsible for adhesion efficiency of Lactobacillus group Casei strains to epithelial cells and mucus.

  19. Evolution of symbiotic bacteria in the distal human intestine.

    Directory of Open Access Journals (Sweden)

    Jian Xu

    2007-07-01

    Full Text Available The adult human intestine contains trillions of bacteria, representing hundreds of species and thousands of subspecies. Little is known about the selective pressures that have shaped and are shaping this community's component species, which are dominated by members of the Bacteroidetes and Firmicutes divisions. To examine how the intestinal environment affects microbial genome evolution, we have sequenced the genomes of two members of the normal distal human gut microbiota, Bacteroides vulgatus and Bacteroides distasonis, and by comparison with the few other sequenced gut and non-gut Bacteroidetes, analyzed their niche and habitat adaptations. The results show that lateral gene transfer, mobile elements, and gene amplification have played important roles in affecting the ability of gut-dwelling Bacteroidetes to vary their cell surface, sense their environment, and harvest nutrient resources present in the distal intestine. Our findings show that these processes have been a driving force in the adaptation of Bacteroidetes to the distal gut environment, and emphasize the importance of considering the evolution of humans from an additional perspective, namely the evolution of our microbiomes.

  20. Mimicking microbial strategies for the design of mucus-permeating nanoparticles for oral immunization.

    Science.gov (United States)

    Gamazo, Carlos; Martín-Arbella, Nekane; Brotons, Ana; Camacho, Ana I; Irache, J M

    2015-10-01

    Dealing with mucosal delivery systems means dealing with mucus. The name mucosa comes from mucus, a dense fluid enriched in glycoproteins, such as mucin, which main function is to protect the delicate mucosal epithelium. Mucus provides a barrier against physiological chemical and physical aggressors (i.e., host secreted digestive products such as bile acids and enzymes, food particles) but also against the potentially noxious microbiota and their products. Intestinal mucosa covers 400m(2) in the human host, and, as a consequence, is the major portal of entry of the majority of known pathogens. But, in turn, some microorganisms have evolved many different approaches to circumvent this barrier, a direct consequence of natural co-evolution. The understanding of these mechanisms (known as virulence factors) used to interact and/or disrupt mucosal barriers should instruct us to a rational design of nanoparticulate delivery systems intended for oral vaccination and immunotherapy. This review deals with this mimetic approach to obtain nanocarriers capable to reach the epithelial cells after oral delivery and, in parallel, induce strong and long-lasting immune and protective responses.

  1. Functional Metagenomic Investigations of the Human Intestinal Microbiota

    Directory of Open Access Journals (Sweden)

    Aimee Marguerite Moore

    2011-10-01

    Full Text Available The human intestinal microbiota encode multiple critical functions impacting human health, including, metabolism of dietary substrate, prevention of pathogen invasion, immune system modulation, and provision of a reservoir of antibiotic resistance genes accessible to pathogens. The complexity of this microbial community, its recalcitrance to standard cultivation and the immense diversity of its encoded genes has necessitated the development of novel molecular, microbiological, and genomic tools. Functional metagenomics is one such culture-independent technique used for decades to study environmental microorganisms but relatively recently applied to the study of the human commensal microbiota. Metagenomic functional screens characterize the functional capacity of a microbial community independent of identity to known genes by subjecting the metagenome to functional assays in a genetically tractable host. Here we highlight recent work applying this technique to study the functional diversity of the intestinal microbiota, and discuss how an approach combining high-throughput sequencing, cultivation, and metagenomic functional screens can improve our understanding of interactions between this complex community and its human host.

  2. Human Milk Hyaluronan Enhances Innate Defense of the Intestinal Epithelium*

    Science.gov (United States)

    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

  3. Human milk hyaluronan enhances innate defense of the intestinal epithelium.

    Science.gov (United States)

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

    2013-10-04

    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.

  4. Intestinal microbiota modulates gluten-induced immunopathology in humanized mice.

    Science.gov (United States)

    Galipeau, Heather J; McCarville, Justin L; Huebener, Sina; Litwin, Owen; Meisel, Marlies; Jabri, Bana; Sanz, Yolanda; Murray, Joseph A; Jordana, Manel; Alaedini, Armin; Chirdo, Fernando G; Verdu, Elena F

    2015-11-01

    Celiac disease (CD) is an immune-mediated enteropathy triggered by gluten in genetically susceptible individuals. The recent increase in CD incidence suggests that additional environmental factors, such as intestinal microbiota alterations, are involved in its pathogenesis. However, there is no direct evidence of modulation of gluten-induced immunopathology by the microbiota. We investigated whether specific microbiota compositions influence immune responses to gluten in mice expressing the human DQ8 gene, which confers moderate CD genetic susceptibility. Germ-free mice, clean specific-pathogen-free (SPF) mice colonized with a microbiota devoid of opportunistic pathogens and Proteobacteria, and conventional SPF mice that harbor a complex microbiota that includes opportunistic pathogens were used. Clean SPF mice had attenuated responses to gluten compared to germ-free and conventional SPF mice. Germ-free mice developed increased intraepithelial lymphocytes, markers of intraepithelial lymphocyte cytotoxicity, gliadin-specific antibodies, and a proinflammatory gliadin-specific T-cell response. Antibiotic treatment, leading to Proteobacteria expansion, further enhanced gluten-induced immunopathology in conventional SPF mice. Protection against gluten-induced immunopathology in clean SPF mice was reversed after supplementation with a member of the Proteobacteria phylum, an enteroadherent Escherichia coli isolated from a CD patient. The intestinal microbiota can both positively and negatively modulate gluten-induced immunopathology in mice. In subjects with moderate genetic susceptibility, intestinal microbiota changes may be a factor that increases CD risk.

  5. Diversity of human small intestinal Streptococcus and Veillonella populations.

    Science.gov (United States)

    van den Bogert, Bartholomeus; Erkus, Oylum; Boekhorst, Jos; de Goffau, Marcus; Smid, Eddy J; Zoetendal, Erwin G; Kleerebezem, Michiel

    2013-08-01

    Molecular and cultivation approaches were employed to study the phylogenetic richness and temporal dynamics of Streptococcus and Veillonella populations in the small intestine. Microbial profiling of human small intestinal samples collected from four ileostomy subjects at four time points displayed abundant populations of Streptococcus spp. most affiliated with S. salivarius, S. thermophilus, and S. parasanguinis, as well as Veillonella spp. affiliated with V. atypica, V. parvula, V. dispar, and V. rogosae. Relative abundances varied per subject and time of sampling. Streptococcus and Veillonella isolates were cultured using selective media from ileostoma effluent samples collected at two time points from a single subject. The richness of the Streptococcus and Veillonella isolates was assessed at species and strain level by 16S rRNA gene sequencing and genetic fingerprinting, respectively. A total of 160 Streptococcus and 37 Veillonella isolates were obtained. Genetic fingerprinting differentiated seven Streptococcus lineages from ileostoma effluent, illustrating the strain richness within this ecosystem. The Veillonella isolates were represented by a single phylotype. Our study demonstrated that the small intestinal Streptococcus populations displayed considerable changes over time at the genetic lineage level because only representative strains of a single Streptococcus lineage could be cultivated from ileostoma effluent at both time points.

  6. Human milk and infant intestinal mucosal glycans guide succession of the neonatal intestinal microbiota.

    Science.gov (United States)

    Newburg, David S; Morelli, Lorenzo

    2015-01-01

    Infants begin acquiring intestinal microbiota at parturition. Initial colonization by pioneer bacteria is followed by active succession toward a dynamic ecosystem. Keystone microbes engage in reciprocal transkingdom communication with the host, which is essential for human homeostasis and health; therefore, these bacteria should be considered mutualists rather than commensals. This review discusses the maternal role in providing infants with functional and stable microbiota. The initial fecal inoculum of microbiota results from the proximity of the birth canal and anus; the biological significance of this anatomic proximity could underlie observed differences in microbiota between vaginal and cesarean birth. Secondary sources of inocula include mouths and skin of kin, animals and objects, and the human milk microbiome, but guiding microbial succession may be a primary role of human milk. The unique glycans of human milk cannot be digested by the infant, but are utilized by mutualist bacteria. These prebiotic glycans support expansion of mutualist microbiota, which manifests as differences in microbiota among breastfed and artificially fed infants. Human milk glycans vary by maternal genotype. Milks of genetically distinct mothers and variations in infant mucosal glycan expression support discrete microbiota. Early colonization may permanently influence microbiota composition and function, with ramifications for health.

  7. Detection of mucus glycoconjugates in human conjunctiva by using the lectin-colloidal gold technique in TEM. III. A quantitative study in asymptomatic contact lens wearers.

    Science.gov (United States)

    Versura, P; Maltarello, M C; Cellini, M; Marinelli, F; Caramazza, R; Laschi, R

    1987-12-01

    We characterized the mucus glycoconjugates produced by goblet and non-goblet epithelial cells in asymptomatic contact lens (CL) wearers. We employed four lectins (proteins of vegetal origin which specifically recognize glycosidic residues: WGA, PNA, SBA and ConA) conjugated with colloidal gold as ultrastructural marker, at Transmission Electron Microscopy. A computerized quantitative analysis was carried out in order to compare the results from the CL wearers to those from the control patients. Goblet cells produce different amount of glycosidic residues, in particular, a significant decrease in the distribution of sialic acid, N-acetylglucosamine, N-acetylgalactosamine, galactose-N-acetylgalactosamine and mannose was observed. The content of glycosidic residues in the mucus vesicles of the non-goblet epithelial cells appeared unchanged as to the normal situation. We speculate that the CL could possibly contribute to the failure of the tear film stability by altering the production of mucus.

  8. Detection of mucus glycoconjugates in human conjunctiva by using the lectin-colloidal gold technique in TEM. II. A quantitative study in dry-eye patients.

    Science.gov (United States)

    Versura, P; Maltarello, M C; Cellini, M; Caramazza, R; Laschi, R

    1986-08-01

    The mucus glycoconjugates produced by conjunctival goblet cells in dry-eye patients were studied by a specific cytochemical reaction in Transmission Electron Microscopy (TEM). Four lectins, proteins of vegetal origin which specifically bind glycosidic residues, (WGA, PNA, SBA and ConA) were used conjugated with colloidal gold as ultrastructural marker. We performed a quantitative analysis by counting the colloidal gold particles present on mucus granules. The results were compared with normal conditions. We found a decrease in sialic acid, N-acetyl-glucosamine, N-acetyl-galactosamine and galactose-N-acetyl-galactosamine and an increase in mannose. The different content of glycoconjugates in goblet cells may reflect in the change of physical and functional properties of mucus. We think these data may be useful in the search for a therapeutic mucomimetic drug.

  9. Human Enteroids/Colonoids and Intestinal Organoids Functionally Recapitulate Normal Intestinal Physiology and Pathophysiology

    NARCIS (Netherlands)

    O. Kovbasnjuk (Olga); N.C. Zachos (Nicholas C.); J. Foulke-Abel (Jennifer); J. In (Julie); E. Blutt, E. (Sarah); H.R. de Jonge (Hugo); M. Estes (Mary); M. Donowitz (Mark)

    2015-01-01

    markdownabstractIdentification of Lgr5 as the intestinal stem cell marker as well as the growth factors necessary to replicate adult intestinal stem cell division has led to the establishment of the methods to generate “indefinite” ex vivo primary intestinal epithelial cultures, termed “mini-intesti

  10. Vasoactive intestinal peptide signaling axis in human leukemia

    Institute of Scientific and Technical Information of China (English)

    Glenn; Paul; Dorsam; Keith; Benton; Jarrett; Failing; Sandeep; Batra

    2011-01-01

    The vasoactive intestinal peptide (VIP) signaling axis constitutes a master "communication coordinator" between cells of the nervous and immune systems.To date,VIP and its two main receptors expressed in T lymphocytes,vasoactive intestinal peptide receptor (VPAC)1 and VPAC2,mediate critical cellular functions regulating adaptive immunity,including arresting CD4 T cells in G 1 of the cell cycle,protection from apoptosis and a potent chemotactic recruiter of T cells to the mucosa associated lymphoid compartment of the gastrointestinal tissues.Since the discovery of VIP in 1970,followed by the cloning of VPAC1 and VPAC2 in the early 1990s,this signaling axis has been associated with common human cancers,including leukemia.This review highlights the present day knowledge of the VIP ligand and its receptor expression profile in T cell leukemia and cell lines.Also,there will be a discussion describing how the anti-leukemic DNA binding transcription factor,Ikaros,regulates VIP receptor expression in primary human CD4 T lymphocytes and T cell lymphoblastic cell lines (e.g.Hut-78).Lastly,future goals will be mentioned that are expected to uncover the role of how the VIP signaling axis contributes to human leukemogenesis,and to establish whether the VIP receptor signature expressed by leukemic blasts can provide therapeutic and/or diagnostic information.

  11. New developments in goblet cell mucus secretion and function.

    Science.gov (United States)

    Birchenough, G M H; Johansson, M E V; Gustafsson, J K; Bergström, J H; Hansson, G C

    2015-07-01

    Goblet cells and their main secretory product, mucus, have long been poorly appreciated; however, recent discoveries have changed this and placed these cells at the center stage of our understanding of mucosal biology and the immunology of the intestinal tract. The mucus system differs substantially between the small and large intestine, although it is built around MUC2 mucin polymers in both cases. Furthermore, that goblet cells and the regulation of their secretion also differ between these two parts of the intestine is of fundamental importance for a better understanding of mucosal immunology. There are several types of goblet cell that can be delineated based on their location and function. The surface colonic goblet cells secrete continuously to maintain the inner mucus layer, whereas goblet cells of the colonic and small intestinal crypts secrete upon stimulation, for example, after endocytosis or in response to acetyl choline. However, despite much progress in recent years, our understanding of goblet cell function and regulation is still in its infancy.

  12. Human intestinal epithelial cells produce proinflammatory cytokines in response to infection in a SCID mouse-human intestinal xenograft model of amebiasis.

    Science.gov (United States)

    Seydel, K B; Li, E; Swanson, P E; Stanley, S L

    1997-01-01

    The protozoan parasite Entamoeba histolytica causes amebic dysentery and amebic liver abscess, diseases associated with significant morbidity and mortality worldwide. E. histolytica infection appears to involve the initial attachment of amebic trophozoites to intestinal epithelial cells, followed by lysis of these cells and subsequent invasion into the submucosa. A recent in vitro study (L. Eckmann, S. L. Reed, J. R. Smith, and M. F. Kagnoff, J. Clin. Invest. 96:1269-1279, 1995) demonstrated that incubation of E. histolytica trophozoites with epithelial cell lines results in epithelial cell production of inflammatory cytokines, including interleukin-1 (IL-1) and IL-8, suggesting that intestinal epithelial cell production of cytokines might play a role in the inflammatory response and tissue damage seen in intestinal amebiasis. To determine whether intestinal epithelial cell production of IL-1 and IL-8 occurs in response to E. histolytica infection in vivo and as an approach to studying the specific interactions between amebic trophozoites and human intestine, we used a SCID mouse-human intestinal xenograft (SCID-HU-INT) model of disease, where human intestinal xenografts were infected with virulent E. histolytica trophozoites. Infection of xenografts with E. histolytica trophozoites resulted in extensive tissue damage, which was associated with the development of an early inflammatory response composed primarily of neutrophils. Using oligonucleotide primers that specifically amplify human IL-1beta and IL-8, we could demonstrate by reverse transcription PCR that mRNA for both IL-1beta and IL-8 is produced by human intestinal xenografts in response to amebic infection. The increase in human intestinal IL-1beta and IL-8 in response to invasive amebiasis was confirmed by enzyme-linked immunosorbent assays specific for human IL-1beta and IL-8. Using immunohistochemistry, we confirmed that human intestinal epithelial cells were the source of IL-8 in infected xenografts

  13. First report of human intestinal sarcocystosis in Cambodia.

    Science.gov (United States)

    Khieu, Virak; Marti, Hanspeter; Chhay, Saomony; Char, Meng Chuor; Muth, Sinuon; Odermatt, Peter

    2017-10-01

    Human intestinal sarcocystosis (HIS), caused by Sarcocystis species, is acquired by eating undercooked meat from sarcocyst-containing cattle (S. hominis, S. heydorni) and pigs (S. suihominis). We report on the detection of human intestinal Sarcocystis infections in a cross-sectional survey of Strongyloides stercoralis in early 2014, in Rovieng District, Preah Vihear Province, northern Cambodia. Among 1081 participants, 108 (10.0%) were diagnosed with Sarcocystis spp. oocysts in stool samples. Males had a significantly higher risk of infection than females (OR: 1.9, 95% CI: 1.3-2.9, p=0.001). None of the reported symptoms (abdominal discomfort, diarrhea, muscle pain and itching skin) occurring in the two weeks preceding the examinations were associated with a Sarcocystis infection. Many Sarcocystis cases were found among those who had participated in a wedding celebration and Chinese New Year festivities, where they had consumed raw or insufficiently cooked beef (83.3%) and pork (38.9%) based dishes. This report documents the first HIS cases in Cambodia. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Transgenic Expression of Human Lysophosphatidic Acid Receptor LPA2 in Mouse Intestinal Epithelial Cells Induces Intestinal Dysplasia.

    Directory of Open Access Journals (Sweden)

    Michihiro Yoshida

    Full Text Available Lysophosphatidic acid (LPA acts on LPA2 receptor to mediate multiple pathological effects that are associated with tumorigenesis. The absence of LPA2 attenuates tumor progression in rodent models of colorectal cancer, but whether overexpression of LPA2 alone can lead to malignant transformation in the intestinal tract has not been studied. In this study, we expressed human LPA2 in intestinal epithelial cells (IECs under control of the villin promoter. Less than 4% of F1-generation mice had germline transmission of transgenic (TG human LPA2; as such only 3 F1 mice out of 72 genotyped had TG expression. These TG mice appeared anemic with hematochezia and died shortly after birth. TG mice were smaller in size compared with the wild type mouse of the same age and sex. Morphological analysis showed that TG LPA2 colon had hyper-proliferation of IECs resulting in increased colonic crypt depth. Surprisingly, TG small intestine had villus blunting and decreased IEC proliferation and dysplasia. In both intestine and colon, TG expression of LPA2 compromised the terminal epithelial differentiation, consistent with epithelial dysplasia. Furthermore, we showed that epithelial dysplasia was observed in founder mouse intestine, correlating LPA2 overexpression with epithelial dysplasia. The current study demonstrates that overexpression of LPA2 alone can lead to intestinal dysplasia.

  15. Prediction of drug intestinal absorption in human using the Ussing chamber system: A comparison of intestinal tissues from animals and humans.

    Science.gov (United States)

    Miyake, Masateru; Koga, Toshihisa; Kondo, Satoshi; Yoda, Noriaki; Emoto, Chie; Mukai, Tadashi; Toguchi, Hajime

    2017-01-01

    An adequate evaluation system for drug intestinal absorption is essential in the pharmaceutical industry. Previously, we established a novel prediction system of drug intestinal absorption in humans, using the mini-Ussing chamber equipped with human intestinal tissues. In this system, the TI value was defined as the sum of drug amounts transported to the basal-side component (X(corr)) and drug amounts accumulated in the tissue (T(corr)), which are normalized by AUC of a drug in the apical compartment, as an index for drug absorption. In order to apply this system to the screening assay, it is important to understand the differences between animal and human tissues in the intestinal absorption of drugs. In this study, the transport index (TI) values of three drugs, with different levels of membrane permeability, were determined to evaluate the rank order of drug absorbability in intestinal tissues from rats, dogs, and monkeys. The TI values in small intestinal tissues in rats and dogs showed a good correlation with those in humans. On the other hand, the correlation of TI values in monkeys was lower compared to rats and dogs. The rank order of the correlation coefficient between human and investigated animal tissues was as follows: dog (r(2)=0.978), rat (r(2)=0.955), and monkey (r(2)=0.620). TI values in large intestinal tissues from rats (r(2)=0.929) and dogs (r(2)=0.808) also showed a good correlation. The obtained TI values in small intestinal tissues in rats and dogs were well correlated with the fraction of drug absorbed (Fa) in humans. From these results, the mini-Ussing chamber, equipped with intestinal tissues in rats and dogs, would be useful as a screening tool in the drug discovery stage. In addition, the obtained TI values can be used for the prediction of the Fa in humans. Copyright © 2016 Elsevier B.V. All rights reserved.

  16. Mucus as a Barrier to Drug Delivery

    DEFF Research Database (Denmark)

    Bøgh, Marie; Nielsen, Hanne Mørck

    2015-01-01

    Viscoelastic mucus lines all mucosal surfaces of the body and forms a potential barrier to mucosal drug delivery. Mucus is mainly composed of water and mucins; high-molecular weight glycoproteins forming an entangled network. Consequently, mucus forms a steric barrier and due to its negative charge...... and hydrophobic domains, the overall hydrophilic mucus also presents an interactive barrier limiting the free diffusion of components within and through the mucus. Furthermore, mucus is a dynamic barrier due to its continuous secretion and shedding from the mucosal surfaces. Mucus is thus a highly complex gel......, studies of peptide and protein drug diffusion in and through mucus and studies of mucus-penetrating nanoparticles are included to illustrate the mucus as a potentially important barrier to obtain sufficient bioavailability of orally administered drugs, and thus an important parameter to address...

  17. INTESTINAL VIROME AND NORMAL MICROFLORA OF HUMAN: FEATURES OF INTERACTION

    Directory of Open Access Journals (Sweden)

    Bobyr V.V.

    2015-05-01

    Full Text Available Summary: Intestinal bacteria defend the host organism and narrow pathogenic bacterial colonization. However, the microbiome effect to enteric viruses is unexplored largely as well as role of microbiota in the pathogenesis of viral infections in general. This review focuses on precisely these issues. Keywords: microbiome, virome, normal microflora, enteric viruses, contagiousness. In this review article, facts about viral persistence in the human gut are summarized. It is described the role of viral populations during health and diseases. After analyzing of the literary facts it was concluded that the gastrointestinal tract is an environment for one from the most complex microbial ecosystems, which requires of more deeper study of its composition, role in physiological processes, as well as the dynamics of changes under influence of the environment. Normal microflora performs a different important functions providing the physiological homeostasis of the human body, including, in particular, an important role in the human metabolic processes, supporting of homeostasis, limiting of colonization by infectious bacteria. The multifactorial significance of the normal gastrointestinal microflora can be divided into immunological, structural and metabolic functions. At the same time, interaction between intestinal microflora and enteric viruses has not been studied largely. In recent years, much attention is paid to study of viruses-bacteria associations, and it is possible, obtained results should change our understanding of microbiota role in the systematic pathogenesis of the diseases with viral etiology. In contrast to the well-known benefits of normal microflora to the host, the viruses can use intestinal microflora as a trigger for replication at the optimal region. Recent studies give a reason for assumption that depletion of normal microflora with antibiotics can determining the antiviral effect. Thus, the role of commensal bacteria in viral

  18. The predominant cholecystokinin in human plasma and intestine is cholecystokinin-33

    DEFF Research Database (Denmark)

    Rehfeld, J F; Sun, G; Christensen, T;

    2001-01-01

    Cholecystokinin (CCK) occurs in multiple molecular forms; the major ones are CCK-58, -33, -22, and -8. Their relative abundance in human plasma and intestine, however, is debated. To settle the issue, extracts of intestinal biopsies and plasma from 10 human subjects have been examined...... is the second most abundant ( approximately 34% and 30%, respectively). In contrast, CCK-58 is less abundant in human intestines ( approximately 18%) and plasma ( approximately 11%). Its predominance in feline intestines, however, was confirmed. Hence, the results show a significant species variation...

  19. A revised model for electron dosimetry in the human small intestine.

    Science.gov (United States)

    Bhuiyan, N U; Poston, J W

    2005-01-01

    In this study, the absorbed dose was calculated to the small intestine (SI) wall of an adult human from electrons in its lumen contents. The effects on dose due to variations in the lumen radius and wall-thickness also were studied. The SI model was based on values gleaned from anatomic and histologic reviews of the adult human SI. Histologic and radiological analyses of the SI suggested the microscopic intricacy of this walled organ could be avoided for dosimetric purposes and a set of concentric cylinders could be used to model the SI. The model was input into the Monte Carlo N-Particle (MCNP) version 4A computational package, which was used to simulate energy deposition in the SI by electrons of fifty discrete energies ranging 10-500 keV. The source electrons as well as all resulting particles, such as knock-on electrons, bremsstrahlung, and electrons created from bremsstrahlung interactions, were transported until the particle energies fell below the 1 keV low-energy cutoff. Detailed physics treatments for secondary photons were made. With a reasonable number of histories, appropriate variance reduction techniques were used to improve the precision of the Monte Carlo calculations. The model used very small tally regions, which ranged in thickness from 0.5 microm to 200 microm depending on the electron energy studied and tally location in the wall. Relative errors associated with these calculations were maintained at less than 5%. The large number of tally results across the wall for each of the energies studied enabled the construction of the energy-specific depth dose curves in the wall. Each of these curves was consistent with the anticipated energy deposition pattern. These curves showed that only a small fraction of the energy absorbed at the contents-mucus interface reaches the stem cell layers because the cells are located deep in the mucosa. This fraction was found to vary from 1.66 x 10(-6) to 1.21 x 10(-1) over the energy range 10-500 keV. These

  20. Human and mouse tissue-engineered small intestine both demonstrate digestive and absorptive function.

    Science.gov (United States)

    Grant, Christa N; Mojica, Salvador Garcia; Sala, Frederic G; Hill, J Ryan; Levin, Daniel E; Speer, Allison L; Barthel, Erik R; Shimada, Hiroyuki; Zachos, Nicholas C; Grikscheit, Tracy C

    2015-04-15

    Short bowel syndrome (SBS) is a devastating condition in which insufficient small intestinal surface area results in malnutrition and dependence on intravenous parenteral nutrition. There is an increasing incidence of SBS, particularly in premature babies and newborns with congenital intestinal anomalies. Tissue-engineered small intestine (TESI) offers a therapeutic alternative to the current standard treatment, intestinal transplantation, and has the potential to solve its biggest challenges, namely donor shortage and life-long immunosuppression. We have previously demonstrated that TESI can be generated from mouse and human small intestine and histologically replicates key components of native intestine. We hypothesized that TESI also recapitulates native small intestine function. Organoid units were generated from mouse or human donor intestine and implanted into genetically identical or immunodeficient host mice. After 4 wk, TESI was harvested and either fixed and paraffin embedded or immediately subjected to assays to illustrate function. We demonstrated that both mouse and human tissue-engineered small intestine grew into an appropriately polarized sphere of intact epithelium facing a lumen, contiguous with supporting mesenchyme, muscle, and stem/progenitor cells. The epithelium demonstrated major ultrastructural components, including tight junctions and microvilli, transporters, and functional brush-border and digestive enzymes. This study demonstrates that tissue-engineered small intestine possesses a well-differentiated epithelium with intact ion transporters/channels, functional brush-border enzymes, and similar ultrastructural components to native tissue, including progenitor cells, whether derived from mouse or human cells.

  1. Common occurrence of antibacterial agents in human intestinal microbiota

    Directory of Open Access Journals (Sweden)

    Fatima eDrissi

    2015-05-01

    Full Text Available Laboratory experiments have revealed many active mechanisms by which bacteria can inhibit the growth of other organisms. Bacteriocins are a diverse group of natural ribosomally-synthesized antimicrobial peptides produced by a wide range of bacteria and which seem to play an important role in mediating competition within bacterial communities. In this study, we have identified and established the structural classification of putative bacteriocins encoded by 317 microbial genomes in the human intestine. On the basis of homologies to available bacteriocin sequences, mainly from lactic acid bacteria, we report the widespread occurrence of bacteriocins across the gut microbiota: 175 bacteriocins were found to be encoded in Firmicutes, 79 in Proteobacteria, 34 in Bacteroidetes and 25 in Actinobacteria. Bacteriocins from gut bacteria displayed wide differences among phyla with regard to class distribution, net positive charge, hydrophobicity and secondary structure, but the α-helix was the most abundant structure. The peptide structures and physiochemical properties of bacteriocins produced by the most abundant bacteria in the gut, the Firmicutes and the Bacteroidetes, seem to ensure low antibiotic activity and participate in permanent intestinal host defence against the proliferation of harmful bacteria. Meanwhile, the potentially harmful bacteria, including the Proteobacteria, displayed highly effective bacteriocins, probably supporting the virulent character of diseases. These findings highlight the eventual role played by bacteriocins in gut microbial competition and their potential place in antibiotic therapy.

  2. NFATc1 regulation of TRAIL expression in human intestinal cells.

    Directory of Open Access Journals (Sweden)

    Qingding Wang

    Full Text Available TNF-related apoptosis-inducing ligand (TRAIL; Apo2 has been shown to promote intestinal cell differentiation. Nuclear factor of activated T cells (NFAT participates in the regulation of a variety of cellular processes, including differentiation. Here, we examined the role of NFAT in the regulation of TRAIL in human intestinal cells. Treatment with a combination of phorbol 12-myristate 13-acetate (PMA plus the calcium ionophore A23187 (Io increased NFAT activation and TRAIL expression; pretreatment with the calcineurin inhibitor cyclosporine A (CsA, an antagonist of NFAT signaling, diminished NFAT activation and TRAIL induction. In addition, knockdown of NFATc1, NFATc2, NFATc3, and NFATc4 blocked PMA/Io increased TRAIL protein expression. Expression of NFATc1 activated TRAIL promoter activity and increased TRAIL mRNA and protein expression. Deletion of NFAT binding sites from the TRAIL promoter did not significantly abrogate NFATc1-increased TRAIL promoter activity, suggesting an indirect regulation of TRAIL expression by NFAT activation. Knockdown of NFATc1 increased Sp1 transcription factor binding to the TRAIL promoter and, importantly, inhibition of Sp1, by chemical inhibition or RNA interference, increased TRAIL expression. These studies identify a novel mechanism for TRAIL regulation by which activation of NFATc1 increases TRAIL expression through negative regulation of Sp1 binding to the TRAIL promoter.

  3. Excipient-mediated supersaturation stabilization in human intestinal fluids.

    Science.gov (United States)

    Bevernage, Jan; Forier, Thomas; Brouwers, Joachim; Tack, Jan; Annaert, Pieter; Augustijns, Patrick

    2011-04-04

    It was the purpose of this study to investigate excipient-mediated precipitation inhibition upon induction of supersaturation of poorly water-soluble drugs in aspirated human intestinal fluids (HIF) representing both the fasted and fed state. Etravirine, ritonavir, loviride, danazol and fenofibrate were selected as model compounds. For comparative purposes, precipitation inhibition was also evaluated in simple aqueous buffer, and in intestinal simulation media representative for the fasted and fed state (FaSSIF and FeSSIF, respectively). Supersaturation was induced in the test media containing predissolved excipient (HPMC-AS, HPMC-E5, HPMC-E50, HPMC-E4M, HPMC-P and PVP) at a defined degree of supersaturation (DS = 20) using the solvent shift method. The results illustrate that cellulosic polymers can reduce the precipitation rate and stabilize supersaturation in HIF. The extent of stabilization was compound and excipient dependent but independent of the nutritional state. Whenever excipient effects were observed, the predictive value of simple buffer or FaSSIF/FeSSIF was rather limited. In general, excipient-mediated precipitation inhibition was less pronounced in HIF compared to simple aqueous buffer or FaSSIF/FeSSIF. However, excipients showing no effect in simple aqueous buffer or FaSSIF/FeSSIF also proved to be ineffective in HIF, indicating the value of these simulation media in the elimination of excipients during formulation development.

  4. Community and genomic analysis of the human small intestine microbiota

    NARCIS (Netherlands)

    Bogert, van den B.

    2013-01-01

      Our intestinal tract is densely populated by different microbes, collectively called microbiota, of which the majority are bacteria. Research focusing on the intestinal microbiota often use fecal samples as a representative of the bacteria that inhabit the end of the large intestine. These s

  5. Ultrastructure of interstitial cells of Cajal in circular muscle of human small intestine

    DEFF Research Database (Denmark)

    Rumessen, J J; Mikkelsen, H B; Qvortrup, Klaus;

    1993-01-01

    Interstitial cells of Cajal (ICC) may be important regulatory cells in gut muscle layers. This study examined ICC within the circular muscle of human small intestine.......Interstitial cells of Cajal (ICC) may be important regulatory cells in gut muscle layers. This study examined ICC within the circular muscle of human small intestine....

  6. Advanced approaches to characterize the human intestinal microbiota by computational meta-analysis

    NARCIS (Netherlands)

    Nikkilä, J.; Vos, de W.M.

    2010-01-01

    GOALS: We describe advanced approaches for the computational meta-analysis of a collection of independent studies, including over 1000 phylogenetic array datasets, as a means to characterize the variability of human intestinal microbiota. BACKGROUND: The human intestinal microbiota is a complex micr

  7. Mucus Rupture in A Collapsed airway: An Experimental Study

    Science.gov (United States)

    Hu, Yingying; Bian, Shiyao; Grotberg, James B.

    2011-11-01

    Mucus plugs can completely obstruct an airway. Difficulty in mucus clearance results in lost gas exchange and inflammation. Non-Newtonian properties of mucus, yielding stress and shear-thinning, play significant roles in mucus clearance. We use aqueous carbopol 940 as a mucus stimulant to study clearance of a mucus plug with properties of yielding stress and shear-thinning in a bench-top experiment. A collapsed airway of the 12th generation in a human lung is simulated in a two-dimensional PDMS channel. A stable pressure drop is set along the plug to drive rupture. A micro-PIV technique is used to acquire velocity fields during the rupture process. A yielding pressure drop (initiating plug yielding) is nearly independent of initial plug length. Plug rupture can occur by focused deformation along the centerline or by total plug propagation where the trailing film is thicker than the precursor film. Maximum velocity appears at the rupture moment, and increases at higher pressure drop or smaller plug length. The wall shear gradient can undergo a rapid reversal when rupture occurs, possibly an injurious event to underlying airway epithelial cells. This work is supported by NIH: HL84370 and HL85156.

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

    Directory of Open Access Journals (Sweden)

    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.

  9. Metaproteomics of the Human Intestinal Tract to Assess Microbial Functionality and Interactions with the Host

    OpenAIRE

    Kolmeder, Carolin

    2015-01-01

    Human physiological processes are complemented by those of the microbiota, the collection of all microbes living in and on our body. The human intestinal microbiota is one of the most prominent representatives and many associations with a wide spectrum of human diseases have been identified. Analysing faecal material with nucleic acid based approaches revealed the species richness of the intestinal microbiota and its individuality, being unique to each human being. In addition, to date approx...

  10. Human in vivo regional intestinal permeability: quantitation using site-specific drug absorption data.

    Science.gov (United States)

    Sjögren, Erik; Dahlgren, David; Roos, Carl; Lennernäs, Hans

    2015-06-01

    Application of information on regional intestinal permeability has been identified as a key aspect of successful pharmaceutical product development. This study presents the results and evaluation of an approach for the indirect estimation of site-specific in vivo intestinal effective permeability (Peff) in humans. Plasma concentration-time profiles from 15 clinical studies that administered drug solutions to specific intestinal regions were collected and analyzed. The intestinal absorption rate for each drug was acquired by deconvolution, using historical intravenous data as reference, and used with the intestinal surface area and the dose remaining in the lumen to estimate the Peff. Forty-three new Peff values were estimated (15 from the proximal small intestine, 11 from the distal small intestine, and 17 from the large intestine) for 14 active pharmaceutical ingredients representing a wide range of biopharmaceutical properties. A good correlation (r(2) = 0.96, slope = 1.24, intercept = 0.030) was established between these indirect jejunal Peff estimates and jejunal Peff measurements determined directly using the single-pass perfusion double balloon technique. On average, Peff estimates from the distal small intestine and large intestine were 90% and 40%, respectively, of those from the proximal small intestine. These results support the use of the evaluated deconvolution method for indirectly estimating regional intestinal Peff in humans. This study presents the first comprehensive data set of estimated human regional intestinal permeability values for a range of drugs. These biopharmaceutical data can be used to improve the accuracy of gastrointestinal absorption predictions used in drug development decision-making.

  11. Effect of ceftobiprole on the normal human intestinal microflora.

    Science.gov (United States)

    Bäckström, Tobias; Panagiotidis, Georgios; Beck, Olof; Asker-Hagelberg, Charlotte; Rashid, Mamun-Ur; Weintraub, Andrej; Nord, Carl Erik

    2010-12-01

    Ceftobiprole is a new broad-spectrum pyrrolidinone cephem active against meticillin-resistant Staphylococcus aureus, vancomycin-resistant Enterococcus faecalis and Gram-negative bacteria such as Enterobacteriaceae and Pseudomonas spp. The purpose of the present study was to investigate the effect of administration of ceftobiprole on the normal intestinal microflora. Twelve healthy subjects (six males and six females) aged 20-31 years received ceftobiprole 500 mg by intravenous infusion every 8h for 7 days. Plasma samples were collected on Days -1, 1, 4, 7, 10, 14 and 21 for determination of drug concentration by biological and chemical methods. Faecal samples were collected on Days -1, 2, 4, 7, 10, 14 and 21. For analysis of the microflora, faecal specimens were cultured on non-selective and selective media. Different colony types were counted, isolated in pure culture and identified to genus level. All new colonising aerobic and anaerobic bacteria were tested for susceptibility to ceftobiprole. Plasma concentrations of ceftobiprole 10 min after completion of infusion were as follows: Day 1, 14.7-23.6 mg/L; Day 4, 15.9-24.5 mg/L; and Day 7, 15.9-23.9 mg/L. No ceftobiprole was detected in plasma on Days -1, 10, 14 and 21. No measurable concentrations of ceftobiprole were found in faeces on Days -1, 2, 4, 7, 10, 14 and 21. There were minor changes in the numbers of enteric bacteria, enterococci and Candida albicans and there were moderate changes in the numbers of bifidobacteria, lactobacilli, clostridia and Bacteroides spp. during the same period. No Clostridium difficile strains or toxins were found. No new colonising aerobic and anaerobic bacteria with ceftobiprole minimum inhibitory concentrations of ≥ 4 mg/L were found. Ceftobiprole had no significant ecological impact on the human intestinal microflora.

  12. Directed differentiation of human pluripotent stem cells into intestinal tissue in vitro.

    Science.gov (United States)

    Spence, Jason R; Mayhew, Christopher N; Rankin, Scott A; Kuhar, Matthew F; Vallance, Jefferson E; Tolle, Kathryn; Hoskins, Elizabeth E; Kalinichenko, Vladimir V; Wells, Susanne I; Zorn, Aaron M; Shroyer, Noah F; Wells, James M

    2011-02-03

    Studies in embryonic development have guided successful efforts to direct the differentiation of human embryonic and induced pluripotent stem cells (PSCs) into specific organ cell types in vitro. For example, human PSCs have been differentiated into monolayer cultures of liver hepatocytes and pancreatic endocrine cells that have therapeutic efficacy in animal models of liver disease and diabetes, respectively. However, the generation of complex three-dimensional organ tissues in vitro remains a major challenge for translational studies. Here we establish a robust and efficient process to direct the differentiation of human PSCs into intestinal tissue in vitro using a temporal series of growth factor manipulations to mimic embryonic intestinal development. This involved activin-induced definitive endoderm formation, FGF/Wnt-induced posterior endoderm pattering, hindgut specification and morphogenesis, and a pro-intestinal culture system to promote intestinal growth, morphogenesis and cytodifferentiation. The resulting three-dimensional intestinal 'organoids' consisted of a polarized, columnar epithelium that was patterned into villus-like structures and crypt-like proliferative zones that expressed intestinal stem cell markers. The epithelium contained functional enterocytes, as well as goblet, Paneth and enteroendocrine cells. Using this culture system as a model to study human intestinal development, we identified that the combined activity of WNT3A and FGF4 is required for hindgut specification whereas FGF4 alone is sufficient to promote hindgut morphogenesis. Our data indicate that human intestinal stem cells form de novo during development. We also determined that NEUROG3, a pro-endocrine transcription factor that is mutated in enteric anendocrinosis, is both necessary and sufficient for human enteroendocrine cell development in vitro. PSC-derived human intestinal tissue should allow for unprecedented studies of human intestinal development and disease.

  13. Human and simulated intestinal fluids as solvent systems to explore food effects on intestinal solubility and permeability.

    Science.gov (United States)

    Stappaerts, Jef; Wuyts, Benjamin; Tack, Jan; Annaert, Pieter; Augustijns, Patrick

    2014-10-15

    The mixed micelles and vesicles present in the intraluminal environment of the postprandial state exhibit suitable solubilizing capacities for lipophilic drugs. This increase in solubility, however, is accompanied by a decrease in the free fraction caused by micellar entrapment of these lipophilic compounds. In this study, both simulated and aspirated human intestinal fluids of fasted and fed state conditions were used to evaluate the influence of food on the intestinal disposition of a series of structurally related β-blockers, with varying logP values. Using the in situ intestinal perfusion technique with mesenteric blood sampling in rats, it was demonstrated that fed state conditions significantly decreased the absorptive flux of the more lipophilic compounds metoprolol, propranolol and carvedilol, whereas the influence on the flux of the hydrophilic β-blocker atenolol was limited. The solubility of BCS class II compound carvedilol was found to increase significantly in simulated and aspirated media of the fed state. Intestinal perfusions using intestinal media saturated with carvedilol, revealed a higher flux in the fasted state compared to the fed state, despite the higher solubility in the fed state. This study underscores the importance of addressing the complex nature of the behavior of compounds in the intraluminal environment in fasted and fed state conditions. Moreover, our data point out the value of studying the effect of food on both solubility and permeability using biorelevant experimental conditions.

  14. Biochemical characterization, antimicrobial and hemolytic studies on skin mucus of fresh water spiny eel Mastacembelus armatus

    Institute of Scientific and Technical Information of China (English)

    Venkatachalam Uthayakumar; Venkatachalam Ramasubramanian; Dhanabalan Senthilkumar; Ramasamy Harikrishnan

    2012-01-01

    Objective: To characterize the biochemical, antimicrobial and hemolytic activities of Mastacembalus armatus skin mucus. Methods: Antimicrobial and antifungal activities of mucus extractions against human and fish pathogens were tested along with ampicillin as control. Hemolytic activity of the extraction was evaluated against sheep and cow blood cells. Amino acid and fatty acid profiles were analyzed by HPLC and gas chromatography in the mucus of fish. SDS-PAGE analysis of mucus and muscle tissue was done. Oneway-ANOVA was performed against all extraction and pathogens, amino acids and fatty acids. Result: All the mucus extracts exhibited higher inhibitory activity than antibiotic ampicillin against bacterial and fungal pathogens. The hemolytic activity was increased with higher mucus concentrations in both sheep and cow blood cells. The protein content soluble and insoluble fractions of mucus were 63.22 μg/g and 55.79μg/g, respectively. Out of 17 amino acids leucine was higher (8.54 mole %) in soluble gel, and glutamic acid was higher (6.92 mole %) in the insoluble gel, Histidine was very low (i.e. 0.20 mole%) both in soluble and (0.30 mole %) insoluble gel. In SDS-PAGE analysis, 6 bands of mucus and 9 bands of muscle were observed. Conclusions: The soluble and insoluble proteins are responsible for antimicrobial and hemolytic activity, these results indicate that mucus gel was prospective applications in fish and human therapeutics.

  15. A biophysical basis for mucus solids concentration as a candidate biomarker for airways disease.

    Directory of Open Access Journals (Sweden)

    David B Hill

    Full Text Available In human airways diseases, including cystic fibrosis (CF and chronic obstructive pulmonary disease (COPD, host defense is compromised and airways inflammation and infection often result. Mucus clearance and trapping of inhaled pathogens constitute key elements of host defense. Clearance rates are governed by mucus viscous and elastic moduli at physiological driving frequencies, whereas transport of trapped pathogens in mucus layers is governed by diffusivity. There is a clear need for simple and effective clinical biomarkers of airways disease that correlate with these properties. We tested the hypothesis that mucus solids concentration, indexed as weight percent solids (wt%, is such a biomarker. Passive microbead rheology was employed to determine both diffusive and viscoelastic properties of mucus harvested from human bronchial epithelial (HBE cultures. Guided by sputum from healthy (1.5-2.5 wt% and diseased (COPD, CF; 5 wt% subjects, mucus samples were generated in vitro to mimic in vivo physiology, including intermediate range wt% to represent disease progression. Analyses of microbead datasets showed mucus diffusive properties and viscoelastic moduli scale robustly with wt%. Importantly, prominent changes in both biophysical properties arose at ∼4 wt%, consistent with a gel transition (from a more viscous-dominated solution to a more elastic-dominated gel. These findings have significant implications for: (1 penetration of cilia into the mucus layer and effectiveness of mucus transport; and (2 diffusion vs. immobilization of micro-scale particles relevant to mucus barrier properties. These data provide compelling evidence for mucus solids concentration as a baseline clinical biomarker of mucus barrier and clearance functions.

  16. The genome of Akkermansia muciniphila, a dedicated intestinal mucin degrader, and its use in exploring intestinal metagenomes.

    Science.gov (United States)

    van Passel, Mark W J; Kant, Ravi; Zoetendal, Erwin G; Plugge, Caroline M; Derrien, Muriel; Malfatti, Stephanie A; Chain, Patrick S G; Woyke, Tanja; Palva, Airi; de Vos, Willem M; Smidt, Hauke

    2011-03-03

    The human gastrointestinal tract contains a complex community of microbes, fulfilling important health-promoting functions. However, this vast complexity of species hampers the assignment of responsible organisms to these functions. Recently, Akkermansia muciniphila, a new species from the deeply branched phylum Verrucomicrobia, was isolated from the human intestinal tract based on its capacity to efficiently use mucus as a carbon and nitrogen source. This anaerobic resident is associated with the protective mucus lining of the intestines. In order to uncover the functional potential of A. muciniphila, its genome was sequenced and annotated. It was found to contain numerous candidate mucinase-encoding genes, but lacking genes encoding canonical mucus-binding domains. Numerous phage-associated sequences found throughout the genome indicate that viruses have played an important part in the evolution of this species. Furthermore, we mined 37 GI tract metagenomes for the presence, and genetic diversity of Akkermansia sequences. Out of 37, eleven contained 16S ribosomal RNA gene sequences that are >95% identical to that of A. muciniphila. In addition, these libraries were found to contain large amounts of Akkermansia DNA based on average nucleotide identity scores, which indicated in one subject co-colonization by different Akkermansia phylotypes. An additional 12 libraries also contained Akkermansia sequences, making a total of ∼16 Mbp of new Akkermansia pangenomic DNA. The relative abundance of Akkermansia DNA varied between intestinal tract.

  17. Human intestinal dendritic cells as controllers of mucosal immunity

    Directory of Open Access Journals (Sweden)

    David Bernardo

    2013-06-01

    Full Text Available Dendritic cells are the most potent, professional antigen-presenting cells in the body; following antigen presentation they control the type (proinflammatory/regulatory of immune response that will take place, as well as its location. Given their high plasticity and maturation ability in response to local danger signals derived from innate immunity, dendritic cells are key actors in the connection between innate immunity and adaptive immunity responses. In the gut dendritic cells control immune tolerance mechanisms against food and/or commensal flora antigens, and are also capable of initiating an active immune response in the presence of invading pathogens. Dendritic cells are thus highly efficient in controlling the delicate balance between tolerance and immunity in an environment so rich in antigens as the gut, and any factor involving these cells may impact their function, ultimately leading to the development of bowel conditions such as celiac disease or inflammatory bowel disease. In this review we shall summarize our understanding of human intestinal dendritic cells, their ability to express and induce migration markers, the various environmental factors modulating their properties, their subsets in the gut, and the problems entailed by their study, including identification strategies, differences between humans and murine models, and phenotypical variations along the gastrointestinal tract.

  18. Degradation of neohesperidin dihydrochalcone by human intestinal bacteria.

    Science.gov (United States)

    Braune, Annett; Engst, Wolfram; Blaut, Michael

    2005-03-09

    The degradation of neohesperidin dihydrochalcone by human intestinal microbiota was studied in vitro. Human fecal slurries converted neohesperidin dihydrochalcone anoxically to 3-(3-hydroxy-4-methoxyphenyl)propionic acid or 3-(3,4-dihydroxyphenyl)propionic acid. Two transient intermediates were identified as hesperetin dihydrochalcone 4'-beta-d-glucoside and hesperetin dihydrochalcone. These metabolites suggest that neohesperidin dihydrochalcone is first deglycosylated to hesperetin dihydrochalcone 4'-beta-d-glucoside and subsequently to the aglycon hesperetin dihydrochalcone. The latter is hydrolyzed to the corresponding 3-(3-hydroxy-4-methoxyphenyl)propionic acid and probably phloroglucinol. Eubacterium ramulus and Clostridium orbiscindens were not capable of converting neohesperidin dihydrochalcone. However, hesperetin dihydrochalcone 4'-beta-d-glucoside was converted by E. ramulus to hesperetin dihydrochalcone and further to 3-(3-hydroxy-4-methoxyphenyl)propionic acid, but not by C. orbiscindens. In contrast, hesperetin dihydrochalcone was cleaved to 3-(3-hydroxy-4-methoxyphenyl)propionic acid by both species. The latter reaction was shown to be catalyzed by the phloretin hydrolase from E. ramulus.

  19. High-throughput analysis of the impact of antibiotics on the human intestinal microbiota composition

    NARCIS (Netherlands)

    Ladirat, S.E.; Schols, H.A.; Nauta, A.; Schoterman, M.H.C.; Keijser, B.J.F.; Montijn, R.C.; Gruppen, H.; Schuren, F.H.J.

    2013-01-01

    Antibiotic treatments can lead to a disruption of the human microbiota. In this in-vitro study, the impact of antibiotics on adult intestinal microbiota was monitored in a new high-throughput approach: a fermentation screening-platform was coupled with a phylogenetic microarray analysis (Intestinal-

  20. Formation and blood supply of the large intestine in human neonates

    Directory of Open Access Journals (Sweden)

    Haina N.I.

    2008-01-01

    Full Text Available A study of the large intestine has been carried out on 24 specimens of human newborns. It has been established that the form and size of the neonates large intestine demonstrated a sidnificant individual variability. The hepatic and splenic flexures of the colon had different relations with the inferior border of the liver and spleen.

  1. Naturally occurring products of proglucagon 111-160 in the porcine and human small intestine

    DEFF Research Database (Denmark)

    Buhl, T; Thim, L; Kofod, Hans

    1988-01-01

    Recent studies have revealed that the glucagon gene is expressed in the mammalian intestine. Here it codes for "glicentin" (proglucagon 1-69) and a glucagon-like peptide, proglucagon 78-107, recently isolated from porcine intestine. We studied the fate of the remaining COOH-terminal part of progl...... that this is the structure of the naturally occurring human peptide....

  2. Microbial communities in the human small intestine: coupling diversity to metagenomics.

    Science.gov (United States)

    Booijink, Carien C G M; Zoetendal, Erwin G; Kleerebezem, Michiel; de Vos, Willem M

    2007-06-01

    The gastrointestinal tract is the main site where the conversion and absorption of food components takes place. The host-derived physiological processes and the residing microorganisms, especially in the small intestine, contribute to this nutrient supply. To circumvent sampling problems of the small intestine, several model systems have been developed to study microbial diversity and functionality in the small intestine. In addition, metagenomics offers novel possibilities to gain insight into the genetic potential and functional properties of these microbial communities. Here, an overview is presented of the most recent insights into the diversity and functionality of the microorganisms in the human gastrointestinal tract, with a focus on the small intestine.

  3. A Sensitive Medium-Throughput Method to Predict Intestinal Absorption in Humans Using Rat Intestinal Tissue Segments.

    Science.gov (United States)

    Da Silva, Laís Cristina; Da Silva, Taynara Lourenço; Antunes, Alisson Henrique; Rezende, Kênnia Rocha

    2015-09-01

    A range of in vitro, ex vivo, and in vivo approaches are currently used for drug development. Highly predictive human intestinal absorption models remain lagging behind the times because of numerous variables concerning permeability through gastrointestinal tract in humans. However, there is a clear need for a drug permeability model early in the drug development process that can balance the requirements for high throughput and effective predictive potential. The present study developed a medium throughput screening Snapwell (MTS-Snapwell) ex vivo model to provide an alternative method to classify drug permeability. Rat small intestine tissue segments were mounted in commercial Snapwell™ inserts. Unidirectional drug transport (A-B) was measured by collecting samples at different time points. Viability of intestinal tissue segments was measured by examining transepithelial electric resistance (TEER) and phenol red and caffeine transport. As a result, the apparent permeability (Papp; ×10(-6) cm/s) was determined for atenolol (10.7 ± 1.2), caffeine (17.6 ± 3.1), cimetidine (6.9 ± 0.1), metoprolol (12.6 ± 0.7), theophylline (15.3 ± 1.6) and, ranitidine (3.8 ± 0.4). All drugs were classified in high/low permeability according to Biopharmaceutics Classification System showing high correlation with human data (r = 0.89). These findings showed a high correlation with human data (r = 0.89), suggesting that this model has potential predictive capacity for paracellular and transcellular passively absorbed molecules.

  4. Involvement of Concentrative Nucleoside Transporter 1 in Intestinal Absorption of Trifluridine Using Human Small Intestinal Epithelial Cells.

    Science.gov (United States)

    Takahashi, Koichi; Yoshisue, Kunihiro; Chiba, Masato; Nakanishi, Takeo; Tamai, Ikumi

    2015-09-01

    TAS-102, which is effective for refractory metastatic colorectal cancer, is a combination drug of anticancer trifluridine (FTD; which is derived from pyrimidine nucleoside) and FTD-metabolizing enzyme inhibitor tipiracil hydrochloride (TPI) at a molecular ratio of 1:0.5. To evaluate the intestinal absorption mechanism of FTD, the uptake and transcellular transport of FTD by human small intestinal epithelial cell (HIEC) monolayer as a model of human intestinal epithelial cells was investigated. The uptake and membrane permeability of FTD by HIEC monolayers were saturable, Na(+) -dependent, and inhibited by nucleosides. These transport characteristics are mostly comparable with those of concentrative nucleoside transporters (CNTs). Moreover, the uptake of FTD by CNT1-expressing Xenopus oocytes was the highest among human CNT transporters. The obtained Km and Vmax values of FTD by CNT1 were 69.0 μM and 516 pmol/oocyte/30 min, respectively. The transcellular transport of FTD by Caco-2 cells, where CNT1 is heterologously expressed, from apical to basolateral side was greater than that by Mock cells. In conclusion, these results demonstrated that FTD exhibits high oral absorption by the contribution of human CNT1. © 2015 Wiley Periodicals, Inc. and the American Pharmacists Association.

  5. Physiotherapy and bronchial mucus transport

    NARCIS (Netherlands)

    Schans, Cornelis Peter van der

    1991-01-01

    The use of physiotherapeutic techniques may increase mucus transport in patients with airways disease including COPD, asthma, cystic fibrosis and primary ciliary dyskinesia. The most effective parts of the treatment are probably forced expirations with open glottis and coughing. However, in patients

  6. Production of human intestinal trefoil factor in Pichia pastoris

    Institute of Scientific and Technical Information of China (English)

    SUN Yong; PENG Xi; Lü Shang-jun; ZHANG Yong; WANG Shi-liang

    2006-01-01

    Objective:To construct a Pichia pastoris (P. Pastoris) expression vector of human intestinal trefoil factor (hITF) and study its expression and purification procedures. Methods:hITF gene encoding mature peptide was modified with a polyhistidine tag sequence at the N-terminal, and then inserted into the P. Pastoris expression vector pGAPZαA at the ownstream of the α-mating factor signal. After gene sequencing, the recombinant pGAPZαA-hITF was transformed into the P. Pastoris strain X-33 with lithium chloride. rhITF was induced to constitutively express in shake flask, and then analyzed with Tricine SDS-PAGE and Western blotting. The obtained rhITF was isolated from the cultured supernatants y ammonium sulfate precipitation, Ni-NTA affinity chromatography, and ultrafiltration. Results:The correctness and integrity of rhITF were identified by restriction digestion and gene sequencing. rhITF was successfully expressed to 50 mg/L as a secretive protein. After purification, the purity was above 95%.Tricine SDS-PAGE and Western-blot analysis howed that rhITF presented as a single band with a molecular weight of 10 kDa, a little larger than 7 879 Da as assayed by mass spectrometry analysis. Conclusion:hITF P. Pastoris expression vector is successfully constructed and rhITF is expressed in P. Pastoris at commercially relevant level. This research lays foundation for the further functional tudying of hITF.

  7. Clinical features of human intestinal capillariasis in Taiwan

    Institute of Scientific and Technical Information of China (English)

    Ming-Jong Bair; Kao-Pin Hwang; Tsang-En Wang; Tai-Cherng Liou; Shee-Chan Lin; Chin-Roa Kao; Tao-Yeuan Wang; Kwok-Kuen Pang

    2004-01-01

    Human intestinal capillariasis is a rare parasitosis that was first recognized in the Philippines in the 1960 s. Parasitosis is a life threatening disease and has been reported from Thailand, Japan, South of Taiwan (Kaoh-Siung), Korea,Tran, Egypt, Italy and Spain. Its clinical symptoms are characterized by chronic diarrhea, abdominal pain,borborygmus, marked weight loss, protein and electrolyte loss and cachexia. Capillariasis may be fatal if early treatment is not given. We reported 14 cases living in rural areas of Taiwan. Three cases had histories of travelling to Thailand. They might have been infected in Thailand while stayed there. Two cases had the diet of raw freshwater fish before. Three cases received emergency laparotomy due to peritonitis and two cases were found of enteritis cystica profunda. According to the route of transmission,freshwater and brackish-water fish may act as the intermediate host of the parasite. The most simple and convenient method of diagnosing capillariasis is stool examination. Two cases were diagnosed by histology.Mebendazole or albendezole 200 mg orally twice a day for 20-30 d is the treatment of choice. All the patients were cured, and relapses were not observed within 12 mo.

  8. Diclofenac toxicity in human intestine ex vivo is not related to the formation of intestinal metabolites

    NARCIS (Netherlands)

    Niu, Xiaoyu; de Graaf, Inge A. M.; Langelaar-Makkinje, Miriam; Horvatovich, Peter; Groothuis, Geny M. M.

    2015-01-01

    The use of diclofenac (DCF), a nonsteroidal anti-inflammatory drug, is associated with a high prevalence of gastrointestinal side effects. In vivo studies in rodents suggested that reactive metabolites of DCF produced by the liver or the intestine might be responsible for this toxicity. In the prese

  9. Diclofenac toxicity in human intestine ex vivo is not related to the formation of intestinal metabolites

    NARCIS (Netherlands)

    Niu, Xiaoyu; de Graaf, Inge A. M.; Langelaar-Makkinje, Miriam; Horvatovich, Peter; Groothuis, Geny M. M.

    2015-01-01

    The use of diclofenac (DCF), a nonsteroidal anti-inflammatory drug, is associated with a high prevalence of gastrointestinal side effects. In vivo studies in rodents suggested that reactive metabolites of DCF produced by the liver or the intestine might be responsible for this toxicity. In the prese

  10. Role of Intestinal Microbiota in Ulcerative Colitis – Effects of Novel Carbohydrate Preparations

    DEFF Research Database (Denmark)

    Vigsnæs, Louise Kristine

    2011-01-01

    in a study of this thesis to elucidate, if the adhesion capacity is different depending on disease state. For this purpose, an in vitro dynamic gut model was used. Several bacterial taxa from both lumen and mucus were quantified using qPCR. The results revealed that the bacterial community of the mucus......, which could affect colonic health. In the experimental part of this thesis, the fecal microbiota derived from UC patients in either remission or with active disease and healthy subjects was quantified using quantitative Real‐Time PCR (qPCR) to examine the microbiota composition. The results demonstrated...... composition in remission either resembled the composition in healthy or in relapse, demonstrating that the microbiota in remission is unstable. The mucus layer lining the epithelium of the intestinal tract is important for the protection of the epithelium in humans. The commensal bacteria that colonize...

  11. Can probiotics modulate human disease by impacting intestinal barrier function?

    NARCIS (Netherlands)

    Bron, Peter A.; Kleerebezem, Michiel; Brummer, Robert Jan; Cani, Patrice D.; Mercenier, Annick; MacDonald, Thomas T.; Garcia-Ródenas, Clara L.; Wells, Jerry M.

    2017-01-01

    Intestinal barrier integrity is a prerequisite for homeostasis of mucosal function, which is balanced to maximise absorptive capacity, while maintaining efficient defensive reactions against chemical and microbial challenges. Evidence is mounting that disruption of epithelial barrier integrity is

  12. Metabolism of puerarin and daidzin by human intestinal bacteria and their relation to in vitro cytotoxicity.

    Science.gov (United States)

    Kim, D H; Yu, K U; Bae, E A; Han, M J

    1998-06-01

    When puerarin or daidzin were incubated for 24 h with human intestinal bacteria, two metabolites, daidzein and calycosin, were produced from them, respectively. The metabolic time course of puerarin was as follows: at an early time, puerarin was converted to daidzin, and then calycosin. The metabolic time course of daidzin by human intestinal bacteria was also similar to that of puerarin. The in vitro cytotoxicities of these metabolites, calycosin and daidzein, were superior to those of puerarin and daidzein.

  13. Mucosal biofilm communities in the human intestinal tract.

    Science.gov (United States)

    Macfarlane, Sandra; Bahrami, Bahram; Macfarlane, George T

    2011-01-01

    Complex and highly variable site-dependent bacterial ecosystems exist throughout the length of the human gastrointestinal tract. Until relatively recently, the majority of our information on intestinal microbiotas has come from studies on feces, or from aspirates taken from the upper gut. However, there is evidence showing that mucosal bacteria growing in biofilms on surfaces lining the gut differ from luminal populations, and that due to their proximity to the epithelial surface, these organisms may be important in modulating the host's immune system and contributing to some chronic inflammatory diseases. Over the past decade, increasing interest in mucosal bacteria, coupled with advances in molecular approaches for assessing microbial diversity, has begun to provide some insight into the complexity of these mucosa-associated communities. In gastrointestinal conditions such as inflammatory bowel diseases (ulcerative colitis, Crohn's disease), it has been shown that a dysbiosis exists in microbial community structure, and that there is a reduction in putatively protective mucosal organisms such as bifidobacteria. Therefore, manipulation of mucosal communities may be beneficial in restoring normal functionality in the gut, thereby improving the immune status and general health of the host. Biofilm structure and function has been studied intensively in the oral cavity, and as a consequence, mucosal communities in the mouth will not be covered in this chapter. This review addresses our current knowledge of mucosal populations in the gastrointestinal tract, changes that can occur in community structure in disease, and therapeutic modulation of biofilm composition by antibiotics, prebiotics, and probiotics. Copyright © 2011 Elsevier Inc. All rights reserved.

  14. Vasoactive intestinal peptide (VIP) inhibits human renal cell carcinoma proliferation.

    Science.gov (United States)

    Vacas, Eva; Fernández-Martínez, Ana B; Bajo, Ana M; Sánchez-Chapado, Manuel; Schally, Andrew V; Prieto, Juan C; Carmena, María J

    2012-10-01

    Clear renal cell carcinoma (cRCC) is an aggressive and fatal neoplasm. The present work was undertaken to investigate the antiproliferative potential of vasoactive intestinal peptide (VIP) exposure on non-tumoral (HK2) and tumoral (A498, cRCC) human proximal tubular epithelial cell lines. Reverse transcription and semiquantitative PCR was used at the VIP mRNA level whereas enzyme immunoanalysis was performed at the protein level. Both renal cell lines expressed VIP as well as VIP/pituitary adenylate cyclase-activating peptide (VPAC) receptors whereas only HK2 cells expressed formyl peptide receptor-like 1 (FPRL-1). Receptors were functional, as shown by VIP stimulation of adenylyl cyclase activity. Treatment with 0.1μM VIP (24h) inhibited proliferation of A498 but not HK2 cells as based on a reduction in the incorporation of [(3)H]-thymidine and BrdU (5'-Br-2'-deoxyuridine), PCNA (proliferating-cell nuclear antigen) expression and STAT3 (signal transducer and activator of transcription 3) expression and activation. VPAC(1)-receptor participation was established using JV-1-53 antagonist and siRNA transfection. Growth-inhibitory response to VIP was related to the cyclic adenosine monophosphate (cAMP)/exchange protein directly activated by cAMP (EPAC)/phosphoinositide 3-kinase (PI3-K) signaling systems as shown by studies on adenylate cyclase stimulation, and using the EPAC-specific compound 8CPT-2Me-cAMP and specific kinase inhibitors such as H89, wortmannin and PD98059. The efficacy of VIP on the prevention of tumor progression was confirmed in vivo using xenografted athymic mouse. These actions support a potential role of this peptide and its agonists in new therapies for cRCC.

  15. Transformation of trollioside and isoquercetin by human intestinal flora in vitro.

    Science.gov (United States)

    Yuan, Ming; Shi, Duo-Zhi; Wang, Teng-Yu; Zheng, Shi-Qi; Liu, Li-Jia; Sun, Zhen-Xiao; Wang, Ru-Feng; Ding, Yi

    2016-03-01

    The present study was designed to determine the intestinal bacterial metabolites of trollioside and isoquercetin and their antibacterial activities. A systematic in vitro biotransformation investigation on trollioside and isoquercetin, including metabolite identification, metabolic pathway deduction, and time course, was accomplished using a human intestinal bacterial model. The metabolites were analyzed and identified by HPLC and HPLC-MS. The antibacterial activities of trollioside, isoquercetin, and their metabolites were evaluated using the broth microdilution method with berberine as a positive control, and their potency was measured as minimal inhibitory concentration (MIC). Our results indicated that trollioside and isoquercetin were metabolized by human intestinal flora through O-deglycosylation, yielding aglycones proglobeflowery acid and quercetin, respectively The antibacterial activities of both metabolites were more potent than that of their parent compounds. In conclusion, trollioside and isoquercetin are totally and rapidly transformed by human intestinal bacteria in vitro and the transformation favors the improvement of the antibacterial activities of the parent compounds.

  16. SOX9 is expressed in normal stomach, intestinal metaplasia, and gastric carcinoma in humans.

    Science.gov (United States)

    Sashikawa Kimura, Miho; Mutoh, Hiroyuki; Sugano, Kentaro

    2011-11-01

    SOX9 is a marker for stem cells in the intestine and overexpression of SOX9 is found in some types of cancer. However, the expression of SOX9 in normal stomach, precancerous intestinal metaplasia, and gastric carcinoma has not yet been clarified. This study aimed to investigate SOX9 expression in the corpus and pyloric regions of the normal human stomach, premalignant intestinal metaplasia, and gastric carcinoma by using immunohistochemistry. We evaluated SOX9 expression in 46 clinical samples (early gastric well-differentiated adenocarcinoma including surrounding intestinal metaplasia) resected under esophagogastroduodenoscopy. A small amount of SOX9 was expressed in the neck/isthmus of the corpus region and SOX9 expression was predominantly restricted to the neck/isthmus of the pyloric region in normal human stomach. In the intestinal metaplastic mucosa, SOX9- and PCNA-positive cells were located at the base of the intestinal metaplastic mucosa. Almost all of the gastric carcinoma cells expressed SOX9. SOX9 is expressed in intestinal metaplasia and gastric carcinoma in humans.

  17. Differentiation-dependent activation of the human intestinal alkaline phosphatase promoter by HNF-4 in intestinal cells

    DEFF Research Database (Denmark)

    Olsen, Line; Bressendorff, Simon; Troelsen, Jesper T

    2005-01-01

    of the enterocytes, we have conducted a computer-assisted cis-element search of the proximal human ALPI promoter sequence. A putative recognition site for the transcription factor hepatocyte nuclear factor (HNF)-4 was predicted at the positions from -94 to -82 in relation to the translational start site. The ability......The intestinal alkaline phosphatase gene (ALPI) encodes a digestive brush-border enzyme, which is highly upregulated during small intestinal epithelial cell differentiation. To identify new putative promoter motifs responsible for the regulation of ALPI expression during differentiation...... of HNF-4alpha to stimulate the expression from the ALPI promoter was investigated in the nonintestinal Hela cell line. Cotransfection with an HNF-4alpha expression vector demonstrated a direct activation of the ALPI promoter through this -94 to -82 element. EMSA showed that HNF-4alpha from nuclear...

  18. Human intestine luminal ACE2 and amino acid transporter expression increased by ACE-inhibitors.

    Science.gov (United States)

    Vuille-dit-Bille, Raphael N; Camargo, Simone M; Emmenegger, Luca; Sasse, Tom; Kummer, Eva; Jando, Julia; Hamie, Qeumars M; Meier, Chantal F; Hunziker, Schirin; Forras-Kaufmann, Zsofia; Kuyumcu, Sena; Fox, Mark; Schwizer, Werner; Fried, Michael; Lindenmeyer, Maja; Götze, Oliver; Verrey, François

    2015-04-01

    Sodium-dependent neutral amino acid transporter B(0)AT1 (SLC6A19) and imino acid (proline) transporter SIT1 (SLC6A20) are expressed at the luminal membrane of small intestine enterocytes and proximal tubule kidney cells where they exert key functions for amino acid (re)absorption as documented by their role in Hartnup disorder and iminoglycinuria, respectively. Expression of B(0)AT1 was shown in rodent intestine to depend on the presence of the carboxypeptidase angiotensin-converting enzyme 2 (ACE2). This enzyme belongs to the renin-angiotensin system and its expression is induced by treatment with ACE-inhibitors (ACEIs) or angiotensin II AT1 receptor blockers (ARBs) in many rodent tissues. We show here in the Xenopus laevis oocyte expression system that human ACE2 also functionally interacts with SIT1. To investigate in human intestine the potential effect of ACEIs or ARBs on ACE2, we analysed intestinal biopsies taken during routine gastroduodenoscopy and ileocolonoscopy from 46 patients of which 9 were under ACEI and 13 ARB treatment. Analysis of transcript expression by real-time PCR and of proteins by immunofluorescence showed a co-localization of SIT1 and B(0)AT1 with ACE2 in the brush-border membrane of human small intestine enterocytes and a distinct axial expression pattern of the tested gene products along the intestine. Patients treated with ACEIs displayed in comparison with untreated controls increased intestinal mRNA levels of ACE2, peptide transporter PEPT1 (SLC15A1) and AA transporters B(0)AT1 and PAT1 (SLC36A1). This study unravels in human intestine the localization and distribution of intestinal transporters involved in amino acid absorption and suggests that ACEIs impact on their expression.

  19. QSAR Study and VolSurf Characterization of Human Intestinal Absorption of Druge

    Institute of Scientific and Technical Information of China (English)

    胡桂香; 商志才; 等

    2003-01-01

    The prediction of human intestinal absorption is a major goal in the design,optimization,and selection of candidates for the develoment of oral drugs.In this study,a computerized method(VolSurf with GRID) was used as a novel tool for predicting human intestinal absorption of test compound,and for determining the critical molecular properties needed for human intestinal absorption.The tested molecules consisted of 20 diverse drug-like compounds.Partial least squares(PLS) discriminant analysis was used to correlate the experimental data with the theoretical molecular properties of human intestinal absorption.A good correlation(r2=0.95,q2=0.86) between the molecular modeling results and the experimental data demonstrated that human intestinal absorption could be predicted from the three-dimensional(3D) molecular structure of a compound .Favorable structureal properties identified for the potent intestinal absorption of drugs included strong imbalance between the center of mass of a molecule and the barycentre of its hydrophilic and hydrophobic regions and a definitive hydrophobic region as well as less hydrogen bonding donors and acceptors in the molecule.

  20. Comparative proteomic analysis of cell lines and scrapings of the human intestinal epithelium

    Directory of Open Access Journals (Sweden)

    Renes Johan

    2007-04-01

    Full Text Available Abstract Background In vitro models are indispensable study objects in the fields of cell and molecular biology, with advantages such as accessibility, homogeneity of the cell population, reproducibility, and growth rate. The Caco-2 cell line, originating from a colon carcinoma, is a widely used in vitro model for small intestinal epithelium. Cancer cells have an altered metabolism, making it difficult to infer their representativity for the tissue from which they are derived. This study was designed to compare the protein expression pattern of Caco-2 cells with the patterns of intestinal epithelial cells from human small and large intestine. HT-29 intestinal cells, Hep G2 liver cells and TE 671 muscle cells were included too, the latter two as negative controls. Results Two-dimensional gel electrophoresis was performed on each tissue and cell line protein sample. Principal component and cluster analysis revealed that global expression of intestinal epithelial scrapings differed from that of intestinal epithelial cell lines. Since all cultured cell lines clustered together, this finding was ascribed to an adaptation of cells to culture conditions and their tumor origin, and responsible proteins were identified by mass spectrometry. When investigating the profiles of Caco-2 cells and small intestinal cells in detail, a considerable overlap was observed. Conclusion Numerous proteins showed a similar expression in Caco-2 cells, HT-29 cells, and both the intestinal scrapings, of which some appear to be characteristic to human intestinal epithelium in vivo. In addition, several biologically significant proteins are expressed at comparable levels in Caco-2 cells and small intestinal scrapings, indicating the usability of this in vitro model. Caco-2 cells, however, appear to over-express as well as under-express certain proteins, which needs to be considered by scientists using this cell line. Hence, care should be taken to prevent misinterpretation of

  1. Estradiol increases mucus synthesis in bronchial epithelial cells.

    Directory of Open Access Journals (Sweden)

    Anthony Tam

    Full Text Available Airway epithelial mucus hypersecretion and mucus plugging are prominent pathologic features of chronic inflammatory conditions of the airway (e.g. asthma and cystic fibrosis and in most of these conditions, women have worse prognosis compared with male patients. We thus investigated the effects of estradiol on mucus expression in primary normal human bronchial epithelial cells from female donors grown at an air liquid interface (ALI. Treatment with estradiol in physiological ranges for 2 weeks caused a concentration-dependent increase in the number of PAS-positive cells (confirmed to be goblet cells by MUC5AC immunostaining in ALI cultures, and this action was attenuated by estrogen receptor beta (ER-β antagonist. Protein microarray data showed that nuclear factor of activated T-cell (NFAT in the nuclear fraction of NHBE cells was increased with estradiol treatment. Estradiol increased NFATc1 mRNA and protein in ALI cultures. In a human airway epithelial (1HAE0 cell line, NFATc1 was required for the regulation of MUC5AC mRNA and protein. Estradiol also induced post-translational modification of mucins by increasing total fucose residues and fucosyltransferase (FUT-4, -5, -6 mRNA expression. Together, these data indicate a novel mechanism by which estradiol increases mucus synthesis in the human bronchial epithelium.

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

    Science.gov (United States)

    Mabbott, Neil A

    2015-10-01

    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 in elderly humans, the molecular mechanisms which cause this dramatic functional decline are poorly understood. Our current understanding of the effects of aging on the physical and immunological properties of the intestinal epithelial barrier is also very limited. In this issue of Clinical Science, Man et al. provide further insight into the effects of aging on small intestinal barrier function in humans and the influence that gut luminal micro-organisms may have on it. Using human terminal ileal biopsy tissues they show that intestinal permeability to solutes, but not macromolecules, was significantly increased in the intestines of elderly humans. This was accompanied by elevated expression of the pro-inflammatory cytokine interleukin (IL)-6 which appeared to modulate claudin-2 expression and solute permeability in the epithelium. Conversely, IL-8 synthesis in response to flagellin stimulation was reduced in intestines of the elderly subjects, but was not associated with effects on Toll-like receptor 5 (TLR5) expression. These data provide an important advance in our understanding on the effects of aging on intestinal permeability and innate mucosal immune responsiveness in elderly humans.

  3. Rice Bran and Probiotics Alter the Porcine Large Intestine and Serum Metabolomes for Protection against Human Rotavirus Diarrhea

    Directory of Open Access Journals (Sweden)

    Elizabeth P. Ryan

    2017-04-01

    Full Text Available Human rotavirus (HRV is a leading cause of severe childhood diarrhea, and there is limited vaccine efficacy in the developing world. Neonatal gnotobiotic pigs consuming a prophylactic synbiotic combination of probiotics and rice bran (Pro+RB did not exhibit HRV diarrhea after challenge. Multiple immune, gut barrier protective, and anti-diarrheal mechanisms contributed to the prophylactic efficacy of Pro+RB when compared to probiotics (Pro alone. In order to understand the molecular signature associated with diarrheal protection by Pro+RB, a global non-targeted metabolomics approach was applied to investigate the large intestinal contents and serum of neonatal gnotobiotic pigs. The ultra-high performance liquid chromatography-tandem mass spectrometry platform revealed significantly different metabolites (293 in LIC and 84 in serum in the pigs fed Pro+RB compared to Pro, and many of these metabolites were lipids and amino acid/peptides. Lipid metabolites included 2-oleoylglycerol (increased 293.40-fold in LIC of Pro+RB, p = 3.04E-10, which can modulate gastric emptying, andhyodeoxycholate (decreased 0.054-fold in the LIC of Pro+RB, p = 0.0040 that can increase colonic mucus production to improve intestinal barrier function. Amino acid metabolites included cysteine (decreased 0.40-fold in LIC, p = 0.033, and 0.62-fold in serum, p = 0.014 of Pro+RB, which has been found to reduce inflammation, lower oxidative stress and modulate mucosal immunity, and histamine (decreased 0.18-fold in LIC, p = 0.00030, of Pro+RB and 1.57-fold in serum, p = 0.043, which modulates local and systemic inflammatory responses as well as influences the enteric nervous system. Alterations to entire LIC and serum metabolic pathways further contributed to the anti-diarrheal and anti-viral activities of Pro+RB such as sphingolipid, mono/diacylglycerol, fatty acid, secondary bile acid, and polyamine metabolism. Sphingolipid and long chain fatty acid profiles influenced the

  4. Development of microfluidic cell culture devices towards an in vitro human intestinal barrier model

    DEFF Research Database (Denmark)

    Tan, Hsih-Yin

    folds that closely resembled the intestinal villi and formation of a tight barrier. Furthermore, the microelectrodes embedded in the microchip also allow real-time monitoring of the barrier integrity by means of measuring the trans-epithelial electrical resistance. Demonstrations of transport studies...... using different compounds on the in vitro human intestinal model in the microfluidic device showed comparable results with static cultures. In addition, a normal commensal intestinal bacteria, Escherichia coli (E. coli) was successfully co-cultured on the luminal surface of the cultured epithelium...

  5. Isolation and Identification of Intestinal CYP3A Inhibitors from Cranberry (Vaccinium macrocarpon) using Human Intestinal Microsomes

    Science.gov (United States)

    Kim, Eunkyung; Sy-Cordero, Arlene; Graf, Tyler N.; Brantley, Scott J.; Paine, Mary F.; Oberlies, Nicholas H.

    2010-01-01

    Cranberry juice is used routinely, especially among women and the elderly, to prevent and treat urinary tract infections. These individuals are likely to be taking medications concomitantly with cranberry juice, leading to concern about potential drug-dietary substance interactions, particularly in the intestine, which, along with the liver, is rich in expression of the prominent drug metabolizing enzyme, cytochrome P450 3A (CYP3A). Using a systematic in vitro-in vivo approach, a cranberry juice product was identified recently that elicited a pharmacokinetic interaction with the CYP3A probe substrate midazolam in 16 healthy volunteers. Relative to water, a cranberry juice inhibited intestinal first-pass midazolam metabolism. In vitro studies were initiated to identify potential enteric CYP3A inhibitors from cranberry via a bioactivity-directed fractionation approach involving dried whole cranberry [Vaccinium macrocarpon Ait. (Ericaceae)], midazolam, and human intestinal microsomes (HIM). Three triterpenes (maslinic acid, corosolic acid, and ursolic acid) were isolated. The inhibitory potency (IC50) of maslinic acid, corosolic acid, and ursolic acid was 7.4, 8.8, and triterpenes may have contributed to the midazolam-cranberry juice interaction observed in the clinical study. PMID:20717876

  6. Characterization of two cysteine proteases secreted by Blastocystis ST7, a human intestinal parasite.

    Science.gov (United States)

    Wawrzyniak, Ivan; Texier, Catherine; Poirier, Philippe; Viscogliosi, Eric; Tan, Kevin S W; Delbac, Frédéric; El Alaoui, Hicham

    2012-09-01

    Blastocystis spp. are unicellular anaerobic intestinal parasites of both humans and animals and the most prevalent ones found in human stool samples. Their association with various gastrointestinal disorders raises the questions of its pathogenicity and of the molecular mechanisms involved. Since secreted proteases are well-known to be implicated in intestinal parasite virulence, we intended to determine whether Blastocystis spp. possess such pathogenic factors. In silico analysis of the Blastocystis subtype 7 (ST7) genome sequence highlighted 22 genes coding proteases which were predicted to be secreted. We characterized the proteolytic activities in the secretory products of Blastocystis ST7 using specific protease inhibitors. Two cysteine proteases, a cathepsin B and a legumain, were identified in the parasite culture supernatant by gelatin zymographic SDS-PAGE gel and MS/MS analysis. These proteases might act on intestinal cells and disturb gut function. This work provides serious molecular candidates to link Blastocystis spp. and intestinal disorders.

  7. Molecular characterisation of non-absorptive and absorptive enterocytes in human small intestine

    DEFF Research Database (Denmark)

    Gassler, N; Newrzella, D; Böhm, C;

    2006-01-01

    BACKGROUND AND AIMS: Perturbation of differentiation of the crypt-villus axis of the human small intestine is associated with several intestinal disorders of clinical importance. At present, differentiation of small intestinal enterocytes in the crypt-villus axis is not well characterised. SUBJECTS...... genes, and vesicle/transport related genes was found. CONCLUSION: Two types of enterocytes were dissected at the molecular level, the non-absorptive enterocyte located in the upper part of crypts and the absorptive enterocyte found in the middle of villi. These data improve our knowledge about...... the physiology of the crypt-villus architecture in human small intestine and provide new insights into pathophysiological phenomena, such as villus atrophy, which is clinically important....

  8. Impact of Diet on Human Intestinal Microbiota and Health

    NARCIS (Netherlands)

    Salonen, A.; Vos, de W.M.

    2014-01-01

    Our intestinal microbiota is involved in the breakdown and bioconversion of dietary and host components that are not degraded and taken up by our own digestive system. The end products generated by our microbiota fuel our enterocytes and support growth but also have signaling functions that generate

  9. Intestinal immune response to human Cryptosporidium sp. infection

    Science.gov (United States)

    2008-01-01

    intestinal tissues from AIDS patients with cryptosporidiosis, we did not detect CXCL-8 (90). Finally, CXCL-8 attracts mainly granu - locytes. However, in...cryptosporidiosis but not after reconstitution of immunity. Infect. Immun. 75:481–487. 91. Weinstock, J. V., A. Blum, J. Walder, and R. Walder. 1988. Eosinophils

  10. Impact of Diet on Human Intestinal Microbiota and Health

    NARCIS (Netherlands)

    Salonen, A.; Vos, de W.M.

    2014-01-01

    Our intestinal microbiota is involved in the breakdown and bioconversion of dietary and host components that are not degraded and taken up by our own digestive system. The end products generated by our microbiota fuel our enterocytes and support growth but also have signaling functions that generate

  11. Host-Microbe Interactions in the Neonatal Intestine: Role of Human Milk Oligosaccharides123

    OpenAIRE

    Donovan, Sharon M.; Wang, Mei; LI, MIN; Friedberg, Iddo; Schwartz, Scott L.; Robert S Chapkin

    2012-01-01

    The infant intestinal microbiota is shaped by genetics and environment, including the route of delivery and early dietary intake. Data from germ-free rodents and piglets support a critical role for the microbiota in regulating gastrointestinal and immune development. Human milk oligosaccharides (HMO) both directly and indirectly influence intestinal development by regulating cell proliferation, acting as prebiotics for beneficial bacteria and modulating immune development. We have shown that ...

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

    Directory of Open Access Journals (Sweden)

    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

  13. Reducing mucus production after urinary reconstruction: a prospective randomized trial.

    Science.gov (United States)

    N'Dow, J; Robson, C N; Matthews, J N; Neal, D E; Pearson, J P

    2001-05-01

    After transposition into the urinary tract, intestinal segments continue to produce mucus. We determine the effectiveness of muco-regulatory drugs, including N-acetylcysteine, aspirin and ranitidine, in reducing mucus secretion and urine viscosity in patients with transposed segments. Our trial was a prospective randomized, double-blind placebo controlled crossover study involving 12 patients who underwent ileal conduit and 31 who underwent bladder reconstruction. Each treatment lasted 3 weeks with a 2-week washout. Pretreatment and posttreatment 24-hour urine samples were analyzed for mucin and viscosity after papain digestion, sodium dodecyl sulfate-polyacrylamide gel electrophoresis and periodic acid-Schiff assay. A disease specific questionnaire and SF-36 quality of life survey were completed. According to the questionnaire, mucus production did not decrease with time in 67% of patients. Mucin comprised 3% of the total nondialyzable material in urine (65 mg./24-hour for ileal conduit and 60 mg./24-hour for bladder reconstruction). Analysis of questionnaires and laboratory results failed to demonstrate any benefit of taking muco-regulatory agents compared with placebo. The use of N-acetylcysteine, aspirin and ranitidine did not result in a reduction in mucin production, urine viscosity or improvement in quality of life.

  14. Assessing DNA methylation in the developing human intestinal epithelium: potential link to inflammatory bowel disease.

    Science.gov (United States)

    Kraiczy, J; Nayak, K; Ross, A; Raine, T; Mak, T N; Gasparetto, M; Cario, E; Rakyan, V; Heuschkel, R; Zilbauer, M

    2016-05-01

    DNA methylation is one of the major epigenetic mechanisms implicated in regulating cellular development and cell-type-specific gene expression. Here we performed simultaneous genome-wide DNA methylation and gene expression analysis on purified intestinal epithelial cells derived from human fetal gut, healthy pediatric biopsies, and children newly diagnosed with inflammatory bowel disease (IBD). Results were validated using pyrosequencing, real-time PCR, and immunostaining. The functional impact of DNA methylation changes on gene expression was assessed by employing in-vitro assays in intestinal cell lines. DNA methylation analyses allowed identification of 214 genes for which expression is regulated via DNA methylation, i.e. regulatory differentially methylated regions (rDMRs). Pathway and functional analysis of rDMRs suggested a critical role for DNA methylation in regulating gene expression and functional development of the human intestinal epithelium. Moreover, analysis performed on intestinal epithelium of children newly diagnosed with IBD revealed alterations in DNA methylation within genomic loci, which were found to overlap significantly with those undergoing methylation changes during intestinal development. Our study provides novel insights into the physiological role of DNA methylation in regulating functional maturation of the human intestinal epithelium. Moreover, we provide data linking developmentally acquired alterations in the DNA methylation profile to changes seen in pediatric IBD.

  15. Accumulation of dietary and aqueous cadmium into the epidermal mucus of the discus fish Symphysodon sp

    Energy Technology Data Exchange (ETDEWEB)

    Maunder, Richard J., E-mail: richard.maunder@astrazeneca.com [School of Marine Science and Engineering, University of Plymouth, Drake Circus, Plymouth, PL4 8AA (United Kingdom); Buckley, Jonathan, E-mail: jonathan.buckley@plymouth.ac.uk [School of Marine Science and Engineering, University of Plymouth, Drake Circus, Plymouth, PL4 8AA (United Kingdom); Val, Adalberto L., E-mail: dalval@inpa.gov.br [Department of Ecology, Laboratory of Ecophysiology and Molecular Evolution, INPA, Manaus (Brazil); Sloman, Katherine A., E-mail: katherine.sloman@uws.ac.uk [School of Science, University of the West of Scotland, Paisley, PA1 2BE, Scotland (United Kingdom)

    2011-06-15

    The discus fish Symphysodon sp. is an Amazonian cichlid with a unusual form of parental care where fry obligately feed from parental mucus for the first few weeks of life. Here, we investigated the possible impact of environmental cadmium on this species, particularly with respect to mucus contamination. We exposed groups of fish to cadmium either through their food (400 mg kg{sup -1}) or through the water (3 {mu}g l{sup -1}) for 4 weeks, and measured tissue concentrations and ATPase activities at weekly intervals. Cadmium significantly accumulated in all tissues (except for muscle) after 7 days, and tissue concentrations increased until the end of the experiment. Significant alterations in ATPase activities of intestine and kidney were observed at day 7 and 14, but no alterations in gill ATPase activities occurred. The epidermal mucus showed a high accumulation of cadmium from both exposures, but particularly from the diet, indicating that dietary cadmium can be transferred from gut to mucus. Combining this data with approximations of fry bite volumes and bite frequencies, we constructed daily estimates of the cadmium that could potentially be consumed by newly hatched fry feeding on this mucus. These calculations suggest that feeding fry might consume up to 11 {mu}g g{sup -1} day{sup -1}, and hence indicate that this species' dependency on parental mucus feeding of fry could make them particularly susceptible to cadmium contamination of their native habitat.

  16. Antimicrobial and hemolytic activity of fish epidermal mucus Cynoglossus arel andArius caelatus

    Institute of Scientific and Technical Information of China (English)

    Subramanian Bragadeeswaran; Selvam Priyadharshini; Kolandhasamy Prabhu; Solomon Raj Sophia Rani

    2011-01-01

    Objective:To study the antimicrobial, hemolytic activity and immunomodulatory activity of fish epidermal mucus and their chemical constituents fromCynoglossus arel (C. arel) and Arius caelatus (A. caelatus). Mucus plays an important role in the prevention of colonization by parasites, bacteria and fungi.Methods: Epidermal mucus was obtained from two marine fishes, lyophilized and the chemical composition of epidermal mucus was analysed byFT-IR analysis. Thein vitro antimicrobial activity against human pathogens (fungi, gram positive and gram-negative bacteria) and also the hemolytic activity and immunomodulatory activity were determined.Results:Totally ten human pathogens were tested against the fish mucus. Out of the ten pathogens, five pathogens have proved to be sensitive to the mucus. Maximum zone of inhibition was observed againstVibrio cholera (V. cholera) (9 mm and2 mm in diameter), followed byStaphylococcus aureus (S. aureus) with a inhibition zone of (6 mm and3 mm),Streptococcus areus (S. areus) (5 mm and4 mm),Vibrio parahemolyticus (V. parahemolyticus) (4mm and5 mm) respectively.Conclusions: The present investigation has revealed that positive progresses in the fish mucus extracts against human pathogens and hemolytic activity. But further efforts are required for the purification and isolation of the active antimicrobial compounds in order to establish their possible applications.

  17. Human flora-associated (HFA) animals as a model for studying the role of intestinal flora in human health and disease.

    Science.gov (United States)

    Hirayama, Kazuhiro; Itoh, Kikuji

    2005-09-01

    Although the intestinal flora in animals plays an important role in health and disease, there is little direct information regarding the role of the human intestinal flora. By inoculating germfree animals with human faeces, the major components of the human flora can be transferred into the ex-germfree animals, i.e. human flora-associated (HFA) animals. HFA animals therefore provide a stable model for studying the ecosystem and metabolism of the human intestinal flora. Results with HFA animals suggest the role of the human intestinal flora is somewhat different from the role of the animal flora in conventional experimental animals. Studies using HFA animals, therefore, will provide much needed information on the precise role of the intestinal flora in relation to humans. HFA animals also can be used as models to investigate the interactions between the human intestinal flora, host factors, dietary manipulations, and therapeutics, such as probiotics, prebiotics, and antibiotics.

  18. High taxonomic level fingerprint of the human intestinal microbiota by Ligase Detection Reaction - Universal Array approach

    Directory of Open Access Journals (Sweden)

    Vitali Beatrice

    2010-04-01

    Full Text Available Abstract Background Affecting the core functional microbiome, peculiar high level taxonomic unbalances of the human intestinal microbiota have been recently associated with specific diseases, such as obesity, inflammatory bowel diseases, and intestinal inflammation. Results In order to specifically monitor microbiota unbalances that impact human physiology, here we develop and validate an original DNA-microarray (HTF-Microbi.Array for the high taxonomic level fingerprint of the human intestinal microbiota. Based on the Ligase Detection Reaction-Universal Array (LDR-UA approach, the HTF-Microbi.Array enables specific detection and approximate relative quantification of 16S rRNAs from 30 phylogenetically related groups of the human intestinal microbiota. The HTF-Microbi.Array was used in a pilot study of the faecal microbiota of eight young adults. Cluster analysis revealed the good reproducibility of the high level taxonomic microbiota fingerprint obtained for each of the subject. Conclusion The HTF-Microbi.Array is a fast and sensitive tool for the high taxonomic level fingerprint of the human intestinal microbiota in terms of presence/absence of the principal groups. Moreover, analysis of the relative fluorescence intensity for each probe pair of our LDR-UA platform can provide estimation of the relative abundance of the microbial target groups within each samples. Focusing the phylogenetic resolution at division, order and cluster levels, the HTF-Microbi.Array is blind with respect to the inter-individual variability at the species level.

  19. Expression, Distribution and Role of Aquaporin Water Channels in Human and Animal Stomach and Intestines.

    Science.gov (United States)

    Zhu, Cui; Chen, Zhuang; Jiang, Zongyong

    2016-08-29

    Stomach and intestines are involved in the secretion of gastrointestinal fluids and the absorption of nutrients and fluids, which ensure normal gut functions. Aquaporin water channels (AQPs) represent a major transcellular route for water transport in the gastrointestinal tract. Until now, at least 11 AQPs (AQP1-11) have been found to be present in the stomach, small and large intestines. These AQPs are distributed in different cell types in the stomach and intestines, including gastric epithelial cells, gastric glands cells, absorptive epithelial cells (enterocytes), goblet cells and Paneth cells. AQP1 is abundantly distributed in the endothelial cells of the gastrointestinal tract. AQP3 and AQP4 are mainly distributed in the basolateral membrane of epithelial cells in the stomach and intestines. AQP7, AQP8, AQP10 and AQP11 are distributed in the apical of enterocytes in the small and large intestines. Although AQP-null mice displayed almost no phenotypes in gastrointestinal tracts, the alterations of the expression and localization of these AQPs have been shown to be associated with the pathology of gastrointestinal disorders, which suggests that AQPs play important roles serving as potential therapeutic targets. Therefore, this review provides an overview of the expression, localization and distribution of AQPs in the stomach, small and large intestine of human and animals. Furthermore, this review emphasizes the potential roles of AQPs in the physiology and pathophysiology of stomach and intestines.

  20. Expression, Distribution and Role of Aquaporin Water Channels in Human and Animal Stomach and Intestines

    Directory of Open Access Journals (Sweden)

    Cui Zhu

    2016-08-01

    Full Text Available Stomach and intestines are involved in the secretion of gastrointestinal fluids and the absorption of nutrients and fluids, which ensure normal gut functions. Aquaporin water channels (AQPs represent a major transcellular route for water transport in the gastrointestinal tract. Until now, at least 11 AQPs (AQP1–11 have been found to be present in the stomach, small and large intestines. These AQPs are distributed in different cell types in the stomach and intestines, including gastric epithelial cells, gastric glands cells, absorptive epithelial cells (enterocytes, goblet cells and Paneth cells. AQP1 is abundantly distributed in the endothelial cells of the gastrointestinal tract. AQP3 and AQP4 are mainly distributed in the basolateral membrane of epithelial cells in the stomach and intestines. AQP7, AQP8, AQP10 and AQP11 are distributed in the apical of enterocytes in the small and large intestines. Although AQP-null mice displayed almost no phenotypes in gastrointestinal tracts, the alterations of the expression and localization of these AQPs have been shown to be associated with the pathology of gastrointestinal disorders, which suggests that AQPs play important roles serving as potential therapeutic targets. Therefore, this review provides an overview of the expression, localization and distribution of AQPs in the stomach, small and large intestine of human and animals. Furthermore, this review emphasizes the potential roles of AQPs in the physiology and pathophysiology of stomach and intestines.

  1. Intestinal microbiota in human health and disease: the impact of probiotics

    NARCIS (Netherlands)

    Gerritsen, J.; Smidt, H.; Rijkers, G.T.; Vos, de W.M.

    2011-01-01

    The complex communities of microorganisms that colonise the human gastrointestinal tract play an important role in human health. The development of culture-independent molecular techniques has provided new insights in the composition and diversity of the intestinal microbiota. Here, we summarise the

  2. Intestinal microbiota in human health and disease: the impact of probiotics

    NARCIS (Netherlands)

    Gerritsen, J.; Smidt, H.; Rijkers, G.T.; Vos, de W.M.

    2011-01-01

    The complex communities of microorganisms that colonise the human gastrointestinal tract play an important role in human health. The development of culture-independent molecular techniques has provided new insights in the composition and diversity of the intestinal microbiota. Here, we summarise the

  3. Analyzing the functionality of the human intestinal microbiota by stable isotope probing

    NARCIS (Netherlands)

    Kovatcheva, P.P.

    2010-01-01

    Key words: gut bacteria, dietary carbohydrates, digestion, RNA-SIP, TIM-2, HITChip, human trial The human gastro-intestinal (GI) tract comprises a series of complex and dynamic organs ranging from the stomach to the distal colon, which harbor immense microbial assemblages, with considerable diversi

  4. Circulating intestine-derived exosomal miR-328 in plasma, a possible biomarker for estimating BCRP function in the human intestines.

    Science.gov (United States)

    Gotanda, Keisuke; Hirota, Takeshi; Saito, Jumpei; Fukae, Masato; Egashira, Yu; Izumi, Noritomo; Deguchi, Mariko; Kimura, Miyuki; Matsuki, Shunji; Irie, Shin; Ieiri, Ichiro

    2016-08-30

    A variant in the breast cancer resistance protein (BCRP) gene, 421C> A is a useful biomarker for describing large inter-individual differences in the pharmacokinetics of sulfasalazine (SASP), a BCRP substrate. However, large intra-genotypic variability still exists in spite of the incorporation of this variant into the pharmacokinetics of SASP. Since miR-328 negatively regulates BCRP expression in human tissues, we hypothesized that exosomal miR-328 in plasma, which leaks from the intestines, is a possible biomarker for estimating BCRP activity in the human intestines. We established an immunoprecipitation-based quantitative method for circulating intestine-derived miR-328 in plasma using an anti-glycoprotein A33 antibody. A clinical study was conducted with an open-label, non-randomized, and single-arm design involving 33 healthy participants. Intestine-derived exosomal miR-328 levels positively correlated (P intestinal BCRP activity, resulting in the high AUC of SASP. Circulating intestine-derived exosomal miR-328 in plasma has potential as a possible biomarker for estimating BCRP function in the human intestines.

  5. Study of the Biotransformation of Tongmai Formula by Human Intestinal Flora and Its Intestinal Permeability across the Caco-2 Cell Monolayer

    Directory of Open Access Journals (Sweden)

    Shuai Wu

    2015-10-01

    Full Text Available Tongmai formula (TMF is a well-known Chinese medicinal preparation that contains isoflavones as its major bioactive constituents. As traditional Chinese medicines (TCMs are usually used by oral administration, their fate inside the intestinal lumen, including their biotransformation by human intestinal flora (HIF and intestinal absorption deserves study. In this work TMF extract was incubated with human intestinal bacteria under anaerobic conditions and the changes in the twelve main constituents of TMF were then investigated. Their intestinal permeabilities, i.e., the transport capability across the intestinal brush border were investigated with a human colon carcinoma cell line (Caco­2 cell monolayer model to predict the absorption mechanism. Meanwhile, rapid HPLC-DAD methods were established for the assay. According to the biotransformation curves of the twelve constituents and the permeability coefficients, the intestinal absorption capacity of the typical compounds was elevated from the levels of 10−7 cm/s to 10−5 cm/s from those of the original compounds in TMF. Among them the main isoflavone glycosides puerarin (4, mirificin (6 and daidzin (7 were transformed into the same aglycone, daidzein (10. Therefore it was predicted that the aglycone compounds might be the real active ingredients in TMF. The models used can represent a novel path for the TCM studies.

  6. Study of the Biotransformation of Tongmai Formula by Human Intestinal Flora and Its Intestinal Permeability across the Caco-2 Cell Monolayer.

    Science.gov (United States)

    Wu, Shuai; Xu, Wei; Wang, Fu-Rong; Yang, Xiu-Wei

    2015-10-15

    Tongmai formula (TMF) is a well-known Chinese medicinal preparation that contains isoflavones as its major bioactive constituents. As traditional Chinese medicines (TCMs) are usually used by oral administration, their fate inside the intestinal lumen, including their biotransformation by human intestinal flora (HIF) and intestinal absorption deserves study. In this work TMF extract was incubated with human intestinal bacteria under anaerobic conditions and the changes in the twelve main constituents of TMF were then investigated. Their intestinal permeabilities, i.e., the transport capability across the intestinal brush border were investigated with a human colon carcinoma cell line (Caco-2) cell monolayer model to predict the absorption mechanism. Meanwhile, rapid HPLC-DAD methods were established for the assay. According to the biotransformation curves of the twelve constituents and the permeability coefficients, the intestinal absorption capacity of the typical compounds was elevated from the levels of 10(-7) cm/s to 10(-5) cm/s from those of the original compounds in TMF. Among them the main isoflavone glycosides puerarin (4), mirificin (6) and daidzin (7) were transformed into the same aglycone, daidzein (10). Therefore it was predicted that the aglycone compounds might be the real active ingredients in TMF. The models used can represent a novel path for the TCM studies.

  7. Transgenic milk containing recombinant human lactoferrin modulates the intestinal flora in piglets.

    Science.gov (United States)

    Hu, Wenping; Zhao, Jie; Wang, Jianwu; Yu, Tian; Wang, Jing; Li, Ning

    2012-06-01

    Lactoferrin (LF) is a beneficial multifunctional protein in milk. The objective of this study was to determine whether bovine transgenic milk containing recombinant human lactoferrin (rhLF) can modulate intestinal flora in the neonatal pig as an animal model for the human infant. We fed 7-day-old piglets (i) ordinary whole milk (OM), (ii) a 1:1 mixture of OM and rhLF milk (MM), or (iii) rhLF milk (LFM). LFM provided better average daily mass gain than OM (P = 0.007). PCR-denaturing gradient gel electrophoresis and 16S rDNA sequencing analysis revealed that the LFM piglets exhibited more diversity of the intestinal flora than the OM group. Except for the colon in the LFM group, an increasing trend in microbial diversity occurred from the duodenum to the colon. Fecal flora was not different across different ages or different treatment groups, but a cluster analysis showed that the fecal flora of OM- and MM-fed piglets had a higher degree of similarity than that of LFM-fed piglets. Based on culture-based bacterial counts of intestinal content samples, concentrations of Salmonella spp. in the colon and of Escherichia coli throughout the intestine were reduced with LFM (P intestine were also increased with LFM (P ≤ 0.01). We suggest that rhLF can modulate the intestinal flora in piglets.

  8. The human milk oligosaccharide 2'-fucosyllactose augments the adaptive response to extensive intestinal.

    Science.gov (United States)

    Mezoff, Ethan A; Hawkins, Jennifer A; Ollberding, Nicholas J; Karns, Rebekah; Morrow, Ardythe L; Helmrath, Michael A

    2016-03-15

    Intestinal resection resulting in short bowel syndrome (SBS) carries a heavy burden of long-term morbidity, mortality, and cost of care, which can be attenuated with strategies that improve intestinal adaptation. SBS infants fed human milk, compared with formula, have more rapid intestinal adaptation. We tested the hypothesis that the major noncaloric human milk oligosaccharide 2'-fucosyllactose (2'-FL) contributes to the adaptive response after intestinal resection. Using a previously described murine model of intestinal adaptation, we demonstrated increased weight gain from 21 to 56 days (P < 0.001) and crypt depth at 56 days (P < 0.0095) with 2'-FL supplementation after ileocecal resection. Furthermore, 2'-FL increased small bowel luminal content microbial alpha diversity following resection (P < 0.005) and stimulated a bloom in organisms of the genus Parabacteroides (log2-fold = 4.1, P = 0.035). Finally, transcriptional analysis of the intestine revealed enriched ontologies and pathways related to antimicrobial peptides, metabolism, and energy processing. We conclude that 2'-FL supplementation following ileocecal resection increases weight gain, energy availability through microbial community modulation, and histological changes consistent with improved adaptation.

  9. The human small intestinal microbiota is driven by rapid uptake and conversion of simple carbohydrates

    DEFF Research Database (Denmark)

    Zoetendal, Erwin G; Raes, Jeroen; van den Bogert, Bartholomeus

    2012-01-01

    The human gastrointestinal tract (GI tract) harbors a complex community of microbes. The microbiota composition varies between different locations in the GI tract, but most studies focus on the fecal microbiota, and that inhabiting the colonic mucosa. Consequently, little is known about...... the microbiota at other parts of the GI tract, which is especially true for the small intestine because of its limited accessibility. Here we deduce an ecological model of the microbiota composition and function in the small intestine, using complementing culture-independent approaches. Phylogenetic microarray...... analyses demonstrated that microbiota compositions that are typically found in effluent samples from ileostomists (subjects without a colon) can also be encountered in the small intestine of healthy individuals. Phylogenetic mapping of small intestinal metagenome of three different ileostomy effluent...

  10. Lactobacillus rhamnosus GG Outcompetes Enterococcus faecium via Mucus-Binding Pili: Evidence for a Novel and Heterospecific Probiotic Mechanism.

    Science.gov (United States)

    Tytgat, Hanne L P; Douillard, François P; Reunanen, Justus; Rasinkangas, Pia; Hendrickx, Antoni P A; Laine, Pia K; Paulin, Lars; Satokari, Reetta; de Vos, Willem M

    2016-10-01

    Vancomycin-resistant enterococci (VRE) have become a major nosocomial threat. Enterococcus faecium is of special concern, as it can easily acquire new antibiotic resistances and is an excellent colonizer of the human intestinal tract. Several clinical studies have explored the potential use of beneficial bacteria to weed out opportunistic pathogens. Specifically, the widely studied Lactobacillus rhamnosus strain GG has been applied successfully in the context of VRE infections. Here, we provide new insight into the molecular mechanism underlying the effects of this model probiotic on VRE decolonization. Both clinical VRE isolates and L. rhamnosus GG express pili on their cell walls, which are the key modulators of their highly efficient colonization of the intestinal mucosa. We found that one of the VRE pilus clusters shares considerable sequence similarity with the SpaCBA-SrtC1 pilus cluster of L. rhamnosus GG. Remarkable immunological and functional similarities were discovered between the mucus-binding pili of L. rhamnosus GG and those of the clinical E. faecium strain E1165, which was characterized at the genome level. Moreover, E. faecium strain E1165 bound efficiently to mucus, which may be prevented by the presence of the mucus-binding SpaC protein or antibodies against L. rhamnosus GG or SpaC. These results present experimental support for a novel probiotic mechanism, in which the mucus-binding pili of L. rhamnosus GG prevent the binding of a potential pathogen to the host. Hence, we provide a molecular basis for the further exploitation of L. rhamnosus GG and its pilins for prophylaxis and treatment of VRE infections. Concern about vancomycin-resistant Enterococcus faecium causing nosocomial infections is rising globally. The arsenal of antibiotic strategies to treat these infections is nearly exhausted, and hence, new treatment strategies are urgently needed. Here, we provide molecular evidence to underpin reports of the successful clinical application of

  11. Comprehensive postmortem analyses of intestinal microbiota changes and bacterial translocation in human flora associated mice.

    Directory of Open Access Journals (Sweden)

    Markus M Heimesaat

    Full Text Available BACKGROUND: Postmortem microbiological examinations are performed in forensic and medical pathology for defining uncertain causes of deaths and for screening of deceased tissue donors. Interpretation of bacteriological data, however, is hampered by false-positive results due to agonal spread of microorganisms, postmortem bacterial translocation, and environmental contamination. METHODOLOGY/PRINCIPAL FINDINGS: We performed a kinetic survey of naturally occurring postmortem gut flora changes in the small and large intestines of conventional and gnotobiotic mice associated with a human microbiota (hfa applying cultural and molecular methods. Sacrificed mice were kept under ambient conditions for up to 72 hours postmortem. Intestinal microbiota changes were most pronounced in the ileal lumen where enterobacteria and enterococci increased by 3-5 orders of magnitude in conventional and hfa mice. Interestingly, comparable intestinal overgrowth was shown in acute and chronic intestinal inflammation in mice and men. In hfa mice, ileal overgrowth with enterococci and enterobacteria started 3 and 24 hours postmortem, respectively. Strikingly, intestinal bacteria translocated to extra-intestinal compartments such as mesenteric lymphnodes, spleen, liver, kidney, and cardiac blood as early as 5 min after death. Furthermore, intestinal tissue destruction was characterized by increased numbers of apoptotic cells and neutrophils within 3 hours postmortem, whereas counts of proliferative cells as well as T- and B-lymphocytes and regulatory T-cells decreased between 3 and 12 hours postmortem. CONCLUSIONS/SIGNIFICANCE: We conclude that kinetics of ileal overgrowth with enterobacteria and enterococci in hfa mice can be used as an indicator for compromized intestinal functionality and for more precisely defining the time point of death under defined ambient conditions. The rapid translocation of intestinal bacteria starting within a few minutes after death will help

  12. Azithromycin Inhibits Mucus Hypersecretion from Airway Epithelial Cells

    Directory of Open Access Journals (Sweden)

    Takeshi Shimizu

    2012-01-01

    Full Text Available To examine the in vivo effects of the 15-member macrolide, azithromycin (AZM, on mucus hypersecretion, we induced hypertrophic and metaplastic changes of goblet cells in rat nasal epithelium by intranasal instillation of ovalbumin (OVA in OVA-sensitized rats, or by intranasal lipopolysaccharides (LPS instillation. Oral administration of AZM (5–10 mg/kg or clarithromycin (CAM, 5–10 mg/kg significantly inhibited OVA- and LPS-induced mucus production, whereas josamycin (JM or ampicillin (ABPC showed no effect. In vitro effects of AZM on airway epithelial cells were examined using NCI-H292 cells and human nasal epithelial cells cultured in air-liquid interface. Mucus secretion was evaluated by enzyme-linked immunosorbent assay using an anti-MUC5AC monoclonal antibody. AZM or CAM significantly inhibited tumor necrosis factor-α (TNF-α (20 ng/mL-induced MUC5AC secretion from NCI-H292 cells at 10−6–10−7 M, whereas JM or ABPC showed no effect. AZM significantly inhibited TNF- (20 ng/mL-induced MUC5AC secretion from human nasal epithelial cells at 10−4 M. MUC5AC mRNA expression was also significantly inhibited. These results indicate that the 15-member macrolide, AZM, exerts direct inhibitory effects on mucus secretion from airway epithelial cells and that it may be useful for the treatment of mucus hypersecretion caused by allergic inflammation and LPS stimulation.

  13. Pegylated Polyaspartamide-Polylactide-Based Nanoparticles Penetrating Cystic Fibrosis Artificial Mucus.

    Science.gov (United States)

    Craparo, Emanuela Fabiola; Porsio, Barbara; Sardo, Carla; Giammona, Gaetano; Cavallaro, Gennara

    2016-03-14

    Here, the preparation of mucus-penetrating nanoparticles for pulmonary administration of ibuprofen in patients with cystic fibrosis is described. A fluorescent derivative of α,β-poly(N-2-hydroxyethyl)-D,L-aspartamide is synthesized by derivatization with rhodamine, polylactide, and poly(ethylene glycol), to obtain polyaspartamide-polylactide derivatives with different degrees of pegylation. Starting from these copolymers, fluorescent nanoparticles with different poly(ethylene glycol) content, empty and loaded with ibuprofen, showed spherical shape, colloidal size, slightly negative ζ potential, and biocompatibility toward human bronchial epithelial cells. The high surface poly(ethylene glycol) density of fluorescent nanoparticles and poly(ethylene glycol) brush-like conformation assumed on their surface, conferred to pegylated nanoparticles the mucus-penetrating properties, properly demonstrated by assessing their ability to avoid interactions with mucus components and to penetrate cystic fibrosis artificial mucus. Finally, ibuprofen release profile and uptake capacity within human bronchial epithelial cells in the presence of cystic fibrosis artificial mucus showed how these mucus-penetrating nanoparticles could rapidly diffuse through the mucus barrier reaching the mucosal surface, where they could offer a sustained delivery of ibuprofen at the site of disease.

  14. P-gp activity and inhibition in the different regions of human intestine ex vivo.

    Science.gov (United States)

    Li, Ming; de Graaf, Inge A M; de Jager, Marina H; Groothuis, Geny M M

    2017-03-01

    Although intestinal P-glycoprotein (P-gp) has been extensively studied in vitro and in animals, its activity and the consequences of P-gp inhibition for drug disposition and toxicity in humans are still difficult to accurately extrapolate from these studies. Moreover, existing in vitro models do not take into consideration that the intestine is heterogeneous with respect to P-gp expression. Recently, we reported rat precision-cut intestinal slices (PCIS) as a physiological ex vivo model to study the regional gradient of P-gp activity and inhibition. Here we extended the application of PCIS to the human intestine. For this purpose rhodamine 123 (R123) accumulation in the presence or absence of the P-gp inhibitors verapamil, cyclosporine A, quinidine, ketoconazole, PSC833 and CP100356 was measured in PCIS of human duodenum, jejunum, ileum and colon. R123 accumulation in the presence of the P-gp inhibitors appeared to be most enhanced in the ileum compared to the other regions. Moreover, the regional differences in accumulation are in line with published differences in abundance of P-gp. The rank order of the potency of the P-gp inhibitors, reflected by their IC50 , was comparable to that in rat PCIS. However, the increase in accumulation of the P-gp substrate R123 by the inhibitors was larger in human ileum PCIS than in rat PCIS, indicating species difference in P-gp abundance. These data show that human PCIS are an appropriate ex vivo model to study the activity of intestinal P-gp and predict the inhibitory effect of drugs and of transporter-mediated drug-drug interactions in the human intestine. Copyright © 2016 John Wiley & Sons, Ltd.

  15. Intestinal epithelial cells in inflammatory bowel diseases

    Institute of Scientific and Technical Information of China (English)

    Giulia; Roda; Alessandro; Sartini; Elisabetta; Zambon; Andrea; Calafiore; Margherita; Marocchi; Alessandra; Caponi; Andrea; Belluzzi; Enrico; Roda

    2010-01-01

    The pathogenesis of inflammatory bowel diseases (IBDs) seems to involve a primary defect in one or more of the elements responsible for the maintenance of intestinal homeostasis and oral tolerance. The most important element is represented by the intestinal barrier, a complex system formed mostly by intestinal epithelial cells (IECs). IECs have an active role in producing mucus and regulating its composition; they provide a physical barrier capable of controlling antigen traff ic through the intestinal muco...

  16. Lineage-specific expression of bestrophin-2 and bestrophin-4 in human intestinal epithelial cells

    DEFF Research Database (Denmark)

    Ito, Go; Okamoto, Ryuichi; Murano, Tatsuro

    2013-01-01

    Intestinal epithelial cells (IECs) regulate the absorption and secretion of anions, such as HCO3(-) or Cl(-). Bestrophin genes represent a newly identified group of calcium-activated Cl(-) channels (CaCCs). Studies have suggested that, among the four human bestrophin-family genes, bestrophin-2...... (BEST2) and bestrophin-4 (BEST4) might be expressed within the intestinal tissue. Consistently, a study showed that BEST2 is expressed by human colonic goblet cells. However, their precise expression pattern along the gastrointestinal tract, or the lineage specificity of the cells expressing these genes...

  17. The dissolution of urinary mucus after cystoplasty.

    Science.gov (United States)

    Gillon, G; Mundy, A R

    1989-04-01

    Three agents have been tested for mucolytic activity to prevent or treat difficulties in bladder emptying following augmentation and substitution cystoplasty, particularly in patients emptying by intermittent self-catheterisation. Carbocysteine produced precipitation of mucus, which was found not to be helpful. N-acetylcysteine and urea both dissolved mucus, but urea proved to be more effective.

  18. The mucus and mucins of the goblet cells and enterocytes provide the first defense line of the gastrointestinal tract and interact with the immune system.

    Science.gov (United States)

    Pelaseyed, Thaher; Bergström, Joakim H; Gustafsson, Jenny K; Ermund, Anna; Birchenough, George M H; Schütte, André; van der Post, Sjoerd; Svensson, Frida; Rodríguez-Piñeiro, Ana M; Nyström, Elisabeth E L; Wising, Catharina; Johansson, Malin E V; Hansson, Gunnar C

    2014-07-01

    The gastrointestinal tract is covered by mucus that has different properties in the stomach, small intestine, and colon. The large highly glycosylated gel-forming mucins MUC2 and MUC5AC are the major components of the mucus in the intestine and stomach, respectively. In the small intestine, mucus limits the number of bacteria that can reach the epithelium and the Peyer's patches. In the large intestine, the inner mucus layer separates the commensal bacteria from the host epithelium. The outer colonic mucus layer is the natural habitat for the commensal bacteria. The intestinal goblet cells secrete not only the MUC2 mucin but also a number of typical mucus components: CLCA1, FCGBP, AGR2, ZG16, and TFF3. The goblet cells have recently been shown to have a novel gate-keeping role for the presentation of oral antigens to the immune system. Goblet cells deliver small intestinal luminal material to the lamina propria dendritic cells of the tolerogenic CD103(+) type. In addition to the gel-forming mucins, the transmembrane mucins MUC3, MUC12, and MUC17 form the enterocyte glycocalyx that can reach about a micrometer out from the brush border. The MUC17 mucin can shuttle from a surface to an intracellular vesicle localization, suggesting that enterocytes might control and report epithelial microbial challenge. There is communication not only from the epithelial cells to the immune system but also in the opposite direction. One example of this is IL10 that can affect and improve the properties of the inner colonic mucus layer. The mucus and epithelial cells of the gastrointestinal tract are the primary gate keepers and controllers of bacterial interactions with the host immune system, but our understanding of this relationship is still in its infancy.

  19. Membrane potential gradient is carbon monoxide-dependent in mouse and human small intestine.

    Science.gov (United States)

    Sha, Lei; Farrugia, Gianrico; Harmsen, W Scott; Szurszewski, Joseph H

    2007-08-01

    The aims of this study were to quantify the change in resting membrane potential (RMP) across the thickness of the circular muscle layer in the mouse and human small intestine and to determine whether the gradient in RMP is dependent on the endogenous production of carbon monoxide (CO). Conventional sharp glass microelectrodes were used to record the RMPs of circular smooth muscle cells at different depths in the human small intestine and in wild-type, HO2-KO, and W/W(V) mutant mouse small intestine. In the wild-type mouse and human intestine, the RMP of circular smooth muscle cells near the myenteric plexus was -65.3 +/- 2 mV and -58.4 +/- 2 mV, respectively, and -60.1 +/- 2 mV and -49.1 +/- 1 mV, respectively, in circular smooth muscle cells at the submucosal border. Oxyhemoglobin (20 microM), a trapping agent for CO, and chromium mesoporphyrin IX, an inhibitor of heme oxygenase, abolished the transwall gradient. The RMP gradients in mouse and human small intestine were not altered by N(G)-nitro-l-arginine (200 microM). No transwall RMP gradient was found in HO2-KO mice and W/W(V) mutant mice. TTX (1 microM) and 1H-[1,2,4-]oxadiazolo[4,3-a]quinoxalin-1-one (10 microM) had no effect on the RMP gradient. These data suggest that the gradient in RMP across the thickness of the circular muscle layer of mouse and human small intestine is CO dependent.

  20. Diffusion-sensitive optical coherence tomography for real-time monitoring of mucus thinning treatments

    Science.gov (United States)

    Blackmon, Richard L.; Kreda, Silvia M.; Sears, Patrick R.; Ostrowski, Lawrence E.; Hill, David B.; Chapman, Brian S.; Tracy, Joseph B.; Oldenburg, Amy L.

    2016-03-01

    Mucus hydration (wt%) has become an increasingly useful metric in real-time assessment of respiratory health in diseases like cystic fibrosis and COPD, with higher wt% indicative of diseased states. However, available in vivo rheological techniques are lacking. Gold nanorods (GNRs) are attractive biological probes whose diffusion through tissue is sensitive to the correlation length of comprising biopolymers. Through employment of dynamic light scattering theory on OCT signals from GNRs, we find that weakly-constrained GNR diffusion predictably decreases with increasing wt% (more disease-like) mucus. Previously, we determined this method is robust against mucus transport on human bronchial epithelial (hBE) air-liquid interface cultures (R2=0.976). Here we introduce diffusion-sensitive OCT (DS-OCT), where we collect M-mode image ensembles, from which we derive depth- and temporally-resolved GNR diffusion rates. DS-OCT allows for real-time monitoring of changing GNR diffusion as a result of topically applied mucus-thinning agents, enabling monitoring of the dynamics of mucus hydration never before seen. Cultured human airway epithelial cells (Calu-3 cell) with a layer of endogenous mucus were doped with topically deposited GNRs (80x22nm), and subsequently treated with hypertonic saline (HS) or isotonic saline (IS). DS-OCT provided imaging of the mucus thinning response up to a depth of 600μm with 4.65μm resolution, over a total of 8 minutes in increments of >=3 seconds. For both IS and HS conditions, DS-OCT captured changes in the pattern of mucus hydration over time. DS-OCT opens a new window into understanding mechanisms of mucus thinning during treatment, enabling real-time efficacy feedback needed to optimize and tailor treatments for individual patients.

  1. Intestinal Microbiota Distinguish Gout Patients from Healthy Humans.

    Science.gov (United States)

    Guo, Zhuang; Zhang, Jiachao; Wang, Zhanli; Ang, Kay Ying; Huang, Shi; Hou, Qiangchuan; Su, Xiaoquan; Qiao, Jianmin; Zheng, Yi; Wang, Lifeng; Koh, Eileen; Danliang, Ho; Xu, Jian; Lee, Yuan Kun; Zhang, Heping

    2016-02-08

    Current blood-based approach for gout diagnosis can be of low sensitivity and hysteretic. Here via a 68-member cohort of 33 healthy and 35 diseased individuals, we reported that the intestinal microbiota of gout patients are highly distinct from healthy individuals in both organismal and functional structures. In gout, Bacteroides caccae and Bacteroides xylanisolvens are enriched yet Faecalibacterium prausnitzii and Bifidobacterium pseudocatenulatum depleted. The established reference microbial gene catalogue for gout revealed disorder in purine degradation and butyric acid biosynthesis in gout patients. In an additional 15-member validation-group, a diagnosis model via 17 gout-associated bacteria reached 88.9% accuracy, higher than the blood-uric-acid based approach. Intestinal microbiota of gout are more similar to those of type-2 diabetes than to liver cirrhosis, whereas depletion of Faecalibacterium prausnitzii and reduced butyrate biosynthesis are shared in each of the metabolic syndromes. Thus the Microbial Index of Gout was proposed as a novel, sensitive and non-invasive strategy for diagnosing gout via fecal microbiota.

  2. In vitro and ex vivo intestinal tissue models to measure mucoadhesion of poly (methacrylate) and N-trimethylated chitosan polymers.

    Science.gov (United States)

    Keely, Simon; Rullay, Atvinder; Wilson, Carolyn; Carmichael, Adrian; Carrington, Steve; Corfield, Anthony; Haddleton, David M; Brayden, David J

    2005-01-01

    The adhesion of a range of polymers based on poly(2-(dimethylamino-ethyl) methacrylate (pDMAEMA) was assessed using human mucus-secreting and non mucus-secreting intestinal cell monolayers, HT29-MTX-E12 (E12) and HT29 monolayers, as well as excised non-everted intestinal sacs from rats. Differentiation of mucoadhesion from bioadhesion was achieved by pre-treatment with the mucolytic agent, N-acetyl cysteine (NAC). Adherence of pDMAEMA polymers was compared to that obtained with the mucoadhesive, N-trimethylated chitosan (TMC). The quantity of adherent coumarin 343-conjugated polymers to HT29, E12, and intestinal sacs was measured by fluorescence. Confocal laser scanning microscopy (CLSM), light microscopy, and fluorescent microscopy were used to provide direct evidence. Measurements of transepithelial electrical resistance (TEER), permeability to FITC-dextran 4000 (FD-4), and the release of lactate dehydrogenase (LDH) were used to assess potential cytotoxicity of polymers. Adherence of unquaternized and of 10%, 24%, and 32% methyl iodide-quaternized pDMAEMA polymers was measured in E12, HT29, and sacs. All pDMAEMA polymers showed significantly higher levels of adhesion to mucus (mucoadhesion) than to epithelium (bioadhesion). Colocalization of pDMAEMA with mucus was confirmed in E12 by microscopy. TMC showed equally high levels of mucoadhesion as unquaternized and 24% quaternized pDMAEMA, but displayed higher levels of bioadhesion. pDMAEMA-based polymers demonstrated lower levels of adherence to E12 and rat sacs in the presence of NAC, whereas adherence of TMC was unchanged. pDMAEMA significantly decreased the permeability of FD-4 across E12 monolayers and sacs and was less cytotoxic in E12 than in HT29. In contrast, TMC increased the permeability of FD-4 across E12 and sacs and was less cytotoxic in E12 than in HT29. Human mucus-producing E12 monolayers can be used to assess polymer mucoadhesion and give similar data to isolated rat intestinal sacs. p

  3. Mucus-penetrating nanoparticles for vaginal and gastrointestinal drug delivery

    Science.gov (United States)

    Ensign-Hodges, Laura

    A method that could provide more uniform and longer-lasting drug delivery to mucosal surfaces holds the potential to greatly improve the effectiveness of prophylactic and therapeutic approaches for numerous diseases and conditions, including sexually transmitted infections and inflammatory bowel disease. However, the body's natural defenses, including adhesive, rapidly cleared mucus linings coating nearly all entry points to the body not covered by skin, has limited the effectiveness of drug and gene delivery by nanoscale delivery systems. Here, we investigate the use of muco-inert mucus-penetrating nanoparticles (MPP) for improving vaginal and gastrointestinal drug delivery. Conventional hydrophobic nanoparticles strongly adhere to mucus, facilitating rapid clearance from the body. Here, we demonstrate that mucoadhesive polystyrene nanoparticles (conventional nanoparticles, CP) become mucus-penetrating in human cervicovaginal mucus (CVM) after pretreatment with sufficient concentrations of Pluronic F127. Importantly, the diffusion rate of large MPP did not change in F127 pretreated CVM, implying there is no affect on the native pore structure of CVM. Additionally, there was no increase in inflammatory cytokine release in the vaginal tract of mice after daily application of 1% F127 for one week. Importantly, HSV virus remains adherent in F127-pretreated CVM. Mucosal epithelia use osmotic gradients for fluid absorption and secretion. We hypothesized that hypotonically-induced fluid uptake could be advantageous for rapidly delivering drugs through mucus to the vaginal epithelium. We evaluated hypotonic formulations for delivering water-soluble drugs and for drug delivery with MPP. Hypotonic formulations markedly increased the rate at which drugs and MPP reached the epithelial surface. Additionally, hypotonic formulations greatly enhanced drug and MPP delivery to the entire epithelial surface, including deep into the vaginal folds (rugae) that isotonic formulations

  4. Activation of AMPK inhibits cholera toxin stimulated chloride secretion in human and murine intestine.

    Directory of Open Access Journals (Sweden)

    Ailín C Rogers

    Full Text Available Increased intestinal chloride secretion through chloride channels, such as the cystic fibrosis transmembrane conductance regulator (CFTR, is one of the major molecular mechanisms underlying enterotoxigenic diarrhea. It has been demonstrated in the past that the intracellular energy sensing kinase, the AMP-activated protein kinase (AMPK, can inhibit CFTR opening. We hypothesized that pharmacological activation of AMPK can abrogate the increased chloride flux through CFTR occurring during cholera toxin (CTX mediated diarrhea. Chloride efflux was measured in isolated rat colonic crypts using real-time fluorescence imaging. AICAR and metformin were used to activate AMPK in the presence of the secretagogues CTX or forskolin (FSK. In order to substantiate our findings on the whole tissue level, short-circuit current (SCC was monitored in human and murine colonic mucosa using Ussing chambers. Furthermore, fluid accumulation was measured in excised intestinal loops. CTX and forskolin (FSK significantly increased chloride efflux in isolated colonic crypts. The increase in chloride efflux could be offset by using the AMPK activators AICAR and metformin. In human and mouse mucosal sheets, CTX and FSK increased SCC. AICAR and metformin inhibited the secretagogue induced rise in SCC, thereby confirming the findings made in isolated crypts. Moreover, AICAR decreased CTX stimulated fluid accumulation in excised intestinal segments. The present study suggests that pharmacological activation of AMPK effectively reduces CTX mediated increases in intestinal chloride secretion, which is a key factor for intestinal water accumulation. AMPK activators may therefore represent a supplemental treatment strategy for acute diarrheal illness.

  5. Glucose induces intestinal human UDP-glucuronosyltransferase (UGT) 1A1 to prevent neonatal hyperbilirubinemia.

    Science.gov (United States)

    Aoshima, Naoya; Fujie, Yoshiko; Itoh, Tomoo; Tukey, Robert H; Fujiwara, Ryoichi

    2014-09-11

    Inadequate calorie intake or starvation has been suggested as a cause of neonatal jaundice, which can further cause permanent brain damage, kernicterus. This study experimentally investigated whether additional glucose treatments induce the bilirubin-metabolizing enzyme--UDP-glucuronosyltransferase (UGT) 1A1--to prevent the onset of neonatal hyperbilirubinemia. Neonatal humanized UGT1 (hUGT1) mice physiologically develop jaundice. In this study, UGT1A1 expression levels were determined in the liver and small intestine of neonatal hUGT1 mice that were orally treated with glucose. In the hUGT1 mice, glucose induced UGT1A1 in the small intestine, while it did not affect the expression of UGT1A1 in the liver. UGT1A1 was also induced in the human intestinal Caco-2 cells when the cells were cultured in the presence of glucose. Luciferase assays demonstrated that not only the proximal region (-1300/-7) of the UGT1A1 promoter, but also distal region (-6500/-4050) were responsible for the induction of UGT1A1 in the intestinal cells. Adequate calorie intake would lead to the sufficient expression of UGT1A1 in the small intestine to reduce serum bilirubin levels. Supplemental treatment of newborns with glucose solution can be a convenient and efficient method to treat neonatal jaundice while allowing continuous breastfeeding.

  6. 16s rRNA Identification of Pediococcus spp. from Broiler and Studies of Adherence Ability on Immobilized Mucus

    Directory of Open Access Journals (Sweden)

    Ema Damayanti

    2015-11-01

    Full Text Available The objectives of this research were to study taxonomical status of lactic acid bacteria (LAB isolated from broiler and adherence ability on mucus in vitro. Molecular analysis was performed by analyzing 16S rRNA gene using universal primer. The adherence assay on mucus was carried out using microplate method with total plate count (TPC, absorbance (A550 and confirmed by scanning electron microscopy (SEM. The results of this studies revealed that three of LAB isolates have closed relation to Pediococcus acidilactici (99.9% species.Three isolates of P. acidilactici have adherence ability on broiler mucus higher than that on porcine mucin with an adherence percentage of 55.5% versus 50.8% and absorbance A550 of 0.061 versus 0.051, respectively. The highest adherence ability showed by P. acidilactici R02 with adherence percentage was 59.3% and absorbance A550 = 0.068. Adherence on mucus were affected by the addition of 3 g/l of gastric juice and 0.3% (b/v of bile salt. Adherence analysis using SEM also showed that the adherence on broiler mucus was higher than the adherence on porcine mucin. Altogether this adherence studies, suggest that three isolates of P. acidilactici LAB were capable of colonizing host intestinal mucus in vitro as important property to be promising probiotic bacteria for broiler.Key words : adherence, broiler, Pediococcus, mucus, 16S rRNA

  7. Mucoactive agents for airway mucus hypersecretory diseases.

    Science.gov (United States)

    Rogers, Duncan F

    2007-09-01

    Airway mucus hypersecretion is a feature of a number of severe respiratory diseases, including asthma, chronic obstructive pulmonary disease (COPD), and cystic fibrosis (CF). However, each disease has a different airway inflammatory response, with consequent, and presumably linked, mucus hypersecretory phenotype. Thus, it is possible that optimal treatment of the mucus hypersecretory element of each disease should be disease-specific. Nevertheless, mucoactive drugs are a longstanding and popular therapeutic option, and numerous compounds (eg, N-acetylcysteine, erdosteine, and ambroxol) are available for clinical use worldwide. However, rational recommendation of these drugs in guidelines for management of asthma, COPD, or CF has been hampered by lack of information from well-designed clinical trials. In addition, the mechanism of action of most of these drugs is unknown. Consequently, although it is possible to categorize them according to putative mechanisms of action, as expectorants (aid and/or induce cough), mucolytics (thin mucus), mucokinetics (facilitate cough transportability), and mucoregulators (suppress mechanisms underlying chronic mucus hypersecretion, such as glucocorticosteroids), it is likely that any beneficial effects are due to activities other than, or in addition to, effects on mucus. It is also noteworthy that the mucus factors that favor mucociliary transport (eg, thin mucus gel layer, "ideal" sol depth, and elasticity greater than viscosity) are opposite to those that favor cough effectiveness (thick mucus layer, excessive sol height, and viscosity greater than elasticity), which indicates that different mucoactive drugs would be required for treatment of mucus obstruction in proximal versus distal airways, or in patients with an impaired cough reflex. With the exception of mucoregulatory agents, whose primary action is unlikely to be directed against mucus, well-designed clinical trials are required to unequivocally determine the

  8. Novel mucus-penetrating liposomes as a potential oral drug delivery system: preparation, in vitro characterization, and enhanced cellular uptake

    Science.gov (United States)

    Li, Xiuying; Chen, Dan; Le, Chaoyi; Zhu, Chunliu; Gan, Yong; Hovgaard, Lars; Yang, Mingshi

    2011-01-01

    Background The aim of this study was to investigate the intestinal mucus-penetrating properties and intestinal cellular uptake of two types of liposomes modified by Pluronic F127 (PF127). Methods The two types of liposomes, ie, PF127-inlaid liposomes and PF127-adsorbed liposomes, were prepared by a thin-film hydration method followed by extrusion, in which coumarin 6 was loaded as a fluorescence marker. A modified Franz diffusion cell mounted with the intestinal mucus of rats was used to study the diffusion characteristics of the two types of PF127 liposomes. Cell uptake studies were conducted in Caco-2 cells and analyzed using confocal laser scanning microcopy as well as flow cytometry. Results The diffusion efficiency of the two types of PF127-modified liposomes through intestinal rat mucus was 5–7-fold higher than that of unmodified liposomes. Compared with unmodified liposomes, PF127-inlaid liposomes showed significantly higher cellular uptake of courmarin 6. PF127-adsorbed liposomes showed a lower cellular uptake. Moreover, and interestingly, the two types of PF127-modified liposomes showed different cellular uptake mechanisms in Caco-2 cells. Conclusion PF127-inlaid liposomes with improved intestinal mucus-penetrating ability and enhanced cellular uptake might be a potential carrier candidate for oral drug delivery. PMID:22163166

  9. Analysis of diversity and function of the human small intestinal microbiota

    NARCIS (Netherlands)

    Booijink, C.C.G.M.

    2009-01-01

    The gastrointestinal (GI) tract is the main site where the conversion and absorption of food components takes place in humans. As the small intestine is the first site of interaction between the microbiota and ingested food, knowledge about the microbial composition as well as functionality is essen

  10. Human intestinal flora and the induction of chronic arthritis : studies in an animal model.

    NARCIS (Netherlands)

    A.J. Severijnen

    1990-01-01

    textabstractThe etiology of rheumatoid arthritis (RA), a chronic joint inflammation, is unknown. A microbial involvement is suspected, but no particular microorganism has been incriminated. The human intestinal microflora is an abundant and continuous source of bacterial antigens and may be involved

  11. Microbial Eco-Physiology of the human intestinal tract: a flow cytometric approach

    NARCIS (Netherlands)

    Amor, Ben K.

    2004-01-01

    This thesis describes a multifaceted approach to further enhance our view of the complex human intestinal microbial ecosystem. This approach combines me advantages of flow cyrometry (FCM), a single cell and high-throughput technology, and molecular techniques that have proven themselves to be invalu

  12. The mucin degrader Akkermansia muciniphila is an abundant resident of the human intestinal tract

    NARCIS (Netherlands)

    Derrien, M.M.N.; Collado, M.C.; Ben-Amor, K.; Salminen, S.; Vos, de W.M.

    2008-01-01

    A 16S rRNA-targeted probe, MUC-1437, was designed and validated in order to determine the presence and numbers of cells of Akkermansia muciniphila, a mucin degrader, in the human intestinal tract. As determined by fluorescent in situ hybridization, A. muciniphila accounted more than 1% of the total

  13. Draft Genome Sequence of Veillonella parvula HSIVP1, Isolated from the Human Small Intestine

    NARCIS (Netherlands)

    Bogert, B. van den; Boekhorst, J.; Smid, E.J.; Zoetendal, E.G.; Kleerebezem, M.

    2013-01-01

    Veillonella species are frequently encountered commensals in the human small intestine. Here, we report the draft genome sequence of the first cultured representative from this ecosystem, Veillonella parvula strain HSIVP1. The genome is predicted to encode all the necessary enzymes required for the

  14. Complete amino acid sequence of human intestinal aminopeptidase N as deduced from cloned cDNA

    DEFF Research Database (Denmark)

    Cowell, G M; Kønigshøfer, E; Danielsen, E M

    1988-01-01

    The complete primary structure (967 amino acids) of an intestinal human aminopeptidase N (EC 3.4.11.2) was deduced from the sequence of a cDNA clone. Aminopeptidase N is anchored to the microvillar membrane via an uncleaved signal for membrane insertion. A domain constituting amino acid 250...

  15. High-throughput analysis of the impact of antibiotics on the human intestinal microbiota composition

    NARCIS (Netherlands)

    Ladirat, S.E.; Schols, H.A.; Nauta, A.; Schoterman, M.H.C.; Keijser, B.J.F.; Montijn, R.C.; Gruppen, H.; Schuren, F.H.J.

    2013-01-01

    Antibiotic treatments can lead to a disruption of the human microbiota. In this in-vitro study, the impact of antibiotics on adult intestinal microbiota was monitored in a new high-throughput approach: a fermentation screening-platform was coupled with a phylogenetic microarray analysis

  16. Analysis of diversity and function of the human small intestinal microbiota

    NARCIS (Netherlands)

    Booijink, C.C.G.M.

    2009-01-01

    The gastrointestinal (GI) tract is the main site where the conversion and absorption of food components takes place in humans. As the small intestine is the first site of interaction between the microbiota and ingested food, knowledge about the microbial composition as well as functionality is

  17. Microbial Eco-Physiology of the human intestinal tract: a flow cytometric approach

    NARCIS (Netherlands)

    Amor, Ben K.

    2004-01-01

    This thesis describes a multifaceted approach to further enhance our view of the complex human intestinal microbial ecosystem. This approach combines me advantages of flow cyrometry (FCM), a single cell and high-throughput technology, and molecular techniques that have proven themselves to be

  18. Microbial Eco-Physiology of the human intestinal tract: a flow cytometric approach

    NARCIS (Netherlands)

    Amor, Ben K.

    2004-01-01

    This thesis describes a multifaceted approach to further enhance our view of the complex human intestinal microbial ecosystem. This approach combines me advantages of flow cyrometry (FCM), a single cell and high-throughput technology, and molecular techniques that have proven themselves to be invalu

  19. The genome of Akkermansia muciniphila, a dedicated intestinal mucin degrader, and its use in exploring intestinal metagenomes.

    Directory of Open Access Journals (Sweden)

    Mark W J van Passel

    Full Text Available BACKGROUND: The human gastrointestinal tract contains a complex community of microbes, fulfilling important health-promoting functions. However, this vast complexity of species hampers the assignment of responsible organisms to these functions. Recently, Akkermansia muciniphila, a new species from the deeply branched phylum Verrucomicrobia, was isolated from the human intestinal tract based on its capacity to efficiently use mucus as a carbon and nitrogen source. This anaerobic resident is associated with the protective mucus lining of the intestines. METHODOLOGY/PRINCIPAL FINDINGS: In order to uncover the functional potential of A. muciniphila, its genome was sequenced and annotated. It was found to contain numerous candidate mucinase-encoding genes, but lacking genes encoding canonical mucus-binding domains. Numerous phage-associated sequences found throughout the genome indicate that viruses have played an important part in the evolution of this species. Furthermore, we mined 37 GI tract metagenomes for the presence, and genetic diversity of Akkermansia sequences. Out of 37, eleven contained 16S ribosomal RNA gene sequences that are >95% identical to that of A. muciniphila. In addition, these libraries were found to contain large amounts of Akkermansia DNA based on average nucleotide identity scores, which indicated in one subject co-colonization by different Akkermansia phylotypes. An additional 12 libraries also contained Akkermansia sequences, making a total of ∼16 Mbp of new Akkermansia pangenomic DNA. The relative abundance of Akkermansia DNA varied between <0.01% to nearly 4% of the assembled metagenomic reads. Finally, by testing a large collection of full length 16S sequences, we find at least eight different representative species in the genus Akkermansia. CONCLUSIONS/SIGNIFICANCE: These large repositories allow us to further mine for genetic heterogeneity and species diversity in the genus Akkermansia, providing novel insight

  20. Type I collagen as an extracellular matrix for the in vitro growth of human small intestinal epithelium

    National Research Council Canada - National Science Library

    Jabaji, Ziyad; Brinkley, Garrett J; Khalil, Hassan A; Sears, Connie M; Lei, Nan Ye; Lewis, Michael; Stelzner, Matthias; Martín, Martín G; Dunn, James C Y

    2014-01-01

    .... There are concerns over the applicability of Matrigel-based methods for future human therapies. We investigated type I collagen as an alternative for the culture of human intestinal epithelial cells...

  1. Type I Collagen as an Extracellular Matrix for the In Vitro Growth of Human Small Intestinal Epithelium: e107814

    National Research Council Canada - National Science Library

    Ziyad Jabaji; Garrett J Brinkley; Hassan A Khalil; Connie M Sears; Nan Ye Lei; Michael Lewis; Matthias Stelzner; Martín G Martín; James C Y Dunn

    2014-01-01

    .... There are concerns over the applicability of Matrigel-based methods for future human therapies. We investigated type I collagen as an alternative for the culture of human intestinal epithelial cells...

  2. Isolation and characterization of cytotoxic effector cells and antibody producing cells from human intestine.

    Science.gov (United States)

    MacDermott, R P

    1985-01-01

    We have examined the ability of intestinal and peripheral blood mononuclear cells isolated from patients with inflammatory bowel disease to mediate killing against cell line targets in spontaneous, antibody-dependent, lectin-induced, and interferon-induced cell-mediated cytotoxicity assays, as well as responsiveness in the allogeneic mixed leukocyte reaction, and effector capabilities in cell-mediated lympholysis. IMC were poor mediators of spontaneous or antibody-dependent cellular cytotoxicity with cell line cells as targets (in comparison to normal PBMC, but were capable of killing antibody coated chicken red blood cells. Although IMC were capable of responding to allogeneic cell surface antigens in the mixed leukocyte reaction, they did not exhibit effector function in cell-mediated lympholysis. Mitogenic lectins induced cell-mediated cytotoxicity by isolated intestinal mononuclear cells from controls and patients. HFIF induces cytotoxicity by control but not inflammatory bowel disease intestinal cells. Pokeweed mitogen was the lectin which induced the greatest amount of killing against human cell line targets. We therefore speculate that exogenous agents, or endogenous factors released during viral infection, could play a role in inducing cell mediated cytotoxic damage to the intestine in inflammatory bowel disease patients. In addition, the functional differences between IMC and PBMC indicate that intestinal MNC may have unique cell capabilities which must be better understood prior to the delineation of immunopathologic events in solid organ tissues. We have also examined the secretion of IgA, IgM, and IgG by isolated human IMC, human bone marrow MNC from rib specimens, and PBMC from patients with CD, UC, SLE, or Henoch-Schoenlein purpura (HSP). Control IMC exhibited high spontaneous secretion of IgA, while intestinal MNC from UC and CD patients exhibited only modest increases in IgA secretion. PBMC from patients with CD, UC, SLE, or HSP exhibited markedly

  3. Glycosylation of human fetal mucins: a similar repertoire of O-glycans along the intestinal tract.

    Science.gov (United States)

    Robbe-Masselot, Catherine; Maes, Emmanuel; Rousset, Monique; Michalski, Jean-Claude; Capon, Calliope

    2009-05-01

    Intestinal mucins are very high molecular weight glycoproteins secreted by goblet cells lining the crypt and the surface of the colonic mucosa. Profound alterations of mucin O-glycans are observed in diseases such as cancer and inflammation, modifying the function of the cell and its antigenic and adhesive properties. Based on immunohistochemical studies, certain cancer- and inflammation- associated glycans have been defined as oncofetal antigens. However, little or no chemical analysis has allowed the structural elucidation of O-glycans expressed on human fetal mucins. In this paper, mucins were isolated from different regions of the normal human intestine (ileum, right, transverse and left colon) of eight fetuses with A, B or O blood group. After alkaline borohydride treatment, the released oligosaccharides were investigated by nanoESI Q-TOF MS/MS (electrospray ionization quadrupole time-of-flight tandem mass spectrometry). More than 117 different glycans were identified, mainly based on core 2 structures. Some core 1, 3 and 4 oligosaccharides were also found. Most of the structures were acidic with NeuAc residues mainly alpha2-6 linked to the N-acetylgalactosaminitol and sulphate residues 3-linked to galactose or 6-linked to GlcNAc. In contrast to adult human intestinal mucins, Sda/Cad determinants were not expressed on fetal mucin O-glycans and the presence of an acidic gradient along the intestinal tract was not observed. Similar patterns of glycosylation were found in each part of the intestine and the level of expression of the major oligosaccharides was in the same order of magnitude. This study could help determining new oncofetal antigens, which can be exploited for the diagnosis or the treatment of intestinal diseases.

  4. Investigation of the interactions between Chrysanthemum morifolium flowers extract and intestinal bacteria from human and rat.

    Science.gov (United States)

    Tao, Jin-Hua; Duan, Jin-Ao; Qian, Yi-Yun; Qian, Da-Wei; Guo, Jian-Ming

    2016-11-01

    Flos Chrysanthemi, dried flower of Chrysanthemum morifolium Ramat, has drawn much attention recently owing to its potential beneficial health effects for human. Flos Chrysanthemi products are usually taken orally and metabolized by intestinal microflora. However, there has been no investigation of the comprehensive metabolic profile of the Flos Chrysanthemi extract by intestinal flora owing to its chemical complexity and the limitations of analytical methods. In this paper, a rapid, sensitive and automated analysis method, ultra-performance liquid chromatography/quadrupole time of flight mass spectrometry including MS(E) technology and automated data processing Metabolynx™ software, was developed and successfully applied for the biotransformation and metabolic profile of flavonoids in the Flos Chrysanthemi extract by intestinal flora from human and rat. A total of 32 metabolites were detected and tentatively identified in human and rat intestinal bacterial samples. These metabolites indicated that hydrolysis, hydroxylation, acetylation, methylation, hydrogenation and deoxygenation were the major conversion pathways of flavonoids in the Flos Chrysanthemi extract in vitro. Furthermore, the effects of the Flos Chrysanthemi extract on the growth of different intestinal bacteria were detected using an Emax precision microplate reader. Certain pathogenic bacteria such as Enterobacter, Enterococcus, Clostridium and Bacteroides were significantly inhibited by Flos Chrysanthemi, while commensal probiotics such as Lactobacillus and Bifidobacterium were moderately promoted. Our observation provided further evidence for the importance of intestinal bacteria in the metabolism and potential activity of the Flos Chrysanthemi extract. The results will also be helpful for the further pharmacokinetic study of Flos Chrysanthemi and to unravel how it works in vivo.

  5. Human intestinal macrophages display profound inflammatory anergy despite avid phagocytic and bacteriocidal activity

    OpenAIRE

    Smythies, Lesley E.; Sellers, Marty; Ronald H Clements; Mosteller-Barnum, Meg; Meng, Gang; Benjamin, William H.; Orenstein, Jan M.; Smith, Phillip D.

    2005-01-01

    Intestinal macrophages, which are thought to orchestrate mucosal inflammatory responses, have received little investigative attention compared with macrophages from other tissues. Here we show that human intestinal macrophages do not express innate response receptors, including the receptors for LPS (CD14), Fcα (CD89), Fcγ (CD64, CD32, CD16), CR3 (CD11b/CD18), and CR4 (CD11c/CD18); the growth factor receptors IL-2 (CD25) and IL-3 (CD123); and the integrin LFA-1 (CD11a/CD18). Moreover, residen...

  6. Human intestinal microbiota: cross-talk with the host and its potential role in colorectal cancer.

    Science.gov (United States)

    Candela, Marco; Guidotti, Marco; Fabbri, Alessia; Brigidi, Patrizia; Franceschi, Claudio; Fiorentini, Carla

    2011-02-01

    In this review, we discuss the multifactorial role of intestinal microbiota in colorectal cancer. The peculiar metabolism of dietary compounds of the individual microbiota complement, its overall immunostimulation and immunomodulatory activity, and eventually the production of toxins that perturb the regulation of cell growth, define the balance of positive and negative risk factors for colorectal cancer development. Moreover, shaping the composition of the human intestinal microbiota, diet has an indirect impact in determining the balance between health and disease. The integration of diet, microbial, and host factors in a system approach is mandatory to determine the overall balance of risk and protective factors for colorectal cancer onset.

  7. Chromosomal localization of the human apolipoprotein B gene and detection of homologous RNA in monkey intestine

    Energy Technology Data Exchange (ETDEWEB)

    Deeb, S.S.; Disteche, C.; Motulsky, A.G.; Lebo, R.V.; Kan, Y.W.

    1986-01-01

    A cDNA clone of the human apolipoprotein B-100 was used as a hybridization probe to detect homologous sequences in both flow-sorted and in situ metaphase chromosomes. The results indicate that the gene encoding this protein is on the distal end of the short arm of chromosome 2 (2p23-2p24). RNA isolated from monkey small intestine contained sequences (6.5 and 18 kilobases) homologous to the cDNA of apolipoprotein B-100. These results are consistent with the hypothesis that one gene codes for both the intestinal (B-48) and the hepatic (B-100) forms.

  8. Preparation and characterization of mucus-penetrating papain/poly(acrylic acid) nanoparticles for oral drug delivery applications

    Science.gov (United States)

    Müller, Christiane; Leithner, Katharina; Hauptstein, Sabine; Hintzen, Fabian; Salvenmoser, Willi; Bernkop-Schnürch, Andreas

    2013-01-01

    Particle diffusion through the intestinal mucosal barrier is restricted by the viscoelastic and adhesive properties of the mucus gel layer, preventing their penetration to the underlying absorptive endothelial cells. To overcome this natural barrier, we developed nanoparticles which have a remarkable ability to cleave mucoglycoprotein substructures responsible for the structural and rheological properties of mucus. After rheological screening of various mucolytic proteases, nanoparticles composed of poly(acrylic acid) and papain were prepared and characterized regarding particle size and zeta potential. Analysis of nanoparticles showed mean diameters sub-200 nm (162.8-198.5 nm) and negative zeta potentials advancing the mobility in mucus gel. Using diffusion chamber studies and the rotating diffusion tubes method, we compared the transport rates of papain modified (PAPC) and unaltered poly(acrylic acid) (PAA) particles through freshly excised intestinal porcine mucus. Results of the diffusion assays demonstrated strongly enhanced permeation behavior of PAPC particles owing to local mucus disruption by papain. Improved transport rates, reduction in mucus viscosity and the retarded release of hydrophilic macromolecular compounds make proteolytic enzyme functionalized nanoparticles of substantial interest for improved targeted drug delivery at mucosal surfaces. Although cytotoxicity tests of the nanoparticles could not be performed, safety of papain and PAA was already verified making PAPC particles a promising candidate in the pharmaceutical field of research. The focus of the present study was the development of particles which penetrate the mucus barrier to approach the underlying epithelium. Improvements of particles that penetrate the mucus followed by cell uptake in this direction are ongoing.

  9. Preparation and characterization of mucus-penetrating papain/poly(acrylic acid) nanoparticles for oral drug delivery applications

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, Christiane; Leithner, Katharina; Hauptstein, Sabine; Hintzen, Fabian [Center for Molecular Biosciences Innsbruck, University of Innsbruck, CCB-Centrum for Chemistry und Biomedicine, Department of Pharmaceutical Technology, Institute of Pharmacy (Austria); Salvenmoser, Willi [University of Innsbruck, Department for Evolutionary Developmental Biology, Institute of Zoology and Center for Molecular Biosciences (Austria); Bernkop-Schnuerch, Andreas, E-mail: andreas.bernkop@uibk.ac.at [Center for Molecular Biosciences Innsbruck, University of Innsbruck, CCB-Centrum for Chemistry und Biomedicine, Department of Pharmaceutical Technology, Institute of Pharmacy (Austria)

    2013-01-15

    Particle diffusion through the intestinal mucosal barrier is restricted by the viscoelastic and adhesive properties of the mucus gel layer, preventing their penetration to the underlying absorptive endothelial cells. To overcome this natural barrier, we developed nanoparticles which have a remarkable ability to cleave mucoglycoprotein substructures responsible for the structural and rheological properties of mucus. After rheological screening of various mucolytic proteases, nanoparticles composed of poly(acrylic acid) and papain were prepared and characterized regarding particle size and zeta potential. Analysis of nanoparticles showed mean diameters sub-200 nm (162.8-198.5 nm) and negative zeta potentials advancing the mobility in mucus gel. Using diffusion chamber studies and the rotating diffusion tubes method, we compared the transport rates of papain modified (PAPC) and unaltered poly(acrylic acid) (PAA) particles through freshly excised intestinal porcine mucus. Results of the diffusion assays demonstrated strongly enhanced permeation behavior of PAPC particles owing to local mucus disruption by papain. Improved transport rates, reduction in mucus viscosity and the retarded release of hydrophilic macromolecular compounds make proteolytic enzyme functionalized nanoparticles of substantial interest for improved targeted drug delivery at mucosal surfaces. Although cytotoxicity tests of the nanoparticles could not be performed, safety of papain and PAA was already verified making PAPC particles a promising candidate in the pharmaceutical field of research. The focus of the present study was the development of particles which penetrate the mucus barrier to approach the underlying epithelium. Improvements of particles that penetrate the mucus followed by cell uptake in this direction are ongoing.

  10. CFTR is a tumor suppressor gene in murine and human intestinal cancer.

    Science.gov (United States)

    Than, B L N; Linnekamp, J F; Starr, T K; Largaespada, D A; Rod, A; Zhang, Y; Bruner, V; Abrahante, J; Schumann, A; Luczak, T; Niemczyk, A; O'Sullivan, M G; Medema, J P; Fijneman, R J A; Meijer, G A; Van den Broek, E; Hodges, C A; Scott, P M; Vermeulen, L; Cormier, R T

    2016-08-11

    CFTR, the cystic fibrosis (CF) gene, encodes for the CFTR protein that plays an essential role in anion regulation and tissue homeostasis of various epithelia. In the gastrointestinal (GI) tract CFTR promotes chloride and bicarbonate secretion, playing an essential role in ion and acid-base homeostasis. Cftr has been identified as a candidate driver gene for colorectal cancer (CRC) in several Sleeping Beauty DNA transposon-based forward genetic screens in mice. Further, recent epidemiological and clinical studies indicate that CF patients are at high risk for developing tumors in the colon. To investigate the effects of CFTR dysregulation on GI cancer, we generated Apc(Min) mice that carried an intestinal-specific knockout of Cftr. Our results indicate that Cftr is a tumor suppressor gene in the intestinal tract as Cftr mutant mice developed significantly more tumors in the colon and the entire small intestine. In Apc(+/+) mice aged to ~1 year, Cftr deficiency alone caused the development of intestinal tumors in >60% of mice. Colon organoid formation was significantly increased in organoids created from Cftr mutant mice compared with wild-type controls, suggesting a potential role of Cftr in regulating the intestinal stem cell compartment. Microarray data from the Cftr-deficient colon and the small intestine identified dysregulated genes that belong to groups of immune response, ion channel, intestinal stem cell and other growth signaling regulators. These associated clusters of genes were confirmed by pathway analysis using Ingenuity Pathway Analysis and gene set enrichment analysis (GSEA). We also conducted RNA Seq analysis of tumors from Apc(+/+) Cftr knockout mice and identified sets of genes dysregulated in tumors including altered Wnt β-catenin target genes. Finally we analyzed expression of CFTR in early stage human CRC patients stratified by risk of recurrence and found that loss of expression of CFTR was significantly associated with poor disease

  11. Metagenomics of the human intestinal tract: from who is there to what is done there

    OpenAIRE

    Lapaque, Nicolas; Doré, Joël; Blottière, Hervé

    2015-01-01

    The human gastro-intestinal tract is colonized by 10(6)-10(14) microorganisms from the three domains, eukaria, archaea and bacteria that are collectively referred as the human gut microbiota. Gut microbiota actively contributes to the digestion of the nutrients, mainly the fibers otherwise undigested by the host, and participate to the host capacity of energy recovery from food. It plays also a key role in gut homeostasis, impacting on its barrier function and regulating the immune and metabo...

  12. Inhibition of human pancreatic and biliary output but not intestinal motility by physiological intraileal lipid loads

    DEFF Research Database (Denmark)

    Keller, Jutta; Holst, Jens Juul; Layer, Peter

    2005-01-01

    . Physiological postprandial ileal lipid concentrations dose dependently inhibited human digestive pancreatic protease and bile acid output, but not intestinal motor activity. Thus physiological postprandial ileal nutrient exposure may be of importance for the termination of digestive secretory responses......Lipid perfusion into the distal ileal lumen at supraphysiological loads inhibits pancreatic exocrine secretion and gastrointestinal motility in humans. In the present study, we sought to determine the effects of physiological postprandial intraileal lipid concentrations on endogenously stimulated...

  13. Supplementation with Lactobacillus plantarum WCFS1 prevents Decline of Mucus Barrier in Colon of Accelerated Aging Ercc1-/Δ7 Mice

    Directory of Open Access Journals (Sweden)

    Adriaan A Van Beek

    2016-10-01

    Full Text Available Although it is clear that probiotics improve intestinal barrier function, little is known about the effects of probiotics on the aging intestine. We investigated effects of 10-wk bacterial supplementation of Lactobacillus plantarum WCFS1, Lactobacillus casei BL23, or Bifidobacterium breve DSM20213 on gut barrier and immunity in 16-week-old accelerated aging Ercc1-/Δ7 mice, which have a median lifespan of ~20wk, and their wild-type littermates. The colonic barrier in Ercc1-/Δ7 mice was characterized by a thin (<10µm mucus layer. L. plantarum prevented this decline in mucus integrity in Ercc1-/Δ7 mice, whereas B. breve exacerbated it. Bacterial supplementations affected the expression of immune-related genes, including Toll-like receptor 4. Regulatory T cell frequencies were increased in the mesenteric lymph nodes of L. plantarum- and L. casei-treated Ercc1-/Δ7 mice. L. plantarum- and L. casei-treated Ercc1-/Δ7 mice showed increased specific antibody production in a T cell-dependent immune response in vivo. By contrast, the effects of bacterial supplementation on wild-type control mice were negligible. Thus, supplementation with L. plantarum – but not with L. casei and B. breve – prevented the decline in the mucus barrier in Ercc1-/Δ7 mice. Our data indicate that age is an important factor influencing beneficial or detrimental effects of candidate probiotics. These findings also highlight the need for caution in translating beneficial effects of probiotics observed in young animals or humans to the elderly.

  14. Supplementation with Lactobacillus plantarum WCFS1 Prevents Decline of Mucus Barrier in Colon of Accelerated Aging Ercc1−/Δ7 Mice

    Science.gov (United States)

    van Beek, Adriaan A.; Sovran, Bruno; Hugenholtz, Floor; Meijer, Ben; Hoogerland, Joanne A.; Mihailova, Violeta; van der Ploeg, Corine; Belzer, Clara; Boekschoten, Mark V.; Hoeijmakers, Jan H. J.; Vermeij, Wilbert P.; de Vos, Paul; Wells, Jerry M.; Leenen, Pieter J. M.; Nicoletti, Claudio; Hendriks, Rudi W.; Savelkoul, Huub F. J.

    2016-01-01

    Although it is clear that probiotics improve intestinal barrier function, little is known about the effects of probiotics on the aging intestine. We investigated effects of 10-week bacterial supplementation of Lactobacillus plantarum WCFS1, Lactobacillus casei BL23, or Bifidobacterium breve DSM20213 on gut barrier and immunity in 16-week-old accelerated aging Ercc1−/Δ7 mice, which have a median lifespan of ~20 weeks, and their wild-type littermates. The colonic barrier in Ercc1−/Δ7 mice was characterized by a thin (< 10 μm) mucus layer. L. plantarum prevented this decline in mucus integrity in Ercc1−/Δ7 mice, whereas B. breve exacerbated it. Bacterial supplementations affected the expression of immune-related genes, including Toll-like receptor 4. Regulatory T cell frequencies were increased in the mesenteric lymph nodes of L. plantarum- and L. casei-treated Ercc1−/Δ7 mice. L. plantarum- and L. casei-treated Ercc1−/Δ7 mice showed increased specific antibody production in a T cell-dependent immune response in vivo. By contrast, the effects of bacterial supplementation on wild-type control mice were negligible. Thus, supplementation with L. plantarum – but not with L. casei and B. breve – prevented the decline in the mucus barrier in Ercc1−/Δ7 mice. Our data indicate that age is an important factor influencing beneficial or detrimental effects of candidate probiotics. These findings also highlight the need for caution in translating beneficial effects of probiotics observed in young animals or humans to the elderly. PMID:27774093

  15. Effects of drugs on mucus clearance.

    Science.gov (United States)

    Houtmeyers, E; Gosselink, R; Gayan-Ramirez, G; Decramer, M

    1999-08-01

    Mucociliary clearance (MCC), the process in which airway mucus together with substances trapped within are moved out of the lungs, is an important defence mechanism of the human body. Drugs may alter this process, such that it is necessary to know the effect of the drugs on MCC. Indeed, agents stimulating MCC may be used therapeutically in respiratory medicine, especially in patients suspected of having an impairment of their mucociliary transport system. In contrast, caution should be taken with drugs depressing MCC as an undesired side-effect, independently of their therapeutic indication. Since cough clearance (CC) serves as a back-up system when MCC fails, the influence of drugs must be examined not only on MCC but also on CC. Ultimately, the clinical repercussions of alterations in mucus transport induced by drug administration must be studied. Tertiary ammonium compounds (anticholinergics), aspirin, anaesthetic agents and benzodiazepines have been shown to be capable of depressing the mucociliary transport system. Cholinergics, methylxanthines, sodium cromoglycate, hypertonic saline, saline as well as water aerosol have been shown to increase MCC. Adrenergic antagonists, guaifenesin, S-carboxymethylcysteine, sodium 2-mercapto-ethane sulphonate and frusemide have been reported not to alter the mucociliary transport significantly. Amiloride, uridine 5'-triphosphate (UTP), quaternary ammonium compounds (anticholinergics), adrenergic agonists, corticosteroids, recombinant human deoxyribonuclease (rhDNase), N-acetylcysteine, bromhexine and ambroxol have been reported either not to change or to augment MCC. Indirect data suggest that surfactant as well as antibiotics may improve the mucociliary transport system. As for the influence of drugs on CC, amiloride and rhDNase have been demonstrated to increase the effectiveness of cough. A trend towards an improved CC was noted after treatment with adrenergic agonists. The anticholinergic agent ipratropium bromide, which

  16. Reductive dechlorination of methoxychlor and DDT by human intestinal bacterium Eubacterium limosum under anaerobic conditions.

    Science.gov (United States)

    Yim, You-Jin; Seo, Jiyoung; Kang, Su-Il; Ahn, Joong-Hoon; Hur, Hor-Gil

    2008-04-01

    Methoxychlor [1,1,1-trichloro-2,2-bis(p-methoxyphenyl)ethane], a substitute for 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane (DDT), is a compound of environmental concern because of potential long-term health risks related to its endocrine-disrupting and carcinogenic potency. In order to determine the metabolic fate of methoxychlor and DDT in the human intestinal gut, Eubacterium limosum (ATCC 8486), a strict anaerobe isolated from the human intestine that is capable of O-demethylation toward O-methylated isoflavones, was used as a model intestinal microbial organism. Under anaerobic incubation conditions, E. limosum completely transformed methoxychlor and DDT in 16 days. Based on gas chromatography-mass chromatography analyses, the metabolites produced from methoxychlor and DDT by E. limosum were confirmed to be 1,1-dichloro-2,2-bis(p-methoxyphenyl)ethane (methoxydichlor) and 1,1-dichloro-2,2-bis(p-chlorophenyl)ethane (DDD), respectively. This study suggests that E. limosum in the human intestinal gut might be a participant in the reductive dechlorination of methoxychlor to the more antiandrogenic active methoxydichlor.

  17. Interaction of Salmonella enterica Serovar Typhimurium with Intestinal Organoids Derived from Human Induced Pluripotent Stem Cells.

    Science.gov (United States)

    Forbester, Jessica L; Goulding, David; Vallier, Ludovic; Hannan, Nicholas; Hale, Christine; Pickard, Derek; Mukhopadhyay, Subhankar; Dougan, Gordon

    2015-07-01

    The intestinal mucosa forms the first line of defense against infections mediated by enteric pathogens such as salmonellae. Here we exploited intestinal "organoids" (iHOs) generated from human induced pluripotent stem cells (hIPSCs) to explore the interaction of Salmonella enterica serovar Typhimurium with iHOs. Imaging and RNA sequencing were used to analyze these interactions, and clear changes in transcriptional signatures were detected, including altered patterns of cytokine expression after the exposure of iHOs to bacteria. S. Typhimurium microinjected into the lumen of iHOs was able to invade the epithelial barrier, with many bacteria residing within Salmonella-containing vacuoles. An S. Typhimurium invA mutant defective in the Salmonella pathogenicity island 1 invasion apparatus was less capable of invading the iHO epithelium. Hence, we provide evidence that hIPSC-derived organoids are a promising model of the intestinal epithelium for assessing interactions with enteric pathogens.

  18. Human milk oligosaccharide effects on intestinal function and inflammation after preterm birth in pigs

    DEFF Research Database (Denmark)

    Rasmussen, Stine O.; Martin, Lena; Østergaard, Mette V.

    2017-01-01

    Human milk oligosaccharides (HMOs) may mediate prebiotic and anti-inflammatory effects in newborns. This is particularly important for preterm infants who are highly susceptible to intestinal dysfunction and necrotizing enterocolitis (NEC). We hypothesized that HMO supplementation of infant formula...... (IF) improves intestinal function, bacterial colonization and NEC resistance immediately after preterm birth, as tested in a preterm pig model. Mixtures of HMOs were investigated in intestinal epithelial cells and in preterm pigs (n=112) fed IF supplemented without (CON) or with a mixture of four HMOs...... (4-HMO) or >25 HMOs (25-HMO, 5-10 g/L given for 5 or 11 days). The 25-HMO blend decreased cell proliferation and both HMO blends decreased lipopolysaccharide-induced interleukin-8 secretion in IPEC-J2 cells, relative to control (P

  19. Identification of interstitial cells of Cajal. Significance for studies of human small intestine and colon

    DEFF Research Database (Denmark)

    Rumessen, J J

    1994-01-01

    electron microscopical studies emphasized similarities between ICC and fibroblasts. In our early studies of ICC in the external musculature of mouse small intestine, we identified ICC by their characteristic morphology and topography, and we analyzed the relation between ICC, autonomic nerves and smooth......Interstitial cells of Cajal (ICC) were described a century ago by Ramón y Cajal a.o. as primitive neurons in the intestines. In the period 1900-1960 a large number of light microscopical studies of ICC were published, in which ICC were identified by heir characteristic morphology. After 1960...... functions (mechanoreceptive, mediating inhibitory nervous input). In spite of this possible fundamental importance for G-I motility, ICC have not been adequately described or even identified in human intestine, and hence, never included in ultrastructural studies of G-I neuropathology. This survey presents...

  20. Protein abundance of clinically relevant multidrug transporters along the entire length of the human intestine.

    Science.gov (United States)

    Drozdzik, Marek; Gröer, Christian; Penski, Jette; Lapczuk, Joanna; Ostrowski, Marek; Lai, Yurong; Prasad, Bhagwat; Unadkat, Jashvant D; Siegmund, Werner; Oswald, Stefan

    2014-10-01

    Intestinal transporters are crucial determinants in the oral absorption of many drugs. We therefore studied the mRNA expression (N = 33) and absolute protein content (N = 10) of clinically relevant transporters in healthy epithelium of the duodenum, the proximal and distal jejunum and ileum, and the ascending, transversal, descending, and sigmoidal colon of six organ donors (24-54 years). In the small intestine, the abundance of nearly all studied proteins ranged between 0.2 and 1.6 pmol/mg with the exception of those of OCT3 (intestinal segment. ABCB1, ABCG2, PEPT1, and ASBT were significantly more abundant in jejunum and ileum than in colon. In contrast to this, the level of expression of ABCC2, ABCC3, and OCT3 was found to be highest in colon. Site-dependent differences in the levels of gene and protein expression were observed for ABCB1 and ASBT. Significant correlations between mRNA and protein levels have been found for ABCG2, ASBT, OCT3, and PEPT1 in the small intestine. Our data provide further physiological pieces of the puzzle required to predict intestinal drug absorption in humans.

  1. Human Intestinal Parasite Burden and Poor Sanitation in Rural Alabama.

    Science.gov (United States)

    McKenna, Megan L; McAtee, Shannon; Bryan, Patricia E; Jeun, Rebecca; Ward, Tabitha; Kraus, Jacob; Bottazzi, Maria E; Hotez, Peter J; Flowers, Catherine C; Mejia, Rojelio

    2017-09-05

    Hookworm infection affects 430 million people worldwide, causing iron deficiency, impaired cognitive development, and stunting in children. Because of the environmental conditions needed for the hookworm life-cycle, this parasite is endemic to resource-limited countries. Necator americanus was endemic in the southern United States before improvement of sewage disposal systems and eradication programs. With continued poverty, poor sanitation, and an environment suitable for the hookworm life-cycle in some regions of the southern United States, a current prevalence study using modern molecular diagnostics is warranted. Lowndes County, Alabama, was chosen as the study site given previous high hookworm burdens, degree of poverty, and use of open-sewage systems. Participants were interviewed, and stool, serum, and soil samples were tested for nine intestinal parasites using a multiparallel quantitative real-time PCR (qPCR) and enzyme-linked immunosorbent assays . We found that, among 24 households, 42.4% reported exposure to raw sewage within their home, and from 55 stool samples, 19 (34.5%) tested positive for N. americanus, four (7.3%) for Strongyloides stercoralis, and one (1.8%) for Entamoeba histolytica. Stool tested positive for N. americanus contained low levels of parasite DNA (geometric mean 0.0302 fg/µL). Soil studies detected one (2.9%) Cryptosporidium species, and Toxocara serology assay detected one (5.2%) positive in this population. Individuals living in this high-risk environment within the United States continue to have stool samples positive for N. americanus. Gastrointestinal parasites known to be endemic to developing countries are identifiable in American poverty regions, and areas with lower disease burden are more likely to be identified by using qPCR.

  2. Effect of bisacodyl on the structure and function of rodent and human intestine.

    Science.gov (United States)

    Saunders, D R; Sillery, J; Rachmilewitz, D; Rubin, C E; Tytgat, G N

    1977-05-01

    The effect of bisacodyl on intestinal structure and function was investigated. Net water transport was measured under steady state conditions in vivo during single pass infusions of rodent and of human intestinal segments. Each segment served as its own control. Bisacodyl inhibited water absorption in rat jejunum, ileum, and colon. The degree of inhibition was linearly related to the logarithm of the bisacodyl concentration over the range of 0.05 to 2.0 mg per 100 ml. In human jejunal segments, bisacodyl, 1 mg per 100 ml, caused net water secretion. Bisacodyl, 5 mg every 6 hr, increased ileostomy output by 15% when it was fed to 5 patients with established ileostomies. By light microscopy, bisacodyl, 2 mg per 100 ml, erased cytoplasmic and nuclear detail within surface absorptive cells of rat intestine. By electron microscopy, the involved cells contained sparse and abnormal cytoplasmic organelles and nuclei which were deficient in chromatin. These results suggest that the laxative effect of bisacodyl is related to its ability to inhibit intestinal water absorption. Reduced absorption may be secondary to changes in surface absorptive cells.

  3. Adhesion Properties of Lactic Acid Bacteria on Intestinal Mucin

    Directory of Open Access Journals (Sweden)

    Keita Nishiyama

    2016-09-01

    Full Text Available Lactic acid bacteria (LAB are Gram-positive bacteria that are natural inhabitants of the gastrointestinal (GI tracts of mammals, including humans. Since Mechnikov first proposed that yogurt could prevent intestinal putrefaction and aging, the beneficial effects of LAB have been widely demonstrated. The region between the duodenum and the terminal of the ileum is the primary region colonized by LAB, particularly the Lactobacillus species, and this region is covered by a mucus layer composed mainly of mucin-type glycoproteins. The mucus layer plays a role in protecting the intestinal epithelial cells against damage, but is also considered to be critical for the adhesion of Lactobacillus in the GI tract. Consequently, the adhesion exhibited by lactobacilli on mucin has attracted attention as one of the critical factors contributing to the persistent beneficial effects of Lactobacillus in a constantly changing intestinal environment. Thus, understanding the interactions between Lactobacillus and mucin is crucial for elucidating the survival strategies of LAB in the GI tract. This review highlights the properties of the interactions between Lactobacillus and mucin, while concomitantly considering the structure of the GI tract from a histochemical perspective.

  4. Adhesion Properties of Lactic Acid Bacteria on Intestinal Mucin

    Science.gov (United States)

    Nishiyama, Keita; Sugiyama, Makoto; Mukai, Takao

    2016-01-01

    Lactic acid bacteria (LAB) are Gram-positive bacteria that are natural inhabitants of the gastrointestinal (GI) tracts of mammals, including humans. Since Mechnikov first proposed that yogurt could prevent intestinal putrefaction and aging, the beneficial effects of LAB have been widely demonstrated. The region between the duodenum and the terminal of the ileum is the primary region colonized by LAB, particularly the Lactobacillus species, and this region is covered by a mucus layer composed mainly of mucin-type glycoproteins. The mucus layer plays a role in protecting the intestinal epithelial cells against damage, but is also considered to be critical for the adhesion of Lactobacillus in the GI tract. Consequently, the adhesion exhibited by lactobacilli on mucin has attracted attention as one of the critical factors contributing to the persistent beneficial effects of Lactobacillus in a constantly changing intestinal environment. Thus, understanding the interactions between Lactobacillus and mucin is crucial for elucidating the survival strategies of LAB in the GI tract. This review highlights the properties of the interactions between Lactobacillus and mucin, while concomitantly considering the structure of the GI tract from a histochemical perspective. PMID:27681930

  5. Activation of Intestinal Human Pregnane X Receptor Protects against Azoxymethane/Dextran Sulfate Sodium–Induced Colon Cancer

    OpenAIRE

    Cheng, Jie; Fang, Zhong-Ze; Nagaoka, Kenjiro; Okamoto, Minoru; Qu, Aijuan; Tanaka, Naoki; Kimura, Shioko; Gonzalez, Frank J.

    2014-01-01

    The role of intestinal human pregnane X receptor (PXR) in colon cancer was determined through investigation of the chemopreventive role of rifaximin, a specific agonist of intestinal human PXR, toward azoxymethane (AOM)/dextran sulfate sodium (DSS)–induced colon cancer. Rifaximin treatment significantly decreased the number of colon tumors induced by AOM/DSS treatment in PXR-humanized mice, but not wild-type or Pxr-null mice. Additionally, rifaximin treatment markedly increased the survival r...

  6. Short- and long-term effects of oral vancomycin on the human intestinal microbiota

    Science.gov (United States)

    Isaac, Sandrine; Scher, Jose U.; Djukovic, Ana; Jiménez, Nuria; Littman, Dan R.; Abramson, Steven B.; Pamer, Eric G.; Ubeda, Carles

    2017-01-01

    Background Oral vancomycin remains the mainstay of therapy for severe infections produced by Clostridium difficile, the most prevalent cause of healthcare-associated infectious diarrhoea in developed countries. However, its short- and long-term effects on the human intestinal microbiota remain largely unknown. Methods We utilized high-throughput sequencing to analyse the effects of vancomycin on the faecal human microbiota up to 22 weeks post-antibiotic cessation. The clinical relevance of the observed microbiota perturbations was studied in mice. Results During vancomycin therapy, most intestinal microbiota genera and operational taxonomic units (OTUs) were depleted in all analysed subjects, including all baseline OTUs from the phylum Bacteroidetes. This was accompanied by a vast expansion of genera associated with infections, including Klebsiella and Escherichia/Shigella. Following antibiotic cessation, marked differences in microbiota resilience were observed among subjects. While some individuals recovered a microbiota close to baseline composition, in others, up to 89% of abundant OTUs could no longer be detected. The clinical relevance of the observed microbiota changes was further demonstrated in mice, which developed analogous microbiota alterations. During vancomycin treatment, mice were highly susceptible to intestinal colonization by an antibiotic-resistant pathogen and, upon antibiotic cessation, a less-resilient microbiota allowed higher levels of pathogen colonization. Conclusions Oral vancomycin induces drastic and consistent changes in the human intestinal microbiota. Upon vancomycin cessation, the microbiota recovery rate varied considerably among subjects, which could influence, as validated in mice, the level of susceptibility to pathogen intestinal colonization. Our results demonstrate the negative long-term effects of vancomycin, which should be considered as a fundamental aspect of the cost–benefit equation for antibiotic prescription. PMID

  7. Short- and long-term effects of oral vancomycin on the human intestinal microbiota.

    Science.gov (United States)

    Isaac, Sandrine; Scher, Jose U; Djukovic, Ana; Jiménez, Nuria; Littman, Dan R; Abramson, Steven B; Pamer, Eric G; Ubeda, Carles

    2017-01-01

    Oral vancomycin remains the mainstay of therapy for severe infections produced by Clostridium difficile, the most prevalent cause of healthcare-associated infectious diarrhoea in developed countries. However, its short- and long-term effects on the human intestinal microbiota remain largely unknown. We utilized high-throughput sequencing to analyse the effects of vancomycin on the faecal human microbiota up to 22 weeks post-antibiotic cessation. The clinical relevance of the observed microbiota perturbations was studied in mice. During vancomycin therapy, most intestinal microbiota genera and operational taxonomic units (OTUs) were depleted in all analysed subjects, including all baseline OTUs from the phylum Bacteroidetes. This was accompanied by a vast expansion of genera associated with infections, including Klebsiella and Escherichia/Shigella. Following antibiotic cessation, marked differences in microbiota resilience were observed among subjects. While some individuals recovered a microbiota close to baseline composition, in others, up to 89% of abundant OTUs could no longer be detected. The clinical relevance of the observed microbiota changes was further demonstrated in mice, which developed analogous microbiota alterations. During vancomycin treatment, mice were highly susceptible to intestinal colonization by an antibiotic-resistant pathogen and, upon antibiotic cessation, a less-resilient microbiota allowed higher levels of pathogen colonization. Oral vancomycin induces drastic and consistent changes in the human intestinal microbiota. Upon vancomycin cessation, the microbiota recovery rate varied considerably among subjects, which could influence, as validated in mice, the level of susceptibility to pathogen intestinal colonization. Our results demonstrate the negative long-term effects of vancomycin, which should be considered as a fundamental aspect of the cost-benefit equation for antibiotic prescription. © The Author 2016. Published by Oxford

  8. Comparative Genomics Analysis of Streptococcus Isolates from the Human Small Intestine Reveals their Adaptation to a Highly Dynamic Ecosystem

    NARCIS (Netherlands)

    Bogert, B. van den; Boekhorst, J.; Herrmann, R.; Smid, E.J.; Zoetendal, E.G.; Kleerebezem, M.

    2013-01-01

    The human small-intestinal microbiota is characterised by relatively large and dynamic Streptococcus populations. In this study, genome sequences of small-intestinal streptococci from S. mitis, S. bovis, and S. salivarius species-groups were determined and compared with those from 58 Streptococcus s

  9. Comparative Genomics Analysis of Streptococcus Isolates from the Human Small Intestine Reveals their Adaptation to a Highly Dynamic Ecosystem

    NARCIS (Netherlands)

    Bogert, van den B.; Boekhorst, te J.; Herrmann, R.; Smid, E.J.; Zoetendal, E.G.; Kleerebezem, M.

    2013-01-01

    The human small-intestinal microbiota is characterised by relatively large and dynamic Streptococcus populations. In this study, genome sequences of small-intestinal streptococci from S. mitis, S. bovis, and S. salivarius species-groups were determined and compared with those from 58 Streptococcus

  10. Megaselia scalaris causing human intestinal myiasis in Egypt.

    Science.gov (United States)

    Mazayad, Said A M; Rifaat, Manal M A

    2005-04-01

    Megaselia scalaris is a worldwide distributed insect of medical importance. In a laboratory-based study, stool samples with undefined maggot infestation were examined and the presence of M. scalaris maggots was confirmed. Binocular stereo-microscopy was used for identification of the maggots. Larvae were allowed to develop into adults onto a human stool culture. The larvae and the emerged flies were identified using standard keys. This may be the first report of M. scalaris as a causative agent of human myiasis in Egypt. Details of the third instar larva, pupa and adults were given.

  11. Similarity of hydrolyzing activity of human and rat small intestinal disaccharidases

    Directory of Open Access Journals (Sweden)

    Oku T

    2011-06-01

    Full Text Available Tsuneyuki Oku¹, Kenichi Tanabe¹, Shigeharu Ogawa², Naoki Sadamori¹, Sadako Nakamura¹¹Graduate School of Human Health Science, University of Nagasaki, Siebold, Nagayo, Japan; ²Juzenkai Hospital, Kagomachi, Nagasaki, JapanBackground: The purpose of this study was to clarify whether it is possible to extrapolate results from studies of the hydrolyzing activity of disaccharidases from rats to humans.Materials and methods: We measured disaccharidase activity in humans and rats using identical preparation and assay methods, and investigated the similarity in hydrolyzing activity. Small intestinal samples without malignancy were donated by five patients who had undergone bladder tumor surgery, and homogenates were prepared to measure disaccharidase activity. Adult rat homogenates were prepared using small intestine.Results: Maltase activity was the highest among the five disaccharidases, followed by sucrase and then palatinase in humans and rats. Trehalase activity was slightly lower than that of palatinase in humans and was similar to that of sucrase in rats. Lactase activity was the lowest in humans, but was similar to that of palatinase in rats. Thus, the hydrolyzing activity of five disaccharidases was generally similar in humans and rats. The relative activity of sucrose and palatinase versus maltase was generally similar between humans and rats. The ratio of rat to human hydrolyzing activity of maltase, sucrase, and palatinase was 1.9–3.1, but this was not a significant difference. Leaf extract from Morus alba strongly inhibited the activity of maltase, sucrase, and palatinase, but not trehalase and lactase, and the degree of inhibition was similar in humans and rats. L-arabinose mildly inhibited sucrase activity, but hardly inhibited the activity of maltase, palatinase, trehalase and lactase in humans and rats. The digestibility of 1-kestose, galactosylsucrose, and panose by small intestinal enzymes was very similar between humans and

  12. TMEM16A mediates the hypersecretion of mucus induced by Interleukin-13.

    Science.gov (United States)

    Lin, Jiachen; Jiang, Youfan; Li, Li; Liu, Yanan; Tang, Hui; Jiang, Depeng

    2015-06-10

    Previous studies showed that the Ca(2+)-activated Cl(-) channel (CaCC) was involved in the pathogenesis of mucus hypersecretion induced by Interleukin-13 (IL-13). However, the mechanisms underlying the process were unknown. Recently, transmembrane protein 16A (TMEM16A) was identified as the channel underlying the CaCC current. The aim of the current study was to investigate whether the TMEM16A channel is part of the mechanism underlying IL-13-induced mucus hypersecretion. We observed that both TMEM16A mRNA and protein expression were significantly up-regulated after treatment with IL-13 in human bronchial epithelial 16 (HBE 16) cells, which correlated with an increase in mucus production. Additionally, mucus hypersecretion in rat airways was induced by intratracheal instillation of IL-13 and similar increases were observed in the expression of TMEM16A mRNA and protein in the bronchial epithelium. Niflumic acid (NA), a selective antagonist of CaCC, markedly blocked IL-13-induced mucin (MUC) 5AC mRNA and protein production in vivo and in vitro. Further investigation with HBE16 cells revealed that TMEM16A overexpression clearly promoted mucus production, IκBα phosphorylation, and p65 accumulation in the nucleus. The loss of TMEM16A resulted in inhibition of mucus production, and the TMEM16A-mediated production of MUC5AC was significantly blocked by a nuclear factor-kappa B (NF-κB) inhibitor. Therefore, the TMEM16A channel acts upstream of NF-κB in the regulation of mucus production. This is the first demonstration that the TMEM16A-NF-κB pathway is positively involved in IL-13-induced mucus production, which provides novel insight into the molecular mechanism of mucin overproduction.

  13. The Mucus of Actinia equina (Anthozoa, Cnidaria: An Unexplored Resource for Potential Applicative Purposes

    Directory of Open Access Journals (Sweden)

    Loredana Stabili

    2015-08-01

    Full Text Available The mucus produced by many marine organisms is a complex mixture of proteins and polysaccharides forming a weak watery gel. It is essential for vital processes including locomotion, navigation, structural support, heterotrophic feeding and defence against a multitude of environmental stresses, predators, parasites, and pathogens. In the present study we focused on mucus produced by a benthic cnidarian, the sea anemone Actinia equina (Linnaeus, 1758 for preventing burial by excess sedimentation and for protection. We investigated some of the physico-chemical properties of this matrix such as viscosity, osmolarity, electrical conductivity, protein, carbohydrate, and total lipid contents. Some biological activities such as hemolytic, cytotoxic, and antibacterial lysozyme-like activities were also studied. The A. equina mucus is mainly composed by water (96.2% ± 0.3%, whereas its dry weight is made of 24.2% ± 1.3% proteins and 7.8% ± 0.2% carbohydrates, with the smallest and largest components referable to lipids (0.9% and inorganic matter (67.1%. The A. equina mucus matrix exhibited hemolytic activity on rabbit erythrocytes, cytotoxic activity against the tumor cell line K562 (human erythromyeloblastoid leukemia and antibacterial lysozyme-like activity. The findings from this study improve the available information on the mucus composition in invertebrates and have implications for future investigations related to exploitation of A. equina and other sea anemones’ mucus as a source of bioactive compounds of high pharmaceutical and biotechnological interest.

  14. Bioactive potency of epidermal mucus extracts from greasy grouper, Epinephelus tauvina (Forsskal, 1775

    Directory of Open Access Journals (Sweden)

    Ganesh Manikantan

    2016-07-01

    Full Text Available Objective: To study the bio-potency of epidermal mucus from Epinephelus tauvina. Methods: Mucus was extracted with acidic, organic and aqueous solvents. Protein, carbohydrate, lipid, amino acid and fatty acid content of mucus extracts were quantified by UV-spectrophotometer, high performance liquid chromatography and gas chromatographymass spectrometer, respectively. Antimicrobial activity was tested against five human and fish pathogens by using agar well diffusion method. The molecular weight of peptides was determined using sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The haemolytic activity of extracts was tested against chick, goat, cow and human red blood cell. Results: Protein contributed with maximum of 26.25% in crude mucus. Arginine was recorded maximum of (133.9 nmol/mL in crude mucus. 2,4,6-Decatrienoic acid and bis (a-chloroethyl sulfone were confirmed in organic extract. The antimicrobial activity of acidic extract was significant. Among the human pathogens, maximum zone of inhibition [(26.0 ± 0.3 mm] was observed against Proteus mirabilis. Whereas, among fish pathogens maximum zone of inhibition [(25.0 ± 0.1 mm] was observed against Vibrio parahemolyticus. The activity of other two extracts was not remarkable. The molecular weight of peptides ranged from 115.5– 37.1 kDa in acidic extract was determined. Chicken and goat blood were found to be highly vulnerable to the lysis. Conclusions: The whole mucus could be a promising source with numerous bioactivepotency. Consequently, this preliminary information suggested that mucus is a source of novel antimicrobial agents for fish and human health related applications.

  15. Bioactive potency of epidermal mucus extracts from greasy grouper,Epinephelus tauvina (Forsskal, 1775)

    Institute of Scientific and Technical Information of China (English)

    Ganesh Manikantan; Somasundarannair Lyla; Syed Ajmal Khan; Packiaraj Vijayanand; George Edward Gnana Jothi

    2016-01-01

    Objective: To study the bio-potency of epidermal mucus fromEpinephelus tauvina. Methods: Mucus was extracted with acidic, organic and aqueous solvents. Protein, carbohydrate, lipid, amino acid and fatty acid content of mucus extracts were quantified by UV-spectrophotometer, high performance liquid chromatography and gas chromatography-mass spectrometer, respectively. Antimicrobial activity was tested against five human and fish pathogens by using agar well diffusion method. The molecular weight of peptides was determined using sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The haemolytic activity of extracts was tested against chick, goat, cow and human red blood cell. Results:Protein contributed with maximum of 26.25% in crude mucus. Arginine was recorded maximum of (133.9 nmol/mL) in crude mucus. 2,4,6-Decatrienoic acid and bis (a-chloroethyl) sulfone were confirmed in organic extract. The antimicrobial activity of acidic extract was significant. Among the human pathogens, maximum zone of inhibition [(26.0 ± 0.3) mm] was observed againstProteus mirabilis. Whereas, among fish pathogens maximum zone of inhibition [(25.0 ± 0.1) mm] was observed againstVibrio parahemolyticus. The activity of other two extracts was not remarkable. The molecular weight of peptides ranged from 115.5–37.1 kDa in acidic extract was determined. Chicken and goat blood were found to be highly vulnerable to the lysis. Conclusions: The whole mucus could be a promising source with numerous bioactive- potency. Consequently, this preliminary information suggested that mucus is a source of novel antimicrobial agents for fish and human health related applications.

  16. Comparative genomics analysis of Streptococcus isolates from the human small intestine reveals their adaptation to a highly dynamic ecosystem.

    Directory of Open Access Journals (Sweden)

    Bartholomeus Van den Bogert

    Full Text Available The human small-intestinal microbiota is characterised by relatively large and dynamic Streptococcus populations. In this study, genome sequences of small-intestinal streptococci from S. mitis, S. bovis, and S. salivarius species-groups were determined and compared with those from 58 Streptococcus strains in public databases. The Streptococcus pangenome consists of 12,403 orthologous groups of which 574 are shared among all sequenced streptococci and are defined as the Streptococcus core genome. Genome mining of the small-intestinal streptococci focused on functions playing an important role in the interaction of these streptococci in the small-intestinal ecosystem, including natural competence and nutrient-transport and metabolism. Analysis of the small-intestinal Streptococcus genomes predicts a high capacity to synthesize amino acids and various vitamins as well as substantial divergence in their carbohydrate transport and metabolic capacities, which is in agreement with observed physiological differences between these Streptococcus strains. Gene-specific PCR-strategies enabled evaluation of conservation of Streptococcus populations in intestinal samples from different human individuals, revealing that the S. salivarius strains were frequently detected in the small-intestine microbiota, supporting the representative value of the genomes provided in this study. Finally, the Streptococcus genomes allow prediction of the effect of dietary substances on Streptococcus population dynamics in the human small-intestine.

  17. Comparative Genomics Analysis of Streptococcus Isolates from the Human Small Intestine Reveals their Adaptation to a Highly Dynamic Ecosystem

    Science.gov (United States)

    Van den Bogert, Bartholomeus; Boekhorst, Jos; Herrmann, Ruth; Smid, Eddy J.; Zoetendal, Erwin G.; Kleerebezem, Michiel

    2013-01-01

    The human small-intestinal microbiota is characterised by relatively large and dynamic Streptococcus populations. In this study, genome sequences of small-intestinal streptococci from S. mitis, S. bovis, and S. salivarius species-groups were determined and compared with those from 58 Streptococcus strains in public databases. The Streptococcus pangenome consists of 12,403 orthologous groups of which 574 are shared among all sequenced streptococci and are defined as the Streptococcus core genome. Genome mining of the small-intestinal streptococci focused on functions playing an important role in the interaction of these streptococci in the small-intestinal ecosystem, including natural competence and nutrient-transport and metabolism. Analysis of the small-intestinal Streptococcus genomes predicts a high capacity to synthesize amino acids and various vitamins as well as substantial divergence in their carbohydrate transport and metabolic capacities, which is in agreement with observed physiological differences between these Streptococcus strains. Gene-specific PCR-strategies enabled evaluation of conservation of Streptococcus populations in intestinal samples from different human individuals, revealing that the S. salivarius strains were frequently detected in the small-intestine microbiota, supporting the representative value of the genomes provided in this study. Finally, the Streptococcus genomes allow prediction of the effect of dietary substances on Streptococcus population dynamics in the human small-intestine. PMID:24386196

  18. Comparative genomics analysis of Streptococcus isolates from the human small intestine reveals their adaptation to a highly dynamic ecosystem.

    Science.gov (United States)

    Van den Bogert, Bartholomeus; Boekhorst, Jos; Herrmann, Ruth; Smid, Eddy J; Zoetendal, Erwin G; Kleerebezem, Michiel

    2013-01-01

    The human small-intestinal microbiota is characterised by relatively large and dynamic Streptococcus populations. In this study, genome sequences of small-intestinal streptococci from S. mitis, S. bovis, and S. salivarius species-groups were determined and compared with those from 58 Streptococcus strains in public databases. The Streptococcus pangenome consists of 12,403 orthologous groups of which 574 are shared among all sequenced streptococci and are defined as the Streptococcus core genome. Genome mining of the small-intestinal streptococci focused on functions playing an important role in the interaction of these streptococci in the small-intestinal ecosystem, including natural competence and nutrient-transport and metabolism. Analysis of the small-intestinal Streptococcus genomes predicts a high capacity to synthesize amino acids and various vitamins as well as substantial divergence in their carbohydrate transport and metabolic capacities, which is in agreement with observed physiological differences between these Streptococcus strains. Gene-specific PCR-strategies enabled evaluation of conservation of Streptococcus populations in intestinal samples from different human individuals, revealing that the S. salivarius strains were frequently detected in the small-intestine microbiota, supporting the representative value of the genomes provided in this study. Finally, the Streptococcus genomes allow prediction of the effect of dietary substances on Streptococcus population dynamics in the human small-intestine.

  19. Type I collagen as an extracellular matrix for the in vitro growth of human small intestinal epithelium.

    Directory of Open Access Journals (Sweden)

    Ziyad Jabaji

    Full Text Available We previously reported in vitro maintenance and proliferation of human small intestinal epithelium using Matrigel, a proprietary basement membrane product. There are concerns over the applicability of Matrigel-based methods for future human therapies. We investigated type I collagen as an alternative for the culture of human intestinal epithelial cells.Human small intestine was procured from fresh surgical pathology specimens. Small intestinal crypts were isolated using EDTA chelation. Intestinal subepithelial myofibroblasts were isolated from a pediatric sample and expanded in vitro. After suspension in Matrigel or type I collagen gel, crypts were co-cultured above a confluent layer of myofibroblasts. Crypts were also grown in monoculture with exposure to myofibroblast conditioned media; these were subsequently sub-cultured in vitro and expanded with a 1∶2 split ratio. Cultures were assessed with light microscopy, RT-PCR, histology, and immunohistochemistry.Collagen supported viable human epithelium in vitro for at least one month in primary culture. Sub-cultured epithelium expanded through 12 passages over 60 days. Histologic sections revealed polarized columnar cells, with apical brush borders and basolaterally located nuclei. Collagen-based cultures gave rise to monolayer epithelial sheets at the gel-liquid interface, which were not observed with Matrigel. Immunohistochemical staining identified markers of differentiated intestinal epithelium and myofibroblasts. RT-PCR demonstrated expression of α-smooth muscle actin and vimentin in myofibroblasts and E-Cadherin, CDX2, villin 1, intestinal alkaline phosphatase, chromogranin A, lysozyme, and Lgr5 in epithelial cells. These markers were maintained through several passages.Type I collagen gel supports long-term in vitro maintenance and expansion of fully elaborated human intestinal epithelium. Collagen-based methods yield familiar enteroid structures as well as a new pattern of sheet

  20. Generation of L cells in mouse and human small intestine organoids

    DEFF Research Database (Denmark)

    Petersen, Natalia; Reimann, Frank; Bartfeld, Sina;

    2014-01-01

    functional L cells from three-dimensional cultures of mouse and human intestinal crypts. We show that short-chain fatty acids selectively increase the number of L cells, resulting in an elevation of GLP-1 release. This is accompanied by the upregulation of transcription factors associated with the endocrine......Upon a nutrient challenge, L cells produce glucagon-like peptide 1 (GLP-1), a powerful stimulant of insulin release. Strategies to augment endogenous GLP-1 production include promoting L-cell differentiation and increasing L-cell number. Here we present a novel in vitro platform to generate...... lineage of intestinal stem cell development. Thus, our platform allows us to study and modulate the development of L cells in mouse and human crypts as a potential basis for novel therapeutic strategies in patients with type 2 diabetes....

  1. Metabolomics analysis of Cistus monspeliensis leaf extract on energy metabolism activation in human intestinal cells.

    Science.gov (United States)

    Shimoda, Yoichi; Han, Junkyu; Kawada, Kiyokazu; Smaoui, Abderrazak; Isoda, Hiroko

    2012-01-01

    Energy metabolism is a very important process to improve and maintain health from the point of view of physiology. It is well known that the intracellular ATP production is contributed to energy metabolism in cells. Cistus monspeliensis is widely used as tea, spices, and medical herb; however, it has not been focusing on the activation of energy metabolism. In this study, C. monspeliensis was investigated as the food resources by activation of energy metabolism in human intestinal epithelial cells. C. monspeliensis extract showed high antioxidant ability. In addition, the promotion of metabolites of glycolysis and TCA cycle was induced by C. monspeliensis treatment. These results suggest that C. monspeliensis extract has an ability to enhance the energy metabolism in human intestinal cells.

  2. Metabolomics Analysis of Cistus monspeliensis Leaf Extract on Energy Metabolism Activation in Human Intestinal Cells

    Directory of Open Access Journals (Sweden)

    Yoichi Shimoda

    2012-01-01

    Full Text Available Energy metabolism is a very important process to improve and maintain health from the point of view of physiology. It is well known that the intracellular ATP production is contributed to energy metabolism in cells. Cistus monspeliensis is widely used as tea, spices, and medical herb; however, it has not been focusing on the activation of energy metabolism. In this study, C. monspeliensis was investigated as the food resources by activation of energy metabolism in human intestinal epithelial cells. C. monspeliensis extract showed high antioxidant ability. In addition, the promotion of metabolites of glycolysis and TCA cycle was induced by C. monspeliensis treatment. These results suggest that C. monspeliensis extract has an ability to enhance the energy metabolism in human intestinal cells.

  3. Diagnosis of edema and inflammation in human intestines using ultrawideband radar

    Science.gov (United States)

    Smith, Sonny; Narayanan, Ram M.; Messaris, Evangelos

    2015-05-01

    Human intestines are vital organs, which are often subjected to chronic issues. In particular, Crohn's disease is a bowel aliment resulting in inflammation along the lining of one's digestive tract. Moreover, such an inflammatory condition causes changes in the thickness of the intestines; and we posit induce changes in the dielectric properties detectable by radar. This detection hinges on the increase in fluid content in the afflicted area, which is described by effective medium approximations (EMA). In this paper, we consider one of the constitutive parameters (i.e. relative permittivity) of different human tissues and introduce a simple numerical, electromagnetic multilayer model. We observe how the increase in water content in one layer can be approximated to predict the effective permittivity of that layer. Moreover, we note trends in how such an accumulation can influence the total effective reflection coefficient of the multiple layers.

  4. Improving access to intestinal stem cells as a step toward intestinal gene transfer.

    Science.gov (United States)

    Sandberg, J W; Lau, C; Jacomino, M; Finegold, M; Henning, S J

    1994-03-01

    In previous studies exploring the intestinal epithelium as a potential site for somatic gene therapy, we concluded that the mucus lining the intestine constitutes a significant barrier to any attempts at gene transfer via the lumenal route. The mucus problem is aggravated by the fact that the epithelial stem cells, which are the logical target for gene transfer, are located deep in the intestinal crypts. The goals of the current study were to develop procedures that would improve accessibility to the intestinal stem cells and which would effect in vivo mucus removal without damaging the underlying epithelium. Initial experiments involved evaluation of the use of distension to improve accessibility to the intestinal crypts and the use of the mucolytic agents dithiothreitol (DTT) and N-acetyl-cysteine (NAC) versus a control solution of phosphate-buffered saline (PBS) for mucus removal. Catheters were inserted in each end of 3-cm terminal ileal segments in anesthetized rats. Two milliliters of agent was instilled into the clamped segment for 2 min, removed, and repeated. Lumenal distension resulted in shortened villi with wider intervillus spacing, thereby improving crypt access. Both NAC and DTT washes removed significant mucus between the villi but failed to reach the crypt lumen. To enhance mucus release from the crypt lumen, pilocarpine was selected due to its cholinergic properties and preferential binding to muscarinic receptors on crypt goblet cells. Pilocarpine given intraperitoneally 30 min prior to the mucolytic or PBS wash resulted in significant eradication of mucus down into the crypt lumen. This effect was still evident 3-4 hr later provided the intestine remained undisturbed.

  5. Metabolism of liriodendrin and syringin by human intestinal bacteria and their relation to in vitro cytotoxicity.

    Science.gov (United States)

    Kim, D H; Lee, K T; Bae, E A; Han, M J; Park, H J

    1999-02-01

    When liriodendrin or syringin was incubated for 24 h with human intestinal bacteria, two metabolites, (+)-syringaresinol-beta-D-glucopyranoside and (+)-syringaresinol, from liriodendrin and one metabolite, synapyl alcohol, from syringin were produced. The metabolic time course of liriodendrin was as follows: at early time, liriodendrin was converted to (+)-syringaresinol-beta-D-glucopyranoside, and then (+)-syringaresinol. The in vitro cytotoxicities of these metabolites, (+)-syringaresinol and synapyl alcohol, were superior to those of liriodendrin and syringin.

  6. Mapping of liver-enriched transcription factors in the human intestine

    Institute of Scientific and Technical Information of China (English)

    Frank; Lehner; Ulf; Kulik; Juergen; Klempnauer; Juergen; Borlak

    2010-01-01

    AIM: To investigate the gene expression pattern of hepatocyte nuclear factor 6 (HNF6) and other liverenriched transcription factors in various segments of the human intestine to better understand the differentiation of the gut epithelium. METHODS: Samples of healthy duodenum and jejunum were obtained from patients with pancreatic cancer whereas ileum and colon was obtained from patients undergoing right or left hemicolectomy or (recto)sigmoid or rectal resection. All surgical specimens were subjected to his...

  7. Associations between common intestinal parasites and bacteria in humans as revealed by qPCR

    DEFF Research Database (Denmark)

    O'Brien Andersen, L.; Karim, A. B.; Roager, Henrik Munch

    2016-01-01

    Several studies have shown associations between groups of intestinal bacterial or specific ratios between bacterial groups and various disease traits. Meanwhile, little is known about interactions and associations between eukaryotic and prokaryotic microorganisms in the human gut. In this work, w...... of Bifidobacterium was subsequently performed, and the relative abundance of these bacteria across the four groups was compared. The relative abundance of Bacteroides in B- D- samples was significantly higher compared with B+ D- and B+ D+ samples (P ...

  8. Ultrastructural study of adhesion of enterotoxigenic Escherichia coli to erythrocytes and human intestinal epithelial cells.

    OpenAIRE

    1984-01-01

    The adhesion to erythrocytes and human intestinal epithelial cells of enterotoxigenic Escherichia coli strains H10407, B2C, and H10407P, expressing colonization factor antigen I (CFA/I), CFA/II, and type 1 fimbriae, respectively, was examined by electron microscopy. CFA and type 1 fimbriae were visualized by negative staining in thin sections after en bloc staining with ruthenium red and by immune labeling with antisera raised against purified fimbriae. By negative and ruthenium red staining,...

  9. Consensus hologram QSAR modeling for the prediction of human intestinal absorption.

    Science.gov (United States)

    Moda, Tiago L; Andricopulo, Adriano D

    2012-04-15

    Consistent in silico models for ADME properties are useful tools in early drug discovery. Here, we report the hologram QSAR modeling of human intestinal absorption using a dataset of 638 compounds with experimental data associated. The final validated models are consistent and robust for the consensus prediction of this important pharmacokinetic property and are suitable for virtual screening applications. Copyright © 2012 Elsevier Ltd. All rights reserved.

  10. Prebiotic effects of almonds and almond skins on intestinal microbiota in healthy adult humans.

    Science.gov (United States)

    Liu, Zhibin; Lin, Xiuchun; Huang, Guangwei; Zhang, Wen; Rao, Pingfan; Ni, Li

    2014-04-01

    Almonds and almond skins are rich in fiber and other components that have potential prebiotic properties. In this study we investigated the prebiotic effects of almond and almond skin intake in healthy humans. A total of 48 healthy adult volunteers consumed a daily dose of roasted almonds (56 g), almond skins (10 g), or commercial fructooligosaccharides (8 g) (as positive control) for 6 weeks. Fecal samples were collected at defined time points and analyzed for microbiota composition and selected indicators of microbial activity. Different strains of intestinal bacteria had varying degrees of growth sensitivity to almonds or almond skins. Significant increases in the populations of Bifidobacterium spp. and Lactobacillus spp. were observed in fecal samples as a consequence of almond or almond skin supplementation. However, the populations of Escherichia coli did not change significantly, while the growth of the pathogen Clostridum perfringens was significantly repressed. Modification of the intestinal microbiota composition induced changes in bacterial enzyme activities, specifically a significant increase in fecal β-galactosidase activity and decreases in fecal β-glucuronidase, nitroreductase and azoreductase activities. Our observations suggest that almond and almond skin ingestion may lead to an improvement in the intestinal microbiota profile and a modification of the intestinal bacterial activities, which would induce the promotion of health beneficial factors and the inhibition of harmful factors. Thus we believe that almonds and almond skins possess potential prebiotic properties.

  11. Intestinal flora of animal models of human diseases as an environmental factor.

    Science.gov (United States)

    Itoh, K; Narushima, S

    2005-03-01

    Genetically-engineered animals are known to be useful in clarifying the functions of many genes and as animal models for human diseases. However, it has been widely reported that pathophysiology is not expressed in these animals when they become germfree or SPF animals, i.e., the pathophysiology is not the result of genes alone and a combination of gene function and intestinal flora as an environmental factor are necessary. It is important to determine the roles of each of these two factors by pathophysiological analysis. Gnotobiotic mice were produced by establishment of specified bacterial species in germfree animals to form the intestinal flora of SPF animals and they were placed in barrier facilities. Measures have been taken against infections by bacteria such as Pseudomonas aeruginosa and Enterobacter cloacae. In addition, gnotobiotic mice with a highly normal physiology are required. Analysis of the effects of each bacterial species and combinations of bacteria on in vivo functions, i.e., the cross-talk between the host and intestinal flora, is essential in the creation of better laboratory animals. Monitoring of the intestinal flora, a key factor in the colonies produced, is a topic for future research.

  12. Pic, an autotransporter protein secreted by different pathogens in the Enterobacteriaceae family, is a potent mucus secretagogue.

    Science.gov (United States)

    Navarro-Garcia, Fernando; Gutierrez-Jimenez, Javier; Garcia-Tovar, Carlos; Castro, Luis A; Salazar-Gonzalez, Hector; Cordova, Vanessa

    2010-10-01

    A hallmark of enteroaggregative Escherichia coli (EAEC) infection is a formation of biofilm, which comprises a mucus layer with immersed bacteria in the intestines of patients. While studying the mucinolytic activity of Pic in an in vivo system, rat ileal loops, we surprisingly found that EAEC induced hypersecretion of mucus, which was accompanied by an increase in the number of mucus-containing goblet cells. Interestingly, an isogenic pic mutant (EAEC Δpic) was unable to cause this mucus hypersecretion. Furthermore, purified Pic was also able to induce intestinal mucus hypersecretion, and this effect was abolished when Pic was heat denatured. Site-directed mutagenesis of the serine protease catalytic residue of Pic showed that, unlike the mucinolytic activity, secretagogue activity did not depend on this catalytic serine protease motif. Other pathogens harboring the pic gene, such as Shigella flexneri and uropathogenic E. coli (UPEC), also showed results similar to those for EAEC, and construction of isogenic pic mutants of S. flexneri and UPEC confirmed this secretagogue activity. Thus, Pic mucinase is responsible for one of the pathophysiologic features of the diarrhea mediated by EAEC and the mucoid diarrhea induced by S. flexneri.

  13. Novel mucus-penetrating liposomes as a potential oral drug delivery system: preparation, in vitro characterization, and enhanced cellular uptake

    Directory of Open Access Journals (Sweden)

    Li X

    2011-12-01

    Full Text Available Xiuying Li1, Dan Chen1, Chaoyi Le2, Chunliu Zhu1, Yong Gan1, Lars Hovgaard3, Mingshi Yang41Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China; 2University of Toronto Mississauga Campus, Ontario, Canada; 3Oral Formulation Development, Novo Nordisk A/S, Maalov; 4Department of Pharmaceutics and Analytical Chemistry, University of Copenhagen, Copenhagen, DenmarkBackground: The aim of this study was to investigate the intestinal mucus-penetrating properties and intestinal cellular uptake of two types of liposomes modified by Pluronic F127 (PF127.Methods: The two types of liposomes, ie, PF127-inlaid liposomes and PF127-adsorbed liposomes, were prepared by a thin-film hydration method followed by extrusion, in which coumarin 6 was loaded as a fluorescence marker. A modified Franz diffusion cell mounted with the intestinal mucus of rats was used to study the diffusion characteristics of the two types of PF127 liposomes. Cell uptake studies were conducted in Caco-2 cells and analyzed using confocal laser scanning microcopy as well as flow cytometry.Results: The diffusion efficiency of the two types of PF127-modified liposomes through intestinal rat mucus was 5–7-fold higher than that of unmodified liposomes. Compared with unmodified liposomes, PF127-inlaid liposomes showed significantly higher cellular uptake of courmarin 6. PF127-adsorbed liposomes showed a lower cellular uptake. Moreover, and interestingly, the two types of PF127-modified liposomes showed different cellular uptake mechanisms in Caco-2 cells.Conclusion: PF127-inlaid liposomes with improved intestinal mucus-penetrating ability and enhanced cellular uptake might be a potential carrier candidate for oral drug delivery.Keywords: Pluronic F127, mucus-penetrating, particles, liposomes, oral drug delivery

  14. Human amniotic membrane as an intestinal patch for neomucosal growth in the rabbit model.

    Science.gov (United States)

    Barlas, M; Gökçora, H; Erekul, S; Dindar, H; Yücesan, S

    1992-05-01

    This experiment was carried out as a preliminary study, an attempt to grow new intestinal mucosa on human amniotic membrane in the terminal ileum in 37 rabbits. After ketamin sulfate anesthesia at laparatomy, 5-cm ileal defects were patched with human amniotic membrane (5 x 2 cm). These patched intestines were investigated on the first postoperative day and the 2nd, 5th, 10th, and 20th weeks corresponding to 4, 5, 5, 10, and 10 rabbits, respectively. Only three rabbits died in the early postoperative period. There was no evidence of intestinal obstruction or dilatation with barium meal. Microscopically, the neomucosa consisted of a thin layer of columnar epithelial cells at 2 weeks with more maturity of the villi and less irregularity and branching by 20 weeks. All patches were covered with neomucosa commencing at 2 weeks and covering the whole patch area by 20 weeks. This technique's advantages are the large size and the ease of the availability of the human amniotic membrane for neonates at risk without jeopardizing the neonates tissues. It is hoped that this method might be considered when neonatal material is scarce.

  15. The action of berry phenolics against human intestinal pathogens.

    Science.gov (United States)

    Puupponen-Pimiä, Riitta; Nohynek, Liisa; Alakomi, Hanna-Leena; Oksman-Caldentey, Kirsi-Marja

    2005-01-01

    Phenolic compounds present in berries selectively inhibit the growth of human gastrointestinal pathogens. Especially cranberry, cloudberry, raspberry, strawberry and bilberry possess clear antimicrobial effects against e.g. salmonella and staphylococcus. Complex phenolic polymers, such as ellagitannins, are strong antibacterial agents present in cloudberry, raspberry and strawberry. Berry phenolics seem to affect the growth of different bacterial species with different mechanisms. Adherence of bacteria to epithelial surfaces is a prerequisite for colonization and infection of many pathogens. Antimicrobial activity of berries may also be related to anti-adherence activity of the berries. Utilization of enzymes in berry processing increases the amount of phenolics and antimicrobial activity of the berry products. Antimicrobial berry compounds are likely to have many important applications in the future as natural antimicrobial agents for food industry as well as for medicine.

  16. Prediction of human drug clearance by multiple metabolic pathways: integration of hepatic and intestinal microsomal and cytosolic data.

    Science.gov (United States)

    Cubitt, Helen E; Houston, J Brian; Galetin, Aleksandra

    2011-05-01

    The current study assesses hepatic and intestinal glucuronidation, sulfation, and cytochrome P450 (P450) metabolism of raloxifene, quercetin, salbutamol, and troglitazone using different in vitro systems. The fraction metabolized by conjugation and P450 metabolism was estimated in liver and intestine, and the importance of multiple metabolic pathways on accuracy of clearance prediction was assessed. In vitro intrinsic sulfation clearance (CL(int, SULT)) was determined in human intestinal and hepatic cytosol and compared with hepatic and intestinal microsomal glucuronidation (CL(int, UGT)) and P450 clearance (CL(int, CYP)) expressed per gram of tissue. Hepatic and intestinal cytosolic scaling factors of 80.7 mg/g liver and 18 mg/g intestine were estimated from published data. Scaled CL(int, SULT) ranged between 0.7 and 11.4 ml · min(-1) · g(-1) liver and 0.1 and 3.3 ml · min(-1) · g(-1) intestine (salbutamol and quercetin were the extremes). Salbutamol was the only compound with a high extent of sulfation (51 and 28% of total CL(int) for liver and intestine, respectively) and also significant renal clearance (26-57% of observed plasma clearance). In contrast, the clearance of quercetin was largely accounted for by glucuronidation. Drugs metabolized by multiple pathways (raloxifene and troglitazone) demonstrated improved prediction of intravenous clearance using data from all hepatic pathways (44-86% of observed clearance) compared with predictions based only on the primary pathway (22-36%). The assumption of no intestinal first pass resulted in underprediction of oral clearance for raloxifene, troglitazone, and quercetin (3-22% of observed, respectively). Accounting for the intestinal contribution to oral clearance via estimated intestinal availability improved prediction accuracy for raloxifene and troglitazone (within 2.5-fold of observed). Current findings emphasize the importance of both hepatic and intestinal conjugation for in vitro-in vivo extrapolation

  17. Enterocyte shedding and epithelial lining repair following ischemia of the human small intestine attenuate inflammation.

    Directory of Open Access Journals (Sweden)

    Robert A Matthijsen

    Full Text Available BACKGROUND: Recently, we observed that small-intestinal ischemia and reperfusion was found to entail a rapid loss of apoptotic and necrotic cells. This study was conducted to investigate whether the observed shedding of ischemically damaged epithelial cells affects IR induced inflammation in the human small gut. METHODS AND FINDINGS: Using a newly developed IR model of the human small intestine, the inflammatory response was studied on cellular, protein and mRNA level. Thirty patients were consecutively included. Part of the jejunum was subjected to 30 minutes of ischemia and variable reperfusion periods (mean reperfusion time 120 (+/-11 minutes. Ethical approval and informed consent were obtained. Increased plasma intestinal fatty acid binding protein (I-FABP levels indicated loss in epithelial cell integrity in response to ischemia and reperfusion (p<0.001 vs healthy. HIF-1alpha gene expression doubled (p = 0.02 and C3 gene expression increased 4-fold (p = 0.01 over the course of IR. Gut barrier failure, assessed as LPS concentration in small bowel venous effluent blood, was not observed (p = 0.18. Additionally, mRNA expression of HO-1, IL-6, IL-8 did not alter. No increased expression of endothelial adhesion molecules, TNFalpha release, increased numbers of inflammatory cells (p = 0.71 or complement activation, assessed as activated C3 (p = 0.14, were detected in the reperfused tissue. CONCLUSIONS: In the human small intestine, thirty minutes of ischemia followed by up to 4 hours of reperfusion, does not seem to lead to an explicit inflammatory response. This may be explained by a unique mechanism of shedding of damaged enterocytes, reported for the first time by our group.

  18. Human intestinal microbiota and diseases%人体肠道细菌群落与疾病

    Institute of Scientific and Technical Information of China (English)

    翁幸鐾; 糜祖煌

    2011-01-01

    肠道定植有100万亿细菌,这占到了人体细菌总量的绝大多数.一旦肠道菌群失调,就会产生一系列疾病.本文介绍了人体肠道细菌群落异常与5种肠道疾病和5种肠道外疾病的关系,并推荐用益生菌和益生素来治疗人体肠道细菌群落异常.为了解人体肠道细菌群落和人体健康的关系,美国国立卫生研究院已启动了人类微生物组计划,欧洲委员会也正在资助人类肠道宏基因组学项目,而中国在此项目中亦取得了可喜进步.基于肠道宏基因组的个体化医疗时代已不再遥远.%Gut homes 100 trillion microorganisms-the vast majority of our complement of microbes.Shifts in the microbial species that reside in our intestines have been associated with a long list of pathologies.The review introduces a strong correlation between disrupted microbial composition and 5 kinds of gastrointestinal problems as well as 5 kinds of extra-gastrointestinal problems, and recommends probiotics and prebiotics to treat microbiota-associated illness.In order to find out the relationship between human intestinal microbiota and diseases, the National Institutes of Health launched the Human Microbiome Project at the end of 2007, and the European Commission is funding a related effort, called Metagenomics of the Human Intestinal Tract, in which China makes delightful progress.In sum, individual therapy based on intestinal metagenomics is coming.

  19. Ricin crosses polarized human intestinal cells and intestines of ricin-gavaged mice without evident damage and then disseminates to mouse kidneys.

    Directory of Open Access Journals (Sweden)

    Alyssa D Flora

    Full Text Available Ricin is a potent toxin found in the beans of Ricinus communis and is often lethal for animals and humans when aerosolized or injected and causes significant morbidity and occasional death when ingested. Ricin has been proposed as a bioweapon because of its lethal properties, environmental stability, and accessibility. In oral intoxication, the process by which the toxin transits across intestinal mucosa is not completely understood. To address this question, we assessed the impact of ricin on the gastrointestinal tract and organs of mice after dissemination of toxin from the gut. We first showed that ricin adhered in a specific pattern to human small bowel intestinal sections, the site within the mouse gut in which a variable degree of damage has been reported by others. We then monitored the movement of ricin across polarized human HCT-8 intestinal monolayers grown in transwell inserts and in HCT-8 cell organoids. We observed that, in both systems, ricin trafficked through the cells without apparent damage until 24 hours post intoxication. We delivered a lethal dose of purified fluorescently-labeled ricin to mice by oral gavage and followed transit of the toxin from the gastrointestinal tracts to the internal organs by in vivo imaging of whole animals over time and ex vivo imaging of organs at various time points. In addition, we harvested organs from unlabeled ricin-gavaged mice and assessed them for the presence of ricin and for histological damage. Finally, we compared serum chemistry values from buffer-treated versus ricin-intoxicated animals. We conclude that ricin transverses human intestinal cells and mouse intestinal cells in situ prior to any indication of enterocyte damage and that ricin rapidly reaches the kidneys of intoxicated mice. We also propose that mice intoxicated orally with ricin likely die from distributive shock.

  20. Ricin crosses polarized human intestinal cells and intestines of ricin-gavaged mice without evident damage and then disseminates to mouse kidneys.

    Science.gov (United States)

    Flora, Alyssa D; Teel, Louise D; Smith, Mark A; Sinclair, James F; Melton-Celsa, Angela R; O'Brien, Alison D

    2013-01-01

    Ricin is a potent toxin found in the beans of Ricinus communis and is often lethal for animals and humans when aerosolized or injected and causes significant morbidity and occasional death when ingested. Ricin has been proposed as a bioweapon because of its lethal properties, environmental stability, and accessibility. In oral intoxication, the process by which the toxin transits across intestinal mucosa is not completely understood. To address this question, we assessed the impact of ricin on the gastrointestinal tract and organs of mice after dissemination of toxin from the gut. We first showed that ricin adhered in a specific pattern to human small bowel intestinal sections, the site within the mouse gut in which a variable degree of damage has been reported by others. We then monitored the movement of ricin across polarized human HCT-8 intestinal monolayers grown in transwell inserts and in HCT-8 cell organoids. We observed that, in both systems, ricin trafficked through the cells without apparent damage until 24 hours post intoxication. We delivered a lethal dose of purified fluorescently-labeled ricin to mice by oral gavage and followed transit of the toxin from the gastrointestinal tracts to the internal organs by in vivo imaging of whole animals over time and ex vivo imaging of organs at various time points. In addition, we harvested organs from unlabeled ricin-gavaged mice and assessed them for the presence of ricin and for histological damage. Finally, we compared serum chemistry values from buffer-treated versus ricin-intoxicated animals. We conclude that ricin transverses human intestinal cells and mouse intestinal cells in situ prior to any indication of enterocyte damage and that ricin rapidly reaches the kidneys of intoxicated mice. We also propose that mice intoxicated orally with ricin likely die from distributive shock.

  1. Hot spices influence permeability of human intestinal epithelial monolayers.

    Science.gov (United States)

    Jensen-Jarolim, E; Gajdzik, L; Haberl, I; Kraft, D; Scheiner, O; Graf, J

    1998-03-01

    Indirect evidence suggests that hot spices may interact with epithelial cells of the gastrointestinal tract to modulate their transport properties. Using HCT-8 cells, a cell line from a human ileocoecal carcinoma, we studied the effects of spices on transepithelial electrical resistance (TER), permeability for fluorescein isothiocyanate (FITC)-labeled dextrans with graded molecular weight, and morphological alterations of tight junctions by immunofluorescence using an anti-ZO-1 antibody, a marker for tight junction integrity. Two different reactivity patterns were observed: paprika and cayenne pepper significantly decreased the TER and increased permeability for 10-, 20- and 40-kDa dextrans but not for -70 kDa dextrans. Simultaneously, tight junctions exhibited a discontinuous pattern. Applying extracts from black or green pepper, bay leaf or nutmeg increased the TER and macromolecular permeability remained low. Immunofluorescence ZO-1 staining was preserved. In accordance with the above findings, capsaicin transiently reduced resistance and piperine increased resistance, making them candidates for causing the effects seen with crude spice extracts. The observation that Solanaceae spices (paprika, cayenne pepper) increase permeability for ions and macromolecules might be of pathophysiological importance, particularly with respect to food allergy and intolerance.

  2. Enterocyte shedding and epithelial lining repair following ischemia of the human small intestine attenuate inflammation.

    Science.gov (United States)

    Matthijsen, Robert A; Derikx, Joep P M; Kuipers, Dian; van Dam, Ronald M; Dejong, Cornelis H C; Buurman, Wim A

    2009-09-15

    Recently, we observed that small-intestinal ischemia and reperfusion was found to entail a rapid loss of apoptotic and necrotic cells. This study was conducted to investigate whether the observed shedding of ischemically damaged epithelial cells affects IR induced inflammation in the human small gut. Using a newly developed IR model of the human small intestine, the inflammatory response was studied on cellular, protein and mRNA level. Thirty patients were consecutively included. Part of the jejunum was subjected to 30 minutes of ischemia and variable reperfusion periods (mean reperfusion time 120 (+/-11) minutes). Ethical approval and informed consent were obtained. Increased plasma intestinal fatty acid binding protein (I-FABP) levels indicated loss in epithelial cell integrity in response to ischemia and reperfusion (pintestine, thirty minutes of ischemia followed by up to 4 hours of reperfusion, does not seem to lead to an explicit inflammatory response. This may be explained by a unique mechanism of shedding of damaged enterocytes, reported for the first time by our group.

  3. Otilonium bromide inhibits calcium entry through L-type calcium channels in human intestinal smooth muscle.

    Science.gov (United States)

    Strege, P R; Evangelista, S; Lyford, G L; Sarr, M G; Farrugia, G

    2004-04-01

    Otilonium bromide (OB) is used as an intestinal antispasmodic. The mechanism of action of OB is not completely understood. As Ca(2+) entry into intestinal smooth muscle is required to trigger contractile activity, our hypothesis was that OB blocked Ca(2+) entry through L-type Ca(2+) channels. Our aim was to determine the effects of OB on Ca(2+), Na(+) and K(+) ion channels in human jejunal circular smooth muscle cells and on L-type Ca(2+) channels expressed heterologously in HEK293 cells. Whole cell currents were recorded using standard patch clamp techniques. Otilonium bromide (0.09-9 micromol L(-1)) was used as this reproduced clinical intracellular concentrations. In human circular smooth muscle cells, OB inhibited L-type Ca(2+) current by 25% at 0.9 micromol L(-1) and 90% at 9 micromol L(-1). Otilonium bromide had no effect on Na(+) or K(+) currents. In HEK293 cells, 1 micromol L(-1) OB significantly inhibited the expressed L-type Ca(2+) channels. Truncation of the alpha(1C) subunit C and N termini did not block the inhibitory effects of OB. Otilonium bromide inhibited Ca(2+) entry through L-type Ca(2+) at concentrations similar to intestinal tissue levels. This effect may underlie the observed muscle relaxant effects of the drug.

  4. Effects of Acute Hyperglucagonemia on Hepatic and Intestinal Lipoprotein Production and Clearance in Healthy Humans

    Science.gov (United States)

    Xiao, Changting; Pavlic, Mirjana; Szeto, Linda; Patterson, Bruce W.; Lewis, Gary F.

    2011-01-01

    OBJECTIVE The metabolism of hepatic- and intestinally derived lipoproteins is regulated in a complex fashion by nutrients, hormones, and neurologic and other factors. Recent studies in animal models suggest an important role for glucagon acting via the glucagon receptor in regulating hepatic triglyceride (TG) secretion. Here we examined the direct effects of glucagon on regulation of hepatic and intestinal lipoprotein metabolism in humans. RESEARCH DESIGN AND METHODS Eight healthy men underwent two studies each, in random order, 4–6 weeks apart in which de novo lipogenesis, kinetics of larger VLDL1 TG, and kinetics of VLDL1 and smaller VLDL2 apolipoprotein (apo)B100 and B48 were studied using established stable isotope enrichment methods. Subjects were studied in the constant fed state under conditions of a pancreatic clamp (with infusion of somatostatin, insulin, and growth hormone) at either basal glucagon (BG study, 64.5 ± 2.1 pg/mL) or hyperglucagonemia (high glucagon [HG] study, 183.2 ± 5.1 pg/mL). RESULTS There were no significant differences in plasma concentration of VLDL1 or VLDL2 TG, apoB100 or apoB48 between BG and HG studies. There was, however, lower (P lipoprotein metabolism. CONCLUSIONS Glucagon acutely regulates hepatic but not intestinal lipoprotein particle metabolism in humans both by decreasing hepatic lipoprotein particle production as well as by inhibiting particle clearance, with no net effect on particle concentration. PMID:20980459

  5. Comprehensive Survey of Intestinal Microbiota Changes in Offspring of Human Microbiota-Associated Mice

    Science.gov (United States)

    von Klitzing, Eliane; Öz, Fulya; Ekmekciu, Ira; Escher, Ulrike; Bereswill, Stefan; Heimesaat, Markus M.

    2017-01-01

    Secondary abiotic mice generated by broad-spectrum antibiotic treatment provide a valuable tool for association studies with microbiota derived from different vertebrate hosts. We here generated human microbiota-associated (hma) mice by human fecal microbiota transplantation of secondary abiotic mice and performed a comprehensive survey of the intestinal microbiota dynamics in offspring of hma mice over 18 weeks following weaning as compared to their mothers applying both cultural and molecular methods. Mice were maintained under standard hygienic conditions with open cages, handled under aseptic conditions, and fed autoclaved chow and water. Within 1 week post weaning, fecal loads of commensal enterobacteria and enterococci had decreased, whereas obligate anaerobic bacteria such as Bacteroides/Prevotella species and clostridia were stably colonizing the intestines of hma offspring at high loads. Lactobacilli numbers were successively increasing until 18 weeks post weaning in both hma offspring and mothers, whereas by then, bifidobacteria were virtually undetectable in the former only. Interestingly, fecal lactobacilli and bifidobacteria were higher in mothers as compared to their offspring at 5 and 18 weeks post weaning. We conclude that the intestinal microbiota composition changes in offspring of hma mice, but also their mothers over time particularly affecting aerobic and microaerobic species. PMID:28386472

  6. Anthocyanin Absorption and Metabolism by Human Intestinal Caco-2 Cells--A Review.

    Science.gov (United States)

    Kamiloglu, Senem; Capanoglu, Esra; Grootaert, Charlotte; Van Camp, John

    2015-09-08

    Anthocyanins from different plant sources have been shown to possess health beneficial effects against a number of chronic diseases. To obtain any influence in a specific tissue or organ, these bioactive compounds must be bioavailable, i.e., effectively absorbed from the gut into the circulation and transferred to the appropriate location within the body while still maintaining their bioactivity. One of the key factors affecting the bioavailability of anthocyanins is their transport through the gut epithelium. The Caco-2 cell line, a human intestinal epithelial cell model derived from a colon carcinoma, has been proven to be a good alternative to animal studies for predicting intestinal absorption of anthocyanins. Studies investigating anthocyanin absorption by Caco-2 cells report very low absorption of these compounds. However, the bioavailability of anthocyanins may be underestimated since the metabolites formed in the course of digestion could be responsible for the health benefits associated with anthocyanins. In this review, we critically discuss recent findings reported on the anthocyanin absorption and metabolism by human intestinal Caco-2 cells.

  7. Anthocyanin Absorption and Metabolism by Human Intestinal Caco-2 Cells—A Review

    Directory of Open Access Journals (Sweden)

    Senem Kamiloglu

    2015-09-01

    Full Text Available Anthocyanins from different plant sources have been shown to possess health beneficial effects against a number of chronic diseases. To obtain any influence in a specific tissue or organ, these bioactive compounds must be bioavailable, i.e., effectively absorbed from the gut into the circulation and transferred to the appropriate location within the body while still maintaining their bioactivity. One of the key factors affecting the bioavailability of anthocyanins is their transport through the gut epithelium. The Caco-2 cell line, a human intestinal epithelial cell model derived from a colon carcinoma, has been proven to be a good alternative to animal studies for predicting intestinal absorption of anthocyanins. Studies investigating anthocyanin absorption by Caco-2 cells report very low absorption of these compounds. However, the bioavailability of anthocyanins may be underestimated since the metabolites formed in the course of digestion could be responsible for the health benefits associated with anthocyanins. In this review, we critically discuss recent findings reported on the anthocyanin absorption and metabolism by human intestinal Caco-2 cells.

  8. Activation of intestinal epithelial Stat3 orchestrates tissue defense during gastrointestinal infection.

    Directory of Open Access Journals (Sweden)

    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.

  9. E durans strain M4-5 isolated from human colonic flora attenuates intestinal inflammation

    DEFF Research Database (Denmark)

    Avram-Hananel, Liraz; Stock, Julia; Parlesak, Alexandr;

    2010-01-01

    effects, mediated by regulation of pro- and anti-inflammatory immune factors as well as preservation of intestine epithelial integrity, suggesting that this novel anti-inflammatory bacterium may be preferentially a useful prophylactic treatment to avoid inflammatory bowel disease.......PURPOSE: The aim of this study was to evaluate in vitro and in vivo effects of a unique high-butyrate-producing bacterial strain from human colonic flora, Enterococcus durans, in prevention and treatment of intestinal inflammation. METHODS: A compartmentalized Caco-2/leukocyte coculture model...... was used to examine the in vitro effects of E durans and its metabolite butyrate on basal and Escherichia coli-stimulated secretion of proinflammatory immune factors (IL-8, IL-6, and TNF-α) and the anti-inflammatory cytokine IL-10. A murine model of dextran sodium sulfate-induced colitis was used...

  10. Vasoactive Intestinal Peptide Inhibits Human Small-Cell Lung Cancer Proliferation in vitro and in vivo

    Science.gov (United States)

    Maruno, Kaname; Absood, Afaf; Said, Sami I.

    1998-11-01

    Small-cell lung carcinoma (SCLC) is an aggressive, rapidly growing and metastasizing, and highly fatal neoplasm. We report that vasoactive intestinal peptide inhibits the proliferation of SCLC cells in culture and dramatically suppresses the growth of SCLC tumor-cell implants in athymic nude mice. In both cases, the inhibition was mediated apparently by a cAMP-dependent mechanism, because the inhibition was enhanced by the adenylate cyclase activator forskolin and the phosphodiesterase inhibitor 3-isobutyl-1-methylxanthine in proportion to increases in intracellular cAMP levels, and the inhibition was abolished by selective inhibition of cAMP-dependent protein kinase. If confirmed in clinical trials, this antiproliferative action of vasoactive intestinal peptide may offer a new and promising means of suppressing SCLC in human subjects, without the toxic side effects of chemotherapeutic agents.

  11. Immunomodulatory properties of Streptococcus and Veillonella isolates from the human small intestine microbiota.

    Directory of Open Access Journals (Sweden)

    Bartholomeus van den Bogert

    Full Text Available The human small intestine is a key site for interactions between the intestinal microbiota and the mucosal immune system. Here we investigated the immunomodulatory properties of representative species of commonly dominant small-intestinal microbial communities, including six streptococcal strains (four Streptococcus salivarius, one S. equinus, one S. parasanguinis one Veillonella parvula strain, one Enterococcus gallinarum strain, and Lactobacillus plantarum WCFS1 as a bench mark strain on human monocyte-derived dendritic cells. The different streptococci induced varying levels of the cytokines IL-8, TNF-α, and IL-12p70, while the V. parvula strain showed a strong capacity to induce IL-6. E. gallinarum strain was a potent inducer of cytokines and TLR2/6 signalling. As Streptococcus and Veillonella can potentially interact metabolically and frequently co-occur in ecosystems, immunomodulation by pair-wise combinations of strains were also tested for their combined immunomodulatory properties. Strain combinations induced cytokine responses in dendritic cells that differed from what might be expected on the basis of the results obtained with the individual strains. A combination of (some streptococci with Veillonella appeared to negate IL-12p70 production, while augmenting IL-8, IL-6, IL-10, and TNF-α responses. This suggests that immunomodulation data obtained in vitro with individual strains are unlikely to adequately represent immune responses to mixtures of gut microbiota communities in vivo. Nevertheless, analysing the immune responses of strains representing the dominant species in the intestine may help to identify immunomodulatory mechanisms that influence immune homeostasis.

  12. Commensal Streptococcus salivarius Modulates PPARγ Transcriptional Activity in Human Intestinal Epithelial Cells.

    Science.gov (United States)

    Couvigny, Benoît; de Wouters, Tomas; Kaci, Ghalia; Jacouton, Elsa; Delorme, Christine; Doré, Joël; Renault, Pierre; Blottière, Hervé M; Guédon, Eric; Lapaque, Nicolas

    2015-01-01

    The impact of commensal bacteria in eukaryotic transcriptional regulation has increasingly been demonstrated over the last decades. A multitude of studies have shown direct effects of commensal bacteria from local transcriptional activity to systemic impact. The commensal bacterium Streptococcus salivarius is one of the early bacteria colonizing the oral and gut mucosal surfaces. It has been shown to down-regulate nuclear transcription factor (NF-кB) in human intestinal cells, a central regulator of the host mucosal immune system response to the microbiota. In order to evaluate its impact on a further important transcription factor shown to link metabolism and inflammation in the intestine, namely PPARγ (peroxisome proliferator-activated receptor), we used human intestinal epithelial cell-lines engineered to monitor PPARγ transcriptional activity in response to a wide range of S. salivarius strains. We demonstrated that different strains from this bacterial group share the property to inhibit PPARγ activation independently of the ligand used. First attempts to identify the nature of the active compounds showed that it is a low-molecular-weight, DNase-, proteases- and heat-resistant metabolite secreted by S. salivarius strains. Among PPARγ-targeted metabolic genes, I-FABP and Angptl4 expression levels were dramatically reduced in intestinal epithelial cells exposed to S. salivarius supernatant. Both gene products modulate lipid accumulation in cells and down-regulating their expression might consequently affect host health. Our study shows that species belonging to the salivarius group of streptococci impact both host inflammatory and metabolic regulation suggesting a possible role in the host homeostasis and health.

  13. Lysophosphatidylcholine enhances carotenoid uptake from mixed micelles by Caco-2 human intestinal cells.

    Science.gov (United States)

    Sugawara, T; Kushiro, M; Zhang, H; Nara, E; Ono, H; Nagao, A

    2001-11-01

    Despite the interest in the beneficial roles of dietary carotenoids in human health, little is known about their solubilization from foods to mixed bile micelles during digestion and the intestinal uptake from the micelles. We investigated the absorption of carotenoids solubilized in mixed micelles by differentiated Caco-2 human intestinal cells, which is a useful model for studying the absorption of dietary compounds by intestinal cells. The micelles were composed of 1 micromol/L carotenoids, 2 mmol/L sodium taurocholate, 100 micromol/L monoacylglycerol, 33.3 micromol/L fatty acid and phospholipid (0-200 micromol/L). The phospholipid content of micelles had profound effects on the cellular uptake of carotenoids. Uptake of micellar beta-carotene and lutein was greatly suppressed by phosphatidylcholine (PC) in a dose-dependent manner, whereas lysophosphatidylcholine (lysoPC), the lipolysis product of PC by phospholipase A2 (PLA2), markedly enhanced both beta-carotene and lutein uptake. The addition of PLA2 from porcine pancreas to the medium also enhanced the uptake of carotenoids from micelles containing PC. Caco-2 cells could take up 15 dietary carotenoids, including epoxy carotenoids, such as violaxanthin, neoxanthin and fucoxanthin, from micellar carotenoids, and the uptakes showed a linear correlation with their lipophilicity, defined as the distribution coefficient in 1-octanol/water (log P(ow)). These results suggest that pancreatic PLA2 and lysoPC are important in regulating the absorption of carotenoids in the digestive tract and support a simple diffusion mechanism for carotenoid absorption by the intestinal epithelium.

  14. Commensal Streptococcus salivarius Modulates PPARγ Transcriptional Activity in Human Intestinal Epithelial Cells.

    Directory of Open Access Journals (Sweden)

    Benoît Couvigny

    Full Text Available The impact of commensal bacteria in eukaryotic transcriptional regulation has increasingly been demonstrated over the last decades. A multitude of studies have shown direct effects of commensal bacteria from local transcriptional activity to systemic impact. The commensal bacterium Streptococcus salivarius is one of the early bacteria colonizing the oral and gut mucosal surfaces. It has been shown to down-regulate nuclear transcription factor (NF-кB in human intestinal cells, a central regulator of the host mucosal immune system response to the microbiota. In order to evaluate its impact on a further important transcription factor shown to link metabolism and inflammation in the intestine, namely PPARγ (peroxisome proliferator-activated receptor, we used human intestinal epithelial cell-lines engineered to monitor PPARγ transcriptional activity in response to a wide range of S. salivarius strains. We demonstrated that different strains from this bacterial group share the property to inhibit PPARγ activation independently of the ligand used. First attempts to identify the nature of the active compounds showed that it is a low-molecular-weight, DNase-, proteases- and heat-resistant metabolite secreted by S. salivarius strains. Among PPARγ-targeted metabolic genes, I-FABP and Angptl4 expression levels were dramatically reduced in intestinal epithelial cells exposed to S. salivarius supernatant. Both gene products modulate lipid accumulation in cells and down-regulating their expression might consequently affect host health. Our study shows that species belonging to the salivarius group of streptococci impact both host inflammatory and metabolic regulation suggesting a possible role in the host homeostasis and health.

  15. Sperm counts in enzymatically liquefied cervical mucus: quantitative validation using donor cervical mucus.

    Science.gov (United States)

    de Agostini, A; Campana, A

    1996-02-01

    The post-coital test evaluates the penetration of spermatozoa into cervical mucus; it relies on subjective measurements and therefore lacks precision. Enzymatic liquefaction of cervical mucus allows sperm concentration to be measured in post-coital test samples, but the reliability of such measurements is not known. Donor cervical mucus was used as a model to test the accuracy and sensitivity of sperm quantification in liquefied cervical mucus. Donor cervical mucus was dissolved by enzymatic treatments in the presence of known numbers of spermatozoa and the recovery of sperm cells was assessed after liquefaction of the samples. Enzymatic treatment of cervical mucus with a combination of bromelin and glycosidases resulted in reliable and fast liquefaction of the samples. The accuracy of sperm concentration measurements was 89 +/- 10% (mean +/- SD, n = 50), and the sensitivity limits were 1 x 10(6) and 0.2 x 10(6) spermatozoa/ml for quantitative concentration measurement and qualitative sperm detection respectively. This study demonstrates that liquefaction of cervical mucus by combined protease and glycosidases allows accurate and sensitive determination of sperm concentration in the sample. Therefore we believe that valuable data can be obtained for sperm concentration and total sperm counts in post-coital tests, that should help to improve the reliability of the post-coital test.

  16. 两种前处理方法对粘液型宫颈HPV分型结果的比较%Comparison of two different pretreatment methods in detecting genotypes of human papillomavirus in cervical epithelium samples with cervical mucus

    Institute of Scientific and Technical Information of China (English)

    伍金华; 郑琰; 高月婵; 陈建勇

    2012-01-01

    Objective To investigate the influence of different pretreatment methods on the detection of genotypes of human papillomavirus in cervical epithelium samples with cervical mucus. Methods The 100 cervical epithelium samples with cervical mucus in gynecology department was pre-treated by traditional method (sodium chloride- concussion method )and proteinase K digestion method. The samples were checked for 21 types HPV by flow through hybridization and gene chip technology. The two different pretreatment methods were used to study the efficiency of HPV DNA extraction and genotyping. Results DNA purification aand concentration afrter extraction were 1.63 ±0.71 and(96.35 ± 13.15)μg/ml while that of HPV-DNA extraction( 105.14 ± 18.65 )μg/ml used by proteinase K digestion method were( 1.80 ± 0.52)and( 105.14 ± 18.65 )μg/ml markedly increased compared with those used by traditional method (P<0.01). PCR inhibitors were detected from 4 samples pre-treated by the traditional method,but no PCR reaction inhibitor was detected from the samples pre-treated by proteinase K digestion method. The rates of positive, single types of infection and multiple infection in the HPV types pre-treated by the traditional method and proteinase K digestion method were 28.0%,23.0%,5.0% and 32.0%, 26.0% ,6.0% .respectively. The value of Kappa was 0.888,showing a high degree of consistency. Conclusion The proteinase K digestion method is suitable for detection of HPV-DNA from cervical epithelium samples with cervical mucus, the pretreatment procedure using proteinase K digestion method is easier to get rid of the PCR reaction inhibitors ,which ensures the quality of HPV DNA. It is applicable in clinical laboratory.%目的 研究2种前处理方法对粘液型标本HPV DNA杂交结果的影响,为进一步提高临床检验质量和改进检测技术提供理论依据.方法 收集100例妇科门诊患者粘液型宫颈脱落细胞标本,分别采用常规方法(生理盐水

  17. Dextran-protamine coated nanostructured lipid carriers as mucus-penetrating nanoparticles for lipophilic drugs.

    Science.gov (United States)

    Beloqui, Ana; Solinís, María Ángeles; des Rieux, Anne; Préat, Véronique; Rodríguez-Gascón, Alicia

    2014-07-01

    The main objectives of the present study were (i) to evaluate the effect of the mucus layer on saquinavir-loaded nanostructured lipid carriers (SQV-NLCs) uptake and (ii) to evaluate the mucopenetrating properties of dextran-protamine (Dex-Prot) coating on NLCs as per SQV permeability enhancement. Three different NLC formulations differing on particle size and surfactant content were obtained and coated with Dex-Prot complexes. SQV permeability was then evaluated across Caco-2 cell monolayers (enterocyte-like model) and Caco-2/HT29-MTX cell monolayers (mucus model). In the Caco-2 monolayers, Dex-Prot-NLCs increased up to 9-fold SQV permeability in comparison to uncoated nanoparticles. In the Caco-2/HT29-MTX monolayers, Dex-Prot-NLCs presenting a surface charge close to neutrality significantly increased SQV permeability. Hence, Dex-Prot complex coating is a promising strategy to ensure successful nanoparticle mucus-penetration, and thus, an efficient nanoparticle oral delivery. To our knowledge, this is the first time that Dex-Prot coating has been described as a nanoparticle muco-penetration enhancer across the intestinal mucus barrier. Copyright © 2014 Elsevier B.V. All rights reserved.

  18. Human intestinal acyl-CoA synthetase 5 is sensitive to the inhibitor triacsin C

    Institute of Scientific and Technical Information of China (English)

    Elke Kaemmerer; Anne Peuscher; Andrea Reinartz; Christian Liedtke; Ralf Weiskirchen; Jürgen Kopitz; Nikolaus Gassler

    2011-01-01

    AIM: To investigate whether human acyl-CoA synthetase 5 (ACSL5) is sensitive to the ACSL inhibitor triacsin C.METHODS: The ACSL isoforms ACSL1 and ACSL5 from rat as well as human ACSL5 were cloned and recombinantly expressed as 6xHis-tagged enzymes. Ni2+-affinity purified recombinant enzymes were assayed at pH 7.5 or pH 9.5 in the presence or absence of triacsin C. In addition, ACSL5 transfected CaCo2 cells and intestinal human mucosa were monitored. ACSL5 expression in cellular systems was verified using Western blot and immunofluorescence.The ACSL assay mix included TrisHCl (pH 7.4), ATP, CoA, EDTA, DTT, MgCl2, [9,10-3H] palmitic acid, and triton X-100. The 200 μL reaction was initiated with the addition of solubilized, purified recombinant proteins or cellular lysates. Reactions were terminated after 10, 30 or 60 min of incubation with Doles medium.RESULTS: Expression of soluble recombinant ACSL pro-teins was found after incubation with isopropyl beta-D-1-thiogalactopyranoside and after ultracentrifugatio these were further purified to near homogeneity with Ni2+-affinity chromatography. Triacsin C selectively and strongly inhibited recombinant human ACSL5 protein at pH 7.5 and pH 9.5, as well as recombinant rat ACSL1 (sensitive control), but not recombinant rat ACSL5 (insensitive control). The IC50 for human ACSL5 was about 10 μmol/L. The inhibitory triacsin C effect was similar for different incubation times (10, 30 and 60 min) and was not modified by the N- or C-terminal location of the 6xHis-tag. In order to evaluate ACSL5 sensitivity to triacsin C in a cellular environment, stable human ACSL5 CaCo2 transfectants and mechanically dissected normal human intestinal mucosa with high physiological expression of ACSL5 were analyzed. In both models, ACSL5 peak activity was found at pH 7.5 and pH 9.5, corresponding to the properties of recombinant human ACSL5 protein. In the presence of triacsin C (25 μmol/L), total ACSL activity was dramatically diminished in

  19. TMEM16A mediates the hypersecretion of mucus induced by Interleukin-13

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Jiachen; Jiang, Youfan; Li, Li; Liu, Yanan; Tang, Hui; Jiang, Depeng, E-mail: depengjiang@163.com

    2015-06-10

    Previous studies showed that the Ca{sup 2+}-activated Cl{sup −} channel (CaCC) was involved in the pathogenesis of mucus hypersecretion induced by Interleukin-13 (IL-13). However, the mechanisms underlying the process were unknown. Recently, transmembrane protein 16A (TMEM16A) was identified as the channel underlying the CaCC current. The aim of the current study was to investigate whether the TMEM16A channel is part of the mechanism underlying IL-13-induced mucus hypersecretion. We observed that both TMEM16A mRNA and protein expression were significantly up-regulated after treatment with IL-13 in human bronchial epithelial 16 (HBE 16) cells, which correlated with an increase in mucus production. Additionally, mucus hypersecretion in rat airways was induced by intratracheal instillation of IL-13 and similar increases were observed in the expression of TMEM16A mRNA and protein in the bronchial epithelium. Niflumic acid (NA), a selective antagonist of CaCC, markedly blocked IL-13-induced mucin (MUC) 5AC mRNA and protein production in vivo and in vitro. Further investigation with HBE16 cells revealed that TMEM16A overexpression clearly promoted mucus production, IκBα phosphorylation, and p65 accumulation in the nucleus. The loss of TMEM16A resulted in inhibition of mucus production, and the TMEM16A-mediated production of MUC5AC was significantly blocked by a nuclear factor-kappa B (NF-κB) inhibitor. Therefore, the TMEM16A channel acts upstream of NF-κB in the regulation of mucus production. This is the first demonstration that the TMEM16A-NF-κB pathway is positively involved in IL-13-induced mucus production, which provides novel insight into the molecular mechanism of mucin overproduction. - Highlights: • TMEM16A acts as downstream events of IL-13 signaling pathway. • Established the link between TMEM16A and mucus hypersecretion. • NF-κB activation might be responsible for TMEM16A mediated mucus secretion.

  20. Prioritization of a plant polysaccharide over a mucus carbohydrate is enforced by a Bacteroides hybrid two-component system.

    Science.gov (United States)

    Lynch, Jonathan B; Sonnenburg, Justin L

    2012-08-01

    Bacteroides is a dominant genus within the intestinal microbiota of healthy humans. Key adaptations of the Bacteroides to the dynamic intestinal ecosystem include a diverse repertoire of genes involved in sensing and processing numerous diet- and host-derived polysaccharides. One such adaptation is the carbohydrate-sensing hybrid two-component system (HTCS) family of signalling sensors, which has been widely expanded within the Bacteroides. Using Bacteroides thetaiotaomicron as a model, we have created a chimeric HTCS consisting of the well-characterized sensing domain of one HTCS, BT1754, and the regulatory domain of another HTCS, BT0366, to explore the regulatory capabilities of these molecules. We found that the BT0366 regulatory region directly binds to and mediates induction of the adjacent polysaccharide utilization locus (PUL) using whole-genome transcriptional profiling after inducing signalling through our chimeric protein. We also found that BT0366 activation simultaneously leads to repression of distal PULs involved in mucus carbohydrate consumption. These results suggest a novel mechanism by which an HTCS enforces a nutrient hierarchy within the Bacteroides via induction and repression of multiple PULs. Thus, hybrid two-component systems provide a mechanism for prioritizing consumption of carbohydrates through simultaneous binding and regulation of multiple polysaccharide utilization loci. © 2012 Blackwell Publishing Ltd.

  1. Mast cell expression of the serotonin1A receptor in guinea pig and human intestine.

    Science.gov (United States)

    Wang, Guo-Du; Wang, Xi-Yu; Zou, Fei; Qu, Meihua; Liu, Sumei; Fei, Guijun; Xia, Yun; Needleman, Bradley J; Mikami, Dean J; Wood, Jackie D

    2013-05-15

    Serotonin [5-hydroxytryptamine (5-HT)] is released from enterochromaffin cells in the mucosa of the small intestine. We tested a hypothesis that elevation of 5-HT in the environment of enteric mast cells might degranulate the mast cells and release mediators that become paracrine signals to the enteric nervous system, spinal afferents, and secretory glands. Western blotting, immunofluorescence, ELISA, and pharmacological analysis were used to study expression of 5-HT receptors by mast cells in the small intestine and action of 5-HT to degranulate the mast cells and release histamine in guinea pig small intestine and segments of human jejunum discarded during Roux-en-Y gastric bypass surgeries. Mast cells in human and guinea pig preparations expressed the 5-HT1A receptor. ELISA detected spontaneous release of histamine in guinea pig and human preparations. The selective 5-HT1A receptor agonist 8-hydroxy-PIPAT evoked release of histamine. A selective 5-HT1A receptor antagonist, WAY-100135, suppressed stimulation of histamine release by 5-HT or 8-hydroxy-PIPAT. Mast cell-stabilizing drugs, doxantrazole and cromolyn sodium, suppressed the release of histamine evoked by 5-HT or 8-hydroxy-PIPAT in guinea pig and human preparations. Our results support the hypothesis that serotonergic degranulation of enteric mast cells and release of preformed mediators, including histamine, are mediated by the 5-HT1A serotonergic receptor. Association of 5-HT with the pathophysiology of functional gastrointestinal disorders (e.g., irritable bowel syndrome) underlies a question of whether selective 5-HT1A receptor antagonists might have therapeutic application in disorders of this nature.

  2. Human intestinal parasites in non-biting synanthropic flies in Ogun State, Nigeria.

    Science.gov (United States)

    Adenusi, Adedotun Adesegun; Adewoga, Thomas O Sunday

    2013-01-01

    Filth-feeding and breeding, non-biting synanthropic flies have been incriminated in the dissemination of human enteropathogens in the environment. This study determined the species of non-biting synanthropic flies associated with four filthy sites in Ilishan, Ogun State, southwest Nigeria, and assessed their potentials for mechanical transmission of human intestinal parasites. 7190 flies identified as Musca domestica (33.94%), Chrysomya megacephala (26.01%), Musca sorbens (23.23%), Lucilia cuprina (8.76%), Calliphora vicina (4.59%), Sarcophaga sp. (2.78%) and Fannia scalaris (0.70%) were examined for human intestinal parasites by the formol-ether concentration and modified Ziehl-Neelsen techniques. Eggs of the following parasites: Ascaris lumbricoides (34.08%), Trichuris trichiura (25.87%), hookworms (20.45%), Taenia sp. (2.36%), Hymenolepis nana (1.11%), Enterobius vermicularis (0.56%), Strongyloides stercoralis (larvae; 3.89%) and cysts of Entamoeba histolytica/dispar (27.26%), Entamoeba coli (22.67%), Giardia lamblia (3.34%) and Cryptosporidium sp. (1.81%) were isolated from the body surfaces and or gut contents of 75.24% of 719 pooled fly batches. The helminths A. lumbricoides and T. trichiura and the protozoans, E. histolytica/dispar and E. coli were the dominant parasites detected, both on body surfaces and in the gut contents of flies. C. megacephala was the highest carrier of parasites (diversity and number). More parasites were isolated from the gut than from body surfaces (P parasites than those from abattoir, garbage or open-air market. Synanthropic fly species identified in this study can be of potential epidemiological importance as mechanical transmitters of human intestinal parasites acquired naturally from filth and carried on their body surfaces and or in the gut, because of their vagility and feeding mechanisms.

  3. Lineage-specific expression of bestrophin-2 and bestrophin-4 in human intestinal epithelial cells.

    Directory of Open Access Journals (Sweden)

    Go Ito

    Full Text Available Intestinal epithelial cells (IECs regulate the absorption and secretion of anions, such as HCO3(- or Cl(-. Bestrophin genes represent a newly identified group of calcium-activated Cl(- channels (CaCCs. Studies have suggested that, among the four human bestrophin-family genes, bestrophin-2 (BEST2 and bestrophin-4 (BEST4 might be expressed within the intestinal tissue. Consistently, a study showed that BEST2 is expressed by human colonic goblet cells. However, their precise expression pattern along the gastrointestinal tract, or the lineage specificity of the cells expressing these genes, remains largely unknown. Here, we show that BEST2 and BEST4 are expressed in vivo, each in a distinct, lineage-specific manner, in human IECs. While BEST2 was expressed exclusively in colonic goblet cells, BEST4 was expressed in the absorptive cells of both the small intestine and the colon. In addition, we found that BEST2 expression is significantly down-regulated in the active lesions of ulcerative colitis, where goblet cells were depleted, suggesting that BEST2 expression is restricted to goblet cells under both normal and pathologic conditions. Consistently, the induction of goblet cell differentiation by a Notch inhibitor, LY411575, significantly up-regulated the expression of not BEST4 but BEST2 in MUC2-positive HT-29 cells. Conversely, the induction of absorptive cell differentiation up-regulated the expression of BEST4 in villin-positive Caco-2 cells. In addition, we found that the up- or down-regulation of Notch activity leads to the preferential expression of either BEST4 or BEST2, respectively, in LS174T cells. These results collectively confirmed that BEST2 and BEST4 could be added to the lineage-specific genes of humans IECs due to their abilities to clearly identify goblet cells of colonic origin and a distinct subset of absorptive cells, respectively.

  4. Occurrence of thraustochytrid fungi in corals and coral mucus

    Digital Repository Service at National Institute of Oceanography (India)

    Raghukumar, S.; Balasubramanian, R.

    Occurrence of thraustochytrid fungi in corals, fresh coral mucus and floating and attached mucus detritus from the Lakshadweep Islands in the Arabian Sea was studied. Corallochytrium limacisporum Raghukumar, Thraustochytrium motivum Goldstein...

  5. Human gut-on-a-chip inhabited by microbial flora that experiences intestinal peristalsis-like motions and flow.

    Science.gov (United States)

    Kim, Hyun Jung; Huh, Dongeun; Hamilton, Geraldine; Ingber, Donald E

    2012-06-21

    Development of an in vitro living cell-based model of the intestine that mimics the mechanical, structural, absorptive, transport and pathophysiological properties of the human gut along with its crucial microbial symbionts could accelerate pharmaceutical development, and potentially replace animal testing. Here, we describe a biomimetic 'human gut-on-a-chip' microdevice composed of two microfluidic channels separated by a porous flexible membrane coated with extracellular matrix (ECM) and lined by human intestinal epithelial (Caco-2) cells that mimics the complex structure and physiology of living intestine. The gut microenvironment is recreated by flowing fluid at a low rate (30 μL h(-1)) producing low shear stress (0.02 dyne cm(-2)) over the microchannels, and by exerting cyclic strain (10%; 0.15 Hz) that mimics physiological peristaltic motions. Under these conditions, a columnar epithelium develops that polarizes rapidly, spontaneously grows into folds that recapitulate the structure of intestinal villi, and forms a high integrity barrier to small molecules that better mimics whole intestine than cells in cultured in static Transwell models. In addition, a normal intestinal microbe (Lactobacillus rhamnosus GG) can be successfully co-cultured for extended periods (>1 week) on the luminal surface of the cultured epithelium without compromising epithelial cell viability, and this actually improves barrier function as previously observed in humans. Thus, this gut-on-a-chip recapitulates multiple dynamic physical and functional features of human intestine that are critical for its function within a controlled microfluidic environment that is amenable for transport, absorption, and toxicity studies, and hence it should have great value for drug testing as well as development of novel intestinal disease models.

  6. Escherichia albertii, a novel human enteropathogen, colonizes rat enterocytes and translocates to extra-intestinal sites

    Science.gov (United States)

    Yamamoto, Denise; Hernandes, Rodrigo T.; Liberatore, Ana Maria A.; Abe, Cecilia M.; de Souza, Rodrigo B.; Romão, Fabiano T.; Sperandio, Vanessa; Koh, Ivan H.

    2017-01-01

    Diarrhea is the second leading cause of death of children up to five years old in the developing countries. Among the etiological diarrheal agents are atypical enteropathogenic Escherichia coli (aEPEC), one of the diarrheagenic E. coli pathotypes that affects children and adults, even in developed countries. Currently, genotypic and biochemical approaches have helped to demonstrate that some strains classified as aEPEC are actually E. albertii, a recently recognized human enteropathogen. Studies on particular strains are necessary to explore their virulence potential in order to further understand the underlying mechanisms of E. albertii infections. Here we demonstrated for the first time that infection of fragments of rat intestinal mucosa is a useful tool to study the initial steps of E. albertii colonization. We also observed that an E. albertii strain can translocate from the intestinal lumen to Mesenteric Lymph Nodes and liver in a rat model. Based on our finding of bacterial translocation, we investigated how E. albertii might cross the intestinal epithelium by performing infections of M-like cells in vitro to identify the potential in vivo translocation route. Altogether, our approaches allowed us to draft a general E. albertii infection route from the colonization till the bacterial spreading in vivo. PMID:28178312

  7. Metabolism of the benzidine-based azo dye Direct Black 38 by human intestinal microbiota

    Energy Technology Data Exchange (ETDEWEB)

    Manning, B.W.; Cerniglia, C.E.; Federle, T.W.

    1985-07-01

    Benzidine-based azo dyes are proven mutagens and have been linked to bladder cancer. Previous studies have indicated that their initial reduction is the result of the azo reductase activity of the intestinal microbiota. Metabolism of the benzidine-based dye Direct Black 38 was examined by using a semicontinuous culture system that simulates the lumen of the human large intestine. The system was inoculated with freshly voided feces, and an active flora was maintained as evidenced by volatile fatty acid and gas production. Within 7 days after exposure to the dye, the following metabolites were isolated and identified by gas chromatography - mass spectrometry: benzidine, 4-aminobiphenyl, monoacetylbenzidine, and acetylaminobiphenyl. Benzidine reached its peak level after 24 h, accounting for 39.1% of the added dye. Its level began to decline, and by day 7 the predominant metabolite was acetylaminobiphenyl, which accounted for 51.1% of the parent compound. Formation of the deaminated and N-acetylated analogs of benzidine, which have enhanced mutagenicity and lipophilicity, previously has not been attributed to the intestinal microbiota.

  8. Drug supersaturation in simulated and human intestinal fluids representing different nutritional states.

    Science.gov (United States)

    Bevernage, Jan; Brouwers, Joachim; Clarysse, Sarah; Vertzoni, Maria; Tack, Jan; Annaert, Pieter; Augustijns, Patrick

    2010-11-01

    It was the purpose of this study to explore supersaturation of poorly soluble drugs in human intestinal fluids (HIF), and to assess potential food effects on the creation and maintenance of supersaturation. Duodenal fluids were collected from healthy volunteers and pooled according to three nutritional states (fasted-, fed-, and fat-enriched fed state). Supersaturation was created at a fixed degree of supersaturation (DS=20) using the solvent-shift method. Fasted- and fed-state simulated intestinal fluids (FaSSIF and FeSSIF) were used as intestinal simulation media. Supersaturation in HIF showed to be stable up to a certain degree for different poorly soluble drugs. In HIF as well as in FaSSIF and FeSSIF, supersaturation appeared to be compound and medium specific. Supersaturation stability was found to be inversely proportional to the solubility in the corresponding media. Food intake affected itraconazole supersaturation positively. On the contrary, etravirine and loviride supersaturation decreased upon food intake. Supersaturation experiments in FaSSIF and FeSSIF showed similar results as in HIF for etravirine and loviride, whereas itraconazole supersaturation behaved differently in HIF versus simulation media. The present study illustrates, for the first time, that supersaturation can be created and maintained in HIF, even in the absence of excipients. © 2010 Wiley-Liss, Inc. and the American Pharmacists Association

  9. Infection with fully mature Corynosoma cf. validum causes ulcers in the human small intestine.

    Science.gov (United States)

    Takahashi, Keitaro; Ito, Takahiro; Sato, Tomonobu; Goto, Mitsuru; Kawamoto, Toru; Fujinaga, Akihiro; Yanagawa, Nobuyuki; Saito, Yoshinori; Nakao, Minoru; Hasegawa, Hideo; Fujiya, Mikihiro

    2016-06-01

    Corynosoma is a parasite that can normally be found in the intestinal tract of fish-eating mammals, particularly in seals and birds. The present case proposed that Corynosoma could attain full maturity in the human intestine. A 70-year-old female complained of abdominal pain. A computed tomography (CT) scan revealed a swelling of the intraperitoneal lymph nodes with no responsible lesion. Video capsule endoscopy and double-balloon endoscopy detected several ulcerations and one parasite in the ileum, which was tightly attached at the bottom of the ulcerations. The parasite was cylindrical and measured approximately 10 mm (long) x 3 mm (wide). Pathologically, the worm had a four-layered body wall and contained embryonated eggs. The sequences of the parasite-derived nuclear ribosomal DNA fragment and mitochondrial DNA fragment of cox1 were almost identical to those of Corynosoma validum. The patient's abdominal pain immediately improved after the administration of pyrantel pamoate (1,500 mg). Corynosoma was possibly the responsible disease in a patient who complained of abdominal pain and in whom no responsible lesion was detected by CT, gastroduodenoscopy or colonoscopy. Examinations of the small intestines should be aggressively performed in such cases.

  10. Bovine and soybean milk bioactive compounds: Effects on inflammatory response of human intestinal Caco-2 cells.

    Science.gov (United States)

    Calvello, Rosa; Aresta, Antonella; Trapani, Adriana; Zambonin, Carlo; Cianciulli, Antonia; Salvatore, Rosaria; Clodoveo, Maria Lisa; Corbo, Filomena; Franchini, Carlo; Panaro, Maria Antonietta

    2016-11-01

    In this study the effects of commercial bovine and soybean milks and their bioactive compounds, namely genistein, daidzein and equol, on the inflammatory responses induced by lipopolysaccharide (LPS) treatment of human intestinal Caco-2 cells were examined, in terms of nitric oxide (NO) release and inducible nitric oxide synthetase (iNOS) expression. Both milks and their bioactive compounds significantly inhibited, dose-dependently, the expression of iNOS mRNA and protein, resulting in a decreased NO production. The NF-κB activation in LPS-stimulated intestinal cells was also examined. In all cases we observed that cell pre-treatment before LPS activation inhibited the IkB phosphorylation. Accordingly, quantification of bioactive compounds by solid phase microextraction coupled with liquid chromatography has shown that they were absorbed, metabolized and released by Caco-2 cells in culture media. In conclusion, we demonstrated that milks and compounds tested are able to reduce LPS-induced inflammatory responses from intestinal cells, interfering with NF-kB dependent molecular mechanisms.

  11. Contribution of microbiota to the intestinal physicochemical barrier.

    Science.gov (United States)

    Malago, J J

    2015-01-01

    The large number of intestinal microorganisms, which exceeds the total number of human cells by ten folds, alludes to a significant contribution to human health. This is vivid in enteric and some systemic diseases emanating from disruption of the microbiota. As life style keeps shifting towards disruption of the microbiota in most societies worldwide, interest in the contribution of the microbiota to gut health has grown enormously. Many studies have been conducted to elucidate the exact contribution of the microbiota to human health. The knowledge gained from these studies indicates that the microbiota interacts with the intestinal milieu to maintain gut health. In this review, the crosstalk of microbiota with the intestinal physicochemical barrier pivotal to the gut innate immunity is highlighted. In particular, the review focuses on the role of the microbiota on competitive exclusion of pathogens, intestinal pH, epithelial mechanical barrier integrity, apical actin cytoskeleton, antimicrobial peptides, and the mucus layer. Understanding this microbe-host relationship will provide useful insight into overcoming some diseases related to the disruption of the host microbiota.

  12. Exogenous HIV-1 Nef upsets the IFN-γ-induced impairment of human intestinal epithelial integrity.

    Directory of Open Access Journals (Sweden)

    Maria Giovanna Quaranta

    Full Text Available BACKGROUND: The mucosal tissues play a central role in the transmission of HIV-1 infection as well as in the pathogenesis of AIDS. Despite several clinical studies reported intestinal dysfunction during HIV infection, the mechanisms underlying HIV-induced impairments of mucosal epithelial barrier are still unclear. It has been postulated that HIV-1 alters enterocytic function and HIV-1 proteins have been detected in several cell types of the intestinal mucosa. In the present study, we analyzed the effect of the accessory HIV-1 Nef protein on human epithelial cell line. METHODOLOGY/PRINCIPAL FINDINGS: We used unstimulated or IFN-γ-stimulated Caco-2 cells, as a model for homeostatic and inflamed gastrointestinal tracts, respectively. We investigated the effect of exogenous recombinant Nef on monolayer integrity analyzing its uptake, transepithelial electrical resistance, permeability to FITC-dextran and the expression of tight junction proteins. Moreover, we measured the induction of proinflammatory mediators. Exogenous Nef was taken up by Caco-2 cells, increased intestinal epithelial permeability and upset the IFN-γ-induced reduction of transepithelial resistance, interfering with tight junction protein expression. Moreover, Nef inhibited IFN-γ-induced apoptosis and up-regulated TNF-α, IL-6 and MIP-3α production by Caco-2 cells while down-regulated IL-10 production. The simultaneous exposure of Caco-2 cells to Nef and IFN-γ did not affect cytokine secretion respect to untreated cells. Finally, we found that Nef counteracted the IFN-γ induced arachidonic acid cascade. CONCLUSION/SIGNIFICANCE: Our findings suggest that exogenous Nef, perturbing the IFN-γ-induced impairment of intestinal epithelial cells, could prolong cell survival, thus allowing for accumulation of viral particles. Our results may improve the understanding of AIDS pathogenesis, supporting the discovery of new therapeutic interventions.

  13. Human in vivo regional intestinal permeability: importance for pharmaceutical drug development.

    Science.gov (United States)

    Lennernäs, Hans

    2014-01-01

    Both the development and regulation of pharmaceutical dosage forms have undergone significant improvements and development over the past 25 years, due primarily to the extensive application of the biopharmaceutical classification system (BCS). The Biopharmaceutics Drug Disposition Classification System, which was published in 2005, has also been a useful resource for predicting the influence of transporters in several pharmacokinetic processes. However, there remains a need for the pharmaceutical industry to develop reliable in vitro/in vivo correlations and in silico methods for predicting the rate and extent of complex gastrointestinal (GI) absorption, the bioavailability, and the plasma concentration-time curves for orally administered drug products. Accordingly, a more rational approach is required, one in which high quality in vitro or in silico characterizations of active pharmaceutical ingredients and formulations are integrated into physiologically based in silico biopharmaceutics models to capture the full complexity of GI drug absorption. The need for better understanding of the in vivo GI process has recently become evident after an unsuccessful attempt to predict the GI absorption of BCS class II and IV drugs. Reliable data on the in vivo permeability of the human intestine (Peff) from various intestinal regions is recognized as one of the key biopharmaceutical requirements when developing in silico GI biopharmaceutics models with improved predictive accuracy. The Peff values for human jejunum and ileum, based on historical open, single-pass, perfusion studies are presented in this review. The main objective of this review is to summarize and discuss the relevance and current status of these human in vivo regional intestinal permeability values.

  14. Metabolism of Kaempferia parviflora polymethoxyflavones by human intestinal bacterium Bautia sp. MRG-PMF1.

    Science.gov (United States)

    Kim, Mihyang; Kim, Nayoung; Han, Jaehong

    2014-12-24

    Poylmethoxyflavones (PMFs) are major bioactive flavonoids, which exhibit various biological activities, such as anticancer effects. The biotransformation of PMFs and characterization of a PMF-metabolizing human intestinal bacterium were studied herein for the first time. Hydrolysis of aryl methyl ether functional groups by human fecal samples was observed from the bioconversion of various PMFs. Activity-guided screening for PMF-metabolizing intestinal bacteria under anaerobic conditions resulted in the isolation of a strict anaerobic bacterium, which was identified as Blautia sp. MRG-PMF1. The isolated MRG-PMF1 was able to metabolize various PMFs to the corresponding demethylated flavones. The microbial conversion of bioactive 5,7-dimethoxyflavone (5,7-DMF) and 5,7,4'-trimethoxyflavone (5,7,4'-TMF) was studied in detail. 5,7-DMF and 5,7,4'-TMF were completely metabolized to 5,7-dihydroxyflavone (chrysin) and 5,7,4'-trihydroxyflavone (apigenin), respectively. From a kinetics study, the methoxy group on the flavone C-7 position was found to be preferentially hydrolyzed. 5-Methoxychrysin, the intermediate of 5,7-DMF metabolism by Blautia sp. MRG-PMF1, was isolated and characterized by nuclear magnetic resonance spectroscopy. Apigenin was produced from the sequential demethylation of 5,7,4'-TMF, via 5,4'-dimethoxy-7-hydroxyflavone and 7,4'-dihydroxy-5-methoxyflavone (thevetiaflavone). Not only demethylation activity but also deglycosylation activity was exhibited by Blautia sp. MRG-PMF1, and various flavonoids, including isoflavones, flavones, and flavanones, were found to be metabolized to the corresponding aglycones. The unprecedented PMF demethylation activity of Blautia sp. MRG-PMF1 will expand our understanding of flavonoid metabolism in the human intestine and lead to novel bioactive compounds.

  15. Conjunctival mucus ferning in hypovitaminosis A

    Directory of Open Access Journals (Sweden)

    Edward D

    1988-01-01

    Full Text Available The ocular ferning test was used to qualitatively assess mucus function in early stages of xerophthalmia. The results indicate that inspite of histological evidence of loss of goblet cells in the early stages, mucous function and production is sufficient to produce ferning. It is suggested that such derangements in mucous ferning may occur in more advanced stages of xerophthalmia.

  16. RGD-Dependent Epithelial Cell-Matrix Interactions in the Human Intestinal Crypt

    Directory of Open Access Journals (Sweden)

    Yannick D. Benoit

    2012-01-01

    Full Text Available Interactions between the extracellular matrix (ECM and integrin receptors trigger structural and functional bonds between the cell microenvironment and the cytoskeleton. Such connections are essential for adhesion structure integrity and are key players in regulating transduction of specific intracellular signals, which in turn regulate the organization of the cell microenvironment and, consequently, cell function. The RGD peptide-dependent integrins represent a key subgroup of ECM receptors involved in the maintenance of epithelial homeostasis. Here we review recent findings on RGD-dependent ECM-integrin interactions and their roles in human intestinal epithelial crypt cells.

  17. Characterization of macrophage-like cells in the external layers of human small and large intestine

    DEFF Research Database (Denmark)

    Mikkelsen, H B; Rumessen, J J

    1992-01-01

    -DR-positive (expressing the MHC class-II antigen), in contrast to macrophage-like cells in the subserosa and submucosa. Macrophage-like cells in the external muscle layer were mostly acid phosphatase-negative, and at the electron-microscopic level they were found to have features of macrophages: primary lysosomes, coated...... vesicles and pits. However, very few secondary lysosomes were present. Birbeck granules were not observed. It is concluded that in the external muscle layer of human small and large intestine numerous macrophages of a special type are present. It is discussed whether this cell type plays a role...

  18. Butyrate stimulates IL-32α expression in human intestinal epithelial cell lines

    Institute of Scientific and Technical Information of China (English)

    Ayako; Kobori; Shigeki; Bamba; Hirotsugu; Imaeda; Hiromitsu; Ban; Tomoyuki; Tsujikawa; Yasuharu; Saito; Yoshihide; Fujiyama; Akira; Andoh

    2010-01-01

    AIM: To investigate the effects of butyrate on interleukin (IL)-32α expression in epithelial cell lines. METHODS: The human intestinal epithelial cell lines HT-29, SW480, and T84 were used. Intracellular IL- 32α was determined by Western blotting analyses. IL- 32α mRNA expression was analyzed by real-time poly-merase chain reaction. RESULTS: Acetate and propionate had no effects on IL-32α mRNA expression. Butyrate significantly enhanced IL-32α expression in all cell lines. Butyrate also up-regulated IL-1β-i...

  19. Transepithelial transport of ambroxol hydrochloride across human intestinal Caco-2 cell monolayers.

    Science.gov (United States)

    Stetinová, Vera; Smetanová, Libuse; Kholová, Dagmar; Svoboda, Zbynek; Kvetina, Jaroslav

    2009-09-01

    This study aimed i) to characterize the transepithelial transport of the mucolytic agent ambroxol hydrochloride across the intestinal barrier, ii) to classify the ambroxol according to Biopharmaceutics Classification System (BCS) and iii) to predict ambroxol absorption in humans. Transport of ambroxol (100, 300 and 1000 micromol/l) was studied in a human colon carcinoma cell line Caco-2 in apical to basolateral and basolateral to apical direction, under iso-pH 7.4 and pH-gradient (6 vs. 7.4) conditions. The relative contribution of the paracellular route was estimated using Ca2+-free transport medium. Ambroxol samples from receiver compartments were analysed by HPLC with UV detection (242 nm). Results showed that ambroxol transport is linear with time, pH-dependent and direction-independent, displays non-saturable (first-order) kinetics. Thus, the transport seems to be transcellular mediated by passive diffusion. Estimated high solubility and high permeability (P(app) = 45 x 10(-6) cm/s) of ambroxol rank it among well absorbed compounds and class I of BCS. It can be expected that the oral dose fraction of ambroxol absorbed in human intestine is high.

  20. Combined Effects of Lipophilic Phycotoxins (Okadaic Acid, Azapsiracid-1 and Yessotoxin on Human Intestinal Cells Models

    Directory of Open Access Journals (Sweden)

    Pierre-Jean Ferron

    2016-02-01

    Full Text Available Phycotoxins are monitored in seafood because they can cause food poisonings in humans. Phycotoxins do not only occur singly but also as mixtures in shellfish. The aim of this study was to evaluate the in vitro toxic interactions of binary combinations of three lipophilic phycotoxins commonly found in Europe (okadaic acid (OA, yessotoxin (YTX and azaspiracid-1 (AZA-1 using the neutral red uptake assay on two human intestinal cell models, Caco-2 and the human intestinal epithelial crypt-like cells (HIEC. Based on the cytotoxicity of individual toxins, we studied the interactions between toxins in binary mixtures using the combination index-isobologram equation, a method widely used in pharmacology to study drug interactions. This method quantitatively classifies interactions between toxins in mixtures as synergistic, additive or antagonistic. AZA-1/OA, and YTX/OA mixtures showed increasing antagonism with increasing toxin concentrations. In contrast, the AZA-1/YTX mixture showed increasing synergism with increasing concentrations, especially for mixtures with high YTX concentrations. These results highlight the hazard potency of AZA-1/YTX mixtures with regard to seafood intoxication.

  1. Transesterification of a series of 12 parabens by liver and small-intestinal microsomes of rats and humans.

    Science.gov (United States)

    Fujino, Chieri; Watanabe, Yoko; Uramaru, Naoto; Kitamura, Shigeyuki

    2014-02-01

    Hydrolytic transformation of parabens (4-hydroxybenzoic acid esters; used as antibacterial agents) to 4-hydroxybenzoic acid and alcohols by tissue microsomes is well-known both in vitro and in vivo. Here, we investigated transesterification reactions of parabens catalyzed by rat and human microsomes, using a series of 12 parabens with C1-C12 alcohol side chains. Transesterification of parabens by rat liver and small-intestinal microsomes occurred in the presence of alcohols in the microsomal incubation mixture. Among the 12 parabens, propylparaben was most effectively transesterified by rat liver microsomes with methanol or ethanol, followed by butylparaben. Relatively low activity was observed with longer-side-chain parabens. In contrast, small-intestinal microsomes exhibited higher activity towards moderately long side-chain parabens, and showed the highest activity toward octylparaben. When parabens were incubated with liver or small-intestinal microsomes in the presence of C1-C12 alcohols, ethanol and decanol were most effectively transferred to parabens by rat liver microsomes and small-intestinal microsomes, respectively. Human liver and small-intestinal microsomes also exhibited significant transesterification activities with different substrate specificities, like rat microsomes. Carboxylesterase isoforms, CES1b and CES1c, and CES2, exhibited significant transesterification activity toward parabens, and showed similar substrate specificity to human liver and small-intestinal microsomes, respectively. Copyright © 2013 Elsevier Ltd. All rights reserved.

  2. Initiation of an inflammatory response in resident intestinal lamina propria cells -use of a human organ culture model.

    Directory of Open Access Journals (Sweden)

    Jutta Schröder-Braunstein

    Full Text Available Resident human lamina propria immune cells serve as powerful effectors in host defense. Molecular events associated with the initiation of an intestinal inflammatory response in these cells are largely unknown. Here, we aimed to characterize phenotypic and functional changes induced in these cells at the onset of intestinal inflammation using a human intestinal organ culture model. In this model, healthy human colonic mucosa was depleted of epithelial cells by EDTA treatment. Following loss of the epithelial layer, expression of the inflammatory mediators IL1B, IL6, IL8, IL23A, TNFA, CXCL2, and the surface receptors CD14, TLR2, CD86, CD54 was rapidly induced in resident lamina propria cells in situ as determined by qRT-PCR and immunohistology. Gene microarray analysis of lamina propria cells obtained by laser-capture microdissection provided an overview of global changes in gene expression occurring during the initiation of an intestinal inflammatory response in these cells. Bioinformatic analysis gave insight into signalling pathways mediating this inflammatory response. Furthermore, comparison with published microarray datasets of inflamed mucosa in vivo (ulcerative colitis revealed a significant overlap of differentially regulated genes underlining the in vivo relevance of the organ culture model. Furthermore, genes never been previously associated with intestinal inflammation were identified using this model. The organ culture model characterized may be useful to study molecular mechanisms underlying the initiation of an intestinal inflammatory response in normal mucosa as well as potential alterations of this response in inflammatory bowel disease.

  3. Intestinal parasite co-infection among pulmonary tuberculosis cases without human immunodeficiency virus infection in a rural county in China.

    Science.gov (United States)

    Li, Xin-Xu; Chen, Jia-Xu; Wang, Li-Xia; Tian, Li-Guang; Zhang, Yu-Ping; Dong, Shuang-Pin; Hu, Xue-Guang; Liu, Jian; Wang, Feng-Feng; Wang, Yue; Yin, Xiao-Mei; He, Li-Jun; Yan, Qiu-Ye; Zhang, Hong-Wei; Xu, Bian-Li; Zhou, Xiao-Nong

    2014-01-01

    Epidemiologic studies of co-infection with tuberculosis (TB) and intestinal parasites in humans have not been extensively investigated in China. A cross-section study was conducted in a rural county of Henan Province, China. Pulmonary TB (PTB) case-patients receiving treatment for infection with Mycobacterium tuberculosis and healthy controls matched for geographic area, age, and sex were surveyed by using questionnaires. Fecal and blood specimens were collected for detection of intestinal parasites, routine blood examination, and infection with human immunodeficiency virus. The chi-square test was used for univariate analysis and multivariate logistic regression models were used to adjust for potential confounding factors. A total of 369 persons with PTB and 366 healthy controls were included; all participants were negative for human immunodeficiency virus. The overall prevalence of intestinal parasites in persons with PTB was 14.9%, including intestinal protozoa (7.9%) and helminthes (7.6%). The infection spectrum of intestinal parasites was Entamoeba spp. (1.4%), Blastocystis hominis (6.2%), Trichomonas hominis (0.3%), Clonorchis sinensis (0.3%), Ascaris lumbricoides (0.5%), Trichuris trichiura (2.2%), and hookworm (4.6%). The prevalence of intestinal parasites showed no significant difference between persons with PTB and healthy controls after adjusting for potential confounding factors. There was no factor that affected infection rates for intestinal parasites between the two groups. Infection with intestinal parasites of persons with PTB was associated with female sex (adjusted odds ratio [AOR] = 2.05, 95% confidence interval [CI] = 1.01-4.17), body mass index ≤ 19 (AOR = 3.02, 95% CI = 1.47-6.20), and anemia (AOR = 2.43, 95% CI = 1.17-5.03). Infection of healthy controls was only associated with an annual labor time in farmlands > 2 months (AOR = 4.50, 95% CI = 2.03-10.00). In addition, there was no significant trend between rates of infection with

  4. Mouse and human intestinal immunity: same ballpark, different players; different rules, same score.

    Science.gov (United States)

    Gibbons, D L; Spencer, J

    2011-03-01

    The study of animal immune physiology and animal models of human disease have accelerated many aspects of translational research by allowing direct, definitive investigations. In particular, the use of mice has allowed genetic manipulation, adoptive transfer, immunization, and focused cell and tissue sampling, which would obviously be unthinkable for studies in humans. However, the disease relevance of some animal models may be uncertain and difficulties in interpretation may occur as a consequence of immunological differences between the two species. In this review, we will consider general differences in the structure and development of human and mouse mucosal lymphoid microenvironments and then discuss species differences in mucosal B- and T-cell biology that relate to the current concepts of intestinal immune function.

  5. Loss of sigma factor RpoN increases intestinal colonization of Vibrio parahaemolyticus in an adult mouse model.

    Science.gov (United States)

    Whitaker, W Brian; Richards, Gary P; Boyd, E Fidelma

    2014-02-01

    Vibrio parahaemolyticus is the leading cause of bacterial seafood-borne gastroenteritis worldwide, yet little is known about how this pathogen colonizes the human intestine. The alternative sigma factor RpoN/sigma-54 is a global regulator that controls flagellar synthesis, as well as a wide range of nonflagellar genes. We constructed an in-frame deletion mutation in rpoN (VP2670) in V. parahaemolyticus RIMD2210633, a clinical serogroup O3:K6 isolate, and examined the effects in vivo using a streptomycin-treated mouse model of colonization. We confirmed that deletion of rpoN rendered V. parahaemolyticus nonmotile, and it caused reduced biofilm formation and an apparent defect in glutamine synthetase production. In in vivo competition assays between the rpoN mutant and a wild-type RIMD2210633 strain marked with the β-galactosidase gene lacZ (WBWlacZ), the mutant colonized significantly more proficiently. Intestinal persistence competition assays also demonstrated that the rpoN mutant had enhanced fitness and outcompeted WBWlacZ. Mutants defective in the polar flagellum biosynthesis FliAP sigma factor also outcompeted WBWlacZ but not to the same level as the rpoN mutant, which suggested that lack of motility is not the sole cause of the fitness effect. In an in vitro growth competition assay in mouse intestinal mucus, the rpoN mutant also outcompeted the wild type and exhibited faster doubling times when grown in mucus and on individual components of mucus. Genes in the pathways for the catabolism of mucus sugars also had significantly higher expression levels in a ΔrpoN mutant than in the wild type. These data suggest that in V. parahaemolyticus, RpoN plays an important role in carbon utilization regulation, which may significantly affect host colonization.

  6. Cathelicidin stimulates colonic mucus synthesis by up-regulating MUC1 and MUC2 expression through a mitogen-activated protein kinase pathway

    Institute of Scientific and Technical Information of China (English)

    CHO Chi-hin

    2008-01-01

    Objective Mucus forms the physical barrier along the gastrointestinal (GI) tract. It plays an important role to prevent mucosal damage and inflammation. Our previous finding showed that antibacterial peptide 'cathelicidin' increased mucus thickness and prevented inflammation in the colon. In the current study, we examined the protective mechanisms by which the peptide increased mucus synthesis in vitro. Methods Human colonic cell line (HT-29) was used to assess the stimulatory action of cathelicidin on mucus synthesis which was measured by the D-[6-3H] glucosamine incorporation assay. Results Human cathelicidin (LL-37) dose-dependently (10-40 μg·mL-1) and significantly stimulated mucus synthesis. Real-time PCR data showed that addition of LL-37 induced more than 50 % increase in MUC1 and MUC2 mRNA levels. Treatment with MUC1 and MUC2 siRNAs normalized the stimulatory action of LL-37 on mucus synthesis. LL-37 also activated the phosphorylation of mitogen-activated protein (MAP) kinase in the cells. A specific inhibitor of the MAP kinase pathway, U0126, completely blocked the increase of MUC1 and MUC2 expression as well as mucus synthesis by LL-37. Conclusions Taken together LL-37 stimulates mucus synthesis through the activation of MUC1 and MUC2 expression and the MAP kinase pathway in human colonic cells.

  7. Resveratrol inhibits mucus overproduction and MUC5AC expression in a murine model of asthma.

    Science.gov (United States)

    Ni, Zhen-Hua; Tang, Ji-Hong; Chen, Guo; Lai, Yi-Min; Chen, Qing-Ge; Li, Zao; Yang, Wei; Luo, Xu-Min; Wang, Xiong-Biao

    2016-01-01

    Previous in vitro studies have demonstrated that resveratrol is able to significantly inhibit the upregulation of mucin 5AC (MUC5AC), a major component of mucus; thus indicating that resveratrol may have potential in regulating mucus overproduction. However, there have been few studies regarding the resveratrol‑mediated prevention of MUC5AC overproduction in vivo, and the mechanisms by which resveratrol regulates MUC5AC expression have yet to be elucidated. In the present study, an ovalbumin (OVA)‑challenged murine model of asthma was used to assess the effects of resveratrol treatment on mucus production in vivo. The results demonstrated that resveratrol significantly inhibited OVA‑induced airway inflammation and mucus production. In addition, the mRNA and protein expression levels of MUC5AC were increased in the OVA‑challenged mice, whereas treatment with resveratrol significantly inhibited this effect. The expression levels of murine calcium‑activated chloride channel (mCLCA)3, an important key mediator of MUC5AC production, were also reduced following resveratrol treatment. Furthermore, in vitro studies demonstrated that resveratrol significantly inhibited human (h)CLCA1 and MUC5AC expression in a dose‑dependent manner. These results indicated that resveratrol was effective in preventing mucus overproduction and MUC5AC expression in vivo, and its underlying mechanism may be associated with regulation of the mCLCA3/hCLCA1 signaling pathway.

  8. Consumption of milk from transgenic goats expressing human lysozyme in the mammary gland results in the modulation of intestinal microflora.

    Science.gov (United States)

    Maga, Elizabeth A; Walker, Richard L; Anderson, Gary B; Murray, James D

    2006-08-01

    Lysozyme is a key antimicrobial component of human milk that has several health-promoting functions including the development of a healthy intestinal tract. However, levels of lysozyme in the milk of dairy animals are negligible. We have generated transgenic dairy goats that express human lysozyme (HLZ) in their milk in an attempt to deliver the benefits of human milk in a continual fashion. To test the feasibility of this transgenic approach to achieve a biological impact at the level of the intestine, feeding trials were conducted in two animal models. Pasteurized milk from HLZ transgenic animals was fed to both kid goats (ruminant model) and young pigs (human model), and the numbers of total coliforms and Escherichia coli present in the small intestine were determined. Data from this proof-of-principle study demonstrate that milk from transgenic animals was capable of modulating the bacterial population of the gut in both animal models. Pigs that consumed pasteurized milk from HLZ transgenic goats had fewer numbers of coliforms and E. coli in their intestine than did those receiving milk from non-transgenic control animals. The opposite effect was seen in goats. Milk from these transgenic animals not only represent one of the first transgenic food products with the potential of benefiting human health, but are also a unique model to study the development and role of intestinal microflora on health, well-being and resistance to disease.

  9. High taxonomic level fingerprint of the human intestinal microbiota by ligase detection reaction--universal array approach.

    Science.gov (United States)

    Candela, Marco; Consolandi, Clarissa; Severgnini, Marco; Biagi, Elena; Castiglioni, Bianca; Vitali, Beatrice; De Bellis, Gianluca; Brigidi, Patrizia

    2010-04-19

    Affecting the core functional microbiome, peculiar high level taxonomic unbalances of the human intestinal microbiota have been recently associated with specific diseases, such as obesity, inflammatory bowel diseases, and intestinal inflammation. In order to specifically monitor microbiota unbalances that impact human physiology, here we develop and validate an original DNA-microarray (HTF-Microbi.Array) for the high taxonomic level fingerprint of the human intestinal microbiota. Based on the Ligase Detection Reaction-Universal Array (LDR-UA) approach, the HTF-Microbi.Array enables specific detection and approximate relative quantification of 16S rRNAs from 30 phylogenetically related groups of the human intestinal microbiota. The HTF-Microbi.Array was used in a pilot study of the faecal microbiota of eight young adults. Cluster analysis revealed the good reproducibility of the high level taxonomic microbiota fingerprint obtained for each of the subject. The HTF-Microbi.Array is a fast and sensitive tool for the high taxonomic level fingerprint of the human intestinal microbiota in terms of presence/absence of the principal groups. Moreover, analysis of the relative fluorescence intensity for each probe pair of our LDR-UA platform can provide estimation of the relative abundance of the microbial target groups within each samples. Focusing the phylogenetic resolution at division, order and cluster levels, the HTF-Microbi.Array is blind with respect to the inter-individual variability at the species level.

  10. Genomic characterization of non-mucus-adherent derivatives of Lactobacillus rhamnosus GG reveals genes affecting pilus biogenesis.

    Science.gov (United States)

    Rasinkangas, Pia; Reunanen, Justus; Douillard, François P; Ritari, Jarmo; Uotinen, Virva; Palva, Airi; de Vos, Willem M

    2014-11-01

    Lactobacillus rhamnosus GG is one of the best-characterized lactic acid bacteria and can be considered a probiotic paradigm. Comparative and functional genome analysis showed that L. rhamnosus GG harbors a genomic island including the spaCBA-srtC1 gene cluster, encoding the cell surface-decorating host-interacting pili. Here, induced mutagenesis was used to study pilus biogenesis in L. rhamnosus GG. A combination of two powerful approaches, mutation selection and next-generation sequencing, was applied to L. rhamnosus GG for the selection of pilus-deficient mutants from an enriched population. The isolated mutants were first screened by immuno-dot blot analysis using antiserum against pilin proteins. Relevant mutants were selected, and the lack of pili was confirmed by immunoelectron microscopy. The pilosotype of 10 mutant strains was further characterized by analyzing pilin expression using Western blot, dot blot, and immunofluorescence methods. A mucus binding assay showed that the mutants did not adhere to porcine intestinal mucus. Comparative genome sequence analysis using the Illumina MiSeq platform allowed us to determine the nature of the mutations in the obtained pilus-deficient derivatives. Three major classes of mutants with unique genotypes were observed: class I, with mutations in the srtC1 gene; class II, with a deletion containing the spaCBA-srtC1 gene cluster; and class III, with mutations in the spaA gene. Only a limited number of collateral mutations were observed, and one of the pilus-deficient derivatives with a deficient srtC1 gene contained 24 other mutations. This strain, PB12, can be considered a candidate for human trials addressing the impact of the absence of pili.

  11. Description of urolithin production capacity from ellagic acid of two human intestinal Gordonibacter species.

    Science.gov (United States)

    Selma, María V; Beltrán, David; García-Villalba, Rocío; Espín, Juan C; Tomás-Barberán, Francisco A

    2014-08-01

    Ellagitannin and ellagic acid metabolism to urolithins in the gut shows a large human interindividual variability and this has been associated with differences in the colon microbiota. In the present study we describe the isolation of one urolithin-producing strain from the human faeces of a healthy volunteer and the ellagic acid transformation to different urolithin metabolites by two species of intestinal bacteria. The isolate belongs to a new species described as Gordonibacter urolithinfaciens, sp. nov. The type strain of the Gordonibacter genus, Gordonibacter pamelaeae DSM 19378(T), was also demonstrated to produce urolithins. Both human intestinal bacteria grew similarly in the presence and absence of ellagic acid at 30 μM concentration. Ellagic acid catabolism and urolithin formation occurred during the stationary phase of the growth of the bacteria under anaerobic conditions. The HPLC-MS analyses showed the sequential production of pentahydroxy-urolithin (urolithin M-5), tetrahydroxy-urolithin (urolithin M-6) and trihydroxy-urolithin (urolithin C), while dihydroxy-urolithins (urolithin A and isourolithin A), and monohydroxy-urolithin (urolithin B) were not produced in pure cultures. Consequently, either other bacteria from the gut or the physiological conditions found in vivo are necessary for completing metabolism until the final urolithins (dihydroxy and monohydroxy urolithins) are produced. This is the first time that the urolithin production capacity of pure strains has been demonstrated. The identification of the urolithin-producing bacteria is a relevant outcome as urolithin implication in health (cardiovascular protection, anti-inflammatory and anticarcinogenic properties) has been supported by different bioassays and urolithins can be used in the development of functional foods and nutraceuticals. This study represents an initial work that opens interesting possibilities of describing enzymatic activities involved in urolithin production that can

  12. Decreased colonic mucus in rats with loperamide-induced constipation.

    Science.gov (United States)

    Shimotoyodome, A; Meguro, S; Hase, T; Tokimitsu, I; Sakata, T

    2000-06-01

    Constipation is a risk factor of colorectal cancer. Mucin is a major component of lumenal mucus, which protects the colorectal mucosa against mechanical and chemical damage. The aim of this study was to evaluate mucus production and to quantitate lumen mucus in a rat model of spastic constipation. We induced constipation with loperamide (1.5 mg/kg), and histochemically evaluated mucus production and the thickness of the mucus layer at the fecal surface. We quantitated the mucus attached to the mucosal surface using colonic perfusion with N-acetylcysteine. While more feces remained in the colon, there was less fecal excretion and lower fecal water content in loperamide-administered rats than in control rats. Crypt epithelial cells contained less mucus in constipated rats than in control rats. The mucus layer at the fecal surface was thinner and less mucus was recovered from the mucosal surface in constipated rats than in control rats. Mucus production of crypt epithelial cells and mucus at the fecal and mucosal surface were reduced by loperamide-induced constipation.

  13. Intestinal microbiota and human diseases%肠道微生物与人类疾病

    Institute of Scientific and Technical Information of China (English)

    王子恺; 杨云生

    2012-01-01

    肠道内数以亿计的微生物及其代谢产物在人体能量代谢、营养物质吸收、先天和获得性免疫、胃肠道功能等方面发挥着重要作用,一旦宿主与肠道微生物之间共栖共生的稳态被打破,就会诱发多种人类疾病.目前已经认识到肠道微生物与人类健康和疾病的密切关系,仅仅从人类自身角度出发来研究人类疾病远远不够,必须考虑到与人类共栖共生的肠道微生物的作用.本文就近年来有关肠道微生物与人类疾病关系研究的进展进行综述.%The majority of human intestinal microbiota are harmless or even beneficial by performing functions essential for our survival. Changes in the microbial species that reside in our intestines have been associated with a long list of illness. The review provided an overview of the association between the microbiota and the occurrence of human diseases, and to stimulate future researches regarding infectious diseases and their consequences.

  14. Sugars increase non-heme iron bioavailability in human epithelial intestinal and liver cells.

    Directory of Open Access Journals (Sweden)

    Tatiana Christides

    Full Text Available Previous studies have suggested that sugars enhance iron bioavailability, possibly through either chelation or altering the oxidation state of the metal, however, results have been inconclusive. Sugar intake in the last 20 years has increased dramatically, and iron status disorders are significant public health problems worldwide; therefore understanding the nutritional implications of iron-sugar interactions is particularly relevant. In this study we measured the effects of sugars on non-heme iron bioavailability in human intestinal Caco-2 cells and HepG2 hepatoma cells using ferritin formation as a surrogate marker for iron uptake. The effect of sugars on iron oxidation state was examined by measuring ferrous iron formation in different sugar-iron solutions with a ferrozine-based assay. Fructose significantly increased iron-induced ferritin formation in both Caco-2 and HepG2 cells. In addition, high-fructose corn syrup (HFCS-55 increased Caco-2 cell iron-induced ferritin; these effects were negated by the addition of either tannic acid or phytic acid. Fructose combined with FeCl3 increased ferrozine-chelatable ferrous iron levels by approximately 300%. In conclusion, fructose increases iron bioavailability in human intestinal Caco-2 and HepG2 cells. Given the large amount of simple and rapidly digestible sugars in the modern diet their effects on iron bioavailability may have important patho-physiological consequences. Further studies are warranted to characterize these interactions.

  15. Cockroaches as carriers of human intestinal parasites in two localities in Ethiopia.

    Science.gov (United States)

    Kinfu, Addisu; Erko, Berhanu

    2008-11-01

    A study was undertaken to assess the role of cockroaches as potential carriers of human intestinal parasites in Addis Ababa and Ziway, Ethiopia. A total of 6480 cockroaches were trapped from the two localities from October 2006 to March 2007. All the cockroaches trapped in Addis Ababa (n=2240) and almost 50% (2100/4240) of those trapped in Ziway were identified as Blattella germanica. The rest of the cockroaches trapped in Ziway were identified as Periplaneta brunnea (24.52%), Pycnoscelus surinamensis (16.03%) and Supella longipalpa (9.90%). Microscopic examination of the external body washes of pooled cockroaches and individual gut contents revealed that cockroaches are carriers of Entamoeba coli and Entamoeba histolytica/dispar cysts as well as Enterobius vermicularis, Trichuris trichiura, Taenia spp. and Ascaris lumbricoides ova. Besides their role as a nuisance, the present study further confirms that cockroaches serve as carriers of human intestinal parasites. The possible association of cockroaches with allergic conditions such as asthma is also discussed. Hence, appropriate control measures should be taken particularly to make hotels and residential areas free of cockroaches as they represent a health risk.

  16. The Modulatory Effect of Anthocyanins from Purple Sweet Potato on Human Intestinal Microbiota in Vitro.

    Science.gov (United States)

    Zhang, Xin; Yang, Yang; Wu, Zufang; Weng, Peifang

    2016-03-30

    In order to investigate the modulatory effect of purple sweet potato anthocyanins (PSPAs) on human intestinal microbiota, PSPAs were prepared by column chromatography and their influence on intestinal microbiota was analyzed by monitoring the bacterial populations and analyzing short-chain fatty acid (SCFA) concentrations at different time points. The numbers (log10 cell/mL) of Bifidobacterium and Lactobacillus/Enterococcus spp., Bacteroides-Prevotella, Clostridium histolyticum, and total bacteria after 24 h of culture in anaerobic fermentation broth containing PSPAs were 8.44 ± 0.02, 8.30 ± 0.01, 7.80 ± 0.03, 7.60 ± 0.03, and 9.00 ± 0.02, respectively, compared with 8.21 ± 0.03, 8.12 ± 0.02, 7.95 ± 0.02, 7.77 ± 0.02, and 9.01 ± 0.03, respectively, in the controls. The results showed that PSPAs induced the proliferation of Bifidobacterium and Lactobacillus/Enterococcus spp., inhibited the growth of Bacteroides-Prevotella and Clostridium histolyticum, and did not affect the total bacteria number. Total SCFA concentrations in the cultures with PSPAs were significantly higher than in the controls (P microbiota, contributing to improvements in human health.

  17. The Intestinal Transport of Bovine Milk Exosomes Is Mediated by Endocytosis in Human Colon Carcinoma Caco-2 Cells and Rat Small Intestinal IEC-6 Cells.

    Science.gov (United States)

    Wolf, Tovah; Baier, Scott R; Zempleni, Janos

    2015-10-01

    MicroRNAs play essential roles in gene regulation. A substantial fraction of microRNAs in tissues and body fluids is encapsulated in exosomes, thereby conferring protection against degradation and a pathway for intestinal transport. MicroRNAs in cow milk are bioavailable in humans. This research assessed the transport mechanism of bovine milk exosomes, and therefore microRNAs, in human and rodent intestinal cells. The intestinal transport of bovine milk exosomes and microRNAs was assessed using fluorophore-labeled bovine milk exosomes in human colon carcinoma Caco-2 cells and rat small intestinal IEC-6 cells. Transport kinetics and mechanisms were characterized using dose-response studies, inhibitors of vesicle transport, carbohydrate competitors, proteolysis of surface proteins on cells and exosomes, and transepithelial transport in transwell plates. Exosome transport exhibited saturation kinetics at 37°C [Michaelis constant (Km) = 55.5 ± 48.6 μg exosomal protein/200 μL of media; maximal transport rate = 0.083 ± 0.057 ng of exosomal protein · 81,750 cells(-1) · h(-1)] and decreased by 64% when transport was measured at 4°C, consistent with carrier-mediated transport in Caco-2 cells. Exosome uptake decreased by 61-85% under the following conditions compared with controls in Caco-2 cells: removal of exosome and cell surface proteins by proteinase K, inhibition of endocytosis and vesicle trafficking by synthetic inhibitors, and inhibition of glycoprotein binding by carbohydrate competitors. When milk exosomes, at a concentration of 5 times the Km, were added to the upper chamber in transwell plates, Caco-2 cells accumulated miR-29b and miR-200c in the lower chamber, and reverse transport was minor. Transport characteristics were similar in IEC-6 cells and Caco-2 cells, except that substrate affinity and transporter capacity were lower and higher, respectively. The uptake of bovine milk exosomes is mediated by endocytosis and depends on cell and exosome

  18. Contributions of microbiome and mechanical deformation to intestinal bacterial overgrowth and inflammation in a human gut-on-a-chip.

    Science.gov (United States)

    Kim, Hyun Jung; Li, Hu; Collins, James J; Ingber, Donald E

    2016-01-05

    A human gut-on-a-chip microdevice was used to coculture multiple commensal microbes in contact with living human intestinal epithelial cells for more than a week in vitro and to analyze how gut microbiome, inflammatory cells, and peristalsis-associated mechanical deformations independently contribute to intestinal bacterial overgrowth and inflammation. This in vitro model replicated results from past animal and human studies, including demonstration that probiotic and antibiotic therapies can suppress villus injury induced by pathogenic bacteria. By ceasing peristalsis-like motions while maintaining luminal flow, lack of epithelial deformation was shown to trigger bacterial overgrowth similar to that observed in patients with ileus and inflammatory bowel disease. Analysis of intestinal inflammation on-chip revealed that immune cells and lipopolysaccharide endotoxin together stimulate epithelial cells to produce four proinflammatory cytokines (IL-8, IL-6, IL-1β, and TNF-α) that are necessary and sufficient to induce villus injury and compromise intestinal barrier function. Thus, this human gut-on-a-chip can be used to analyze contributions of microbiome to intestinal pathophysiology and dissect disease mechanisms in a controlled manner that is not possible using existing in vitro systems or animal models.

  19. Modified-chitosan/siRNA nanoparticles downregulate cellular CDX2 expression and cross the gastric mucus barrier.

    Directory of Open Access Journals (Sweden)

    Ana Sadio

    Full Text Available Development of effective non-viral vectors is of crucial importance in the implementation of RNA interference in clinical routine. The localized delivery of siRNAs to the gastrointestinal mucosa is highly desired but faces specific problems such as the stability in gastric acidity conditions and the presence of the mucus barrier. CDX2 is a transcription factor critical for intestinal differentiation being involved in the initiation and maintenance of gastrointestinal diseases. Specifically, it is the trigger of gastric intestinal metaplasia which is a precursor lesion of gastric cancer. Its expression is also altered in colorectal cancer, where it may constitute a lineage-survival oncogene. Our main objective was to develop a nanoparticle-delivery system of siRNA targeting CDX2 using modified chitosan as a vector. CDX2 expression was assessed in gastric carcinoma cell lines and nanoparticles behaviour in gastrointestinal mucus was tested in mouse explants. We show that imidazole-modified chitosan and trimethylchitosan/siRNA nanoparticles are able to downregulate CDX2 expression and overpass the gastric mucus layer but not colonic mucus. This system might constitute a potential therapeutic approach to treat CDX2-dependent gastric lesions.

  20. Doxycycline protects human intestinal cells from hypoxia/reoxygenation injury: Implications from an in-vitro hypoxia model.

    Science.gov (United States)

    Hummitzsch, Lars; Zitta, Karina; Berndt, Rouven; Kott, Matthias; Schildhauer, Christin; Parczany, Kerstin; Steinfath, Markus; Albrecht, Martin

    2017-04-15

    Intestinal ischemia/reperfusion (I/R) injury is a grave clinical emergency and associated with high morbidity and mortality rates. Based on the complex underlying mechanisms, a multimodal pharmacological approach seems necessary to prevent intestinal I/R injury. The antibiotic drug doxycycline, which exhibits a wide range of pleiotropic therapeutic properties, might be a promising candidate for also reducing I/R injury in the intestine. To investigate possible protective effects of doxycycline on intestinal I/R injury, human intestinal CaCo-2 cells were exposed to doxycycline at clinically relevant concentrations. In order to mimic I/R injury, CaCo-2 were thereafter subjected to hypoxia/reoxygenation by using our recently described two-enzyme in-vitro hypoxia model. Investigations of cell morphology, cell damage, apoptosis and hydrogen peroxide formation were performed 24h after the hypoxic insult. Hypoxia/reoxygenation injury resulted in morphological signs of cell damage, elevated LDH concentrations in the respective culture media (P<0.001) and increased protein expression of proapoptotic caspase-3 (P<0.05) in the intestinal cultures. These events were associated with increased levels hydrogen peroxide (P<0.001). Preincubation of CaCo-2 cells with different concentrations of doxycycline (5µM, 10µM, 50µM) reduced the hypoxia induced signs of cell damage and LDH release (P<0.001 for all concentrations). The reduction of cellular damage was associated with a reduced expression of caspase-3 (5µM, P<0.01; 10µM, P<0.01; 50µM, P<0.05), while hydrogen peroxide levels remained unchanged. In summary, doxycycline protects human intestinal cells from hypoxia/reoxygenation injury in-vitro. Further animal and clinical studies are required to prove the protective potential of doxycycline on intestinal I/R injury under in-vivo conditions.

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

    Science.gov (United States)

    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.

  2. A poly(ethylene glycol)-based surfactant for formulation of drug-loaded mucus penetrating particles.

    Science.gov (United States)

    Mert, Olcay; Lai, Samuel K; Ensign, Laura; Yang, Ming; Wang, Ying-Ying; Wood, Joseph; Hanes, Justin

    2012-02-10

    Mucosal surfaces are protected by a highly viscoelastic and adhesive mucus layer that traps most foreign particles, including conventional drug and gene carriers. Trapped particles are eliminated on the order of seconds to hours by mucus clearance mechanisms, precluding sustained and targeted drug and nucleic acid delivery to mucosal tissues. We have previously shown that polymeric coatings that minimize adhesive interactions with mucus constituents lead to particles that rapidly penetrate human mucus secretions. Nevertheless, a particular challenge in formulating drug-loaded mucus penetrating particles (MPP) is that many commonly used surfactants are either mucoadhesive, or do not facilitate efficient drug encapsulation. We tested a novel surfactant molecule for particle formulation composed of Vitamin E conjugated to 5 kDa poly(ethylene glycol) (VP5k). We show that VP5k-coated poly(lactide-co-glycolide) (PLGA) nanoparticles rapidly penetrate human cervicovaginal mucus, whereas PLGA nanoparticles coated with polyvinyl alcohol or Vitamin E conjugated to 1 kDa PEG were trapped. Importantly, VP5k facilitated high loading of paclitaxel, a frontline chemo drug, into PLGA MPP, with controlled release for at least 4 days and negligible burst release. Our results offer a promising new method for engineering biodegradable, drug-loaded MPP for sustained and targeted delivery of therapeutics at mucosal surfaces.

  3. Free fucose is a danger signal to human intestinal epithelial cells.

    Science.gov (United States)

    Chow, Wai Ling; Lee, Yuan Kun

    2008-03-01

    Fucose is present in foods, and it is a major component of human mucin glycoproteins and glycolipids. l-Fucose can also be found at the terminal position of many cell-surface oligosaccharide ligands that mediate cell-recognition and adhesion-signalling pathways. Mucin fucose can be released through the hydrolytic activity of pathogens and indigenous bacteria, leading to the release of free fucose into the intestinal lumen. The immunomodulating effects of free fucose on intestinal epithelial cells (enterocyte-like Caco-2) were investigated. It was found that the presence of l-fucose up regulated genes and secretion of their encoded proteins that are involved in both the innate and adaptive immune responses, possibly via the toll-like receptor-2 signalling pathway. These include TNFSF5, TNFSF7, TNF-alpha, IL12, IL17 and IL18. Besides modulating immune reactions in differentiated Caco-2 cells, fucose induced a set of cytokine genes that are involved in the development and proliferation of immune cells. These include the bone morphogenetic proteins (BMP) BMP2, BMP4, IL5, thrombopoietin and erythropoietin. In addition, the up regulated gene expression of fibroblast growth factor-2 may help to promote epithelial cell restitution in conjunction with the enhanced expression of transforming growth factor-beta mRNA. Since the exogenous fucose was not metabolised by the differentiated Caco-2 cells as a carbon source, the reactions elicited were suggested to be a result of the direct interaction of fucose and differentiated Caco-2 cells. The presence of free fucose may signal the invasion of mucin-hydrolysing microbial cells and breakage of the mucosal barrier. The intestinal epithelial cells respond by up regulation and secretion of cytokines, pre-empting the actual invasion of pathogens.

  4. Skin mucus proteins of lumpsucker (Cyclopterus lumpus

    Directory of Open Access Journals (Sweden)

    Deepti Manjari Patel

    2017-03-01

    Full Text Available Fish skin mucus serves as a first line of defense against pathogens and external stressors. In this study the proteomic profile of lumpsucker skin mucus was characterized using 2D gels coupled with tandem mass spectrometry. Mucosal proteins were identified by homology searches across the databases SwissProt, NCBInr and vertebrate EST. The identified proteins were clustered into ten groups based on their gene ontology biological process in PANTHER (www.patherdb.org. Calmodulin, cystatin-B, histone H2B, peroxiredoxin1, apolipoprotein A1, natterin-2, 14-3-3 protein, alfa enolase, pentraxin, warm temperature acclimation 65 kDa (WAP65kDa and heat shock proteins were identified. Several of the proteins are known to be involved in immune and/or stress responses. Proteomic profile established in this study could be a benchmark for differential proteomics studies.

  5. Human intestinal parasites in the past: new findings and a review

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    Marcelo Luiz Carvalho Gonçalves

    2003-01-01

    Full Text Available Almost all known human specific parasites have been found in ancient feces. A review of the paleoparasitological helminth and intestinal protozoa findings available in the literature is presented. We also report the new paleoparasitologic findings from the examination performed in samples collected in New and Old World archaeological sites. New finds of ancylostomid, Ascaris lumbricoides, Trichuris trichiura, Enterobius vermicularis, Trichostrongylus spp., Diphyllobothrium latum, Hymenolepis nana and Acantocephalan eggs are reported. According to the findings, it is probable that A. lumbricoides was originally a human parasite. Human ancylostomids, A. lumbricoides and T. trichiura, found in the New World in pre-Columbian times, have not been introduced into the Americas by land via Beringia. These parasites could not supported the cold climate of the region. Nomadic prehistoric humans that have crossed the Bering Land Bridge from Asia to the Americas in the last glaciation, probably during generations, would have lost these parasites, which life cycles need warm temperatures in the soil to be transmitted from host to host. Alternative routes are discussed for human parasite introduction into the Americas.

  6. Identification of UDP-glucuronosyltransferase isoforms responsible for leonurine glucuronidation in human liver and intestinal microsomes.

    Science.gov (United States)

    Tan, Bo; Cai, Weimin; Zhang, Jinlian; Zhou, Ning; Ma, Guo; Yang, Ping; Zhu, Qing; Zhu, Yizhun

    2014-09-01

    Leonurine is a potent component of herbal medicine Herba leonuri. The detail information on leonurine metabolism in human has not been revealed so far. Two primary metabolites, leonurine O-glucuronide and demethylated leonurine, were observed and identified in pooled human liver microsomes (HLMs) and O-glucuronide is the predominant one. Among 12 recombinant human UDP-glucuronosyltransferases (UGTs), UGT1A1, UGT1A8, UGT1A9, and UGT1A10 showed catalyzing activity toward leonurine glucuronidation. The intrinsic clearance (CLint) of UGT1A1 was approximately 15-to 20-fold higher than that of UGT1A8, UGT1A9, and UGT1A10, respectively. Both chemical inhibition study and correlation study demonstrated that leonurine glucuronidation activities in HLMs had significant relationship with UGT1A1 activities. Leonurine glucuronide was the major metabolite in human liver microsomes. UGT1A1 was principal enzyme that responsible for leonurine glucuronidation in human liver and intestine microsomes.

  7. Human intestinal circadian clock: expression of clock genes in colonocytes lining the crypt.

    Science.gov (United States)

    Pardini, L; Kaeffer, B; Trubuil, A; Bourreille, A; Galmiche, J-P

    2005-01-01

    Biological clock components have been detected in many epithelial tissues of the digestive tract of mammals (oral mucosa, pancreas, and liver), suggesting the existence of peripheral circadian clocks that may be entrainable by food. Our aim was to investigate the expression of main peripheral clock genes in colonocytes of healthy humans and in human colon carcinoma cell lines. The presence of clock components was investigated in single intact colonic crypts isolated by chelation from the biopsies of 25 patients (free of any sign of colonic lesions) undergoing routine colonoscopy and in cell lines of human colon carcinoma (Caco2 and HT29 clone 19A). Per-1, per-2, and clock mRNA were detected by real-time RT-PCR. The three-dimensional distributions of PER-1, PER-2, CLOCK, and BMAL1 proteins were recorded along colonic crypts by immunofluorescent confocal imaging. We demonstrate the presence of per-1, per-2, and clock mRNA in samples prepared from colonic crypts of 5 patients and in all cell lines. We also demonstrate the presence of two circadian clock proteins, PER-1 and CLOCK, in human colonocytes on crypts isolated from 20 patients (15 patients for PER-1 and 6 for CLOCK) and in colon carcinoma cells. Establishing the presence of clock proteins in human colonic crypts is the first step toward the study of the regulation of the intestinal circadian clock by nutrients and feeding rhythms.

  8. [Computed tomography in endobronchial mucus accumulation].

    Science.gov (United States)

    Gaeta, M; Barone, M; Loria, G; Minutoli, F; Stroscio, S

    1994-01-01

    To investigate the value of CT in depicting endobronchial mucoid collections, the authors retrospectively reviewed the CT scans of 22 patients, 14 with mucous plugs, 7 with mucoid pseudotumors, and one with a bronchocele due to bronchial atresia. Atelectasis could be seen in 11 of 14 patients with mucous plugs. In 12 of 14 patients with mucous plugs CT showed the involved bronchi filled by fluid representing abnormal mucus accumulation. In the patients with atelectasis CT showed mucus-filled bronchi as low-attenuation branching structures (mucoid bronchogram). All the mucoid pseudotumors appeared as low-attenuation (< 20 HU) polypoid wall lesions with no involvement of the bronchial walls. In a patient with bronchial atresia CT showed a solitary pulmonary nodule (representing the obstructed and dilated bronchus filled by mucus) surrounded by peripheral pulmonary hyperinflation. Characteristically, the endobronchial mucoid collections never enhanced after bolus contrast medium. Endobronchial mucoid collections had to be differentiated from endobronchial neoplasms. In some cases bronchoscopy was necessary to make the differential diagnosis. In conclusion, CT is a valuable tool with good sensitivity and specificity in diagnosing endobronchial mucoid collections.

  9. Clinical issues of mucus accumulation in COPD

    Directory of Open Access Journals (Sweden)

    Osadnik CR

    2014-03-01

    Full Text Available Christian R Osadnik,1,2 Christine F McDonald,2,3 Anne E Holland2,4,51Department of Physiotherapy, Monash University, 2Institute for Breathing and Sleep, Austin Health, 3Department of Respiratory and Sleep Medicine, Austin Health, 4Department of Physiotherapy, La Trobe University, 5Department of Physiotherapy, Alfred Health, Melbourne, VIC, AustraliaWe wish to thank Ramos et al for presenting a succinct and up-to-date synthesis of the evidence relating to the important issue of mucus hypersecretion in COPD.1 The authors highlight the association of mucus hypersecretion with poor outcomes, including increased risk of exacerbations, hospitalization and mortality. These associations have led to interest in the potential benefits of mucus clearance techniques in COPD. As Ramos et al1 point out, although the physiological rationale for airway clearance techniques (ACTs in COPD is strong, clinical efficacy has historically been difficult to establish, perhaps due to the variety of techniques and outcomes that have been employed in small studies. We have recently synthesized this body of evidence in a Cochrane systematic review of ACTs for individuals with COPD. The review demonstrated ACTs are safe and meta-analysis showed they confer small beneficial effects on a limited range of important clinical outcomes, such as the need for and duration of ventilatory assistance during an acute exacerbation of COPD (AECOPD.2View original paper by Ramos and colleagues.

  10. Human intestinal microbiota composition is associated with local and systemic inflammation in obesity

    NARCIS (Netherlands)

    Verdam, F.J.; Fuentes Enriquez de Salamanca, S.; Jonge, de C.; Zoetendal, E.G.; Erbil, R.; Greve, J.W.; Buurman, W.A.; Vos, de W.M.; Rensen, S.S.

    2013-01-01

    OBJECTIVE: Intestinal microbiota have been suggested to contribute to the development of obesity, but the mechanism remains elusive. The relationship between microbiota composition, intestinal permeability, and inflammation in nonobese and obese subjects was investigated. DESIGN AND METHODS: Fecal m

  11. Evaluation of impact of exposure of Sudan azo dyes and their metabolites on human intestinal bacteria.

    Science.gov (United States)

    Pan, Hongmiao; Feng, Jinhui; He, Gui-Xin; Cerniglia, Carl E; Chen, Huizhong

    2012-08-01

    Sudan azo dyes are banned for food usage in most countries, but they are illegally used to maintain or enhance the color of food products due to low cost, bright staining, and wide availability of the dyes. In this report, we examined the toxic effects of these azo dyes and their potential reduction metabolites on 11 prevalent human intestinal bacterial strains. Among the tested bacteria, cell growth of 2, 3, 5, 5, and 1 strains was inhibited by Sudan I, II, III, IV, and Para Red, respectively. At the tested concentration of 100 μM, Sudan I and II inhibited growth of Clostridium perfringens and Lactobacillus rhamnosus with decrease of growth rates from 14 to 47%. Sudan II also affected growth of Enterococcus faecalis. Growth of Bifidobacterium catenulatum, C. perfringens, E. faecalis, Escherichia coli, and Peptostreptococcus magnus was affected by Sudan III and IV with decrease in growth rates from 11 to 67%. C. perfringens was the only strain in which growth was affected by Para Red with 47 and 26% growth decreases at 6 and 10 h, respectively. 1-Amino-2-naphthol, a common metabolite of the dyes, was capable of inhibiting growth of most of the tested bacteria with inhibition rates from 8 to 46%. However, the other metabolites of the dyes had no effect on growth of the bacterial strains. The dyes and their metabolites had less effect on cell viability than on cell growth of the tested bacterial strains. Clostridium indolis and Clostridium ramosum were the only two strains with about a 10 % decrease in cell viability in the presence of Sudan azo dyes. The present results suggested that Sudan azo dyes and their metabolites potentially affect the human intestinal bacterial ecology by selectively inhibiting some bacterial species, which may have an adverse effect on human health.

  12. SREBP-2 negatively regulates FXR-dependent transcription of FGF19 in human intestinal cells.

    Science.gov (United States)

    Miyata, Masaaki; Hata, Tatsuya; Yamazoe, Yasushi; Yoshinari, Kouichi

    2014-01-10

    Sterol regulatory element-binding protein-2 (SREBP-2) is a basic helix-loop-helix-leucine zipper transcription factor that positively regulates transcription of target genes involved in cholesterol metabolism. In the present study, we have investigated a possible involvement of SREBP-2 in human intestinal expression of fibroblast growth factor (FGF)19, which is an endocrine hormone involved in the regulation of lipid and glucose metabolism. Overexpression of constitutively active SREBP-2 decreased FGF19 mRNA levels in human colon-derived LS174T cells. In reporter assays, active SREBP-2 overexpression suppressed GW4064/FXR-mediated increase in reporter activities in regions containing the IR-1 motif (+848 to +5200) in the FGF19 gene. The suppressive effect disappeared in reporter activities in the region containing the IR-1 motif when the mutation was introduced into the IR-1 motif. In electrophoretic mobility shift assays, binding of the FXR/retinoid X receptor α heterodimer to the IR-1 motif was attenuated by adding active SREBP-2, but SREBP-2 binding to the IR-1 motif was not observed. In chromatin immunoprecipitation assays, specific binding of FXR to the IR-1-containing region of the FGF19 gene (+3214 to +3404) was increased in LS174T cells by treatment with cholesterol and 25-hydroxycholesterol. Specific binding of SREBP-2 to FXR was observed in glutathione-S-transferase (GST) pull-down assays. These results suggest that SREBP-2 negatively regulates the FXR-mediated transcriptional activation of the FGF19 gene in human intestinal cells.

  13. Supersaturation and Precipitation of Posaconazole Upon Entry in the Upper Small Intestine in Humans.

    Science.gov (United States)

    Hens, Bart; Brouwers, Joachim; Corsetti, Maura; Augustijns, Patrick

    2016-09-01

    The purpose of this study was to explore gastrointestinal dissolution, supersaturation and precipitation of the weakly basic drug posaconazole in humans, and to assess the impact of formulation pH and type on these processes. In a cross-over study, two posaconazole suspensions (40 mg dispersed in 240 mL water at pH 1.6 and pH 7.1, respectively) were intragastrically administered; subsequently, gastric and duodenal fluids were aspirated. In parallel, blood samples were collected. Additionally, posaconazole was intragastrically administered as a solution (20 mg in 240 mL water, pH 1.6). When posaconazole was administered as an acidified suspension, supersaturated duodenal concentrations of posaconazole were observed for approximately 45 min. However, extensive intestinal precipitation was observed. Administration of the neutral suspension resulted in subsaturated concentrations with a mean duodenal AUC0-120 min and Cmax being approximately twofold lower than for the acidified suspension. The mean plasma AUC0-8 h of posaconazole was also twofold higher following administration of the acidified suspension. Similar to the acidified suspension, significant intestinal precipitation (up to 92%) was observed following intragastric administration of the posaconazole solution. This study demonstrated for the first time the gastrointestinal behavior of a weakly basic drug administered in different conditions, and its impact on systemic exposure.

  14. Intestinal short chain fatty acids and their link with diet and human health

    Directory of Open Access Journals (Sweden)

    David eRios-Covian

    2016-02-01

    Full Text Available The colon is inhabited by a dense population of microorganisms, the so-called gut microbiota, able to ferment carbohydrates and proteins that escape absorption in the small intestine during digestion. This microbiota produces a wide range of metabolites, including short chain fatty acids (SCFA. These compounds are absorbed in the large bowel and are defined as 1-6 carbon volatile fatty acids which can present straight or branched-chain conformation. Their production is influenced by the pattern of food intake and diet-mediated changes in the gut microbiota. SCFA have distinct physiological effects: they contribute to shaping the gut environment, influence the physiology of the colon, they can be used as energy sources by host cells and the intestinal microbiota and they also participate in different host-signalling mechanisms. We summarize the current knowledge about the production of SCFA, including bacterial cross-feedings interactions, and the biological properties of these metabolites with impact on the human health

  15. Transepithelial transport of putrescine across monolayers of the human intestinal epithelial cell line, Caco-2

    Institute of Scientific and Technical Information of China (English)

    Vladan Milovic; Lyudmila Turchanowa; Jurgen Stein; Wolfgang F. Caspary

    2001-01-01

    AIM To study the transepithelial transport characteristics of the polyamine putrescine in human intestinal Caco-2 cell monolayers to elucidate the mechanisms of the putrescine intestinal absorption.METHODS The transepithelial transport and the cellular accumulation of putrescine was measured using Caco 2 cell monolayers grown on permeable filters.RESULTS Transepithelial transport of putrescine in physiological concentrations (>0.5 mM)from the apical to basolateral side was linear. Intracellular accumulation of putrescine was higher in confluent than in fully differentiated Caco-2 cells, but still negligible (less than 0.5%) of the overall transport across the monolayers in apical-to-basolateral direction. EGF enhanced putrescine accumulation in Caco-2 cells by four-fold, as well as putrescine conversion to spermidine and spermine by enhancing the activity of Sadenosylmethionine decarboxylase. However,EGF did not have any significant influence on putrescine flux across the Caco-2 cell monolayers. Excretion of putrescine from Caco-2cells into the basolateral medium did not exceed 50 picomoles, while putrescine passive flux from the apical to the basolateral chamber,contributed hundreds of micromoles polyamines to the basolateral chamber.CONCLUSION Transepithelial transport of putrescine across Caco-2 cell monolayers occurs in passive diffusion, and is not influenced when epithelial cells are stimulated to proliferate by a potent mitogen such as EGF.

  16. Glutamine and recombinant human growth hormone protect intestinal barrier function following portal hypertension surgery

    Institute of Scientific and Technical Information of China (English)

    Zhao-Feng Tang; Yun-Biao Ling; Nan Lin; Zheng Hao; Rui-Yun Xu

    2007-01-01

    AIM: To evaluate the effects of combined treatment of glutamine (Gln) and recombinant human growth hormone(rhGH) on intestinal barrier function following portal hypertension surgery.METHODS: This study was designed as a prospective,randomized and controlled clinical trial. Forty two patients after portal hypertension surgery were randomly assigned into 2 groups: control group (n = 20) and supplemental group (adding Gin and rhGH, n = 22). Every patient received isocaloric and isonitrogenous standard total parenteral nutrition (TPN) starting 3 d after surgery for 7 d. Blood samples were obtained before surgery and at the 3rd and 10th day postoperatively. Host immunity was evaluated by measuring levels of CD4, CD8, CD4/CD8, IgG, IgM and IgA, and the inflammatory responses were determined by assessing IL-2, TNF-α and C-reactive protein (CRP) levels. Intestinal permeability and integrity was evaluated by L/M test and histological examination, respectively.RESULTS: On postoperative d 10, CD4, CD4/CD8, IgG and IL-2 levels in supplemental group were significantly higher than those in control group (33.7 ± 5.5 vs 31.0± 5.4, P < 0.05, (1.17 ± 0.32 vs 1.05 ± 0.15, P < 0.05,13.94 ± 1.09 vs 12.33±1.33, P < 0.05, and 368.12± 59.25 vs 318.12 ± 45.65, P < 0.05, respectively),whereas the increase in serum TNF-α concentration was significantly reduced (41.02 ± 27.56 vs 160.09 ± 35.17,P < 0.05). The increase in L/M ratio was significantly lower in the supplemental group than in the control group (0.0166 ± 0.0017 vs 0.0339 ± 0.0028, P < 0.05).Moreover, mucosal integrity in the supplemental group was better than in the control group.CONCLUSION: Postoperative administration of TPN supplemented with Gin and rhGH in patients after portal hypertension surgery improves immune function,modulates inflammatory response, prevents the intestinal mucous membrane from atrophy and preserves intestinal integrity.

  17. Cervical mucus properties stratify risk for preterm birth.

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    Agatha S Critchfield

    Full Text Available BACKGROUND: Ascending infection from the colonized vagina to the normally sterile intrauterine cavity is a well-documented cause of preterm birth. The primary physical barrier to microbial ascension is the cervical canal, which is filled with a dense and protective mucus plug. Despite its central role in separating the vaginal from the intrauterine tract, the barrier properties of cervical mucus have not been studied in preterm birth. METHODS AND FINDINGS: To study the protective function of the cervical mucus in preterm birth we performed a pilot case-control study to measure the viscoelasticity and permeability properties of mucus obtained from pregnant women at high-risk and low-risk for preterm birth. Using extensional and shear rheology we found that cervical mucus from women at high-risk for preterm birth was more extensible and forms significantly weaker gels compared to cervical mucus from women at low-risk of preterm birth. Moreover, permeability measurements using fluorescent microbeads show that high-risk mucus was more permeable compared with low-risk mucus. CONCLUSIONS: Our findings suggest that critical biophysical barrier properties of cervical mucus in women at high-risk for preterm birth are compromised compared to women with healthy pregnancy. We hypothesize that impaired barrier properties of cervical mucus could contribute to increased rates of intrauterine infection seen in women with preterm birth. We furthermore suggest that a robust association of spinnbarkeit and preterm birth could be an effectively exploited biomarker for preterm birth prediction.

  18. Transcobalamin derived from bovine milk stimulates apical uptake of vitamin B12 into human intestinal epithelial cells.

    Science.gov (United States)

    Hine, Brad; Boggs, Irina; Green, Ralph; Miller, Joshua W; Hovey, Russell C; Humphrey, Rex; Wheeler, Thomas T

    2014-11-01

    Intestinal uptake of vitamin B12 (hereafter B12) is impaired in a significant proportion of the human population. This impairment is due to inherited or acquired defects in the expression or function of proteins involved in the binding of diet-derived B12 and its uptake into intestinal cells. Bovine milk is an abundant source of bioavailable B12 wherein it is complexed with transcobalamin. In humans, transcobalamin functions primarily as a circulatory protein, which binds B12 following its absorption and delivers it to peripheral tissues via its cognate receptor, CD320. In the current study, the transcobalamin-B12 complex was purified from cows' milk and its ability to stimulate uptake of B12 into cultured bovine, mouse and human cell lines was assessed. Bovine milk-derived transcobalamin-B12 complex was absorbed by all cell types tested, suggesting that the uptake mechanism is conserved across species. Furthermore, the complex stimulated the uptake of B12 via the apical surface of differentiated Caco-2 human intestinal epithelial cells. These findings suggest the presence of an alternative transcobalamin-mediated uptake pathway for B12 in the human intestine other than that mediated by the gastric glycoprotein, intrinsic factor. Our findings highlight the potential for transcobalamin-B12 complex derived from bovine milk to be used as a natural bioavailable alternative to orally administered free B12 to overcome B12 malabsorption.

  19. Identification of glucose-fermenting bacteria present in an in vitro model of the human intestine by RNA-stable isotope probing

    NARCIS (Netherlands)

    Egert, M.; Graaf, A.A. de; Maathuis, A.; Waard, P. de; Plugge, C.M.; Smidt, H.; Deutz, N.E.P.; Dijkema, C.; Vos, W.M. de; Venema, K.

    2007-01-01

    16S rRNA-based stable isotope probing (SIP) and nuclear magnetic resonance (NMR) spectroscopy-based metabolic profiling were used to identify bacteria fermenting glucose under conditions simulating the human intestine. The TIM-2 in vitro model of the human intestine was inoculated with a GI tract mi

  20. Cooperation between MEF2 and PPARγ in human intestinal β,β-carotene 15,15'-monooxygenase gene expression

    Directory of Open Access Journals (Sweden)

    Yan Bingfang

    2006-02-01

    Full Text Available Abstract Background Vitamin A and its derivatives, the retinoids, are essential for normal embryonic development and maintenance of cell differentiation. β, β-carotene 15,15'-monooxygenase 1 (BCMO1 catalyzes the central cleavage of β-carotene to all-trans retinal and is the key enzyme in the intestinal metabolism of carotenes to vitamin A. However, human and various rodent species show markedly different efficiencies in intestinal BCMO1-mediated carotene to retinoid conversion. The aim of this study is to identify potentially human-specific regulatory control mechanisms of BCMO1 gene expression. Results We identified and functionally characterized the human BCMO1 promoter sequence and determined the transcriptional regulation of the BCMO1 gene in a BCMO1 expressing human intestinal cell line, TC-7. Several functional transcription factor-binding sites were identified in the human promoter that are absent in the mouse BCMO1 promoter. We demonstrate that the proximal promoter sequence, nt -190 to +35, confers basal transcriptional activity of the human BCMO1 gene. Site-directed mutagenesis of the myocyte enhancer factor 2 (MEF2 and peroxisome proliferator-activated receptor (PPAR binding elements resulted in decreased basal promoter activity. Mutation of both promoter elements abrogated the expression of intestinal cell BCMO1. Electrophoretic mobility shift and supershift assays and transcription factor co-expression in TC-7 cells showed MEF2C and PPARγ bind to their respective DNA elements and synergistically transactivate BCMO1 expression. Conclusion We demonstrate that human intestinal cell BCMO1 expression is dependent on the functional cooperation between PPARγ and MEF2 isoforms. The findings suggest that the interaction between MEF2 and PPAR factors may provide a molecular basis for interspecies differences in the transcriptional regulation of the BCMO1 gene.

  1. Vasoactive intestinal polypeptide and peptide histidine methionine. Presence in human follicular fluid and effects on DNA synthesis and steroid secretion in cultured human granulosa/lutein cells

    DEFF Research Database (Denmark)

    Gräs, S; Ovesen, P; Andersen, A N;

    1994-01-01

    Vasoactive intestinal polypeptide (VIP) and peptide histidine methionine (PHM) originate from the same precursor molecule, prepro VIP. In the present study we examined the concentrations of VIP and PHM in human follicular fluid and their effects on cultured human granulosa/lutein cells. Follicular...

  2. Studies with inulin-type fructans on intestinal infections, permeability, and inflammation.

    Science.gov (United States)

    Guarner, Francisco

    2007-11-01

    Symbiosis between host and gut bacteria can be optimized by prebiotics. Inulin-type fructans have been shown to improve the microbial balance of the intestinal ecosystem by stimulating the growth of bifidobacteria and lactobacilli. These changes have been associated with several health benefits, including the prevention of gastrointestinal and systemic infections in animal models and human studies. Inulin-type fructans induce changes of the intestinal mucosa characterized by higher villi, deeper crypts, increased number of goblet cells, and a thicker mucus layer on the colonic epithelium. Bacterial antagonism and competition of bifidobacteria and lactobacilli with pathogens, as well as the trophic effects on the intestinal epithelium, may explain the protective role of inulin against enteric infections. In contrast, studies with rats fed a low-calcium diet suggested a negative effect of prebiotics on intestinal barrier function. However, the adverse effect was clearly ascribed to the strong reduction of dietary calcium, as it could be reversed by oral administration of calcium. The adverse effect of a low-calcium diet on intestinal permeability has not been observed in humans. Inulin and oligofructose are now being tested in human studies aimed at prevention of bacterial translocation in critical health conditions. Mixtures of probiotics and prebiotics including inulin or oligofructose significantly reduced the rate of postoperative infections in liver transplant patients. Finally, inulin and oligofructose have proven useful to prevent mucosal inflammatory disorders in animal models and in patients with inflammatory bowel disease.

  3. CONTROL AND CANCEROUS TISSUES OF HUMAN STOMACH, SMALL INTESTINE AND LARGE INTESTINE - THE AVERAGE CONTENT OF SODIUM AND POTASSIUM

    Directory of Open Access Journals (Sweden)

    Marta Głogowska

    2015-02-01

    Full Text Available Sodium and potassium regulate the total amount of water in the body and the transmission of sodium into and out of individual cells also plays a role in critical body functions. The movement of sodium is critical in generation of these electrical signals. Research was conducted on samples taken from women and men aged 20-90 years, derived from the stomach, small intestine and large intestine. Samples were dried at 80ºC for 24 hours, and then increased temperature to 105ºC and dried for seven days until dry mass was obtained. All dry material of each sample was weighted and placed in a separate mineralization tubes and mixed with 1 cm3 of 65% HNO3 and heated at 105°C for 120 minutes in a thermostat-controlled digestion block, VELP Scientifica DK 20. Metals such as sodium and potassium were detected using FAAS method. The average content of sodium in patients diagnosed with stomach cancer is lower, than in healthy person. Indicate higher mean content of sodium in the control tissues of stomach (2151,730 μg•g-1d.m., compared to a sodium content in tissues adjacent to the tumor (1813,958 μg•g-1d.m. and tumor tissues (2029,442 μg•g-1d.m.. In the case of colon, control tissues have lower average content of sodium (2160,886 μg•g-1d.m., than the tissues surrounding the tumor (3325,963 μg•g-1d.m. and tumor tissues (3037,121 μg•g-1d.m.. The potassium level is higher in the control tissues of stomach (1428,993 μg•g-1d.m., than in the tissues adjacent to the tumor (1091,544 μg•g-1d.m. and tumor tissues (1220,471 μg•g-1d.m.. In the large intestine higher average content of potassium is characterized by tumor tissues (2307,234 μg•g-1d.m. and tissues adjacent to the tumor (1712,779 μg•g-1d.m., than control tissue (1389,703 μg•g-1d.m.. Comparing this relationship with data on potassium channels, it can be assumed that in the some case of malignant transformation in the colon, potassium channels also play a big role.

  4. Bile Salt Micelles and Phospholipid Vesicles Present in Simulated and Human Intestinal Fluids

    DEFF Research Database (Denmark)

    Elvang, Philipp A; Hinna, Askell H; Brouwers, Joachim

    2016-01-01

    Knowledge about colloidal assemblies present in human intestinal fluids (HIFs), such as bile salt micelles and phospholipid vesicles, is regarded of importance for a better understanding of the in vivo dissolution and absorption behavior of poorly soluble drugs (Biopharmaceutics Classification...... distinct size fraction of colloidal assemblies, whereas FeSSIF contained 2 fractions of colloidal species with significantly different sizes. These size fractions likely represent (1) mixed taurocholate-phospholipid-micelles, as indicated by a size range up to 70 nm (in diameter) and a strong UV absorption...... sizes of approximately 50 and 200 nm, respectively (intensity-weighted mean diameter, Dz), likely representing mixed cholate/phospholipid micelles and phospholipid vesicles, respectively. The sizes of the smaller 2 fractions being below the size range of multiangle laser light scattering analysis (

  5. Localization of ABCG5 and ABCG8 proteins in human liver, gall bladder and intestine

    Directory of Open Access Journals (Sweden)

    Chavin Kenneth D

    2004-09-01

    Full Text Available Abstract Background The molecular mechanisms that regulate the entry of dietary sterols into the body and their removal via hepatobiliary secretion are now beginning to be defined. These processes are specifically disrupted in the rare autosomal recessive disease, Sitosterolemia (MIM 210250. Mutations in either, but not both, of two genes ABCG5 or ABCG8, comprising the STSL locus, are now known to cause this disease and their protein products are proposed to function as heterodimers. Under normal circumstances cholesterol, but not non-cholesterol sterols, is preferentially absorbed from the diet. Additionally, any small amounts of non-cholesterol sterols that are absorbed are rapidly taken up by the liver and preferentially excreted into bile. Based upon the defects in sitosterolemia, ABCG5 and ABCG8 serve specifically to exclude non-cholesterol sterol entry at the intestinal level and are involved in sterol excretion at the hepatobiliary level. Methods Here we report the biochemical and immuno-localization of ABCG5 and ABCG8 in human liver, gallbladder and intestine using cell fractionation and immunohistochemical analyses. Results We raised peptide antibodies against ABCG5 and ABCG8 proteins. Using human liver samples, cell fractionation studies showed both proteins are found in membrane fractions, but they did not co-localize with caveolin-rafts, ER, Golgi or mitochondrial markers. Although their distribution in the sub-fractions was similar, they were not completely contiguous. Immunohistochemical analyses showed that while both proteins were readily detectable in the liver, ABCG5 was found predominately lining canalicular membranes, whereas ABCG8 was found in association with bile duct epithelia. At the cellular level, ABCG5 appeared to be apically expressed, whereas ABCG8 had a more diffuse expression pattern. Both ABCG5 and ABCG8 appeared to localize apically as shown by co-localization with MRP2. The distribution patterns of ABCG5 and

  6. Ultrastructure of interstitial cells of Cajal associated with deep muscular plexus of human small intestine

    DEFF Research Database (Denmark)

    Rumessen, J J; Mikkelsen, H B; Thuneberg, L

    1992-01-01

    a continuous basal lamina, caveolae, intermediate filaments, dense bodies, dense bands, and a well-developed subsurface smooth endoplasmic reticulum), but the arrangement of organelles was clearly different, and cisternae of granular endoplasmic reticulum were abundant. Interstitial cells of Cajal were......Evidence showing that interstitial cells of Cajal have important regulatory functions in the gut musculature is accumulating. In the current study, the ultrastructure of the deep muscular plexus and associated interstial cells of Cajal in human small intestine were studied to provide a reference...... for identification and further physiological or pathological studies. The deep muscular plexus was sandwiched between a thin inner layer of smooth muscle (one to five cells thick) and the bulk of the circular muscle. Interstitial cells of Cajal in this region very much resembled smooth muscle cells (with...

  7. Conformational restrictions in ligand binding to the human intestinal di-/tripeptide transporter

    DEFF Research Database (Denmark)

    Våbenø, Jon; Nielsen, Carsten Uhd; Steffansen, Bente

    2005-01-01

    by conformational analysis and 2D dihedral driving analysis of 15 hPEPT1 substrates, which suggested that psi(1) approximately 165 degrees , omega(1) approximately 180 degrees , and phi(2) approximately 280 degrees were descriptive of the bioactive conformation. Subsequently, the conformational energy required......The aim of the present study was to develop a computational method aiding the design of dipeptidomimetic pro-moieties targeting the human intestinal di-/tripeptide transporter hPEPT1. First, the conformation in which substrates bind to hPEPT1 (the bioactive conformation) was identified...... to change the peptide backbone conformation (DeltaE(bbone)) from the global energy minimum conformation to the identified bioactive conformation was calculated for 20 hPEPT1 targeted model prodrugs with known K(i) values. Quantitatively, an inverse linear relationship (r(2)=0.81, q(2)=0.80) was obtained...

  8. Activation of Intestinal Human Pregnane X Receptor Protects against Azoxymethane/Dextran Sulfate Sodium–Induced Colon Cancer

    Science.gov (United States)

    Cheng, Jie; Fang, Zhong-Ze; Nagaoka, Kenjiro; Okamoto, Minoru; Qu, Aijuan; Tanaka, Naoki; Kimura, Shioko

    2014-01-01

    The role of intestinal human pregnane X receptor (PXR) in colon cancer was determined through investigation of the chemopreventive role of rifaximin, a specific agonist of intestinal human PXR, toward azoxymethane (AOM)/dextran sulfate sodium (DSS)–induced colon cancer. Rifaximin treatment significantly decreased the number of colon tumors induced by AOM/DSS treatment in PXR-humanized mice, but not wild-type or Pxr-null mice. Additionally, rifaximin treatment markedly increased the survival rate of PXR-humanized mice, but not wild-type or Pxr-null mice. These data indicated a human PXR–dependent therapeutic chemoprevention of rifaximin toward AOM/DSS-induced colon cancer. Nuclear factor κ-light-chain-enhancer of activated B cells–mediated inflammatory signaling was upregulated in AOM/DSS-treated mice, and inhibited by rifaximin in PXR-humanized mice. Cell proliferation and apoptosis were also modulated by rifaximin treatment in the AOM/DSS model. In vitro cell-based assays further revealed that rifaximin regulated cell apoptosis and cell cycle in a human PXR-dependent manner. These results suggested that specific activation of intestinal human PXR exhibited a chemopreventive role toward AOM/DSS-induced colon cancer by mediating anti-inflammation, antiproliferation, and proapoptotic events. PMID:25277138

  9. Activation of intestinal human pregnane X receptor protects against azoxymethane/dextran sulfate sodium-induced colon cancer.

    Science.gov (United States)

    Cheng, Jie; Fang, Zhong-Ze; Nagaoka, Kenjiro; Okamoto, Minoru; Qu, Aijuan; Tanaka, Naoki; Kimura, Shioko; Gonzalez, Frank J

    2014-12-01

    The role of intestinal human pregnane X receptor (PXR) in colon cancer was determined through investigation of the chemopreventive role of rifaximin, a specific agonist of intestinal human PXR, toward azoxymethane (AOM)/dextran sulfate sodium (DSS)-induced colon cancer. Rifaximin treatment significantly decreased the number of colon tumors induced by AOM/DSS treatment in PXR-humanized mice, but not wild-type or Pxr-null mice. Additionally, rifaximin treatment markedly increased the survival rate of PXR-humanized mice, but not wild-type or Pxr-null mice. These data indicated a human PXR-dependent therapeutic chemoprevention of rifaximin toward AOM/DSS-induced colon cancer. Nuclear factor κ-light-chain-enhancer of activated B cells-mediated inflammatory signaling was upregulated in AOM/DSS-treated mice, and inhibited by rifaximin in PXR-humanized mice. Cell proliferation and apoptosis were also modulated by rifaximin treatment in the AOM/DSS model. In vitro cell-based assays further revealed that rifaximin regulated cell apoptosis and cell cycle in a human PXR-dependent manner. These results suggested that specific activation of intestinal human PXR exhibited a chemopreventive role toward AOM/DSS-induced colon cancer by mediating anti-inflammation, antiproliferation, and proapoptotic events.

  10. Increased levels of mucins in the cystic fibrosis mouse small intestine, and modulator effects of the Muc1 mucin expression.

    Science.gov (United States)

    Malmberg, Emily K; Noaksson, Karin A; Phillipson, Mia; Johansson, Malin E V; Hinojosa-Kurtzberg, Marina; Holm, Lena; Gendler, Sandra J; Hansson, Gunnar C

    2006-08-01

    The mouse model (Cftr(tm1UNC)/Cftr(tm1UNC)) for cystic fibrosis (CF) shows mucus accumulation and increased Muc1 mucin mRNA levels due to altered splicing (Hinojosa-Kurtzberg AM, Johansson MEV, Madsen CS, Hansson GC, and Gendler SJ. Am J Physiol Gastrointest Liver Physiol 284: G853-G862, 2003). However, it is not known whether Muc1 is a major mucin contributing to the increased mucus and why CF/Muc1-/- mice show lower mucus accumulation. To address this, we have purified mucins from the small intestine of CF mice using guanidinium chloride extraction, ultracentrifugation, and gel filtration and analyzed them by slot blot, gel electrophoresis, proteomics, and immunoblotting. Normal and CF mice with wild-type (WT) Muc1 or Muc1-/- or that are transgenic for human MUC1 (MUC1.Tg, on a Muc1-/- background) were analyzed. The total amount of mucins, both soluble and insoluble in guanidinium chloride, increased up to 10-fold in the CF mice compared with non-CF animals, whereas the CF mice lacking Muc1 showed intermediate levels between the CF and non-CF mice. However, the levels of Muc3 (orthologue of human MUC17) were increased in the CF/Muc1-/- mice compared with the CF/MUC1.Tg animals. The amount of MUC1 mucin was increased several magnitudes in the CF mice, but MUC1 did still not appear to be a major mucin. The amount of insoluble mucus of the large intestine was also increased in the CF mice, an effect that was partially restored in the CF/Muc1-/- mice. The thickness of the firmly adherent mucus layer of colon in the Muc1-/- mice was significantly lower than that of WT mice. The results suggest that MUC1 is not a major component in the accumulated mucus of CF mice and that MUC1 can influence the amount of other mucins in a still unknown way.

  11. Innervation of enteric mast cells by primary spinal afferents in guinea pig and human small intestine.

    Science.gov (United States)

    Wang, Guo-Du; Wang, Xi-Yu; Liu, Sumei; Qu, Meihua; Xia, Yun; Needleman, Bradley J; Mikami, Dean J; Wood, Jackie D

    2014-10-01

    Mast cells express the substance P (SP) neurokinin 1 receptor and the calcitonin gene-related peptide (CGRP) receptor in guinea pig and human small intestine. Enzyme-linked immunoassay showed that activation of intramural afferents by antidromic electrical stimulation or by capsaicin released SP and CGRP from human and guinea pig intestinal segments. Electrical stimulation of the afferents evoked slow excitatory postsynaptic potentials (EPSPs) in the enteric nervous system. The slow EPSPs were mediated by tachykinin neurokinin 1 and CGRP receptors. Capsaicin evoked slow EPSP-like responses that were suppressed by antagonists for protease-activated receptor 2. Afferent stimulation evoked slow EPSP-like excitation that was suppressed by mast cell-stabilizing drugs. Histamine and mast cell protease II were released by 1) exposure to SP or CGRP, 2) capsaicin, 3) compound 48/80, 4) elevation of mast cell Ca²⁺ by ionophore A23187, and 5) antidromic electrical stimulation of afferents. The mast cell stabilizers cromolyn and doxantrazole suppressed release of protease II and histamine when evoked by SP, CGRP, capsaicin, A23187, electrical stimulation of afferents, or compound 48/80. Neural blockade by tetrodotoxin prevented mast cell protease II release in response to antidromic electrical stimulation of mesenteric afferents. The results support a hypothesis that afferent innervation of enteric mast cells releases histamine and mast cell protease II, both of which are known to act in a diffuse paracrine manner to influence the behavior of enteric nervous system neurons and to elevate the sensitivity of spinal afferent terminals.

  12. Transport of Aflatoxin M1 in human intestinal Caco-2/TC7 cells

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    Francesca eCaloni

    2012-06-01

    Full Text Available Aflatoxin M1 (AFM1 is a hydroxylated metabolite of aflatoxin B1 (AFB1. After it is formed, it is secreted in the milk of mammals.Despite the potential risk of human exposure to AFM1, data reported in literature on the metabolism, toxicity and bioavailability of this molecule are limited and out of date. The aim of the present research was to study the absorption profile of AFM1 and possible damage to tight junctions of the intestinal Caco-2/TC7 clone grown on microporous filter supports. These inserts allowed for the separation of the apical and basolateral compartments which correspond to the in vivo lumen and the interstitial space/vascular systems of intestinal mucosa respectively.In this study, the Caco-2/TC7 cells were treated with different AFM1 concentrations (10-10,000 ng/kg for short (40 minutes and long periods of time (48 hours. The AFM1 influx/efflux transport and effects on tight junctions were evaluated by measuring trans-epithelial electrical resistance and observing tight junction protein (Zonula occludens-1 and occludin localization.The results showed that: i when introduced to the apical and basolateral compartments, AFM1 was poorly absorbed by the Caco-2/TC7 cells but its transport across the cell monolayer occurred very quickly (Papp value of 105.10 ± 7.98 cm/s x 10-6. ii The integrity of tight junctions was not permanently compromised after exposure to the mycotoxin. Viability impairment or barrier damage did not occur either.The present results contribute to the evaluation of human risk exposure to AFM1, although the AFM1 transport mechanism need to be clarified.

  13. The Nucleotide Synthesis Enzyme CAD Inhibits NOD2 Antibacterial Function in Human Intestinal Epithelial Cells

    Science.gov (United States)

    Richmond, Amy L.; Kabi, Amrita; Homer, Craig R.; García, Noemí Marina; Nickerson, Kourtney P.; NesvizhskiI, Alexey I.; Sreekumar, Arun; Chinnaiyan, Arul M.; Nuñez, Gabriel; McDonald, Christine

    2013-01-01

    BACKGROUND & AIMS Polymorphisms that reduce the function of nucleotide-binding oligomerization domain (NOD)2, a bacterial sensor, have been associated with Crohn’s disease (CD). No proteins that regulate NOD2 activity have been identified as selective pharmacologic targets. We sought to discover regulators of NOD2 that might be pharmacologic targets for CD therapies. METHODS Carbamoyl phosphate synthetase/ aspartate transcarbamylase/dihydroorotase (CAD) is an enzyme required for de novo pyrimidine nucleotide synthesis; it was identified as a NOD2-interacting protein by immunoprecipitation-coupled mass spectrometry. CAD expression was assessed in colon tissues from individuals with and without inflammatory bowel disease by immunohistochemistry. The interaction between CAD and NOD2 was assessed in human HCT116 intestinal epithelial cells by immunoprecipitation, immunoblot, reporter gene, and gentamicin protection assays. We also analyzed human cell lines that express variants of NOD2 and the effects of RNA interference, overexpression and CAD inhibitors. RESULTS CAD was identified as a NOD2-interacting protein expressed at increased levels in the intestinal epithelium of patients with CD compared with controls. Overexpression of CAD inhibited NOD2-dependent activation of nuclear factor κB and p38 mitogen-activated protein kinase, as well as intracellular killing of Salmonella. Reduction of CAD expression or administration of CAD inhibitors increased NOD2-dependent signaling and antibacterial functions of NOD2 variants that are and are not associated with CD. CONCLUSIONS The nucleotide synthesis enzyme CAD is a negative regulator of NOD2. The antibacterial function of NOD2 variants that have been associated with CD increased in response to pharmacologic inhibition of CAD. CAD is a potential therapeutic target for CD. PMID:22387394

  14. Enterohemorrhagic Escherichia coli induce attaching and effacing lesions and hemorrhagic colitis in human and bovine intestinal xenograft models

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    Lilach Golan

    2011-01-01

    Enterohemorrhagic Escherichia coli (EHEC O157:H7 is an important cause of diarrhea, hemorrhagic colitis and hemolytic uremic syndrome in humans worldwide. The two major virulence determinants of EHEC are the Shiga toxins (Stx and the type III secretion system (T3SS, including the injected effectors. Lack of a good model system hinders the study of EHEC virulence. Here, we investigated whether bovine and human intestinal xenografts in SCID mice can be useful for studying EHEC and host tissue interactions. Fully developed, germ-free human and bovine small intestine and colon were established by subcutaneous transplantation of human and bovine fetal gut into SCID mice. Xenografts were allowed to develop for 3–4 months and thereafter were infected by direct intraluminal inoculation of Stx-negative derivatives of EHEC O157:H7, strain EDL933. The small intestine and colon xenografts closely mimicked the respective native tissues. Upon infection, EHEC induced formation of typical attaching and effacing lesions and tissue damage that resembled hemorrhagic colitis in colon xenografts. By contrast, xenografts infected with an EHEC mutant deficient in T3SS remained undamaged. Furthermore, EHEC did not attach to or damage the epithelium of small intestinal tissue, and these xenografts remained intact. EHEC damaged the colon in a T3SS-dependent manner, and this model is therefore useful for studying the molecular details of EHEC interactions with live human and bovine intestinal tissue. Furthermore, we demonstrate that Stx and gut microflora are not essential for EHEC virulence in the human gut.

  15. Hepatic-intestinal disposal of endogenous human alpha atrial natriuretic factor99-126 in patients with cirrhosis

    DEFF Research Database (Denmark)

    Henriksen, Jens Henrik; Bendtsen, Flemming; Schütten, H J

    1990-01-01

    Hepatic-intestinal disposal of endogenous human alpha atrial natriuretic factor99-126 (ANF) was assessed in 13 patients with cirrhosis (six Child-Turcotte class A, five class B, and two class C) and eight control subjects. The Fick principle was applied during hepatic vein catheterization. Arterial...

  16. A comparative analysis of the intestinal metagenomes present in guinea pigs (Cavia porcellus) and humans (Homo sapiens)

    DEFF Research Database (Denmark)

    Hildebrand, Falk; Ebersbach, Tine; Nielsen, Henrik Bjørn

    2012-01-01

    Background: Guinea pig (Cavia porcellus) is an important model for human intestinal research. We have characterized the faecal microbiota of 60 guinea pigs using Illumina shotgun metagenomics, and used this data to compile a gene catalogue of its prevalent microbiota. Subsequently, we compared th...

  17. Hepatic-intestinal disposal of endogenous human alpha atrial natriuretic factor99-126 in patients with cirrhosis

    DEFF Research Database (Denmark)

    Henriksen, Jens Henrik Sahl; Bendtsen, F; Schütten, H J

    1990-01-01

    Hepatic-intestinal disposal of endogenous human alpha atrial natriuretic factor99-126 (ANF) was assessed in 13 patients with cirrhosis (six Child-Turcotte class A, five class B, and two class C) and eight control subjects. The Fick principle was applied during hepatic vein catheterization. Arterial...

  18. Comparative analysis of pyrosequencing and a phylogenetic microarray for exploring microbial community structures in the human distal intestine

    NARCIS (Netherlands)

    Claesson, M.J.; O'Sullivan, O.; Wang, Q.; Nikkilä, J.; Marchesi, J.R.; Smidt, H.; Vos, de W.M.; Ross, R.P.; O'Toole, P.W.

    2009-01-01

    BACKGROUND: Variations in the composition of the human intestinal microbiota are linked to diverse health conditions. High-throughput molecular technologies have recently elucidated microbial community structure at much higher resolution than was previously possible. Here we compare two such methods

  19. Carboxylated nanodiamonds are neither cytotoxic nor genotoxic on liver, kidney, intestine and lung human cell lines.

    Science.gov (United States)

    Paget, V; Sergent, J A; Grall, R; Altmeyer-Morel, S; Girard, H A; Petit, T; Gesset, C; Mermoux, M; Bergonzo, P; Arnault, J C; Chevillard, S

    2014-08-01

    Although nanodiamonds (NDs) appear as one of the most promising nanocarbon materials available so far for biomedical applications, their risk for human health remains unknown. Our work was aimed at defining the cytotoxicity and genotoxicity of two sets of commercial carboxylated NDs with diameters below 20 and 100 nm, on six human cell lines chosen as representative of potential target organs: HepG2 and Hep3B (liver), Caki-1 and Hek-293 (kidney), HT29 (intestine) and A549 (lung). Cytotoxicity of NDs was assessed by measuring cell impedance (xCELLigence® system) and cell survival/death by flow cytometry while genotoxicity was assessed by γ-H2Ax foci detection, which is considered the most sensitive technique for studying DNA double-strand breaks. To validate and check the sensitivity of the techniques, aminated polystyrene nanobeads were used as positive control in all assays. Cell incorporation of NDs was also studied by flow cytometry and luminescent N-V center photoluminescence (confirmed by Raman microscopy), to ensure that nanoparticles entered the cells. Overall, we show that NDs effectively entered the cells but NDs do not induce any significant cytotoxic or genotoxic effects on the six cell lines up to an exposure dose of 250 µg/mL. Taken together these results strongly support the huge potential of NDs for human nanomedicine but also their potential as negative control in nanotoxicology studies.

  20. Alteration of a human intestinal microbiota under extreme life environment in the Antarctica.

    Science.gov (United States)

    Jin, Jong-Sik; Touyama, Mutsumi; Yamada, Shin; Yamazaki, Takashi; Benno, Yoshimi

    2014-01-01

    The human intestinal microbiota (HIM) settles from birth and continues to change phenotype by some factors (e.g. host's diet) throughout life. However, the effect of extreme life environment on human HIM composition is not well known. To understand HIM fluctuation under extreme life environment in humans, fecal samples were collected from six Japanese men on a long Antarctic expedition. They explored Antarctica for 3 months and collected their fecal samples at once-monthly intervals. Using terminal restriction fragment length polymorphism (T-RFLP) and real time polymerase chain reaction (PCR) analysis, the composition of HIM in six subjects was investigated. Three subjects presented restoration of HIM after the expedition compared versus before and during the expedition. Two thirds samples collected during the expedition belonged to the same cluster in dendrogram. However, all through the expedition, T-RFLP patterns showed interindividual variability. Especially, Bifidobacterium spp. showed a tendency to decrease during and restore after the expedition. A reduction of Bifidobacterium spp. was observed in five subjects the first 1 month of the expedition. Bacteroides thetaiotaomicron, which is thought to proliferate during emotional stress, significantly decreased in one subject, indicating that other factors in addition to emotional stress may affect the composition of HIM in this study. These findings could be helpful to understand the effect of extreme life environment on HIM.

  1. Streptococcal Adhesin P (SadP) contributes to Streptococcus suis adhesion to the human intestinal epithelium

    Science.gov (United States)

    Ferrando, Maria Laura; Willemse, Niels; Zaccaria, Edoardo; Pannekoek, Yvonne; van der Ende, Arie; Schultsz, Constance

    2017-01-01

    Background Streptococcus suis is a zoonotic pathogen, causing meningitis and septicemia. We previously demonstrated that the gastrointestinal tract (GIT) is an entry site for zoonotic S. suis infection. Here we studied the contribution of Streptococcal adhesin Protein (SadP) to host-pathogen interaction at GIT level. Methods SadP expression in presence of Intestinal Epithelial Cells (IEC) was compared with expression of other virulence factors by measuring transcript levels using quantitative Real Time PCR (qRT-PCR). SadP variants were identified by phylogenetic analysis of complete DNA sequences. The interaction of SadP knockout and complementation mutants with IEC was tested in vitro. Results Expression of sadP was significantly increased in presence of IEC. Sequence analysis of 116 invasive strains revealed five SadP sequence variants, correlating with genotype. SadP1, present in zoonotic isolates of clonal complex 1, contributed to binding to both human and porcine IEC and translocation across human IEC. Antibodies against the globotriaosylceramide Gb3/CD77 receptor significantly inhibited adhesion to human IEC. Conclusion SadP is involved in the host-pathogen interaction in the GIT. Differences between SadP variants may determine different affinities to the Gb3/CD77 host-receptor, contributing to variation in adhesion capacity to host IEC and thus to S. suis zoonotic potential. PMID:28407026

  2. BCFA suppresses LPS induced IL-8 mRNA expression in human intestinal epithelial cells.

    Science.gov (United States)

    Yan, Y; Wang, Z; Greenwald, J; Kothapalli, K S D; Park, H G; Liu, R; Mendralla, E; Lawrence, P; Wang, X; Brenna, J T

    2017-01-01

    Branched chain fatty acids (BCFA) are components of common food fats and are major constituents of the normal term human newborn GI tract. Polyunsaturated fatty acids (PUFA) have been suggested to reduce the risk and development of inflammatory bowel diseases (IBD); however, little is known about the influence of BCFA on inflammation. We investigated the effect of BCFA on interleukin (IL)-8 and NF-κB production in a human intestinal epithelial cell line (Caco-2). Cells were pre-treated with specific BCFA, or DHA, or EPA, and then activated with lipopolysaccharide (LPS). Both anteiso- and iso- BCFA reduce IL-8. Anteiso-BCFA more effectively suppressed IL-8 than iso-BCFA in LPS stimulated Caco-2 cells. However BCFA in general were less effective than DHA or EPA. Activated BCFA-treated cells expressed less of the cell surface Toll-like receptor 4 (TLR-4) compared to controls. These are the first data to show the reduction of pro-inflammatory markers in human cells mediated by BCFA. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. Adherence to and invasion of human intestinal cells by Arcobacter species and their virulence genotypes.

    Science.gov (United States)

    Levican, Arturo; Alkeskas, Aldukali; Günter, Claudia; Forsythe, Stephen J; Figueras, María José

    2013-08-01

    The genus Arcobacter is composed of 17 species which have been isolated from various sources. Of particular interest are A. butzleri, A. cryaerophilus, and A. skirrowii, as these have been associated with human cases of diarrhea, the probable transmission routes being through the ingestion of contaminated drinking water and food. To date, only limited studies of virulence traits in this genus have been undertaken. The present study used 60 Arcobacter strains isolated from different sources, representing 16 of the 17 species of the genus, to investigate their ability to adhere to and invade the human intestinal cell line Caco-2. In addition, the presence of five putative virulence genes (ciaB, cadF, cj1349, hecA, and irgA) was screened for in these strains by PCR. All Arcobacter species except A. bivalviorum and Arcobacter sp. strain W63 adhered to Caco-2 cells, and most species (10/16) were invasive. The most invasive species were A. skirrowii, A. cryaerophilus, A. butzleri, and A. defluvii. All invasive strains were positive for ciaB (encoding a putative invasion protein). Other putative virulence genes were present in other species, i.e., A. butzleri (cadF, cj1349, irgA, and hecA), A. trophiarum (cj1349), A. ellisii (cj1349), and A. defluvii (irgA). No virulence genes were detected in strains which showed little or no invasion of Caco-2 cells. These results indicate that many Arcobacter species are potential pathogens of humans and animals.

  4. The advantage of mucus for adhesive locomotion in gastropods.

    Science.gov (United States)

    Iwamoto, Mayuko; Ueyama, Daishin; Kobayashi, Ryo

    2014-07-21

    For many gastropods, locomotion is driven by a succession of periodic muscular waves (contractions and relaxations) moving along the foot. The force generated by these waves is coupled to the substratum by a thin layer of pedal mucus. Gastropod pedal mucus has unusual physical properties: the mucus is a viscoelastic solid at small deformation and shows a sharp yield point; then, at greater strains, the mucus is a viscous liquid, although it will recover its solidity if allowed to heal for a certain period. In this paper, to clarify the role of the mucus and the flexible muscular waves in adhesive locomotion, we use a simple mathematical model to verify that directional migration can be realized through the interaction between the periodic muscular waves and the specific physical features of mucus. Our results indicate that the hysteresis property of mucus is essential in controlling kinetic friction for the realization of crawling locomotion. Furthermore, our numerical calculations show that both the hysteresis property of mucus and the contraction ratio of muscle give rise to two styles of locomotion, direct waves and retrograde waves, which until now have been explained by different mechanisms. The biomechanical effectiveness of mucus in adhesive locomotion is also discussed.

  5. Aerosol Medications for Treatment of Mucus Clearance Disorders.

    Science.gov (United States)

    Rubin, Bruce K

    2015-06-01

    Airway mucus hypersecretion and secretion retention can result from inflammation, irritation, stimulation, or mucus-producing tumors. Secretion clearance can be furthered hampered by ciliary dysfunction and by weakness or restrictive lung disease, leading to an ineffective cough. There are a number of different mucoactive medications that have been used to reduce hypersecretion, make secretions easier to transport, or increase the efficiency of cough or mucus clearance. In this paper, I review the pathophysiology of secretory hyper-responsiveness and mucus hypersecretion and discuss the different aerosol medications that can be used to augment secretion clearance. Copyright © 2015 by Daedalus Enterprises.

  6. Total Body Irradiation in the "Hematopoietic" Dose Range Induces Substantial Intestinal Injury in Non-Human Primates.

    Science.gov (United States)

    Wang, Junru; Shao, Lijian; Hendrickson, Howard P; Liu, Liya; Chang, Jianhui; Luo, Yi; Seng, John; Pouliot, Mylene; Authier, Simon; Zhou, Daohong; Allaben, William; Hauer-Jensen, Martin

    2015-11-01

    The non-human primate has been a useful model for studies of human acute radiation syndrome (ARS). However, to date structural changes in various parts of the intestine after total body irradiation (TBI) have not been systematically studied in this model. Here we report on our current study of TBI-induced intestinal structural injury in the non-human primate after doses typically associated with hematopoietic ARS. Twenty-four non-human primates were divided into three groups: sham-irradiated control group; and total body cobalt-60 (60Co) 6.7 Gy gamma-irradiated group; and total body 60Co 7.4 Gy gamma-irradiated group. After animals were euthanized at day 4, 7 and 12 postirradiation, sections of small intestine (duodenum, proximal jejunum, distal jejunum and ileum) were collected and fixed in 10% formalin. The intestinal mucosal surface length, villus height and crypt depths were assessed by computer-assisted image analysis. Plasma citrulline levels were determined using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Total bone marrow cells were counted and hematopoietic stem/progenitor cells in bone marrow were analyzed by flow cytometer. Histopathologically, all segments exhibited conspicuous disappearance of plicae circulares and prominent atrophy of crypts and villi. Intestinal mucosal surface length was significantly decreased in all intestinal segments on day 4, 7 and 12 after irradiation (P 0.05). Crypt depth was also significantly reduced in all segments on day 4, 7 and 12 after irradiation (P irradiation, consistent with intestinal mucosal injury. Both 6.7 and 7.4 Gy TBI reduced total number of bone marrow cells. And further analysis showed that the number and function of CD45(+)CD34(+) hematopoietic stem/progenitors in bone marrow decreased significantly. In summary, TBI in the hematopoietic ARS dose range induces substantial intestinal injury in all segments of the small bowel. These findings underscore the importance of maintaining the

  7. Rapid reversal of human intestinal ischemia-reperfusion induced damage by shedding of injured enterocytes and reepithelialisation.

    Directory of Open Access Journals (Sweden)

    Joep P M Derikx

    Full Text Available BACKGROUND: Intestinal ischemia-reperfusion (IR is a phenomenon related to physiological conditions (e.g. exercise, stress and to pathophysiological events (e.g. acute mesenteric ischemia, aortic surgery. Although intestinal IR has been studied extensively in animals, results remain inconclusive and data on human intestinal IR are scarce. Therefore, an experimental harmless model for human intestinal IR was developed, enabling us to clarify the sequelae of human intestinal IR for the first time. METHODS AND FINDINGS: In 30 patients undergoing pancreatico-duodenectomy we took advantage of the fact that in this procedure a variable length of jejunum is removed. Isolated jejunum (5 cm was subjected to 30 minutes ischemia followed by reperfusion. Intestinal Fatty Acid Binding Protein (I-FABP arteriovenous concentration differences across the bowel segment were measured before and after ischemia to assess epithelial cell damage. Tissue sections were collected after ischemia and at 25, 60 and 120 minutes reperfusion and stained with H&E, and for I-FABP and the apoptosis marker M30. Bonferroni's test was used to compare I-FABP differences. Mean (SEM arteriovenous concentration gradients of I-FABP across the jejunum revealed rapidly developing epithelial cell damage. I-FABP release significantly increased from 290 (46 pg/ml before ischemia towards 3,997 (554 pg/ml immediately after ischemia (p<0.001 and declined gradually to 1,143 (237 pg/ml within 1 hour reperfusion (p<0.001. Directly after ischemia the intestinal epithelial lining was microscopically normal, while subepithelial spaces appeared at the villus tip. However, after 25 minutes reperfusion, enterocyte M30 immunostaining was observed at the villus tip accompanied by shedding of mature enterocytes into the lumen and loss of I-FABP staining. Interestingly, within 60 minutes reperfusion the epithelial barrier resealed, while debris of apoptotic, shedded epithelial cells was observed in the lumen

  8. Expression of acyl-CoA synthetase 5 reflects the state of villus architecture in human small intestine

    DEFF Research Database (Denmark)

    Gassler, Nikolaus; Kopitz, Jürgen; Tehrani, Arman

    2004-01-01

    . Screening of antibodies from a hybridoma library led to the identification of an acyl-CoA synthetase 5-specific monoclonal antibody. Protein synthesis, mRNA expression, and the enzyme activity of acyl-CoA synthetase 5 were studied by several methods in human small intestinal tissues with Crohn's disease...... or coeliac disease, respectively. Acyl-CoA synthetase 5 mRNA and protein levels were substantially reduced in injured small intestinal mucosa. Moreover, impaired synthesis of the acyl-CoA synthetase 5 protein was reflected by a decrease in intramucosal enzyme activity. Subtle changes of the acyl...

  9. Analysis of the human intestinal epithelial cell transcriptional response to Lactobacillus acidophilus, Lactobacillus salivarius, Bifidobacterium lactis and Escherichia coli

    DEFF Research Database (Denmark)

    Putaala, H; Barrangou, R; Leyer, G J

    2010-01-01

    The complex microbial population residing in the human gastrointestinal tract consists of commensal, potential pathogenic and beneficial species, which are probably perceived differently by the host and consequently could be expected to trigger specific transcriptional responses. Here, we provide...... insights into the relationship between probiotics and human intestinal epithelial cells, notably with regard to strain-specific responses, and highlight the differences between transcriptional responses to pathogenic and probiotic bacteria.......The complex microbial population residing in the human gastrointestinal tract consists of commensal, potential pathogenic and beneficial species, which are probably perceived differently by the host and consequently could be expected to trigger specific transcriptional responses. Here, we provide...... a comparative analysis of the global in vitro transcriptional response of human intestinal epithelial cells to Lactobacillus acidophilus NCFM™, Lactobacillus salivarius Ls-33, Bifidobacterium animalis subsp. lactis 420, and enterohaemorrhagic Escherichia coli O157:H7 (EHEC). Interestingly, L. salivarius Ls-33...

  10. Biotransformation of 1-nitropyrene to 1-aminopyrene and N-formyl-1-aminopyrene by the human intestinal microbiota

    Energy Technology Data Exchange (ETDEWEB)

    Manning, B.W.; Cerniglia, C.E.; Federle, T.W.

    1986-01-01

    The nitropolycyclic aromatic hydrocarbon 1-nitropyrene (1-NP) is an environmental pollutant, a potent bacterial and mammalian mutagen, and a carcinogen. The metabolism of 1-NP by the human intestinal microbiota was studied using a semicontinuous culture system that simulates the colonic lumen. (/sup 3/H)-1-Nitropyrene was metabolized by the intestinal microbiota to 1-aminopyrene (1-AP) and N-formyl-1-aminopyrene (FAP) as determined by high-performance liquid chromatography (HPLC) and mass spectrometry. Twenty-four hours after the addition of (/sup 3/H)-1-NP, the formylated compound and 1-AP accounted for 20 and 80% of the total metabolism respectively. This percentage increased to 66% for FAP after 24 h following 10 d of chronic exposure to unlabeled 1-NP, suggesting metabolic adaptation to 1-NP by the microbiota. Both 1-AP and FAP have been shown to be nonmutagenic towards Salmonella typhimurium TA98, which indicates that the intestinal microflora may potentially detoxify 1-NP.

  11. Effect of intravenous infusion of glyceryl trinitrate on gastric and small intestinal motor function in healthy humans

    DEFF Research Database (Denmark)

    Madsen, Jan Lysgård; Fuglsang, Stefan; Graff, J

    2006-01-01

    : To examine the effect of intravenous infusion of glyceryl trinitrate on gastric and small intestinal motor function after a meal in healthy humans. METHODS: Nine healthy volunteers participated in a placebo-controlled, double-blind, crossover study. Each volunteer was examined during intravenous infusion...... of glyceryl trinitrate 1 microg/kg x min or saline. A gamma camera technique was used to measure gastric emptying and small intestinal transit after a 1600-kJ mixed liquid and solid meal. Furthermore, duodenal motility was assessed by manometry. RESULTS: Glyceryl trinitrate did not change gastric mean...... emptying time, gastric half emptying time, gastric retention at 15 min or small intestinal mean transit time. Glyceryl trinitrate did not influence the frequency of duodenal contractions, the amplitude of duodenal contractions or the duodenal motility index. CONCLUSIONS: Intravenous infusion of glyceryl...

  12. Pharmacologic agents for mucus clearance in bronchiectasis.

    Science.gov (United States)

    Nair, Girish B; Ilowite, Jonathan S

    2012-06-01

    There are no approved pharmacologic agents to enhance mucus clearance in non-cystic fibrosis (CF) bronchiectasis. Evidence supports the use of hyperosmolar agents in CF, and studies with inhaled mannitol and hypertonic saline are ongoing in bronchiectasis. N-acetylcysteine may act more as an antioxidant than a mucolytic in other lung diseases. Dornase α is beneficial to patients with CF, but is not useful in patients with non-CF bronchiectasis. Mucokinetic agents such as β-agonists have the potential to improve mucociliary clearance in normals and many disease states, but have not been adequately studied in patients with bronchiectasis.

  13. Structural features of colloidal species in the human fasted upper small intestine

    DEFF Research Database (Denmark)

    Mullertz, Anette; Reppas, Christos; Psachoulias, Dimitrios;

    2015-01-01

    Objectives This paper aims to study the features of colloidal species in the lumen of the upper small intestine of two healthy adults at fasted state by means of electron microscopy. Methods Samples were aspirated from a location near the ligament of Treitz 30 min (volunteer no. 1, Aspirate30min...... with previously studied samples from the lower intestine in the fasted state. Micelles and unilamellar vesicles observed in both samples closely resemble morphological characteristics of those found in fluids simulating the colloidal species in fasted upper intestinal environment. Conclusions Features...... of colloidal species in contents of fasted small intestine have similarities with fluids simulating the contents in fasted upper small intestine and with contents of lower intestine in the fasted state....

  14. EP receptor expression in human intestinal epithelium and localization relative to the stem cell zone of the crypts.

    Science.gov (United States)

    Olsen Hult, Lene Th; Kleiveland, Charlotte R; Fosnes, Kjetil; Jacobsen, Morten; Lea, Tor

    2011-01-01

    There is substantial evidence for PGE2 affecting intestinal epithelial proliferation. PGE2 is also reported to be involved in the regulation of growth and differentiation in adult stem cells, both effects mediated by binding to EP-receptors. We have used the Lgr5 as a marker to scrutinize EP-receptor and COX expression in human intestinal epithelial cells with focus on the stem cell area of the crypts. Normal tissue from ileum and colon, but also duodenal biopsies from patients with untreated celiac disease, were investigated by immunohistochemistry and RT-PCR. The combination of fresh flash-frozen tissue and laser microdissection made it possible to isolate RNA from the epithelial cell layer, only. In the small intestine, Lgr5 labels cells are in the +4 position, while in the colon, Lgr5 positive cells are localized to the crypt bottoms. Epithelial crypt cells of normal small intestine expressed neither EP-receptor mRNA nor COX1/2. However, crypt cells in tissue from patients with untreated celiac disease expressed EP2/4 receptor and COX1 mRNA. In the colon, the situation was different. Epithelial crypt cells from normal colon were found to express EP2/4 receptor and COX1/2 transcripts. Thus, there are distinct differences between normal human small intestine and colon with regard to expression of EP2/4 receptors and COX1/2. In normal colon tissue, PGE2-mediated signaling through EP-receptors 2/4 could be involved in regulation of growth and differentiation of the epithelium, while the lack of EP-receptor expression in the small intestinal tissue exclude the possibility of a direct effect of PGE2 on the crypt epithelial cells.

  15. EP receptor expression in human intestinal epithelium and localization relative to the stem cell zone of the crypts.

    Directory of Open Access Journals (Sweden)

    Lene Th Olsen Hult

    Full Text Available There is substantial evidence for PGE2 affecting intestinal epithelial proliferation. PGE2 is also reported to be involved in the regulation of growth and differentiation in adult stem cells, both effects mediated by binding to EP-receptors. We have used the Lgr5 as a marker to scrutinize EP-receptor and COX expression in human intestinal epithelial cells with focus on the stem cell area of the crypts. Normal tissue from ileum and colon, but also duodenal biopsies from patients with untreated celiac disease, were investigated by immunohistochemistry and RT-PCR. The combination of fresh flash-frozen tissue and laser microdissection made it possible to isolate RNA from the epithelial cell layer, only. In the small intestine, Lgr5 labels cells are in the +4 position, while in the colon, Lgr5 positive cells are localized to the crypt bottoms. Epithelial crypt cells of normal small intestine expressed neither EP-receptor mRNA nor COX1/2. However, crypt cells in tissue from patients with untreated celiac disease expressed EP2/4 receptor and COX1 mRNA. In the colon, the situation was different. Epithelial crypt cells from normal colon were found to express EP2/4 receptor and COX1/2 transcripts. Thus, there are distinct differences between normal human small intestine and colon with regard to expression of EP2/4 receptors and COX1/2. In normal colon tissue, PGE2-mediated signaling through EP-receptors 2/4 could be involved in regulation of growth and differentiation of the epithelium, while the lack of EP-receptor expression in the small intestinal tissue exclude the possibility of a direct effect of PGE2 on the crypt epithelial cells.

  16. Two-dimensional gel proteome reference map of human small intestine

    Directory of Open Access Journals (Sweden)

    Canzonieri Vincenzo

    2009-03-01

    Full Text Available Abstract Background The small intestine is an important human organ that plays a central role in many physiological functions including digestion, absorption, secretion and defense. Duodenal pathologies include, for instance, the ulcer associated to Helicobacter Pylori infection, adenoma and, in genetically predisposed individuals, celiac disease. Alterations in the bowel reduce its capability to absorb nutrients, minerals and fat-soluble vitamins. Anemia and osteopenia or osteoporosis may develop as a consequence of vitamins malabsorption. Adenoma is a benign tumor that has the potential to become cancerous. Adult celiac disease patients present an overall risk of cancer that is almost twice than that found in the general population. These disease processes are not completely known. To date, a two dimensional (2D reference map of proteins expressed in human duodenal tissue is not yet available: the aim of our study was to characterize the 2D protein map, and to identify proteins of duodenal mucosa of adult individuals without duodenal illness, to create a protein database. This approach, may be useful for comparing similar protein samples in different laboratories and for the molecular characterization of intestinal pathologies without recurring to the use of surgical material. Results The enrolled population comprised five selected samples (3 males and 2 females, aged 19 to 42, taken from 20 adult subjects, on their first visit at the gastroenterology unit for a suspected celiac disease, who did not turn to be affected by any duodenal pathology after gastrointestinal and histological evaluations. Proteins extracted from the five duodenal mucosal specimens were singly separated by 2D gel electrophoresis. After image analysis of each 2D gel, 179 protein spots, representing 145 unique proteins, from 218 spots tested, were successfully identified by MALDI-TOF ms analysis. Normalized volumes, for each protein, have been reported for every gel

  17. Isolation of Human Intestinal Bacteria Capable of Producing the Bioactive Metabolite Isourolithin A from Ellagic Acid

    Directory of Open Access Journals (Sweden)

    María V. Selma

    2017-08-01

    Full Text Available Urolithins are intestinal microbial metabolites produced from ellagitannin- and ellagic acid-containing foods such as walnuts, strawberries, and pomegranates. These metabolites, better absorbed than their precursors, can contribute significantly to the beneficial properties attributed to the polyphenols ellagitannins and ellagic acid (EA. However, both the ability of producing the final metabolites in this catabolism (urolithins A, B and isourolithin A and the health benefits associated with ellagitannin consumption differ considerably among individuals depending on their gut microbiota composition. Three human urolithin metabotypes have been previously described, i.e., metabotype 0 (urolithin non-producers, metabotype A (production of urolithin A as unique final urolithin and metabotype B (urolithin B and/or isourolithin A are produced besides urolithin A. Although production of some intermediary urolithins has been recently attributed to intestinal species from Eggerthellaceae family named Gordonibacter urolithinfaciens and Gordonibacter pamelaeae, the identification of the microorganisms responsible for the complete transformation of EA into the final urolithins, especially those related to metabotype B, are still unknown. In the present research we illustrate the isolation of urolithin-producing strains from human feces of a healthy adult and their ability to transform EA into different urolithin metabolites, including isourolithin A. The isolates belong to a new genus from Eggerthellaceae family. EA transformation and urolithin production arisen during the stationary phase of the growth of the bacteria under anaerobic conditions. The HPLC-DAD-MS analyses demonstrated the sequential appearance of 3,8,9,10-tetrahydroxy-urolithin (urolithin M6, 3,8,9-trihydroxy-urolithin (urolithin C and 3,9-dihydroxy-urolithin (isourolithin A while 3,8-dihydroxy-urolithin (urolithin A and 3-hydroxy-urolithin (urolithin B were not detected. For the first time

  18. Studies on the bioavailability of zinc in humans: intestinal interaction of tin and zinc.

    Science.gov (United States)

    Solomons, N W; Marchini, J S; Duarte-Favaro, R M; Vannuchi, H; Dutra de Oliveira, J E

    1983-04-01

    Mineral/mineral interactions at the intestinal level are important in animal nutrition and toxicology, but only limited understanding of their extent or importance in humans has been developed. An inhibitory interaction of dietary tin on zinc retention has been recently described from human metabolic studies. We have explored the tin/zinc interaction using the change-in-plasma-zinc-concentration method with a standard dosage of 12.5 mg of zinc as zinc sulfate in 100 ml of Coca-Cola. Sn/Zn ratios of 2:1, 4:1, and 8:1, constituted by addition of 25, 50, and 100 mg of tin as stannous chloride, had no significant overall effect on zinc uptake. The 100-mg dose of tin produced noxious gastrointestinal symptoms. Addition of iron as ferrous sulfate to form ratios of Sn/Fe/Zn of 1:1:1 and 2:2:1 with the standard zinc solution and the appropriate doses of tin produced a reduction of zinc absorption not dissimilar from that seen previously with zinc and iron alone, and addition of picolinic acid did not influence the uptake of zinc from the solution with the 2:2:1 Sn/Fe/Zn ratio.

  19. Using human intestinal biopsies to study the pathogenesis of irritable bowel syndrome.

    Science.gov (United States)

    Nasser, Y; Boeckxstaens, G E; Wouters, M M; Schemann, M; Vanner, S

    2014-04-01

    Although animal models of the irritable bowel syndrome (IBS) have provided important insights, there are no models that fully express the features of this complex condition. One alternative approach is the use of human intestinal biopsies obtained during endoscopic procedures to examine peripheral mechanisms in this disorder. These studies have served to confirm the existence of peripheral pathways in humans with IBS and have provided many new mechanistic insights. Two general approaches have been employed; one approach has been to examine the biological activity of mediators within the mucosal tissue of IBS patients and the other has been to examine changes in the structural properties of key signaling pathways contained within the biopsies. Using these approaches, important changes have been discovered involving the enteric nervous system and the extrinsic sensory pathway (dorsal root ganglia neurons), the immune system, and epithelial signaling in IBS patients compared to healthy subjects. This review will systematically explore these mechanistic pathways, highlight the implications of these novel findings and discuss some of the important limitations of this approach. © 2014 John Wiley & Sons Ltd.

  20. Soluble Human Intestinal Lactoferrin Receptor: Ca(2+)-Dependent Binding to Sepharose-Based Matrices.

    Science.gov (United States)

    Oshima, Yuta; Seki, Kohei; Shibuya, Masataka; Naka, Yuki; Yokoyama, Tatsuya; Sato, Atsushi

    2016-01-01

    A soluble form of human intestinal lactoferrin receptor (shLFR) is identical to human intelectin-1 (hITLN-1), a galactofuranose-binding protein that acts as a host defense against invading pathogenic microorganisms. We found that recombinant shLFR, expressed in mammalian cells (CHO DG44, COS-1, and RK13), binds tightly to Sepharose 4 Fast Flow (FF)-based matrices in a Ca(2+)-dependent manner. This binding of shLFR to Sepharose 4 FF-based matrices was inhibited by excess D-galactose, but not by D-glucose, suggesting that shLFR recognizes repeating units of α-1,6-linked D-galactose in Sepharose 4 FF. Furthermore, shLFR could bind to both Sepharose 4B- and Sepharose 6B-based matrices that were not crosslinked in a similar manner as to Sepharose 4 FF-based matrices. Therefore, shLFR (hITLN-1) binds to Sepharose-based matrices in a Ca(2+)-dependent manner. This binding property is most likely related to the ability, as host defense lectins, to recognize sepharose (agarobiose)-like structures present on the surface of invading pathogenic microorganisms.

  1. An immunohistochemical study and review of potential markers of human intestinal M cells

    Directory of Open Access Journals (Sweden)

    NACS Wong

    2009-06-01

    Full Text Available M cells are found in intestinal follicle associated epithelium. Studies into the physiological and pathological roles of human M cells have been hampered by the lack of well-substantiated, specific markers for these cells. A critical literature review suggests the following molecules may potentially serve as such markers: CK7, FcaR (CD89, S100, CD1a, CD21, CD23, sialyl Lewis A, and cathepsin E. Normal ileum, appendix and colorectum were studied using paraffinembedded, formalin-fixed tissue and immunohistochemistry for these 8 markers. Cathepsin E immunohistochemistry was also performed on cases of colorectal adenocarcinoma, colorectal adenoma, colorectal hyperplastic/metaplastic polyp, lymphocytic colitis, collagenous colitis, pseudomembranous colitis and active ulcerative colitis. Of the 8 markers tested, only cathepsin E appeared to be specific to follicle associated epithelium (expressed by cells with and without M cell morphology and follicular crypt epithelium; this specificity was limited to the colorectum. Focal epithelial expression of cathepsin E was seen in adenocarcinoma, adenoma, hyperplastic/metaplastic polyp, ulcerative colitis and pseudomembranous colitis. In conclusion, cathepsin E is a specific marker of normal colorectal follicle associated epithelium and follicular crypt epithelium though is not specific to M cells within these compartments. None of the other 7 markers studied is exclusively expressed by human M cells.

  2. Molecular paleoparasitological hybridization approach as effective tool for diagnosing human intestinal parasites from scarce archaeological remains.

    Science.gov (United States)

    Jaeger, Lauren Hubert; Iñiguez, Alena Mayo

    2014-01-01

    Paleoparasitology is the science that uses parasitological techniques for diagnosing parasitic diseases in the past. Advances in molecular biology brought new insights into this field allowing the study of archaeological material. However, due to technical limitations a proper diagnosis and confirmation of the presence of parasites is not always possible, especially in scarce and degraded archaeological remains. In this study, we developed a Molecular Paleoparasitological Hybridization (MPH) approach using ancient DNA (aDNA) hybridization to confirm and complement paleoparasitological diagnosis. Eight molecular targets from four helminth parasites were included: Ascaris sp., Trichuris trichiura, Enterobius vermicularis, and Strongyloides stercoralis. The MPH analysis using 18th century human remains from Praça XV cemetery (CPXV), Rio de Janeiro, Brazil, revealed for the first time the presence E. vermicularis aDNA (50%) in archaeological sites of Brazil. Besides, the results confirmed T. trichiura and Ascaris sp. infections. The prevalence of infection by Ascaris sp. and E. vermicularis increased considerably when MPH was applied. However, a lower aDNA detection of T. trichiura (40%) was observed when compared to the diagnosis by paleoparasitological analysis (70%). Therefore, based on these data, we suggest a combination of Paleoparasitological and MPH approaches to verify the real panorama of intestinal parasite infection in human archeological samples.

  3. Why do humans have two glucocorticoids: A question of intestinal fortitude.

    Science.gov (United States)

    Morris, David J

    2015-10-01

    The main purpose of this review article is threefold (a) to try to address the question "why are two adrenal glucocorticoids, cortisol and corticosterone, secreted by humans and other mammalian species?", (b) to outline a hypothesis that under certain physiological conditions, corticosterone has additional biochemical functions over and above those of cortisol, and (c) to emphasize the role of gastrointestinal bacteria in chemically transforming corticosterone into metabolites and that these re-cycled metabolites can be reabsorbed from the enterohepatic circuit. Cortisol and its metabolites are not secreted into the bile and thus are excluded from the enterohepatic circuit. Corticosterone was the first steroid hormone isolated from adrenal gland extracts. Many believe that corticosterone functions identically to cortisol. Yet, corticosterone causes significant sodium retention and potassium secretion in Addisonian patients, unlike cortisol. In humans, corticosterone and its metabolite, 3α,5α-TH-corticosterone, are excreted via the bile in humans where they are transformed in the intestine by anaerobic bacteria into 21-dehydroxylated products: 11β-OH-progesterone or 11β-OH-(allo)-5α-preganolones. These metabolites inhibit 11β-HSD2 and 11β-HSD1 dehydrogenase, being many-fold more potent than 3α,5α-TH-cortisol. Corticosterone has significantly lower Km's for both 11β-HSD2 and 11β-HSD1 enzymatic dehydrogenase activity, compared to cortisol. Patients diagnosed with 17α-hydroxylase deficiency have elevated blood pressure and high levels of circulating corticosterone, 3α,5α-TH-corticosterone, and their 21-dehydroxlated corticosterone derivatives. In humans, these 5α-corticosterone metabolites are likely to influence blood pressure regulation and Na(+) retention by inhibiting the rate of deactivation of cortisol by 11β-HSD isoforms.

  4. Challenges of culturing human norovirus in three-dimensional organoid intestinal cell culture models.

    Directory of Open Access Journals (Sweden)

    Efstathia Papafragkou

    Full Text Available Human noroviruses are the most common cause of acute gastroenteritis worldwide. Recently, cell culture systems have been described using either human embryonic intestinal epithelial cells (Int-407 or human epithelial colorectal adenocarcinoma cells (Caco-2 growing on collagen-I porous micro carrier beads in a rotating bioreactor under conditions of physiological fluid shear. Here, we describe the efforts from two independent laboratories to implement this three dimensional (3D cell culture system for the replication of norovirus. Int-407 and Caco-2 were grown in a rotating bioreactor for up to 28 days. Prior to infection, cells were screened for the presence of microvilli by electron microscopy and stained for junction proteins (zonula occludens-1, claudin-1, and β-catenin. Differentiated 3D cells were transferred to 24-well plates and infected with bacteria-free filtrates of various norovirus genotypes (GI.1, GI.3, GI.8, GII.2, GII.4, GII.7, and GII.8. At 12 h, 24 h, and 48 h post inoculation, viral RNA from both cells and supernatants were collected and analyzed for norovirus RNA by real-time reverse transcription PCR. Despite observations of high expression of junction proteins and microvilli development in stained thin sections, our data suggest no significant increase in viral titer based on norovirus RNA copy number during the first 48 h after inoculation for the different samples and virus culture conditions tested. Our combined efforts demonstrate that 3D cell culture models using Int-407 or Caco-2 cells do not support norovirus replication and highlight the complexity and difficulty of developing a reproducible in vitro cell culture system for human norovirus.

  5. Rapid reversal of human intestinal ischemia-reperfusion induced damage by shedding of injured enterocytes and reepithelialisation.

    Science.gov (United States)

    Derikx, Joep P M; Matthijsen, Robert A; de Bruïne, Adriaan P; van Bijnen, Annemarie A; Heineman, Erik; van Dam, Ronald M; Dejong, Cornelis H C; Buurman, Wim A

    2008-01-01

    Intestinal ischemia-reperfusion (IR) is a phenomenon related to physiological conditions (e.g. exercise, stress) and to pathophysiological events (e.g. acute mesenteric ischemia, aortic surgery). Although intestinal IR has been studied extensively in animals, results remain inconclusive and data on human intestinal IR are scarce. Therefore, an experimental harmless model for human intestinal IR was developed, enabling us to clarify the sequelae of human intestinal IR for the first time. In 30 patients undergoing pancreatico-duodenectomy we took advantage of the fact that in this procedure a variable length of jejunum is removed. Isolated jejunum (5 cm) was subjected to 30 minutes ischemia followed by reperfusion. Intestinal Fatty Acid Binding Protein (I-FABP) arteriovenous concentration differences across the bowel segment were measured before and after ischemia to assess epithelial cell damage. Tissue sections were collected after ischemia and at 25, 60 and 120 minutes reperfusion and stained with H&E, and for I-FABP and the apoptosis marker M30. Bonferroni's test was used to compare I-FABP differences. Mean (SEM) arteriovenous concentration gradients of I-FABP across the jejunum revealed rapidly developing epithelial cell damage. I-FABP release significantly increased from 290 (46) pg/ml before ischemia towards 3,997 (554) pg/ml immediately after ischemia (pintestinal epithelial lining was microscopically normal, while subepithelial spaces appeared at the villus tip. However, after 25 minutes reperfusion, enterocyte M30 immunostaining was observed at the villus tip accompanied by shedding of mature enterocytes into the lumen and loss of I-FABP staining. Interestingly, within 60 minutes reperfusion the epithelial barrier resealed, while debris of apoptotic, shedded epithelial cells was observed in the lumen. At the same time, M30 immunoreactivity was absent in intact epithelial lining. This is the first human study to clarify intestinal IR induced cell damage and

  6. Optical properties of human normal small intestine tissue determined by Kubelka-Munk method in vitro

    Institute of Scientific and Technical Information of China (English)

    Hua-Jiang Wei; Da Xing; Guo-Yong Wu; Ying Jin; Huai-Min Gu

    2003-01-01

    AIM: To study the optical properties of human normal small intestine tissue at 476.5 nm, 488 nm, 496.5 nm, 514.5 nm,532 nm, 808 nm wavelengths of laser irradiation.METHODS: A double-integrating-sphere system, the basic principle of measuring technology of light radiation, and an optical model of biological tissues were used in the study.RESULTS: The results of measurement showed that there were no significant differences in the absorption coefficients of human normal small intestine tissue at 476.5 nm, 488 nm,496.5 nm laser in the Kubelka-Munk two-flux model (P>0.05).The absorption coefficients of the tissue at 514.5 nm, 532 nm,808 nm laser irradiation were obviously increased with the decrease of these wavelengths. The scattering coefficients of the tissue at 476.5 nm, 488 nm, 496.5 nm laser irradiation were increased with the decrease of these wavelengths.The scattering coefficients at 496.5 nm, 514.5 nm, 532 nm laser irradiation were obviously increased with the increase of these wavelengths. The scattering coefficient of the tissue at 532 nm laser irradiation was bigger than that at 808 nm.There were no significant differences in the total attenuation coefficient of the tissue at 476.5 nm and 488 nm laser irradiation (P>0.05). The total attenuation coefficient of the tissue at 488 nm, 496.5 nm, 514.5 nm, 532 nm, 808 nm laser irradiation was obviously increased with the decrease of these wavelengths, and their effective attenuation coefficient revealed the same trend. There were no significant differences among the forward scattered photon fluxe,backward scattered photon fiuxe, and total scattered photon fiuxe of the tissue at 476.5 nm, 488 nm, 496.5 nm laser irradiation. They were all obviously increased with attenuation of tissue thickness. The attenuations of forward and backward scattered photon fluxes, and the total scattered photon fiuxe of the tissue at 514.5 nm laser irradiation were slower than those at 476.5 nm, 488 nm, 496.5 nm laser irradiation

  7. Dipeptide model prodrugs for the intestinal oligopeptide transporter. Affinity for and transport via hPepT1 in the human intestinal Caco-2 cell line

    DEFF Research Database (Denmark)

    Nielsen, C U; Andersen, R; Brodin, Birger

    2001-01-01

    The human intestinal di/tri-peptide carrier, hPepT1, has been suggested as a drug delivery target via increasing the intestinal transport of low permeability compounds by designing peptidomimetic prodrugs. Model ester prodrugs using the stabilized dipeptides D-Glu-Ala and D-Asp-Ala as pro......-moieties for benzyl alcohol have been shown to maintain affinity for hPepT1. The primary aim of the present study was to investigate if modifications of the benzyl alcohol model drug influence the corresponding D-Glu-Ala and D-Asp-Ala model prodrugs' affinity for hPepT1 in Caco-2 cells. A second aim...... was to investigate the transepithelial transport and hydrolysis parameters for D-Asp(BnO)-Ala and D-Glu(BnO)-Ala across Caco-2 cell monolayers. In the present study, all investigated D-Asp-Ala and D-Glu-Ala model prodrugs retained various degrees of affinity for hPepT1 in Caco-2 cells. These affinities are used...

  8. Core 1- and 3-derived O-glycans collectively maintain the colonic mucus barrier and protect against spontaneous colitis in mice.

    OpenAIRE

    Bergstrom, K; Fu,J.; Johansson, MEV; Liu, X; Gao, N; Q. Wu; J. Song; McDaniel, JM; McGee, S; Chen, W.; Braun, J; Hansson, GC; Xia, L

    2016-01-01

    Core 1- and 3-derived mucin-type O-glycans are primary components of the mucus layer in the colon. Reduced mucus thickness and impaired O-glycosylation are observed in human ulcerative colitis. However, how both types of O-glycans maintain mucus barrier function in the colon is unclear. We found that C1galt1 expression, which synthesizes core 1 O-glycans, was detected throughout the colon, whereas C3GnT, which controls core 3 O-glycan formation, was most highly expressed in the proximal colon...

  9. Core 1- and core 3-derived O-glycans collectively maintain the colonic mucus barrier and protect against spontaneous colitis in mice

    OpenAIRE

    Bergstrom, Kirk; Fu, Jianxin; Johansson, Malin EV; Liu, Xiaowei; Gao, Nan; Wu,Qian; Song, Jianhua; McDaniel, J. Michael; McGee, Samuel; Chen, Weichang; Braun, Jonathan; Hansson, Gunnar C; Xia, Lijun

    2016-01-01

    Core 1- and core 3-derived mucin-type O-glycans are primary components of the mucus layer in the colon. Reduced mucus thickness and impaired O-glycosylation are observed in human ulcerative colitis. However, how both types of O-glycans maintain mucus barrier function in the colon is unclear. We found that C1galt1 expression, which synthesizes core 1 O-glycans, was detected throughout the colon, whereas C3GnT, which controls core 3 O-glycan formation, was most highly expressed in the proximal ...

  10. Crystallization of Bovine Cervical Mucus at Oestrus: An Update

    Directory of Open Access Journals (Sweden)

    Manuel E. Cortés

    2014-07-01

    Full Text Available Bovine cervical mucus changes its biochemical composition and biophysical properties due to the variations in sex steroid levels during the oestrous cycle. As a consequence of oestrogen rise, cervical mucus is produced in larger amounts at oestrus—a stage also characterized by an increase in mucus crystallization when observed under light microscopy. The objective of this article is to provide an updated review of the main aspects regarding crystallization of bovine cervical mucus. First, it makes reference to the composition of cervical mucus and the critical functions that this secretion exerts on bovine reproductive physiology, as well as in other species. Then, the article deals with the phenomenon of crystallization observed in cervical mucus, describing the main models used to classify the crystalline patterns observable in mucus at oestrus stage (some of them resembling ferns, palm leaves and stellar patterns, among others. Finally, it addresses the importance of the phenomenon of cervical mucus crystallization for the understanding of bovine reproductive physiology.

  11. Contribution of the Intestinal Microbiota to Human Health: From Birth to 100 Years of Age

    NARCIS (Netherlands)

    Cheng, J.; Palva, A.M.; Vos, de W.M.; Satokari, R.

    2013-01-01

    Our intestinal tract is colonized since birth by multiple microbial species that show a characteristic succession in time. Notably the establishment of the microbiota in early life is important as it appears to impact later health. While apparently stable in healthy adults, the intestinal microbiota

  12. Faecal mucus degrading glycosidases in ulcerative colitis and Crohn's disease.

    Science.gov (United States)

    Rhodes, J M; Gallimore, R; Elias, E; Allan, R N; Kennedy, J F

    1985-08-01

    Because the normal faecal flora includes bacteria which can produce mucus-digesting glycosidases, it follows that increased digestion of colonic mucus by these bacterial enzymes could be important in the pathogenesis of ulcerative colitis. Faecal activities of potential mucus-degrading glycosidases have therefore been assayed in samples from patients with inflammatory bowel disease and normal controls. The enzymes alpha-D-galactosidase, beta-D-galactosidase, beta-NAc-D-glucosaminidase alpha-L-fucosidase and neuraminidase were assayed. Considerable glycosidase activity was present in most faecal samples. Similar activities of all the enzymes assayed were found in faeces from patients with ulcerative colitis, Crohn's disease and normal controls and there was no significant correlation with disease activity. These results imply that relapse of ulcerative colitis is not initiated by increased degradation of colonic mucus by faecal glycosidases but do not exclude a role for bacterial mucus degradation in the pathogenesis of ulcerative colitis.

  13. Determination of tolerable fatty acids and cholera toxin concentrations using human intestinal epithelial cells and BALB/c mouse macrophages.

    Science.gov (United States)

    Tamari, Farshad; Tychowski, Joanna; Lorentzen, Laura

    2013-05-30

    The positive role of fatty acids in the prevention and alleviation of non-human and human diseases have been and continue to be extensively documented. These roles include influences on infectious and non-infectious diseases including prevention of inflammation as well as mucosal immunity to infectious diseases. Cholera is an acute intestinal illness caused by the bacterium Vibrio cholerae. It occurs in developing nations and if left untreated, can result in death. While vaccines for cholera exist, they are not always effective and other preventative methods are needed. We set out to determine tolerable concentrations of three fatty acids (oleic, linoleic and linolenic acids) and cholera toxin using mouse BALB/C macrophages and human intestinal epithelial cells, respectively. We solubilized the above fatty acids and used cell proliferation assays to determine the concentration ranges and specific concentrations of the fatty acids that are not detrimental to human intestinal epithelial cell viability. We solubilized cholera toxin and used it in an assay to determine the concentration ranges and specific concentrations of cholera toxin that do not statistically decrease cell viability in BALB/C macrophages. We found the optimum fatty acid concentrations to be between 1-5 ng/μl, and that for cholera toxin to be cholera infections.

  14. A new method of separation and quantitation of mucus glycoprotein in rat gastric mucus gel layer and its application to mucus secretion induced by 16,16-dimethyl PGE2.

    Science.gov (United States)

    Komuro, Y; Ishihara, K; Ohara, S; Saigenji, K; Hotta, K

    1991-10-01

    A method was established for recovering the mucus gel layer of rat gastric mucosa without damage to underlying surface epithelium. The mucus gel was solubilized by stirring the gastric mucosa in a solution of N-acetylcysteine (NAC), a mucolytic agent. Optimal mucus gel solubilization was possible by treatment with 2% NAC for 5 minutes at room temperature. Mucus glycoprotein was quantitatively extracted and measured from the mucus gel sample obtained by the NAC treatment. This treatment caused no damage to surface epithelial cells, as observed by a light microscope. Besides NAC, pronase solution was also adequate for solubilizing the mucus gel layer without any damage to the surface epithelium. However, extraction and measurement of mucus glycoprotein from the pronase-treated mucus gel sample was not possible due to contamination by high molecular hexose-containing substances which were eluted along with the mucus glycoprotein from the column of Bio-Gel A-1.5m. This NAC method was used to examine changes in mucus glycoprotein content in the mucus gel at one hour following the oral administration of 16,16-dimethyl prostaglandin E2. A significant increase in mucus glycoprotein of the gel was brought about by the prostaglandin treatment. Thus, the present method was suitable for estimating the amount of mucus secreted in to the mucus gel layer.

  15. KDN-containing glycoprotein from loach skin mucus.

    Science.gov (United States)

    Nakagawa, H; Hama, Y; Sumi, T; Li, S C; Li, Y T

    2001-01-01

    It has been widely recognized that the mucus coat of fish plays a variety of important physical, chemical, and physiological functions. One of the major constituents of the mucus coat is mucus glycoprotein. We found that sialic acids in the skin mucus of the loach, Misgurnus anguillicaudatus, consisted predominantly of KDN. Subsequently, we isolated KDN-containing glycoprotein from loach skin mucus and characterized its chemical nature and structure. Loach mucus glycoprotein was purified from the Tris-HCl buffer extract of loach skin mucus by DEAE-cellulose chromatography, Nuclease P1 treatment, and Sepharose CL-6B gel filtration. The purified mucus glycoprotein was found to contain 38.5 KDN, 0.5% NeuAc, 25.0% GalNAc, 3.5% Gal, 0.5% GlcNAc and 28% amino acids. Exhaustive Actinase digestion of the glycoprotein yielded a glycopeptide with a higher sugar content and higher Thr and Ser contents. The molecular size of this glycopeptide was approximately 1/12 of the intact glycoprotein. These results suggest that approximately 11 highly glycosylated polypeptide units are linked in tandem through nonglycosylated peptides to form the glycoporotein molecule. The oligosaccharide alditols liberated from the loach mucus glycoprotein by alkaline borohydride treatment were separated by Sephadex G-25 gel filtration and HPLC. The purified sugar chains were analyzed b --> 6GalNAc-ol, KDNalpha2 --> 3(GalNAcbeta1 --> 14)GalNAc-ol, KDNalpha2 --> 6(GalNAcalpha1 --> 3)GalNAc-ol, KDNalpha2 --> 6(Gal3alpha1--> 3)GalNAc-ol, and NeuAcalpha2 --> 6Gal NAc-ol. It is estimated that one loach mucus glycoprotein molecule contains more than 500 KDN-containing sugar chains that are linked to Thr and Ser residues of the protein core through GalNAc.

  16. In vivo study of the mucus-permeating properties of PEG-coated nanoparticles following oral administration.

    Science.gov (United States)

    Inchaurraga, Laura; Martín-Arbella, Nekane; Zabaleta, Virginia; Quincoces, Gemma; Peñuelas, Ivan; Irache, Juan M

    2015-11-01

    The aim of this work was to investigate the mucus-permeating properties of poly(ethyleneglycol)-coated nanoparticles prepared from the copolymer of methyl vinyl ether and maleic anhydride (Gantrez® AN) after oral administration in rats. Nanoparticles were "decorated" with PEGs of different molecular masses (PEG2000, PEG6000 and PEG10000) at a PEG-to-polymer ratio of 0.125. All the PEG-coated nanoparticles displayed a mean size of ∼150 nm, slightly negative ζ values and a "brush" conformation as determined from the calculation of the PEG density. For in vivo studies, nanoparticles were labelled with either (99m)Tc or fluorescent tags. Naked nanoparticles displayed a higher ability to interact with the mucosa of the stomach than with the small intestine. However, these interactions were restricted to the mucus layer covering the epithelial surface, as visualised by fluorescence microscopy. On the contrary, PEG-coated nanoparticles moved rapidly to the intestine, as determined by imaging, and, then, were capable to develop important interactions with the mucosa, reaching the surface of the epithelium. These mucus permeating properties were more intense for nanoparticles coated with PEG2000 or PEG6000 than with PEG10000. However, the capability of nanocarriers to develop adhesive interactions within the mucosa decreased when prepared at excessive PEG densities.

  17. Investigation of intestinal parasites in pig feces that are also human pathogens.

    Science.gov (United States)

    Uysal, Hayriye Kirkoyun; Boral, Ozden; Metiner, Kemal; Ilgaz, Atilla

    2009-01-01

    A total of 238 pig fecal specimens were collected from pig farms in Corlu (Tekirdağ), Ayazma, and Arnavutköy (Istanbul) during the summer. Out of the 238 pig specimens, 105 were from pigs younger than 6 months and 133 from pigs older than 6 months. These were investigated for intestine parasites in particular the ones that are human pathogens. Cryptosporidium spp. was detected In 21 fecal specimens (8.8%), Giardia spp. in 9 (3.7%), Balantidium coli cysts in 4 (1.6%) and Ascaris suum eggs in 9 (4.1%). Giardia lamblia were found in 8 (7.6%) of 105 pigs younger than 6 months, Cryptosporidium spp. in 12 (11.4%), Balantidium coli cysts in 2 (1.5%). In the pigs older than 6 months Giardia lamblia were found in 1 (0.7%), Cryptosporidium spp. in 9 (6.7%), Balantidium coli cysts in 2 (1.5%). and Ascaris suum eggs in 9 (6.7%). The difference in the rate of G. lamblia (p=0.01) in pigs less than 6 months and of A. suum in those over 6 months was found to be statistically significant (p=0.005). Our results revealed that pigs are important sources of these parasites.

  18. Assessment and Molecular Characterization of Human Intestinal Parasites in Bivalves from Orchard Beach, NY, USA.

    Science.gov (United States)

    Tei, Freda F; Kowalyk, Steven; Reid, Jhenelle A; Presta, Matthew A; Yesudas, Rekha; Mayer, D C Ghislaine

    2016-03-29

    Bivalves have been shown to be carriers of the human intestinal parasites Cryptosporidium parvum and Toxoplasma gondii. The goal of this study is to determine the prevalence of protozoan parasites in mollusks of New York City using a polymerase chain reaction (PCR)-based assay. Four species of mollusks, Mya arenaria, Geukensia demissa, Crassostrea virginica, and Mytilis edulis, were collected from Orchard Beach, NY in the fall of 2014, totaling 159 specimens. Each individual mollusk was dissected to harvest the digestive gland, the mantle, the gills, the foot and the siphon. The tissues were assayed for the presence of Cryptosporidium parvum, Giardia lamblia, and Toxoplasma gondii DNA by using primers that target parasite-specific genes. C. parvum was found at a prevalence of 50%, 11.3%, and 1%, respectively, in Mya arenaria, G. demissa, and Mytilis edulis. C. parvum DNA was detected in all the tissues of these bivalve species, except the gills. Furthermore, G. lamblia was detected in Mya arenaria, G. demissa, Crassostrea virginica and Mytilis edulis at a prevalence of 37.5%, 4.5%, 60%, and 20.6%, respectively, while T. gondii DNA was not detected.

  19. Effects of bariatric surgery on hepatic and intestinal lipoprotein particle metabolism in obese, nondiabetic humans.

    Science.gov (United States)

    Padilla, Nadège; Maraninchi, Marie; Béliard, Sophie; Berthet, Bruno; Nogueira, Juan-Patricio; Wolff, Estelle; Nicolay, Alain; Bégu, Audrey; Dubois, Noémie; Grangeot, Rachel; Mattei, Catherine; Vialettes, Bernard; Xiao, Changting; Lewis, Gary F; Valéro, René

    2014-10-01

    The dyslipidemia of obesity and other insulin-resistant states is characterized by the elevation of plasma triglyceride-rich lipoproteins (TRL) of both hepatic (apoB-100-containing very low-density lipoprotein) and intestinal (apoB-48-containing chylomicrons) origin. Bariatric surgery is a well-established and effective modality for the treatment of obesity and is associated with improvements in several metabolic abnormalities associated with obesity, including a reduction in plasma triglycerides. Here, we have investigated the effect of bariatric surgery on TRL metabolism. Twenty-two nondiabetic, obese subjects undergoing bariatric surgery: sleeve gastrectomy (n=12) or gastric bypass (n=10) were studied. Each subject underwent 1 lipoprotein turnover study 1 month before surgery followed by a second study, 6 months after surgery, using established stable isotope enrichment methodology, in constant fed state. TRL-apoB-100 concentration was significantly reduced after sleeve gastrectomy, explained by a decrease (Psurgery (Pbariatric surgery. This is the first human lipoprotein kinetic study to explore the mechanism of improvement of TRL metabolism after bariatric surgery. These effects may contribute to the decrease of cardiovascular mortality after surgery. http://www.ClinicalTrials.gov. Unique identifier: NCT01277068. © 2014 American Heart Association, Inc.

  20. Regioselective glucuronidation of oxyresveratrol, a natural hydroxystilbene, by human liver and intestinal microsomes and recombinant UGTs.

    Science.gov (United States)

    Hu, Nan; Mei, Mei; Ruan, Jianqing; Wu, Wenjin; Wang, Yitao; Yan, Ru

    2014-01-01

    Oxyresveratrol (OXY) is a natural hydroxystilbene that shows similar bioactivity but better water solubility than resveratrol. This study aims to characterize its glucuronidation kinetics in human liver (HLMs) and intestinal (HIMs) microsomes and identify the main UDP-glucuronosyltransferase (UGT) isoforms involved. Three and four mono-glucuronides of OXY were generated in HIMs and HLMs, respectively, with oxyresveratrol-2-O-β-D-glucuronosyl (G4) as the major metabolite in both organs. The kinetics of G4 formation fit a sigmoidal model in HLMs and biphasic kinetics in HIMs. Multiple UGT isoforms catalyzed G4 formation with the highest activity observed with UGT1A9 followed by UGT1A1. G4 formation by both isoforms followed substrate inhibition kinetics. Propofol (UGT1A9 inhibitor) effectively blocked G4 generation in HLMs (IC50 63.7 ± 11.6 µM), whereas the UGT1A1 inhibitor bilirubin only produced partial inhibition in HLMs and HIMs. These findings shed light on the metabolic mechanism of OXY and arouse awareness of drug interactions.

  1. [Studies on biotransformation of chemical constituents of tongmai formula by human intestinal flora].

    Science.gov (United States)

    Wu, Shuai; Xu, Wei; Yang, Xiu-Wei

    2013-10-01

    To study the chemical constituents in Tongmai formula (TMF) after biotransformation by human intestinal flora (HIF), water extract of TMF was anaerobically incubated with HIF at 37 degrees C. Column chromatographic methods over silica gel, Sephadex LH-20 and semi-preparative high-performance liquid chromatography as well as recrystallization were used to isolate and purify the chemical constituents in TMF after biotransformation by HIF. The chemical structures of isolated compounds were identified on the basis of MS and NMR data. Twenty-six compounds were obtained and identified as phenylpropionic acid (1), 6"-O-acetylpuerarin (2), formononetin(3), daidzein(4), p-hydroxyphenylpropionic acid (5), 3-indolepropionic acid (6), genistein (7), isoformononetin (8), isoononin (9), a mixture of (-)-puerol B-2"-O-glucopyranoside (10a) and (+) -puerol B-2"-O-glucopyranoside (10b), 8-hydroxydaidzein (11), puerol A (12), 3'-methoxy-6"-O-acetylpuerarin (13), 6"-O-acetyldaidzin (14), 3'-methoxydaidzin (15), puerol B (16), 3-methyluracil (17), genistin (18), daidzin (19), 3'-methoxypuerarin (20), mirificin (21), swertiamarin (22) , daidzein-7, 4'-O-glucoside (23), adenine (24), 3'-hydroxypuerarin (25), and puerarin (26). After biotransformation by HIF, the glycosides in TMF were transformed into aglycone and/or less glycosyl compounds along with some hydroxylation and demethylation reactions. Therefore, the glycosides in the TMF are the pro-drug.

  2. In vitro extraction and fermentation of polyphenols from grape seeds (Vitis vinifera) by human intestinal microbiota.

    Science.gov (United States)

    Zhou, Li; Wang, Wei; Huang, Jun; Ding, Yu; Pan, Zhouqiang; Zhao, Ya; Zhang, Renkang; Hu, Bing; Zeng, Xiaoxiong

    2016-04-01

    The effects of several parameters on the extraction yield of total polyphenols from grape seeds by pressurized liquid extraction were investigated. The highest recovery of total polyphenols occurred at 80 °C within 5 min, and a single extraction allowed a recovery of more than 97% of total polyphenols. Following the purification with macroporous resin, the effects of grape polyphenols (>94.8%) on human intestinal microbiota were monitored over 36 h incubation by fluorescence in situ hybridization, and short-chain fatty acids (SCFAs) were measured by HPLC. The result showed that the grape polyphenols promoted the changes in the relevant microbial populations and shifted the profiles of SCFAs. Fermentation of grape polyphenols resulted in a significant increase in the numbers of Bifidobacterium spp. and Lactobacillus-Enterococcus group and inhibition in the growth of the Clostridium histolyticum group and the Bacteroides-Prevotella group, with no significant effect on the population of total bacteria. The findings suggest that grape polyphenols have potential prebiotic effects on modulating the gut microbiota composition and generating SCFAs that contribute to the improvements of host health.

  3. Intestinal parasitic infections and eosinophilia in an human immunedeficiency virus positive population in Honduras

    Directory of Open Access Journals (Sweden)

    Rina G Kaminsky

    2004-11-01

    Full Text Available The occurrence of intestinal parasites, their regional distribution and their relations to eosinophilia were studied in 133 human immunodeficiency virus (HIV positive individuals from Honduras. After signing an informed consent, participants answered a socio-demographic and risk factor questionnaire, a complete physical examination, medical history, and a series of laboratory tests. All participants were HIV positive but not acquired immunodeficiency syndrome positive. Of them, 67% were co-infected with pathogen and non pathogen parasites. Overall occurrence of nematodes was: 44.3% for Trichuris trichiura, 24% for Ascaris lumbricoides, 12% for Hookworm and 7.5% for Strongyloides stercoralis. No cases of Giardia lamblia, acute amebiasis or cryptosporidiasis were diagnosed. Mean eosinophil percents for participants were consistently and significantly higher in infected than in non infected individuals: 22% for Hookworm vs 7.2% (p < 0.001, 11% for Trichuris compared to 5.2% (p < 0.001, 13.2% compared to 7.5% for S. stercoralis (p < 0.05, and 12% compared to 6% for Ascaris cases (p < 0.05. Helminths and non pathogenic protozoa, as single or mixed infections, occurred among the participants. There was a strong correlation between eosinophilia and helminthiasis infections; however, none was identified between CD4 levels and eosinophilia. Because parasitic infections aggravate malnutrition and promote a disbalanced Th2 response in a potentially immuno-compromised host, their effect on HIV disease progression needs further study, mainly in countries were HIV and parasitic infections are highly prevalent.

  4. Reduction of azo dyes and nitroaromatic compounds by bacterial enzymes from the human intestinal tract

    Energy Technology Data Exchange (ETDEWEB)

    Rafii, F.; Cerniglia, C.E. [Food and Drug Administration, Jefferson, AR (United States)

    1995-06-01

    Several anaerobic bacteria from the human intestinal tract are capable of reducing azo dyes and nitropolycyclic aromatic hydrocarbons to the corresponding aromatic amines with enzymes that have azoreductase and nitroreductase activities. The majority of bacteria with these activities belong to the genera Clostridium and Eubacterium. The azoreductases and nitroreductases from three Clostridium strains and one Eubacterium strain were studied. Both enzymes were produced constitutively in each of the bacteria; the enzymes from various bacteria had different electrophoretic mobilities. The azoreductases from all of the bacteria had immunological homology, as was evident from the cross-reactivity of an antibody raised against the azoreductase of C perfringens with azoreductases from other bacteria. Comparison of azoreductases and nitroreductases showed that they both had identical electrophoretic mobilities on polyacrylamide gels and reacted with the antibody against the azoreductase from C. perfringens. Furthermore, the nitroaromatic compounds competitively inhibited the azoreductase activity. The data indicate that the reduction of both nitroaromatic compounds and azo dyes may be carried out by the same enzyme, which is possibly a flavin adenine dinucleotide dehydrogenase that is synthesized throughout the cell and not associated with any organized subcellular structure. 15 refs., 1 fig., 2 tabs.

  5. The influence of pomegranate by-product and punicalagins on selected groups of human intestinal microbiota.

    Science.gov (United States)

    Bialonska, Dobroslawa; Ramnani, Priya; Kasimsetty, Sashi G; Muntha, Kesava R; Gibson, Glenn R; Ferreira, Daneel

    2010-06-15

    We have examined the gut bacterial metabolism of pomegranate by-product (POMx) and major pomegranate polyphenols, punicalagins, using pH-controlled, stirred, batch culture fermentation systems reflective of the distal region of the human large intestine. Incubation of POMx or punicalagins with faecal bacteria resulted in formation of the dibenzopyranone-type urolithins. The time course profile confirmed the tetrahydroxylated urolithin D as the first product of microbial transformation, followed by compounds with decreasing number of phenolic hydroxy groups: the trihydroxy analogue urolithin C and dihydroxylated urolithin A. POMx exposure enhanced the growth of total bacteria, Bifidobacterium spp. and Lactobacillus spp., without influencing the Clostridium coccoides-Eubacterium rectale group and the C. histolyticum group. In addition, POMx increased concentrations of short chain fatty acids (SCFA) viz. acetate, propionate and butyrate in the fermentation medium. Punicalagins did not affect the growth of bacteria or production of SCFA. The results suggest that POMx oligomers, composed of gallic acid, ellagic acid and glucose units, may account for the enhanced growth of probiotic bacteria.

  6. Effect of linear alkylbenzene sulfonate (LAS) on human intestinal Caco-2 cells at non cytotoxic concentrations.

    Science.gov (United States)

    Bradai, Mohamed; Han, Junkyu; Omri, Abdelfatteh El; Funamizu, Naoyuki; Sayadi, Sami; Isoda, Hiroko

    2016-08-01

    Linear alkylbenzene sulfonate (LAS) is a cytotoxic synthetic anionic surfactant widely present in the environment due to its large-scale production and intensive use in the detergency field. In this study, we investigated the effect of LAS (CAS No. 25155-30-0) at non cytotoxic concentrations on human intestinal Caco-2 cells using different in vitro bioassays. As results, LAS increased Caco-2 cell proliferation at concentrations ranging from 1 to 15 ppm, more significantly for shorter exposure time (24 h), confirmed using flow cytometry and trypan blue exclusion methods. Moreover, proteomics analysis revealed that this effect was associated with an over-expression of elongation factor 2 and dipeptidyl peptidase 3, and a down-regulation of 14-3-3 protein theta, confirmed at mRNA level using real-time PCR. These findings suggest that LAS at non cytotoxic concentrations, similar to those observed at wastewater treatment plants outlets, increases the growth rate of colon cancer cells, raising thereby its tumor promotion effect potential.

  7. Prediction of Human intestinal absorption of compounds using artificial intelligence techniques.

    Science.gov (United States)

    Kumar, Rajnish; Sharma, Anju; Siddiqui, Mohammed Haris; Tiwari, Rajesh Kumar

    2017-04-04

    Information about Pharmacokinetics of compounds is an essential component of drug design and development. Modeling the pharmacokinetic properties require identification of the factors effecting absorption, distribution, metabolism and excretion of compounds. There have been continuous attempts in the prediction of absorption of compounds using various Artificial intelligence methods in the effort to reduce the attrition rate of drug candidates entering to preclinical and clinical trials. Currently, there are large numbers of individual predictive models available for absorption using machine learning approaches. In current work, we are presenting a comprehensive study of prediction of absorption. Six Artificial intelligence methods namely, Support vector machine, k- nearest neighbor, Probabilistic neural network, Artificial neural network, Partial least square and Linear discriminant analysis were used for prediction of absorption of compounds with prediction accuracy of 91.54%, 88.33%, 84.30%, 86.51%, 79.07% and 80.08% respectively. Comparative analysis of all the six prediction models suggested that Support vector machine with Radial basis function based kernel is comparatively better for binary classification of compounds using human intestinal absorption and may be useful at preliminary stages of drug design and development. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  8. Transcriptome-wide Analysis Reveals Hallmarks of Human Intestine Development and Maturation In Vitro and In Vivo

    Directory of Open Access Journals (Sweden)

    Stacy R. Finkbeiner

    2015-06-01

    Full Text Available Human intestinal organoids (HIOs are a tissue culture model in which small intestine-like tissue is generated from pluripotent stem cells. By carrying out unsupervised hierarchical clustering of RNA-sequencing data, we demonstrate that HIOs most closely resemble human fetal intestine. We observed that genes involved in digestive tract development are enriched in both fetal intestine and HIOs compared to adult tissue, whereas genes related to digestive function and Paneth cell host defense are expressed at higher levels in adult intestine. Our study also revealed that the intestinal stem cell marker OLFM4 is expressed at very low levels in fetal intestine and in HIOs, but is robust in adult crypts. We validated our findings using in vivo transplantation to show that HIOs become more adult-like after transplantation. Our study emphasizes important maturation events that occur in the intestine during human development and demonstrates that HIOs can be used to model fetal-to-adult maturation.

  9. Factors Affecting the Bioaccessibility and Intestinal Transport of Difenoconazole, Hexaconazole, and Spirodiclofen in Human Caco-2 Cells Following in Vitro Digestion.

    Science.gov (United States)

    Shi, Yan-Hong; Xiao, Jin-Jing; Feng, Rong-Peng; Liu, Yu-Ying; Liao, Min; Wu, Xiang-Wei; Hua, Ri-Mao; Cao, Hai-Qun

    2017-10-04

    This study examined how gastrointestinal conditions affect pesticide bioaccessibility and intestinal transepithelial transport of pesticides (difenoconazole, hexaconazole, and spirodiclofen) in humans. We used an in vitro model combining human gastric and intestinal digestion, followed with Caco-2 cell model for human intestinal absorption. Bioaccessibility of three tested pesticides ranged from 25.2 to 76.3% and 10.6 to 79.63% in the gastric and intestinal phases, respectively. A marked trend similar to the normal distribution was observed between bioaccessibility and pH, with highest values observed at pH 2.12 in gastric juice. No significant differences were observed with increasing digestion time; however, a significant negative correlation was observed with the solid-liquid (S/L) ratio, following a logarithmic equation. R(2) ranged from 0.9198 to 0.9848 and 0.9526 to 0.9951 in the simulated gastric and intestinal juices, respectively, suggesting that the S/L ratio is also a major factor affecting bioaccessibility. Moreover, significant dose- and time-response effects were subsequently observed for intestinal membrane permeability of difenoconazole, but not for hexaconazole or spirodiclofen. This is the first study to demonstrate the uptake of pesticides by human intestinal cells, aiding quantification of the likely effects on human health and highlighting the importance of considering bioaccessibility in studies of dietary exposure to pesticide residues.

  10. Intestinal Ischemia

    Science.gov (United States)

    ... some generally recognized patterns. Symptoms of acute intestinal ischemia Signs and symptoms of acute intestinal ischemia typically ... confusion in older adults Symptoms of chronic intestinal ischemia Signs and symptoms of chronic intestinal ischemia can ...

  11. Improvement in Human Immune Function with Changes in Intestinal Microbiota by Salacia reticulata Extract Ingestion: A Randomized Placebo-Controlled Trial.

    Directory of Open Access Journals (Sweden)

    Yuriko Oda

    Full Text Available Plants belonging to the genus Salacia in the Hippocrateaceae family are known to inhibit sugar absorption. In a previous study, administration of Salacia reticulata extract in rats altered the intestinal microbiota and increased expression of immune-relevant genes in small intestinal epithelial cells. This study aimed to investigate the effect of S. reticulata extract in human subjects by examining the gene expression profiles of blood cells, immunological indices, and intestinal microbiota. The results revealed an improvement in T-cell proliferation activity and some other immunological indices. In addition, the intestinal microbiota changed, with an increase in Bifidobacterium and a decrease in Clostridium bacteria. The expression levels of many immune-relevant genes were altered in blood cells. We concluded that S. reticulata extract ingestion in humans improved immune functions and changed the intestinal microbiota.UMIN Clinical Trials Registry UMIN000011732.

  12. We are not alone: a case for the human microbiome in extra intestinal diseases.

    Science.gov (United States)

    Shivaji, S

    2017-01-01

    "Dysbiosis" in the gut microbiome has been implicated in auto-immune diseases, in inflammatory diseases, in some cancers and mental disorders. The challenge is to unravel the cellular and molecular basis of dysbiosis so as to understand the disease manifestation. Next generation sequencing and genome enabled technologies have led to the establishment of the composition of gut microbiomes and established that "dysbiosis" is the cause of several diseases. In a few cases the cellular and molecular changes accompanying dysbiosis have been investigated and correlated with the disease. Gut microbiome studies have indicated that Christensenella minuta controls obesity in mice, Faecalibacterium prausnitzii protects mice against intestinal inflammation and Akkermansia muciniphila reverses obesity and insulin resistance by secreting endocannabinoids. In mice polysaccharide antigen A on the surface of Bacteroides fragilis, reduces inflammation. Such experiments provide the link between the gut microbiome and human health but implicating dysbiosis with extra-intestinal diseases like arthritis, muscular dystrophy, vaginosis, fibromyalgia, some cancers and mental disorders appears to be more challenging. The relevance of gut microbiome to the eye appears to be very remote. But considering that the eye is the site of inflammatory diseases like uveitis, scleritis, Mooren's corneal ulcer etc. it is possible that these diseases are also influenced by dysbiosis. In mice signals from the gut microbiota activate retina specific T cells that are involved in autoimmune uveitis. Such information would open up new strategies for therapy where the emphasis would be on restoring the diversity in the gut by antibiotic or specific drug use, specific microbe introduction, probiotic use and fecal transplant therapy. The ocular surface microbiome may also be responsible for eye diseases in man but such studies are lacking. Microbiome of the healthy cornea and conjunctiva have been identified. But

  13. Absorption of anthocyanins from blueberry extracts by caco-2 human intestinal cell monolayers.

    Science.gov (United States)

    Yi, Weiguang; Akoh, Casimir C; Fischer, Joan; Krewer, Gerard

    2006-07-26

    Recent studies have shown that dietary polyphenols may contribute to the prevention of cardiovascular disease and cancer. Anthocyanins from different plant sources including blueberries have been shown to possess potential anticancer activities. One of the key factors needed to correctly relate the in vitro study results to human disease outcomes is information about bioavailability. The objectives of the current study were to evaluate the absorption of blueberry anthocyanin extracts using Caco-2 human intestinal cell monolayers and investigate the effects of different aglycones, sugar moieties, and chemical structure on bioavailability of different types of anthocyanins. The results of this study showed that anthocyanins from blueberries could be transported through the Caco-2 cell monolayers although the transport/absorption efficiency was relatively low compared to other aglycone polyphenols. The transport efficiency of anthocyanins averaged approximately 3-4% [less than 1% in delphinidin glucoside (Dp-glc)]. No significant difference in transport/absorption efficiency was observed among three blueberry cultivars. The observed trends among different anthocyanins generally agreed well with some published in vivo results. Dp-glc showed the lowest transport/absorption efficiency, and malvidin glucoside (Mv-glc) showed the highest transport/absorption efficiency. Our result indicates that more free hydroxyl groups and less OCH(3) groups can decrease the bioavailability of anthocyanins. In addition, cyanindin glucoside (Cy-glc) showed significantly higher transport efficiency than cyanidin galactoside (Cy-gal), and peonidin glucoside (Pn-glc) showed significantly higher transport efficiency than peonidin galactoside (Pn-gal), indicating that glucose-based anthocyanins have higher bioavailability than galactose-based anthocyanins.

  14. Impact of Different Fecal Processing Methods on Assessments of Bacterial Diversity in the Human Intestine

    Science.gov (United States)

    Hsieh, Yu-Hsin; Peterson, Courtney M.; Raggio, Anne; Keenan, Michael J.; Martin, Roy J.; Ravussin, Eric; Marco, Maria L.

    2016-01-01

    The intestinal microbiota are integral to understanding the relationships between nutrition and health. Therefore, fecal sampling and processing protocols for metagenomic surveys should be sufficiently robust, accurate, and reliable to identify the microorganisms present. We investigated the use of different fecal preparation methods on the bacterial community structures identified in human stools. Complete stools were collected from six healthy individuals and processed according to the following methods: (i) randomly sampled fresh stool, (ii) fresh stool homogenized in a blender for 2 min, (iii) randomly sampled frozen stool, and (iv) frozen stool homogenized in a blender for 2 min, or (v) homogenized in a pneumatic mixer for either 10, 20, or 30 min. High-throughput DNA sequencing of the 16S rRNA V4 regions of bacterial community DNA extracted from the stools showed that the fecal microbiota remained distinct between individuals, independent of processing method. Moreover, the different stool preparation approaches did not alter intra-individual bacterial diversity. Distinctions were found at the level of individual taxa, however. Stools that were frozen and then homogenized tended to have higher proportions of Faecalibacterium, Streptococcus, and Bifidobacterium and decreased quantities of Oscillospira, Bacteroides, and Parabacteroides compared to stools that were collected in small quantities and not mixed prior to DNA extraction. These findings indicate that certain taxa are at particular risk for under or over sampling due to protocol differences. Importantly, homogenization by any method significantly reduced the intra-individual variation in bacteria detected per stool. Our results confirm the robustness of fecal homogenization for microbial analyses and underscore the value of collecting and mixing large stool sample quantities in human nutrition intervention studies. PMID:27812352

  15. Impact of Different Fecal Processing Methods on Assessments of Bacterial Diversity in the Human Intestine

    Directory of Open Access Journals (Sweden)

    Yu-Hsin Hsieh

    2016-10-01

    Full Text Available The intestinal microbiota are integral to understanding the relationships between nutrition and health. Therefore, fecal sampling and processing protocols for metagenomic surveys should be sufficiently robust, accurate, and reliable to identify the microorganisms present. We investigated the use of different fecal preparation methods on the bacterial community structures identified in human stools. Complete stools were collected from six healthy individuals and processed according to the following methods: (i randomly sampled fresh stool, (ii fresh stool homogenized in a blender for 2 min, (iii randomly sampled frozen stool, and (iv frozen stool homogenized in a blender for 2 min or (v homogenized in a pneumatic mixer for either 10, 20, or 30 min. High-throughput DNA sequencing of the 16S rRNA V4 regions of bacterial community DNA extracted from the stools showed that the fecal microbiota remained distinct between individuals, independent of processing method. Moreover, the different stool preparation approaches did not alter intra-individual bacterial diversity. Distinctions were found at the level of individual taxa, however. Stools that were frozen and then homogenized tended to have higher proportions of Faecalibacterium, Streptococcus, and Bifidobacterium and decreased quantities of Oscillospira, Bacteroides, and Parabacteroides compared to stools that were collected in small quantities and not mixed prior to DNA extraction. These findings indicate that certain taxa are at particular risk for under or over sampling due to protocol differences. Importantly, homogenization by any method significantly reduced the intra-individual variation in bacteria detected per stool. Our results confirm the robustness of fecal homogenization for microbial analyses and underscore the value of collecting and mixing large stool sample quantities in human nutrition intervention studies.

  16. Lactic acid bacteria protect human intestinal epithelial cells from Staphylococcus aureus and Pseudomonas aeruginosa infections.

    Science.gov (United States)

    Affhan, S; Dachang, W; Xin, Y; Shang, D

    2015-12-16

    Staphylococcus aureus and Pseudomonas aeruginosa are opportunistic pathogens that cause nosocomial and food-borne infections. They promote intestinal diseases. Gastrointestinal colonization by S. aureus and P. aeruginosa has rarely been researched. These organisms spread to extra gastrointestinal niches, resulting in increasingly progressive infections. Lactic acid bacteria are Gram