Science.gov

Sample records for intestinal mucosa barrier

  1. Effects of Probiotics on Intestinal Mucosa Barrier in Patients With Colorectal Cancer after Operation

    PubMed Central

    Liu, Dun; Jiang, Xiao-Ying; Zhou, Lan-Shu; Song, Ji-Hong; Zhang, Xuan

    2016-01-01

    Abstract Many studies have found that probiotics or synbiotics can be used in patients with diarrhea or inflammatory bowel disease for the prevention and treatment of some pathologies by improving gastrointestinal barrier function. However, there are few studies availing the use of probiotics in patients with colorectal cancer. To lay the foundation for the study of nutritional support in colorectal cancer patients, a meta-analysis has been carried out to assess the efficacy of probiotics on the intestinal mucosa barrier in patients with colorectal cancer after operation. To estimate the efficacy of probiotics on the intestinal mucosa barrier in patients with colorectal cancer after operation, a meta-analysis of randomized controlled trials has been conducted. Databases including PubMed, Ovid, Embase, the Cochrane Central Register of Controlled Trials, and the China National Knowledge Infrastructure have been searched to identify suitable studies. Stata 12.0 was used for statistical analysis, and sensitivity analysis was also conducted. Six indicators were chosen to evaluate probiotics in protecting the intestinal mucosa barrier in patients with colorectal cancer. Ratios of lactulose to mannitol (L/M) and Bifidobacterium to Escherichia (B/E), occludin, bacterial translocation, and levels of secretory immunoglobulin A (SIgA), interleukin-6 (IL-6), and C-reactive protein (CRP) were chosen to evaluate probiotics in protecting the intestinal mucosa barrier in patients with colorectal cancer. Seventeen studies including 1242 patients were selected for meta-analysis, including 5 English studies and 12 Chinese studies. Significant effects were found in ratios of L/M (standardized mean difference = 3.83, P = 0.001) and B/E (standardized mean difference = 3.91, P = 0.000), occludin (standardized mean difference = 4.74, P = 0.000), bacterial translocation (standardized mean difference = 3.12, P = 0.002), and levels of SIgA (standardized mean

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

    PubMed Central

    Xing, Shen; Zhang, Bolin; Lin, Meng; Zhou, Ping; Li, Jiaolong; Zhang, Lin; Gao, Feng; Zhou, Guanghong

    2017-01-01

    Objective The study was to investigate the effects of alanyl-glutamine (Ala-Gln) and glutamine (Gln) supplementation on the intestinal mucosa barrier in piglets. Methods A total of 180 barrows with initial weight 10.01±0.03 kg were randomly allocated to three treatments, and each treatment consisted of three pens and twenty pigs per pen. The piglets of three groups were fed with control diet [0.62% alanine (Ala)], Ala-Gln diet (0.5% Ala-Gln), Gln diet (0.34% Gln and 0.21% Ala), respectively. Results The results showed that in comparison with control diet, dietary Ala-Gln supplementation increased the height of villi in duodenum and jejunum (p<0.05), Gln supplementation increased the villi height of jejunum (p<0.05), Ala-Gln supplementation up-regulated the mRNA expressions of epidermal growth factor receptor and insulin-like growth factor 1 receptor in jejunal mucosa (p<0.05), raised the mRNA expressions of Claudin-1, Occludin, zonula occludens protein-1 (ZO-1) and the protein levels of Occludin, ZO-1 in jejunal mucosa (p<0.05), Ala-Gln supplementation enlarged the number of goblet cells in duodenal and ileal epithelium (p<0.05), Gln increased the number of goblet cells in duodenal epithelium (p<0.05) and Ala-Gln supplementation improved the concentrations of secretory immunoglobulin A and immunoglobulin G in the jejunal mucosa (p<0.05). Conclusion These results demonstrated that dietary Ala-Gln supplementation could maintain the integrity of small intestine and promote the functions of intestinal mucosa barriers in piglets. PMID:27383799

  3. Effects of Probiotics on Intestinal Mucosa Barrier in Patients With Colorectal Cancer after Operation: Meta-Analysis of Randomized Controlled Trials.

    PubMed

    Liu, Dun; Jiang, Xiao-Ying; Zhou, Lan-Shu; Song, Ji-Hong; Zhang, Xuan

    2016-04-01

    Many studies have found that probiotics or synbiotics can be used in patients with diarrhea or inflammatory bowel disease for the prevention and treatment of some pathologies by improving gastrointestinal barrier function. However, there are few studies availing the use of probiotics in patients with colorectal cancer. To lay the foundation for the study of nutritional support in colorectal cancer patients, a meta-analysis has been carried out to assess the efficacy of probiotics on the intestinal mucosa barrier in patients with colorectal cancer after operation. To estimate the efficacy of probiotics on the intestinal mucosa barrier in patients with colorectal cancer after operation, a meta-analysis of randomized controlled trials has been conducted. Databases including PubMed, Ovid, Embase, the Cochrane Central Register of Controlled Trials, and the China National Knowledge Infrastructure have been searched to identify suitable studies. Stata 12.0 was used for statistical analysis, and sensitivity analysis was also conducted. Six indicators were chosen to evaluate probiotics in protecting the intestinal mucosa barrier in patients with colorectal cancer. Ratios of lactulose to mannitol (L/M) and Bifidobacterium to Escherichia (B/E), occludin, bacterial translocation, and levels of secretory immunoglobulin A (SIgA), interleukin-6 (IL-6), and C-reactive protein (CRP) were chosen to evaluate probiotics in protecting the intestinal mucosa barrier in patients with colorectal cancer. Seventeen studies including 1242 patients were selected for meta-analysis, including 5 English studies and 12 Chinese studies. Significant effects were found in ratios of L/M (standardized mean difference = 3.83, P = 0.001) and B/E (standardized mean difference = 3.91, P = 0.000), occludin (standardized mean difference = 4.74, P = 0.000), bacterial translocation (standardized mean difference = 3.12, P = 0.002), and levels of SIgA (standardized mean

  4. Role of TLR4/NF-κB in Damage to Intestinal Mucosa Barrier Function and Bacterial Translocation in Rats Exposed to Hypoxia

    PubMed Central

    Luo, Han; Guo, Ping; Zhou, Qiquan

    2012-01-01

    The role of Toll-like receptor 4 (TLR4)/nuclear factor-kappa-B (NF-κB) in intestinal mucosal barrier damage and bacterial translocation under hypoxic exposure is unclear. Here, we investigated their role using an acute hypobaric hypoxia model. Adult Sprague-Dawley rats were divided into control (C), hypoxia (H), hypoxia+NF-κB inhibitor pyrrolidinedithiocarbamic acid (PDTC) (100 mg. kg) (HP), hypoxia+0.5 mg/kg lipopolysaccharide (HPL), and hypoxia+PDTC+LPS (HPL) group. Except control group, other four groups were placed in a hypobaric chamber set at 7000 m. Samples were collected at 72 h after pressure reduction. Damage in ultrastructure of the intestinal tract was examined by transmission electron microscopy and bacterial translocation was detected by cultivation. Kinetic turbidimetric assay was used to measure the serum LPS. ELISA was performed to detect TNF-α and IL-6 serum concentrations. Fluorescent quantitative RT-PCR was used to measure TLR4 mRNA levels was measured using quantitative RT-PCR and protein of NF-κB p65 was measured by western blotting. Different degrees of intestinal mucosa damage were observed in groups H and HL. The damage was significantly alleviated after blockage of the TLR4/NF-κB signaling pathway. PDTC- treatment also reversed hyoxia- and LPS-induced bacterial translocation rate and increased serum levels of LPS, TNF-α, and IL-6. TLR4 mRNA levels and NF-κB p65 expression were consistent with the serum factor results. This study suggested that TLR4 and NF-κB expression increased in rat intestinal tissues after acute hypoxia exposure. PDTC-treatment reversed TLR4 and NF-κB upregulation and alleviated damage to the intestinal tract and bacterial translocation. Thus, the TLR4/NF-κB signaling pathway may be critical to the mechanism underlying hypoxia-induced damage to intestinal barrier function and bacterial translocation. PMID:23082119

  5. [Regeneration of the gastric and intestinal mucosas].

    PubMed

    Castrup, H J

    1979-05-10

    The physiological cell renewal of gastrointestinal mucosa is regulated in man as in animal through certain mechanisms with measurable kinetic data. Pathologic mucosal alterations, metabolic disorders, pharmacological agents etc. clearly affect the regenerative processes of the gastrointestinal epithelium. Gastrin and pentagastrin stimulate the growth not only of the parietal cells, but also of the superficial epithelium of the gastric mucosa, whereas secretin does not change cell growth. Glucocorticoid steroids inhibit epithelial regeneration in all parts of the gastrointestinal tract. 5-fluorouracil has a similar effect but acts at a different site in the regeneration cycle. Epithelial cell proliferation of the gastric and intestinal mucosa is likewise inhibited in an uremic condition. In inflammatory changes in the human gastric mucosa epithelial cell hyperproliferation relative to the severity of gastritis and anomalous proliferation within regions of dysplasia can be demonstrated. Foveolary hyperplasia in Ménétrier's disease occurs on the basis of excessive hyperproliferation with displacement of regeneration zones.

  6. Intestinal Barrier and Behavior.

    PubMed

    Julio-Pieper, M; Bravo, J A

    2016-01-01

    The intestinal barrier function contributes to gut homeostasis by modulating absorption of water, electrolytes, and nutrients from the lumen into the circulation while restricting the passage of noxious luminal substances and microorganisms. Chronic conditions such as rheumatoid arthritis, inflammatory bowel disease, and celiac disease are associated to intestinal barrier dysfunction. Here, the hypothesis is that a leaky intestinal wall allowing for indiscriminate passage of intraluminal compounds to the vascular compartment could in turn lead to systemic inflammation. An increasing number of studies are now investigating the association between gut permeability and CNS disorders, under the premise that translocation of intestinal luminal contents could affect CNS function, either directly or indirectly. Still, it is unknown whether disruption of intestinal barrier is a causative agent or a consequence in these situations. Here, we discuss the latest evidence pointing to an association between increased gut permeability and disrupted behavioral responses.

  7. Removal of the intestinal mucosa: photochemical approach in bladder augmentation

    NASA Astrophysics Data System (ADS)

    Haselhuhn, Gregory D.; Kropp, Kenneth A.; Keck, Rick W.; Selman, Steven H.

    1995-03-01

    Experiments were undertaken to determine whether 5-aminoleuvinic acid in combination with light could be used as an adjunct to intestinal bladder augmentation with the aim of removing intestinal mucosa with subsequent re-epithelialization of the treated segment with urothelium. Histopathologic studies of so-treated intestinal segments used in bladder augmentation demonstrate the feasibility of this approach.

  8. Cell volume regulation in goldfish intestinal mucosa.

    PubMed

    Groot, J A

    1981-11-01

    1. Ion and water content of goldfish intestinal mucosa, stripped free from muscular layers were measured under various incubation conditions. 2. Ouabain induces an increase in cation content that is electrically compensated for by chloride. The increase in solute content is accompanied by an increase in water content. 3. When extracellular chloride is partially replaced by sulphate, ouabain does induce cell shrinkage. 4. Anoxia induces a rapid increase in cell volume that is restored by oxygenation of the incubation solution. Ouabain prevents the restoration of volume. 5. It is concluded that the classical ouabain-sensitive Na/K pump participates in the maintenance of cellular volume. We suggest that the constancy in volume after ouabain poisoning as is reported for many tissues might be due to a low chloride conductance of its membranes. 6. Anisotonic media (range: 0.6-1.2 isotonicity), made by variation on mannitol concentration, induce changes in cell water content that deviates from the simplified van't Hoff equation by about 10%. No change in water content after the initial increase was found. 7. We conclude that goldfish enterocytes do not possess a mechanism for rapid volume readjustment.

  9. Effect of toll-like receptor 3 agonist poly I:C on intestinal mucosa and epithelial barrier function in mouse models of acute colitis

    PubMed Central

    Zhao, Hong-Wei; Yue, Yue-Hong; Han, Hua; Chen, Xiu-Li; Lu, Yong-Gang; Zheng, Ji-Min; Hou, Hong-Tao; Lang, Xiao-Meng; He, Li-Li; Hu, Qi-Lu; Dun, Zi-Qian

    2017-01-01

    AIM To investigate potential effects of poly I:C on mucosal injury and epithelial barrier disruption in dextran sulfate sodium (DSS)-induced acute colitis. METHODS Thirty C57BL/6 mice were given either regular drinking water (control group) or 2% (w/v) DSS drinking water (model and poly I:C groups) ad libitum for 7 d. Poly I:C was administrated subcutaneously (20 μg/mouse) 2 h prior to DSS induction in mice of the poly I:C group. Severity of colitis was evaluated by disease activity index, body weight, colon length, histology and myeloperoxidase (MPO) activity, as well as the production of proinflammatory cytokines, including tumor necrosis factor-α (TNF-α), interleukin 17 (IL-17) and interferon-γ (IFN-γ). Intestinal permeability was analyzed by the fluorescein isothiocyanate labeled-dextran (FITC-D) method. Ultrastructural features of the colon tissue were observed under electron microscopy. Expressions of tight junction (TJ) proteins, including zo-1, occludin and claudin-1, were measured by immunohistochemistry/immunofluorescence, Western blot and real-time quantitative polymerase chain reaction (RT-qPCR). RESULTS DSS caused significant damage to the colon tissue in the model group. Administration of poly I:C dramatically protected against DSS-induced colitis, as demonstrated by less body weight loss, lower disease activity index score, longer colon length, colonic MPO activity, and improved macroscopic and histological scores. It also ameliorated DSS-induced ultrastructural changes of the colon epithelium, as observed under scanning electron microscopy, as well as FITC-D permeability. The mRNA and protein expressions of TJ protein, zo-1, occludin and claudin-1 were also found to be significantly enhanced in the poly I:C group, as determined by immunohistochemistry/immunofluorescence, Western blot and RT-qPCR. By contrast, poly I:C pretreatment markedly reversed the DSS-induced up-regulated expressions of the inflammatory cytokines TNF-α, IL-17 and IFN

  10. Effects of n-3 PUFAs on Intestinal Mucosa Innate Immunity and Intestinal Microbiota in Mice after Hemorrhagic Shock Resuscitation

    PubMed Central

    Tian, Feng; Gao, Xuejin; Zhang, Li; Wang, Xinying; Wan, Xiao; Jiang, Tingting; Wu, Chao; Bi, Jingcheng; Lei, Qiucheng

    2016-01-01

    n-3 polyunsaturated fatty acids (PUFAs) can improve the function of the intestinal barrier after damage from ischemia-reperfusion or hemorrhagic shock resuscitation (HSR). However, the effects of n-3 PUFAs on intestinal microbiota and the innate immunity of the intestinal mucosa after HSR remain unclear. In the present study, 40 C57BL/6J mice were randomly assigned to five groups: control, sham, HSR, HSR + n-3 PUFAs and HSR + n-6 PUFAs. Mice were sacrificed 12 h after HSR. Liver, spleen, mesenteric lymph nodes and terminal ileal tissues were collected. Intestinal mucosae were scraped aseptically. Compared with the HSR group, the number of goblet cells increased, expression of mucin 2 was restored and disturbed intestinal microbiota were partly stabilized in the PUFA-administered groups, indicating that both n-3 and n-6 PUFAs reduced overproliferation of Gammaproteobacteria while promoting the growth of Bacteroidetes. Notably, n-3 PUFAs had an advantage over n-6 PUFAs in improving ileal tissue levels of lysozyme after HSR. Thus, PUFAs, especially n-3 PUFAs, partly improved the innate immunity of intestinal mucosa in mice after HSR. These findings suggest a clinical rationale for providing n-3 PUFAs to patients recovering from ischemia-reperfusion. PMID:27690096

  11. Interactions between ingested kaolinite and the intestinal mucosa in rat: proteomic and cellular evidences.

    PubMed

    Reichardt, François; Habold, Caroline; Chaumande, Bertrand; Ackermann, Alain; Ehret-Sabatier, Laurence; Le Maho, Yvon; Angel, Fabielle; Liewig, Nicole; Lignot, Jean-Hervé

    2009-02-01

    Although some of the effects of clay ingestion by humans and animals, such as gastrointestinal wellness and the increase in food efficiency are well known, the underlying mechanisms are not yet fully understood. Therefore, the interactions between the intestinal mucosa and kaolinite particles and their effects on mucosal morphology were observed using light microscopy (LM), transmission electron microscopy (TEM), conventional (CSEM) and environmental (ESEM) scanning electron microscopy combined with an EDX micro-analysis system. Kaolinite consumption, given with free access to rats, varied considerably from one animal to the other but was regular through time for each individual. Some kaolinite particles appeared chemically dissociated in the lumen and within the mucus barrier. Aluminium (Al) originating from ingested clay and present in the mucus layer could directly cross the intestinal mucosa. A significant increase in the thickness of the villi with large vacuoles at the base of the mucosal cells and a decrease in the length of enterocyte microvilli characterized complemented animals. The proteomic analyses of the intestinal mucosa of complemented rats also revealed several modifications in the expression level of cytoskeleton proteins. In summary, kaolinite particles ingested as food complement interact with the intestinal mucosa and modify nutrient absorption. However, these data, together with the potential neurotoxicity of Al, need further investigation.

  12. Dosimetry Model for Radioactivity Localized to Intestinal Mucosa

    SciTech Connect

    Fisher, Darrell R.; Rajon, Didier; Breitz, Hazel B.; Goris, Michael L.; Bolch, Wesley E.; Knox, Susan J.

    2004-06-30

    This paper provides a new model for calculating radiation absorbed dose to the full thickness of the small and large intestinal walls, and to the mucosal layers. The model was used to estimate the intestinal radiation doses from yttrium-90-labeled-DOTA-biotin binding to NR-LU-10-streptavidin in patients. We selected model parameters from published data and observations and used the model to calculate energy absorbed fractions using the EGS4 radiation transport code. We determined the cumulated 90Y activity in the small and large intestines of patients from gamma camera images and calculated absorbed doses to the mucosal layer and to the whole intestinal wall. The mean absorbed dose to the wall of the small intestine was 16.2 mGy/MBq (60 cGy/mCi) administered from 90Y localized in the mucosa and 70 mGy/MBq (260 cGy/mCi) to the mucosal layer within the wall. Doses to the large intestinal wall and to the mucosa of the large intestine were lower than those for small intestine by a factor of about 2.5. These doses are greater by factors of about 5 to 6 than those that would have been calculated using the standard MIRD models that assume the intestinal activity is in the bowel contents. The specific uptake of radiopharmaceuticals in mucosal tissues may lead to dose-related intestinal toxicities. Tissue dosimetry at the sub-organ level is useful for better understanding intestinal tract radiotoxicity and associated dose-response relationships.

  13. Scap is required for sterol synthesis and crypt growth in intestinal mucosa[S

    PubMed Central

    McFarlane, Matthew R.; Cantoria, Mary Jo; Linden, Albert G.; January, Brandon A.; Liang, Guosheng; Engelking, Luke J.

    2015-01-01

    SREBP cleavage-activating protein (Scap) is an endoplasmic reticulum membrane protein required for cleavage and activation of sterol regulatory element-binding proteins (SREBPs), which activate the transcription of genes in sterol and fatty acid biosynthesis. Liver-specific loss of Scap is well tolerated; hepatic synthesis of sterols and fatty acids is reduced, but mice are otherwise healthy. To determine whether Scap loss is tolerated in the intestine, we generated a mouse model (Vil-Scap−) in which tamoxifen-inducible Cre-ERT2, a fusion protein of Cre recombinase with a mutated ligand binding domain of the human estrogen receptor, ablates Scap in intestinal mucosa. After 4 days of tamoxifen, Vil-Scap− mice succumb with a severe enteropathy and near-complete collapse of intestinal mucosa. Organoids grown ex vivo from intestinal crypts of Vil-Scap− mice are readily killed when Scap is deleted by 4-hydroxytamoxifen. Death is prevented when culture medium is supplemented with cholesterol and oleate. These data show that, unlike the liver, the intestine requires Scap to sustain tissue integrity by maintaining the high levels of lipid synthesis necessary for proliferation of intestinal crypts. PMID:25896350

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  16. Intestinal barriers to bacteria and their toxins

    SciTech Connect

    Walker, R.I.; Owen, R.L. )

    1990-01-01

    Immunologic and nonimmunologic processes work together to protect the host from the multitude of microorganisms residing within the intestinal lumen. Mechanical integrity of the intestinal epithelium, mucus in combination with secretory antibody, antimicrobial metabolites of indigenous microorganisms, and peristalsis each limit proliferation and systemic dissemination of enteric pathogens. Uptake of microorganisms by Peyer's patches and other intestinal lymphoid structures and translocation circumvent the mucosal barrier, especially in immunosuppressed individuals. Improved understanding of the composition and limitation of the intestinal barrier, coupled with advances in genetic engineering of immunogenic bacteria, development of oral delivery systems, and immunomodulators, now make enhancement of mucosal barriers feasible. 32 references.

  17. Impedance spectroscopy for monitoring ischemic injury in the intestinal mucosa.

    PubMed

    González, César A; Villanueva, Cleva; Othman, Salah; Narváez, Raúl; Sacristán, Emilio

    2003-05-01

    This work evaluates the feasibility of monitoring ischemic injury in the gastrointestinal mucosa by impedance spectroscopy, using a minimally invasive intestinal catheter. The disruption of the intestinal mucosa plays a key role in the evolution of shock and is the 'motor of multiple organ failure'. Different technologies have been developed to monitor mucosal perfusion, oxygenation and/or ischemia, but no practical method exists to assess tissue damage, which may be crucial for preventing multiple organ failure. The experimental protocol of this study relied on an isobaric model of hypovolemic shock in 16 anaesthetized rabbits assigned to three groups: sham (n = 6), ischemia (n = 5) and ischemia + reperfusion (n = 5). Complex impedance spectra were recorded in the range of 0.05 to 300 kHz, with simultaneous measurements of tonometric pHi in the ileum every 30 min for 4 h. Impedance spectra were reproducible, and those of tissue under prolonged ischemia were clearly differentiable from those of normally perfused tissue. The dynamic changes in impedance did not correlate directly with either tissue perfusion or pHi, but instead correlated well with the duration of ischemia. It is concluded that impedance spectroscopy does indeed measure changes in tissue injury, and could be a very useful tool to guide therapy of patients in shock.

  18. Research Advance in Intestinal Mucosal Barrier and Pathogenesis of Crohn's Disease

    PubMed Central

    Dou, Chuan-zi; Guan, Xin; Wu, Huan-gan

    2016-01-01

    To date, the etiology and pathogenesis of Crohn's disease (CD) have not been fully elucidated. It is widely accepted that genetic, immune, and environment factors are closely related to the development of CD. As an important defensive line for human body against the environment, intestinal mucosa is able to protect the homeostasis of gut bacteria and alleviate the intestinal inflammatory and immune response. It is evident that the dysfunction of intestinal mucosa barriers plays a crucial role in CD initiation and development. Yet researches are insufficient on intestinal mucosal barrier's action in the prevention of CD onset. This article summarizes the research advances about the correlations between the disorders of intestinal mucosal barriers and CD. PMID:27651792

  19. Epidermal Growth Factor and Intestinal Barrier Function

    PubMed Central

    Liu, Hu; Yang, Shufen; Li, Zuohua; Zhong, Jinfeng

    2016-01-01

    Epidermal growth factor (EGF) is a 53-amino acid peptide that plays an important role in regulating cell growth, survival, migration, apoptosis, proliferation, and differentiation. In addition, EGF has been established to be an effective intestinal regulator helping to protect intestinal barrier integrity, which was essential for the absorption of nutrients and health in humans and animals. Several researches have demonstrated that EGF via binding to the EGF receptor and subsequent activation of Ras/MAPK, PI3K/AKT, PLC-γ/PKC, and STATS signal pathways regulates intestinal barrier function. In this review, the relationship between epidermal growth factor and intestinal development and intestinal barrier is described, to provide a better understanding of the effects of EGF on intestine development and health. PMID:27524860

  20. [THE INTESTINAL BARRIER, THE MICROBIOTA, MICROBIOME].

    PubMed

    Mar'yanovich, A T

    2016-01-01

    The review examined modern condition of development directions physiology of digestion, like structure and function of the intestinal barrier, the microbiota of the digestive tract in its relations with the microorganism.

  1. Adhesion of enteroaggregative Escherichia coli to pediatric intestinal mucosa in vitro.

    PubMed Central

    Hicks, S; Candy, D C; Phillips, A D

    1996-01-01

    Organ cultures of small- and large-intestinal mucosa from children were used to examine the interactions of enteroaggregative Escherichia coli (EAEC) with human intestine. Mucosae from patients aged between 3 and 190 months were cultured with five EAEC strains isolated from infants with diarrhea in the United Kingdom and with two well-described prototype EAEC strains, 17-2 and 221. The prototype strains adhered to jejunal, ileal, and colonic mucosae. The wild-type strains also adhered to this tissue but showed a variable pattern of adhesion: two adhered to all intestinal levels, one adhered to jejunum and ileum, one adhered to ileum only, and one adhered to ileum and colon. Adherence was in an aggregative or stacked-brick pattern, resembling that seen on HEp-2 cells. Electron microscopy of infected small intestinal mucosa revealed bacteria in association with a thick mucus layer above an intact enterocyte brush border, which contained extruded cell fragments. This mucus layer was not present on controls. EAEC adherence to colonic mucosa was associated with cytotoxic effects including microvillous vesiculation (but without evidence of an attaching/effacing lesion), enlarged crypt openings, the presence of intercrypt crevices, and increased epithelial cell extrusion. These results demonstrate that in vitro organ culture of intestinal mucosa from children can be used to investigate EAEC pathogenesis in childhood directly. EAEC strains appear able to colonize many regions of the gastrointestinal tract, without overt changes to small intestinal mucosa but with cytotoxic effects on colonic mucosa. PMID:8890236

  2. Characterization of intracellular pteroylpolyglutamate hydrolase (PPH) from human intestinal mucosa

    SciTech Connect

    Wang, T.T.Y.; Chandler, C.J.; Halsted, C.H.

    1986-03-01

    There are two forms of pteroylpolyglutamate hydrolase (PPH) in the human intestinal mucosa, one in the brush border membrane and the other intracellular; brush border PPH is an exopeptidase with optimal activity at pH 6.5 and a requirement for zinc. The presence study characterized human intracellular PPH and compared its properties to those of brush border PPH. Intracellular PPH was purified 30-fold. The enzyme had a MW of 75,000 by gel filtration, was optimally active at pH 4.5, and had an isoelectric point at pH 8.0. In contrast to brush border PPH, intracellular PPH was unstable at increasing temperatures, was unaffected by dialysis against chelating agents and showed no requirement for Zn/sup 2 +/. Using PteGlu/sub 2/(/sup 14/C)Glu as substrate, they demonstrated a K/sub m/ of 1.2 ..mu..M and increasing affinity for folates with longer glutamate chains. Intracellular PPH required the complete folic acid (PteGlu) moiety and a ..gamma..-glutamyl linkage for activity. Using ion exchange chromatography and an HPLC method to determine the hydrolytic products of the reaction, they found intracellular PPH could cleave both internal and terminal ..gamma..-glutamyl linkages, with PteGlu as an end product. After subcellular fractionation of the mucosa, PPH was found in the lysosomes. In summary, the distinct characteristics of brush border and intracellular PPH suggest that the two hydrolases serve different roles in folate metabolism.

  3. Exercise, intestinal barrier dysfunction and probiotic supplementation.

    PubMed

    Lamprecht, Manfred; Frauwallner, Anita

    2012-01-01

    Athletes exposed to high-intensity exercise show an increased occurrence of gastrointestinal (GI) symptoms like cramps, diarrhea, bloating, nausea, and bleeding. These problems have been associated with alterations in intestinal permeability and decreased gut barrier function. The increased GI permeability, a so-called 'leaky gut', also leads to endotoxemia, and results in increased susceptibility to infectious and autoimmune diseases, due to absorption of pathogens/toxins into tissue and the bloodstream. Key components that determine intestinal barrier function and GI permeability are tight junctions, protein structures located in the paracellular channels between epithelial cells of the intestinal wall. The integrity of tight junctions depends on sophisticated interactions between the gut residents and their expressed substances, the intestinal epithelial cell metabolism and the activities of the gut-associated lymphoid tissue. Probiotic supplements are an upcoming group of nutraceuticals that could offer positive effects on athlete's gut and entire health. Some results demonstrate promising benefits for probiotic use on the athlete's immune system. There is also evidence that probiotic supplementation can beneficially influence intestinal barrier integrity in acute diseases. With regard to exercise-induced GI permeability problems, there is still a lack of studies with appropriate data and a gap to understand the underlying mechanisms to support such health beneficial statements implicitly. This article refers (i) to exercise-induced intestinal barrier dysfunction, (ii) provides suggestions to estimate increased gut barrier permeability in athletes, and (iii) discusses the potential of probiotic supplementation to counteract an exercise-induced leaky gut.

  4. Nutritional Keys for Intestinal Barrier Modulation

    PubMed Central

    De Santis, Stefania; Cavalcanti, Elisabetta; Mastronardi, Mauro; Jirillo, Emilio; Chieppa, Marcello

    2015-01-01

    The intestinal tract represents the largest interface between the external environment and the human body. Nutrient uptake mostly happens in the intestinal tract, where the epithelial surface is constantly exposed to dietary antigens. Since inflammatory response toward these antigens may be deleterious for the host, a plethora of protective mechanisms take place to avoid or attenuate local damage. For instance, the intestinal barrier is able to elicit a dynamic response that either promotes or impairs luminal antigens adhesion and crossing. Regulation of intestinal barrier is crucial to control intestinal permeability whose increase is associated with chronic inflammatory conditions. The cross talk among bacteria, immune, and dietary factors is able to modulate the mucosal barrier function, as well as the intestinal permeability. Several nutritional products have recently been proposed as regulators of the epithelial barrier, even if their effects are in part contradictory. At the same time, the metabolic function of the microbiota generates new products with different effects based on the dietary content. Besides conventional treatments, novel therapies based on complementary nutrients are now growing. Fecal therapy has been recently used for the clinical treatment of refractory Clostridium difficile infection instead of the classical antibiotic therapy. In the present review, we will outline the epithelial response to nutritional components derived from dietary intake and microbial fermentation focusing on the consequent effects on the integrity of the epithelial barrier. PMID:26697008

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

    PubMed

    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

  6. Intestinal barrier function in response to abundant or depleted mucosal glutathione in Salmonella-infected rats

    PubMed Central

    van Ampting, Marleen TJ; Schonewille, Arjan J; Vink, Carolien; Brummer, Robert Jan M; Meer, Roelof van der; Bovee-Oudenhoven, Ingeborg MJ

    2009-01-01

    Background Glutathione, the main antioxidant of intestinal epithelial cells, is suggested to play an important role in gut barrier function and prevention of inflammation-related oxidative damage as induced by acute bacterial infection. Most studies on intestinal glutathione focus on oxidative stress reduction without considering functional disease outcome. Our aim was to determine whether depletion or maintenance of intestinal glutathione changes susceptibility of rats to Salmonella infection and associated inflammation. Rats were fed a control diet or the same diet supplemented with buthionine sulfoximine (BSO; glutathione depletion) or cystine (glutathione maintenance). Inert chromium ethylenediamine-tetraacetic acid (CrEDTA) was added to the diets to quantify intestinal permeability. At day 4 after oral gavage with Salmonella enteritidis (or saline for non-infected controls), Salmonella translocation was determined by culturing extra-intestinal organs. Liver and ileal mucosa were collected for analyses of glutathione, inflammation markers and oxidative damage. Faeces was collected to quantify diarrhoea. Results Glutathione depletion aggravated ileal inflammation after infection as indicated by increased levels of mucosal myeloperoxidase and interleukin-1β. Remarkably, intestinal permeability and Salmonella translocation were not increased. Cystine supplementation maintained glutathione in the intestinal mucosa but inflammation and oxidative damage were not diminished. Nevertheless, cystine reduced intestinal permeability and Salmonella translocation. Conclusion Despite increased infection-induced mucosal inflammation upon glutathione depletion, this tripeptide does not play a role in intestinal permeability, bacterial translocation and diarrhoea. On the other hand, cystine enhances gut barrier function by a mechanism unlikely to be related to glutathione. PMID:19374741

  7. Intestinal REG3 Lectins Protect Against Alcoholic Steatohepatitis by Reducing Mucosa-Associated Microbiota and Preventing Bacterial Translocation

    PubMed Central

    Wang, Lirui; Fouts, Derrick E.; Stärkel, Peter; Hartmann, Phillipp; Chen, Peng; Llorente, Cristina; DePew, Jessica; Moncera, Kelvin; Ho, Samuel B.; Brenner, David A.; Hooper, Lora V.; Schnabl, Bernd

    2016-01-01

    Summary Approximately half of all deaths from liver cirrhosis, the 10th leading cause of mortality in the United States, are related to alcohol use. Chronic alcohol consumption is accompanied by intestinal dysbiosis and bacterial overgrowth, yet little is known about the factors that alter the microbial composition or their contribution to liver disease. We previously associated chronic alcohol consumption with lower intestinal levels of the antimicrobial-regenerating islet-derived (REG)-3 lectins. Here, we demonstrate that intestinal deficiency in REG3B or REG3G increases numbers of mucosa-associated bacteria and enhances bacterial translocation to the mesenteric lymph nodes and liver, promoting the progression of ethanol-induced fatty liver disease toward steatohepatitis. Overexpression of Reg3g in intestinal epithelial cells restricts bacterial colonization of mucosal surfaces, reduces bacterial translocation, and protects mice from alcohol-induced steatohepatitis. Thus, alcohol appears to impair control of the mucosa-associated microbiota, and subsequent breach of the mucosal barrier facilitates progression of alcoholic liver disease. PMID:26867181

  8. Cryptosporidium, chronic diarrhoea and the proximal small intestinal mucosa.

    PubMed Central

    Phillips, A D; Thomas, A G; Walker-Smith, J A

    1992-01-01

    The association between Cryptosporidium, chronic diarrhoea and a proximal small intestinal mucosal enteropathy was reviewed over a six and a half year period. One hundred and twenty three children with cryptosporidiosis and no clinical evidence of immune deficiency were identified. 50% of children excreting only Cryptosporidium had chronic diarrhoea. Most cases (63%) of chronic diarrhoea occurred in the first two years of life. A mild to moderate enteropathy was present in all nine children undergoing a small intestinal biopsy and seven showed the presence of Cryptosporidium adhering to villous epithelium. All patients eventually recovered spontaneously. Cryptosporidium is a cause of chronic diarrhoea and a proximal small intestinal mucosal enteropathy in children without immune deficiency. Screening for the parasite should be part of the investigative procedures in children with chronic diarrhoea. Images Figure 4 PMID:1398230

  9. Recombinant Human Epidermal Growth Factor Accelerates Recovery of Mouse Small Intestinal Mucosa After Radiation Damage

    SciTech Connect

    Lee, Kang Kyoo; Jo, Hyang Jeong; Hong, Joon Pio; Lee, Sang-wook Sohn, Jung Sook; Moon, Soo Young; Yang, Sei Hoon; Shim, Hyeok; Lee, Sang Ho; Ryu, Seung-Hee; Moon, Sun Rock

    2008-07-15

    Purpose: To determine whether systemically administered recombinant human epidermal growth factor (rhEGF) accelerates the recovery of mouse small intestinal mucosa after irradiation. Methods and Materials: A mouse mucosal damage model was established by administering radiation to male BALB/c mice with a single dose of 15 Gy applied to the abdomen. After irradiation, rhEGF was administered subcutaneously at various doses (0.04, 0.2, 1.0, and 5.0 mg/kg/day) eight times at 2- to 3-day intervals. The evaluation methods included histologic changes of small intestinal mucosa, change in body weight, frequency of diarrhea, and survival rate. Results: The recovery of small intestinal mucosa after irradiation was significantly improved in the mice treated with a high dose of rhEGF. In the mice that underwent irradiation without rhEGF treatment, intestinal mucosal ulceration, mucosal layer damage, and severe inflammation occurred. The regeneration of villi was noticeable in mice treated with more than 0.2 mg/kg rhEGF, and the villi recovered fully in mice given more than 1 mg/kg rhEGF. The frequency of diarrhea persisting for more than 3 days was significantly greater in the radiation control group than in the rhEGF-treated groups. Conclusions: Systemic administration of rhEGF accelerates recovery from mucosal damage induced by irradiation. We suggest that rhEGF treatment shows promise for the reduction of small intestinal damage after irradiation.

  10. Metabolism of heme and bilirubin in rat and human small intestinal mucosa.

    PubMed Central

    Hartmann, F; Bissell, D M

    1982-01-01

    Formation of heme, bilirubin, and bilirubin conjugates has been examined in mucosal cells isolated from the rat upper small intestine. Intact, viable cells were prepared by enzymatic dissociation using a combined vascular and luminal perfusion and incubated with an isotopically labeled precursor, delta-amino-[2,3-3H]levulinic acid. Labeled heme and bile pigment were formed with kinetics similar to those exhibited by hepatocytes. Moreover, the newly formed bilirubin was converted rapidly to both mono- and diglucuronide conjugates. In addition, cell-free extracts of small intestinal mucosa from rats or humans exhibited a bilirubin-UDP-glucuronyl transferase activity that was qualitatively similar to that present in liver. The data suggest that the small intestinal mucosa normally contributes to bilirubin metabolism. PMID:6806320

  11. Identification of the transcriptional response of human intestinal mucosa to Lactobacillus plantarum WCFS1 in vivo

    PubMed Central

    Troost, Freddy J; van Baarlen, Peter; Lindsey, Patrick; Kodde, Andrea; de Vos, Willem M; Kleerebezem, Michiel; Brummer, Robert-Jan M

    2008-01-01

    Background There is limited knowledge on the extent and dynamics of the mucosal response to commensal and probiotic species in the human intestinal lumen. This study aimed to identify the acute, time-dependent responses of intestinal mucosa to commensal Lactobacillus plantarum WCFS1 in vivo in two placebo-controlled human intervention studies in healthy volunteers. Transcriptional changes in duodenal mucosa upon continuous intraduodenal infusion of L. plantarum WCFS1 for one- and six h, respectively, were studied using oro- and nasogastric intubations with dedicated orogastric catheters and tissue sampling by standard flexible gastroduodenoscopy. Results One- and six-h exposure of small intestinal mucosa to L. plantarum WCFS1 induced differential expression of 669 and 424 gene reporters, respectively. While short-term exposure to L. plantarum WCFS1 inhibited fatty acid metabolism and cell cycle progression, cells switched to a more proliferative phase after prolonged exposure with an overall expression profile characterized by upregulation of genes involved in lipid metabolism, cellular growth and development. Cell death and immune responses were triggered, but cell death-executing genes or inflammatory signals were not expressed. Proteome analysis showed differential expression of several proteins. Only the microsomal protein 'microsomal triglyceride transfer protein' was regulated on both the transcriptional and the protein level in all subjects. Conclusion Overall, this study showed that intestinal exposure to L. plantarum WCFS1 induced consistent, time-dependent transcriptional responses in healthy intestinal mucosa. This extensive exploration of the human response to L. plantarum WCFS1 could eventually provide molecular support for specific or probiotic activity of this strain or species, and exemplifies the strength of the applied technology to identify the potential bio-activity of microbes in the human intestine. PMID:18681965

  12. Misoprostol in the intestinal lumen protects against radiation injury of the mucosa of the small bowel

    SciTech Connect

    Delaney, J.P.; Bonsack, M.E.; Felemovicius, I. )

    1994-03-01

    Systemically administered misoprostol, a PGE analog, has been shown to be an intestinal radioprotector. The purpose of this study was to determine if administration of misoprostol into the intestinal lumen can also reduce the severity of acute radiation enteritis. The rat small bowel was operatively exteriorized and segmented by means of suture ties. The remainder of the intestine and the rat were shielded in a lead box. Misoprostol was introduced into the lumen in various doses. After 30 min exposure to misoprostol, the isolated, exteriorized, segmented bowel was subjected to 11 Gy X irradiation. Five days later the animals were sacrificed and the intestines harvested for evaluation. Surviving crypt numbers per circumference and mucosal height were the criteria used for quantification of damage. Mucosa exposed to misoprostol at the time of radiation delivery showed significantly increased crypt numbers and mucosal height compared to adjacent saline-filled intestine. 24 refs., 2 figs., 2 tabs.

  13. Bile reflux and intestinal metaplasia in gastric mucosa.

    PubMed Central

    Sobala, G M; O'Connor, H J; Dewar, E P; King, R F; Axon, A T; Dixon, M F

    1993-01-01

    AIM: To determine associations between enterogastric bile reflux and gastric mucosal pathology. METHOD: A retrospective study using fasting gastric juice bile acid measurements and antral or prestomal biopsy specimens from 350 patients, 66 of whom had previously undergone surgery that either bypassed or disrupted the pyloric sphincter. RESULTS: Bile reflux was positively associated with reactive gastritis and negatively with Helicobacter pylori density. After stratification for previous surgery, age, and H pylori status, the histological feature most strongly associated with bile reflux was intestinal metaplasia, including all its subtypes. The prevalence of intestinal metaplasia was greatest in patients with both H pylori infection and high bile acid concentrations. Bile reflux was also positively associated with the severity of glandular atrophy, chronic inflammation, lamina propria oedema and foveolar hyperplasia. CONCLUSIONS: Bile reflux is a cause of reactive gastritis. It modifies the features of H pylori associated chronic gastritis. The changes are not confined to patients who have had surgery to their stomachs. The positive associations with atrophy and intestinal metaplasia have implications for models of gastric carcinogenesis. Images PMID:8463417

  14. Dietary cholecalciferol and phosphorus influence intestinal mucosa phytase activity in broiler chicks.

    PubMed

    Onyango, E M; Asem, E K; Adeola, O

    2006-10-01

    1. The role of cholecalciferol and phosphorus in the regulation of intestinal mucosa phytase was investigated in broiler chicks. 2. A total of 144 7-d-old male broiler chicks were grouped by weight into 6 blocks of 4 cages with 6 broiler chicks per cage. Four maize-soybean meal-based mash diets were randomly assigned to cages within each block. The 4 diets consisted of cholecalciferol at 0 or 75 microg/kg and total phosphorus at 3.6 or 7.0 g/kg in a 2 x 2 factorial arrangement. The birds were given the experimental diets for 12 d under conditions which excluded ultraviolet light. 3. Broiler chicks fed on diets with the higher concentration of cholecalciferol had higher Vmax and Km of the mucosa phytase, weight gain, feed intake, feed efficiency and percentage tibia ash, higher ileal digestibility of dry matter, energy, phosphorus (P) and calcium (Ca), and increased retention of dry matter, nitrogen, P, Ca and energy. 4. Broiler chicks receiving diets with the higher P concentration showed lower Vmax and Km of the intestinal mucosa phytase but greater weight gain, feed intake, feed efficiency and percentage tibia ash, higher ileal digestibility of dry matter, energy, P and nitrogen, and increased retention of dry matter, energy, nitrogen and Ca. 5. In conclusion, both dietary P and cholecalciferol influenced the activity of intestinal mucosa phytase.

  15. Subversion of human intestinal mucosa innate immunity by a Crohn's disease-associated E. coli.

    PubMed

    Jarry, A; Crémet, L; Caroff, N; Bou-Hanna, C; Mussini, J M; Reynaud, A; Servin, A L; Mosnier, J F; Liévin-Le Moal, V; Laboisse, C L

    2015-05-01

    Adherent-invasive Escherichia coli (AIEC), associated with Crohn's disease, are likely candidate contributory factors in the disease. However, signaling pathways involved in human intestinal mucosa innate host response to AIEC remain unknown. Here we use a 3D model of human intestinal mucosa explant culture to explore the effects of the AIEC strain LF82 on two innate immunity platforms, i.e., the inflammasome through evaluation of caspase-1 status, and NFκB signaling. We showed that LF82 bacteria enter and survive within a few intestinal epithelial cells and macrophages, without altering the mucosa overall architecture. Although 4-h infection with a Salmonella strain caused crypt disorganization, caspase-1 activation, and mature IL-18 production, LF82 bacteria were unable to activate caspase-1 and induce IL-18 production. In parallel, LF82 bacteria activated NFκB signaling in epithelial cells through IκBα phosphorylation, NFκBp65 nuclear translocation, and TNFα secretion. In addition, NFκB activation was crucial for the maintenance of epithelial homeostasis upon LF82 infection. In conclusion, here we decipher at the whole-mucosa level the mechanisms of the LF82-induced subversion of innate immunity that, by maintaining host cell integrity, ensure intracellular bacteria survival.

  16. Influence of microcystin-LR on the activity of membrane enzymes in rat intestinal mucosa.

    PubMed

    Moreno, I M; Mate, A; Repetto, G; Vázquez, C M; Cameán, A M

    2003-12-01

    The objective of the present study was to evaluate the effects of microcystin-LR (MCLR) on the activity of membrane enzymes from intestinal mucosa. In addition, serum chemistry and peroxidative status of both serum and intestinal homogenate were evaluated after treatment with MCLR. Wistar rats were treated with intraperitoneal injection of either 100 microg pure MCLR/Kg body weight or saline solution. A significant increase in liver weight and altered serum enzyme activities were found in MCLR-treated rats, indicating damage to the liver in these rats, as previously suggested. A higher specific activity of sucrase (1.5-fold) was observed after the administration of MCLR, whereas other intestinal apical membrane enzymes, such as lactase, maltase and alkaline phosphatase were not modified by the treatment. The specific activities of acid phosphatase and succinate dehydrogenase, markers for lysosomal and mitochondrial membranes, respectively, were also increased (32% and 60%, respectively) in treated rats. The analysis of lipid peroxidation showed that the peroxidative status was increased in both serum and intestinal mucosa from MCLR-treated rats, reflecting an excess production of oxygen free radicals induced by this cyanobacterial toxin. In conclusion, this study shows that acute exposure to MCLR affects the intestinal physiology by modifying the intestinal peroxidation status as well as the activity of membrane enzymes.

  17. [The x-ray microanalysis of the mucosa of the rat small intestine].

    PubMed

    Pogorelov, A G; Matys, Iu V

    1990-01-01

    A rat small intestine mucosa is shown to accumulate significant amount of potassium and chloride. There was found a correlation between the content of these chemical elements and glycoprotein compartmentalization in goblet cell secret, brush border of enterocytes and a mucus layer. In this connection a role of mucus glycoproteins in membrane digestion is discussed. For preparation of samples the cryotechniques of electron microscopy are used.

  18. The influence of gut function on lymphoid cell populations in the intestinal mucosa of lambs.

    PubMed Central

    Reynolds, J D; Morris, B

    1983-01-01

    The number and type of lymphoid cells in the intestinal mucosa of lambs change during the first weeks after birth. The influence of gut function on these changes was examined by comparing the evolution of lymphoid cell populations in normal ileum with that in lengths of ileum which had been isolated surgically from the functional intestinal tract of the lamb before birth. The isolated lengths of ileum had a normal blood and nerve supply and they remained healthy throughout a period of at least 2 years, although they did not have a normal histological development. In comparison with normal ileum, the villi of the isolated ileal segments were much smaller and there were many fewer intraepithelial lymphocytes; the lamina propria had significantly fewer lymphocytes than the functional ileum and only a few plasma cells. When isolated ileal segments were reconnected into the intestinal tract after having been isolated from it for 1-3 months, the histology of the mucosa reverted to that of the normal gut, with the same number and types of lymphoid cells. Radiolabelled lymphoblasts collected from intestinal lymph and injected intravenously accumulated to only a small extent in isolated segments of ileum compared with either the normal or the reconnected segments of ileum. This suggested that the paucity of lymphocytes in the mucosa of the isolated segments was due to a reduced extravasation of these cells there. The influence which the gut contents exert on the lymphoid cell population in the mucosa is probably associated with antigenic stimulation but may also be related to other factors concerned in the normal digestive functions of the gut. Images Figure 1 Figure 2 Figure 3 PMID:6862523

  19. Effect of cholera enterotoxin on carbohydrate metabolism in the liver and small intestinal mucosa of rabbits

    SciTech Connect

    Vengrov, P.R.; Cherkasova, T.D.; Yurkiv, V.A.; Pokrovskii, V.I.

    1987-09-01

    The effect of cholera enterotoxin injected in vivo on glucose formation from alanine, and also on glucose-6-phosphatase activity in the liver and mucosa of the small intestine was studied. L-(2,3-/sup 3/H)-alanine was added to the incubation medium. Chromatograms were developed with 5% AgNO/sub 3/ with the addition of an aqueous solution of ammonia. The quantity of radioactive glucose was determined in a scintillation counter.

  20. Establishment and evaluation of an experimental rat model for high-altitude intestinal barrier injury

    PubMed Central

    Luo, Han; Zhou, Dai-Jun; Chen, Zhang; Zhou, Qi-Quan; Wu, Kui; Tian, Kun; Li, Zhi-Wei; Xiao, Zhen-Liang

    2017-01-01

    In the present study an experimental high-altitude intestinal barrier injury rat model was established by simulating an acute hypoxia environment, to provide an experimental basis to assess the pathogenesis, prevention and treatment of altitude sickness. A total of 70 healthy male Sprague-Dawley rats were divided into two groups: Control group (group C) and a high-altitude hypoxia group (group H). Following 2 days adaptation, the rats in group H were exposed to a simulated 4,000-m, high-altitude hypoxia environment for 3 days to establish the experimental model. To evaluate the model, bacterial translocation, serum lipopolysaccharide level, pathomorphology, ultrastructure and protein expression in rats were assessed. The results indicate that, compared with group C, the rate of bacterial translocation and the apoptotic index of intestinal epithelial cells were significantly higher in group H (P<0.01). Using a light microscope it was determined that the intestinal mucosa was thinner in group H, there were fewer epithelial cells present and the morphology was irregular. Observations with an electron microscope indicated that the intestinal epithelial cells in group H were injured, the spaces among intestinal villi were wider, the tight junctions among cells were open and lanthanum nitrate granules (from the fixing solution) had diffused into the intestinal mesenchyme. The expression of the tight junction protein occludin was also decreased in group H. Therefore, the methods applied in the present study enabled the establishment of a stable, high-altitude intestinal barrier injury model in rats. PMID:28352318

  1. Ghrelin Attenuates Intestinal Barrier Dysfunction Following Intracerebral Hemorrhage in Mice

    PubMed Central

    Cheng, Yijun; Wei, Yongxu; Yang, Wenlei; Cai, Yu; Chen, Bin; Yang, Guoyuan; Shang, Hanbing; Zhao, Weiguo

    2016-01-01

    Intestinal barrier dysfunction remains a critical problem in patients with intracerebral hemorrhage (ICH) and is associated with poor prognosis. Ghrelin, a brain-gut peptide, has been shown to exert protection in animal models of gastrointestinal injury. However, the effect of ghrelin on intestinal barrier dysfunction post-ICH and its possible underlying mechanisms are still unknown. This study was designed to investigate whether ghrelin administration attenuates intestinal barrier dysfunction in experimental ICH using an intrastriatal autologous blood infusion mouse model. Our data showed that treatment with ghrelin markedly attenuated intestinal mucosal injury at both histomorphometric and ultrastructural levels post-ICH. Ghrelin reduced ICH-induced intestinal permeability according to fluorescein isothiocyanate conjugated-dextran (FITC-D) and Evans blue extravasation assays. Concomitantly, the intestinal tight junction-related protein markers, Zonula occludens-1 (ZO-1) and claudin-5 were upregulated by ghrelin post-ICH. Additionally, ghrelin reduced intestinal intercellular adhesion molecule-1 (ICAM-1) expression at the mRNA and protein levels following ICH. Furthermore, ghrelin suppressed the translocation of intestinal endotoxin post-ICH. These changes were accompanied by improved survival rates and an attenuation of body weight loss post-ICH. In conclusion, our results suggest that ghrelin reduced intestinal barrier dysfunction, thereby reducing mortality and weight loss, indicating that ghrelin is a potential therapeutic agent in ICH-induced intestinal barrier dysfunction therapy. PMID:27929421

  2. A proteomic adaptation of small intestinal mucosa in response to dietary protein limitation

    PubMed Central

    Qin, Chunfu; Qiu, Kai; Sun, Wenjuan; Jiao, Ning; Zhang, Xin; Che, Lianqiang; Zhao, Haiyi; Shen, Hexiao; Yin, Jingdong

    2016-01-01

    Dietary protein limitation (PL) is not only beneficial to human health but also applied to minimize nitrogen excretion in livestock production. However, the impact of PL on intestinal physiology is largely unknown. In this study, we identified 5275 quantitative proteins using a porcine model in which pigs suffered PL. A total of 202 proteins |log2 fold-change| > 1 were taken as differentially expressed proteins and subjected to functional and pathway enrichment analysis to reveal proteomic alterations of the jejunal mucosa. Combining with the results of western blotting analysis, we found that protein/carbohydrate digestion, intestinal mucosal tight junction and cell adhesion molecules, and the immune response to foreign antigens were increased in the jejunal mucosa of the pigs upon PL. In contrast, amino acid transport, innate and auto immunity, as well as cell proliferation and apoptosis were reduced. In addition, the expression of functional proteins that involved in DNA replication, transcription and mRNA splicing as well as translation were altered in the jejunal mucosa in response to PL. Furthermore, PL may reduce amino acid transport and cell proliferation through the depression of mTOR pathway. This study provides new insights into the molecular mechanisms underlying the small intestinal response to PL. PMID:27841298

  3. Berberine Reduces Uremia-Associated Intestinal Mucosal Barrier Damage.

    PubMed

    Yu, Chao; Tan, Shanjun; Zhou, Chunyu; Zhu, Cuilin; Kang, Xin; Liu, Shuai; Zhao, Shuang; Fan, Shulin; Yu, Zhen; Peng, Ai; Wang, Zhen

    2016-11-01

    Berberine is one of the main active constituents of Rhizoma coptidis, a traditional Chinese medicine, and has long been used for the treatment of gastrointestinal disorders. The present study was designed to investigate the effects of berberine on the intestinal mucosal barrier damage in a rat uremia model induced by the 5/6 kidney resection. Beginning at postoperative week 4, the uremia rats were treated with daily 150 mg/kg berberine by oral gavage for 6 weeks. To assess the intestinal mucosal barrier changes, blood samples were collected for measuring the serum D-lactate level, and terminal ileum tissue samples were used for analyses of intestinal permeability, myeloperoxidase activity, histopathology, malondialdehyde (MDA) level, and superoxide dismutase (SOD) activity. Berberine treatment resulted in significant decreases in the serum D-lactate level, intestinal permeability, intestinal myeloperoxidase activity, and intestinal mucosal and submucosal edema and inflammation, and the Chiu's scores assessed for intestinal mucosal injury. The intestinal MDA level was reduced and the intestinal SOD activity was increased following berberine treatment. In conclusion, berberine reduces intestinal mucosal barrier damage induced by uremia, which is most likely due to its anti-oxidative activity. It may be developed as a potential treatment for preserving intestinal mucosal barrier function in patients with uremia.

  4. Inflammation and the Intestinal Barrier: Leukocyte–Epithelial Cell Interactions, Cell Junction Remodeling, and Mucosal Repair

    PubMed Central

    Luissint, Anny-Claude; Parkos, Charles A.; Nusrat, Asma

    2017-01-01

    The intestinal tract is lined by a single layer of columnar epithelial cells that forms a dynamic, permeable barrier allowing for selective absorption of nutrients, while restricting access to pathogens and food-borne antigens. Precise regulation of epithelial barrier function is therefore required for maintaining mucosal homeostasis and depends, in part, on barrier-forming elements within the epithelium and a balance between pro- and anti-inflammatory factors in the mucosa. Pathologic states, such as inflammatory bowel disease, are associated with a leaky epithelial barrier, resulting in excessive exposure to microbial antigens, recruitment of leukocytes, release of soluble mediators, and ultimately mucosal damage. An inflammatory microenvironment affects epithelial barrier properties and mucosal homeostasis by altering the structure and function of epithelial intercellular junctions through direct and indirect mechanisms. We review our current understanding of complex interactions between the intestinal epithelium and immune cells, with a focus on pathologic mucosal inflammation and mechanisms of epithelial repair. We discuss leukocyte–epithelial interactions, as well as inflammatory mediators that affect the epithelial barrier and mucosal repair. Increased knowledge of communication networks between the epithelium and immune system will lead to tissue-specific strategies for treating pathologic intestinal inflammation. PMID:27436072

  5. IBD Candidate Genes and Intestinal Barrier Regulation

    PubMed Central

    McCole, Declan F.

    2015-01-01

    Technological advances in the large scale analysis of human genetics have generated profound insights into possible genetic contributions to chronic diseases including the inflammatory bowel diseases (IBDs), Crohn’s disease and ulcerative colitis. To date, 163 distinct genetic risk loci have been associated with either Crohn’s disease or ulcerative colitis, with a substantial degree of genetic overlap between these 2 conditions. Although many risk variants show a reproducible correlation with disease, individual gene associations only affect a subset of patients, and the functional contribution(s) of these risk variants to the onset of IBD is largely undetermined. Although studies in twins have demonstrated that the development of IBD is not mediated solely by genetic risk, it is nevertheless important to elucidate the functional consequences of risk variants for gene function in relevant cell types known to regulate key physiological processes that are compromised in IBD. This article will discuss IBD candidate genes that are known to be, or are suspected of being, involved in regulating the intestinal epithelial barrier and several of the physiological processes presided over by this dynamic and versatile layer of cells. This will include assembly and regulation of tight junctions, cell adhesion and polarity, mucus and glycoprotein regulation, bacterial sensing, membrane transport, epithelial differentiation, and restitution. PMID:25215613

  6. A surface energy analysis of mucoadhesion: contact angle measurements on polycarbophil and pig intestinal mucosa in physiologically relevant fluids.

    PubMed

    Lehr, C M; Bouwstra, J A; Boddé, H E; Junginger, H E

    1992-01-01

    The possible role of surface energy thermodynamics in mucoadhesion was investigated with Polycarbophil and pig intestinal mucosa. In separate experiments, the surface energy parameters of the substrate (mucosa) and the adhesive (polymer film) were determined by contact angle measurements on captive air/octane bubbles in three physiologically relevant test fluids (isotonic saline, artificial gastric fluid, and artificial intestinal fluid). Whereas the swollen Polycarbophil films were relatively hydrophilic as indicated by small water contact angles (22, 23, and 16 degrees), the water contact angles measured on mucosal tissue were significantly larger (61, 48, and 57 degrees). Hence, mucus was found to possess an appreciable hydrophobicity. The measured adhesive performance (force of detachment) between Polycarbophil and pig small intestinal mucosa was highest in nonbuffered saline medium, intermediate in gastric fluid, and minimal in intestinal fluid. In agreement with this trend, the mismatch in surface polarities between substrate and adhesive, calculated from the contact angle data, increased in the same order.

  7. [Role of antimicrobial peptides (AMP) and pattern recognition receptors (PRR) in the intestinal mucosa homeostasis].

    PubMed

    Lapis, Károly

    2009-11-22

    Homeostasis and integrity of bowel mucosa is assured by well controlled mechanical, biochemical and immunological mechanisms. First line of defense is presented by the antimicrobial peptides (AMP), which form a continuous layer on the bowel surface, produced by intestinal specific (Paneth) and non-specific epithelial cells. AMPs have a significant antimicrobial, antifungal and antiviral, as well as immunomodulatory effects. Next line of defense is the pattern recognition receptors (PRR), which allows identifying conservative molecular patterns of different pathogens, and starts antimicrobial and inflammatory mechanisms through gene-expression induction. We review the most recent knowledge and studies concerning these mechanisms.

  8. They Must Hold Tight: Junction Proteins, Microbiota And Immunity In Intestinal Mucosa.

    PubMed

    Castoldi, Angela; Favero de Aguiar, Cristhiane; Moraes-Vieira, Pedro Manoel; Olsen Saraiva Câmara, Niels

    2015-01-01

    Homeostasis of the immune system depends on several factors. The gastrointestinal tract plays an important role in maintaining our immune system. With this aim, the intestinal immune system interacts with epithelial barrier molecules, especially tight junction proteins, that are key molecules involved in controlling paracellular permeability to increase the protection barrier against external antigens or possibly to respond to commensal microorganisms. During intestinal inflammatory diseases, the expression of innate immune receptors in intestinal epithelial cells and infiltration of immune cells are related, but it is still unclear how the immune system induces modulation of paracellular permeability. In this review, we provide an overview of the understanding of how the immune system modulates the expression of tight junctions to maintain the mucosal immune system.

  9. Long noncoding RNA SPRY4-IT1 regulates intestinal epithelial barrier function by modulating the expression levels of tight junction proteins.

    PubMed

    Xiao, Lan; Rao, Jaladanki N; Cao, Shan; Liu, Lan; Chung, Hee Kyoung; Zhang, Yun; Zhang, Jennifer; Liu, Yulan; Gorospe, Myriam; Wang, Jian-Ying

    2016-02-15

    Epithelial cells line the intestinal mucosa and form an important barrier to a wide array of noxious substances in the lumen. Disruption of the barrier integrity occurs commonly in various pathologies. Long noncoding RNAs (lncRNAs) control diverse biological processes, but little is known about the role of lncRNAs in regulation of the gut permeability. Here we show that the lncRNA SPRY4-IT1 regulates the intestinal epithelial barrier function by altering expression of tight junction (TJ) proteins. SPRY4-IT1 silencing led to dysfunction of the epithelial barrier in cultured cells by decreasing the stability of mRNAs encoding TJ proteins claudin-1, claudin-3, occludin, and JAM-1 and repressing their translation. In contrast, increasing the levels of SPRY4-IT1 in the intestinal mucosa protected the gut barrier in mice exposed to septic stress by increasing the abundance of TJ proteins. SPRY4-IT1 directly interacted with TJ mRNAs, and this process was enhanced through the association with the RNA-binding protein HuR. Of interest, the intestinal mucosa from patients with increased gut permeability exhibited a decrease in the levels of SPRY4-IT1. These findings highlight a novel role for SPRY4-IT1 in controlling the intestinal epithelial barrier and define a mechanism by which SPRY4-IT1 modulates TJ expression by altering the stability and translation of TJ mRNAs.

  10. Long noncoding RNA SPRY4-IT1 regulates intestinal epithelial barrier function by modulating the expression levels of tight junction proteins

    PubMed Central

    Xiao, Lan; Rao, Jaladanki N.; Cao, Shan; Liu, Lan; Chung, Hee Kyoung; Zhang, Yun; Zhang, Jennifer; Liu, Yulan; Gorospe, Myriam; Wang, Jian-Ying

    2016-01-01

    Epithelial cells line the intestinal mucosa and form an important barrier to a wide array of noxious substances in the lumen. Disruption of the barrier integrity occurs commonly in various pathologies. Long noncoding RNAs (lncRNAs) control diverse biological processes, but little is known about the role of lncRNAs in regulation of the gut permeability. Here we show that the lncRNA SPRY4-IT1 regulates the intestinal epithelial barrier function by altering expression of tight junction (TJ) proteins. SPRY4-IT1 silencing led to dysfunction of the epithelial barrier in cultured cells by decreasing the stability of mRNAs encoding TJ proteins claudin-1, claudin-3, occludin, and JAM-1 and repressing their translation. In contrast, increasing the levels of SPRY4-IT1 in the intestinal mucosa protected the gut barrier in mice exposed to septic stress by increasing the abundance of TJ proteins. SPRY4-IT1 directly interacted with TJ mRNAs, and this process was enhanced through the association with the RNA-binding protein HuR. Of interest, the intestinal mucosa from patients with increased gut permeability exhibited a decrease in the levels of SPRY4-IT1. These findings highlight a novel role for SPRY4-IT1 in controlling the intestinal epithelial barrier and define a mechanism by which SPRY4-IT1 modulates TJ expression by altering the stability and translation of TJ mRNAs. PMID:26680741

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

    PubMed Central

    Onal, Ozkan; Yetisir, Fahri; Sarer, A. Ebru Salman; Zeybek, N. Dilara; Onal, C. Oztug; Yurekli, Banu; Celik, H. Tugrul; Sirma, Ayse; Kılıc, Mehmet

    2015-01-01

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

  12. Human Intestinal Barrier Function in Health and Disease

    PubMed Central

    König, Julia; Wells, Jerry; Cani, Patrice D; García-Ródenas, Clara L; MacDonald, Tom; Mercenier, Annick; Whyte, Jacqueline; Troost, Freddy; Brummer, Robert-Jan

    2016-01-01

    The gastrointestinal tract consists of an enormous surface area that is optimized to efficiently absorb nutrients, water, and electrolytes from food. At the same time, it needs to provide a tight barrier against the ingress of harmful substances, and protect against a reaction to omnipresent harmless compounds. A dysfunctional intestinal barrier is associated with various diseases and disorders. In this review, the role of intestinal permeability in common disorders such as infections with intestinal pathogens, inflammatory bowel disease, irritable bowel syndrome, obesity, celiac disease, non-celiac gluten sensitivity, and food allergies will be discussed. In addition, the effect of the frequently prescribed drugs proton pump inhibitors and non-steroidal anti-inflammatory drugs on intestinal permeability, as well as commonly used methods to assess barrier function will be reviewed. PMID:27763627

  13. The effect of P-glycoprotein on methadone hydrochloride flux in equine intestinal mucosa.

    PubMed

    Linardi, R L; Stokes, A M; Andrews, F M

    2013-02-01

    Methadone is an effective analgesic opioid that may have a place for the treatment of pain in horses. However, its absorption seems to be impaired by the presence of a transmembrane protein, P-glycoprotein, present in different tissues including the small intestine in other species. This study aims to determine the effect of the P-glycoprotein on methadone flux in the equine intestinal mucosa, as an indicator of in vivo drug absorption. Jejunum tissues from five horses were placed into the Ussing chambers and exposed to methadone solution in the presence or absence of Rhodamine 123 or verapamil. Electrical measurements demonstrated tissue viability for 120 min, and the flux of methadone across the jejunal membrane (mucosal to submucosal direction) was calculated based on the relative drug concentration measured by ELISA. The flux of methadone was significantly higher only in the presence of verapamil. P-glycoprotein was immunolocalized in the apical membrane of the jejunal epithelial cells (enterocytes), mainly located in the tip of the villi compared to cells of the crypts. P-glycoprotein is present in the equine jejunum and may possibly mediate the intestinal transport of methadone. This study suggests that P-glycoprotein may play a role in the poor intestinal absorption of methadone in vivo.

  14. Regeneration of the intestinal mucosa in Eimeria and E. Coli challenged broilers supplemented with amino acids.

    PubMed

    Gottardo, E T; Prokoski, K; Horn, D; Viott, A D; Santos, T C; Fernandes, J I M

    2016-05-01

    The aim of this study was to evaluate the regeneration of the intestinal mucosa in Eimeria and E. coli challenged broilers supplemented with glutamine, arginine, and threonine. Six hundred male broilers at one d of age from the Cobb strain were utilized. The design was completely randomized using a 2×3 factorial design (unchallenged and challenged and 3 diets). A commercial diet was used as a control and 2 other diets were formulated with glutamine (1.5 and 3% Aminogut®), arginine (1 and 2% L-Arginine), and threonine (1 and 2% L-threonine). The animals that consumed diets supplemented with amino acids presented better (P<0.05) feed conversion in the period from one to 42 d of age. The ability of cell proliferation and the villus:crypt ratio in response to enteric challenge were greater (P<0.05) for broilers that received diets supplemented with amino acids. High levels of amino acids in the experimental feeds reflected in greater protein levels in poultry house litter, and they did not interfere with ammonia production. The supplementation of diets with trophic amino acids can positively contribute to the regeneration and proliferation of the intestinal mucosa in broilers and to the maintenance of zootechnical performance when submitted to enteric challenges.

  15. Pharmaceutical drugs supporting regeneration of small-intestinal mucosa severely damaged by ionizing radiation in mice

    PubMed Central

    Ishihara, Hiroshi; Tanaka, Izumi; Yakumaru, Haruko; Tanaka, Mika; Yokochi, Kazuko; Akashi, Makoto

    2013-01-01

    Accidental exposure of the abdomen to high-dose radiation leads to severe consequences initiated by disruption of the mucosa in the small intestine. Therapeutic options are limited, even though various treatments have been investigated, particularly in the field of regenerative therapy. In order to identify readily available treatment methods, we included several current pharmaceutical drugs, for which the clinical trials have already been completed, in tests on mice that had undergone severe mucosal damage by radiation. The drugs were injected into mice 24 h after exposure to 15.7 Gy X-rays. The effects of the drugs on the damaged mucosa of the small intestine were evaluated using early regeneration indices [the expression of c-myb mRNA, and proliferation of epithelial cells in the form of microcolonies (MCs) by Days 4 and 5 post-irradiation] and the survival rate of the mice. Enhancement of mucosal regeneration at Day 4 (c-myb: P < 0.01, MC: P < 0.05) and improvement of the survival rate (P < 0.05) were observed when a clinical dose of gonadotropin, a stimulator of androgen, was injected. Similarly, a clinical dose of thiamazole (which prevents secretion of thyroid hormone) stimulated mucosal growth by Day 5 (c-myb: P < 0.01, MC: P < 0.05) and also improved the survival rate (P < 0.05). The nonclinical drugs histamine and high-dose octreotide (a growth hormone antagonist) also gave significant survival-enhancing benefits (P < 0.01 and P < 0.05, respectively). These results can be used to construct therapeutic programs and applied in various experimental studies to control the regeneration of damaged mucosa. PMID:23728323

  16. Intestinal metaplasia of the stomach and esophagus: an immunohistochemical study of 60 cases including comparison with normal and inflamed intestinal mucosa.

    PubMed

    Chlumská, Alena; Mukenšnabl, Petr; Mareček, Petr; Zámečník, Michal

    2014-07-01

    Recently, a new classification of intestinal metaplasia (IM) using immunohistochemical mucin markers was proposed. Two following types of IM were defined: (1) a mixed gastric and intestinal type also called incomplete IM; (2) a purely intestinal type, also called complete IM. We present a series of 30 cases of gastric IM and 30 cases of IM of the esophagus, using this new classification. In all gastric cases, IM developed in the mucus-neck region in the form of incomplete IM. Toward the mucosa surface, it matured gradually into complete IM. This maturation showed a gradual reduction of both foveolar mucin MUC5AC and pyloric gland mucin MUC6. In two of 30 cases, IM was of the incomplete hyperproliferative type. In one case, focal high-grade adenomatous dysplasia was found in the incomplete IM. In the esophageal cases, IM was found in inflamed cardiac-type mucosa, and it was usually of the incomplete type, with almost diffuse positivity for MUC5AC and with rare positivity of MUC6. The goblet cells and some cylindrical cells expressed intestinal mucin MUC2. The proliferation was higher than in the complete IM, and in one case, focal low grade adenomatous dysplasia was found. In addition, we examined the expression of mucins in normal and inflamed intestinal mucosa. These cases included 50 duodenal biopsies, 50 biopsies from the ileum, and 50 biopsies from the colon. The inflamed cases included celiac disease, Crohn's disease, and ulcerative colitis. Some goblet cells of the normal intestinal mucosa expressed both MUC2 and MUC5AC. More numerous MUC5AC+ goblet cells were found in the inflamed intestinal mucosa. In the duodenal and small intestinal mucosa, even the MUC6 positivity of a few goblet or cylindrical cells was found. In sum, our results indicate that incomplete IM is an initial step of the metaplastic process. It can mature into complete IM, or alternatively, it can develop dysplasia or adenocarcinoma. In addition, we found that gastric-type mucins are also

  17. Gliadin-dependent cytokine production in a bidimensional cellular model of celiac intestinal mucosa.

    PubMed

    Vincentini, Olimpia; Maialetti, Francesca; Gonnelli, Elena; Silano, Marco

    2015-11-01

    The downstream cascade of the inflammatory response to gliadin in celiac intestinal mucosa encompasses the early activation of the innate immunity that triggers the adaptive response. Therefore, the in vitro study of the pathogenic mechanism of celiac disease (CD) on enterocytes alone or mucosal T lymphocytes alone does not fully consider all the aspects of gliadin-dependent inflammation. Although the in vitro culture of specimens of intestinal mucosa obtained from celiac patients is the gold standard for the study of CD, this technique presents several technical challenges and the bioptic specimens are not easily available. So, in this paper, we described the gliadin-dependent cytokine production in a bidimensional cellular system, which is able to mimic both the innate and the adaptive steps of the mucosal immune response of CD. In the upper compartment, the intestinal epithelial cells are grown on a filter, and in the lower compartment, the mononuclear cells isolated from peripheral blood of celiac patients are cultured. Cells were apically exposed to the toxic gliadin peptide p31-43 for 3 h and then with the immunodominant gliadin fragment pα-9 for 21 h. The incubation with gliadin peptides resulted in increased levels of IL-15, INF-γ, IL-6, tumor necrosis factor (TNF)-α, IL-1β, and CCL 2, 3 and 4 in the basal supernatants, with respect to cells exposed to medium alone. The p31-43-driven epithelial priming of mucosal response consists of transglutaminase (TG2)-mediated deamidation of the immunostimulatory gliadin peptides, as demonstrated by the inhibition of pα-9 activity, when the system is exposed to blocking anti-TG2 antibody.

  18. Modulation of intestinal barrier by intestinal microbiota: pathological and therapeutic implications.

    PubMed

    Natividad, Jane M M; Verdu, Elena F

    2013-03-01

    Mammals and their intestinal microbiota peacefully coexist in a mutualistic relationship. Commensal bacteria play an active role in shaping and modulating physiological processes in the host, which include, but are not restricted to, the immune system and the intestinal barrier. Both play a crucial role in containing intestinal bacteria and other potentially noxious luminal antigens within the lumen and mucosal compartment. Although mutualism defines the relationship between the host and the intestinal microbiota, disruptions in this equilibrium may promote disease. Thus, alterations in gut microbiota (dysbiosis) have been linked to the recent increased expression of obesity, allergy, autoimmunity, functional and inflammatory disorders such as irritable bowel syndrome (IBS) and inflammatory bowel disease (IBD). In this article, we review the evidence supporting a role of gut microbiota in regulating intestinal barrier function. We discuss the hypothesis that microbial factors can modulate the barrier in ways that can prevent or promote gastrointestinal disease. A better understanding of the role of the intestinal microbiota in maintaining a functional intestinal barrier may help develop targeted strategies to prevent and treat disease.

  19. Regionalization of pIgR expression in the mucosa of mouse small intestine.

    PubMed

    Reséndiz-Albor, Aldo A; Reina-Garfias, Humberto; Rojas-Hernández, Saúl; Jarillo-Luna, Adriana; Rivera-Aguilar, Víctor; Miliar-García, Angel; Campos-Rodríguez, Rafael

    2010-01-18

    Few reports exist on the differences in cell populations or immunological functions between the proximal and distal segments of the small intestine (SI). In the current contribution we analyzed the expression of the polymeric immunoglobulin receptor (pIgR) and alpha chains as well as the density of IgA-producing cells from the proximal and distal intestinal segments from Balb/c mice. Furthermore, by using real-time RT-PCR we quantified the expression of cytokines (TNF-alpha, IFN-gamma, IL-4 and TGF-beta), Toll-like receptor-4 (TLR-4), and the glucocorticoid receptor (GR) involved in pIgR expression in intestinal epithelial cells (IEC). In this study, for the first time it has been demonstrated that the expression of the pIgR as well as alpha chain was greater in the proximal than the distal segment of the small intestine of normal mice. Moreover, we found striking differences in the expression of cytokines at the different intestinal compartments. Whereas the expression of TNF-alpha, IFN-gamma and TGF-beta was higher in lamina propria lymphocytes (LPL) of the distal than proximal segment, it was higher in IEC of the proximal than distal segment. In contrast, the expression of the gene for IL-4 was higher in the LPL of the proximal segment and the IEC of the distal segment. Although the overall expression of TNF-alpha, IL-4, IFN-gamma and TGF-beta was higher in the whole mucosa of the distal than proximal segment, we propose that cytokines produced by epithelial cells (TNF-alpha, IFN-gamma and TGF-beta) autocrinally up-regulate the expression of mRNA for the pIgR. Finally the expression of the GR was higher in the proximal segment, while the expression of the gene for TLR-4 was significantly higher in the IEC of the distal than proximal segment. The higher expression of pIgR found in the proximal segment is probably related to the effect on epithelial cells of the higher production of TNF-alpha, IFN-gamma and TGF-beta, as well as the higher expression of the

  20. Proteome analysis of the macroscopically affected colonic mucosa of Crohn’s disease and intestinal tuberculosis

    PubMed Central

    Rukmangadachar, Lokesh A.; Makharia, Govind K.; Mishra, Asha; Das, Prasenjit; Hariprasad, Gururao; Srinivasan, Alagiri; Gupta, Siddhartha Datta; Ahuja, Vineet; Acharya, Subrat K.

    2016-01-01

    Differentiation between intestinal tuberculosis (ITB) and Crohn’s disease (CD) is challenging in geographical regions where both these diseases are prevalent. There is a need of biomarkers for differentiation between these two disorders. Colonic biopsies from inflamed mucosa of treatment-naive patients with ITB, CD and controls were used for analysis. Protein extracted from biopsies was digested with trypsin and resulting peptides were labeled with iTRAQ reagents. The peptides were subsequently analyzed using LC-MS/MS for identification and quantification. Gene ontology annotation for proteins was analyzed in PANTHER. Validation experiments were done for six differentially expressed proteins using immunohistochemistry. 533 proteins were identified and 241 proteins were quantified from 5 sets of iTRAQ experiments. While 63 were differentially expressed in colonic mucosa of patients with CD and ITB in at least one set of iTRAQ experiment, 11 proteins were differentially expressed in more than one set of experiments. Six proteins used for validation using immunohistochemistry in a larger cohort of patients; none of them however was differentially expressed in patients with ITB and CD. There are differentially expressed proteins in tissue proteome of CD and ITB. Further experiments are required using a larger cohort of homogeneous tissue samples. PMID:26988818

  1. High-throughput sequencing reveals differing immune responses in the intestinal mucosa of two inbred lines afflicted with Necrotic enteritis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We investigated the necrotic enteritis (NE)-induced transcripts of immune-related genes in the intestinal mucosa of two highly inbred White Leghorn chicken lines, line 6.3 and line 7.2, which share the same MHC haplotype and show different levels of NE susceptibility using high-throughput RNA sequen...

  2. Intestinal barrier integrity and function in infants with cholestasis

    PubMed Central

    Sherif, Tahra M. K.; Mohammed, Omnia A.; Nasif, Khalid A.; El Gezawy, Ebtesam M.

    2017-01-01

    Background/Aims The safety of the human body is maintained by effective monitoring of the mucosal surface integrity and protection against potentially harmful compounds. This function of the gut called intestinal barrier function can be affected by cholestasis and the absence of bile in the intestinal lumen. We aimed to determine whether the gut barrier integrity is impaired in infants with cholestasis by evaluation of the intestinal fatty acid binding proteins (I-FABP) and ileal bile acid binding protein (I-BABP) as markers of intestinal epithelial cell damage and plasma D-lactate level as a marker of gut wall permeability. Methods This case-control study included 53 infants with cholestasis and 29 controls. Serum levels of I-FABP, I-BABP, and D-lactate were measured in all subjects. Results Both groups of patients with neonatal hepatitis and biliary atresia showed significantly higher levels of I-FABP and I-BABP than the controls. There were no differences in the serum D-lactate level between the cases and controls. There was no difference between the two groups of patients (I and II) regarding any of the parameters studied. No significant correlations between serum levels of I-FABP, I-BABP, or D-lactate and total or direct bilirubin levels were found in the cholestatic infants. Conclusions The intestinal epithelial barrier integrity is breached nearly in all parts of the intestine in infants with cholestasis. Further research is recommended to determine the impact of this finding on the management of these infants. The relationship between physical intestinal barrier damage and its functional failure remains subject for further research. PMID:28239322

  3. Host-microbial interactions and regulation of intestinal epithelial barrier function: From physiology to pathology

    PubMed Central

    Yu, Linda Chia-Hui; Wang, Jin-Town; Wei, Shu-Chen; Ni, Yen-Hsuan

    2012-01-01

    The gastrointestinal tract is the largest reservoir of commensal bacteria in the human body, providing nutrients and space for the survival of microbes while concurrently operating mucosal barriers to confine the microbial population. The epithelial cells linked by tight junctions not only physically separate the microbiota from the lamina propria, but also secrete proinflammatory cytokines and reactive oxygen species in response to pathogen invasion and metabolic stress and serve as a sentinel to the underlying immune cells. Accumulating evidence indicates that commensal bacteria are involved in various physiological functions in the gut and microbial imbalances (dysbiosis) may cause pathology. Commensal bacteria are involved in the regulation of intestinal epithelial cell turnover, promotion of epithelial restitution and reorganization of tight junctions, all of which are pivotal for fortifying barrier function. Recent studies indicate that aberrant bacterial lipopolysaccharide-mediated signaling in gut mucosa may be involved in the pathogenesis of chronic inflammation and carcinogenesis. Our perception of enteric commensals has now changed from one of opportunistic pathogens to active participants in maintaining intestinal homeostasis. This review attempts to explain the dynamic interaction between the intestinal epithelium and commensal bacteria in disease and health status. PMID:22368784

  4. Cytokine response in the intestinal mucosa of hamsters infected with Taenia solium.

    PubMed

    Avila, Guillermina; Aguilar, Laura; Romero-Valdovinos, Mirza; Garcia-Vazquez, Francisco; Flisser, Ana

    2008-12-01

    Taenia solium grows in experimentally infected hamsters. An inflammatory reaction in the intestinal mucosa surrounding the scolex of the worms is produced. We searched for mRNA of Th1 and Th2 cytokines by in situ hybridization in intestinal biopsies. Hamsters were infected with T. solium cysticerci and necropsied on different days post infection (d.p.i.). Tissue from the small intestine was taken from the area surrounding the tapeworm scolex, fixed, and processed for histology. Antisense probes for the detection of interferon (IFN)-gamma, interleukin (IL)-4, IL-5, and IL-13 were used. Kinetics of each cytokine was defined through detection on specific mRNA by counting the number of positive infected hamsters and of positive cells per 100 enterocytes on different d.p.i. IFN-gamma was detected as of d.p.i. 2; all animals were positive on d.p.i. 4 and 8; and on d.p.i. 16, only 20% were still positive. IL-13 had a pattern similar to IFN-gamma, but all hamsters remained positive until d.p.i. 16 when the experiment was terminated. IL-4 was positive in 40% of infected hamsters on d.p.i. 6. On d.p.i. 8, IL-5 was only detected in 20% but increased to 100% by d.p.i. 16. These data suggest that tapeworms induce a mixed Th1/Th2 response with a polarization toward Th2 at 2 weeks post infection, which may influence the expulsion of worms.

  5. Relationship between β-catenin expression and epithelial cell proliferation in gastric mucosa with intestinal metaplasia

    PubMed Central

    Romiti, Adriana; Zullo, Angelo; Borrini, Francesco; Sarcina, Ida; Hassan, Cesare; Winn, Simon; Tomao, Silverio; Vecchione, Aldo; Morini, Sergio; Mingazzini, Pietro

    2005-01-01

    AIM: To investigate β-catenin expression in patients with intestinal metaplasia, and to look for a possible relationship between β-catenin expression and either epithelial proliferation values or Helicobacter pylori (H pylori) infection. METHODS: Twenty patients with complete type intestinal metaplasia were studied. β-catenin expression and epithelial cell proliferation in antral mucosa were assessed using an immunohistochemical analysis. H pylori infection was detected by histology and a rapid urease test. RESULTS: Reduced β-catenin expression on the surface of metaplastic cells was detected in 13 (65%) out of 20 patients. Moreover, in eight (40%) patients intranuclear expression of β-catenin was found. When patients were analyzed according to H pylori infection, the prevalence of both β-catenin reduction at the cell surface and its intranuclear localization did not significantly differ between infected and uninfected patients. Cell proliferation was higher in patients with intranuclear β-catenin expression as compared to the remaining patients, although the difference failed to reach the statistical significance (36 ± 8.9 vs 27.2 ± 11.4, P = 0.06). On the contrary, a similar cell proliferation value was observed between patients with reduced expression of β-catenin on cell surface and those with a normal expression (28.1 ± 11.8 vs 26.1 ± 8.8, P = 0.7). H pylori infection significantly increased cell proliferation (33.3 ± 10.2% vs 24.6 ± 7.4%, respectively, P = 0.04). CONCLUSION: Both cell surface reduction and intranuclear accumulation of β-catenin were detected in intestinal metaplasia. The intranuclear localization of β-catenin increases cell proliferation. H pylori infection does not seem to play a direct role in β-catenin alterations, whilst it significantly increases cell proliferation. PMID:16038041

  6. Dietary grape seed proanthocyanidins (GSPs) improve weaned intestinal microbiota and mucosal barrier using a piglet model

    PubMed Central

    Han, Meng; Song, Peixia; Huang, Chang; Rezaei, Arash; Farrar, Shabnam; Brown, Michael A.; Ma, Xi

    2016-01-01

    Proanthocyanidins have been suggested as an effective antibiotic alternative, however their mechanisms are still unknown. The present study investigated the effects of grape seed proanthocyanidins on gut microbiota and mucosal barrier using a weaned piglet model in comparison with colistin. Piglets weaned at 28 day were randomly assigned to four groups treated with a control ration, or supplemented with 250 mg/kg proanthocyanidins, kitasamycin/colistin, or 250 mg/kg proanthocyanidins and half-dose antibiotics, respectively. On day 28, the gut chyme and tissue samples were collected to test intestinal microbiota and barrier function, respectively. Proanthocyanidins treated piglets had better growth performance and reduced diarrhea incidence (P < 0.05), accompanied with decreased intestinal permeability and improved mucosal morphology. Gene sequencing analysis of 16S rRNA revealed that dietary proanthocyanidins improved the microbial diversity in ileal and colonic digesta, and the most abundant OTUs belong to Firmicutes and Bacteroidetes spp. Proanthocyanidins treatment decreased the abundance of Lactobacillaceae, and increased the abundance of Clostridiaceae in both ileal and colonic lumen, which suggests that proanthocyanidins treatment changed the bacterial composition and distribution. Administration of proanthocyanidins increased the concentration of propionic acid and butyric acid in the ileum and colon, which may activate the expression of GPR41. In addition, dietary proanthocyanidins improved the antioxidant indices in serum and intestinal mucosa, accompanied with increasing expression of barrier occludin. Our findings indicated that proanthocyanidins with half-dose colistin was equivalent to the antibiotic treatment and assisted weaned animals in resisting intestinal oxidative stress by increasing diversity and improving balance of gut microbes. PMID:27880936

  7. Effects of simulated weightlessness on the intestinal mucosal barrier of rats

    NASA Astrophysics Data System (ADS)

    Chen, Ying; Yang, Chun-min; Mao, Gao-ping; Liu, Qing-sen; Guo, Ming-zhou

    2011-07-01

    This study employed a rat tail-suspension model to investigate the effects of simulated weightlessness on the intestinal mucosal barrier. Twenty-four Wistar rats were randomly divided into control (CON), 14-day tail-suspension (SUS-14d), and 21-day tail-suspension (SUS-21d) groups ( n = 8 per group). Expression of occludin and zonula occludins-1 (ZO-1), proteins of the tight junction (TJ), in the intestinal mucosa was measured by immunohistochemical analysis, Western blotting, and mRNA fluorescent quantitation PCR. Plasma concentrations of diamine oxidase (DAO) and D-lactate were determined using an enzymatic spectrophotometric assay. Expression of occludin and ZO-1 was reduced in the SUS-14d and SUS-21d groups as compared to the CON group, with lowest expression observed in the SUS-21d group ( P < 0.01). Examination by transmission electron microscopy (TEM) of the jejunal epithelium revealed increased intercellular space, decreased TJ and desmosome densities, and destruction of microvilli in the SUS-14d and SUS-21d groups. Plasma DAO and D-lactate concentrations in the SUS-21d group were higher than those in SUS-14d group and significantly higher than those in the CON group ( P < 0.01). In all three groups, the expression of occludin and ZO-1 was found to correlate negatively with DAO ( P < 0.01) and D-lactate ( P < 0.01) concentrations. It is concluded that simulated weightless results in down-regulation of expression of TJ proteins in the rat intestinal mucosa. Simulated weightlessness is proposed to increase intestinal permeability through damage to the TJ.

  8. The effects of natural and modified clinoptilolite on intestinal barrier function and immune response to LPS in broiler chickens.

    PubMed

    Wu, Qiu Jue; Zhou, Yan Min; Wu, Ya Nan; Zhang, Li Li; Wang, Tian

    2013-05-15

    The protection of intestinal barrier function and the anti-inflammatory effects of natural clinoptilolite (NCLI) and modified clinoptilolite (MCLI) were investigated in broilers that were repeatedly challenged with lipopolysaccharide (LPS). A total of 288 1-d-old broiler chicks were divided equally into three treatment groups: control, NCLI-treated (2%) and MCLI-treated (2%). Half of the birds from each treatment group were challenged with 0.9% NaCl solution or LPS (250μg/kg body weight, administered orally) at 16, 18 and 21d of age. The results indicated that, prior to LPS challenge, the diet had no effect on bird growth performance (P>0.05). The oral administration of LPS was also not associated with any significant changes in poultry performance (P>0.05). In LPS-challenged birds that were pretreated with NCLI (2%) or MCLI (2%), the LPS-induced increases in the plasma and intestinal mucosa concentrations of TNF-α, IL-1β, IL-2, IL-6, IL-4 and IL-10 were dramatically attenuated. Additionally, significant decreases in the plasma d-lactic acid and diamine oxidase (DAO) levels were found in birds that were pretreated with NCLI or MCLI. Furthermore, both NCLI and MCLI reduced the sICAM-1 concentration in the intestinal mucosa. In conclusion, NCLI and MCLI are able to prevent the LPS-induced intestinal mucosa damage and inflammatory response in vivo. These beneficial effects suggest that NCLI and MCLI act as anti-inflammatory agents in part by inhibiting neutrophil infiltration and hyperactivation and by suppressing the secretion of various plasma and intestinal mucosa inflammatory mediators.

  9. Activation of Immune and Defense Responses in the Intestinal Mucosa by Outer Membrane Vesicles of Commensal and Probiotic Escherichia coli Strains

    PubMed Central

    Fábrega, María José; Aguilera, Laura; Giménez, Rosa; Varela, Encarna; Alexandra Cañas, María; Antolín, María; Badía, Josefa

    2016-01-01

    The influence of microbiota in human health is well-known. Imbalances in microbiome structure have been linked to several diseases. Modulation of microbiota composition through probiotic therapy is an attempt to harness the beneficial effects of commensal microbiota. Although, there is wide knowledge of the responses induced by gut microbiota, the microbial factors that mediate these effects are not well-known. Gram-negative bacteria release outer membrane vesicles (OMVs) as a secretion mechanism of microbial factors, which have an important role in intercellular communication. Here, we investigated whether OMVs from the probiotic Escherichia coli strain Nissle 1917 (EcN) or the commensal E. coli strain ECOR12 trigger immune responses in various cellular models: (i) peripheral blood mononuclear cells (PBMCs) as a model of intestinal barrier disruption, (ii) apical stimulation of Caco-2/PMBCs co-culture as a model of intact intestinal mucosa, and (iii) colonic mucosa explants as an ex vivo model. Stimulations with bacterial lysates were also performed. Whereas, both OMVs and lysates activated expression and secretion of several cytokines and chemokines in PBMCs, only OMVs induced basolateral secretion and mRNA upregulation of these mediators in the co-culture model. We provide evidence that OMVs are internalized in polarized Caco-2 cells. The activated epithelial cells elicit a response in the underlying immunocompetent cells. The OMVs effects were corroborated in the ex vivo model. This experimental study shows that OMVs are an effective strategy used by beneficial gut bacteria to communicate with and modulate host responses, activating signaling events through the intestinal epithelial barrier. PMID:27242727

  10. Cordyceps sinensis preserves intestinal mucosal barrier and may be an adjunct therapy in endotoxin-induced sepsis rat model: a pilot study

    PubMed Central

    Gu, Guo-Sheng; Ren, Jian-An; Li, Guan-Wei; Yuan, Yu-Jie; Li, Ning; Li, Jie-Shou

    2015-01-01

    Background: Cordyceps sinensis (C. sinensis), a traditional Chinese medicine, exhibits various pharmacological activities such as reparative, antioxidant, and apoptosis inhibitory effects. Intestinal barrier dysfunction plays a vital role in the progression of sepsis. We aimed to explore the effect of C. sinensis on the gut barrier and evaluate its efficacy in sepsis. Methods: A murine model of gut barrier dysfunction was created by intraperitoneal injection of endotoxin. C. sinensis or saline was administered orally after the induction of sepsis. Alterations of intestinal barrier were evaluated and compared in terms of epithelial cell apoptosis, proliferation index (PI), intercellular tight junction (TJ) and proliferating cell nuclear antigen (PCNA). Results: C. sinensis significantly decreased the percentage of apoptotic cells and promoted mucosal cells proliferation indicated by enhanced PI and PCNA expression in the intestinal mucosa compared to control group. The TJs between epithelial cells which were disrupted in septic rats were also restored by treatment of C. sinensis. In survival studies, C. sinensis was demonstrated to confer a protection against the lethal effect of sepsis. Conclusion: These results suggest that C. sinensis has gut barrier-protection effect in endotoxin-induced sepsis by promoting the proliferation and inhibiting the apoptosis of intestinal mucosal cells, as well as restoring the TJs of intestinal mucosa. C. sinensis may have the potential to be a useful adjunct therapy for sepsis. PMID:26221273

  11. Morphological characteristics of the intestinal mucosa in the Afghan pika (Ochotona rufescens rufescens).

    PubMed

    Kurohmaru, M; Hayakawa, T; Seki, M; Zyo, K

    1984-10-01

    The intestinal mucosa of the pika was examined with the naked eyes, a light microscope and a scanning electron microscope and was compared with that of the rabbit. The duodenal mucosa of the rabbit showed wavy folds different from so-called villi, while that of the pika exhibited leaf-like or columnar villi. In addition to the specific ileocecal lymphoid apparatuses, the pika had the peculiar region between the cecum and the proximal colon. That region called "the constricted portion" possessed characteristic net-arranged folds and well-developed muscular layers. At the lateral surface of these folds, small villus-like protrusions projected into the lumen in large numbers. The spiral fold ran around the mucosal surface of the rabbit cecum, whereas numerous slender protrusions, cecal digitations, projected into the lumen of the pika cecum. Although the colon of the pika showed a similar external figure to that of the rabbit, some differences were obviously found in histological structures. The first segment of the pika proximal colon with three teniae possessed several protrusions and well-developed mucous glands, while that of the rabbit had neither protrusions nor mucous glands. The second segment of the pika proximal colon with one tenia was covered with numerous villus-like protrusions, while that of the rabbit was composed of wart-like protrusions. The tubular mucous glands were observed in the lamina propria of the pika as well as the rabbit. The distal colon of the pika showed a flat mucosal surface and possessed tubular mucous glands as observed in the rabbit.

  12. Myenteric neurons and intestinal mucosa of diabetic rats after ascorbic acid supplementation

    PubMed Central

    de Freitas, Priscila; Natali, Maria Raquel Marçal; Pereira, Renata Virginia Fernandes; Neto, Marcilio Hubner Miranda; Zanoni, Jacqueline Nelisis

    2008-01-01

    AIM: To investigate the effect of ascorbic acid (AA) dietary supplementation on myenteric neurons and epithelial cell proliferation of the jejunum of adult rats with chronic diabetes mellitus. METHODS: Thirty rats at 90 d of age were divided into three groups: Non-diabetic, diabetic and diabetic treated with AA (DA) (1 g/L). After 120 d of treatment with AA the animals were killed. The myenteric neurons were stained for myosin-V and analyzed quantitatively in an area of 11.2 mm2/animal. We further measured the cellular area of 500 neurons per group. We also determined the metaphasic index (MI) of the jejunum mucosa layer of about 2500 cells in the intestinal crypts, as well as the dimensions of 30 villi and 30 crypts/animal. The data area was analyzed using the Olympus BX40 microscope. RESULTS: There was an increase of 14% in the neuronal density (792.6 ± 46.52 vs 680.6 ± 30.27) and 4.4% in the cellular area (303.4 ± 5.19 vs 291.1 ± 6.0) respectively of the diabetic group treated with AA when compared to control diabetic animals. There were no significant differences in MI parameters, villi height or crypt depths among the groups. CONCLUSION: Supplementation with AA in the diabetic animal promoted moderate neuroprotection. There was no observation of alteration of the cellular proliferation of the jejunum mucosa layer of rats with chronic diabetes mellitus with or without supplementation with AA. PMID:19030205

  13. Effects of soybean agglutinin on intestinal barrier permeability and tight junction protein expression in weaned piglets.

    PubMed

    Zhao, Yuan; Qin, Guixin; Sun, Zewei; Che, Dongsheng; Bao, Nan; Zhang, Xiaodong

    2011-01-01

    This study was developed to provide further information on the intestinal barrier permeability and the tight junction protein expression in weaned piglets fed with different levels of soybean agglutinin (SBA). Twenty-five weaned crossbred barrows (Duroc × Landrace × Yorkshire) were selected and randomly allotted to five groups, each group with five replicates. The piglets in the control group were not fed with leguminous products. 0.05, 0.1, 0.15 and 0.2% SBA was added to the control diet to form four experimental diets, respectively. After the experimental period of 7 days (for each group), all the piglets were anesthetized with excess procaine and slaughtered. The d-lactic acid in plasma and the Ileal mucosa diamine oxidase (DAO) was analyzed to observe the change in the intestinal permeability. The tight junction proteins occludin and ZO-1 in the jejunum tissue distribution and relative expression were detected by immunohistochemistry and Western Blot. The results illustrated that a high dose of SBA (0.1-0.2%) could increase the intestinal permeability and reduce piglet intestinal epithelial tight junction protein occludin or ZO-1 expression, while low dose of SBA (0.05% of total diet) had no significant affects. The contents of DAO, d-lactic acid, occludin or ZO-1, had a linear relationship with the SBA levels (0-0.2%) in diets. The high dose SBA (0.1-0.2%) could increase the intestinal permeability and reduce piglet intestinal epithelial tight junction protein occludin or ZO-1 expression, while low dose of SBA (0.05% of total diet) had no affects.

  14. Epigenetic control of intestinal barrier function and inflammation in zebrafish

    PubMed Central

    Marjoram, Lindsay; Alvers, Ashley; Deerhake, M. Elizabeth; Bagwell, Jennifer; Mankiewicz, Jamie; Cocchiaro, Jordan L.; Beerman, Rebecca W.; Willer, Jason; Sumigray, Kaelyn D.; Katsanis, Nicholas; Rawls, John F.; Goll, Mary G.; Bagnat, Michel

    2015-01-01

    The intestinal epithelium forms a barrier protecting the organism from microbes and other proinflammatory stimuli. The integrity of this barrier and the proper response to infection requires precise regulation of powerful immune homing signals such as tumor necrosis factor (TNF). Dysregulation of TNF leads to inflammatory bowel diseases (IBD), but the mechanism controlling the expression of this potent cytokine and the events that trigger the onset of chronic inflammation are unknown. Here, we show that loss of function of the epigenetic regulator ubiquitin-like protein containing PHD and RING finger domains 1 (uhrf1) in zebrafish leads to a reduction in tnfa promoter methylation and the induction of tnfa expression in intestinal epithelial cells (IECs). The increase in IEC tnfa levels is microbe-dependent and results in IEC shedding and apoptosis, immune cell recruitment, and barrier dysfunction, consistent with chronic inflammation. Importantly, tnfa knockdown in uhrf1 mutants restores IEC morphology, reduces cell shedding, and improves barrier function. We propose that loss of epigenetic repression and TNF induction in the intestinal epithelium can lead to IBD onset. PMID:25730872

  15. Mechanism of intestinal mucosal barrier dysfunction in a rat model of chronic obstructive pulmonary disease: An observational study

    PubMed Central

    Xin, Xiaofeng; Dai, Wei; Wu, Jie; Fang, Liping; Zhao, Ming; Zhang, Pengpeng; Chen, Min

    2016-01-01

    The aim of the present study was to investigate intestinal mucosal barrier dysfunction in a rat model of chronic obstructive pulmonary disease (COPD). Male Sprague Dawley rats (n=40) were evenly randomized into control and COPD groups and the COPD model was established by regulated exposure to cigarette smoke for 6 months. Histopathological changes of the lung and intestinal tissues were detected by hematoxylin and eosin staining. Expression of the tight junction proteins occludin and zona occludens-1 (ZO-1) in the intestinal tissues were analyzed by western blotting, serum diamine oxidase (DAO) activity was detected by spectrophotometry, the urinary lactulose to mannitol ratio (L/M) was evaluated by high performance liquid chromatography, and intestinal tissue secretion of tumor necrosis factor (TNF)-α, interferon (IFN)-γ and interleukin (IL)-8 were detected by ELISA. Lung histopathology revealed thinned alveolar walls, ruptured alveolar septa, enlarged and deformed alveoli, and the formation of bullae and emphysema due to alveolar fusion in the COPD group, while intestinal histopathology indicated clearly swollen intestines with darkened and gray mucosa, neutrophil infiltration of the intestinal mucosal and regional epithelial shedding. The occludin and ZO-1 expression levels were significantly lower in the COPD group compared with those in the corresponding control group (P<0.05), while the urinary L/M ratio was significantly higher (P<0.05). Furthermore, the serum DAO activity and secretion of TNF-α, IFN-γ and IL-8 in the intestinal tissues were significantly higher in the COPD group than in the control group (each P<0.05). Dysfunctional and structural changes were observed in the intestinal mucosal barrier in COPD model rats, which may be associated with the increased intestinal inflammatory responses. PMID:27588054

  16. Protective Effect of Huoxiang Zhengqi Oral Liquid on Intestinal Mucosal Mechanical Barrier of Rats with Postinfectious Irritable Bowel Syndrome Induced by Acetic Acid

    PubMed Central

    Liu, Yao; Liu, Wei; Peng, Qiu-Xian; Peng, Jiang-Li; Yu, Lin-Zhong; Hu, Jian-Lan

    2014-01-01

    In this study, a rat model with acetic acid-induced PI-IBS was used to study the role of HXZQ oral liquid in repairing the colonic epithelial barrier and reducing intestinal permeability. Pathomorphism of colonic tissue, epithelial ultrastructure, DAO activity in serum, and the protein expression of ZO-1 and occludin were examined to investigate protective effect mechanisms of HXZQ on intestinal mucosa barrier and then present experimental support for its use for prevention and cure of PI-IBS. PMID:25254052

  17. The epithelial barrier is maintained by in vivo tight junction expansion during pathologic intestinal epithelial shedding

    PubMed Central

    Marchiando, Amanda M.; Shen, Le; Graham, W. Vallen; Edelblum, Karen L.; Duckworth, Carrie A.; Guan, Yanfang; Montrose, Marshall H.; Turner, Jerrold R.; Watson, Alastair J.M.

    2011-01-01

    BACKGROUND & AIMS Tumor necrosis factor (TNF) increases intestinal epithelial cell shedding and apoptosis, potentially challenging the barrier between the gastrointestinal lumen and internal tissues. We investigated the mechanism of tight junction remodeling and barrier maintenance, as well as the roles of cytoskeletal regulatory molecules during TNF-induced shedding. METHODS We studied wild-type and transgenic mice that express the fluorescent-tagged proteins enhanced green fluorescent protein–occludin or monomeric red fluorescent protein1–ZO-1. After injection of high doses of TNF (7.5µg, i.p.), laparotomies were performed and segments of small intestine were opened to visualize the mucosa by video confocal microscopy. Pharmacologic inhibitors and knockout mice were used to determine the roles of caspase activation, actomyosin, and microtubule remodeling and membrane trafficking in epithelial shedding. RESULTS Changes detected included redistribution of the tight junction proteins ZO-1 and occluding to lateral membranes of shedding cells. These proteins ultimately formed a funnel around the shedding cell that defined the site of barrier preservation. Claudins, E-cadherin, F-actin, myosin II, Rho-associated kinase (ROCK), and myosin light chain kinase (MLCK) were also recruited to lateral membranes. Caspase activity, myosin motor activity, and microtubules were required to initiate shedding, whereas completion of the process required microfilament remodeling and ROCK, MLCK, and dynamin II activities. CONCLUSIONS Maintenance of the epithelial barrier during TNF-induced cell shedding is a complex process that involves integration of microtubules, microfilaments, and membrane traffic to remove apoptotic cells. This process is accompanied by redistribution of apical junctional complex proteins to form intercellular barriers between lateral membranes and maintain mucosal function. PMID:21237166

  18. Enteral feeding and its impact on the gut immune system and intestinal mucosal barrier

    PubMed Central

    Kruszewski, Wiesław J.; Buczek, Tomasz

    2015-01-01

    Enteral feeding is the preferred method of nutritional therapy. Mucosal lack of contact with nutrients leads do lymphoid tissue atrophy, immune system functional decline, and intensification in bacterial translocation. Currently, it is assumed that microbiome is one of the body organs that has a significant impact on health. The composition of microbiome is not affected by age, sex, or place of residence, although it changes rapidly after diet modification. The composition of the microbiome is determined by enterotype, which is specific for each organism. It has a significant impact on the risk of diabetes, cancer, atherosclerosis, and other diseases. This review gathers data on interaction between gut-associated lymphoid tissue, mucosa-associated lymphoid tissue, microbiome, and the intestinal mucosal barrier. Usually, the information on the aforementioned is scattered in specialist-subject magazines such as gastroenterology, microbiology, genetics, biochemistry, and others. PMID:26557936

  19. Self assembled hyaluronic acid nanoparticles as a potential carrier for targeting the inflamed intestinal mucosa.

    PubMed

    Vafaei, Seyed Yaser; Esmaeili, Motahareh; Amini, Mohsen; Atyabi, Fatemeh; Ostad, Seyed Naser; Dinarvand, Rassoul

    2016-06-25

    To develop a nanoparticulate drug carrier for targeting of the inflamed intestinal mucosa, amphiphilic hyaluronic acid (HA) conjugates were synthesized, which could form self-assembled nanoparticles (NPs) in aqueous solution and budesonide (BDS) was loaded into the HANPs. Their particle sizes were in the range of 177 to 293nm with negative surface charge. The model of inflammatory CACO-2 cells was utilized to investigate the therapeutic potential of budesonide loaded HA nanocarriers. The highest expression of CD44 receptors was found on inflamed Caco-2 cells, as determined by flow cytometry. FITC-labeled HANPs revealed greater uptake in inflamed CACO-2 cells compared to untreated CACO-2 and CD44-negative cell lines, NIH3T3. BDS loaded HANPs displayed almost no toxicity indicating HANPs are excellent biocompatible nano-carriers. BDS loaded HANPs demonstrated higher anti-inflammatory effect on IL-8 and TNF-α secretion in inflamed cell model compared to the same dose of free drug. These results revealed the promising potential of HA nanoparticles as a targeted drug delivery system for IBD treatment.

  20. Factors influencing pyrroline 5-carboxylate synthesis from glutamate by rat intestinal mucosa mitochondria

    SciTech Connect

    Henslee, J.G.; Wakabayashi, Y.; Small, C.; Jones, M.E.

    1983-10-15

    Factors influencing pyrroline 5-carboxylate (P5C) synthesis from glutamate by a subcellular fraction enriched in mitochondria of rat small intestinal mucosa have been studied. P5C synthesis decreased rapidly if this subcellular fraction was preincubated at 20 degrees C in the absence of substrates; this effect suggests that the enzyme(s) catalyzing P5C synthesis from glutamate (P5C synthase) is unstable in the absence of substrates. In the presence of substrates P5C synthesis increased linearly for the first 30 min of incubation, suggesting that the substrates promote enzyme stability. Pyridoxal 5'-phosphate is an effective inhibitor of P5C synthase whereas pyridoxamine 5'-phosphate and pyridoxal are not inhibitory. Potassium phosphate, KCl, and KBr each inhibited P5C synthase but potassium-Hepes (4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid) did not. Potassium phosphate was the most potent inhibitor followed by KBr, and then KCl. These results suggest P5C synthase is sensitive to anion inhibition. Both L-ornithine and D-ornithine inhibited P5C synthase; L-proline did not inhibit. Several analogs of ornithine and proline were also tested and none was found to inhibit P5C synthase; the inhibition by ornithine is, therefore, rather specific and it may prove to contribute to the regulation of metabolism of these amino acids.

  1. Central Role of the Gut Epithelial Barrier in the Pathogenesis of Chronic Intestinal Inflammation: Lessons Learned from Animal Models and Human Genetics

    PubMed Central

    Pastorelli, Luca; De Salvo, Carlo; Mercado, Joseph R.; Vecchi, Maurizio; Pizarro, Theresa T.

    2013-01-01

    The gut mucosa is constantly challenged by a bombardment of foreign antigens and environmental microorganisms. As such, the precise regulation of the intestinal barrier allows the maintenance of mucosal immune homeostasis and prevents the onset of uncontrolled inflammation. In support of this concept, emerging evidence points to defects in components of the epithelial barrier as etiologic factors in the pathogenesis of inflammatory bowel diseases (IBDs). In fact, the integrity of the intestinal barrier relies on different elements, including robust innate immune responses, epithelial paracellular permeability, epithelial cell integrity, as well as the production of mucus. The purpose of this review is to systematically evaluate how alterations in the aforementioned epithelial components can lead to the disruption of intestinal immune homeostasis, and subsequent inflammation. In this regard, the wealth of data from mouse models of intestinal inflammation and human genetics are pivotal in understanding pathogenic pathways, for example, that are initiated from the specific loss of function of a single protein leading to the onset of intestinal disease. On the other hand, several recently proposed therapeutic approaches to treat human IBD are targeted at enhancing different elements of gut barrier function, further supporting a primary role of the epithelium in the pathogenesis of chronic intestinal inflammation and emphasizing the importance of maintaining a healthy and effective intestinal barrier. PMID:24062746

  2. Postinjury Vagal Nerve Stimulation Protects Against Intestinal Epithelial Barrier Breakdown

    PubMed Central

    Krzyzaniak, Michael; Peterson, Carrie; Loomis, William; Hageny, Ann-Marie; Wolf, Paul; Reys, Luiz; Putnam, James; Eliceiri, Brian; Baird, Andrew; Bansal, Vishal; Coimbra, Raul

    2014-01-01

    Background Vagal nerve stimulation (VNS) can have a marked anti-inflammatory effect. We have previously shown that preinjury VNS prevented intestinal barrier breakdown and preserved epithelial tight junction protein expression. However, a pretreatment model has little clinical relevance for the care of the trauma patient. Therefore, we postulated that VNS conducted postinjury would also have a similar protective effect on maintaining gut epithelial barrier integrity. Methods Male balb/c mice were subjected to a 30% total body surface area, full-thickness steam burn followed by right cervical VNS at 15, 30, 60, 90, 120, and 150 minutes postinjury. Intestinal barrier dysfunction was quantified by permeability to 4 kDa fluorescein isothiocyanate-Dextran, histologic evaluation, gut tumor necrosis factor-alpha (TNF-α) enzyme-linked immunosorbent assay, and expression of tight junction proteins (myosin light chain kinase, occludin, and ZO-1) using immunoblot and immunoflourescence. Results Histologic examination documented intestinal villi appearance similar to sham if cervical VNS was performed within 90 minutes of burn insult. VNS done after injury decreased intestinal permeability to fluorescein isothiocyanate-Dextran when VNS was ≤90 minutes after injury. Burn injury caused a marked increase in intestinal TNF-α levels. VNS-treated animals had TNF-α levels similar to sham when VNS was performed within 90 minutes of injury. Tight junction protein expression was maintained at near sham values if VNS was performed within 90 minutes of burn, whereas expression was significantly altered in burn. Conclusion Postinjury VNS prevents gut epithelial breakdown when performed within 90 minutes of thermal injury. This could represent a therapeutic window and clinically relevant strategy to prevent systemic inflammatory response distant organ injury after trauma. PMID:21610431

  3. Antibiotics conspicuously affect community profiles and richness, but not the density of bacterial cells associated with mucosa in the large and small intestines of mice.

    PubMed

    Puhl, Nathan J; Uwiera, Richard R E; Yanke, L Jay; Selinger, L Brent; Inglis, G Douglas

    2012-02-01

    The influence of three antibiotics (bacitracin, enrofloxacin, and neomycin sulfate) on the mucosa-associated enteric microbiota and the intestines of mice was examined. Antibiotics caused conspicuous enlargement of ceca and an increase in overall length of the intestine. However, there were no pathologic changes associated with increased cecal size or length of the intestine. Conspicuous reductions in the richness of mucosa-associated bacteria and changes to community profiles within the small (duodenum, proximal jejunum, middle jejunum, distal jejunum, and ileum) and large (cecum, ascending colon, and descending colon) intestine occurred in mice administered antibiotics. Communities in antibiotic-treated mice were dominated by a limited number of Clostridium-like (i.e. clostridial cluster XIVa) and Bacteroides species. The richness of mucosa-associated communities within the small and large intestine increased during the 14-day recovery period. However, community profiles within the large intestine did not return to baseline (i.e. relative to the control). Although antibiotic administration greatly reduced bacterial richness, densities of mucosa-associated bacteria were not reduced correspondingly. These data showed that the antibiotics, bacitracin, enrofloxacin, and neomycin sulfate, administered for 21 days to mice did not sterilize the intestine, but did impart a tremendous and prolonged impact on mucosa-associated bacterial communities throughout the small and large intestine.

  4. A carvacrol-thymol blend decreased intestinal oxidative stress and influenced selected microbes without changing the messenger RNA levels of tight junction proteins in jejunal mucosa of weaning piglets.

    PubMed

    Wei, H-K; Xue, H-X; Zhou, Z X; Peng, J

    2017-02-01

    Recent studies indicate that intestinal oxidative stress and microbiota imbalance is involved in weaning-induced intestinal dysfunction in piglets. We have investigated the effect of feeding a carvacrol-thymol blend supplemented diet on intestinal redox status, selected microbial populations and the intestinal barrier in weaning piglets. The piglets (weaned at 21 days of age) were randomly allocated to two groups with six pens per treatment and 10 piglets per pen. At weaning day (21 days of age), six piglets were sacrificed before weaning to serve as the preweaning group. The weaned group was fed with a basal diet, while the weaned-CB group was fed with the basal diet supplemented with 100 mg/kg carvacrol-thymol (1 : 1) blend for 14 days. On day 7 post-weaning, six piglets from each group were sacrificed to determine intestinal redox status, selected microbial populations, messenger RNA (mRNA) transcript levels of proinflammatory cytokines and biomarkers of intestinal barrier function. Weaning resulted in intestinal oxidative stress, indicated by the increased concentration of reactive oxygen species and thiobarbituric acid-reactive substances present in the intestine. Weaning also reduced the population of Lactobacillus genus and increased the populations of Enterococcus genus and Escherichia coli in the jejunum, and increased mRNA levels of tumor necrosis factor α (TNF-α), interleukin 1β and interleukin 6 (IL-6). In addition, decreased mRNA levels of zonula occludens and occludin in the jejunal mucosa and increased plasma diamine oxidase concentrations indicated that weaning induced dysfunction of the intestinal barrier. On day 7 post-weaning, supplementation with the carvacrol-thymol blend restored weaning-induced intestinal oxidative stress. Compared with the weaned group, the weaned-CB group had an increased population of Lactobacillus genus but reduced populations of Enterococcus genus and E. coli in the jejunum and decreased mRNA levels of TNF-α. The

  5. Effects of ε-viniferin, a dehydrodimer of resveratrol, on transepithelial active ion transport and ion permeability in the rat small and large intestinal mucosa.

    PubMed

    Karaki, Shin-Ichiro; Ishikawa, Junji; Tomizawa, Yuka; Kuwahara, Atsukazu

    2016-05-01

    ε-Viniferin is a dehydrodimer of resveratrol, a polyphenol synthesized in many plants, including grapevine. The present study investigated the effects of ε-viniferin and resveratrol on epithelial secretory and barrier functions in isolated rat small and large intestinal mucosa. Mucosa-submucosa tissue preparations of various segments of the rat large and small intestines were mounted on Ussing chambers, and short-circuit current (Isc) and tissue conductance (Gt) were continuously measured. The mucosal addition of ε-viniferin (>10(-5) mol/L) and resveratrol (>10(-4) mol/L) to the cecal mucosa, which was the most sensitive region, induced an increase in Isc and a rapid phase decrease (P-1) followed by rapid (P-2) and broad (P-3) peak increases in Gt in concentration-dependent manners. Mucosal ε-viniferin (10(-4) mol/L), but not resveratrol (10(-4) mol/L), increased the permeability of FITC-conjugated dextran (4 kDa). The mucosal ε-viniferin-evoked changes in Isc (Cl(-) secretion), but not in Gt, were attenuated by a selective cyclooxygenase (COX)-1 inhibitor and a selective EP4 prostaglandin receptor. The mucosal ε-viniferin-evoked increase in Isc was partially attenuated, and P-2, but not P-1 or P-3, change in Gt was abolished by a transient receptor potential cation channel, subfamily A, member 1 (TRPA1) inhibitor. Moreover, the mucosal ε-viniferin concentration-dependently attenuated the mucosal propionate (1 mmol/L)-evoked increases in Isc and Gt Immunohistochemical studies revealed COX-1-immunoreactive epithelial cells in the cecal crypt. The present study showed that mucosal ε-viniferin modulated transepithelial ion transport and permeability, possibly by activating sensory epithelial cells expressing COX-1 and TRPA1. Moreover, mucosal ε-viniferin decreased mucosal sensitivity to other luminal molecules such as short-chain fatty acids. In conclusion, these results suggest that ε-viniferin modifies intestinal mucosal transport and barrier

  6. Effects of titanium dioxide nanoparticles on small intestinal mucosa in rats.

    PubMed

    Onishchenko, G E; Erokhina, M V; Abramchuk, S S; Shaitan, K V; Raspopov, R V; Smirnova, V V; Vasilevskaya, L S; Gmoshinski, I V; Kirpichnikov, M P; Tutelyan, V A

    2012-12-01

    Penetration of titanium dioxide nanoparticles into enterocytes after their administration into isolated loop of rat small intestine was shown in vivo by transmission electron microscopy. Using electron diffraction, titanium dioxide nanoparticles were identified in the apical regions of the cells under plasma membranes and in deeper parts of the cytoplasm as solitary objects or small aggregations. Water dispersions of nanoparticles (3-h exposure to high concentrations) caused no appreciable morphological changes in enterocyte ultrastructure. A 28-day subacute intragastric administration of water dispersion of nanoparticles to rats led to titanium accumulation in the liver, their level was significantly higher than in the control group, which was shown by mass spectrometry with inductive-bound plasma. These data indicated the possibility of penetration of titanium dioxide nanoparticles through the gastrointestinal barrier under near-physiological conditions.

  7. Yersinia pseudotuberculosis disrupts intestinal barrier integrity through hematopoietic TLR-2 signaling

    PubMed Central

    Jung, Camille; Meinzer, Ulrich; Montcuquet, Nicolas; Thachil, Elodie; Château, Danielle; Thiébaut, Raphaële; Roy, Maryline; Alnabhani, Ziad; Berrebi, Dominique; Dussaillant, Monique; Pedruzzi, Eric; Thenet, Sophie; Cerf-Bensussan, Nadine; Hugot, Jean-Pierre; Barreau, Frederick

    2012-01-01

    Intestinal barrier function requires intricate cooperation between intestinal epithelial cells and immune cells. Enteropathogens are able to invade the intestinal lymphoid tissue known as Peyer’s patches (PPs) and disrupt the integrity of the intestinal barrier. However, the underlying molecular mechanisms of this process are poorly understood. In mice infected with Yersinia pseudotuberculosis, we found that PP barrier dysfunction is dependent on the Yersinia virulence plasmid and the expression of TLR-2 by hematopoietic cells, but not by intestinal epithelial cells. Upon TLR-2 stimulation, Y. pseudotuberculosis–infected monocytes activated caspase-1 and produced IL-1β. In turn, IL-1β increased NF-κB and myosin light chain kinase activation in intestinal epithelial cells, thus disrupting the intestinal barrier by opening the tight junctions. Therefore, Y. pseudotuberculosis subverts intestinal barrier function by altering the interplay between immune and epithelial cells during infection. PMID:22565313

  8. The dynamic structure of a flat small intestinal mucosa studied on the explanted rat jejunum.

    PubMed

    Loehry, C A; Grace, R

    1974-04-01

    Small pieces of jejunum with an intact blood supply were explanted to the anterior abdominal wall in rats. Six weeks after explantation the mucosa appeared totally flat in many areas, both histologically and under the dissecting microscope. The structure of the flattened mucosa was shown to be identical to that in coeliac disease with hypertrophied intervillous ridges. A dynamic study with tritium-labelled thymidine demonstrated a considerably increased turnover in the flat mucosa with some disorganization of cell production and migration.

  9. Automated measurement of intestinal mucosa electrical parameters using a new digital clamp.

    PubMed

    Mathieu, Julien; Mammar, Saïd; Eto, Bruno

    2008-10-01

    Electrophysiological studies that include measurements of the electrical parameters of the epithelium offer insight into the cell's ability to react to different biological effectors and their functional viability. These parameters are commonly measured using a Ussing permeation chamber; however, most Ussing permeation chambers currently available must follow a strict operational protocol, and the type of electrodes used has to be taken into special consideration. The purpose of this study was to develop a new Ussing permeation chamber device with an automatic digital clamp which uses a microcontroller. Conventional electrodes, such as platinum or Ag/AgCl electrodes, are replaced by stainless steel 316L working electrodes. The electrode-electrolyte interface (inox-Ringer's) study was performed by impedance spectroscopy in the range of 1-10 kHz. The determination of Warburg's model electrical parameters was inferred from the Nyquist diagram. The model validation of the new digital clamp was performed experimentally on isolated segments of mouse jejunum. Two main study results should be mentioned. One is that impedance spectroscopy on stainless steel electrodes has provided Warburg's parameters, allowing the development of a transfer function model. The other is that the new digital clamp can simultaneously measure or calculate conductance, potential difference and short-circuit current. These results have also confirmed the great importance of Warburg's model for determining the electrical parameters of the electrode-electrolyte interface, and have shown that the measurement of intestinal mucosa electrical parameters can be achieved with a digital correction. Finally, the results suggest that stainless steel electrodes can be used successfully in a Ussing permeation chamber as working electrodes.

  10. Nano-hydroxyapatite-thermally denatured small intestine sub-mucosa composites for entheses applications.

    PubMed

    Perla, Venu; Webster, Thomas J

    2006-01-01

    The objective of the present in vitro study was to estimate the adhesion strength of nanometer crystalline hydroxyapatite (HA)-small intestine sub-mucosa (SIS) composites on model implant surfaces. Techniques of thermal denaturation (60 degrees C, 20 min) of SIS were used to enhance the adhesion strength of entheses materials to underlying implants. Specifically, results indicated that the adhesion strength of thermally denatured SIS was 2-3 times higher than that for normal unheated SIS. In addition, aqua-sonicated, hydrothermally treated nano-HA dispersions enhanced the adhesion strength of SIS on implant surfaces. Importantly, results of the present study demonstrated that human skeletal muscle cell (hSkMC) numbers were not affected by thermally denaturing SIS in nano-HA composite coatings; however, they increased on aqua-sonicated nano-HA/SIS composites compared with SIS alone. Interestingly, thermally denatured SIS that contained aqua-sonicated, hydrothermally treated nano-HA decreased human osteoblasts (hOBs) numbers compared with respective unheated composites; all other composites when thermally denatured did not influence hOB numbers. Results also showed that the number of hOBs increased on nano-HA/SIS composites compared with SIS composites alone. Human mesenchymal stem cell (hMSC) numbers were not affected by the presence of nano-HA in SIS composites. For these reasons, the collective results of this in vitro study demonstrated a technique to increase the coating strength of entheses coatings on implant surfaces (using thermally denatured SIS and aqua-sonicated, hydrothermally prepared nano-HA) while, at the same time, supporting cell functions important for entheses regeneration.

  11. Peroxidation in intestinal mucosa of normal and iron-overloaded rats differing in selenium status

    SciTech Connect

    Mahoney, A.W.; Vega, S. )

    1991-03-15

    Material in the digesta may lead to lipid peroxidation of the intestinal mucosa. To study the effect of Se deficiency ({minus}Se) and Fe overload (++Fe) on mucosal free radical damage, 60 220g rats in four groups were fed torula yeast diet for 20d. Fe-overload was caused in two groups by three IM injections of Fe dextran given on days 4, 9, and 14. Fe-control rats (+Fe) were sham-injected with n-saline. Se-control rats (+Se) were given Na{sub 2}SeO{sub 3}-supplemented drinking water. Se deficiency reduced liver and mucosal glutathione peroxidase activity, but Fe overload did not. Serum, liver and mucosal Fe was higher in the Fe-overloaded rats. Fe and Se treatments did not affect hemoglobin level, but Fe-overload reduced weight gain. Fe overload increased liver and mucosal thiobarbituric acid reactive substances (TBARS), but Se status did not affect them. On days 5-9, CBrCL{sub 3}, an environmental pollutant and lipid peroxidation initiator which must be activated by cytochrome P-450, was gavaged in 10 rats from each group; the higher dose increased mucosal TBARS in Fe-overloaded rats but not Se-deficient ones. But, the lower CBrCL{sub 3} dose did not affect mucosal TBARS. Liver TBARS was not affected by CBrCL{sub 3}; however, the highest liver and mucosal TBARS levels occurred in the {minus}Se++Fe rats given the higher CBrCL{sub 3} dose. Liver cytochrome P-450 activity was not affected by Fe{minus} nor Se status.

  12. Dietary Lactobacillus rhamnosus GG Supplementation Improves the Mucosal Barrier Function in the Intestine of Weaned Piglets Challenged by Porcine Rotavirus.

    PubMed

    Mao, Xiangbing; Gu, Changsong; Hu, Haiyan; Tang, Jun; Chen, Daiwen; Yu, Bing; He, Jun; Yu, Jie; Luo, Junqiu; Tian, Gang

    2016-01-01

    Lactobacillus rhamnosus GG (LGG) has been regarded as a safe probiotic strain. The aim of this study was to investigate whether dietary LGG supplementation could alleviate diarrhea via improving jejunal mucosal barrier function in the weaned piglets challenged by RV, and further analyze the potential roles for apoptosis of jejunal mucosal cells and intestinal microbiota. A total of 24 crossbred barrows weaned at 21 d of age were assigned randomly to 1 of 2 diets: the basal diet and LGG supplementing diet. On day 11, all pigs were orally infused RV or the sterile essential medium. RV infusion increased the diarrhea rate, increased the RV-Ab, NSP4 and IL-2 concentrations and the Bax mRNA levels of jejunal mucosa (P<0.05), decreased the villus height, villus height: crypt depth, the sIgA, IL-4 and mucin 1 concentrations and the ZO-1, occludin and Bcl-2 mRNA levels of jejunal mucosa (P<0.05), and affected the microbiota of ileum and cecum (P<0.05) in the weaned pigs. Dietary LGG supplementation increased the villus height and villus height: crypt depth, the sIgA, IL-4, mucin 1 and mucin 2 concentrations, and the ZO-1, occludin and Bcl-2 mRNA levels of the jejunal mucosa (P<0.05) reduced the Bax mRNA levels of the jejunal mucosa (P<0.05) in weaned pigs. Furthermore, dietary LGG supplementation alleviated the increase of diarrhea rate in the weaned pigs challenged by RV (P<0.05), and relieve the effect of RV infection on the villus height, crypt depth and the villus height: crypt depth of the jejunal mucosa (P<0.05), the NSP4, sIgA, IL-2, IL-4, mucin 1 and mucin 2 concentrations of jejunal mucosa (P<0.05), the ZO-1, occludin, Bax and Bcl-2 mRNA levels of the jejunal mucosa (P<0.05), and the microbiota of ileum and cecum (P<0.05) in the weaned pigs challenged by RV. These results suggest that supplementing LGG in diets alleviated the diarrhea of weaned piglets challenged by RV via inhibiting the virus multiplication and improving the jejunal mucosal barrier function

  13. Dietary Lactobacillus rhamnosus GG Supplementation Improves the Mucosal Barrier Function in the Intestine of Weaned Piglets Challenged by Porcine Rotavirus

    PubMed Central

    Mao, Xiangbing; Gu, Changsong; Hu, Haiyan; Tang, Jun; Chen, Daiwen; Yu, Bing; He, Jun; Yu, Jie; Luo, Junqiu; Tian, Gang

    2016-01-01

    Lactobacillus rhamnosus GG (LGG) has been regarded as a safe probiotic strain. The aim of this study was to investigate whether dietary LGG supplementation could alleviate diarrhea via improving jejunal mucosal barrier function in the weaned piglets challenged by RV, and further analyze the potential roles for apoptosis of jejunal mucosal cells and intestinal microbiota. A total of 24 crossbred barrows weaned at 21 d of age were assigned randomly to 1 of 2 diets: the basal diet and LGG supplementing diet. On day 11, all pigs were orally infused RV or the sterile essential medium. RV infusion increased the diarrhea rate, increased the RV-Ab, NSP4 and IL-2 concentrations and the Bax mRNA levels of jejunal mucosa (P<0.05), decreased the villus height, villus height: crypt depth, the sIgA, IL-4 and mucin 1 concentrations and the ZO-1, occludin and Bcl-2 mRNA levels of jejunal mucosa (P<0.05), and affected the microbiota of ileum and cecum (P<0.05) in the weaned pigs. Dietary LGG supplementation increased the villus height and villus height: crypt depth, the sIgA, IL-4, mucin 1 and mucin 2 concentrations, and the ZO-1, occludin and Bcl-2 mRNA levels of the jejunal mucosa (P<0.05) reduced the Bax mRNA levels of the jejunal mucosa (P<0.05) in weaned pigs. Furthermore, dietary LGG supplementation alleviated the increase of diarrhea rate in the weaned pigs challenged by RV (P<0.05), and relieve the effect of RV infection on the villus height, crypt depth and the villus height: crypt depth of the jejunal mucosa (P<0.05), the NSP4, sIgA, IL-2, IL-4, mucin 1 and mucin 2 concentrations of jejunal mucosa (P<0.05), the ZO-1, occludin, Bax and Bcl-2 mRNA levels of the jejunal mucosa (P<0.05), and the microbiota of ileum and cecum (P<0.05) in the weaned pigs challenged by RV. These results suggest that supplementing LGG in diets alleviated the diarrhea of weaned piglets challenged by RV via inhibiting the virus multiplication and improving the jejunal mucosal barrier function

  14. The role of intestinal epithelial barrier function in the development of NEC

    PubMed Central

    Halpern, Melissa D; Denning, Patricia W

    2015-01-01

    The intestinal epithelial barrier plays an important role in maintaining host health. Breakdown of intestinal barrier function is known to play a role in many diseases such as infectious enteritis, idiopathic inflammatory bowel disease, and neonatal inflammatory bowel diseases. Recently, increasing research has demonstrated the importance of understanding how intestinal epithelial barrier function develops in the premature neonate in order to develop strategies to promote its maturation. Optimizing intestinal barrier function is thought to be key to preventing neonatal inflammatory bowel diseases such as necrotizing enterocolitis. In this review, we will first summarize the key components of the intestinal epithelial barrier, what is known about its development, and how this may explain NEC pathogenesis. Finally, we will review what therapeutic strategies may be used to promote optimal development of neonatal intestinal barrier function in order to reduce the incidence and severity of NEC. PMID:25927016

  15. Spray-dried animal plasma prevents the effects of Staphylococcus aureus enterotoxin B on intestinal barrier function in weaned rats.

    PubMed

    Pérez-Bosque, Anna; Amat, Concepció; Polo, Javier; Campbell, Joy M; Crenshaw, Joe; Russell, Louis; Moretó, Miquel

    2006-11-01

    In this study, we investigated intestinal barrier function during inflammation as well as the effects of dietary supplementation with porcine spray-dried animal plasma (SDAP) proteins and porcine immunoglobulin concentrate (IC). Wistar Lewis rats were fed from d 21 (weaning) until d 34 or 35 either a control diet or a diet containing SDAP or IC. On d 30 and d 33, rats received an intraperitoneal dose of Staphylococcus aureus enterotoxin B (SEB; 0.5 mg/kg body wt; groups SEB, SEB-SDAP, and SEB-IC). SEB reduced the potential difference across the jejunum by 60%, the short-circuit current by 70%, and Na-K-ATPase activity in intestinal mucosa (all P < 0.05). The fluxes of dextran flux (4 kDa) and horseradish peroxidase (HRP, 40 kDa) across the intestinal wall also increased in SEB-treated rats (P < 0.01, P = 0.068, respectively). SEB also increased HRP flux across the paracellular space (P < 0.05). Moreover, SEB-treated rats had a reduced expression of tight junction proteins, such as ZO-1 (10% reduction; P < 0.05) and beta-catenin (20% reduction; P < 0.05). Dietary supplementation with SDAP or IC prevented dextran (P < 0.05) and HRP (P < 0.05) paracellular flux across the intestinal epithelium. SDAP supplementation also prevented SEB effects on Na-K-ATPase activity (P < 0.05). In our model of SEB-induced intestinal inflammation, the increased permeability across the intestinal mucosa was due to the lower expression of tight junction proteins, an effect that can be prevented by both SDAP and IC supplementation.

  16. Cavitation of mesenteric lymph nodes, splenic atrophy, and a flat small intestinal mucosa. Report of six cases.

    PubMed

    Matuchansky, C; Colin, R; Hemet, J; Touchard, G; Babin, P; Eugene, C; Bergue, A; Zeitoun, P; Barboteau, M A

    1984-09-01

    This study describes, in 6 patients with a flat small intestinal mucosa and splenic atrophy, a particular lesion of the mesenteric lymph nodes termed "cavitation." In 4 women and 2 men with abdominal mass, intestinal obstruction, or suspected celiac disease-associated lymphoma, unusual pseudocystic lymph node lesions were found in the jejunal or jejunoileal mesentery. These lesions consisted histologically of a large central cavity occupied by hyaline-type material and surrounded by fibrous tissue and remnants of lymph node structures. There was no histologic evidence of malignant lymphoma or mesenteric panniculitis. Diffuse subtotal villous atrophy involving at least the jejunum was found in each case, together with unequivocal biological and morphological evidence of splenic atrophy, severe malabsorption, and a history of chronic or childhood diarrhea. HLA B8 or DR3, or both, was present in 4 of 4 cases; dermatitis herpetiformis was present in 1 case. An unequivocal mucosal response to a gluten-free diet was observed in 2 cases. Four patients died of cachexia or hyposplenism-related infections. We conclude that cavitation of mesenteric lymph nodes is an original feature which may be associated with splenic atrophy and a flat small intestinal mucosa; some of these patients may have celiac disease. Pathogenesis is unknown.

  17. Dietary glutamine, glutamic acid and nucleotides increase the carbon turnover (δ 13C) on the intestinal mucosa of weaned piglets.

    PubMed

    Amorim, A B; Berto, D A; Saleh, M A D; Miassi, G M; Ducatti, C

    2017-02-10

    This study aimed at evaluating the influence of dietary glutamine, glutamic acid and nucleotides on duodenal and jejunal carbon turnover, and on mucosa morphometry of piglets weaned at an age of 21 days. The diets were: additive-free diet - control (C); 1% of glutamine (G); 1% of glutamic acid (GA); and 1% of nucleotides (N). In intestinal mucosa morphometry trial, 65 animals were used. At day 0 (baseline), five animals were slaughtered to determine the villus height (VH), crypt depth (CD), VH : CD ratio and villi density (VD). The remaining 60 animals were allocated into a randomized block design with 4×3 factorial arrangement (four diets: C - control, G - glutamine, GA - glutamic acid and N - nucleotides; three slaughter ages: 7, 14 and 21 days post-weaning) with five piglets slaughtered per treatment. In carbon turnover trial, 123 animals were used. At day 0 (baseline), three animals were slaughtered to quantify the δ 13C half-life (T50%) and the 99% carbon substitution (T99%) on intestinal mucosa. The remaining 120 animals were blocked by three weight categories (light, medium and heavy) and, randomly assigned to pen with the same four diets from the previous trial with one piglet slaughtered per weight category per treatment at days 1, 2, 4, 5, 7, 9, 13, 20, 27 and 49 after weaning. Morphometric analyses have yielded no consistent results regarding the action of the evaluated additives, and few reproducible age-related effects. The N diets determined lower T50% values (5.18 days) and T99% (17.21 days) than G and C diets (T50%=7.29, 7.58 days and T99%=24.22, 25.17 days, respectively) in the duodenal mucosa. In jejunum, the N, GA and G diets determined the lowest T50% means (4.9, 6.2 and 6.7 days, respectively) and T99% means (15.34, 21.10 and 21.84 days, respectively) in comparison with C diets (T50%=7.44 and T99%=24.72 days). The inclusion of the additives in the diets of piglets accelerated the carbon turnover in piglets during the post-weaning period. The

  18. Prostaglandin E1 maintains structural integrity of intestinal mucosa and prevents bacterial translocation during experimental obstructive jaundice.

    PubMed

    Gurleyik, Emin; Coskun, Ozgur; Ustundag, Nil; Ozturk, Elif

    2006-01-01

    The absence of bile in the gut lumen induces mucosal injury and promotes bacterial translocation (BT). Prostaglandin E (PGE) has a protective effect on the mucosal layer of the alimentary tract. We hypothesize that PGE1 may prevent BT by its beneficial action on the mucosa of the small bowel. Thirty Wistar albino rats were divided equally into 3 groups; Group 1 (control) underwent sham laparotomy, group 2 obstructive jaundice (OJ) and group 3 (OJ + PGE1) underwent common bile duct (CBD) ligation and transection. Groups 1 and 2 received; 1 mL normal saline and group 3 received 40 mg of the PGE1 analogue misoprostol dissolved in 1 mL normal saline administered by orogastric tube once daily. After 7 days, laparotomy and collection of samples for laboratory analyses were performed, including bacteriological analysis of intestine, mesenteric lymph nodes (MLNs), and blood, and histopathologic examination of intestinal mucosa to determine mucosal thickness and structural damage. Serum bilirubin and alkaline phosphatase levels confirmed OJ in all animals with CBD transection. The mucosal damage score was significantly reduced in jaundiced animals receiving PGE1 compared to jaundiced controls (2.15 +/- 0.74 vs 5.3 +/- 0.59; p < .00001) and mucosal thickness was greater (607 +/- 59.1 microm vs. 393 +/- 40.3 microm; p < .00001). The incidence of BT to MLNs decreased from 90% to 30% (p < .02) when jaundiced rats received PGE1. PGE1 treatment reduced the detection rate of viable enteric bacteria in the blood from 60% to 10% (p < .057). We conclude that administration of PGE1 provides protection against OJ-induced atrophy and damage of intestinal mucosa, and thereby prevents translocation of enteric bacteria to underlying tissues.

  19. Homeostasis alteration within small intestinal mucosa after acute enteral refeeding in total parenteral nutrition mouse model

    PubMed Central

    Feng, Yongjia; Barrett, Meredith; Hou, Yue; Yoon, Hong Keun; Ochi, Takanori

    2015-01-01

    Feeding strategies to care for patients who transition from enteral nutrient deprivation while on total parenteral nutrition (TPN) to enteral feedings generally proceed to full enteral nutrition once the gastrointestinal tract recovers; however, an increasing body of literature suggests that a subgroup of patients may actually develop an increased incidence of adverse events, including death. To examine this further, we studied the effects of acute refeeding in a mouse model of TPN. Interestingly, refeeding led to some beneficial effects, including prevention in the decline in intestinal epithelial cell (IEC) proliferation. However, refeeding led to a significant increase in mucosal expression of proinflammatory cytokines, including tumor necrosis factor-α (TNF-α), as well as an upregulation in Toll-like receptor 4 (TLR-4). Refeeding also failed to prevent TPN-associated increases in IEC apoptosis, loss of epithelial barrier function, and failure of the leucine-rich repeat-containing G protein-coupled receptor 5-positive stem cell expression. Transitioning from TPN to enteral feedings led to a partial restoration of the small bowel microbial population. In conclusion, while acute refeeding led to some restoration of normal gastrointestinal physiology, enteral refeeding led to a significant increase in mucosal inflammatory markers and may suggest alternative strategies to enteral refeeding should be considered. PMID:26635320

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

    PubMed Central

    Williams, Benjamin B.; Tebbutt, Niall C.; Buchert, Michael; Putoczki, Tracy L.; Doggett, Karen; Bao, Shisan; Johnstone, Cameron N.; Masson, Frederick; Hollande, Frederic; Burgess, Antony W.; Scott, Andrew M.; Ernst, Matthias; Heath, Joan K.

    2015-01-01

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

  1. Food Derived Bioactive Peptides and Intestinal Barrier Function

    PubMed Central

    Martínez-Augustin, Olga; Rivero-Gutiérrez, Belén; Mascaraque, Cristina; Sánchez de Medina, Fermín

    2014-01-01

    A wide range of food-derived bioactive peptides have been shown to exert health-promoting actions and are therefore considered functional foods or nutraceuticals. Some of these actions are related to the maintenance, reinforcement or repairment of the intestinal barrier function (IBF) whose role is to selectively allow the absorption of water, nutrients and ions while preventing the influx of microorganisms from the intestinal lumen. Alterations in the IBF have been related to many disorders, such as inflammatory bowel disease or metabolic syndrome. Components of IBF are the intestinal epithelium, the mucus layer, secretory immunoglobulin A and cells of the innate and adaptive immune systems. Here we review the effects of food derived bioactive peptides on these IBF components. In vitro and in vivo effects, both in healthy and disease states, have been reviewed. Although limited, the available information indicates a potential for food-derived peptides to modify IBF and to contribute to disease treatment, but further research is needed to better isolate responsible peptides, and to help define their mode of action. PMID:25501338

  2. Food derived bioactive peptides and intestinal barrier function.

    PubMed

    Martínez-Augustin, Olga; Rivero-Gutiérrez, Belén; Mascaraque, Cristina; Sánchez de Medina, Fermín

    2014-12-09

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

  3. The cell cycle time in the flat (avillous) mucosa of the human small intestine.

    PubMed

    Wright, N; Watson, A; Morley, A; Appleton, D; Marks, J; Douglas, A

    1973-08-01

    A hyperproductive mucosal state in gluten-sensitive enteropathy has been proposed on the basis of an elevated mitotic index, but this parameter is dependent on the mitotic duration when used as an index of proliferative status. The mitotic duration was therefore measured in two control patients with normal villous mucosae and in two patients with the flat avillous mucosa of untreated gluten-sensitive enteropathy, using two different stathmokinetic techniques with vincristine. No significant difference in mitotic duration was found but values obtained for cell cycle time showed a halving in the flat mucosae. An increased rate of cell production in the small bowel mucosa of untreated gluten-sensitive enteropathy is thus confirmed.

  4. Regulation of GLUT5 gene expression in rat intestinal mucosa: regional distribution, circadian rhythm, perinatal development and effect of diabetes.

    PubMed Central

    Castelló, A; Gumá, A; Sevilla, L; Furriols, M; Testar, X; Palacín, M; Zorzano, A

    1995-01-01

    1. GLUT5 gene expression was studied in small intestine under a variety of conditions characterized by altered intestinal absorption of monosaccharides. 2. RNA-blotting studies showed that GLUT5 mRNA was abundantly expressed in rat and rabbit intestine and kidney, but it was not detected in heart or brown adipose tissue. GLUT5 mRNA levels were higher in the upper segments of the small intestine (duodenum and proximal jejunum) than in the lower segments (distal jejunum and ileum). 3. The intestinal expression of GLUT5 mRNA in rat proximal jejunum showed circadian rhythm. A 12-fold increase in GLUT5 mRNA levels was detected at the end of the light cycle and at the beginning of the dark cycle when compared with the early light period. In keeping with this, GLUT5 protein content in brush-border membranes was also increased at the beginning of the dark cycle compared with that in the light period. 4. In streptozotocin-induced diabetes an 80% increase in GLUT5 mRNA levels in mucosa from the proximal jejunum was detected under conditions in which enhanced intestinal absorption of monosaccharides has been reported. 5. The intestinal expression of GLUT5 mRNA showed regulation during perinatal development. Levels of GLUT5 mRNA were low during fetal life, increased progressively during the postnatal period and reached levels comparable with the adult state after weaning. Weaning on to a high-fat diet partially prevented the induction of GLUT5 gene expression. 6. Our results indicate that GLUT5 gene expression is tightly regulated in small intestine. Regulation involves maximal expression in the upper part of the small intestine, circadian rhythm, developmental regulation dependent on the fat and carbohydrate content in the diet at weaning and enhanced expression in streptozotocin-induced diabetes. Furthermore, changes observed in intestinal GLUT5 expression correlate with reported alterations in intestinal absorption of fructose. This suggests a regulatory role for GLUT5 in

  5. [Effect of curcumin on intestinal mucosal mechanical barrier in rats with non-alcoholic fatty liver disease].

    PubMed

    Hou, H T; Qiu, Y M; Zhao, H W; Li, D H; Liu, Y T; Wang, Y Z; Su, S H

    2017-02-20

    Objective: To investigate the effect of curcumin on intestinal mucosal mechanical barrier in rats with non-alcoholic fatty liver disease. Methods: A total of 30 male Sprague-Dawley rats were equally divided into normal control group, model group, and curcumin intervention group. The rats in the model group and the curcumin intervention group were given high-fat feed for 16 weeks, and those in the curcumin intervention group were given curcumin 200 mg/kg/day by gavage once a day after 8 weeks of high-fat feeding. The rats were sacrificed at the end of week 16. A light microscope was used to observe pathological changes in the liver, an electron microscope was used to observe the tight junction of the intestinal mucosa, an automatic biochemical analyzer was used to measure the serum levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST), chromogenic substrate Limulus amebocyte lysate assay was used to measure plasma lipopolysaccharide (LPS) level, spectrophotometric method was used to measure the activity of serum diamine oxidase, ELISA was used to measure the serum level of tumor necrosis factor-α (TNFα), and immunohistochemistry was used to measure the expression of the tight junction protein occludin. One-way ANOVA test and SNK-q test were used for statistical analysis. Results: Under the light microscope, the control group had no hepatocyte steatosis, the model group had significant hepatocyte steatosis and inflammatory cell infiltration, and the curcumin intervention group had reduced hepatocyte steatosis and inflammatory cell infiltration. Under the electron microscope, the control group had a clear and complete structure of the tight junction of the intestinal mucosa and normal structures of mitochondria and endoplasmic reticulum; in the model group, the structure of the tight junction of the intestinal mucosa was destroyed, the intercellular space was widened, the desmosomes had a loose structure, there was edema in some mitochondria

  6. H19 Long Noncoding RNA Regulates Intestinal Epithelial Barrier Function via MicroRNA 675 by Interacting with RNA-Binding Protein HuR

    PubMed Central

    Zou, Tongtong; Jaladanki, Suraj K.; Liu, Lan; Xiao, Lan; Chung, Hee Kyoung; Wang, Jun-Yao; Xu, Yan; Gorospe, Myriam

    2016-01-01

    The disruption of the intestinal epithelial barrier function occurs commonly in various pathologies, but the exact mechanisms responsible are unclear. The H19 long noncoding RNA (lncRNA) regulates the expression of different genes and has been implicated in human genetic disorders and cancer. Here, we report that H19 plays an important role in controlling the intestinal epithelial barrier function by serving as a precursor for microRNA 675 (miR-675). H19 overexpression increased the cellular abundance of miR-675, which in turn destabilized and repressed the translation of mRNAs encoding tight junction protein ZO-1 and adherens junction E-cadherin, resulting in the dysfunction of the epithelial barrier. Increasing the level of the RNA-binding protein HuR in cells overexpressing H19 prevented the stimulation of miR-675 processing from H19, promoted ZO-1 and E-cadherin expression, and restored the epithelial barrier function to a nearly normal level. In contrast, the targeted deletion of HuR in intestinal epithelial cells enhanced miR-675 production in the mucosa and delayed the recovery of the gut barrier function after exposure to mesenteric ischemia/reperfusion. These results indicate that H19 interacts with HuR and regulates the intestinal epithelial barrier function via the H19-encoded miR-675 by altering ZO-1 and E-cadherin expression posttranscriptionally. PMID:26884465

  7. Mucosal injuries due to ribosome-inactivating stress and the compensatory responses of the intestinal epithelial barrier.

    PubMed

    Moon, Yuseok

    2011-10-01

    Ribosome-inactivating (ribotoxic) xenobiotics are capable of using cleavage and modification to damage 28S ribosomal RNA, which leads to translational arrest. The blockage of global protein synthesis predisposes rapidly dividing tissues, including gut epithelia, to damage from various pathogenic processes, including epithelial inflammation and carcinogenesis. In particular, mucosal exposure to ribotoxic stress triggers integrated processes that are important for barrier regulation and re-constitution to maintain gut homeostasis. In the present study, various experimental models of the mucosal barrier were evaluated for their response to acute and chronic exposure to ribotoxic agents. Specifically, this review focuses on the regulation of epithelial junctions, epithelial transporting systems, epithelial cytotoxicity, and compensatory responses to mucosal insults. The primary aim is to characterize the mechanisms associated with the intestinal epithelial responses induced by ribotoxic stress and to discuss the implications of ribotoxic stressors as chemical modulators of mucosa-associated diseases such as ulcerative colitis and epithelial cancers.

  8. Alteration of the intestinal barrier and GLP2 secretion in Berberine-treated type 2 diabetic rats.

    PubMed

    Shan, C Y; Yang, J H; Kong, Y; Wang, X Y; Zheng, M Y; Xu, Y G; Wang, Y; Ren, H Z; Chang, B C; Chen, L M

    2013-09-01

    For centuries, Berberine has been used in the treatment of enteritis in China, and it is also known to have anti-hyperglycemic effects in type 2 diabetic patients. However, as Berberine is insoluble and rarely absorbed in gastrointestinal tract, the mechanism by which it works is unclear. We hypothesized that it may act locally by ameliorating intestinal barrier abnormalities and endotoxemia. A high-fat diet combined with low-dose streptozotocin was used to induce type 2 diabetes in male Sprague Dawley rats. Berberine (100 mg/kg) was administered by lavage to diabetic rats for 2 weeks and saline was given to controls. Hyperinsulinemia and insulin resistance improved in the Berberine group, although there was no significant decrease in blood glucose. Berberine treatment also led to a notable restoration of intestinal villi/mucosa structure and less infiltration of inflammatory cells, along with a decrease in plasma lipopolysaccharide (LPS) level. Tight junction protein zonula occludens 1 (ZO1) was also decreased in diabetic rats but was restored by Berberine treatment. Glutamine-induced glucagon-like peptide 2 (GLP2) secretion from ileal tissue decreased dramatically in the diabetic group but was restored by Berberine treatment. Fasting insulin, insulin resistance index, plasma LPS level, and ZO1 expression were significantly correlated with GLP2 level. In type 2 diabetic rats, Berberine treatment not only augments GLP2 secretion and improves diabetes but is also effective in repairing the damaged intestinal mucosa, restoring intestinal permeability, and improving endotoxemia. Whether these effects are mechanistically related will require further studies, but they certainly support the hypothesis that Berberine acts via modulation of intestinal function.

  9. [Effect of gaseous hypoxic mixture GHM-10 on the intestinal death of Wistar rats and Na+,K+-ATPase activity of the plasma membrane of the small intestine mucosa after irradiation].

    PubMed

    Strelkov, R B; Dvoretskiĭ, A I; Kucherenko, N G

    1986-01-01

    It was shown that gas hypoxic mixture containing O2 (10%) and N2 (90%) significantly decreases "intestinal" death of Wistar rats on the 5th day following irradiation and normalizes Na+,K+-ATPase activity of the small intestine mucosa plasma membranes.

  10. Inactivation of corticosteroids in intestinal mucosa by 11 beta-hydroxysteroid: NADP oxidoreductase (EC 1. 1. 1. 146)

    SciTech Connect

    Burton, A.F.; Anderson, F.H.

    1983-10-01

    Activity of the enzyme 11 beta-hydroxysteroid:NADP oxidoreductase (EC 1.1.1.146) in human intestinal mucosa was determined by incubating scraped mucosa with /sup 3/H-cortisone and /sup 14/C-cortisol; these steroids were then extracted, separated chromatographically, and the radioactivity assayed to determine simultaneously both reductase and dehydrogenase activities. This was the only significant metabolic alteration which the substrate underwent. Only two cases had slight (5 and 13%) reductase activity. In 35 patients, 16 male and 19 female, including seven cases of Crohn's disease, three ulcerative colitis, five diverticulitis, two undergoing surgery for repair of injuries and 18 for carcinoma of colon or rectum, cortisol was converted to cortisone in 15 min with a wide range of values distributed uniformly up to 85% dehydrogenation, with a mean of 42%. When tissue homogenates were fortified with coenzymes, excess NADPH lowered dehydrogenase activity 81%; excess NADP increased dehydrogenase activity 2-fold in three cases. It is possible that a value is characteristic of an individual but perhaps more likely enzyme activity varies with metabolic events involving changes in the coenzyme levels in mucosa, and a random sampling might be expected to yield such a distribution of values. In any event, where activity is high most of the cortisol is inactivated within minutes. It is suggested that synthetic corticoids which escape such metabolic alteration might, except during pregnancy, prove superior in the treatment of conditions such as inflammatory bowel disease.

  11. Isolation of lactic acid bacteria bound to the porcine intestinal mucosa and an analysis of their moonlighting adhesins

    PubMed Central

    KINOSHITA, Hideki; OHUCHI, Satoko; ARAKAWA, Kensuke; WATANABE, Masamichi; KITAZAWA, Haruki; SAITO, Tadao

    2016-01-01

    The adhesion of lactic acid bacteria (LAB) to the intestinal mucosa is one of the criteria in selecting for probiotics. Eighteen LAB were isolated from porcine intestinal mucin (PIM): ten strains of Lactobacillus, six strains of Weissella, and two strains of Streptococcus. Using sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) for phosphate-buffered saline (PBS) extracts from the LAB, many bands were detected in half of the samples, while a few and/or no clear bands were detected in the other half. All six of the selected LAB showed adhesion to PIM. L. johnsonii MYU 214 and MYU 221 showed adhesion at more than 10%. W. viridescens MYU 208, L. reuteri MYU 213, L. mucosae MYU 225, and L. agilis MYU 227 showed medium levels of adhesion at 5.9–8.3%. In a comprehensive analysis for the adhesins in the PBS extracts using a receptor overlay analysis, many moonlighting proteins were detected and identified as candidates for adhesins: GroEL, enolase, and elongation factor Tu in MYU 208; peptidase C1, enolase, formyl-CoA transferase, phosphoglyceromutase, triosephosphate isomerase, and phosphofructokinase in MYU 221; and DnaK, enolase, and phosphoglycerate kinase in MYU 227. These proteins in the PBS extracts, which included such things as molecular chaperones and glycolytic enzymes, may play important roles as adhesins. PMID:27867805

  12. Effect of chito-oligosaccharide on growth performance, intestinal barrier function, intestinal morphology and cecal microflora in weaned pigs.

    PubMed

    Yang, C M; Ferket, P R; Hong, Q H; Zhou, J; Cao, G T; Zhou, L; Chen, A G

    2012-08-01

    A total of 180 weanling pigs (21 ± 3 d of age; 5.98 ± 0.04 kg) were used to investigate the effect of chito-oligosaccharide (COS) on growth performance, intestinal barrier function, intestinal morphology, and cecal microflora. Based on initial BW, gender and litter, the pigs were given 5 treatments during a 14-d feeding experiment, including a basal diet (control), 3 diets with COS supplementation (200, 400, or 600 mg/kg), and a diet with colistin sulfate (CSE) supplementation (20 mg/kg). Six randomly selected pigs from each treatment were used to collect serum, duodenal, jejunal, ileal, and cecal samples on d 7 and 14 postweaning. From d 1 to 7 postweaning, pigs fed COS or CSE had greater ADG and ADFI compared with the control pigs. From d 1 to 14, diets with either 400 or 600 mg/kg COS, or 20 mg/kg CSE increased (P < 0.05) ADG and G:F compared with the control diet. No significant differences were observed in ADG, ADFI, and G:F between the pigs fed COS and CSE. Pigs fed either 400 or 600 mg/kg COS, or 20 mg/kg CSE had less (P < 0.05) diamine oxidase (DAO) in the serum, but greater concentration of (P < 0.05) DAO in jejunal mucosa, than the control pigs on d 7 postweaning. Treatments did not affect villous height and crypt depth of the duodenum, jejunum, or ileum. Pigs fed COS at 400 mg/kg had greater (P < 0.05) concentration of Bifidobacteria and Lactobacilli in the cecum than pigs fed the control diet and CSE diet on d 7 postweaning. Supplementation of COS or CSE decreased (P < 0.05) the population of cecal Staphylococcus aureus compared with the control diet on d 7 postweaning. The number of cecal Bifidobacteria in pigs fed 600 mg/kg COS was greater (P < 0.05) than that of pigs fed the control diet or CSE diet on d 14 postweaning. No significant differences were observed in Escherichia coli counts in the cecum among treatments. The present results indicate that dietary supplementation of COS at 400 or 600 mg/kg promotes growth performance and improves gut

  13. The biogenic amine tyramine modulates the adherence of Escherichia coli O157:H7 to intestinal mucosa.

    PubMed

    Lyte, Mark

    2004-05-01

    The environmental factors that influence the ability of Escherichia coli O157:H7 to attach to the intestinal mucosa are incompletely understood. In the present study, the ability of one of the most common biogenic amines present in food, tyramine, to influence the ability of E. coli O157:H7 to adhere to murine cecal mucosa was examined. Ex vivo full-thickness sheets of murine cecum were mounted in Ussing chambers, which preserved the enteric nervous system innervation of the luminal epithelia and thereby allowed us to achieve a closer approximation of bacterial adherence than would be encountered in vivo. After exposure of the luminal aspect of the cecum to tyramine, E. coli O157:H7 was added for 90 min. The cecal tissue was then removed and washed, and adhered E. coli O157:H7 was enumerated using a selective medium. Tyramine significantly increased E. coli O157:H7 adherence to cecal mucosa when compared to that of controls. The 50% effective concentration of tyramine was 92.6 microM. Specific adrenergic antagonists were then employed to examine whether the effect of tyramine was mediated through alpha- or beta-adrenergic receptors on the intestinal tissue. Pretreatment of tissues with either the alpha-adrenergic receptor antagonist phentolamine or the beta-adrenergic receptor antagonist propranolol prevented the action of tyramine. Measurement of active transepithelial ion transport and ionic permeability in the cecal sheets before and after the addition of tyramine and E. coli O157:H7 did not show any impairment of tissue viability or transepithelial conductance. Further, tyramine did not influence either the growth of E. coli O157:H7 or the expression of the intimin attachment factor. The present findings suggest that biogenic amines, such as tyramine, present within the food matrix influence host susceptibility to E. coli O157:H7 infection.

  14. Rapamycin, a specific inhibitor of the target of rapamycin complex 1, disrupts intestinal barrier integrity in broiler chicks.

    PubMed

    Liu, S Q; Zhao, J P; Fan, X X; Liu, G H; Jiao, H C; Wang, X J; Sun, S H; Lin, H

    2016-04-01

    To uncover the molecular mechanisms underlying the intestinal barrier integrity, this study determined whether the rapamycin (RAPA)-sensitive target of rapamycin complex 1 (TORC1) pathway was involved in this process. Three groups of 4-day-old male chicks were randomly subjected to one of the following treatments for 6 days: high-dose RAPA [a specific inhibitor of TORC1; an intraperitoneal injection of 1.0 mg/kg body weight (BW), once daily at 09:00 hours], low-dose RAPA (0.4 mg/kg BW) and RAPA vehicle (control). Results showed that the RAPA treatment increased mortality, while decreasing villus height (p < 0.01), claudin 1 expression, content of immunoglobulin A (IgA), extent of TORC1 phosphorylation (p < 0.05), ratio of villus height to crypt depth (p < 0.01), and population of IgA-positive B cells in intestinal mucosa, particularly for the jejunum. Some aspects of these responses were dose dependent and appeared to result from weight loss. Together, RAPA exerts the expected inhibition of small intestinal development and IgA production in birds, suggesting the important role of TORC1 in gut barrier integrity.

  15. [Atrophy in the mucosa neighboring an intestinal-type gastric adenocarcinoma by comparing the Sydney vs. OLGA systems].

    PubMed

    Ramírez-Mendoza, Pablo; Hernández-Briseño, Liliana; Casarrubias-Ramírez, Moisés; Alvarado-Cabrero, Isabel; Ángeles-Garay, Ulises

    2015-01-01

    Introducción: el carcinoma gástrico ocasiona al año unas 700 000 muertes en el mundo. El objetivo de este artículo es evaluar la atrofia en la mucosa vecina al adenocarcinoma gástrico tipo intestinal comparando los sistemas Sídney y OLGA. Diferencias en el rendimiento diagnóstico impulsarían el empleo de alguno. Métodos: estudiamos 28 sujetos con adenocarcinoma gástrico tipo intestinal (Lauren), que comparamos con 32 casos sin neoplasia, ambos grupos con gastrectomía total. Dos patólogos evaluaron la atrofia en el epitelio de cuerpo y antro no neoplásico con los sistemas Sídney y OLGA. Se obtuvieron la media, mediana y distribución de frecuencias por escala de medición, así como la distribución de las variables del estudio. Se calculó la sensibilidad, especificidad y los valores predictivos para cáncer gástrico gracias a dicotomizar las escalas con resultado positivo y negativo para atrofia avanzada. Resultados: veinticuatro de 28 casos con adenocarcinoma gástrico tipo intestinal mostraron atrofia avanzada con OLGA con una sensibilidad y especificidad de 77 y 85 % respectivamente. Con el sistema Sídney, 4 de 28 mostraron atrofia avanzada con una sensibilidad y especificidad de 14 y 100 % respectivamente. Conclusiones: el sistema OLGA tiene elevada sensibilidad y especificidad (77 y 85 % respectivamente) para reconocer cambios preneoplásicos en la mucosa vecina al cáncer gástrico. Empero, OLGA no mostró atrofia avanzada en adenomas foveolares con displasia de alto grado, ni en adenocarcinomas en las porciones proximales del estómago.

  16. Morphologic observation of mucosa-associated lymphoid tissue in the large intestine of Bactrian camels (Camelus bactrianus).

    PubMed

    ZhaXi, Yingpai; Wang, Wenhui; Zhang, Wangdong; Gao, Qiang; Guo, Minggang; Jia, Shuai

    2014-07-01

    The structure and distribution of the mucosa-associated lymphoid tissue (MALT) throughout the large intestine of 10 Bactrian camels were comparatively studied by anatomical and histological methods. The results showed that Peyer's patches (PPs) were mainly located on the mucosal surfaces of the entire ileocecal orifice, the beginning of the cecum and the first third of the colon. The shape of PPs gradually changed from "scrotiform" to "faviform" along the large intestine with the scrotiform PP as the major type in the ileocecal orifice. The distribution density also gradually decreased from the ileocecal orifice to the colon. The histological observations further revealed that the MALT in the form of PPs or isolated lymphoid follicles (ILF) and lamina propria lymphocytes was mainly present in the lamina propria and submucosa from the entire ileocecal orifice, where the muscularis mucosa is usually incomplete, to the colonic forepart. In addition, lymphoid tissue was much more abundant in the lamina propria and submucosa of the ileocecal orifice as compared to the cecum and colon. Statistically, the MALT of the ileocecal orifice contained a higher number of lymphoid follicles (37.7/10 mm(2) ) than that of the cecum, colon, or rectum (P < 0.05). The germinal centers of the lymphoid follicles were clearly visible. Together, our data suggest that the ileocecal orifice constitutes the main inductive site for the mucosal immunity in the large intestine of the Bactrian camel; and that scrotiform PPs are likely to the result of long-term adaptation of the Bactrian camel to the harsh living environment.

  17. No holes barred: Invasion of the intestinal mucosa by Mycobacterium avium subspecies paratuberculosis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The infection biology of Mycobacterium avium subspecies paratuberculosis (MAP) has recently crystalized with added details surrounding intestinal invasion. The involvement of pathogen-derived effector proteins such as the major membrane protein, oxidoreductase and fibronectin attachment proteins hav...

  18. Mechanisms of Intestinal Epithelial Barrier Dysfunction by Adherent-Invasive Escherichia coli.

    PubMed

    Shawki, Ali; McCole, Declan F

    2017-01-01

    Pathobiont expansion, such as that of adherent-invasive Escherichia coli (AIEC), is an emerging factor associated with inflammatory bowel disease. The intestinal epithelial barrier is the first line of defense against these pathogens. Inflammation plays a critical role in altering the epithelial barrier and is a major factor involved in promoting the expansion and pathogenesis of AIEC. AIEC in turn can exacerbate intestinal epithelial barrier dysfunction by targeting multiple elements of the barrier. One critical element of the epithelial barrier is the tight junction. Increasing evidence suggests that AIEC may selectively target protein components of tight junctions, leading to increased barrier permeability. This may represent one mechanism by which AIEC could contribute to the development of inflammatory bowel disease. This review article discusses potential mechanisms by which AIEC can disrupt epithelial tight junction function and intestinal barrier function.

  19. Intestinal epithelial barrier function and tight junction proteins with heat and exercise.

    PubMed

    Dokladny, Karol; Zuhl, Micah N; Moseley, Pope L

    2016-03-15

    A single layer of enterocytes and tight junctions (intercellular multiprotein complexes) form the intestinal epithelial barrier that controls transport of molecules through transcellular and paracellular pathways. A dysfunctional or "leaky" intestinal tight junction barrier allows augmented permeation of luminal antigens, endotoxins, and bacteria into the blood stream. Various substances and conditions have been shown to affect the maintenance of the intestinal epithelial tight junction barrier. The primary focus of the present review is to analyze the effects of exertional or nonexertional (passive hyperthermia) heat stress on tight junction barrier function in in vitro and in vivo (animals and humans) models. Our secondary focus is to review changes in tight junction proteins in response to exercise or hyperthermic conditions. Finally, we discuss some pharmacological or nutritional interventions that may affect the cellular mechanisms involved in maintaining homeostasis of the intestinal epithelial tight junction barrier during heat stress or exercise.

  20. Intestinal epithelial barrier function and tight junction proteins with heat and exercise

    PubMed Central

    Zuhl, Micah N.; Moseley, Pope L.

    2015-01-01

    A single layer of enterocytes and tight junctions (intercellular multiprotein complexes) form the intestinal epithelial barrier that controls transport of molecules through transcellular and paracellular pathways. A dysfunctional or “leaky” intestinal tight junction barrier allows augmented permeation of luminal antigens, endotoxins, and bacteria into the blood stream. Various substances and conditions have been shown to affect the maintenance of the intestinal epithelial tight junction barrier. The primary focus of the present review is to analyze the effects of exertional or nonexertional (passive hyperthermia) heat stress on tight junction barrier function in in vitro and in vivo (animals and humans) models. Our secondary focus is to review changes in tight junction proteins in response to exercise or hyperthermic conditions. Finally, we discuss some pharmacological or nutritional interventions that may affect the cellular mechanisms involved in maintaining homeostasis of the intestinal epithelial tight junction barrier during heat stress or exercise. PMID:26359485

  1. Experimental adenomas and carcinomas of the large intestine behave as distinct entities: most carcinomas arise de novo in flat mucosa.

    PubMed

    Maskens, A P; Dujardin-Loits, R M

    1981-01-01

    Detailed histologic analyses were performed on tumors of the large intestine obtained in 152 dimethylhydrazine (DMH)-treated rats. Of a total 539 glandular neoplasms, 45 were benign; 494 (92%) were locally invasive; of which 222 (41%) were invading the muscularis propria. One-hundred-forty-one tumors were smaller than or equal to 3mm in diameter. Among those, 127 (90%) were invasive. In addition to macroscopic nodules, several appeared after longer latency periods than did serial sections of flat mucosa. The benign polyps usually appeared after longer latency periods than did carcinomas. A review of the literature indicates that in the majority of rat experiments most or all DMH-induced tumors were frequently reported. All these data constitute strong evidence that most experimental adenocarcinomas do arise de novo in flat mucosa, i.e., without a prior adenoma stage. However, most DMH-induced tumors in mice were reported to be adenomas, either alone or coexisting with carcinomas. It is suggested that "de novo arising carcinomas" and adenomatous polyps, which are both inducible by the same carcinogens, and which can coexist in some experimental systems, nonetheless constitute independent and distinct pathologic entities; they can be separated by genetic susceptibility.

  2. Stimulation of butyrate production in the large intestine of weaning piglets by dietary fructooligosaccharides and its influence on the histological variables of the large intestinal mucosa.

    PubMed

    Tsukahara, Takamitsu; Iwasaki, Yoshie; Nakayama, Keizo; Ushida, Kazunari

    2003-12-01

    Fructooligosaccharides (FOS) reach the large intestine and are fermented into short-chain fatty acids (SCFA), lactate, and carbon dioxide. As the major energy source for the epithelial cells of the large intestine, n-butyrate stimulates the proliferation of cells as well as mineral and water absorption from the lumen. We examined the effect of dietary FOS supplementation on luminal SCFA production and its influence on the morphometrical variables of mucosa of the large intestine in commercially available pigs. Six weaning piglets were used. After 7 d of adaptation, three pigs were given a test diet containing FOS (10%) ad libitum for 10 d. The other three remained on the basal diet and were used as controls. At the end of the experiment, their large intestines were removed, and the cecum, gyri centripetales, gyri centrifugales, and rectum were separated. The contents of each portion were collected and measured for SCFA concentration, pH, and moisture. A micrometer was used to measure the crypt depth. The numbers of epithelial and mitotic cells in the crypt columns were also counted. The concentration of SCFA was significantly higher in piglets fed FOS than in the controls. The concentration of n-butyrate was markedly stimulated by FOS. The number of epithelial. mitotic, and mucin-containing cells was higher in piglets fed FOS than in the controls. Accordingly, the crypt depth was larger in the FOS-fed piglets. The luminal n-butyrate concentration showed a significantly positive correlation with the crypt depth and the number of epithelial, mitotic, and mucin-containing cells.

  3. Effect of hypokinesia on invertase activity of the mucosa of the small intestine

    NASA Technical Reports Server (NTRS)

    Abdusattarov, A.

    1980-01-01

    The effect of prolonged hypokinesia on the enzyme activity of the middle portion of the small intestine was investigated. Eighty-four mongrel white male rats weighing 170-180 g were divided into two equal groups. The experimental group were maintained in single cages under 30 days of hypokinetic conditions and the control animals were maintained under ordinary laboratory conditions. It is concluded that rates of invertase formation and its inclusion in the composition if the cellular membrane, if judged by the enzyme activity studied in sections of the small intestine, are subject to phase changes in the course of prolonged hypokinesia.

  4. Enteric Pathogens and Their Toxin-Induced Disruption of the Intestinal Barrier through Alteration of Tight Junctions in Chickens

    PubMed Central

    Awad, Wageha A.; Hess, Claudia; Hess, Michael

    2017-01-01

    Maintaining a healthy gut environment is a prerequisite for sustainable animal production. The gut plays a key role in the digestion and absorption of nutrients and constitutes an initial organ exposed to external factors influencing bird’s health. The intestinal epithelial barrier serves as the first line of defense between the host and the luminal environment. It consists of a continuous monolayer of intestinal epithelial cells connected by intercellular junctional complexes which shrink the space between adjacent cells. Consequently, free passing of solutes and water via the paracellular pathway is prevented. Tight junctions (TJs) are multi-protein complexes which are crucial for the integrity and function of the epithelial barrier as they not only link cells but also form channels allowing permeation between cells, resulting in epithelial surfaces of different tightness. Tight junction’s molecular composition, ultrastructure, and function are regulated differently with regard to physiological and pathological stimuli. Both in vivo and in vitro studies suggest that reduced tight junction integrity greatly results in a condition commonly known as “leaky gut”. A loss of barrier integrity allows the translocation of luminal antigens (microbes, toxins) via the mucosa to access the whole body which are normally excluded and subsequently destroys the gut mucosal homeostasis, coinciding with an increased susceptibility to systemic infection, chronic inflammation and malabsorption. There is considerable evidence that the intestinal barrier dysfunction is an important factor contributing to the pathogenicity of some enteric bacteria. It has been shown that some enteric pathogens can induce permeability defects in gut epithelia by altering tight junction proteins, mediated by their toxins. Resolving the strategies that microorganisms use to hijack the functions of tight junctions is important for our understanding of microbial pathogenesis, because some pathogens

  5. Enteric Pathogens and Their Toxin-Induced Disruption of the Intestinal Barrier through Alteration of Tight Junctions in Chickens.

    PubMed

    Awad, Wageha A; Hess, Claudia; Hess, Michael

    2017-02-10

    Maintaining a healthy gut environment is a prerequisite for sustainable animal production. The gut plays a key role in the digestion and absorption of nutrients and constitutes an initial organ exposed to external factors influencing bird's health. The intestinal epithelial barrier serves as the first line of defense between the host and the luminal environment. It consists of a continuous monolayer of intestinal epithelial cells connected by intercellular junctional complexes which shrink the space between adjacent cells. Consequently, free passing of solutes and water via the paracellular pathway is prevented. Tight junctions (TJs) are multi-protein complexes which are crucial for the integrity and function of the epithelial barrier as they not only link cells but also form channels allowing permeation between cells, resulting in epithelial surfaces of different tightness. Tight junction's molecular composition, ultrastructure, and function are regulated differently with regard to physiological and pathological stimuli. Both in vivo and in vitro studies suggest that reduced tight junction integrity greatly results in a condition commonly known as "leaky gut". A loss of barrier integrity allows the translocation of luminal antigens (microbes, toxins) via the mucosa to access the whole body which are normally excluded and subsequently destroys the gut mucosal homeostasis, coinciding with an increased susceptibility to systemic infection, chronic inflammation and malabsorption. There is considerable evidence that the intestinal barrier dysfunction is an important factor contributing to the pathogenicity of some enteric bacteria. It has been shown that some enteric pathogens can induce permeability defects in gut epithelia by altering tight junction proteins, mediated by their toxins. Resolving the strategies that microorganisms use to hijack the functions of tight junctions is important for our understanding of microbial pathogenesis, because some pathogens can

  6. Berberine Attenuates Intestinal Mucosal Barrier Dysfunction in Type 2 Diabetic Rats.

    PubMed

    Gong, Jing; Hu, Meilin; Huang, Zhaoyi; Fang, Ke; Wang, Dingkun; Chen, Qingjie; Li, Jingbin; Yang, Desen; Zou, Xin; Xu, Lijun; Wang, Kaifu; Dong, Hui; Lu, Fuer

    2017-01-01

    Background: Intestinal mucosal barrier dysfunction plays an important role in the development of diabetes mellitus (DM). Berberine (BBR), a kind of isoquinoline alkaloid, is widely known to be effective for both DM and diarrhea. Here, we explored whether the anti-diabetic effect of BBR was related to the intestine mucosal barrier. Methods and Results: The rat model of T2DM was established by high glucose and fat diet feeding and intravenous injection of streptozocin. Then, those diabetic rats were treated with BBR at different concentrations for 9 weeks. The results showed, in addition to hyperglycemia and hyperlipidemia, diabetic rats were also characterized by proinflammatory intestinal changes, altered gut-derived hormones, and 2.77-fold increase in intestinal permeability. However, the treatment with BBR significantly reversed the above changes in diabetic rats, presenting as the improvement of the high glucose and triglyceride levels, the relief of the inflammatory changes of intestinal immune system, and the attenuation of the intestinal barrier damage. BBR treatment at a high concentration also decreased the intestinal permeability by 27.5% in diabetic rats. Furthermore, BBR regulated the expressions of the molecules involved in TLR4/MyD88/NF-κB signaling pathways in intestinal tissue of diabetic rats. Conclusion: The hypoglycemic effects of BBR might be related to the improvement in gut-derived hormones and the attenuation of intestinal mucosal mechanic and immune barrier damages.

  7. Berberine Attenuates Intestinal Mucosal Barrier Dysfunction in Type 2 Diabetic Rats

    PubMed Central

    Gong, Jing; Hu, Meilin; Huang, Zhaoyi; Fang, Ke; Wang, Dingkun; Chen, Qingjie; Li, Jingbin; Yang, Desen; Zou, Xin; Xu, Lijun; Wang, Kaifu; Dong, Hui; Lu, Fuer

    2017-01-01

    Background: Intestinal mucosal barrier dysfunction plays an important role in the development of diabetes mellitus (DM). Berberine (BBR), a kind of isoquinoline alkaloid, is widely known to be effective for both DM and diarrhea. Here, we explored whether the anti-diabetic effect of BBR was related to the intestine mucosal barrier. Methods and Results: The rat model of T2DM was established by high glucose and fat diet feeding and intravenous injection of streptozocin. Then, those diabetic rats were treated with BBR at different concentrations for 9 weeks. The results showed, in addition to hyperglycemia and hyperlipidemia, diabetic rats were also characterized by proinflammatory intestinal changes, altered gut-derived hormones, and 2.77-fold increase in intestinal permeability. However, the treatment with BBR significantly reversed the above changes in diabetic rats, presenting as the improvement of the high glucose and triglyceride levels, the relief of the inflammatory changes of intestinal immune system, and the attenuation of the intestinal barrier damage. BBR treatment at a high concentration also decreased the intestinal permeability by 27.5% in diabetic rats. Furthermore, BBR regulated the expressions of the molecules involved in TLR4/MyD88/NF-κB signaling pathways in intestinal tissue of diabetic rats. Conclusion: The hypoglycemic effects of BBR might be related to the improvement in gut-derived hormones and the attenuation of intestinal mucosal mechanic and immune barrier damages. PMID:28217099

  8. Intestinal epithelial cell apoptosis and loss of barrier function in the setting of altered microbiota with enteral nutrient deprivation

    PubMed Central

    Demehri, Farokh R.; Barrett, Meredith; Ralls, Matthew W.; Miyasaka, Eiichi A.; Feng, Yongjia; Teitelbaum, Daniel H.

    2013-01-01

    Total parenteral nutrition (TPN), a commonly used treatment for patients who cannot receive enteral nutrition, is associated with significant septic complications due in part to a loss of epithelial barrier function (EBF). While the underlying mechanisms of TPN-related epithelial changes are poorly understood, a mouse model of TPN-dependence has helped identify several contributing factors. Enteral deprivation leads to a shift in intestinal microbiota to predominantly Gram-negative Proteobacteria. This is associated with an increase in expression of proinflammatory cytokines within the mucosa, including interferon-γ and tumor necrosis factor-α. A concomitant loss of epithelial growth factors leads to a decrease in epithelial cell proliferation and increased apoptosis. The resulting loss of epithelial tight junction proteins contributes to EBF dysfunction. These mechanisms identify potential strategies of protecting against TPN-related complications, such as modification of luminal bacteria, blockade of proinflammatory cytokines, or growth factor replacement. PMID:24392360

  9. Elevated IL-23R Expression and Foxp3+Rorgt+ Cells in Intestinal Mucosa During Acute and Chronic Colitis.

    PubMed

    Yang, Jiayin; Xu, Lili

    2016-08-08

    BACKGROUND IL-23/IL-23R signaling plays a pivotal role during the course of inflammatory bowel diseases (IBD). However, the underlying mechanisms are poorly characterized. Foxp3+ regulatory T cells are critical in the maintenance of gut immune homeostasis and therefore are important in preventing the development of IBD. This study was performed to clarify the association between IL-23/IL-23R signaling and Foxp3+ regulatory T cells in colitis. MATERIAL AND METHODS Acute and chronic mouse colitis models were established by administering mice DSS in drinking water. IL-23R, IL-23, IL-I7, and IFN-γ expression level, as well as regulatory T cell, Th17-, and Th1-related transcription factors Foxp3, RORgt, and T-bet were assayed by real-time PCR. The frequency of Foxp3+ RORγt+ cells in a Foxp3+ cell population in colon mucosa during acute and chronic colitis was evaluated through flow cytometry. The signaling pathway mediated by IL-23R in the colon mucosa from acute colitis mice and chronic colitis mice was monitored by Western blot analysis. RESULTS We detected elevated IL-23R, IL-23, and IFN-γ expression in colon mucosa during acute and chronic colitis and found increased IL-17 in acute colitis mice. Transcription factors Foxp3 and T-bet were elevated in colon mucosa during acute and chronic colitis. Phosphorylation of Stat3 was greatly enhanced, indicating the activation of IL-23R function in colitis mice. The percentage of Foxp3+ T cells in acute and chronic colitis mice was comparable to control mice, but there was a 2-fold increase of Foxp3+ RORγt+ cells among the Foxp3+ cell population in acute and chronic colitis mice compared to control mice. CONCLUSIONS These findings indicate that the induction of Foxp3+ RORgt+ T cells could be enhanced during inflammation in the intestine where IL-23R expression is greatly induced. Our study highlights the importance of IL-23R expression level and the instability of Foxp3+ regulatory T cells in the development of

  10. Effect of level of alimentation on visceral organ mass and the morphology and Na+, K+ adenosinetriphosphatase activity of intestinal mucosa in lambs.

    PubMed

    Rompala, R E; Hoagland, T A

    1987-10-01

    Changes in ovine visceral organ mass and small intestinal mucosa morphology and metabolism due to short-term and prolonged modifications in level of alimentation were studied. Thirty-six lambs were fed for 21 d at either 100 or 50% ad libitum levels of intake. For the next 5 d, lambs either remained on the same intake levels or were switched from 100 or 50% or from 50 to 100% ad libitum intake levels and were subsequently slaughtered. Levels of alimentation the last 5 d before slaughter had a significant effect on weights of the large intestine, small intestine, stomach complex and liver, while only the weight of the liver was affected by 21-d adaptation period. Weights of the heart, lungs, carcass and visceral fat were not affected by level of alimentation. Villus height and mucosal mass at a constant intestinal tissue weight were modified by level of alimentation 5 d before slaughter but static to the previous 21-d nutritional plane. Activity of Na+, K+ ATPase of jejunal mucosa was not influenced by level of alimentation 5 d before slaughter, but was influenced by 21-d adapted level of alimentation. Results from this study are interpreted to indicate that weights of the liver and alimentary tract and small intestinal mucosa development are highly sensitive to changes in level of alimentation.

  11. Enzymatic conversion of all-trans-. beta. -carotene to retinal by a cytosolic enzyme from rabbit and rat intestinal mucosa

    SciTech Connect

    Lakshman, M.R.; Mychkovsky, I.; Attlesey, M. )

    1989-12-01

    Enzymatic conversion of all-trans-{beta}-carotene to retinal by a partially purified enzyme from rabbit and rat intestinal mucosa was demonstrated. The enzymatic product was characterized based on the following evidence: (i) the product gave rise to its O-ethyloxime by treatment with O-ethylhydroxylamine with an absorption maximum at 363 nm in ethanol characteristics of authentic retinal O-ethyloxime. High-pressure liquid chromatography (HPLC) of this derivative yielded a sharp peak with a retention time of 7.99 min corresponding to the authentic compound; (ii) the mass spectrum of the O-ethyloxime of the enzymatic product was identical to that of authentic retinal O-ethyloxime; (iii) the specific activity of the enzymatically formed ({sup 14}C)retinal O-ethyloxime remained constant even after repeated crystallization; (iv) the enzymatic product exhibited an absorption maximum at 370 nm in light petroleum characteristic of authentic retinal. This retinol was enzymatically esterified to retinyl palmitate by rat pancreatic esterase with a retention time of 10 min on HPLC corresponding to authentic retinyl palmitate. Thus, the enzymatic product of {beta}-carotene cleavage by the partially purified intestinal enzyme was unequivocally confirmed to be retinal.

  12. Propionate Ameliorates Dextran Sodium Sulfate-Induced Colitis by Improving Intestinal Barrier Function and Reducing Inflammation and Oxidative Stress

    PubMed Central

    Tong, Ling-chang; Wang, Yue; Wang, Zhi-bin; Liu, Wei-ye; Sun, Sheng; Li, Ling; Su, Ding-feng; Zhang, Li-chao

    2016-01-01

    Propionate is a short chain fatty acid that is abundant as butyrate in the gut and blood. However, propionate has not been studied as extensively as butyrate in the treatment of colitis. The present study was to investigate the effects of sodium propionate on intestinal barrier function, inflammation and oxidative stress in dextran sulfate sodium (DSS)-induced colitis mice. Animals in DSS group received drinking water from 1 to 6 days and DSS [3% (w/v) dissolved in double distilled water] instead of drinking water from 7 to 14 days. Animals in DSS+propionate (DSS+Prop) group were given 1% sodium propionate for 14 consecutive days and supplemented with 3% DSS solution on day 7–14. Intestinal barrier function, proinflammatory factors, oxidative stress, and signal transducer and activator of transcription 3 (STAT3) signaling pathway in the colon were determined. It was found that sodium propionate ameliorated body weight loss, colon-length shortening and colonic damage in colitis mice. Sodium propionate significantly inhibited the increase of FITC-dextran in serum and the decrease of zonula occludens-1 (ZO-1), occludin, and E-cadherin expression in the colonic tissue. It also inhibited the expression of interleukin (IL)-1β, IL-6, and tumor necrosis factor-α (TNF-α) mRNA and phosphorylation of STAT3 in colitis mice markedly, reduced the myeloperoxidase (MPO) level, and increased the superoxide dismutase and catalase level in colon and serum compared with DSS group. Sodium propionate inhibited macrophages with CD68 marker infiltration into the colonic mucosa of colitis mice. These results suggest that oral administration of sodium propionate could ameliorate DSS-induced colitis mainly by improving intestinal barrier function and reducing inflammation and oxidative stress via the STAT3 signaling pathway. PMID:27574508

  13. Curcumin Protects Intestinal Mucosal Barrier Function of Rat Enteritis via Activation of MKP-1 and Attenuation of p38 and NF-κB Activation

    PubMed Central

    Meng, Fan-Su; Zhang, Qing-Hua; Zeng, Jian-Ying; Xiao, Li-Ping; Yu, Xin-Pei; Peng, Dan-dan; Su, Lei; Xiao, Bing; Zhang, Zhen-Shu

    2010-01-01

    Background Intestinal mucosa barrier (IMB) dysfunction results in many notorious diseases for which there are currently few effective treatments. We studied curcumin's protective effect on IMB and examined its mechanism by using methotrexate (MTX) induced rat enteritis model and lipopolysaccharide (LPS) treated cell death model. Methodology/Principal Findings Curcumin was intragastrically administrated from the first day, models were made for 7 days. Cells were treated with curcumin for 30 min before exposure to LPS. Rat intestinal mucosa was collected for evaluation of pathological changes. We detected the activities of D-lactate and diamine oxidase (DAO) according to previous research and measured the levels of myeloperoxidase (MPO) and superoxide dismutase (SOD) by colorimetric method. Intercellular adhesion molecule-1 (ICAM-1), tumor necrosis factor α (TNF-α) and interleukin 1β (IL-1β) were determined by RT-PCR and IL-10 production was determined by ELISA. We found Curcumin decreased the levels of D-lactate, DAO, MPO, ICAM-1, IL-1β and TNF-α, but increased the levels of IL-10 and SOD in rat models. We further confirmed mitogen-activated protein kinase phosphatase-1 (MKP-1) was activated but phospho-p38 was inhibited by curcumin by western blot assay. Finally, NF-κB translocation was monitored by immunofluorescent staining. We showed that curcumin repressed I-κB and interfered with the translocation of NF-κB into nucleus. Conclusions/Significance The effect of curcumin is mediated by the MKP-1-dependent inactivation of p38 and inhibition of NF-κB-mediated transcription. Curcumin, with anti-inflammatory and anti-oxidant activities may be used as an effective reagent for protecting intestinal mucosa barrier and other related intestinal diseases. PMID:20885979

  14. Bacillus cereus var. toyoi promotes growth, affects the histological organization and microbiota of the intestinal mucosa in rainbow trout fingerlings.

    PubMed

    Gisbert, E; Castillo, M; Skalli, A; Andree, K B; Badiola, I

    2013-06-01

    In this preliminary study, we evaluated the effects of a gram-positive soil bacteria Bacillus cereus var. toyoi on the growth performance, digestive enzyme activities, intestinal morphology, and microbiota in rainbow trout Oncorhynchus mykiss fingerlings. Trout were maintained in a recirculation system and fed 2 diets: 1) a commercial trout feed deprived of the probiotic and 2) the same diet but with the spores of the probiotic bacteria dissolved in fish oil during the manufacturing of the feed (final concentration = 2 × 10(4) cfu/g). Each diet was tested in three 400-L cylindroconical tanks (125 fish per tank; initial density = 1.3 kg/m(3); 13.2°C) for a period of 93 d. The probiotic-supplemented diet promoted growth, and the final mean BW and standard length in fish fed the probiotic were 3.4% and 2.1%, respectively, which was greater than the control group (P < 0.05). Fish fed the probiotic showed a more homogeneous distribution in the final BW, with a greater frequency of individuals around the modal of the normal distribution of the population. This result is of practical importance because homogenous production lots can improve rearing practices, reducing hierarchical dominance situations arising from individuals of larger sizes. In addition, the probiotic-supplemented diet increased the level of leukocyte infiltration in the lamina propria of the intestinal mucosa, the number of goblet cells (P < 0.010), and villi height (P < 0.001) but did not affect villi width. The administration of the probiotic changed the intestinal microbiota as indicated by 16S rDNA PCR-restriction fragment length polymorphism. In this sense, fish fed the probiotic formed a well-defined cluster composed of 1 super clade, whereas compared control fish had a greater degree of diversity in their gut microbiota. These changes in gut microbiota did not affect the specific activity of selected pancreatic and intestinal digestive enzymes. These results indicate that the inclusion of the

  15. Supplemental glycine and threonine effects on performance, intestinal mucosa development, and nutrient utilization of growing broiler chickens.

    PubMed

    Ospina-Rojas, I C; Murakami, A E; Oliveira, C A L; Guerra, A F Q G

    2013-10-01

    A study was conducted to evaluate Gly requirements in low-CP diets with different levels of digestible (dig) Thr, and their effects on performance, intestinal mucosal development, and nutrient utilization of broiler chickens from 21 to 35 d age. A total of 240 twenty-one-day-old Cobb-Vantress male broiler chickens were distributed in a completely randomized 4 × 2 factorial arrangement for a total of 8 treatments with 5 replicates of 6 birds each. The treatments consisted of 4 levels of Gly+Ser (1.47, 1.57, 1.67, or 1.77%) and 2 levels of dig Thr (0.70 or 0.77%, corresponding to 100 or 110% of Thr requirements, respectively). Common diets were fed to broilers until 20 d of age. At d 35, an interaction (P ≤ 0.01) was observed between the Gly+Ser and dig Thr levels for G:F. Glycine supplementation resulted in a linear increase (P < 0.05) in BW gain, G:F, intestinal mucin secretion, apparent digestibility of fat, and AME values of the experimental diets. Threonine levels greater than the levels required (0.77%) improved (P < 0.05) G:F and increased (P < 0.05) intestinal mucin secretion. However, intestinal morphometry and the number of goblet cells in the duodenum, jejunum, and ileum were not affected by the treatments. The dietary Gly+Ser level necessary to optimize G:F in low-CP diets containing 0.77% Thr for broiler chickens during growth was estimated to be 1.54%; however, this requirement may be greater than 1.77% in diets with 0.70% Thr. Supplemental Gly may be essential to support maximum performance for broiler chickens from 21 to 35 d of age when they are fed diets based exclusively on vegetable ingredients and with low protein levels. Glycine can directly or indirectly influence the proper function of the intestinal mucosa and improve dietary energy utilization.

  16. Intestinal Epithelial Barrier Disruption through Altered Mucosal MicroRNA Expression in Human Immunodeficiency Virus and Simian Immunodeficiency Virus Infections

    PubMed Central

    Gaulke, Christopher A.; Porter, Matthew; Han, Yan-Hong; Sankaran-Walters, Sumathi; Grishina, Irina; George, Michael D.; Dang, Angeline T.; Ding, Shou-Wei; Jiang, Guochun; Korf, Ian

    2014-01-01

    ABSTRACT Epithelial barrier dysfunction during human immunodeficiency virus (HIV) infection has largely been attributed to the rapid and severe depletion of CD4+ T cells in the gastrointestinal (GI) tract. Although it is known that changes in mucosal gene expression contribute to intestinal enteropathy, the role of small noncoding RNAs, specifically microRNA (miRNA), has not been investigated. Using the simian immunodeficiency virus (SIV)-infected nonhuman primate model of HIV pathogenesis, we investigated the effect of viral infection on miRNA expression in intestinal mucosa. SIV infection led to a striking decrease in the expression of mucosal miRNA compared to that in uninfected controls. This decrease coincided with an increase in 5′-3′-exoribonuclease 2 protein and alterations in DICER1 and Argonaute 2 expression. Targets of depleted miRNA belonged to molecular pathways involved in epithelial proliferation, differentiation, and immune response. Decreased expression of several miRNA involved in maintaining epithelial homeostasis in the gut was localized to the proliferative crypt region of the intestinal epithelium. Our findings suggest that SIV-induced decreased expression of miRNA involved in epithelial homeostasis, disrupted expression of miRNA biogenesis machinery, and increased expression of XRN2 are involved in the development of epithelial barrier dysfunction and gastroenteropathy. IMPORTANCE MicroRNA (miRNA) regulate the development and function of intestinal epithelial cells, and many viruses disrupt normal host miRNA expression. In this study, we demonstrate that SIV and HIV disrupt expression of miRNA in the small intestine during infection. The depletion of several key miRNA is localized to the proliferative crypt region of the gut epithelium. These miRNA are known to control expression of genes involved in inflammation, cell death, and epithelial maturation. Our data indicate that this disruption might be caused by altered expression of mi

  17. Cardiolipins Act as a Selective Barrier to Toll-Like Receptor 4 Activation in the Intestine

    PubMed Central

    Coats, Stephen R.; Hashim, Ahmed; Paramonov, Nikolay A.; Curtis, Michael A.

    2016-01-01

    ABSTRACT Intestinal homeostasis mechanisms must protect the host intestinal tissue from endogenous lipopolysaccharides (LPSs) produced by the intestinal microbiota. In this report, we demonstrate that murine intestinal fecal lipids effectively block Toll-like receptor 4 (TLR4) responses to naturally occurring Bacteroidetes sp. LPS. Cardiolipin (CL) represents a significant proportion of the total intestinal and fecal lipids and, furthermore, potently antagonizes TLR4 activation by reducing LPS binding at the lipopolysaccharide binding protein (LBP), CD14, and MD-2 steps of the TLR4 signaling pathway. It is further demonstrated that intestinal lipids and CL are less effective at neutralizing more potent Enterobacteriaceae-type LPS, which is enriched in feces obtained from mice with dextran sodium sulfate (DSS)-treated inflammatory bowel disease. The selective inhibition of naturally occurring LPS structures by intestinal lipids may represent a novel homeostasis mechanism that blocks LPS activation in response to symbiotic but not dysbiotic microbial communities. IMPORTANCE The guts of animals harbor a variety of Gram-negative bacteria associated with both states of intestinal health and states of disease. Environmental factors, such as dietary habits, can drive the microbial composition of the host animal's intestinal bacterial community toward a more pathogenic state. Both beneficial and harmful Gram-negative bacteria are capable of eliciting potentially damaging inflammatory responses from the host intestinal tissues via a lipopolysaccharide (LPS)-dependent pathway. Physical mucosal barriers and antibodies produced by the intestinal immune system protect against the undesired inflammatory effects of LPS, although it is unknown why some bacteria are more effective at overcoming the protective barriers than others. This report describes the discovery of a lipid-type protective barrier in the intestine that reduces the deleterious effects of LPSs from beneficial

  18. Potential benefits of pro- and prebiotics on intestinal mucosal immunity and intestinal barrier in short bowel syndrome.

    PubMed

    Stoidis, Christos N; Misiakos, Evangelos P; Patapis, Paul; Fotiadis, Constantine I; Spyropoulos, Basileios G

    2011-06-01

    The mechanism of impaired gut barrier function in patients with short bowel syndrome (SBS) is poorly understood and includes decreased intestinal motility leading to bacterial overgrowth, a reduction in gut-associated lymphoid tissue following the loss of intestinal length, inhibition of mucosal immunity of the small intestine by intravenous total parental nutrition, and changes in intestinal permeability to macromolecules. Novel therapeutic strategies (i.e. nutritive and surgical) have been introduced in order to prevent the establishment or improve the outcome of this prevalent disease. Pre- and probiotics as a nutritive supplement are already known to be very active in the intestinal tract (mainly in the colon) by maintaining a healthy gut microflora and influencing metabolic, trophic and protective mechanisms, such as the production of SCFA which influence epithelial cell metabolism, turnover and apoptosis. Probiotics have been recommended for patients suffering from SBS in order to decrease bacterial overgrowth and prevent bacterial translocation, two major mechanisms in the pathogenesis of SBS. The present review discusses the research available in the international literature, clinical and experimental, regarding probiotic supplementation for this complicated group of patients based on the clinical spectrum and pathophysiological aspects of the syndrome. The clinical data that were collected for the purposes of the present review suggest that it is difficult to correctly characterise probiotics as a preventive or therapeutic measure. It is very challenging after all to examine the relationship of the bacterial flora, the intestinal barrier and the probiotics as, according to the latest knowledge, demonstrate an interesting interaction.

  19. ClC-2 regulation of intestinal barrier function: Translation of basic science to therapeutic target.

    PubMed

    Jin, Younggeon; Blikslager, Anthony T

    2015-01-01

    The ClC-2 chloride channel is a member of the voltage-gated chloride channel family. ClC-2 is involved in various physiological processes, including fluid transport and secretion, regulation of cell volume and pH, maintaining the membrane potential of the cell, cell-to-cell communication, and tissue homeostasis. Recently, our laboratory has accumulated evidence indicating a critical role of ClC-2 in the regulation of intestinal barrier function by altering inter-epithelial tight junction composition. This review will detail the role of ClC-2 in intestinal barrier function during intestinal disorders, including experimental ischemia/reperfusion injury and dextran sodium sulfate (DSS)-induced inflammatory bowel disease. Details of pharmacological manipulation of ClC-2 via prostone agonists will also be provided in an effort to show the potential therapeutic relevance of ClC-2 regulation, particularly during intestinal barrier disruption.

  20. ClC-2 regulation of intestinal barrier function: Translation of basic science to therapeutic target

    PubMed Central

    Jin, Younggeon; Blikslager, Anthony T

    2015-01-01

    The ClC-2 chloride channel is a member of the voltage-gated chloride channel family. ClC-2 is involved in various physiological processes, including fluid transport and secretion, regulation of cell volume and pH, maintaining the membrane potential of the cell, cell-to-cell communication, and tissue homeostasis. Recently, our laboratory has accumulated evidence indicating a critical role of ClC-2 in the regulation of intestinal barrier function by altering inter-epithelial tight junction composition. This review will detail the role of ClC-2 in intestinal barrier function during intestinal disorders, including experimental ischemia/reperfusion injury and dextran sodium sulfate (DSS)-induced inflammatory bowel disease. Details of pharmacological manipulation of ClC-2 via prostone agonists will also be provided in an effort to show the potential therapeutic relevance of ClC-2 regulation, particularly during intestinal barrier disruption. PMID:26716076

  1. Is intestinal inflammation linking dysbiosis to gut barrier dysfunction during liver disease?

    PubMed Central

    Brandl, Katharina

    2016-01-01

    Changes in the intestinal microbiota composition contribute to the pathogenesis of many disorders including gastrointestinal and liver diseases. Recent studies have broadened our understanding of the “gut-liver” axis. Dietary changes, other environmental and genetic factors can lead to alterations in the microbiota. Dysbiosis can further disrupt the integrity of the intestinal barrier leading to pathological bacterial translocation and the initiation of an inflammatory response in the liver. In this article, the authors dissect the different steps involved in disease pathogenesis to further refine approaches for the medical management of liver diseases. The authors will specifically discuss the role of dysbiosis in inducing intestinal inflammation and increasing intestinal permeability. PMID:26088524

  2. Development of a Multicellular Three-dimensional Organotypic Model of the Human Intestinal Mucosa Grown Under Microgravity.

    PubMed

    Salerno-Goncalves, Rosangela; Fasano, Alessio; Sztein, Marcelo B

    2016-07-25

    Because cells growing in a three-dimensional (3-D) environment have the potential to bridge many gaps of cell cultivation in 2-D environments (e.g., flasks or dishes). In fact, it is widely recognized that cells grown in flasks or dishes tend to de-differentiate and lose specialized features of the tissues from which they were derived. Currently, there are mainly two types of 3-D culture systems where the cells are seeded into scaffolds mimicking the native extracellular matrix (ECM): (a) static models and (b) models using bioreactors. The first breakthrough was the static 3-D models. 3-D models using bioreactors such as the rotating-wall-vessel (RWV) bioreactors are a more recent development. The original concept of the RWV bioreactors was developed at NASA's Johnson Space Center in the early 1990s and is believed to overcome the limitations of static models such as the development of hypoxic, necrotic cores. The RWV bioreactors might circumvent this problem by providing fluid dynamics that allow the efficient diffusion of nutrients and oxygen. These bioreactors consist of a rotator base that serves to support and rotate two different formats of culture vessels that differ by their aeration source type: (1) Slow Turning Lateral Vessels (STLVs) with a co-axial oxygenator in the center, or (2) High Aspect Ratio Vessels (HARVs) with oxygenation via a flat, silicone rubber gas transfer membrane. These vessels allow efficient gas transfer while avoiding bubble formation and consequent turbulence. These conditions result in laminar flow and minimal shear force that models reduced gravity (microgravity) inside the culture vessel. Here we describe the development of a multicellular 3-D organotypic model of the human intestinal mucosa composed of an intestinal epithelial cell line and primary human lymphocytes, endothelial cells and fibroblasts cultured under microgravity provided by the RWV bioreactor.

  3. Adenosine A2B receptor modulates intestinal barrier function under hypoxic and ischemia/reperfusion conditions

    PubMed Central

    Yang, Yang; Qiu, Yuan; Wang, Wensheng; Xiao, Weidong; Liang, Hongyin; Zhang, Chaojun; Yang, Hanwenbo; Teitelbaum, Daniel H; Sun, Li-Hua; Yang, Hua

    2014-01-01

    Background: Intestinal barrier function failure from ischemia/reperfusion (I/R) and acute hypoxia has been implicated as a critical determinant in the predisposition to intestinal inflammation and a number of inflammatory disorders. Here, we identified the role of Adenosine A2B receptor (A2BAR) in the regulation of intestinal barrier function under I/R and acute hypoxic conditions. Methods: C57BL/6J mice were used, and were randomized into three groups: Sham, I/R, IR+PSB1115 (a specific A2BAR antagonist) groups. After surgery, the small bowel was harvested for immunohistochemical staining, RNA and protein content, and intestinal permeability analyses. Using an epithelial cell culture model, we investigated the influence of hypoxia on the epithelial function, and the role of A2BAR in the expressions of tight junction and epithelial permeability. The expressions of Claudin-1, occludin and ZO-1 were detected by RT-PCR and Western-Blot. Epithelial barrier function was assessed with transepithelial resistance (TER). Results and conclusions: The A2BAR antagonist, PSB1115, significantly increased tight junction protein expression after intestinal I/R or acute hypoxia conditions. PSB1115 also attenuated the disrupted distribution of TJ proteins. Furthermore, inhibition of A2BAR attenuated the decrease in TER induced by I/R or acute hypoxic conditions, and maintained intestinal barrier function. Antagonism of A2BAR activity improves intestinal epithelial structure and barrier function in a mouse model of intestinal I/R and a cell model of acute hypoxia. These findings support a potentially destructive role for A2BAR under intestinal I/R and acute hypoxic conditions. PMID:24966910

  4. Femtosecond laser ablation of porcine intestinal mucosa: potential autologous transplant for segmental cystectomy

    NASA Astrophysics Data System (ADS)

    Higbee, Russell G.; Irwin, Bryan S.; Nguyen, Michael N.; Zhang, Yuanyuan; Warren, William L.

    2005-04-01

    Nearly 80% of patients with newly diagnosed bladder cancer present with superficial bladder tumors (confined to the bladder lining such as transitional cell carcinoma [90%], squamous cell carcinoma [6-8%], and adenocarcinoma[2%]) in stages Ta, Tis, or T1. Segmental cystectomy is one surgical treatment for patients who have a low-grade invasive tumor. Transposition of small intestine is a viable surgical treatment option. Success of the transplantation is also dependent upon removal of the entire SI mucosal layer. A Clark Spitfire Ti:Sapphire laser operating at 775 nm and 1 kHz repetition rate, was used to investigate the damage induced to fresh cadaveric porcine small intestinal mucosal epithelium. The laser was held constant at a focal spot diameter of 100 μm using a 200 mm focal point lens, with a power output maximum of 257 mW. A high resolution motorized X-Y-Z stage translated the SI tissue through the beam at 500 μm/sec with a line spacing of 50 μm. This produced a 50% overlap in the laser etching for each pass over a 1 cm x 1.5 cm grid. To determine if the mucosal lining of the SI was adequately removed, the targeted area was covered with 1% fluorescein solution for 30 seconds and then rinsed with phosphate buffered saline. Fluorescein staining was examined under UV illumination, to determine the initial degree of mucosal removal. Tissues were fixed and processed for light and scanning electron microscopy by standard protocols. Brightfield light microscopy of hematoxylin and eosin stained 4 μm thick cross sections, scanning electron microscopy were examined to determine the degree of mucosal tissue removal. Clear delineation of the submucosal layer by fluorescein staining was also observed. The Ti:Sapphire laser demonstrated precise, efficient removal of the mucosal epithelium with minimal submucosal damage.

  5. Gluten affects epithelial differentiation-associated genes in small intestinal mucosa of coeliac patients.

    PubMed

    Juuti-Uusitalo, K; Mäki, M; Kainulainen, H; Isola, J; Kaukinen, K

    2007-11-01

    In coeliac disease gluten induces an immunological reaction in genetically susceptible patients, and influences on epithelial cell proliferation and differentiation in the small-bowel mucosa. Our aim was to find novel genes which operate similarly in epithelial proliferation and differentiation in an epithelial cell differentiation model and in coeliac disease patient small-bowel mucosal biopsy samples. The combination of cDNA microarray data originating from a three-dimensional T84 epithelial cell differentiation model and small-bowel mucosal biopsy samples from untreated and treated coeliac disease patients and healthy controls resulted in 30 genes whose mRNA expression was similarly affected. Nine of 30 were located directly or indirectly in the receptor tyrosine kinase pathway starting from the epithelial growth factor receptor. Removal of gluten from the diet resulted in a reversion in the expression of 29 of the 30 genes in the small-bowel mucosal biopsy samples. Further characterization by blotting and labelling revealed increased epidermal growth factor receptor and beta-catenin protein expression in the small-bowel mucosal epithelium in untreated coeliac disease patients compared to healthy controls and treated coeliac patients. We found 30 genes whose mRNA expression was affected similarly in the epithelial cell differentiation model and in the coeliac disease patient small-bowel mucosal biopsy samples. In particular, those genes involved in the epithelial growth factor-mediated signalling pathways may be involved in epithelial cell differentiation and coeliac disease pathogenesis. The epithelial cell differentiation model is a useful tool for studying gene expression changes in the crypt-villus axis.

  6. Expression of the Na+/l- symporter (NIS) is markedly decreased or absent in gastric cancer and intestinal metaplastic mucosa of Barrett esophagus

    PubMed Central

    Altorjay, Áron; Dohán, Orsolya; Szilágyi, Anna; Paroder, Monika; Wapnir, Irene L; Carrasco, Nancy

    2007-01-01

    Background The sodium/iodide symporter (NIS) is a plasma membrane glycoprotein that mediates iodide (I-) transport in the thyroid, lactating breast, salivary glands, and stomach. Whereas NIS expression and regulation have been extensively investigated in healthy and neoplastic thyroid and breast tissues, little is known about NIS expression and function along the healthy and diseased gastrointestinal tract. Methods Thus, we investigated NIS expression by immunohistochemical analysis in 155 gastrointestinal tissue samples and by immunoblot analysis in 17 gastric tumors from 83 patients. Results Regarding the healthy Gl tract, we observed NIS expression exclusively in the basolateral region of the gastric mucin-producing epithelial cells. In gastritis, positive NIS staining was observed in these cells both in the presence and absence of Helicobacter pylori. Significantly, NIS expression was absent in gastric cancer, independently of its histological type. Only focal faint NIS expression was detected in the direct vicinity of gastric tumors, i.e., in the histologically intact mucosa, the expression becoming gradually stronger and linear farther away from the tumor. Barrett mucosa with junctional and fundic-type columnar metaplasia displayed positive NIS staining, whereas Barrett mucosa with intestinal metaplasia was negative. NIS staining was also absent in intestinalized gastric polyps. Conclusion That NIS expression is markedly decreased or absent in case of intestinalization or malignant transformation of the gastric mucosa suggests that NIS may prove to be a significant tumor marker in the diagnosis and prognosis of gastric malignancies and also precancerous lesions such as Barrett mucosa, thus extending the medical significance of NIS beyond thyroid disease. PMID:17214887

  7. Expression of the nociceptin/orphanin FQ receptor in the intestinal mucosa of IBS patients

    PubMed Central

    LI, LU; DONG, LEI; WANG, SHENHAO

    2013-01-01

    Nociceptin/orphanin FQ (N/OFQ) and the N/OFQ peptide (NOP) receptor play important roles in regulating gastrointestinal function. To assess whether the NOP receptor is implicated in the etiopathogenesis of irritable bowel syndrome (IBS), we measured the levels of NOP receptor mRNA and protein in the jejunal and colonic tissues of healthy subjects and patients with diarrhea-predominant IBS (D-IBS) and constipation-predominant IBS (C-IBS). Mucosal biopsies were obtained from the jejunum and colon of patients diagnosed with D-IBS and C-IBS by the Rome III criteria and from healthy control subjects. The expression of NOP receptor mRNA was measured quantitatively using quantitative PCR (qPCR) and NOP protein expression was assayed immunohistochemically using a rabbit monoclonal antibody to OFQ. NOP receptor mRNA was detected in the jejunum and colon of healthy subjects and was more highly expressed in the jejunum than in the colon. Expression was lower in the jejunum and colon of patients with D-IBS; however, it was similar in patients with C-IBS and healthy subjects. The numbers of OFQ-positive cells in the jejunum and colon were similar among the three groups. The NOP receptor may be involved in the regulation of intestinal movement in healthy individuals. Its involvement in the pathophysiology of IBS may depend on whether the IBS is constipation- or diarrhea-predominant. PMID:24137246

  8. WISP1 Is Increased in Intestinal Mucosa and Contributes to Inflammatory Cascades in Inflammatory Bowel Disease

    PubMed Central

    Zhang, Qi; Zhang, Cuiping; Li, Xiaoyu; Yu, Yanan; Liang, Kun; Shan, Xinzhi; Zhao, Kun; Niu, Qinghui; Tian, Zibin

    2016-01-01

    Inflammatory bowel disease (IBD) is mainly characterized by intestinal tissue damage, which is caused by excessive autoimmune responses poorly controlled by corresponding regulatory mechanisms. WISP1, which belongs to the CCN protein family, is a secreted matricellular protein regulating several inflammatory pathways, such as Wnt/β-catenin pathway, and has been reported in several diseases including cancer. Here we examined the expression, regulatory mechanisms, and functions of WISP1 in IBD. WISP1 mRNA and protein expression was upregulated in colonic biopsies and lamina propria mononuclear cells (LPMC) of IBD patients compared with those of healthy controls. Tumor necrosis factor- (TNF-) α induced WISP1 expression in LPMC from healthy controls. Consistently, WISP1 mRNA expression was downregulated in colonic biopsies from IBD patients who had achieved clinical remission with infliximab (IFX). Furthermore, WISP1 expression was also found to be increased in colons from 2,4,6-trinitrobenzenesulfonic acid- (TNBS-) induced mice compared with those from control mice. Further studies confirmed that administration of rWISP1 could aggravate TNBS-induced colitis in vivo. Therefore, we concluded that WISP1 is increased in IBD and contributes to the proinflammatory cascades in the gut. PMID:27403031

  9. Expression of the nociceptin/orphanin FQ receptor in the intestinal mucosa of IBS patients.

    PubMed

    Li, Lu; Dong, Lei; Wang, Shenhao

    2013-09-01

    Nociceptin/orphanin FQ (N/OFQ) and the N/OFQ peptide (NOP) receptor play important roles in regulating gastrointestinal function. To assess whether the NOP receptor is implicated in the etiopathogenesis of irritable bowel syndrome (IBS), we measured the levels of NOP receptor mRNA and protein in the jejunal and colonic tissues of healthy subjects and patients with diarrhea-predominant IBS (D-IBS) and constipation-predominant IBS (C-IBS). Mucosal biopsies were obtained from the jejunum and colon of patients diagnosed with D-IBS and C-IBS by the Rome III criteria and from healthy control subjects. The expression of NOP receptor mRNA was measured quantitatively using quantitative PCR (qPCR) and NOP protein expression was assayed immunohistochemically using a rabbit monoclonal antibody to OFQ. NOP receptor mRNA was detected in the jejunum and colon of healthy subjects and was more highly expressed in the jejunum than in the colon. Expression was lower in the jejunum and colon of patients with D-IBS; however, it was similar in patients with C-IBS and healthy subjects. The numbers of OFQ-positive cells in the jejunum and colon were similar among the three groups. The NOP receptor may be involved in the regulation of intestinal movement in healthy individuals. Its involvement in the pathophysiology of IBS may depend on whether the IBS is constipation- or diarrhea-predominant.

  10. Effects of orlistat and its relationship with nitric oxide in the small intestinal mucosa.

    PubMed

    Caner, Metin; Dogruman, Husniye; Taşkin, Elif; Kandil, Asli; Demirci, Cihan

    2005-12-31

    Nitric oxide (NO) is known to be a messenger molecule that plays an important role in physiological and pathological conditions. It is synthesized by an enzyme called nitric oxide synthase (NOS). Inducible NOS (iNOS), one of the three isomers of NOS, has both protective and toxic properties. In this study, the role of NO has been evaluated by gastrointestinal symptoms induced by orlistat which is used in obesity treatment. Orlistat was given to Wistar rats with and without iNOS inhibition. The effects of orlistat and inhibition of NOS were studied. Glucose, urea, alanine transaminase (ALT), and gamma glutamil transpeptidase (GGT) were descreased after short- and long- term orlistat applications. Dexamethasone increased level of these enzymes. Cholesterol and triglyceride were increased in all experimental groups than the controls. This increment was more severe in animals received orlistat and dexamethasone together. Small intestinal tissue also were researched histologically and NADPH-diaphorase (NADPH-d) histochemistrically. Orlistat caused histological damages in brush border membranes, connective tissues of villi, and lymphocyte migration also increased. Dexamethasone treatment prevented these damages partially while orlistat increased the NOS distribution in the tissue sections. Dexamethasone, which is an iNOS inhibitor, decreased NADPH-d histochemistry. There was a similiar NOS distribution both in the control and orlistat+dexamethasone group. Hence, we concluded that long- term trials with orlistat and similar drugs are needed.

  11. Arctigenin from Fructus Arctii (Seed of Burdock) Reinforces Intestinal Barrier Function in Caco-2 Cell Monolayers.

    PubMed

    Shin, Hee Soon; Jung, Sun Young; Back, Su Yeon; Do, Jeong-Ryong; Shon, Dong-Hwa

    2015-01-01

    Fructus Arctii is used as a traditional herbal medicine to treat inflammatory diseases in oriental countries. This study aimed to investigate effect of F. Arctii extract on intestinal barrier function in human intestinal epithelial Caco-2 cells and to reveal the active component of F. Arctii. We measured transepithelial electrical resistance (TEER) value (as an index of barrier function) and ovalbumin (OVA) permeation (as an index of permeability) to observe the changes of intestinal barrier function. The treatment of F. Arctii increased TEER value and decreased OVA influx on Caco-2 cell monolayers. Furthermore, we found that arctigenin as an active component of F. Arctii increased TEER value and reduced permeability of OVA from apical to the basolateral side but not arctiin. In the present study, we revealed that F. Arctii could enhance intestinal barrier function, and its active component was an arctigenin on the functionality. We expect that the arctigenin from F. Arctii could contribute to prevention of inflammatory, allergic, and infectious diseases by reinforcing intestinal barrier function.

  12. Arctigenin from Fructus Arctii (Seed of Burdock) Reinforces Intestinal Barrier Function in Caco-2 Cell Monolayers

    PubMed Central

    Shin, Hee Soon; Jung, Sun Young; Back, Su Yeon; Do, Jeong-Ryong; Shon, Dong-Hwa

    2015-01-01

    Fructus Arctii is used as a traditional herbal medicine to treat inflammatory diseases in oriental countries. This study aimed to investigate effect of F. Arctii extract on intestinal barrier function in human intestinal epithelial Caco-2 cells and to reveal the active component of F. Arctii. We measured transepithelial electrical resistance (TEER) value (as an index of barrier function) and ovalbumin (OVA) permeation (as an index of permeability) to observe the changes of intestinal barrier function. The treatment of F. Arctii increased TEER value and decreased OVA influx on Caco-2 cell monolayers. Furthermore, we found that arctigenin as an active component of F. Arctii increased TEER value and reduced permeability of OVA from apical to the basolateral side but not arctiin. In the present study, we revealed that F. Arctii could enhance intestinal barrier function, and its active component was an arctigenin on the functionality. We expect that the arctigenin from F. Arctii could contribute to prevention of inflammatory, allergic, and infectious diseases by reinforcing intestinal barrier function. PMID:26550018

  13. The effects of Lactobacillus plantarum on small intestinal barrier function and mucosal gene transcription; a randomized double-blind placebo controlled trial

    PubMed Central

    Mujagic, Zlatan; de Vos, Paul; Boekschoten, Mark V.; Govers, Coen; Pieters, Harm-Jan H. M.; de Wit, Nicole J. W.; Bron, Peter A.; Masclee, Ad A. M.; Troost, Freddy J.

    2017-01-01

    The aim of this study was to investigate the effects of three Lactobacillus plantarum strains on in-vivo small intestinal barrier function and gut mucosal gene transcription in human subjects. The strains were selected for their differential effects on TLR signalling and tight junction protein rearrangement, which may lead to beneficial effects in a stressed human gut mucosa. Ten healthy volunteers participated in four different intervention periods: 7-day oral intake of either L. plantarum WCFS1, CIP104448, TIFN101 or placebo, proceeded by a 4 weeks wash-out period. Lactulose-rhamnose ratio (an indicator of small intestinal permeability) increased after intake of indomethacin, which was given as an artificial stressor of the gut mucosal barrier (mean ratio 0.06 ± 0.04 to 0.10 ± 0.06, p = 0.001), but was not significantly affected by the bacterial interventions. However, analysis in small intestinal biopsies, obtained by gastroduodenoscopy, demonstrated that particularly L. plantarum TIFN101 modulated gene transcription pathways related to cell-cell adhesion with high turnover of genes involved in tight- and adhesion junction protein synthesis and degradation (e.g. actinin alpha-4, metalloproteinase-2). These effects were less pronounced for L. plantarum WCFS1 and CIP104448. In conclusion, L. plantarum TIFN101 induced the most pronounced probiotic properties with specific gene transcriptional effects on repair processes in the compromised intestine of healthy subjects. PMID:28045137

  14. The Tripeptide KdPT Protects from Intestinal Inflammation and Maintains Intestinal Barrier Function

    PubMed Central

    Bettenworth, Dominik; Buyse, Marion; Böhm, Markus; Mennigen, Rudolf; Czorniak, Isabel; Kannengiesser, Klaus; Brzoska, Thomas; Luger, Thomas A.; Kucharzik, Torsten; Domschke, Wolfram; Maaser, Christian; Lügering, Andreas

    2011-01-01

    Treatment options for inflammatory bowel disease (IBD) are incompletely helpful, and surgery is often needed. One promising class of future therapeutic agents for IBD is melanocortin-related peptides, which exhibit potent immunomodulatory effects. We investigated KdPT, a tripeptide derivative of the C-terminus of α–melanocyte-stimulating hormone, as an anti-inflammatory small molecule in vivo and in vitro. Intestinal inflammation was studied after oral administration of dextran sodium sulfate and in IL-10 gene–deficient mice. The effects of KdPT on key colonic epithelial cell functions were studied in vitro and in vivo by evaluating proliferation, wound healing, transepithelial resistance, and expression of tight junction proteins. Melanin assays were performed to determine the melanotropic effects of KdPT. KdPT-treated animals showed markedly reduced severity of inflammation in both colitis models. In colonic epithelial cells, KdPT increased proliferation, accelerated closure of wounds, and improved transepithelial electrical resistance after stimulation with interferon-γ/tumor necrosis factor-α. Moreover, treatment with KdPT also prevented the loss of tight junction protein expression and improved barrier function in vivo. KdPT acted independently of IL-1 receptor type I in vivo and did not affect melanogenesis in vitro. KdPT is capable of attenuating the course of experimental colitis in different models and maintains epithelial cell function. Furthermore, KdPT does not induce pigmentation, emphasizing the potential of this small molecule for the future treatment of IBD. PMID:21741932

  15. Protelytic Regulation of the Intestinal Epithelial Barrier: Mechanisms and Interventions

    DTIC Science & Technology

    2015-09-01

    gene that is required for epithelial barrier homeostasis . The project uses the St14 hypomorphic mouse model of matriptase deficiency to 1) determine...Tumorigenicity-14 (ST14) that is required for epithelial barrier homeostasis . Here, we are investigating matriptase dysregulation and its contribution

  16. Intestinal Barrier Disturbances in Haemodialysis Patients: Mechanisms, Consequences, and Therapeutic Options

    PubMed Central

    Graham-Brown, M. P. M.; Burton, J. O.

    2017-01-01

    There is accumulating evidence that the intestinal barrier and the microbiota may play a role in the systemic inflammation present in HD patients. HD patients are subject to a number of unique factors, some related to the HD process and others simply to the uraemic milieu but with common characteristic that they can both alter the intestinal barrier and the microbiota. This review is intended to provide an overview of the current methods for measuring such changes in HD patients, the mechanisms behind these changes, and potential strategies that may mitigate these modifications. Lastly, intradialytic exercise is an increasingly employed intervention in HD patients; however the potential implications that this may have for the intestinal barrier are not known; therefore future research directions are also covered. PMID:28194419

  17. Lipid rafts are disrupted in mildly inflamed intestinal microenvironments without overt disruption of the epithelial barrier.

    PubMed

    Bowie, Rachel V; Donatello, Simona; Lyes, Clíona; Owens, Mark B; Babina, Irina S; Hudson, Lance; Walsh, Shaun V; O'Donoghue, Diarmuid P; Amu, Sylvie; Barry, Sean P; Fallon, Padraic G; Hopkins, Ann M

    2012-04-15

    Intestinal epithelial barrier disruption is a feature of inflammatory bowel disease (IBD), but whether barrier disruption precedes or merely accompanies inflammation remains controversial. Tight junction (TJ) adhesion complexes control epithelial barrier integrity. Since some TJ proteins reside in cholesterol-enriched regions of the cell membrane termed lipid rafts, we sought to elucidate the relationship between rafts and intestinal epithelial barrier function. Lipid rafts were isolated from Caco-2 intestinal epithelial cells primed with the proinflammatory cytokine interferon-γ (IFN-γ) or treated with methyl-β-cyclodextrin as a positive control for raft disruption. Rafts were also isolated from the ilea of mice in which colitis had been induced in conjunction with in vivo intestinal permeability measurements, and lastly from intestinal biopsies of ulcerative colitis (UC) patients with predominantly mild or quiescent disease. Raft distribution was analyzed by measuring activity of the raft-associated enzyme alkaline phosphatase and by performing Western blot analysis for flotillin-1. Epithelial barrier integrity was estimated by measuring transepithelial resistance in cytokine-treated cells or in vivo permeability to fluorescent dextran in colitic mice. Raft and nonraft fractions were analyzed by Western blotting for the TJ proteins occludin and zonula occludens-1 (ZO-1). Our results revealed that lipid rafts were disrupted in IFN-γ-treated cells, in the ilea of mice with subclinical colitis, and in UC patients with quiescent inflammation. This was not associated with a clear pattern of occludin or ZO-1 relocalization from raft to nonraft fractions. Significantly, a time-course study in colitic mice revealed that disruption of lipid rafts preceded the onset of increased intestinal permeability. Our data suggest for the first time that lipid raft disruption occurs early in the inflammatory cascade in murine and human colitis and, we speculate, may contribute to

  18. Nutritional value of dried fermentation biomass, hydrolyzed porcine intestinal mucosa products, and fish meal fed to weanling pigs.

    PubMed

    Sulabo, R C; Mathai, J K; Usry, J L; Ratliff, B W; McKilligan, D M; Moline, J D; Xu, G; Stein, H H

    2013-06-01

    Dried fermentation biomass (DFB) and hydrolyzed porcine intestinal mucosa are co-products of L-Lys • HCl production and heparin extraction, respectively. Three experiments were conducted to determine standardized ileal digestibility (SID) of AA (Exp. 1), concentration of DE and ME (Exp. 2), and standardized total tract digestibility (STTD) of P (Exp. 3) in DFB and 2 hydrolyzed porcine intestinal mucosa products (PEP50 and PEP2+), and compare these values with values for fish meal. In Exp. 1, 12 ileal cannulated barrows (BW = 11.5 ± 1.1 kg) were allotted to a replicated 6 × 6 Latin square design with 6 diets and 6 periods. A N-free diet, diet based on soybean meal (SBM), and 4 diets based on a combination of SBM and DFB, PEP50, PEP2+, or fish meal were formulated. With the exception of Lys, there were no differences in SID of indispensable AA between DFB and fish meal. Except for Thr, no differences in SID of indispensable AA between PEP50 and fish meal were observed, but SID of all indispensable AA, except Lys and Trp, was less (P < 0.05) in PEP2+ than in the other ingredients. In Exp. 2, 40 barrows (BW = 12.8 ± 1.4 kg) were allotted to 5 diets with 8 pigs/diet. A basal diet containing 96.4% corn and 4 diets containing corn and DFB, PEP50, PEP2+, or fish meal were formulated. The DE (5,445 kcal/kg DM) and ME (5,236 kcal/kg DM) in DFB were greater (P < 0.01) than in PEP50 (4,758 and 4,512 kcal/kg DM for DE and ME, respectively) and fish meal (4,227 and 3,960 kcal/kg DM for DE and ME, respectively). Also, DE in DFB was greater (P < 0.01) than in PEP2+ (4,935 kcal/kg DM), but ME in DFB was not different from that in PEP2+ (4,617 kcal/kg DM). Furthermore, DE in PEP50 and PEP2+ were greater (P < 0.01) than in fish meal, but ME did not differ from that in fish meal. In Exp. 3, 40 barrows (BW = 12.4 ± 1.3 kg) were randomly allotted to 5 diets with 8 pigs/diet. A P-free diet and 4 diets in which the sole source of P was from DFB, PEP50, PEP2+, or fish meal were

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

    SciTech Connect

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

    2009-05-15

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

  20. IL-9 regulates intestinal barrier function in experimental T cell-mediated colitis

    PubMed Central

    Gerlach, Katharina; McKenzie, Andrew N; Neurath, Markus F; Weigmann, Benno

    2015-01-01

    As previous studies suggested that IL-9 may control intestinal barrier function, we tested the role of IL-9 in experimental T cell-mediated colitis induced by the hapten reagent 2,4,6-trinitrobenzenesulfonic acid (TNBS). The deficiency of IL-9 suppressed TNBS-induced colitis and led to lower numbers of PU.1 expressing T cells in the lamia propria, suggesting a regulatory role for Th9 cells in the experimental TNBS colitis model. Since IL-9 is known to functionally alter intestinal barrier function in colonic inflammation, we assessed the expression of tight junction molecules in intestinal epithelial cells of TNBS-inflamed mice. Therefore we made real-time PCR analyses for tight junction molecules in the inflamed colon from wild-type and IL-9 KO mice, immunofluorescent stainings and investigated the expression of junctional proteins directly in intestinal epithelial cells of TNBS-inflamed mice by Western blot studies. The results demonstrated that sealing proteins like occludin were up regulated in the colon of inflamed IL-9 KO mice. In contrast, the tight junction protein Claudin1 showed lower expression levels when IL-9 is absent. Surprisingly, the pore-forming molecule Claudin2 revealed equal expression in TNBS-treated wild-type and IL-9-deficient animals. These results illustrate the pleiotropic functions of IL-9 in changing intestinal permeability in experimental colitis. Thus, modulation of IL-9 function emerges as a new approach for regulating barrier function in intestinal inflammation. PMID:25838986

  1. Bacillus subtilis Protects Porcine Intestinal Barrier from Deoxynivalenol via Improved Zonula Occludens-1 Expression

    PubMed Central

    Gu, Min Jeong; Song, Sun Kwang; Park, Sung Moo; Lee, In Kyu; Yun, Cheol-Heui

    2014-01-01

    Intestinal epithelial cells (IECs) forming the barrier for the first-line of protection are interconnected by tight junction (TJ) proteins. TJ alteration results in impaired barrier function, which causes potentially excessive inflammation leading to intestinal disorders. It has been suggested that toll-like receptor (TLR) 2 ligands and some bacteria enhance epithelial barrier function in humans and mice. However, no such study has yet to be claimed in swine. The aim of the present study was to examine whether Bacillus subtilis could improve barrier integrity and protection against deoxynivalenol (DON)-induced barrier disruption in porcine intestinal epithelial cell line (IPEC-J2). We found that B. subtilis decreased permeability of TJ and improved the expression of zonula occludens (ZO)-1 and occludin during the process of forming TJ. In addition, ZO-1 expression of IPEC-J2 cells treated with B. subtilis was up-regulated against DON-induced damage. In conclusion, B. subtilis may have potential to enhance epithelial barrier function and to prevent the cells from DON-induced barrier dysfunction. PMID:25049991

  2. Effects of acute intra-abdominal hypertension on multiple intestinal barrier functions in rats

    PubMed Central

    Leng, Yuxin; Yi, Min; Fan, Jie; Bai, Yu; Ge, Qinggang; Yao, Gaiqi

    2016-01-01

    Intra-abdominal hypertension (IAH) is a common and serious complication in critically ill patients for which there is no well-defined treatment strategy. Here, we explored the effect of IAH on multiple intestinal barriers and discussed whether the alteration in microflora provides clues to guide the rational therapeutic treatment of intestinal barriers during IAH. Using a rat model, we analysed the expression of tight junction proteins (TJs), mucins, chemotactic factors, and Toll-like receptor 4 (TLR4) by immunohistochemistry. We also analysed the microflora populations using 16S rRNA sequencing. We found that, in addition to enhanced permeability, acute IAH (20 mmHg for 90 min) resulted in significant disturbances to mucosal barriers. Dysbiosis of the intestinal microbiota was also induced, as represented by decreased Firmicutes (relative abundance), increased Proteobacteria and migration of Bacteroidetes from the colon to the jejunum. At the genus level, Lactobacillus species and Peptostreptococcaceae incertae sedis were decreased, whereas levels of lactococci remained unchanged. Our findings outline the characteristics of IAH-induced barrier changes, indicating that intestinal barriers might be treated to alleviate IAH, and the microflora may be an especially relevant target. PMID:26980423

  3. Death following traumatic brain injury in Drosophila is associated with intestinal barrier dysfunction

    PubMed Central

    Katzenberger, Rebeccah J; Chtarbanova, Stanislava; Rimkus, Stacey A; Fischer, Julie A; Kaur, Gulpreet; Seppala, Jocelyn M; Swanson, Laura C; Zajac, Jocelyn E; Ganetzky, Barry; Wassarman, David A

    2015-01-01

    Traumatic brain injury (TBI) is a major cause of death and disability worldwide. Unfavorable TBI outcomes result from primary mechanical injuries to the brain and ensuing secondary non-mechanical injuries that are not limited to the brain. Our genome-wide association study of Drosophila melanogaster revealed that the probability of death following TBI is associated with single nucleotide polymorphisms in genes involved in tissue barrier function and glucose homeostasis. We found that TBI causes intestinal and blood–brain barrier dysfunction and that intestinal barrier dysfunction is highly correlated with the probability of death. Furthermore, we found that ingestion of glucose after a primary injury increases the probability of death through a secondary injury mechanism that exacerbates intestinal barrier dysfunction. Our results indicate that natural variation in the probability of death following TBI is due in part to genetic differences that affect intestinal barrier dysfunction. DOI: http://dx.doi.org/10.7554/eLife.04790.001 PMID:25742603

  4. Numbers and distribution of immune cells in the tunica mucosa of the small and large intestine of full-thickness biopsies from healthy pet cats.

    PubMed

    Marsilio, S; Kleinschmidt, S; Harder, J; Nolte, I; Hewicker-Trautwein, M

    2011-02-01

    In this study, CD3(+) T lymphocytes and IgA(+) , IgG(+) and IgM(+) plasma cells were quantified in the tunica mucosa of the intestinal tract of 12 pet cats without gastrointestinal diseases. The study included full-thickness biopsies of the duodenum, jejunum, ileum and colon. The distribution and quantification of CD3(+) T cells, IgA(+) , IgG(+) and IgM(+) plasma cells within the intestinal tunica mucosa was performed by using immunohistochemical methods and computer-aided morphometry. CD3(+) T cells were significantly prominent in the villi and their numbers increased from duodenum to ileum but decreased towards the colon. The predominant type of plasma cells was IgA(+) cells, followed by IgM(+) cells. The number of IgG(+) cells was generally low compared to the other plasma cell types investigated. The results of the vertical distribution showed that IgA(+) and IgM(+) plasma cells were most numerous in the lower crypt areas, whilst IgG(+) plasma cells accumulated in the upper crypt region with a decline towards the villi and the lower crypt areas of control cats. All types of plasma cells showed a general decline from the duodenum towards the caudal sections of the intestinal tract regarding the horizontal distribution of plasma cells. This study provides a comprehensive overview on the vertical and horizontal distribution and the number of CD3(+) T cells and IgA(+) , IgG(+) and IgM(+) plasma cells in the intestinal tunica mucosa of pet cats.

  5. Xenobiotic Receptor-Mediated Regulation of Intestinal Barrier Function and Innate Immunity

    PubMed Central

    Ranhotra, Harmit S.; Flannigan, Kyle L.; Brave, Martina; Mukherjee, Subhajit; Lukin, Dana J.; Hirota, Simon A.; Mani, Sridhar

    2016-01-01

    The molecular basis for the regulation of the intestinal barrier is a very fertile research area. A growing body of knowledge supports the targeting of various components of intestinal barrier function as means to treat a variety of diseases, including the inflammatory bowel diseases. Herein, we will summarize the current state of knowledge of key xenobiotic receptor regulators of barrier function, highlighting recent advances, such that the field and its future are succinctly reviewed. We posit that these receptors confer an additional dimension of host-microbe interaction in the gut, by sensing and responding to metabolites released from the symbiotic microbiota, in innate immunity and also in host drug metabolism. The scientific evidence for involvement of the receptors and its molecular basis for the control of barrier function and innate immunity regulation would serve as a rationale towards development of non-toxic probes and ligands as drugs. PMID:27942535

  6. Nivalenol has a greater impact than deoxynivalenol on pig jejunum mucosa in vitro on explants and in vivo on intestinal loops.

    PubMed

    Cheat, Sophal; Gerez, Juliana R; Cognié, Juliette; Alassane-Kpembi, Imourana; Bracarense, Ana Paula F L; Raymond-Letron, Isabelle; Oswald, Isabelle P; Kolf-Clauw, Martine

    2015-05-29

    The mycotoxins deoxynivalenol (DON) and nivalenol (NIV), worldwide cereal contaminants, raise concerns for animal and human gut health, following contaminated food or feed ingestion. The impact of DON and NIV on intestinal mucosa was investigated after acute exposure, in vitro and in vivo. The histological changes induced by DON and NIV were analyzed after four-hour exposure on pig jejunum explants and loops, two alternative models. On explants, dose-dependent increases in the histological changes were induced by DON and NIV, with a two-fold increase in lesion severity at 10 µM NIV. On loops, NIV had a greater impact on the mucosa than DON. The overall proliferative cells showed 30% and 13% decrease after NIV and DON exposure, respectively, and NIV increased the proliferative index of crypt enterocytes. NIV also increased apoptosis at the top of villi and reduced by almost half the proliferative/apoptotic cell ratio. Lamina propria cells (mainly immune cells) were more sensitive than enterocytes (epithelial cells) to apoptosis induced by NIV. Our results demonstrate a greater impact of NIV than DON on the intestinal mucosa, both in vitro and in vivo, and highlight the need of a specific hazard characterization for NIV risk assessment.

  7. Nivalenol Has a Greater Impact than Deoxynivalenol on Pig Jejunum Mucosa in Vitro on Explants and in Vivo on Intestinal Loops

    PubMed Central

    Cheat, Sophal; Gerez, Juliana R.; Cognié, Juliette; Alassane-Kpembi, Imourana; Bracarense, Ana Paula F. L.; Raymond-Letron, Isabelle; Oswald, Isabelle P.; Kolf-Clauw, Martine

    2015-01-01

    The mycotoxins deoxynivalenol (DON) and nivalenol (NIV), worldwide cereal contaminants, raise concerns for animal and human gut health, following contaminated food or feed ingestion. The impact of DON and NIV on intestinal mucosa was investigated after acute exposure, in vitro and in vivo. The histological changes induced by DON and NIV were analyzed after four-hour exposure on pig jejunum explants and loops, two alternative models. On explants, dose-dependent increases in the histological changes were induced by DON and NIV, with a two-fold increase in lesion severity at 10 µM NIV. On loops, NIV had a greater impact on the mucosa than DON. The overall proliferative cells showed 30% and 13% decrease after NIV and DON exposure, respectively, and NIV increased the proliferative index of crypt enterocytes. NIV also increased apoptosis at the top of villi and reduced by almost half the proliferative/apoptotic cell ratio. Lamina propria cells (mainly immune cells) were more sensitive than enterocytes (epithelial cells) to apoptosis induced by NIV. Our results demonstrate a greater impact of NIV than DON on the intestinal mucosa, both in vitro and in vivo, and highlight the need of a specific hazard characterization for NIV risk assessment. PMID:26035490

  8. Effects of l-carnitine and/or maize distillers dried grains with solubles in diets of gestating and lactating sows on the intestinal barrier functions of their offspring.

    PubMed

    Wei, Bingdong; Nie, Shaoping; Meng, Qingwei; Qu, Zhe; Shan, Anshan; Chen, Zhihui

    2016-08-01

    The objective of this study was to investigate the effects of l-carnitine and/or maize distillers dried grains with solubles (DDGS) in diets of gestating and lactating sows on the intestinal barrier functions of their offspring. The experiment was designed as a 2×2 factorial with two dietary treatments (soyabean meal v. DDGS) and two l-carnitine levels (0 v. 100 mg/kg in gestating diets and 0 v. 200 mg/kg in lactating diets). Sows (Landrace×Large White) with an average parity of 4·2 with similar body weight were randomly assigned to four groups of thirty each. Dietary supplementation with l-carnitine increased the total superoxide dismutase activity but decreased the concentration of malondialdehyde of the jejunal mucosa in newborn piglets and weaning piglets on day 21. Dietary supplementation with l-carnitine decreased the concentrations of IL-1β, IL-12 and TNF-α in the jejunal mucosa of newborn piglets and decreased the concentrations of IL-6 and TNF-α in the jejunal mucosa of weaning piglets on day 21. There was an interaction between dietary treatment and l-carnitine on the bacterial numbers of total eubacteria in the digesta of caecum in weaning piglets on day 21. Bacterial numbers of total eubacteria in weaning piglets on day 21 were significantly increased by l-carnitine only in soyabean meal diet, but there was no significant effect of l-carnitine in DDGS-based diet. Dietary supplementation with l-carnitine increased the bacterial numbers of Lactobacillus spp. and bifidobacteria spp. in the digesta of caecum in weaning piglets on day 21. Dietary supplementation with l-carnitine in sows affected the expression of tight junction proteins (claudin 1, zonula occludens-1 (ZO-1) and occludin) in the jejunal mucosa of their offspring by increasing the expression of ZO-1 mRNA in the jejunal mucosa of newborn piglets, and by increasing the expression of ZO-1 and occludin mRNA in the jejunal mucosa of weaning piglets on day 21. In conclusion, dietary

  9. Glutamine supplementation improves intestinal barrier function in a weaned piglet model of Escherichia coli infection.

    PubMed

    Ewaschuk, Julia B; Murdoch, Gordon K; Johnson, Ian R; Madsen, Karen L; Field, Catherine J

    2011-09-01

    The weaning period is associated with an increased prevalence of gastrointestinal infection in many species. Glutamine (Gln) has been shown to improve intestinal barrier function and immune function in both in vivo and in vitro models. The objective of the present study was to determine the effect of dietary Gln supplementation on intestinal barrier function and intestinal cytokines in a model of Escherichia coli infection. We randomised 21-d-old piglets (n 20) to nutritionally complete isonitrogenous diets with or without Gln (4·4 %, w/w) for 2 weeks. Intestinal loops were isolated from anaesthetised pigs and inoculated with either saline or one of the two E. coli (K88AC or K88 wild-type)-containing solutions. Intestinal tissue was studied for permeability, cytokine expression, fluid secretion and tight-junction protein expression. Animals receiving Gln supplementation had decreased potential difference (PD) and short-circuit current (I(sc)) in E. coli-inoculated intestinal loops (PD 0·628 (SEM 0·151) mV; I(sc) 13·0 (SEM 3·07) μA/cm(2)) compared with control-fed animals (PD 1·36 (SEM 0·227) mV; I(sc) 22·4 (SEM 2·24) μA/cm(2)). Intestinal tissue from control, but not from Gln-supplemented, animals responded to E. coli with a significant increase in mucosal cytokine mRNA (IL-1β, IL-6, transforming growth factor-β and IL-10). Tight-junction protein expression (claudin-1 and occludin) was reduced with exposure to E. coli in control-fed animals and was not influenced in Gln-supplemented piglets. Gln supplementation may be useful in reducing the severity of weaning-related gastrointestinal infections, by reducing the mucosal cytokine response and altering intestinal barrier function.

  10. Effect of BML-111 on the intestinal mucosal barrier in sepsis and its mechanism of action.

    PubMed

    Liu, Huaizheng; Liu, Zuoliang; Zhao, Shangping; Sun, Chuanzheng; Yang, Mingshi

    2015-08-01

    5(S),6(R)-7-trihydroxymethyl heptanoate (BML-111) is an lipoxin A4 receptor agonist, which modulates the immune response and attenuates hemorrhagic shock-induced acute lung injury. However, the role of BML-111 in sepsis and in the intestinal mucosal barrier are not well understood. Therefore, the present study was designed to investigate the effect of BML-111 on the intestinal mucosal barrier in a rat model of sepsis. Furthermore, the molecular mechanism of action of BML-111 was evaluated. The cecal ligation and puncture-induced rat model of sepsis was constructed, and BML-111 was administered at three different doses. The results revealed that BML-111 suppressed the elevation of the pro-inflammatory cytokines tumor necrosis factor-α and interleukin-6, while enhancing the elevation of the anti-inflammatory cytokine transforming growth factor-β in the intestine. In addition, BML-111 significantly upregulated rat defensin-5 mRNA expression levels and downregulated the induction of cell apoptosis as well as caspase-3 activity in the intestine. All these results demonstrated that BML-111 exerted protective effects on the intestinal mucosal barrier in sepsis. Further, it was indicated that alterations in the expression of toll-like receptor (TLR)2 and TLR4 may be one of the molecular mechanisms underlying the protective effect of BML-111. The present study therefore suggested that BML-111 may be a novel therapeutic agent for sepsis.

  11. Probing the immune and healing response of murine intestinal mucosa by time-lapse 2-photon microscopy of laser-induced lesions with real-time dosimetry

    PubMed Central

    Orzekowsky-Schroeder, Regina; Klinger, Antje; Freidank, Sebastian; Linz, Norbert; Eckert, Sebastian; Hüttmann, Gereon; Gebert, Andreas; Vogel, Alfred

    2014-01-01

    Gut mucosa is an important interface between body and environment. Immune response and healing processes of murine small intestinal mucosa were investigated by intravital time-lapse two-photon excited autofluorescence microscopy of the response to localized laser-induced damage. Epithelial lesions were created by 355-nm, 500-ps pulses from a microchip laser that produced minute cavitation bubbles. Size and dynamics of these bubbles were monitored using a novel interferometric backscattering technique with 80 nm resolution. Small bubbles (< 2.5 µm maximum radius) merely resulted in autofluorescence loss of the target cell. Larger bubbles (7-25 µm) affected several cells and provoked immigration of immune cells (polymorphonuclear leucocytes). Damaged cells were expelled into the lumen, and the epithelium healed within 2 hours by stretching and migration of adjacent epithelial cells. PMID:25360369

  12. Zinc’s impact on intestinal barrier function and zinc trafficking during coccidial caccine challenge

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In order to evaluate the effects of Zn supplementation on intestinal barrier function and Zn trafficking, three dietary regimens were formulated: a basal corn/SBM diet formulated with a Zn-free vitamin/mineral premix (Basal), and two Zn regimens formulated to provide 90 mg/kg total dietary Zn from ...

  13. Heparan sulfate and syndecan-1 are essential in maintaining murine and human intestinal epithelial barrier function

    PubMed Central

    Bode, Lars; Salvestrini, Camilla; Park, Pyong Woo; Li, Jin-Ping; Esko, Jeffrey D.; Yamaguchi, Yu; Murch, Simon; Freeze, Hudson H.

    2007-01-01

    Patients with protein-losing enteropathy (PLE) fail to maintain intestinal epithelial barrier function and develop an excessive and potentially fatal efflux of plasma proteins. PLE occurs in ostensibly unrelated diseases, but emerging commonalities in clinical observations recently led us to identify key players in PLE pathogenesis. These include elevated IFN-γ, TNF-α, venous hypertension, and the specific loss of heparan sulfate proteoglycans from the basolateral surface of intestinal epithelial cells during PLE episodes. Here we show that heparan sulfate and syndecan-1, the predominant intestinal epithelial heparan sulfate proteoglycan, are essential in maintaining intestinal epithelial barrier function. Heparan sulfate– or syndecan-1–deficient mice and mice with intestinal-specific loss of heparan sulfate had increased basal protein leakage and were far more susceptible to protein loss induced by combinations of IFN-γ, TNF-α, and increased venous pressure. Similarly, knockdown of syndecan-1 in human epithelial cells resulted in increased basal and cytokine-induced protein leakage. Clinical application of heparin has been known to alleviate PLE in some patients but its unknown mechanism and severe side effects due to its anticoagulant activity limit its usefulness. We demonstrate here that non-anticoagulant 2,3-de-O-sulfated heparin could prevent intestinal protein leakage in syndecan-deficient mice, suggesting that this may be a safe and effective therapy for PLE patients. PMID:18064305

  14. Barrier function of the nasal mucosa in health and type-2 biased airway diseases.

    PubMed

    Zhang, N; Van Crombruggen, K; Gevaert, E; Bachert, C

    2016-03-01

    The mucosal lining of the upper airways represents the outer surface of the body to the ambient air and its contents and is prepared for it as the first line of defense. Apart from the well-described physical barrier and the mucociliary clearance, a variety of systems, including the airway microbiome, antimicrobial proteins, damage-associated molecular patterns, innate lymphoid cells, epithelial-derived cytokines and chemokines, and finally the adaptive immune system, as well as eosinophils as newly appreciated defense cells form different levels of protection against and response to any possible intruder. Of interest especially for allergic airway disease, mucosal germs might not just elicit a classical Th1/Th17-biased inflammatory response, but may directly induce a type-2 mucosal inflammation. Innovative therapeutic interventions may be possible at different levels also; however, whether modulations of the innate or adaptive immune responses will finally be more successful, and how the correction of the adaptive immune response might impact on the innate side, will be determined in the near future.

  15. Heat Stress Reduces Intestinal Barrier Integrity and Favors Intestinal Glucose Transport in Growing Pigs

    PubMed Central

    Pearce, Sarah C.; Mani, Venkatesh; Boddicker, Rebecca L.; Johnson, Jay S.; Weber, Thomas E.; Ross, Jason W.; Rhoads, Robert P.; Baumgard, Lance H.; Gabler, Nicholas K.

    2013-01-01

    Excessive heat exposure reduces intestinal integrity and post-absorptive energetics that can inhibit wellbeing and be fatal. Therefore, our objectives were to examine how acute heat stress (HS) alters intestinal integrity and metabolism in growing pigs. Animals were exposed to either thermal neutral (TN, 21°C; 35–50% humidity; n = 8) or HS conditions (35°C; 24–43% humidity; n = 8) for 24 h. Compared to TN, rectal temperatures in HS pigs increased by 1.6°C and respiration rates by 2-fold (P<0.05). As expected, HS decreased feed intake by 53% (P<0.05) and body weight (P<0.05) compared to TN pigs. Ileum heat shock protein 70 expression increased (P<0.05), while intestinal integrity was compromised in the HS pigs (ileum and colon TER decreased; P<0.05). Furthermore, HS increased serum endotoxin concentrations (P = 0.05). Intestinal permeability was accompanied by an increase in protein expression of myosin light chain kinase (P<0.05) and casein kinase II-α (P = 0.06). Protein expression of tight junction (TJ) proteins in the ileum revealed claudin 3 and occludin expression to be increased overall due to HS (P<0.05), while there were no differences in claudin 1 expression. Intestinal glucose transport and blood glucose were elevated due to HS (P<0.05). This was supported by increased ileum Na+/K+ ATPase activity in HS pigs. SGLT-1 protein expression was unaltered; however, HS increased ileal GLUT-2 protein expression (P = 0.06). Altogether, these data indicate that HS reduce intestinal integrity and increase intestinal stress and glucose transport. PMID:23936392

  16. High-throughput sequencing reveals differing immune responses in the intestinal mucosa of two inbred lines afflicted with necrotic enteritis.

    PubMed

    Truong, Anh Duc; Hong, Yeong Ho; Lillehoj, Hyun S

    2015-08-15

    We investigated the necrotic enteritis (NE)-induced transcripts of immune-related genes in the intestinal mucosa of two highly inbred White Leghorn chicken lines, line 6.3 and line 7.2, which share the same MHC haplotype and show different levels of NE susceptibility using high-throughput RNA sequencing (RNA-Seq) technology. NE was induced by the previously described co-infection model using Eimeria maxima and Clostridium perfringens. The RNA-Seq generated over 38 million sequence reads for Marek's disease (MD)-resistant line 6.3 and over 40 million reads for the MD-susceptible line 7.2. Alignment of these sequences with the Gallus gallus genome database revealed the expression of over 29,900 gene transcripts induced by NE in these two lines, among which 7,841 genes were significantly upregulated and 2,919 genes were downregulated in line 6.3 chickens and 6,043 genes were significantly upregulated and 2,764 genes were downregulated in NE-induced line 7.2 compared with their uninfected controls. Analysis of 560 differentially expressed genes (DEGs) using the gene ontology database revealed annotations for 246 biological processes, 215 molecular functions, and 81 cellular components. Among the 53 cytokines and 96 cytokine receptors, 15 cytokines and 29 cytokine receptors were highly expressed in line 6.3, whereas the expression of 15 cytokines and 15 cytokine receptors was higher in line 7.2 than in line 6.3 (fold change ≥ 2, p<0.01). In a hierarchical cluster analysis of novel mRNAs, the novel mRNA transcriptome showed higher expression in line 6.3 than in line 7.2, which is consistent with the expression profile of immune-related target genes. In qRT-PCR and RNA-Seq analysis, all the genes examined showed similar responses to NE (correlation coefficient R=0.85-0.89, p<0.01) in both lines 6.3 and 7.2. This study is the first report describing NE-induced DEGs and novel transcriptomes using RNA-seq data from two inbred chicken lines showing different levels of NE

  17. Human small intestinal mucosa harbours a small population of cytolytically active CD8+ αβ T lymphocytes

    PubMed Central

    Melgar, Silvia; Bas, Anna; Hammarström, Sten; Hammarström, Marie-Louise

    2002-01-01

    Intraepithelial lymphocytes (IEL) in normal human small intestine exhibit cytotoxicity. This study was undertaken to characterize the effector cells and their mode of action. Freshly isolated jejunal IEL and lamina propria lymphocytes (LPL), as well as IEL and LPL depleted of CD4+, CD8+ and T-cell receptor (TCR)-γδ+ cells were used as effector cells in anti-CD3-mediated redirected cytotoxicity against a murine FcγR-expressing cell line. Effector cell frequencies were estimated by effector to target cell titration and limiting dilution. The capacity of IEL and LPL to kill a Fas-expressing human T-cell line was also analysed. T-cell subsets were analysed for perforin, granzyme B, Fas-ligand (FasL), tumour necrosis factor-α (TNF-α) and TNF-related apoptosis inducing ligand (TRAIL) mRNA expression by reverse transcription–polymerase chain reaction (RT-PCR). Frequencies of IEL expressing the perforin and FasL proteins were determined by immunomorphometry. Both IEL and LPL exhibited significant Ca2+-dependent, anti-CD3-mediated cytotoxicity, ≈ 30% specific lysis at the effector to target cell ratio 100. The cytotoxic cells constituted, however, only a small fraction of IEL and LPL (≈ 0·01%). CD8+ TCR-αβ+ cells accounted for virtually all the cytotoxicity and expressed mRNA for all five cytotoxic proteins. The frequency of granzyme B-expressing samples was higher in CD8+ cells than in CD4+ cells (P<0·05 and <0·01 for IEL and LPL, respectively). In addition, both IEL and LPL exhibited significant spontaneous anti-CD3-independent cytotoxicity against Fas-expressing human T cells. This killing was mediated by Fas–FasL interaction. On average, 2–3% of the IEL expressed perforin and FasL. We speculate that CD8+ memory cells accumulate in the jejunal mucosa and that the CD8+ TCR-αβ+ lymphocytes executing TCR/CD3-mediated, Ca2+-dependent cytotoxicity are classical cytotoxic T lymphocytes ‘caught in the act’ of eliminating infected epithelial cells

  18. Claudin-2 as a mediator of leaky gut barrier during intestinal inflammation.

    PubMed

    Luettig, J; Rosenthal, R; Barmeyer, C; Schulzke, J D

    2015-01-01

    The epithelial tight junction determines the paracellular water and ion movement in the intestine and also prevents uptake of larger molecules, including antigens, in an uncontrolled manner. Claudin-2, one of the 27 mammalian claudins regulating that barrier function, forms a paracellular channel for small cations and water. It is typically expressed in leaky epithelia like proximal nephron and small intestine and provides a major pathway for the paracellular transport of sodium, potassium, and fluid. In intestinal inflammation (Crohn's disease, ulcerative colitis), immune-mediated diseases (celiac disease), and infections (HIV enteropathy), claudin-2 is upregulated in small and large intestine and contributes to diarrhea via a leak flux mechanism. In parallel to that upregulation, other epithelial and tight junctional features are altered and the luminal uptake of antigenic macromolecules is enhanced, for which claudin-2 may be partially responsible through induction of tight junction strand discontinuities.

  19. Prevention of Barrier Disruption by Heme Oxygenase-1 in Intestinal Bleeding Model.

    PubMed

    Akagi, Reiko; Akagi, Masaaki; Hatori, Yuta; Inouye, Sachiye

    2016-01-01

    In this study we investigated the effect of free heme, the local level of which was increased by bleeding, on the intestinal barrier function, using human epithelial colorectal adenocarcinoma cells (Caco-2). Our results show that the addition of hemin to the culture medium markedly disrupted the barrier function, which was significantly improved by glutamine supplementation. Although hemin treatment caused the increased expression of heme oxygenase (HO)-1, the inhibition of HO activity resulted in the aggravation of hemin-induced barrier dysfunction. Up-regulation of HO-1 by pretreatment with a low concentration of hemin almost completely prevented hemin-induced barrier dysfunction. Taken together, these observations indicate that an abnormally high level of intracellular free heme causes barrier dysfunction, probably through the modulation of proteins forming tight junctions.

  20. Oral Administration of Probiotics Inhibits Absorption of the Heavy Metal Cadmium by Protecting the Intestinal Barrier

    PubMed Central

    Zhai, Qixiao; Tian, Fengwei; Zhao, Jianxin; Zhang, Hao; Narbad, Arjan

    2016-01-01

    ABSTRACT The heavy metal cadmium (Cd) is an environmental pollutant that causes adverse health effects in humans and animals. Our previous work demonstrated that oral administration of probiotics can significantly inhibit Cd absorption in the intestines of mice, but further evidence is needed to gain insights into the related protection mode. The goal of this study was to evaluate whether probiotics can inhibit Cd absorption through routes other than the Cd binding, with a focus on gut barrier protection. In the in vitro assay, both the intervention and therapy treatments of Lactobacillus plantarum CCFM8610 alleviated Cd-induced cytotoxicity in the human intestinal cell line HT-29 and protected the disruption of tight junctions in the cell monolayers. In a mouse model, probiotics with either good Cd-binding or antioxidative ability increased fecal Cd levels and decreased Cd accumulation in the tissue of Cd-exposed mice. Compared with the Cd-only group, cotreatment with probiotics also reversed the disruption of tight junctions, alleviated inflammation, and decreased the intestinal permeability of mice. L. plantarum CCFM8610, a strain with both good Cd binding and antioxidative abilities, exhibited significantly better protection than the other two strains. These results suggest that along with initial intestinal Cd sequestration, probiotics can inhibit Cd absorption by protecting the intestinal barrier, and the protection is related to the alleviation of Cd-induced oxidative stress. A probiotic with both good Cd-binding and antioxidative capacities can be used as a daily supplement for the prevention of oral Cd exposure. IMPORTANCE The heavy metal cadmium (Cd) is an environmental pollutant that causes adverse health effects in humans and animals. For the general population, food and drinking water are the main sources of Cd exposure due to the biomagnification of Cd within the food chain; therefore, the intestinal tract is the first organ that is susceptible to Cd

  1. Cytotoxic Th1 and Th17 cells infiltrate the intestinal mucosa of Behcet patients and exhibit high levels of TNF-α in early phases of the disease

    PubMed Central

    Emmi, Giacomo; Silvestri, Elena; Bella, Chiara Della; Grassi, Alessia; Benagiano, Marisa; Cianchi, Fabio; Squatrito, Danilo; Cantarini, Luca; Emmi, Lorenzo; Selmi, Carlo; Prisco, Domenico; D’Elios, Mario Milco

    2016-01-01

    Abstract Background: Gastrointestinal involvement is one of the most serious in Behçet disease, potentially leading to severe complications. Aim of this study was to investigate at mucosal level the T-cell responses in Behçet patients with early intestinal involvement. Methods: We isolated T cells from intestinal mucosa of 8 patients with intestinal symptoms started within 6 months. T lymphocytes were cloned and analyzed for surface phenotype and cytokines production. Results: We obtained 382 T-cell clones: 324 were CD4+ and 58 were CD8+. Within the 324 CD4+ clones, 195 were able to secrete IFN-γ and TNF-α, but not IL-4, nor IL-17 thus showing a polarized Th1 profile, whereas CD4 clones producing both IFN-γ and IL-17 (Th1/Th17 profile) were 79. Likewise, the number of CD8 clones producing type 1 cytokines was higher than those of CD8 clones producing both type 1 and 2 cytokines. Almost all intestinal-derived T-cell clones expressed perforin-mediated cytotoxicity and Fas–Fas Ligand-mediated pro-apoptotic activity. Conclusions: Our results indicate that in the early stages of the disease, both Th1 and Th17 cells drive inflammation leading to mucosal damage via abnormal and long-lasting cytokines production as well as via both perforin- and Fas–Fas ligand-mediated cytotoxicity. Finally, all the T cells at mucosal level were able to produce large amount of TNF-α, suggesting that its production is a property of intestinal T cells of patients with early active intestinal disease. These results support the therapy with anti-TNF-α agents and suggest the use of anti-IL-17 monoclonal antibodies in Behçet patients with early intestinal involvement. PMID:27930541

  2. Breaking down the barriers: the gut microbiome, intestinal permeability and stress-related psychiatric disorders.

    PubMed

    Kelly, John R; Kennedy, Paul J; Cryan, John F; Dinan, Timothy G; Clarke, Gerard; Hyland, Niall P

    2015-01-01

    The emerging links between our gut microbiome and the central nervous system (CNS) are regarded as a paradigm shift in neuroscience with possible implications for not only understanding the pathophysiology of stress-related psychiatric disorders, but also their treatment. Thus the gut microbiome and its influence on host barrier function is positioned to be a critical node within the brain-gut axis. Mounting preclinical evidence broadly suggests that the gut microbiota can modulate brain development, function and behavior by immune, endocrine and neural pathways of the brain-gut-microbiota axis. Detailed mechanistic insights explaining these specific interactions are currently underdeveloped. However, the concept that a "leaky gut" may facilitate communication between the microbiota and these key signaling pathways has gained traction. Deficits in intestinal permeability may underpin the chronic low-grade inflammation observed in disorders such as depression and the gut microbiome plays a critical role in regulating intestinal permeability. In this review we will discuss the possible role played by the gut microbiota in maintaining intestinal barrier function and the CNS consequences when it becomes disrupted. We will draw on both clinical and preclinical evidence to support this concept as well as the key features of the gut microbiota which are necessary for normal intestinal barrier function.

  3. Subacute stress and chronic stress interact to decrease intestinal barrier function in rats.

    PubMed

    Lauffer, Adriana; Vanuytsel, Tim; Vanormelingen, Christophe; Vanheel, Hanne; Salim Rasoel, Shadea; Tóth, Joran; Tack, Jan; Fornari, Fernando; Farré, Ricard

    2016-01-01

    Psychological stress increases intestinal permeability, potentially leading to low-grade inflammation and symptoms in functional gastrointestinal disorders. We assessed the effect of subacute, chronic and combined stress on intestinal barrier function and mast cell density. Male Wistar rats were allocated to four experimental groups (n = 8/group): 1/sham; 2/subacute stress (isolation and limited movement for 24 h); 3/chronic crowding stress for 14 days and 4/combined subacute and chronic stress. Jejunum and colon were collected to measure: transepithelial electrical resistance (TEER; a measure of epithelial barrier function); gene expression of tight junction molecules; mast cell density. Plasma corticosterone concentration was increased in all three stress conditions versus sham, with highest concentrations in the combined stress condition. TEER in the jejunum was decreased in all stress conditions, but was significantly lower in the combined stress condition than in the other groups. TEER in the jejunum correlated negatively with corticosterone concentration. Increased expression of claudin 1, 5 and 8, occludin and zonula occludens 1 mRNAs was detected after subacute stress in the jejunum. In contrast, colonic TEER was decreased only after combined stress, and the expression of tight junction molecules was unaltered. Increased mast cell density was observed in the chronic and combined stress condition in the colon only. In conclusion, our data show that chronic stress sensitizes the gastrointestinal tract to the effects of subacute stress on intestinal barrier function; different underlying cellular and molecular alterations are indicated in the small intestine versus the colon.

  4. Breaking down the barriers: the gut microbiome, intestinal permeability and stress-related psychiatric disorders

    PubMed Central

    Kelly, John R.; Kennedy, Paul J.; Cryan, John F.; Dinan, Timothy G.; Clarke, Gerard; Hyland, Niall P.

    2015-01-01

    The emerging links between our gut microbiome and the central nervous system (CNS) are regarded as a paradigm shift in neuroscience with possible implications for not only understanding the pathophysiology of stress-related psychiatric disorders, but also their treatment. Thus the gut microbiome and its influence on host barrier function is positioned to be a critical node within the brain-gut axis. Mounting preclinical evidence broadly suggests that the gut microbiota can modulate brain development, function and behavior by immune, endocrine and neural pathways of the brain-gut-microbiota axis. Detailed mechanistic insights explaining these specific interactions are currently underdeveloped. However, the concept that a “leaky gut” may facilitate communication between the microbiota and these key signaling pathways has gained traction. Deficits in intestinal permeability may underpin the chronic low-grade inflammation observed in disorders such as depression and the gut microbiome plays a critical role in regulating intestinal permeability. In this review we will discuss the possible role played by the gut microbiota in maintaining intestinal barrier function and the CNS consequences when it becomes disrupted. We will draw on both clinical and preclinical evidence to support this concept as well as the key features of the gut microbiota which are necessary for normal intestinal barrier function. PMID:26528128

  5. PHD3 Stabilizes the Tight Junction Protein Occludin and Protects Intestinal Epithelial Barrier Function*

    PubMed Central

    Chen, Ying; Zhang, Hai-Sheng; Fong, Guo-Hua; Xi, Qiu-Lei; Wu, Guo-Hao; Bai, Chen-Guang; Ling, Zhi-Qiang; Fan, Li; Xu, Yi-Ming; Qin, Yan-Qing; Yuan, Tang-Long; Sun, Heng; Fang, Jing

    2015-01-01

    Prolyl hydroxylase domain proteins (PHDs) control cellular adaptation to hypoxia. PHDs are found involved in inflammatory bowel disease (IBD); however, the exact role of PHD3, a member of the PHD family, in IBD remains unknown. We show here that PHD3 plays a critical role in maintaining intestinal epithelial barrier function. We found that genetic ablation of Phd3 in intestinal epithelial cells led to spontaneous colitis in mice. Deletion of PHD3 decreases the level of tight junction protein occludin, leading to a failure of intestinal epithelial barrier function. Further studies indicate that PHD3 stabilizes occludin by preventing the interaction between the E3 ligase Itch and occludin, in a hydroxylase-independent manner. Examination of biopsy of human ulcerative colitis patients indicates that PHD3 is decreased with disease severity, indicating that PHD3 down-regulation is associated with progression of this disease. We show that PHD3 protects intestinal epithelial barrier function and reveal a hydroxylase-independent function of PHD3 in stabilizing occludin. These findings may help open avenues for developing a therapeutic strategy for IBD. PMID:26124271

  6. High therapeutic efficacy of Cathelicidin-WA against postweaning diarrhea via inhibiting inflammation and enhancing epithelial barrier in the intestine

    PubMed Central

    Yi, Hongbo; Zhang, Lin; Gan, Zhenshun; Xiong, Haitao; Yu, Caihua; Du, Huahua; Wang, Yizhen

    2016-01-01

    Diarrhea is a leading cause of death among young mammals, especially during weaning. Here, we investigated the effects of Cathelicidin-WA (CWA) on diarrhea, intestinal morphology, inflammatory responses, epithelial barrier and microbiota in the intestine of young mammals during weaning. Piglets with clinical diarrhea were selected and treated with saline (control), CWA or enrofloxacin (Enro) for 4 days. Both CWA and Enro effectively attenuated diarrhea. Compared with the control, CWA decreased IL-6, IL-8 and IL-22 levels and reduced neutrophil infiltration into the jejunum. CWA inhibited inflammation by down-regulating the TLR4-, MyD88- and NF-κB-dependent pathways. Additionally, CWA improved intestinal morphology by increasing villus and microvillus heights and enhancing intestinal barrier function by increasing tight junction (TJ) protein expression and augmenting wound-healing ability in intestinal epithelial cells. CWA also improved microbiota composition and increased short-chain fatty acid (SCFA) levels in feces. By contrast, Enro not only disrupted the intestinal barrier but also negatively affected microbiota composition and SCFA levels in the intestine. In conclusion, CWA effectively attenuated inflammation, enhanced intestinal barrier function, and improved microbiota composition in the intestines of weaned piglets. These results suggest that CWA could be an effective and safe therapy for diarrhea or other intestinal diseases in young mammals. PMID:27181680

  7. Escherichia coli challenge and one type of smectite alter intestinal barrier of pigs

    PubMed Central

    2013-01-01

    An experiment was conducted to determine how an E. coli challenge and dietary clays affect the intestinal barrier of pigs. Two groups of 32 pigs (initial BW: 6.9 ± 1.0 kg) were distributed in a 2 × 4 factorial arrangement of a randomized complete block design (2 challenge treatments: sham or E. coli, and 4 dietary treatments: control, 0.3% smectite A, 0.3% smectite B and 0.3% zeolite), with 8 replicates total. Diarrhea score, growth performance, goblet cell size and number, bacterial translocation from intestinal lumen to lymph nodes, intestinal morphology, and relative amounts of sulfo and sialo mucins were measured. The E. coli challenge reduced performance, increased goblet cell size and number in the ileum, increased bacterial translocation from the intestinal lumen to the lymph nodes, and increased ileal crypt depth. One of the clays (smectite A) tended to increase goblet cell size in ileum, which may indicate enhanced protection. In conclusion, E. coli infection degrades intestinal barrier integrity but smectite A may enhance it. PMID:24359581

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

    SciTech Connect

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

    2010-06-15

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

  9. Impaired function of the intestinal barrier in a novel sub-health rat model

    PubMed Central

    FENG, SISI; LIU, WEIDONG; ZUO, SHENGNAN; XIE, TINGYAN; DENG, HUI; ZHANG, QIUHUAN; ZHONG, BAIYUN

    2016-01-01

    Sub-health is a state featuring a deterioration in physiological function between health and illness, and the sub-health condition has surfaced as life-threatening in humans. The aim of the present study was to establish a sub-health model in rats, and investigate the function of the intestinal barrier in the sub-health rats and rats following intervention. To establish a sub-health model, the rats were subjected to a high-fat and sugar diet, motion restriction and chronic stress. Their serum glucose and triglyceride levels, immune function and adaptability were then measured. The levels of diamine oxidase and D-lactic acid in the plasma were analyzed as markers of the intestinal permeability. The protein and mRNA expression levels of anti-apoptotic YWHAZ in the colonic tissue was detected using immunohistochemical and reverse transcription-quantitative polymerase chain reaction analyses In the present study, the sub-health rat model was successfully established, and sub-health factors increased the intestinal permeability and reduced the expression of YWHAZ. Providing sub-health rats with normal living conditions did not improve the function of the intestinal barrier. In conclusion, the results of the present study demonstrated that intestinal disorders in the sub-health rat model may result from the damage caused by reduce intestinal barrier function as well as the decreased expression levels of YWHAZ. Additionally, rats in the sub-health condition did not recover following subsequent exposure to normal living conditions, suggesting that certain exercises or medical intervention may be necessary to improve sub-health symptoms. PMID:26957295

  10. Partial Enteral Nutrition Mitigated Ischemia/Reperfusion-Induced Damage of Rat Small Intestinal Barrier

    PubMed Central

    Wu, Chao; Wang, Xinying; Jiang, Tingting; Li, Chaojun; Zhang, Li; Gao, Xuejin; Tian, Feng; Li, Ning; Li, Jieshou

    2016-01-01

    Background and Aims: This study was designed to investigate a relatively optimum dose of partial enteral nutrition (PEN) which effectively attenuates intestinal barrier dysfunction initiated by ischemia/reperfusion injury (IRI). Methods: In experiment 1, 60 male Sprague-Dawley (SD) rats were subjected to intestinal IRI and assigned to six groups according to the different proportion of EN administrations: namely total parenteral nutrition (TPN or 0%EN), 10%EN, 20%EN, 40%EN, 60%EN, and total enteral nutrition (TEN or 100%) groups, the deficits of intraluminal calorie were supplemented by PN. In experiment 2, 50 male SD rats were subjected to intestinal IRI and divided into five groups based on the results of experiment 1: TPN, TEN, 20%EN, TPN plus pretreatment with NF-κB antagonist 30 min before IRI (TPN+PDTC), and TPN plus pretreatment with HIF-1α antagonist 30 min before IRI (TPN+YC-1) groups. Results: In experiment 1, previous IRI combined with subsequent EN shortage disrupted the structure of intestinal epithelial cell and tight junctions (TJs). While 20% dose of EN had an obviously protective effect on these detrimental consequences. In experiment 2, compared with TPN only, 20%EN exerted a significant protection of barrier function of intestinal epithelium. Analogous results were observed when TPN combined with specific NF-κB/HIF-1α inhibitors (PDTC and YC-1). Meanwhile, the expression of NF-κB/HIF-1α had a similar trend among the groups. Conclusions: Our findings indicate that 20%EN is the minimally effective dosage of EN which promotes the recovery of intestinal barrier function after IRI in a rat model. Furthermore, we discreetly speculate that this benefit is, at least partly, related to NF-κB/HIF-1α pathway expression. PMID:27548209

  11. Curcumin improves intestinal barrier function: modulation of intracellular signaling, and organization of tight junctions.

    PubMed

    Wang, Jing; Ghosh, Siddhartha S; Ghosh, Shobha

    2017-04-01

    Association between circulating lipopolysaccharide (LPS) and metabolic diseases (such as type 2 diabetes and atherosclerosis) has shifted the focus from high-fat high-cholesterol containing Western-type diet (WD)-induced changes in gut microbiota per se to release of gut bacteria-derived products (e.g., LPS) into circulation due to intestinal barrier dysfunction as the possible mechanism for the chronic inflammatory state underlying the development of these diseases. We demonstrated earlier that oral supplementation with curcumin attenuates WD-induced development of type 2 diabetes and atherosclerosis. Poor bioavailability of curcumin has precluded the establishment of a causal relationship between oral supplementation and it is in vivo effects. We hypothesized that curcumin attenuates WD-induced chronic inflammation and associated metabolic diseases by modulating the function of intestinal epithelial cells (IECs) and the intestinal barrier function. The objective of the present study was to delineate the underlying mechanisms. The human IEC lines Caco-2 and HT-29 were used for these studies and modulation of direct as well as indirect effects of LPS on intracellular signaling as well as tight junctions were examined. Pretreatment with curcumin significantly attenuated LPS-induced secretion of master cytokine IL-1β from IECs and macrophages. Furthermore, curcumin also reduced IL-1β-induced activation of p38 MAPK in IECs and subsequent increase in expression of myosin light chain kinase involved in the phosphorylation of tight junction proteins and ensuing disruption of their normal arrangement. The major site of action of curcumin is, therefore, likely the IECs and the intestinal barrier, and by reducing intestinal barrier dysfunction, curcumin modulates chronic inflammatory diseases despite poor bioavailability.

  12. Administration of different Lactobacillus strains in fermented oatmeal soup: in vivo colonization of human intestinal mucosa and effect on the indigenous flora.

    PubMed Central

    Johansson, M L; Molin, G; Jeppsson, B; Nobaek, S; Ahrné, S; Bengmark, S

    1993-01-01

    In vivo colonization by different Lactobacillus strains on human intestinal mucosa of healthy volunteers was studied together with the effect of Lactobacillus administration on different groups of indigenous bacteria. A total of 19 test strains were administered in fermented oatmeal soup containing 5 x 10(6) CFU of each strain per ml by using a dose of 100 ml of soup per day for 10 days. Biopsies were taken from both the upper jejunum and the rectum 1 day before administration was started and 1 and 11 days after administration was terminated. The administration significantly increased the Lactobacillus counts on the jejunum mucosa, and high levels remained 11 days after administration was terminated. The levels of streptococci increased by 10- to 100-fold in two persons, and the levels of sulfite-reducing clostridia in the jejunum decreased by 10- to 100-fold in three of the volunteers 1 day after administration was terminated. In recta, the anaerobic bacterium counts and the gram-negative anaerobic bacterium counts decreased significantly by the end of administration. Furthermore, a decrease in the number of members of the Enterobacteriaceae by 1,000-fold was observed on the rectal mucosa of two persons. Randomly picked Lactobacillus isolates were identified phenotypically by API 50CH tests and genotypically by the plasmid profiles of strains and by restriction endonuclease analysis of chromosomal DNAs.(ABSTRACT TRUNCATED AT 250 WORDS) Images PMID:8439146

  13. Intestinal permeability, leaky gut, and intestinal disorders.

    PubMed

    Hollander, D

    1999-10-01

    A major task of the intestine is to form a defensive barrier to prevent absorption of damaging substances from the external environment. This protective function of the intestinal mucosa is called permeability. Clinicians can use inert, nonmetabolized sugars such as mannitol, rhamnose, or lactulose to measure the permeability barrier or the degree of leakiness of the intestinal mucosa. Ample evidence indicates that permeability is increased in most patients with Crohn's disease and in 10% to 20% of their clinically healthy relatives. The abnormal leakiness of the mucosa in Crohn's patients and their relatives can be greatly amplified by aspirin preadministration. Permeability measurements in Crohn's patients reflect the activity, extent, and distribution of the disease and may allow us to predict the likelihood of recurrence after surgery or medically induced remission. Permeability is also increased in celiac disease and by trauma, burns, and nonsteroidal anti-inflammatory drugs. The major determinant of the rate of intestinal permeability is the opening or closure of the tight junctions between enterocytes in the paracellular space. As we broaden our understanding of the mechanisms and agents that control the degree of leakiness of the tight junctions, we will be increasingly able to use permeability measurements to study the etiology and pathogenesis of various disorders and to design or monitor therapies for their management.

  14. Glucagon-like peptide-2 protects impaired intestinal mucosal barriers in obstructive jaundice rats

    PubMed Central

    Chen, Jun; Dong, Jia-Tian; Li, Xiao-Jing; Gu, Ye; Cheng, Zhi-Jian; Cai, Yuan-Kun

    2015-01-01

    AIM: To observe the protective effect of glucagon-like peptide-2 (GLP-2) on the intestinal barrier of rats with obstructive jaundice and determine the possible mechanisms of action involved in the protective effect. METHODS: Thirty-six Sprague-Dawley rats were randomly divided into a sham operation group, an obstructive jaundice group, and a GLP-2 group; each group consisted of 12 rats. The GLP-2 group was treated with GLP-2 after the day of surgery, whereas the other two groups were treated with the same concentration of normal saline. Alanine aminotransferase (ALT), total bilirubin, and endotoxin levels were recorded at 1, 3, 7, 10 and 14 d. Furthermore, on the 14th day, body weight, the wet weight of the small intestine, pathological changes of the small intestine and the immunoglobulin A (IgA) expressed by plasma cells located in the small intestinal lamina propria were recorded for each group. RESULTS: In the rat model, jaundice was obvious, and the rats’ activity decreased 4-6 d post bile duct ligation. Compared with the sham operation group, the obstructive jaundice group displayed increased yellow staining of abdominal visceral serosa, decreased small intestine wet weight, thinning of the intestinal muscle layer and villi, villous atrophy, uneven height, fusion, partial villous epithelial cell shedding, substantial inflammatory cell infiltration and significantly reduced IgA expression. However, no significant gross changes were noted between the GLP-2 and sham groups. With time, the levels of ALT, endotoxin and bilirubin in the GLP-2 group were significantly increased compared with the sham group (P < 0.01). The increasing levels of the aforementioned markers were more significant in the obstructive jaundice group than in the GLP-2 group (P < 0.01). CONCLUSION: GLP-2 reduces intestinal mucosal injuries in obstructive jaundice rats, which might be attributed to increased intestinal IgA and reduced bilirubin and endotoxin. PMID:25593463

  15. Carotenoids, Retinol, and Intestinal Barrier Function in Children From Northeastern Brazil

    PubMed Central

    Vieira, Milena M.; Paik, Jisun; Blaner, William S.; Soares, Alberto M.; Mota, Rosa M.S.; Guerrant, Richard L.; Lima, Aldo A.M.

    2009-01-01

    Objectives To investigate the association of carotenoids and retinol (vitamin A) with intestinal barrier function in children in an urban community in Fortaleza, northeastern Brazil. Methods Descriptive analysis of serum carotenoids and retinol concentrations with intestinal barrier function in 102 children from an urban community, July 2000 to August 2001. Results The weight for height z score (wasting) showed that 19.6% (20/102) had mild malnutrition (–1 to –2 z score). All of the children's serum retinol concentrations were determined and none were severely deficient (≤0.35 μmol/L), 2.9% (3/102) were moderately (0.36–0.70 μmol/L) deficient, 20.6% (21/102) were mildly (0.71–1.05 μmol/L) deficient; 76.5% (78/102) were vitamin A sufficient (>1.05 μmol/L). The lactulose:mannitol (L/M) ratio was elevated (≥0.0864) in 49% (47/97) of children when compared with healthy children with normal L/M ratio (<0.0864) in the same geographic area. Serum carotenoids, lutein, β-cryptoxanthin and β-carotene showed significant inverse correlations with the L/M ratio, but not lutein after adjusting for age. Acute phase proteins (C-reactive protein and β-acid glycoprotein) were significantly inversely correlated with retinol but not with carotenoids. Retinol and retinol-binding protein were not significantly associated with L/M ratio. Conclusions These data suggest a disruption of intestinal barrier function in the paracellular pathway with low serum concentrations of carotenoids. Carotenoids may provide a better marker for disrupted intestinal barrier function than retinol-binding protein or retinol. PMID:18955868

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

    PubMed

    Wang, Kai; Jin, Xiaolu; Chen, Yifan; Song, Zehe; Jiang, Xiasen; Hu, Fuliang; Conlon, Michael A; Topping, David L

    2016-05-07

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

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

    PubMed Central

    Wang, Kai; Jin, Xiaolu; Chen, Yifan; Song, Zehe; Jiang, Xiasen; Hu, Fuliang; Conlon, Michael A.; Topping, David L.

    2016-01-01

    Propolis has abundant polyphenolic constituents and is used widely as a health/functional food. Here, we investigated the effects of polyphenol-rich propolis extracts (PPE) on intestinal barrier function in human intestinal epithelial Caco-2 cells, as well as in rats. In Caco-2 cells, PPE increased transepithelial electrical resistance and decreased lucifer yellow flux. PPE-treated cells showed increased expression of the tight junction (TJ) loci occludin and zona occludens (ZO)-1. Confocal microscopy showed organized expressions in proteins related to TJ assembly, i.e., occludin and ZO-1, in response to PPE. Furthermore, PPE led to the activation of AMPK, ERK1/2, p38, and Akt. Using selective inhibitors, we found that the positive effects of PPE on barrier function were abolished in cells in which AMPK and ERK1/2 signaling were inhibited. Moreover, rats fed a diet supplemented with PPE (0.3% in the diet) exhibited increased colonic epithelium ZO-1 expression. Overall, these data suggest that PPE strengthens intestinal barrier function by activating AMPK and ERK signaling and provide novel insights into the potential application of propolis for human gut health. PMID:27164138

  18. Binding Studies on Isolated Porcine Small Intestinal Mucosa and in vitro Toxicity Studies Reveal Lack of Effect of C. perfringens Beta-Toxin on the Porcine Intestinal Epithelium

    PubMed Central

    Roos, Simone; Wyder, Marianne; Candi, Ahmet; Regenscheit, Nadine; Nathues, Christina; van Immerseel, Filip; Posthaus, Horst

    2015-01-01

    Beta-toxin (CPB) is the essential virulence factor of C. perfringens type C causing necrotizing enteritis (NE) in different hosts. Using a pig infection model, we showed that CPB targets small intestinal endothelial cells. Its effect on the porcine intestinal epithelium, however, could not be adequately investigated by this approach. Using porcine neonatal jejunal explants and cryosections, we performed in situ binding studies with CPB. We confirmed binding of CPB to endothelial but could not detect binding to epithelial cells. In contrast, the intact epithelial layer inhibited CPB penetration into deeper intestinal layers. CPB failed to induce cytopathic effects in cultured polarized porcine intestinal epithelial cells (IPEC-J2) and primary jejunal epithelial cells. C. perfringens type C culture supernatants were toxic for cell cultures. This, however, was not inhibited by CPB neutralization. Our results show that, in the porcine small intestine, CPB primarily targets endothelial cells and does not bind to epithelial cells. An intact intestinal epithelial layer prevents CPB diffusion into underlying tissue and CPB alone does not cause direct damage to intestinal epithelial cells. Additional factors might be involved in the early epithelial damage which is needed for CPB diffusion towards its endothelial targets in the small intestine. PMID:25860161

  19. The Bacterial Virulence Factor Lymphostatin Compromises Intestinal Epithelial Barrier Function by Modulating Rho GTPases

    PubMed Central

    Babbin, Brian A.; Sasaki, Maiko; Gerner-Schmidt, Kirsten W.; Nusrat, Asma; Klapproth, Jan-Michael A.

    2009-01-01

    Lymphocyte inhibitory factor A (lifA) in Citrobacter rodentium encodes the large toxin lymphostatin, which contains two enzymatic motifs associated with bacterial pathogenesis, a glucosyltransferase and a protease. Our aim was to determine the effects of each lymphostatin motif on intestinal epithelial-barrier function. In-frame mutations of C. rodentium lifA glucosyltransferase (CrGlM21) and protease (CrPrM5) were generated by homologous recombination. Infection of both model intestinal epithelial monolayers and mice with C. rodentium wild type resulted in compromised epithelial barrier function and mislocalization of key intercellular junction proteins in the tight junction and adherens junction. In contrast, CrGlM21 was impaired in its ability to reduce barrier function and influenced the tight junction proteins ZO-1 and occludin. CrPrM5 demonstrated decreased effects on the adherens junction proteins β-catenin and E-cadherin. Analysis of the mechanisms revealed that C. rodentium wild type differentially influenced Rho GTPase activation, suppressed Cdc42 activation, and induced Rho GTPase activation. CrGlM21 lost its suppressive effects on Cdc42 activation, whereas CrPrM5 was unable to activate Rho signaling. Rescue experiments using constitutively active Cdc42 or C3 exotoxin to inhibit Rho GTPase supported a role of Rho GTPases in the epithelial barrier compromise induced by C. rodentium. Taken together, our results suggest that lymphostatin is a bacterial virulence factor that contributes to the disruption of intestinal epithelial-barrier function via the modulation of Rho GTPase activities. PMID:19286565

  20. Mycotoxins Deoxynivalenol and Fumonisins Alter the Extrinsic Component of Intestinal Barrier in Broiler Chickens.

    PubMed

    Antonissen, Gunther; Van Immerseel, Filip; Pasmans, Frank; Ducatelle, Richard; Janssens, Geert P J; De Baere, Siegrid; Mountzouris, Konstantinos C; Su, Shengchen; Wong, Eric A; De Meulenaer, Bruno; Verlinden, Marc; Devreese, Mathias; Haesebrouck, Freddy; Novak, Barbara; Dohnal, Ilse; Martel, An; Croubels, Siska

    2015-12-23

    Deoxynivalenol (DON) and fumonisins (FBs) are secondary metabolites produced by Fusarium fungi that frequently contaminate broiler feed. The aim of this study was to investigate the impact of DON and/or FBs on the intestinal barrier in broiler chickens, more specifically on the mucus layer and antioxidative response to oxidative stress. One-day-old broiler chicks were divided into four groups, each consisting of eight pens of seven birds each, and were fed for 15 days either a control diet, a DON-contaminated diet (4.6 mg DON/kg feed), a FBs-contaminated diet (25.4 mg FB1 + FB2/kg feed), or a DON+FBs-contaminated diet (4.3 mg DON and 22.9 mg FB1 + FB2/kg feed). DON and FBs affected the duodenal mucus layer by suppressing intestinal mucin (MUC) 2 gene expression and altering the mucin monosaccharide composition. Both mycotoxins decreased gene expression of the intestinal zinc transporter (ZnT)-1 and regulated intracellular methionine homeostasis, which are both important for preserving the cell's critical antioxidant activity. Feeding a DON- and/or FBs-contaminated diet, at concentrations close to the European Union maximum guidance levels (5 mg DON and 20 mg FB1 + FB2/kg feed) changes the intestinal mucus layer and several intestinal epithelial antioxidative mechanisms.

  1. Delivery of a mucin domain enriched in cysteine residues strengthens the intestinal mucous barrier

    PubMed Central

    Gouyer, Valérie; Dubuquoy, Laurent; Robbe-Masselot, Catherine; Neut, Christel; Singer, Elisabeth; Plet, Ségolène; Geboes, Karel; Desreumaux, Pierre; Gottrand, Frédéric; Desseyn, Jean-Luc

    2015-01-01

    A weakening of the gut mucous barrier permits an increase in the access of intestinal luminal contents to the epithelial cells, which will trigger the inflammatory response. In inflammatory bowel diseases, there is an inappropriate and ongoing activation of the immune system, possibly because the intestinal mucus is less protective against the endogenous microflora. General strategies aimed at improving the protection of the intestinal epithelium are still missing. We generated a transgenic mouse that secreted a molecule consisting of 12 consecutive copies of a mucin domain into its intestinal mucus, which is believed to modify the mucus layer by establishing reversible interactions. We showed that the mucus gel was more robust and that mucin O-glycosylation was altered. Notably, the gut epithelium of transgenic mice housed a greater abundance of beneficial Lactobacillus spp. These modifications were associated with a reduced susceptibility of transgenic mice to chemically induced colitis. Furthermore, transgenic mice cleared faster Citrobacter rodentium bacteria which were orally given and mice were more protected against bacterial translocation induced by gavage with adherent–invasive Escherichia coli. Our data show that delivering the mucin CYS domain into the gut lumen strengthens the intestinal mucus blanket which is impaired in inflammatory bowel diseases. PMID:25974250

  2. Boswellia serrata Preserves Intestinal Epithelial Barrier from Oxidative and Inflammatory Damage.

    PubMed

    Catanzaro, Daniela; Rancan, Serena; Orso, Genny; Dall'Acqua, Stefano; Brun, Paola; Giron, Maria Cecilia; Carrara, Maria; Castagliuolo, Ignazio; Ragazzi, Eugenio; Caparrotta, Laura; Montopoli, Monica

    2015-01-01

    Aminosalicylates, corticosteroids and immunosuppressants are currently the therapeutic choices in inflammatory bowel diseases (IBD), however, with limited remission and often serious side effects. Meanwhile complementary and alternative medicine (CAM) use is increasing, particularly herbal medicine. Boswellia serrata is a traditional Ayurvedic remedy with anti-inflammatory properties, of interest for its usefulness in IBDs. The mechanism of this pharmacological potential of Boswellia serrata was investigated in colonic epithelial cell monolayers exposed to H2O2 or INF-γ+TNF-α, chosen as in vitro experimental model of intestinal inflammation. The barrier function was evaluated by the transepithelial electrical resistance (TEER) and paracellular permeability assay, and by the tight junction proteins (zonula occludens-1, ZO-1 and occludin) immunofluorescence. The expression of phosphorylated NF-κB and reactive oxygen species (ROS) generation were determined by immunoblot and cytofluorimetric assay, respectively. Boswellia serrata oleo-gum extract (BSE) and its pure derivative acetyl-11-keto-β-boswellic acid (AKBA), were tested at 0.1-10 μg/ml and 0.027 μg/ml, respectively. BSE and AKBA safety was demonstrated by no alteration of intestinal cell viability and barrier function and integrity biomarkers. H2O2 or INF-γ+TNF-α treatment of Caco-2 cell monolayers significantly reduced TEER, increased paracellular permeability and caused the disassembly of tight junction proteins occludin and ZO-1. BSE and AKBA pretreatment significantly prevented functional and morphological alterations and also the NF-κB phosphorylation induced by the inflammatory stimuli. At the same concentrations BSE and AKBA counteracted the increase of ROS caused by H2O2 exposure. Data showed the positive correlation of the antioxidant activity with the mechanism involved in the physiologic maintenance of the integrity and function of the intestinal epithelium. This study elucidates the

  3. Boswellia serrata Preserves Intestinal Epithelial Barrier from Oxidative and Inflammatory Damage

    PubMed Central

    Catanzaro, Daniela; Rancan, Serena; Orso, Genny; Dall’Acqua, Stefano; Brun, Paola; Giron, Maria Cecilia; Carrara, Maria; Castagliuolo, Ignazio; Ragazzi, Eugenio; Caparrotta, Laura; Montopoli, Monica

    2015-01-01

    Aminosalicylates, corticosteroids and immunosuppressants are currently the therapeutic choices in inflammatory bowel diseases (IBD), however, with limited remission and often serious side effects. Meanwhile complementary and alternative medicine (CAM) use is increasing, particularly herbal medicine. Boswellia serrata is a traditional Ayurvedic remedy with anti-inflammatory properties, of interest for its usefulness in IBDs. The mechanism of this pharmacological potential of Boswellia serrata was investigated in colonic epithelial cell monolayers exposed to H2O2 or INF-γ+TNF-α, chosen as in vitro experimental model of intestinal inflammation. The barrier function was evaluated by the transepithelial electrical resistance (TEER) and paracellular permeability assay, and by the tight junction proteins (zonula occludens-1, ZO-1 and occludin) immunofluorescence. The expression of phosphorylated NF-κB and reactive oxygen species (ROS) generation were determined by immunoblot and cytofluorimetric assay, respectively. Boswellia serrata oleo-gum extract (BSE) and its pure derivative acetyl-11-keto-β-boswellic acid (AKBA), were tested at 0.1-10 μg/ml and 0.027μg/ml, respectively. BSE and AKBA safety was demonstrated by no alteration of intestinal cell viability and barrier function and integrity biomarkers. H2O2 or INF-γ+TNF-α treatment of Caco-2 cell monolayers significantly reduced TEER, increased paracellular permeability and caused the disassembly of tight junction proteins occludin and ZO-1. BSE and AKBA pretreatment significantly prevented functional and morphological alterations and also the NF-κB phosphorylation induced by the inflammatory stimuli. At the same concentrations BSE and AKBA counteracted the increase of ROS caused by H2O2 exposure. Data showed the positive correlation of the antioxidant activity with the mechanism involved in the physiologic maintenance of the integrity and function of the intestinal epithelium. This study elucidates the

  4. Effect of γ-aminobutyric acid on digestive enzymes, absorption function, and immune function of intestinal mucosa in heat-stressed chicken.

    PubMed

    Chen, Z; Xie, J; Wang, B; Tang, J

    2014-10-01

    To explore the effect of dietary γ-aminobutyric acid (GABA) on digestive enzyme activity, absorption function and immune function of intestinal mucosa in heat-stressed Wenchang chicken were studied. One-day-old male Wenchang chickens were randomly divided into a control group (CK), heat stress group (HS), and GABA+HS group. The chickens from the GABA+HS group were administered with 0.2 mL of GABA solution daily. Chickens from HS and GABA+HS groups were subjected to heat stress treatment at 40 ± 0.5°C for 2 h during 1300 to 1500 h every day. Blood was drawn and 0.5 cm-long duodenum, jejunum, and ileum were collected from the chickens on d 3, 5, 7, 9, 12, and 15. Results showed that the activity of Ca²⁺-Mg²⁺-adenosine triphosphatase (ATPase), Na⁺-K⁺-ATPase, maltase, sucrase, and alkaline phosphatase, the contents of secretory IgA, glutathione, and d-xylose, and the number of lymphocytes in HS group were significantly lower than those in the CK group. Among them, some were rescued after the treatment of GABA as the time extension. For maltase, d-xylose, alkaline phosphatase, and Na⁺-K⁺-ATPase, it required 5 to 7 d for achieving the significant effect. For sucrase, 12 d for the alleviation effect was required. In the case of other parameters, no alleviation was observed during the whole period of the study. We have concluded that HS can inhibit the activity of digestive enzymes and reduce absorption and immune functions of intestinal mucosa. γ-Aminobutyric acid can effectively alleviate these inhibitory effects.

  5. Effect of vitamin A deficiency on permeability of the small intestinal mucosa for macromolecules in adult rats

    SciTech Connect

    Gmoshinskii, I.V.; Khvylya, S.I.; Kon', I.Ya.

    1987-07-01

    The authors study the effect of experimental vitamin A deficiency on absorption of macromolecules of hen's ovalbumin in the intestine. An electron-microscopic study of permeability of small intestine enterocytes for particles of colloidal lanthanum hydroxide La(OH)/sub 3/ was carried out at the same time. The concentration of unsplit hen's ovalbumin in the blood of the rats used in the experiment was determined by competitive radioimmunoassay. Samples of serum were incubated with indicator doses of /sup 125/I-OA. Radioactivity of the precipitates was measured.

  6. Lactobacillus protects the integrity of intestinal epithelial barrier damaged by pathogenic bacteria

    PubMed Central

    Yu, Qinghua; Yuan, Lixia; Deng, Jun; Yang, Qian

    2015-01-01

    Pathogens invade intestinal mucosal barrier through phagocytosis of antigen presenting cells (dendritic cell, microfold cells), or through the invasion into the intestinal epithelial directly. Some pathogens could damage the cell junction between epithelial cells and use the paracellular pathway as an entrance to invade. Moreover, some Lactobacillus could inhibit the adhesion of the pathogens and protect the integrity of the cell junction and mucosal barrier. This research focused on the potential therapeutic effect of Lactobacillus fructosus (L. fructosus) C2 to attenuate ETEC K88 or S. typhimurium SL1344 induced changes to mucosal barrier. The results demonstrated that treatment of polarized Caco-2 cells with L. fructosus C2 reduced the permeation of dextran, and expression of IL-8, p-ERK, and p-JNK when cells were infected with pathogenic bacteria. The findings indicated that L. fructosus C2 exerted a protective effect against the damage to the integrity of Caco-2 cells by ETEC or S. typhimurium infection. PMID:25859435

  7. Protein kinase C δ signaling is required for dietary prebiotic-induced strengthening of intestinal epithelial barrier function

    PubMed Central

    Wu, Richard Y.; Abdullah, Majd; Määttänen, Pekka; Pilar, Ana Victoria C.; Scruten, Erin; Johnson-Henry, Kathene C.; Napper, Scott; O’Brien, Catherine; Jones, Nicola L.; Sherman, Philip M.

    2017-01-01

    Prebiotics are non-digestible oligosaccharides that promote the growth of beneficial gut microbes, but it is unclear whether they also have direct effects on the intestinal mucosal barrier. Here we demonstrate two commercial prebiotics, inulin and short-chain fructo-oligosaccharide (scFOS), when applied onto intestinal epithelia in the absence of microbes, directly promote barrier integrity to prevent pathogen-induced barrier disruptions. We further show that these effects involve the induction of select tight junction (TJ) proteins through a protein kinase C (PKC) δ-dependent mechanism. These results suggest that in the absence of microbiota, prebiotics can directly exert barrier protective effects by activating host cell signaling in the intestinal epithelium, which represents a novel alternative mechanism of action of prebiotics. PMID:28098206

  8. Anti-mouse CD52 monoclonal antibody ameliorates intestinal epithelial barrier function in interleukin-10 knockout mice with spontaneous chronic colitis.

    PubMed

    Wang, Honggang; Dong, Jianning; Shi, Peiliang; Liu, Jianhui; Zuo, Lugen; Li, Yi; Gong, Jianfeng; Gu, Lili; Zhao, Jie; Zhang, Liang; Zhang, Wei; Zhu, Weiming; Li, Ning; Li, Jieshou

    2015-02-01

    Intestinal inflammation causes tight junction changes and death of epithelial cells, and plays an important role in the development of Crohn's disease (CD). CD52 monoclonal antibody (CD52 mAb) directly targets the cell surface CD52 and is effective in depleting mature lymphocytes by cytolytic effects in vivo, leading to long-lasting changes in adaptive immunity. The aim of this study was to investigate the therapeutic effect of CD52 mAb on epithelial barrier function in animal models of IBD. Interleukin-10 knockout mice (IL-10(-/-) ) of 16 weeks with established colitis were treated with CD52 mAb once a week for 2 weeks. Severity of colitis, CD4(+) lymphocytes and cytokines in the lamina propria, epithelial expression of tight junction proteins, morphology of tight junctions, tumour necrosis factor-α (TNF-α)/TNF receptor 2 (TNFR2) mRNA expression, myosin light chain kinase (MLCK) expression and activity, as well as epithelial apoptosis in proximal colon were measured at the end of the experiment. CD52 mAb treatment effectively attenuated colitis associated with decreased lamina propria CD4(+) lymphocytes and interferon-γ/IL-17 responses in colonic mucosa in IL-10(-/-) mice. After CD52 mAb treatment, attenuation of colonic permeability, increased epithelial expression and correct localization of tight junction proteins (occludin and zona occludens protein-1), as well as ameliorated tight junction morphology were observed in IL-10(-/-) mice. CD52 mAb treatment also effectively suppressed the epithelial apoptosis, mucosa TNF-α mRNA expression, epithelial expression of long MLCK, TNFR2 and phosphorylation of MLC. Our results indicated that anti-CD52 therapy may inhibit TNF-α/TNFR2-mediated epithelial apoptosis and MLCK-dependent tight junction permeability by depleting activated T cells in the gut mucosa.

  9. Stress-induced breakdown of intestinal barrier function in the rat: reversal by wood creosote.

    PubMed

    Kuge, Tomoo; Greenwood-Van Meerveld, Beverley; Sokabe, Masahiro

    2006-07-24

    Our previous studies demonstrated that wood creosote (Seirogan) inhibits intestinal secretion and normalizes the transport of electrolytes and water in rats subjected to restraint stress. The goal of the present study was to examine whether wood creosote has a protective effect against stress-induced breakdown of intestinal barrier function. F-344 rats were subjected to 90-min water avoidance stress (WAS) with wood creosote (30 mg/kg) or vehicle administered intragastrically 30 min prior to WAS. Sham stressed rats received wood creosote or vehicle treatment but did not experience the WAS. All rats were euthanized at the end of the WAS or sham-stress and the jejunum and colon were isolated. Epithelial transport was studied in modified Ussing chambers. Spontaneous secretion was assessed by electrophysiological measurement of the short circuit current (I(sc)) while electrical conductance (G) was calculated from the potential difference (PD) and I(sc) using Ohm's law. Intestinal permeability was defined by the mucosal-to-serosal flux of horseradish peroxidase (HRP). WAS significantly elevated basal I(sc) and G and increased epithelial permeability to HRP in the jejunum but not in the colon. Wood creosote resulted in a significant reduction of the stress-induced increase in I(sc), G and the mucosal-to-serosal flux of HRP compared to the vehicle-treated group. Wood creosote caused no significant effects in sham-stressed rats. The results suggest that oral administration of wood creosote may prevent stress-induced diarrhea by preventing aversive effects on small intestinal secretion and barrier function.

  10. Human intestinal mucosa-associated Lactobacillus and Bifidobacterium strains with probiotic properties modulate IL-10, IL-6 and IL-12 gene expression in THP-1 cells.

    PubMed

    Čitar, M; Hacin, B; Tompa, G; Štempelj, M; Rogelj, I; Dolinšek, J; Narat, M; Matijašić, B Bogovič

    2015-01-01

    Lactobacilli and bifidobacteria are considered one of the permanent genera of the physiological human intestinal microbiota and represent an enormous pool of potential probiotic candidates. Approximately 450 isolates of presumptive Lactobacillus or Bifidobacterium strains were obtained from bioptic samples of colonic and ileal mucosa from 15 adolescents aged 12 to 18 years. On the basis of randomly amplified polymorphic DNA (RAPD)-PCR analysis, 20 strains were selected for further taxonomic classification and characterisation, as well as assessment of probiotic properties and safety. Importantly, selected strains showed the capability of colonising different parts of the intestine. The most frequently isolated species was Lactobacillus paracasei followed by Lactobacillus fermentum. The majority of isolates were susceptible to antimicrobials of human and veterinary importance, however, tetracycline and/or erythromycin resistance was observed in Lactobacillus plantarum and L. fermentum strains. Thirteen strains were able to ferment more than 19 different carbon sources and three out of five tested strains exerted antagonistic activity against several different indicator strains. Two Lactobacillus isolates (L. paracasei L350 and L. fermentum L930 bb) and one Bifidobacterium isolate (Bifidobacterium animalis subsp. animalis IM386) fulfilled in vitro selection criteria for probiotic strains and exhibited strong downregulation of pro-inflammatory cytokines IL-6 and IL-12 and upregulation of anti-inflammatory IL-10. The selected strains represent suitable candidates for further studies regarding their positive influence on host health and could play an important role in ameliorating the symptoms of inflammatory bowel diseases.

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

    SciTech Connect

    Shim, Sehwan; Lee, Jong-geol; Bae, Chang-hwan; Lee, Seung Bum; Jang, Won-Suk; Lee, Sun-Joo; Lee, Seung-Sook; Park, Sunhoo

    2015-01-02

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

  12. Bifidobacteria Prevent Tunicamycin-Induced Endoplasmic Reticulum Stress and Subsequent Barrier Disruption in Human Intestinal Epithelial Caco-2 Monolayers

    PubMed Central

    Akiyama, Takuya; Oishi, Kenji

    2016-01-01

    Endoplasmic reticulum (ER) stress is caused by accumulation of unfolded and misfolded proteins in the ER, thereby compromising its vital cellular functions in protein production and secretion. Genome wide association studies in humans as well as experimental animal models linked ER stress in intestinal epithelial cells (IECs) with intestinal disorders including inflammatory bowel diseases. However, the mechanisms linking the outcomes of ER stress in IECs to intestinal disease have not been clarified. In this study, we investigated the impact of ER stress on intestinal epithelial barrier function using human colon carcinoma-derived Caco-2 monolayers. Tunicamycin-induced ER stress decreased the trans-epithelial electrical resistance of Caco-2 monolayers, concomitant with loss of cellular plasma membrane integrity. Epithelial barrier disruption in Caco-2 cells after ER stress was not caused by caspase- or RIPK1-dependent cell death but was accompanied by lysosomal rupture and up-regulation of the ER stress markers Grp78, sXBP1 and Chop. Interestingly, several bifidobacteria species inhibited tunicamycin-induced ER stress and thereby diminished barrier disruption in Caco-2 monolayers. Together, these results showed that ER stress compromises the epithelial barrier function of Caco-2 monolayers and demonstrate beneficial impacts of bifidobacteria on ER stress in IECs. Our results identify epithelial barrier loss as a potential link between ER stress and intestinal disease development, and suggest that bifidobacteria could exert beneficial effects on this phenomenon. PMID:27611782

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

    PubMed Central

    Raymond, Arthur; Mercade-Loubière, Myriam; Salvador-Cartier, Christel; Ringot, Bélinda; Léonard, Renaud; Fourquaux, Isabelle; Ait-Belgnaoui, Afifa; Loubière, Pascal; Théodorou, Vassilia; Mercier-Bonin, Muriel

    2015-01-01

    The present study aimed at detecting the exogenously applied probiotic Lactobacillus farciminis in rats, after exposure to IBS-like chronic stress, based on 4-day Water Avoidance Stress (WAS). The presence of L. farciminis in both ileal and colonic mucosal tissues was demonstrated by FISH and qPCR, with ileum as the preferential niche, as for the SFB population. A different spatial distribution of the probiotic was observed: in the ileum, bacteria were organized in micro-colonies more or less close to the epithelium whereas, in the colon, they were mainly visualized far away from the epithelium. When rats were submitted to WAS, the L. farciminis population substantially decreased in both intestinal regions, due to a stress-induced increase in colonic motility and defecation, rather than a modification of bacterial binding to the intestinal mucin Muc2. PMID:26367538

  14. Temporal and spatial interplay of microbiota and intestinal mucosa drive establishment of immune homeostasis in conventionalized mice.

    PubMed

    El Aidy, Sahar; van Baarlen, Peter; Derrien, Muriel; Lindenbergh-Kortleve, Dicky J; Hooiveld, Guido; Levenez, Florence; Doré, Joël; Dekker, Jan; Samsom, Janneke N; Nieuwenhuis, Edward E S; Kleerebezem, Michiel

    2012-09-01

    During colonization of germfree mice with the total fecal microbial community of their conventionally born and raised siblings (conventionalization), the intestinal mucosal immune system initiates and maintains a balanced immune response. However, the genetic regulation of these balanced, appropriate responses to the microbiota is obscure. Here, combined analysis of germfree and conventionalized mice revealed that the major molecular responses could be detected initiating at day 4 post conventionalization, with a strong induction of innate immune functions followed by stimulation of adaptive immune responses and development and expansion of adaptive immune cells at later stages of conventionalization. This study provides a comprehensive overview of mouse developmental and immune-related cellular pathways and processes that were co-mediated by the commensal microbiota and suggests which mechanisms were involved in this reprogramming. The dynamic, region-dependent mucosal responses to the colonizing microbiota revealed potential transcriptional signatures for the control of intestinal homeostasis in healthy mice, which may help to decipher the genetic basis of pathway dysregulation in human intestinal inflammatory diseases.

  15. Nitric oxide attenuates hydrogen peroxide-induced barrier disruption and protein tyrosine phosphorylation in monolayers of intestinal epithelial cell.

    PubMed

    Katsube, Takanori; Tsuji, Hideo; Onoda, Makoto

    2007-06-01

    The intestinal epithelium provides a barrier to the transport of harmful luminal molecules into the systemic circulation. A dysfunctional epithelial barrier is closely associated with the pathogenesis of a variety of intestinal and systemic disorders. We investigated here the effects of nitric oxide (NO) and hydrogen peroxide (H(2)O(2)) on the barrier function of a human intestinal epithelial cell line, Caco-2. When treated with H(2)O(2), Caco-2 cell monolayers grown on permeable supports exhibited several remarkable features of barrier dysfunction as follows: a decrease in transepithelial electrical resistance, an increase in paracellular permeability to dextran, and a disruption of the intercellular junctional localization of the scaffolding protein ZO-1. In addition, an induction of tyrosine phosphorylation of numerous cellular proteins including ZO-1, E-cadherin, and beta-catenin, components of tight and adherens junctions, was observed. On the other hand, combined treatment of Caco-2 monolayers with H(2)O(2) and an NO donor (NOC5 or NOC12) relieved the damage to the barrier function and suppressed the protein tyrosine phosphorylation induced by H(2)O(2) alone. These results suggest that NO protects the barrier function of intestinal epithelia from oxidative stress by modulating some intracellular signaling pathways of protein tyrosine phosphorylation in epithelial cells.

  16. Low Dosage of Chitosan Supplementation Improves Intestinal Permeability and Impairs Barrier Function in Mice

    PubMed Central

    Peng, Hanhui; Li, Guanya

    2016-01-01

    The purpose of this study was to explore relationships between low dose dietary supplementation with chitosan (COS) and body weight, feed intake, intestinal barrier function, and permeability in mice. Twenty mice were randomly assigned to receive an unadulterated control diet (control group) or a dietary supplementation with 30 mg/kg dose of chitosan (COS group) for two weeks. Whilst no significant differences were found between the conditions for body weight or food and water intake, mice in the COS group had an increased serum D-lactate content (P < 0.05) and a decreased jejunal diamine oxidase (DAO) activity (P < 0.05). Furthermore, mice in COS group displayed a reduced expression of occludin and ZO-1 (P < 0.05) and a reduced expression of occludin in the ileum (P < 0.05). The conclusion drawn from these findings showed that although 30 mg/kg COS-supplemented diet had no effect on body weight or feed intake in mice, this dosage may compromise intestinal barrier function and permeability. This research will contribute to the guidance on COS supplements. PMID:27610376

  17. Protective effect of salvianolic acid B on NASH rat liver through restoring intestinal mucosal barrier function

    PubMed Central

    Wang, Ying-Chun; Jin, Qing-Mei; Kong, Wei-Zong; Chen, Juan

    2015-01-01

    Aim: To investigate the effect of Salvianolic acid B (Sal B) on the disease progress of NASH and change of intestinal barrier function. Methods: Sixty Sprague-Dawley (SD) rats were randomly divided into control group, model group and treated group, with the former given normal diet and the latter 2 groups rats fed high-fat diet. In treated group, rats were infused through the stomach with 1 mg/ml Sal B every day at a dose of 20 mL/kg body weight. All animals were killed at the 24th week and plasma levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), triglyceride (TG), total cholesterol (TC), endotoxin (ET) and diamine oxdase (DAO) were analyzed using the blood samples. The histopathology of liver was observed by H&E staining. The expression changes of tight junction protein occludin and ZO-1 were analyzed by immunocytochemistry. Ultrastructural morphology of small intestinal tissues was investigated by transmission electron microscopy. Results: Plasma levels of ALT, AST, TG, TC, ET and DAO were significantly higher in model group than those in both control group and group treated with Sal B. In model group, vacuolated swelling of the cytoplasm with aggregates of chronic inflammatory cells was observed in the liver tissue but not in Sal B-treated group. NAFLD Activity Score in the treated group was significantly lower than that in model group. Immunohistochemical staining showed that Sal B administration recovered the expression of occludin and ZO-1, which was downregulated in the model group. Transmission electron microscopy analysis demonstrated that cell surface microvilli and major intercellular junctional complex including tight junction, gap junction and adherens junction were restored in Sal B-treated group. Conclusion: Sal B exerted protective function against high-fat diet-induced liver damage by restoring healthy barrier function of intestine in NASH rat model. PMID:26191218

  18. Nickel-Related Intestinal Mucositis in IBS-Like Patients: Laser Doppler Perfusion Imaging and Oral Mucosa Patch Test in Use.

    PubMed

    Borghini, Raffaele; Puzzono, Marta; Rosato, Edoardo; Di Tola, Marco; Marino, Mariacatia; Greco, Francesca; Picarelli, Antonio

    2016-09-01

    Nickel (Ni) is often the trigger of irritable bowel syndrome (IBS)-like gastrointestinal disorders: its ingestion may cause allergic contact mucositis, identifiable by means of oral mucosa patch test (omPT). OmPT effectiveness has been proven, but it is still an operator-dependent method. Laser Doppler perfusion imaging (LDPI) was tested to support omPT in Ni allergic contact mucositis diagnosis. Group A: 22 patients with intestinal/systemic symptoms related to the ingestion of Ni-containing foods. Group B: 12 asymptomatic volunteers. Ni-related symptoms and their severity were tested by a questionnaire. All patients underwent Ni omPT with clinical evaluation at baseline (T0), after 30 min (T1), after 2 h (T2), and after 24-48 h (T3). LDPI was performed to evaluate the mean mucosal perfusion at T0, T1, and T2. Statistical analysis was performed by ANOVA test and Bonferroni multiple-comparison test. All 22 Ni-sensitive patients (group A) presented oral mucosa hyperemia and/or edema at T2. Eight out of the same 22 patients presented a local delayed vesicular reaction at T3 (group A1), unlike the remaining 14 out of 22 patients (group A2). All 12 patients belonging to control group B did not show any alteration. The mean mucosal perfusion calculated with LDPI showed an increase in both subgroups A1 and A2. In group B, no significant perfusion variations were observed. LDPI may support omPT for diagnostic purposes in Ni allergic contact mucositis. This also applies to symptomatic Ni-sensitive patients without aphthous stomatitis after 24-48 h from omPT and that could risk to miss the diagnosis.

  19. Contributions of altered permeability of intestinal barrier and defecation behavior to toxicity formation from graphene oxide in nematode Caenorhabditis elegans.

    PubMed

    Wu, Qiuli; Yin, Li; Li, Xing; Tang, Meng; Zhang, Tao; Wang, Dayong

    2013-10-21

    Graphene oxide (GO) has been extensively studied for potential biomedical applications. Meanwhile, potential GO toxicity arises in both biomedical applications and non-biomedical products where environmental exposures may occur. In the present study, we examined the potential adverse effects of GO and the underlying mechanism using nematode Caenorhabditis elegans as the assay system. We compared the in vivo effects of GO between acute exposure and prolonged exposure, and found that prolonged exposure to 0.5-100 mg L(-1) of GO caused damage on functions of both primary (intestine) and secondary (neuron and reproductive organ) targeted organs. In the intestine, ROS production was significantly correlated with the formation of adverse effects on functions of both primary and secondary targeted organs. GO could be translocated into intestinal cells with loss of microvilli, and distributed to be adjacent to or surrounding mitochondria. Prolonged exposure to GO resulted in a hyper-permeable state of the intestinal barrier, an increase in mean defecation cycle length, and alteration of genes required for intestinal development and defecation behavior. Thus, our data suggest that prolonged exposure to GO may cause potential risk to environmental organisms after release into the environment. GO toxicity may be due to the combinational effects of oxidative stress in the intestinal barrier, enhanced permeability of the biological barrier, and suppressed defecation behavior in C. elegans.

  20. Characteristics of β-galactosidase in the mucosa of the small intestine of infant rats. Physicochemical properties

    PubMed Central

    Kraml, Jiří; Koldovský, Otakar; Heringová, Aleša; Jirsová, Věra; Kácl, Karel; Ledvina, Miloš; Pelichová, Hana

    1969-01-01

    1. The characteristics of acid and neutral β-galactosidases isolated chromatographically from homogenates of the mucosa of the jejunum and ileum of suckling rats were studied. 2. The minimal molecular weight of the acid β-galactosidase, as estimated by gel filtration on Sephadex G-200, was in the range 83000–105000, whereas for the neutral β-galactosidase the estimated molecular weight was in the range 360000–510000. 3. The acid and neutral β-galactosidases were inhibited competitively by galactono-(1→4)-lactone, with respective Ki values of 0·15mm and 1·1mm. Only the acid β-galactosidase was inhibited competitively by sodium galactonate (Ki 0·17mm). 4. Heat inactivation of both β-galactosidases occurred according to first-order kinetics. The neutral enzyme was more labile, but bovine serum albumin protected acid enzyme only. 5. Urea treatment inactivated both β-galactosidases, the neutral β-galactosidase being more sensitive than the acid β-galactosidase. 6. No differences were found between preparations from the jejunum and ileum. PMID:5820646

  1. Effect of eicosapentaenoic acid-derived prostaglandin E3 on intestinal epithelial barrier function.

    PubMed

    Rodríguez-Lagunas, Maria J; Ferrer, Ruth; Moreno, Juan J

    2013-05-01

    Prostaglandins (PG) are inflammatory mediators derived from arachidonic or eicosapentaenoic acid giving rise to the 2-series or the 3-series prostanoids, respectively. Previously, we have observed that PGE2 disrupts epithelial barrier function. Considering the beneficial effect of fish oil consumption in intestinal inflammatory processes, the aim of this study was to assess the role of PGE3 on epithelial barrier function assessed from transepithelial electrical resistance and dextran fluxes in Caco-2 cells. The results indicate that PGE3 increased paracellular permeability (PP) to the same extent as PGE2, through the interaction with EP1 and EP4 receptors and with intracellular Ca(2+) and cAMP as the downstream targets. Moreover, we observed a redistribution of tight junction proteins, occludin and claudin-4. In conclusion, PGE3 is able to increase PP thus leading to reconsider the role of PGE2/PGE3 ratio in the beneficial effects of dietary fish oil supplementation in the disruption of barrier function.

  2. Protective effect of Enterococcus faecalis DAPTO 512 on the intestinal tract and gut mucosa: milk allergy application.

    PubMed

    Belkaaloul, K; Haertlé, T; Chobert, J M; Merah, R; Taibi, K; Saad El Hachemi, H A; Hemch, S; Amier, L; Chekroun, A; Saidi, D; Kheroua, O

    2015-01-01

    The allergenicity of β-lactoglobulin (β-Lg) was studied by using Ussing chamber in a murine model of β-Lg allergy supplemented with hydrolysates obtained after fermentation of milk for 48 h at 37 (°)C with Enterococcus faecalis DAPTO 512, isolated from cow milk and identified by 16S rDNA sequence analysis. Balb/c mice were sensitised intraperitoneally with β-Lg. Three groups of mice were formed: group 1, composed of naive mice used as control received only NaCl; group 2, positive control composed of mice sensitised intraperitoneally with β-Lg; group 3, formed by mice which were given hydrolysates of 48 h then sensitised with β-Lg. After 48 h of fermentation β-casein and β-Lg were degraded by E. faecalis DAPTO 512. β-Lg immunisation was associated with strong IgG and IgE production in case of positive controls and a significant increase in short current circuit (Isc) and high conductance (G) responses were observed. The control and the hydrolysate groups showed a significant decrease in the production of IgG and IgE anti β-Lg compared to the positive control. The allergenic potential of β-Lg was markedly reduced in the group that received hydrolysates (Isc and G remained unchanged after intestine challenge with β-Lg). The histological scrutiny showed villi atrophy, lymphocyte hyperplasia and a significant chorion detachment in the positive control group. In the group administered with hydrolysates of fermented milk, inflammatory signs were lower, the villi were long and thin and lymphocytes were less dense. The results showed that feeding of milk fermented with E. faecalis DAPTO 512 during 18 days prior to β-Lg allergy induction exerts a protecting effect on the murine intestine and induces a significant decrease in the β-Lg allergenicity.

  3. Phenotypic characterization of cells participating in transport of prion protein aggregates across the intestinal mucosa of sheep

    PubMed Central

    Piercey Åkesson, Caroline; Press, Charles McL.; Tranulis, Michael A.; Jeffrey, Martin; Aleksandersen, Mona; Landsverk, Thor; Espenes, Arild

    2012-01-01

    The oral route is considered to be the main entry site of several transmissible spongiform encephalopathies or prion diseases of animals and man. Following natural and experimental oral exposure to scrapie, sheep first accumulate disease associated prion protein (PrPd) in Peyer’s patch (PP) lymphoid follicles. In this study, recombinant ovine prion protein (rPrP) was inoculated into gut loops of young lambs and the transportation across the intestinal wall studied. In particular, the immunohistochemical phenotypes of cells bearing the inoculated prion protein were investigated. The rPrP was shown to be transported across the villi of the gut, into the lacteals and submucosal lymphatics, mimicking the transport route of PrPd from scrapie brain inoculum observed in a previous intestinal loop experiment. The cells bearing the inoculated rPrP were mainly mononuclear cells, and multicolor immunofluorescence procedures were used to show that the rPrP bearing cells were professional antigen presenting cells expressing Major histocompatibility complex II (MHCII). In addition, the rPrP bearing cells labeled with CD205, CD11b and the macrophage marker CD68, and not with the dendritic cell markers CD11c and CD209. Others have reported that cells expressing CD205 and CD11b in the absence of CD11c have been shown to induce T cell tolerance or regulatory T cells. Based on this association, it was speculated that the rPrP and by extension PrPd and scrapie infective material may exploit the physiological process of macromolecular uptake across the gut, and that this route of entry may have implications for immune surveillance. PMID:22437736

  4. Intentionally induced intestinal barrier dysfunction causes inflammation, affects metabolism, and reduces productivity in lactating Holstein cows.

    PubMed

    Kvidera, S K; Dickson, M J; Abuajamieh, M; Snider, D B; Fernandez, M V Sanz; Johnson, J S; Keating, A F; Gorden, P J; Green, H B; Schoenberg, K M; Baumgard, L H

    2017-03-22

    Study objectives were to evaluate the effects of intentionally reduced intestinal barrier function on productivity, metabolism, and inflammatory indices in otherwise healthy dairy cows. Fourteen lactating Holstein cows (parity 2.6 ± 0.3; 117 ± 18 d in milk) were enrolled in 2 experimental periods. Period 1 (5 d) served as the baseline for period 2 (7 d), during which cows received 1 of 2 i.v. treatments twice per day: sterile saline or a gamma-secretase inhibitor (GSI; 1.5 mg/kg of body weight). Gamma-secretase inhibitors reduce intestinal barrier function by inhibiting crypt cell differentiation into absorptive enterocytes. During period 2, control cows receiving sterile saline were pair-fed (PF) to the GSI-treated cows, and all cows were killed at the end of period 2. Administering GSI increased goblet cell area 218, 70, and 28% in jejunum, ileum, and colon, respectively. In the jejunum, GSI-treated cows had increased crypt depth and reduced villus height, villus height-to-crypt depth ratio, cell proliferation, and mucosal surface area. Plasma lipopolysaccharide binding protein increased with time, and tended to be increased 42% in GSI-treated cows relative to PF controls on d 5 to 7. Circulating haptoglobin and serum amyloid A concentrations increased (585- and 4.4-fold, respectively) similarly in both treatments. Administering GSI progressively reduced dry matter intake (66%) and, by design, the pattern and magnitude of decreased nutrient intake was similar in PF controls. A similar progressive decrease (42%) in milk yield occurred in both treatments, but we observed no treatment effects on milk components. Cows treated with GSI tended to have increased plasma insulin (68%) and decreased circulating nonesterified fatty acids (29%) compared with PF cows. For both treatments, plasma glucose decreased with time while β-hydroxybutyrate progressively increased. Liver triglycerides increased 221% from period 1 to sacrifice in both treatments. No differences were

  5. Partial Enteral Nutrition Preserves Elements of Gut Barrier Function, Including Innate Immunity, Intestinal Alkaline Phosphatase (IAP) Level, and Intestinal Microbiota in Mice

    PubMed Central

    Wan, Xiao; Bi, Jingcheng; Gao, Xuejin; Tian, Feng; Wang, Xinying; Li, Ning; Li, Jieshou

    2015-01-01

    Lack of enteral nutrition (EN) during parenteral nutrition (PN) leads to higher incidence of infection because of gut barrier dysfunction. However, the effects of partial EN on intestina linnate immunity, intestinal alkaline phosphatase (IAP) and microbiota remain unclear. The mice were randomized into six groups to receive either standard chow or isocaloric and isonitrogenous nutritional support with variable partial EN to PN ratios. Five days later, the mice were sacrificed and tissue samples were collected. Bacterial translocation, the levels of lysozyme, mucin 2 (MUC2), and IAP were analyzed. The composition of intestinal microbiota was analyzed by 16S rRNA pyrosequencing. Compared with chow, total parenteral nutrition (TPN) resulted in a dysfunctional mucosal barrier, as evidenced by increased bacterial translocation (p < 0.05), loss of lysozyme, MUC2, and IAP, and changes in the gut microbiota (p < 0.001). Administration of 20% EN supplemented with PN significantly increased the concentrations of lysozyme, MUC2, IAP, and the mRNA levels of lysozyme and MUC2 (p < 0.001). The percentages of Bacteroidetes and Tenericutes were significantly lower in the 20% EN group than in the TPN group (p < 0.001). These changes were accompanied by maintained barrier function in bacterial culture (p < 0.05). Supplementation of PN with 20% EN preserves gut barrier function, by way of maintaining innate immunity, IAP and intestinal microbiota. PMID:26247961

  6. Neutrophil priming by hypoxic preconditioning protects against epithelial barrier damage and enteric bacterial translocation in intestinal ischemia/reperfusion.

    PubMed

    Lu, Yen-Zhen; Wu, Chi-Chin; Huang, Yi-Chen; Huang, Ching-Ying; Yang, Chung-Yi; Lee, Tsung-Chun; Chen, Chau-Fong; Yu, Linda Chia-Hui

    2012-05-01

    Intestinal ischemia/reperfusion (I/R) induces mucosal barrier dysfunction and bacterial translocation (BT). Neutrophil-derived oxidative free radicals have been incriminated in the pathogenesis of ischemic injury in various organs, but their role in the bacteria-containing intestinal tract is debatable. Primed neutrophils are characterized by a faster and higher respiratory burst activity associated with more robust bactericidal effects on exposure to a second stimulus. Hypoxic preconditioning (HPC) attenuates ischemic injury in brain, heart, lung and kidney; no reports were found in the gut. Our aim is to investigate whether neutrophil priming by HPC protects against intestinal I/R-induced barrier damage and bacterial influx. Rats were raised in normoxia (NM) or kept in a hypobaric hypoxic chamber (380 Torr) 17 h/day for 3 weeks for HPC, followed by sham operation or intestinal I/R. Gut permeability was determined by using an ex vivo macromolecular flux assay and an in vivo magnetic resonance imaging-based method. Liver and spleen homogenates were plated for bacterial culturing. Rats raised in HPC showed diminished levels of BT, and partially improved mucosal histopathology and epithelial barrier function compared with the NM groups after intestinal I/R. Augmented cytokine-induced neutrophil chemoattractant (CINC)-1 and -3 levels and myeloperoxidase activity correlated with enhanced infiltration of neutrophils in intestines of HPC-I/R compared with NM-I/R rats. HPC alone caused blood neutrophil priming, as shown by elevated production of superoxide and hydrogen peroxide on stimulation, increased membrane translocation of cytosolic p47(phox) and p67(phox), as well as augmented bacterial-killing and phagocytotic activities. Neutrophil depletion reversed the mucosal protection by HPC, and aggravated intestinal leakiness and BT following I/R. In conclusion, neutrophil priming by HPC protects against I/R-induced BT via direct antimicrobial activity by oxidative

  7. Intestine.

    PubMed

    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.

  8. Ethanol and dietary unsaturated fat (corn oil/linoleic acid enriched) cause intestinal inflammation and impaired intestinal barrier defense in mice chronically fed alcohol.

    PubMed

    Kirpich, Irina A; Feng, Wenke; Wang, Yuhua; Liu, Yanlong; Beier, Juliane I; Arteel, Gavin E; Falkner, K Cameron; Barve, Shirish S; McClain, Craig J

    2013-05-01

    Alcohol and dietary fat both play an important role in alcohol-mediated multi-organ pathology, including gut and liver. In the present study we hypothesized that the combination of alcohol and dietary unsaturated fat (USF) would result in intestinal inflammatory stress and mucus layer alterations, thus contributing to disruption of intestinal barrier integrity. C57BL/6N mice were fed Lieber-DeCarli liquid diets containing EtOH and enriched in USF (corn oil/linoleic acid) or SF (medium chain triglycerides: beef tallow) for 8 weeks. Intestinal histology, morphometry, markers of inflammation, as well as levels of mucus protective factors were evaluated. Alcohol and dietary USF triggered an intestinal pro-inflammatory response, characterized by increase in Tnf-α, MCP1, and MPO activity. Further, alcohol and dietary USF, but not SF, resulted in alterations of the intestinal mucus layer, characterized by decreased expression of Muc2 in the ileum. A strong correlation was observed between down-regulation of the antimicrobial factor Cramp and increased Tnf-α mRNA. Therefore, dietary unsaturated fat (corn oil/LA enriched) is a significant contributing factor to EtOH-mediated intestinal inflammatory response and mucus layer alterations in rodents.

  9. Microbiota and pathogen 'pas de deux': setting up and breaking down barriers to intestinal infection.

    PubMed

    McKenney, Elizabeth S; Kendall, Melissa M

    2016-07-01

    The gut microbiota plays essential roles in human health and disease. In this review, we focus on the role of the intestinal microbiota in promoting resistance to infection by bacterial pathogens as well as how pathogens overcome this barrier. We discuss how the resident microbiota restricts growth and colonization of invading pathogens by limiting availability of nutrients and through generation of a hostile environment. Additionally, we examine how microbiota-derived signaling molecules interfere with bacterial virulence. In turn, we discuss how pathogens exploit non-competitive metabolites to replicate in vivo as well as to precisely control virulence and cause disease. This bacterial two step of creating and overcoming challenges important in preventing and establishing infection highlights the complexities of elucidating interactions between the commensal bacteria and pathogens. Better understanding of microbiota-pathogen interplay will have significant implications for developing novel therapeutics to treat infectious diseases.

  10. Intestinal delivery of non-viral gene therapeutics: physiological barriers and preclinical models.

    PubMed

    O'Neill, Martin J; Bourre, Ludovic; Melgar, Silvia; O'Driscoll, Caitriona M

    2011-03-01

    The future of nucleic acid-based therapeutics is dependent on achieving successful delivery. Recently, there has been an increasing interest in delivery via the gastrointestinal tract. Gene therapy via this route has many advantages, including non-invasive access and the versatility to treat local diseases, such as inflammatory bowel disease, as well as systemic diseases, such as haemophilia. However, the intestine presents several distinct barriers and, therefore, the design of robust non-viral delivery systems is key to future success. Several non-viral delivery strategies have provided evidence of activity in vivo. To facilitate the design of more efficient and safe gene medicines, more physiologically relevant models, at both the in vitro and in vivo levels, are essential.

  11. Intestinal brucellosis associated with celiac artery and superior mesenteric artery stenosis and with ileum mucosa and submucosa thickening

    PubMed Central

    Wang, Miaoqian; Zhu, Qingli; Yang, Qian; Li, Wenbo; Wang, Xinning; Liu, Wei; Zhou, Baotong; Li, Zhenghong; Yang, Hong

    2017-01-01

    Abstract Rationale: Brucellosis is a multisystem infection found worldwide that has a broad range of characteristics, which range from acute fever and hepatomegaly to chronic infections that most commonly affect the central nervous system, cardiovascular system, or skeletal system. Gastrointestinal and splanchnic artery involvements in brucellosis are relatively uncommon. Patient concerns: We report a case of brucellosis in an adolescent presenting as intermittent abdominal pain, diarrhea, and fever, with intestinal tract involvement. And stenosis of the celiac artery and the superior mesenteric artery was found after exposed to risk factors of Brucella infection. Splanchnic vessels stenosis and an endothelial lesion may exacerbate the prevalent symptom of abdominal pain, as a form of colic pain, occurring after eating. Diagnoses: The patient was diagnosed as brucellosis. The narrowing of the SMA and CA was suspected to be vasculitis secondary to the brucellosis. Interventions: The patient was treated with minocycline and rifampicin for 12 weeks totally. Outcomes: The gastrointestinal manifestations of brucellosis recovered rapidly under intensive treatment. However, follow-up imaging revealed that the superior mesenteric artery and celiac artery stenosis was unimproved. Lessons: In brucellosis, gastrointestinal manifestations may be the only observable features of the disease. Splanchnic arterial stenosis is a rare complication of brucellosis. Sonography and computed tomography may be useful for both diagnosis and follow-up. PMID:28079834

  12. Delivery of Berberine Using Chitosan/Fucoidan-Taurine Conjugate Nanoparticles for Treatment of Defective Intestinal Epithelial Tight Junction Barrier

    PubMed Central

    Wu, Shao-Jung; Don, Trong-Ming; Lin, Cheng-Wei; Mi, Fwu-Long

    2014-01-01

    Bacterial-derived lipopolysaccharides (LPS) can cause defective intestinal barrier function and play an important role in the development of inflammatory bowel disease. In this study, a nanocarrier based on chitosan and fucoidan was developed for oral delivery of berberine (Ber). A sulfonated fucoidan, fucoidan-taurine (FD-Tau) conjugate, was synthesized and characterized by Fourier transform infrared (FTIR) spectroscopy. The FD-Tau conjugate was self-assembled with berberine and chitosan (CS) to form Ber-loaded CS/FD-Tau complex nanoparticles with high drug loading efficiency. Berberine release from the nanoparticles had fast release in simulated intestinal fluid (SIF, pH 7.4), while the release was slow in simulated gastric fluid (SGF, pH 2.0). The effect of the berberine-loaded nanoparticles in protecting intestinal tight-junction barrier function against nitric oxide and inflammatory cytokines released from LPS-stimulated macrophage was evaluated by determining the transepithelial electrical resistance (TEER) and paracellular permeability of a model macromolecule fluorescein isothiocyanate-dextran (FITC-dextran) in a Caco-2 cells/RAW264.7 cells co-culture system. Inhibition of redistribution of tight junction ZO-1 protein by the nanoparticles was visualized using confocal laser scanning microscopy (CLSM). The results suggest that the nanoparticles may be useful for local delivery of berberine to ameliorate LPS-induced intestinal epithelia tight junction disruption, and that the released berberine can restore barrier function in inflammatory and injured intestinal epithelial. PMID:25421323

  13. Acute effects of rotavirus and malnutrition on intestinal barrier function in neonatal piglets

    PubMed Central

    Jacobi, Sheila K; Moeser, Adam J; Blikslager, Anthony T; Rhoads, J Marc; Corl, Benjamin A; Harrell, Robert J; Odle, Jack

    2013-01-01

    AIM: To investigate the effect of protein-energy malnutrition on intestinal barrier function during rotavirus enteritis in a piglet model. METHODS: Newborn piglets were allotted at day 4 of age to the following treatments: (1) full-strength formula (FSF)/noninfected; (2) FSF/rotavirus infected; (3) half-strength formula (HSF)/noninfected; or (4) HSF/rotavirus infected. After one day of adjustment to the feeding rates, pigs were infected with rotavirus and acute effects on growth and diarrhea were monitored for 3 d and jejunal samples were collected for Ussing-chamber analyses. RESULTS: Piglets that were malnourished or infected had lower body weights on days 2 and 3 post-infection (P < 0.05). Three days post-infection, marked diarrhea and weight loss were accompanied by sharp reductions in villus height (59%) and lactase activity (91%) and increased crypt depth (21%) in infected compared with non-infected pigs (P < 0.05). Malnutrition also increased crypt depth (21%) compared to full-fed piglets. Villus:crypt ratio was reduced (67%) with viral infection. There was a trend for reduction in transepithelial electrical resistance with rotavirus infection and malnutrition (P = 0.1). 3H-mannitol flux was significantly increased (50%; P < 0.001) in rotavirus-infected piglets compared to non-infected piglets, but there was no effect of nutritional status. Furthermore, rotavirus infection reduced localization of the tight junction protein, occludin, in the cell membrane and increased localization in the cytosol. CONCLUSION: Overall, malnutrition had no additive effects to rotavirus infection on intestinal barrier function at day 3 post-infection in a neonatal piglet model. PMID:23964143

  14. Intestinal and Blood-Brain Barrier Permeability of Ginkgolides and Bilobalide: In Vitro and In Vivo Approaches

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In this study intestinal and blood brain barrier (BBB) transport of ginkgolides A, B, C, J and bilobalide, isolated from Ginkgo biloba (Family-Ginkgoaceae), was evaluated in Caco-2 and MDR1-MDCK cell monolayer models. Transepithelial transport was examined for 2 hours in both absorptive and secretor...

  15. Potential of Lactobacillus plantarum CCFM639 in Protecting against Aluminum Toxicity Mediated by Intestinal Barrier Function and Oxidative Stress

    PubMed Central

    Yu, Leilei; Zhai, Qixiao; Tian, Fengwei; Liu, Xiaoming; Wang, Gang; Zhao, Jianxin; Zhang, Hao; Narbad, Arjan; Chen, Wei

    2016-01-01

    Aluminum (Al) is a ubiquitous metal that can seriously harm the health of animals and humans. In our previous study, we demonstrated that Lactobacillus plantarum CCFM639 can decrease Al burden in the tissues of mice by inhibiting intestinal Al absorption. The main aim of the present research was to investigate whether the protection by the strain is also associated with enhancement of the intestinal barrier, alleviation of oxidative stress and modulation of the inflammatory response. In an in vitro cell model, two protection modes (intervention and therapy) were examined and the results indicated that L. plantarum CCFM639 alleviated Al-induced cytotoxicity. In a mouse model, L. plantarum CCFM639 treatment was found to significantly alleviate oxidative stress in the intestinal tract, regulate the function of the intestinal mucosal immune system, restore the integrity of tight junction proteins and maintain intestinal permeability. These results suggest that in addition to Al sequestration, L. plantarum CCFM639 can also inhibit Al absorption by protecting the intestinal barrier, alleviating Al-induced oxidative stress and inflammatory response. Therefore, L. plantarum CCFM639 has the potential to be a dietary supplement ingredient that provides protection against Al-induced gut injury. PMID:27918411

  16. Potential of Lactobacillus plantarum CCFM639 in Protecting against Aluminum Toxicity Mediated by Intestinal Barrier Function and Oxidative Stress.

    PubMed

    Yu, Leilei; Zhai, Qixiao; Tian, Fengwei; Liu, Xiaoming; Wang, Gang; Zhao, Jianxin; Zhang, Hao; Narbad, Arjan; Chen, Wei

    2016-12-02

    Aluminum (Al) is a ubiquitous metal that can seriously harm the health of animals and humans. In our previous study, we demonstrated that Lactobacillus plantarum CCFM639 can decrease Al burden in the tissues of mice by inhibiting intestinal Al absorption. The main aim of the present research was to investigate whether the protection by the strain is also associated with enhancement of the intestinal barrier, alleviation of oxidative stress and modulation of the inflammatory response. In an in vitro cell model, two protection modes (intervention and therapy) were examined and the results indicated that L. plantarum CCFM639 alleviated Al-induced cytotoxicity. In a mouse model, L. plantarum CCFM639 treatment was found to significantly alleviate oxidative stress in the intestinal tract, regulate the function of the intestinal mucosal immune system, restore the integrity of tight junction proteins and maintain intestinal permeability. These results suggest that in addition to Al sequestration, L. plantarum CCFM639 can also inhibit Al absorption by protecting the intestinal barrier, alleviating Al-induced oxidative stress and inflammatory response. Therefore, L. plantarum CCFM639 has the potential to be a dietary supplement ingredient that provides protection against Al-induced gut injury.

  17. Supplementation with L-glutamine prevents tumor growth and cancer-induced cachexia as well as restores cell proliferation of intestinal mucosa of Walker-256 tumor-bearing rats.

    PubMed

    Martins, Heber Amilcar; Sehaber, Camila Caviquioli; Hermes-Uliana, Catchia; Mariani, Fernando Augusto; Guarnier, Flavia Alessandra; Vicentini, Geraldo Emílio; Bossolani, Gleison Daion Piovezana; Jussani, Laraine Almeida; Lima, Mariana Machado; Bazotte, Roberto Barbosa; Zanoni, Jacqueline Nelisis

    2016-12-01

    This study aimed to evaluate the intestinal mucosa of the duodenum and jejunum of Walker-256 tumor-bearing rats supplemented with L-glutamine. Thirty-two male 50-day-old Wistar rats (Rattus norvegicus) were randomly divided into four groups: control (C), control supplemented with 2 % L-glutamine (GC), Walker-256 tumor (WT), and Walker-256 tumor supplemented with 2 % L-glutamine (TWG). Walker-256 tumor was induced by inoculation viable tumor cells in the right rear flank. After 10 days, celiotomy was performed and duodenal and jejunal tissues were removed and processed. We evaluated the cachexia index, proliferation index, villus height, crypt depth, total height of the intestinal wall, and number of goblet cells by the technique of periodic acid-Schiff (PAS). Induction of Walker-256 tumor promoted a reduction of metaphase index in the TW group animals, which was accompanied by a reduction in the villous height and crypt depths, resulting in atrophy of the intestinal wall as well as increased PAS-positive goblet cells. Supplementation with L-glutamine reduced the tumor growth and inhibited the development of the cachectic syndrome in animals of the TWG group. Furthermore, amino acid supplementation promoted beneficial effects on the intestinal mucosa in the TWG animals through restoration of the number of PAS-positive goblet cells. Therefore, supplementation with 2 % L-glutamine exhibited a promising role in the prevention of tumor growth and cancer-associated cachexia as well as restoring the intestinal mucosa in the duodenum and jejunum of Walker-256 tumor-bearing rats.

  18. Metabolism of cyadox by the intestinal mucosa microsomes and gut flora of swine, and identification of metabolites by high-performance liquid chromatography combined with ion trap/time-of-flight mass spectrometry.

    PubMed

    Xu, Ning; Huang, Lingli; Liu, Zhenli; Pan, Yuanhu; Wang, Xu; Tao, Yanfei; Chen, Dongmei; Wang, Yulian; Peng, Dapeng; Yuan, Zong hui

    2011-08-30

    Cyadox (CYX), 2-formylquinoxaline-1,4-dioxide cyanoacetylhydrazone, is an antimicrobial and growth-promoting feed additive for food-producing animals. To reveal biotransformation of CYX in swine intestine, CYX was incubated with swine intestinal microsomes and mucosa in the presence of an NADPH-generating system and swine ileal flora and colonic flora, respectively. The metabolites of CYX were identified using high-performance liquid chromatography combined with ion trap/time-of-flight mass spectrometry (LC/MS-ITTOF). Structural elucidation of the metabolites was precisely performed by comparing their changes in molecular mass, full scan MS/MS spectra and accurate mass measurements with those of the parent drug. Finally, seven metabolites were identified as follows: three reduced metabolites (cyadox 1-monoxide (Cy1), cyadox 4-monoxide (Cy2) and bisdesoxycyadox (Cy4)); hydroxylation metabolite (3-hydroxylcyadox 1-monoxide (Cy3)); hydrolysis metabolite of the amide bond (N-decyanoacetyl cyadox (Cy5)); a hydrogenation metabolite (11,12-dihydro-bisdesoxycyadox (Cy6)) and a side-chain cleavage metabolite (2-hydromethylquinoxaline (Cy7)). Only one metabolite (Cy1) was found in intestinal microsomes. Cy1, Cy2 and Cy4 were detected in intestinal mucosa, ileal and colonic flora. In addition, Cy3 and Cy5 were only obtained from ileal flora, and Cy6 and Cy7 alone were observed in colonic bacteria. The results indicated that N→O group reduction was the main metabolic pathway of CYX metabolism in swine ileal flora, intestinal microsomes and mucosa. New metabolic profiles of hydrogenation and cleavage on the side chain were found in colonic bacteria. Among the identified metabolites, two new metabolites (Cy6, Cy7) were detected for the first time. These studies will contribute to clarify comprehensively the metabolism of CYX in animals, and provide evidence to explain the pharmacology and toxicology effects of CYX in animals.

  19. Epithelium-intrinsic NAIP/NLRC4 inflammasome drives infected enterocyte expulsion to restrict Salmonella replication in the intestinal mucosa.

    PubMed

    Sellin, Mikael E; Müller, Anna A; Felmy, Boas; Dolowschiak, Tamas; Diard, Médéric; Tardivel, Aubry; Maslowski, Kendle M; Hardt, Wolf-Dietrich

    2014-08-13

    The gut mucosal epithelium separates the host from the microbiota, but enteropathogens such as Salmonella Typhimurium (S.Tm) can invade and breach this barrier. Defenses against such acute insults remain incompletely understood. Using a murine model of Salmonella enterocolitis, we analyzed mechanisms limiting pathogen loads in the epithelium during early infection. Although the epithelium-invading S.Tm replicate initially, this intraepithelial replicative niche is restricted by expulsion of infected enterocytes into the lumen. This mechanism is compromised if inflammasome components (NAIP1-6, NLRC4, caspase-1/-11) are deleted, or ablated specifically in the epithelium, resulting in ∼100-fold higher intraepithelial loads and accelerated lymph node colonization. Interestingly, the cytokines downstream of inflammasome activation, interleukin (IL)-1α/β and IL-18, appear dispensable for epithelial restriction of early infection. These data establish the role of an epithelium-intrinsic inflammasome, which drives expulsion of infected cells to restrict the pathogen's intraepithelial proliferation. This may represent a general defense mechanism against mucosal infections.

  20. Cellular uptake and transcytosis of lipid-based nanoparticles across the intestinal barrier: Relevance for oral drug delivery.

    PubMed

    Neves, Ana Rute; Queiroz, Joana Fontes; Costa Lima, Sofia A; Figueiredo, Francisco; Fernandes, Rui; Reis, Salette

    2016-02-01

    Oral administration is the preferred route for drug delivery and nanosystems represent a promising tool for protection and transport of hardly soluble, chemically unstable and poorly permeable drugs through the intestinal barrier. In the present work, we have studied lipid nanoparticles cellular uptake, internalization pathways and transcytosis routes through Caco-2 cell monolayers. Both lipid nanosystems presented similar size (∼180nm) and surface charge (-30mV). Nanostructured lipid carriers showed a higher cellular uptake and permeability across the barrier, but solid lipid nanoparticles could enter cells faster than the former. The internalization of lipid nanoparticles occurs mainly through a clathrin-mediated endocytosis mechanism, although caveolae-mediated endocytosis is also involved in the uptake. Both lipid nanoparticles were able to cross the intestinal barrier by a preferential transcellular route. This work contributed to a better knowledge of the developed nanosystems for the oral delivery of a wide spectrum of drugs.

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

    PubMed

    Segawa, Shuichi; Fujiya, Mikihiro; Konishi, Hiroaki; Ueno, Nobuhiro; Kobayashi, Naoyuki; Shigyo, Tatsuro; Kohgo, Yutaka

    2011-01-01

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

  2. Probiotic-Derived Polyphosphate Enhances the Epithelial Barrier Function and Maintains Intestinal Homeostasis through Integrin–p38 MAPK Pathway

    PubMed Central

    Segawa, Shuichi; Fujiya, Mikihiro; Konishi, Hiroaki; Ueno, Nobuhiro; Kobayashi, Naoyuki; Shigyo, Tatsuro; Kohgo, Yutaka

    2011-01-01

    Probiotics exhibit beneficial effects on human health, particularly in the maintenance of intestinal homeostasis in a complex manner notwithstanding the diversity of an intestinal flora between individuals. Thus, it is highly probable that some common molecules secreted by probiotic and/or commensal bacteria contribute to the maintenance of intestinal homeostasis and protect the intestinal epithelium from injurious stimuli. To address this question, we aimed to isolate the cytoprotective compound from a lactobacillus strain, Lactobacillus brevis SBC8803 which possess the ability to induce cytoprotective heat shock proteins in mouse small intestine. L. brevis was incubated in MRS broth and the supernatant was passed through with a 0.2-µm filter. Caco2/bbe cells were treated with the culture supernatant, and HSP27 expression was evaluated by Western blotting. HSP27-inducible components were separated by ammonium sulfate precipitation, DEAE anion exchange chromatography, gel filtration, and HPLC. Finally, we identified that the HSP27-inducible fraction was polyphosphate (poly P), a simple repeated structure of phosphates, which is a common product of lactobacilli and other bacteria associated with intestinal microflora without any definitive physiological functions. Then, poly P was synthesized by poly P-synthesizing enzyme polyphosphate kinase. The synthesized poly P significantly induced HSP27 from Caco2/BBE cells. In addition, Poly P suppressed the oxidant-induced intestinal permeability in the mouse small intestine and pharmacological inhibitors of p38 MAPK and integrins counteract its protective effect. Daily intrarectal administration of poly P (10 µg) improved the inflammation grade and survival rate in 4% sodium dextran sulfate-administered mice. This study, for the first time, demonstrated that poly P is the molecule responsible for maintaining intestinal barrier actions which are mediated through the intestinal integrin β1-p38 MAPK. PMID:21858054

  3. Characterization of mucosa-associated bacterial communities of the mouse intestine by terminal restriction fragment length polymorphism: Utility of sampling strategies and methods to reduce single-stranded DNA artifacts.

    PubMed

    Costa, Estela; Puhl, Nathan J; Selinger, L Brent; Inglis, G Douglas

    2009-08-01

    Terminal restriction fragment length polymorphism (T-RFLP) is a molecular technique used for comparative analysis of microbial community structure and dynamics. We evaluated three sampling methods for recovering bacterial community DNA associated with intestinal mucosa of mice (i.e. mechanical agitation with PBS, hand washing with PBS containing Tween 80, and direct DNA extraction from mucosal plugs). In addition, the utility of two methods (i.e. Klenow fragment and mung-bean nuclease) to reduce single-stranded DNA artifacts was tested. T-RFLP analysis indicated that diverse communities of bacteria are associated with mucosa of the ileum, cecum, and descending colon of mice. Although there was no significant difference in bacterial community structure between the mechanical agitation and direct DNA extraction methods regardless of intestinal location, community diversity was reduced for the hand wash method in the colon. The use of Klenow fragment and mung-bean nuclease have been reported to eliminate single-stranded DNA artifacts (i.e. pseudo-T-restriction fragments), but neither method was beneficial for characterizing mucosa-associated bacterial communities of the mouse cecum. Our study showed that the mechanical agitation and direct plug extraction methods yielded equivalent bacterial community DNA from the mucosa of the small and large intestines of mice, but the latter method was superior for logistical reasons. We also applied a combination of different statistical approaches to analyze T-RFLP data, including statistical detection of true peaks, analysis of variance for peak number, and group significance test, which provided a quantitative improvement for the interpretation of the T-RFLP data.

  4. Basic and clinical research on the regulation of the intestinal barrier by Lactobacillus and its active protein components: a review with experience of one center.

    PubMed

    Liu, Zhi-Hua; Kang, Liang; Wang, Jian-Ping

    2014-12-01

    Probiotics got protective effects on the intestinal barrier. Our present study is to review the basic and clinical progress on the regulation of the intestinal barrier by Lactobacillus and its active protein components, combing the study of our center. Our study have isolated the active component of micro integral membrane protein (MIMP) within the media place of the integral membrane protein of Lactobacillus plantarum, which was verified about the protective effects against the intestinal epithelial dysfunction. On the other hand, we also found the effects of perioperative use of probiotics in the prevention and treatment of postoperative intestinal barrier dysfunction, and reduction of the postoperative infective complications. In this review, we would like to report the founding of our center, involving in the basic and clinical research progress of regulation of intestinal barrier by Lactobacillus and its active protein component MIMP. Furthermore, we may also promote our following studies about the MIMP and its clinical verification.

  5. Protective Capacity of Resveratrol, a Natural Polyphenolic Compound, against Deoxynivalenol-Induced Intestinal Barrier Dysfunction and Bacterial Translocation.

    PubMed

    Ling, Ka-Ho; Wan, Murphy Lam Yim; El-Nezami, Hani; Wang, Mingfu

    2016-05-16

    Contamination of food/feedstuffs by mycotoxins is a serious problem worldwide, causing severe economic losses and serious health problems in animals/humans. Deoxynivalenol (DON) is a major mycotoxin contaminant and is known to impair intestinal barrier function. Grapes and red wine are rich in polyphenols, such as resveratrol (RES), which has striking antioxidant and anti-inflammatory activities. RES is a food-derived component; therefore, it may be simultaneously present with DON in the gastrointestinal tract. The aim of this study was to explore in vitro protective effects of RES against DON-induced intestinal damage. The results showed that RES could protect DON-induced bacteria translocation because of enhanced of intestinal barrier function by restoring the DON-induced decrease in transepithelial electrical resistance and increase in paracellular permeability. Further mechanistic studies demonstrated that RES protects against DON-induced barrier dysfunction by promoting the assembly of claudin-4 in the tight junction complex. This is probably mediated through modulation of IL-6 and IL-8 secretion via mitogen-activated protein kinase-dependent pathways. Our results imply that RES can protect against DON-induced intestinal damage and that RES may be used as a novel dietary intervention strategy to reduce DON toxicity in animals/humans.

  6. Modulation of the intestinal environment, innate immune response, and barrier function by dietary threonine and purified fiber during a coccidiosis challenge in broiler chicks.

    PubMed

    Wils-Plotz, E L; Jenkins, M C; Dilger, R N

    2013-03-01

    Coccidiosis is a major contributor to economic losses in the poultry industry due to its detrimental effects on growth performance and nutrient utilization. We hypothesized that the combined effects of supplemental dietary Thr and purified fiber may modulate the intestinal environment and positively affect intestinal immune responses and barrier function in broiler chicks infected with Eimeria maxima. A Thr-deficient basal diet (3.1 g of Thr/kg of diet) was supplemented with 70 g/kg of silica sand (control) or high-methoxy pectin and 1 of 2 concentrations of Thr (1.8 or 5.3 g/kg of diet; 4 diets total), and fed to chicks from hatch to d 16 posthatch. On d 10 posthatch, chicks received 0.5 mL of distilled water or an acute dose of Eimeria maxima (1.5 × 10(3) sporulated oocytes) with 6 replicate pens of 6 chicks per each of 8 treatment combinations (4 diets and 2 inoculation states). Body weight gain, feed intake, and G:F increased (P < 0.01) with addition of 5.3 g of Thr/kg of diet. Eimeria maxima schizonts were present only in intestinal tissue sampled from infected birds (P < 0.01). Weights of cecal digesta were highest (P < 0.01) in pectin-fed birds, and ceca with the heaviest weights also had the highest concentrations of total short-chain fatty acids. Expression of interleukin-12 in ileal mucosa was highest (P < 0.01) in infected birds receiving the control diet with 5.3 g of supplemental Thr/kg. In cecal tonsils, interferon-γ expression was highest in infected birds receiving the control diet (fiber × infection, P < 0.05); interferon-γ expression was lowest in infected birds fed the high Thr diet (Thr × infection, P < 0.05). There were no differences due to infection or Thr supplementation for cytokine expression in birds fed pectin-containing treatments. Overall, we conclude that although pectin has some protective function against coccidiosis, Thr supplementation had the greatest effect on intestinal immune response and maintenance of near normal growth

  7. Effects of continuous renal replacement therapy on intestinal mucosal barrier function during extracorporeal membrane oxygenation in a porcine model

    PubMed Central

    2014-01-01

    Backgrounds Extracorporeal membrane oxygenation (ECMO) has been recommended for treatment of acute, potentially reversible, life-threatening respiratory failure unresponsive to conventional therapy. Intestinal mucosal barrier dysfunction is one of the most critical pathophysiological disorders during ECMO. This study aimed to determine whether combination with CRRT could alleviate damage of intestinal mucosal barrier function during VV ECMO in a porcine model. Methods Twenty-four piglets were randomly divided into control(C), sham(S), ECMO(E) and ECMO + CRRT(EC) group. The animals were treated with ECMO or ECMO + CRRT for 24 hours. After the experiments, piglets were sacrificed. Jejunum, ileum and colon were harvested for morphologic examination of mucosal injury and ultrastructural distortion. Histological scoring was assessed according to Chiu’s scoring standard. Blood samples were taken from the animals at -1, 2, 6, 12 and 24 h during experiment. Blood, liver, spleen, kidney and mesenteric lymphnode were collected for bacterial culture. Serum concentrations of diamine oxidase (DAO) and intestinal fatty acid binding protein (I-FABP) were tested as markers to assess intestinal epithelial function and permeability. DAO levels were determined by spectrophotometry and I-FABP levels by enzyme linked immunosorbent assay. Results Microscopy findings showed that ECMO-induced intestinal microvillus shedding and edema, morphological distortion of tight junction between intestinal mucous epithelium and loose cell-cell junctions were significantly improved with combination of CRRT. No significance was detected on positive rate of serum bacterial culture. The elevated colonies of bacterial culture in liver and mesenteric lymphnode in E group reduced significantly in EC group (p < 0.05). Compared with E group, EC group showed significantly decreased level of serum DAO and I-FABP (p < 0.05). Conclusions CRRT can alleviate the intestinal mucosal dysfunction

  8. Ghrelin ameliorates intestinal barrier dysfunction in experimental colitis by inhibiting the activation of nuclear factor-kappa B

    SciTech Connect

    Cheng, Jian; Zhang, Lin; Dai, Weiqi; Mao, Yuqing; Li, Sainan; Wang, Jingjie; Li, Huanqing; Guo, Chuanyong; Fan, Xiaoming

    2015-02-27

    Aim: This study aimed to investigate the effect and underlying mechanism of ghrelin on intestinal barrier dysfunction in dextran sulfate sodium (DSS)-induced colitis. Methods and results: Acute colitis was induced in C57BL/6J mice by administering 2.5% DSS. Saline or 25, 125, 250 μg/kg ghrelin was administrated intraperitoneally (IP) to mice 1 day before colitis induction and on days 4, 5, and 6 after DSS administration. IP injection of a ghrelin receptor antagonist, [D-lys{sup 3}]-GHRP-6, was performed immediately prior to ghrelin injection. Ghrelin (125 or 250 μg/kg) could reduce the disease activity index, histological score, and myeloperoxidase activities in experimental colitis, and also prevented shortening of the colon. Ghrelin could prevent the reduction of transepithelial electrical resistance and tight junction expression, and bolstered tight junction structural integrity and regulated cytokine secretion. Ultimately, ghrelin inhibited nuclear factor kappa B (NF-κB), inhibitory κB-α, myosin light chain kinase, and phosphorylated myosin light chain 2 activation. Conclusions: Ghrelin prevented the breakdown of intestinal barrier function in DSS-induced colitis. The protective effects of ghrelin on intestinal barrier function were mediated by its receptor GHSR-1a. The inhibition of NF-κB activation might be part of the mechanism underlying the effects of ghrelin that protect against barrier dysfunction. - Highlights: • Ghrelin ameliorates intestinal barrier dysfunction in experimental colitis. • The effect of ghrelin is mediated by GHSR-1a. • Inhibition of NF-κB activation.

  9. Maternal exposure to carbamazepine at environmental concentrations can cross intestinal and placental barriers.

    PubMed

    Kaushik, Gaurav; Huber, David P; Aho, Ken; Finney, Bruce; Bearden, Shawn; Zarbalis, Konstantinos S; Thomas, Michael A

    2016-05-27

    Psychoactive pharmaceuticals have been found as teratogens at clinical dosage during pregnancy. These pharmaceuticals have also been detected in minute (ppb) concentrations in drinking water in the US, and are environmental contaminants that may be complicit in triggering neurological disorders in genetically susceptible individuals. Previous studies have determined that psychoactive pharmaceuticals (fluoxetine, venlafaxine and carbamazepine) at environmentally relevant concentrations enriched sets of genes regulating development and function of the nervous system in fathead minnows. Altered gene sets were also associated with potential neurological disorders, including autism spectrum disorders (ASD). Subsequent in vitro studies indicated that psychoactive pharmaceuticals altered ASD-associated synaptic protein expression and gene expression in human neuronal cells. However, it is unknown if environmentally relevant concentrations of these pharmaceuticals are able to cross biological barriers from mother to fetus, thus potentially posing risks to nervous system development. The main objective of this study was to test whether psychoactive pharmaceuticals (fluoxetine, venlafaxine, and carbamazepine) administered through the drinking water at environmental concentrations to pregnant mice could reach the brain of the developing embryo by crossing intestinal and placental barriers. We addressed this question by adding (2)H-isotope labeled pharmaceuticals to the drinking water of female mice for 20 days (10 pre-and 10 post-conception days), and quantifying (2)H-isotope enrichment signals in the dam liver and brain of developing embryos using isotope ratio mass spectrometry. Significant levels of (2)H enrichment was detected in the brain of embryos and livers of carbamazepine-treated mice but not in those of control dams, or for fluoxetine or venlafaxine application. These results provide the first evidence that carbamazepine in drinking water and at typical

  10. Relationship between expression of triggering receptor-1 on myeloid cells in intestinal tissue and intestinal barrier dysfunction in severe acute pancreatitis

    PubMed Central

    Yin, Kai; Dang, Sheng-chun; Zhang, Jian-xin

    2011-01-01

    BACKGROUND: Triggering receptor expressed on myeloid cells-1 (TREM-1) in the intestine was upregulated and correlated with disease activity in inflammatory bowel diseases. Membrane-bound TREM-1 protein is increased in the pancreas, liver and kidneys of patients with severe acute pancreatitis (SAP), suggesting that TREM-1 may act as an important mediator of inflammation and subsequent extra-pancreatic organ injury. This study aimed to investigate the relationship between the expression of TREM-1 in intestinal tissue and intestinal barrier dysfunction in SAP. METHODS: Sixty-four male Wistar rats were randomly divided into a sham operation group (SO group, n=32) and a SAP group (n=32). A SAP model was established by retrograde injection of 5% sodium deoxycholate into the bile-pancreatic duct. Specimens were taken from blood and intestinal tissue 2, 6, 12, and 48 hours after operation respectively. The levels of D-lactate, diamine oxidase (DAO) and endotoxin in serum were measured using an improved spectro-photometric method. The expression levels of TREM-1, interleukin-1β (IL-1β), and tumor necrosis factor-α (TNF-α) mRNA in terminal ileum were detected by real-time reverse transcription-polymerase chain reaction (RT-PCR). Specimens of the distal ileum were taken to determine pathological changes by a validated histology score. RESULTS: The serum levels of D-lactate, DAO and endotoxin were significantly increased in each subgroup of SAP compared with the SO group (P<0.01, P<0.05). The expression levels of TREM-1, IL-1β and TNF-α mRNA in the terminal ileum in each subgroup of SAP were significantly higher than those in the SO group (P<0.01, P<0.05). The expression level of TREM-1mRNA was positively correlated with IL-1β and TNF-α mRNA (r=0.956, P=0.044; r=0.986, P=0.015), but the correlation was not found between IL-1β mRNA and TNF-α mRNA (P=0.133). Compared to the SO group, the pathological changes were aggravated significantly in the SAP group. CONCLUSIONS

  11. Severity of pancreatitis-associated intestinal mucosal barrier injury is reduced following treatment with the NADPH oxidase inhibitor apocynin

    PubMed Central

    Deng, Wenhong; Abliz, Ablikim; Xu, Sheng; Sun, Rongze; Guo, Wenyi; Shi, Qiao; Yu, Jia; Wang, Weixing

    2016-01-01

    intestinal barrier dysfunction in sodium taurocholate-induced SAP, presumably via its role in the prevention of reactive oxygen species generation and inhibition of p38 MAPK and NF-κB pathway activation. These findings provide novel insight suggesting that pharmacological inhibition of NOX by apocynin may be considered a novel therapeutic method for the treatment of intestinal injury in SAP. PMID:27573037

  12. Matrix metalloproteinase 13 modulates intestinal epithelial barrier integrity in inflammatory diseases by activating TNF

    PubMed Central

    Vandenbroucke, Roosmarijn E; Dejonckheere, Eline; Van Hauwermeiren, Filip; Lodens, Sofie; De Rycke, Riet; Van Wonterghem, Elien; Staes, An; Gevaert, Kris; López-Otin, Carlos; Libert, Claude

    2013-01-01

    Several pathological processes, such as sepsis and inflammatory bowel disease (IBD), are associated with impairment of intestinal epithelial barrier. Here, we investigated the role of matrix metalloproteinase MMP13 in these diseases. We observed that MMP13−/− mice display a strong protection in LPS- and caecal ligation and puncture-induced sepsis. We could attribute this protection to reduced LPS-induced goblet cell depletion, endoplasmic reticulum stress, permeability and tight junction destabilization in the gut of MMP13−/− mice compared to MMP13+/+ mice. Both in vitro and in vivo, we found that MMP13 is able to cleave pro-TNF into bioactive TNF. By LC-MS/MS, we identified three MMP13 cleavage sites, which proves that MMP13 is an alternative TNF sheddase next to the TNF converting enzyme TACE. Similarly, we found that the same mechanism was responsible for the observed protection of the MMP13−/− mice in a mouse model of DSS-induced colitis. We identified MMP13 as an important mediator in sepsis and IBD via the shedding of TNF. Hence, we propose MMP13 as a novel drug target for diseases in which damage to the gut is essential. PMID:23723167

  13. Macleaya cordata Extract Decreased Diarrhea Score and Enhanced Intestinal Barrier Function in Growing Piglets

    PubMed Central

    Fang, Jun; Martínez, Yordan; Bin, Peng; Duraipandiyan, Veeramuthu; Yin, Yulong

    2016-01-01

    Macleaya cordata extract is of great scientific and practical interest to researchers, due to its antimicrobial and anti-inflammatory responses within experimental animals. This study was designed to determine the diarrhea score and innate immunity of growing piglets after they had received Macleaya cordata extract supplements. A total of 240 growing pigs were randomly assigned to one of three dietary treatments, with 8 replicates per treatment and 10 piglets per replicate. All pigs received a basal diet containing similar amounts of nutrients. The three treatments were a control (no additive), an antibiotic (200 mg/kg colistin), and the Macleaya cordata extract supplement group (40 mg/kg Macleaya cordata extract). The diarrhea score was calculated after D 28. The jejunal samples were obtained from five piglets selected randomly from each treatment on D 28. In comparison with the control group, the dietary Macleaya cordata extract and colistin group demonstrated a substantially decreased diarrhea score. The introduction of Macleaya cordata extract supplements to the diet significantly increased volumes of ZO-1 and claudin-1, particularly in comparison with the pigs in the control group (P < 0.05). The findings indicate that Macleaya cordata extract does enhance intestinal barrier function in growing piglets and that it could be used as a viable substitute for antibiotics. PMID:27525260

  14. New advances in the pathophysiology of intestinal ion transport and barrier function in diarrhea and the impact on therapy.

    PubMed

    Hoque, Kazi Mirajul; Chakraborty, Subhra; Sheikh, Irshad Ali; Woodward, Owen M

    2012-06-01

    Diarrhea remains a continuous threat to human health worldwide. Scaling up the best practices for diarrhea prevention requires improved therapies. Diarrhea results from dysregulation of normal intestinal ion transport functions. Host-microbe contact is a key determinant of this response. Underlying mechanisms in the disease state are regulated by intracellular signals that modulate the activity of individual transport proteins responsible for ion transport and barrier function. Similarly, virulence factors of pathogens and their complex interaction with the host has shed light on the mechanism of enteric infection. Great advances in our understanding of the pathophysiologic mechanisms of epithelial transport, and host-microbe interaction have been made in recent years. Application of these new advances may represent strategies to decrease pathogen attachment, enhance intestinal cation absorption, decrease anion secretion and repair barrier function. This review highlights the new advances and better understanding in the pathophysiology of diarrheal diseases and their impact on therapy.

  15. Protective Effects of Ferulic Acid against Heat Stress-Induced Intestinal Epithelial Barrier Dysfunction In Vitro and In Vivo.

    PubMed

    He, Shasha; Liu, Fenghua; Xu, Lei; Yin, Peng; Li, Deyin; Mei, Chen; Jiang, Linshu; Ma, Yunfei; Xu, Jianqin

    2016-01-01

    Heat stress is important in the pathogenesis of intestinal epithelial barrier dysfunction. Ferulic acid (FA), a phenolic acid widely found in fruits and vegetables, can scavenge free radicals and activate cell stress responses. This study is aimed at investigating protective effects of FA on heat stress-induced dysfunction of the intestinal epithelial barrier in vitro and in vivo. Intestinal epithelial (IEC-6) cells were pretreated with FA for 4 h and then exposed to heat stress. Heat stress caused decreased transepithelial electrical resistance (TER) and increased permeability to 4-kDa fluorescein isothiocyanate (FITC)-dextran (FD4). Both effects were inhibited by FA in a dose-dependent manner. FA significantly attenuated the decrease in occludin, ZO-1 and E-cadherin expression observed with heat stress. The distortion and redistribution of occludin, ZO-1 and E-cadherin proteins were also effectively prevented by FA pretreatment. Moreover, heat stress diminished electron-dense material detected in tight junctions (TJs), an effect also alleviated by FA in a dose-dependent manner. In an in vivo heat stress model, FA (50 mg/kg) was administered to male Sprague-Dawley rats for 7 consecutive days prior to exposure to heat stress. FA pretreatment significantly attenuated the effects of heat stress on the small intestine, including the increased FD4 permeability, disrupted tight junctions and microvilli structure, and reduced occludin, ZO-1 and E-cadherin expression. Taken together, our results demonstrate that FA pretreatment is potentially protective against heat stress-induced intestinal epithelial barrier dysfunction.

  16. Effect of Fusarium-Derived Metabolites on the Barrier Integrity of Differentiated Intestinal Porcine Epithelial Cells (IPEC-J2)

    PubMed Central

    Springler, Alexandra; Vrubel, Galina-Jacqueline; Mayer, Elisabeth; Schatzmayr, Gerd; Novak, Barbara

    2016-01-01

    The human, animal and plant pathogen Fusarium, which contaminates agricultural commodities worldwide, produces numerous secondary metabolites. An example is the thoroughly-investigated deoxynivalenol (DON), which severely impairs gastrointestinal barrier integrity. However, to date, the toxicological profile of other Fusarium-derived metabolites, such as enniatins, beauvericin, moniliformin, apicidin, aurofusarin, rubrofusarin, equisetin and bikaverin, are poorly characterized. Thus we examined their effects—as metabolites alone and as metabolites in combination with DON—on the intestinal barrier function of differentiated intestinal porcine epithelial cells (IPEC-J2) over 72 h. Transepithelial electrical resistance (TEER) was measured at 24-h intervals, followed by evaluation of cell viability using neutral red (NR) assay. Enniatins A, A1, B and B1, apicidin, aurofusarin and beauvericin significantly reduced TEER. Moniliformin, equisetin, bikaverin and rubrofusarin had no effect on TEER. In the case of apicidin, aurofusarin and beauvericin, TEER reductions were further substantiated by the addition of otherwise no-effect DON concentrations. In all cases, viability was unaffected, confirming that TEER reductions were not due to compromised viability. Considering the prevalence of mycotoxin contamination and the diseases associated with intestinal barrier disruption, consumption of contaminated food or feed may have substantial health implications. PMID:27869761

  17. Effects of Lactobacillus johnsonii and Lactobacillus reuteri on gut barrier function and heat shock proteins in intestinal porcine epithelial cells

    PubMed Central

    Liu, Hao-Yu; Roos, Stefan; Jonsson, Hans; Ahl, David; Dicksved, Johan; Lindberg, Jan Erik; Lundh, Torbjörn

    2015-01-01

    Heat shock proteins (HSPs) are a set of highly conserved proteins that can serve as intestinal gate keepers in gut homeostasis. Here, effects of a probiotic, Lactobacillus rhamnosus GG (LGG), and two novel porcine isolates, Lactobacillus johnsonii strain P47-HY and Lactobacillus reuteri strain P43-HUV, on cytoprotective HSP expression and gut barrier function, were investigated in a porcine IPEC-J2 intestinal epithelial cell line model. The IPEC-J2 cells polarized on a permeable filter exhibited villus-like cell phenotype with development of apical microvilli. Western blot analysis detected HSP expression in IPEC-J2 and revealed that L. johnsonii and L. reuteri strains were able to significantly induce HSP27, despite high basal expression in IPEC-J2, whereas LGG did not. For HSP72, only the supernatant of L. reuteri induced the expression, which was comparable to the heat shock treatment, which indicated that HSP72 expression was more stimulus specific. The protective effect of lactobacilli was further studied in IPEC-J2 under an enterotoxigenic Escherichia coli (ETEC) challenge. ETEC caused intestinal barrier destruction, as reflected by loss of cell–cell contact, reduced IPEC-J2 cell viability and transepithelial electrical resistance, and disruption of tight junction protein zonula occludens-1. In contrast, the L. reuteri treatment substantially counteracted these detrimental effects and preserved the barrier function. L. johnsonii and LGG also achieved barrier protection, partly by directly inhibiting ETEC attachment. Together, the results indicate that specific strains of Lactobacillus can enhance gut barrier function through cytoprotective HSP induction and fortify the cell protection against ETEC challenge through tight junction protein modulation and direct interaction with pathogens. PMID:25847917

  18. Diosmectite-zinc oxide composite improves intestinal barrier restoration and modulates TGF-β1, ERK1/2, and Akt in piglets after acetic acid challenge.

    PubMed

    Song, Z-H; Ke, Y-L; Xiao, K; Jiao, L-F; Hong, Q-H; Hu, C-H

    2015-04-01

    The present study evaluated the beneficial effect of diosmectite-zinc oxide composite (DS-ZnO) on improving intestinal barrier restoration in piglets after acetic acid challenge and explored the underlying mechanisms. Twenty-four 35-d-old piglets (Duroc × Landrace × Yorkshire), with an average weight of 8.1 kg, were allocated to 4 treatment groups. On d 1 of the trial, colitis was induced via intrarectal injection of acetic acid (10 mL of 10% acetic acid [ACA] solution for ACA, DS-ZnO, and mixture of diosmectite [DS] and ZnO [DS+ZnO] groups) and the control group was infused with saline. Twenty-four hours after challenged, piglets were fed with the following diets: 1) control group (basal diet), 2) ACA group (basal diet), 3) DS-ZnO group (basal diet supplemented with DS-ZnO), and 4) DS+ZnO group (mixture of 1.5 g diosmectite [DS]/kg and 500 mg Zn/kg from ZnO [equal amount of DS and ZnO in the DS-ZnO treatment group]). On d 8 of the trial, piglets were sacrificed. The results showed that DS-ZnO supplementation improved (P < 0.05) ADG, ADFI, and transepithelial electrical resistance and decreased (P < 0.05) fecal scores, crypt depth, and fluorescein isothiocyanate-dextran 4 kDa (FD4) influx as compared with ACA group. Moreover, DS-ZnO increased (P < 0.05) occludin, claudin-1, and zonula occluden-1 expressions; reduced (P < 0.05) caspase-9 and caspase-3 activity and Bax expression; and improved (P < 0.05) Bcl2, XIAP, and PCNA expression. Diosmectite-zinc oxide composite supplementation also increased (P < 0.05) TGF-β1 expression and ERK1/2 and Akt activation. These results suggest that DS-ZnO attenuates the acetic acid-induced colitis by improving mucosa barrier restoration, inhibiting apoptosis, and improving intestinal epithelial cells proliferation and modulation of TGF-β1 and ERK1/2 and Akt signaling pathway.

  19. Butyrate enhances the intestinal barrier by facilitating tight junction assembly via activation of AMP-activated protein kinase in Caco-2 cell monolayers.

    PubMed

    Peng, Luying; Li, Zhong-Rong; Green, Robert S; Holzman, Ian R; Lin, Jing

    2009-09-01

    Butyrate, one of the SCFA, promotes the development of the intestinal barrier. However, the molecular mechanisms underlying the butyrate regulation of the intestinal barrier are unknown. To test the hypothesis that the effect of butyrate on the intestinal barrier is mediated by the regulation of the assembly of tight junctions involving the activation of the AMP-activated protein kinase (AMPK), we determined the effect of butyrate on the intestinal barrier by measuring the transepithelial electrical resistance (TER) and inulin permeability in a Caco-2 cell monolayer model. We further used a calcium switch assay to study the assembly of epithelial tight junctions and determined the effect of butyrate on the assembly of epithelial tight junctions and AMPK activity. We demonstrated that the butyrate treatment increased AMPK activity and accelerated the assembly of tight junctions as shown by the reorganization of tight junction proteins, as well as the development of TER. AMPK activity was also upregulated by butyrate during calcium switch-induced tight junction assembly. Compound C, a specific AMPK inhibitor, inhibited the butyrate-induced activation of AMPK. The facilitating effect of butyrate on the increases in TER in standard culture media, as well as after calcium switch, was abolished by compound C. We conclude that butyrate enhances the intestinal barrier by regulating the assembly of tight junctions. This dynamic process is mediated by the activation of AMPK. These results suggest an intriguing link between SCFA and the intracellular energy sensor for the development of the intestinal barrier.

  20. Effect of a probiotic mixture on intestinal microflora, morphology, and barrier integrity of broilers subjected to heat stress.

    PubMed

    Song, J; Xiao, K; Ke, Y L; Jiao, L F; Hu, C H; Diao, Q Y; Shi, B; Zou, X T

    2014-03-01

    The current study investigated the efficacy of a probiotic mixture on ameliorating heat stress-induced impairment of intestinal microflora, morphology, and barrier integrity in broilers. The probiotic mixture contained Bacillus licheniformis, Bacillus subtilis, and Lactobacillus plantarum. Three hundred sixty 21-d-old Ross 308 male broilers were allocated in 4 experimental treatments, each of which was replicated 6 times with 15 broilers per replicate. A 2 × 2 factorial design was used in the study, and the main factors were composed of diet (basal diet or addition of 1.5 g/kg of probiotic mixture) and temperature (thermoneutral zone or heat stress). From d 22 to 42, birds were either raised in a thermoneutral zone (22°C) or subjected to cyclic heat stress by exposing them to 33°C for 10 h (from 0800 to 1800) and 22°C from 1800 to 0800. Compared with birds kept in the thermoneutral zone, birds subjected to heat stress had reduced ADG and ADFI; lower viable counts of Lactobacillus and Bifidobacterium and increased viable counts of coliforms and Clostridium in small intestinal contents; shorter jejunal villus height, deeper crypt depth, and lower ratio of villus height to crypt depth; decreased jejunal transepithelial electrical resistance and a higher level of jejunal paracellular permeability of fluorescein isothiocyanate dextran 4 kDa; and downregulated protein levels of occludin and zonula occludens-1 (P < 0.05). Supplemental probiotics increased (P < 0.05) small intestinal Lactobacillus and Bifidobacterium, jejunal villus height, protein level of occludin, and decreased (P < 0.05) feed to gain ratio and small intestinal coliforms. These results indicate that dietary addition of probiotic mixture was effective in partially ameliorating intestinal barrier function. But no temperature × diet interaction was observed in the present study, revealing that the supplemented probiotics had the same effect at both temperatures.

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

    PubMed

    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.

  2. Are There Any Different Effects of Bifidobacterium, Lactobacillus and Streptococcus on Intestinal Sensation, Barrier Function and Intestinal Immunity in PI-IBS Mouse Model?

    PubMed Central

    Wang, Huan; Gong, Jing; Wang, Wenfeng; Long, Yanqin; Fu, Xiaochao; Fu, Yu; Qian, Wei; Hou, Xiaohua

    2014-01-01

    Background and Aims Research has increasingly suggested that gut flora plays an important role in the development of post-infectious irritable bowel syndrome (PI-IBS). Studies of the curative effect of probiotics for IBS have usually been positive but not always. However, the differences of treatment effects and mechanisms among probiotic stains, or mixture of them, are not clear. In this study, we compared the effects of different probiotics (Befidobacterium, Lactobacillus, Streptococcus or mixture of the three) on intestinal sensation, barrier function and intestinal immunity in PI-IBS mouse model. Methods PI-IBS model was induced by Trichinella spiralis infection in mice. Different probiotics were administered to mice after 8 weeks infection. Visceral sensitivity was measured by scores of abdominal withdrawal reflex (AWR) and the threshold intensity of colorectal distention. Colonic smooth muscle contractile response was assessed by contraction of the longitudinal muscle strips. Plasma diamine oxidase (DAO) and d-lactate were determined by an enzymatic spectrophotometry. Expression of tight junction proteins and cytokines in ileum were measured by Western blotting. Results Compared to control mice, PI-IBS mice treated either alone with Befidobacterium or Lactobacillus (but not Streptococcus), or the mixture of the three exhibited not only decreased AWR score and contractile response, but also reduced plasma DAO and D-lactate. These probiotic treatments also suppressed the expression of proinflammatory cytokine IL-6 and IL-17 and promoted the expression of major tight junction proteins claudin-1 and occludin. The mixture of the three probiotic strains performed better than the individual in up-regulating these tight junction proteins and suppressing IL-17 expression. Conclusions Bifidobacterium and Lactobacillus, but not Streptococcus, alleviated visceral hypersensitivity and recovered intestinal barrier function as well as inflammation in PI-IBS mouse model

  3. Persistence and Toxin Production by Clostridium difficile within Human Intestinal Organoids Result in Disruption of Epithelial Paracellular Barrier Function

    PubMed Central

    Leslie, Jhansi L.; Huang, Sha; Opp, Judith S.; Nagy, Melinda S.; Kobayashi, Masayuki; Young, Vincent B.

    2014-01-01

    Clostridium difficile is the leading cause of infectious nosocomial diarrhea. The pathogenesis of C. difficile infection (CDI) results from the interactions between the pathogen, intestinal epithelium, host immune system, and gastrointestinal microbiota. Previous studies of the host-pathogen interaction in CDI have utilized either simple cell monolayers or in vivo models. While much has been learned by utilizing these approaches, little is known about the direct interaction of the bacterium with a complex host epithelium. Here, we asked if human intestinal organoids (HIOs), which are derived from pluripotent stem cells and demonstrate small intestinal morphology and physiology, could be used to study the pathogenesis of the obligate anaerobe C. difficile. Vegetative C. difficile, microinjected into the lumen of HIOs, persisted in a viable state for up to 12 h. Upon colonization with C. difficile VPI 10463, the HIO epithelium is markedly disrupted, resulting in the loss of paracellular barrier function. Since similar effects were not observed when HIOs were colonized with the nontoxigenic C. difficile strain F200, we directly tested the role of toxin using TcdA and TcdB purified from VPI 10463. We show that the injection of TcdA replicates the disruption of the epithelial barrier function and structure observed in HIOs colonized with viable C. difficile. PMID:25312952

  4. Persistence and toxin production by Clostridium difficile within human intestinal organoids result in disruption of epithelial paracellular barrier function.

    PubMed

    Leslie, Jhansi L; Huang, Sha; Opp, Judith S; Nagy, Melinda S; Kobayashi, Masayuki; Young, Vincent B; Spence, Jason R

    2015-01-01

    Clostridium difficile is the leading cause of infectious nosocomial diarrhea. The pathogenesis of C. difficile infection (CDI) results from the interactions between the pathogen, intestinal epithelium, host immune system, and gastrointestinal microbiota. Previous studies of the host-pathogen interaction in CDI have utilized either simple cell monolayers or in vivo models. While much has been learned by utilizing these approaches, little is known about the direct interaction of the bacterium with a complex host epithelium. Here, we asked if human intestinal organoids (HIOs), which are derived from pluripotent stem cells and demonstrate small intestinal morphology and physiology, could be used to study the pathogenesis of the obligate anaerobe C. difficile. Vegetative C. difficile, microinjected into the lumen of HIOs, persisted in a viable state for up to 12 h. Upon colonization with C. difficile VPI 10463, the HIO epithelium is markedly disrupted, resulting in the loss of paracellular barrier function. Since similar effects were not observed when HIOs were colonized with the nontoxigenic C. difficile strain F200, we directly tested the role of toxin using TcdA and TcdB purified from VPI 10463. We show that the injection of TcdA replicates the disruption of the epithelial barrier function and structure observed in HIOs colonized with viable C. difficile.

  5. Baicalein induces CD4+Foxp3+ T cells and enhances intestinal barrier function in a mouse model of food allergy

    PubMed Central

    Bae, Min-Jung; Shin, Hee Soon; See, Hye-Jeong; Jung, Sun Young; Kwon, Da-Ae; Shon, Dong-Hwa

    2016-01-01

    The incidence of food allergy, which is triggered by allergen permeation of the gastrointestinal tract followed by a T-helper (Th) 2-mediated immune response, has been increasing annually worldwide. We examined the effects of baicalein (5,6,7-trihydroxyflavone), a flavonoid from Scutellaria baicalensis used in oriental herbal medicine, on regulatory T (Treg) cell induction and intestinal barrier function through the regulation of tight junctions in a mouse model of food allergy. An allergic response was induced by oral challenge with ovalbumin, and the incidence of allergic symptoms and T cell-related activity in the mesenteric lymph nodes were analyzed with and without the presence of baicalein. Our results demonstrated that the administration of baicalein ameliorated the symptoms of food allergy and attenuated serum IgE and effector T cells. However, Treg-related factors were up-regulated by baicalein. Furthermore, baicalein was shown to enhance intestinal barrier function through the regulation of tight junctions. We also found that baicalein treatment induced the differentiation of Treg cells via aryl hydrocarbon receptors (AhRs). Thus, the action of baicalein as an agonist of AhR can induce Treg differentiation and enhance barrier function, suggesting that baicalein might serve as an effective immune regulator derived from foods for the treatment of food allergy. PMID:27561877

  6. The role of the intestinal microvasculature in inflammatory bowel disease: studies with a modified Caco-2 model including endothelial cells resembling the intestinal barrier in vitro

    PubMed Central

    Kasper, Jennifer Y; Hermanns, Maria Iris; Cavelius, Christian; Kraegeloh, Annette; Jung, Thomas; Danzebrink, Rolf; Unger, Ronald E; Kirkpatrick, Charles James

    2016-01-01

    The microvascular endothelium of the gut barrier plays a crucial role during inflammation in inflammatory bowel disease. We have modified a commonly used intestinal cell model based on the Caco-2 cells by adding microvascular endothelial cells (ISO-HAS-1). Transwell filters were used with intestinal barrier-forming Caco-2 cells on top and the ISO-HAS-1 on the bottom of the filter. The goal was to determine whether this coculture mimics the in vivo situation more closely, and whether the model is suitable to evaluate interactions of, for example, prospective nanosized drug vehicles or contrast agents with this coculture in a physiological and inflamed state as it would occur in inflammatory bowel disease. We monitored the inflammatory responsiveness of the cells (release of IL-8, soluble intercellular adhesion molecule 1, and soluble E-selectin) after exposure to inflammatory stimuli (lipopolysaccharide, TNF-α, INF-γ, IL1-β) and a nanoparticle (Ba/Gd: coprecipitated BaSO4 and Gd(OH)3), generally used as contrast agents. The barrier integrity of the coculture was evaluated via the determination of transepithelial electrical resistance and the apparent permeability coefficient (Papp) of NaFITC. The behavior of the coculture Caco-1/ISO-HAS-1 was compared to the respective monocultures Caco-2 and ISO-HAS-1. Based on transepithelial electrical resistance, the epithelial barrier integrity of the coculture remained stable during incubation with all stimuli, whereas the Papp decreased after exposure to the cytokine mixture (TNF-α, INF-γ, IL1-β, and Ba/Gd). Both the endothelial and epithelial monocultures showed a high inflammatory response in both the upper and lower transwell-compartments. However, in the coculture, inflammatory mediators were only detected on the epithelial side and not on the endothelial side. Thus in the coculture, based on the Papp, the epithelial barrier appears to prevent a potential inflammatory overreaction in the underlying endothelial cells

  7. The role of the intestinal microvasculature in inflammatory bowel disease: studies with a modified Caco-2 model including endothelial cells resembling the intestinal barrier in vitro.

    PubMed

    Kasper, Jennifer Y; Hermanns, Maria Iris; Cavelius, Christian; Kraegeloh, Annette; Jung, Thomas; Danzebrink, Rolf; Unger, Ronald E; Kirkpatrick, Charles James

    The microvascular endothelium of the gut barrier plays a crucial role during inflammation in inflammatory bowel disease. We have modified a commonly used intestinal cell model based on the Caco-2 cells by adding microvascular endothelial cells (ISO-HAS-1). Transwell filters were used with intestinal barrier-forming Caco-2 cells on top and the ISO-HAS-1 on the bottom of the filter. The goal was to determine whether this coculture mimics the in vivo situation more closely, and whether the model is suitable to evaluate interactions of, for example, prospective nanosized drug vehicles or contrast agents with this coculture in a physiological and inflamed state as it would occur in inflammatory bowel disease. We monitored the inflammatory responsiveness of the cells (release of IL-8, soluble intercellular adhesion molecule 1, and soluble E-selectin) after exposure to inflammatory stimuli (lipopolysaccharide, TNF-α, INF-γ, IL1-β) and a nanoparticle (Ba/Gd: coprecipitated BaSO4 and Gd(OH)3), generally used as contrast agents. The barrier integrity of the coculture was evaluated via the determination of transepithelial electrical resistance and the apparent permeability coefficient (Papp) of NaFITC. The behavior of the coculture Caco-1/ISO-HAS-1 was compared to the respective monocultures Caco-2 and ISO-HAS-1. Based on transepithelial electrical resistance, the epithelial barrier integrity of the coculture remained stable during incubation with all stimuli, whereas the Papp decreased after exposure to the cytokine mixture (TNF-α, INF-γ, IL1-β, and Ba/Gd). Both the endothelial and epithelial monocultures showed a high inflammatory response in both the upper and lower transwell-compartments. However, in the coculture, inflammatory mediators were only detected on the epithelial side and not on the endothelial side. Thus in the coculture, based on the Papp, the epithelial barrier appears to prevent a potential inflammatory overreaction in the underlying endothelial cells

  8. Clinical Characteristics Associated with Post-Operative Intestinal Epithelial Barrier Dysfunction in Children with Congenital Heart Disease

    PubMed Central

    Typpo, Katri V; Larmonier, Claire B.; Deschenes, Jendar; Redford, Daniel; Kiela, Pawel R.; Ghishan, Fayez K.

    2014-01-01

    Objective Children with congenital heart disease (CHD) have loss of intestinal epithelial barrier function (EBF), which increases their risk for post-operative sepsis and organ dysfunction. We do not understand how post-operative cardiopulmonary support or the inflammatory response to cardiopulmonary bypass (CPB) might alter intestinal EBF. We examined variation in a panel of plasma biomarkers to reflect intestinal EBF (cellular and paracellular structure and function) after CPB and in response to routine ICU care. Design Prospective cohort Setting University medical center cardiac intensive care unit Patients Twenty children aged newborn to 18 years undergoing repair or palliation of CHD with CPB. Interventions We measured baseline and repeated plasma FABP2, citrulline, claudin 3, and dual sugar permeability test (DSPT) to reflect intestinal epithelial integrity, epithelial function, paracellular integrity, and paracellular function, respectively. We measured baseline and repeated plasma pro-inflammatory (IL-6, TNF-α, IFN-γ) and anti-inflammatory (IL4, IL10) cytokines, known to modulate intestinal EBF in murine models of CPB. Measurements and Main Results All patients had abnormal baseline FABP2 concentrations (mean 3815.5 pg/mL), (normal 41–336 pg/mL). Cytokine response to CPB was associated with early, but not late changes in plasma concentrations of FABP2 and citrulline. Variation in biomarker concentrations over time were associated with aspects of ICU care indicating greater severity of illness: claudin 3, FABP2, and DSPT ratio were associated with symptoms of feeding intolerance (p<0.05) while FABP2 was positively associated with vasoactive-inotrope score (VIS) (p=0.04). Citrulline was associated with larger arteriovenous O2 saturation difference (p=0.04) and had a complex relationship with VIS. Conclusions Children undergoing CPB for repair or palliation of CHD are at risk for intestinal injury and often present with evidence for loss of intestinal

  9. Altered intestinal microbial flora and impaired epithelial barrier structure and function in CKD: the nature, mechanisms, consequences and potential treatment.

    PubMed

    Vaziri, Nosratola D; Zhao, Ying-Yong; Pahl, Madeleine V

    2016-05-01

    Chronic kidney disease (CKD) results in systemic inflammation and oxidative stress which play a central role in CKD progression and its adverse consequences. Although many of the causes and consequences of oxidative stress and inflammation in CKD have been extensively explored, little attention had been paid to the intestine and its microbial flora as a potential source of these problems. Our recent studies have revealed significant disruption of the colonic, ileal, jejunal and gastric epithelial tight junction in different models of CKD in rats. Moreover, the disruption of the epithelial barrier structure and function found in uremic animals was replicated in cultured human colonocytes exposed to uremic human plasma in vitro We have further found significant changes in the composition and function of colonic bacterial flora in humans and animals with advanced CKD. Together, uremia-induced impairment of the intestinal epithelial barrier structure and function and changes in composition of the gut microbiome contribute to the systemic inflammation and uremic toxicity by accommodating the translocation of endotoxin, microbial fragments and other noxious luminal products in the circulation. In addition, colonic bacteria are the main source of several well-known pro-inflammatory uremic toxins such as indoxyl sulfate, p-cresol sulfate, trimethylamine-N-oxide and many as-yet unidentified retained compounds in end-stage renal disease patients. This review is intended to provide an overview of the effects of CKD on the gut microbiome and intestinal epithelial barrier structure and their role in the pathogenesis of systemic inflammation and uremic toxicity. In addition, potential interventions aimed at mitigating these abnormalities are briefly discussed.

  10. Optimal dietary protein level improved growth, disease resistance, intestinal immune and physical barrier function of young grass carp (Ctenopharyngodon idella).

    PubMed

    Xu, Jing; Wu, Pei; Jiang, Wei-Dan; Liu, Yang; Jiang, Jun; Kuang, Sheng-Yao; Tang, Ling; Tang, Wu-Neng; Zhang, Yong-An; Zhou, Xiao-Qiu; Feng, Lin

    2016-08-01

    This study investigated the effects of dietary proteins on the growth, disease resistance, intestinal immune and physical barrier functions of young grass carp (Ctenopharyngodon idella). A total of 540 young grass carp (264.11 ± 0.76 g) were fed six diets containing graded levels of protein (143.1, 176.7, 217.2, 257.5, 292.2 and 322.8 g digestible protein kg(-1) diet) for 8 weeks. After the growth trial, fish were challenged with Aeromonas hydrophila and mortalities were recorded for 14 days. The results indicated that optimal dietary protein levels: increased the production of antibacterial components, up-regulated anti-inflammatory cytokines, inhibitor of κBα, target of rapamycin and ribosomal protein S6 kinases 1 mRNA levels, whereas down-regulated pro-inflammatory cytokines, nuclear factor kappa B (NF-κB) P65, NF-κB P52, c-Rel, IκB kinase β, IκB kinase γ and eIF4E-binding proteins 2 mRNA levels in three intestinal segments of young grass carp (P < 0.05), suggesting that optimal dietary protein level could enhance fish intestinal immune barrier function; up-regulated the mRNA levels of tight junction complexes, B-cell lymphoma protein-2, inhibitor of apoptosis proteins, myeloid cell leukemia-1 and NF-E2-related factor 2, and increased the activities and mRNA levels of antioxidant enzymes, whereas down-regulated myosin light chain kinase, cysteinyl aspartic acid-protease 2, 3, 7, 8, 9, fatty acid synthetase ligand, apoptotic protease activating factor-1, Bcl-2 associated X protein, p38 mitogen-activated protein kinase, c-Jun N-terminal protein kinase and Kelch-like-ECH-associated protein 1b mRNA levels, and decreased reactive oxygen species, malondialdehyde and protein carbonyl contents in three intestinal segments of young grass carp (P < 0.05), indicating that optimal dietary protein level could improve fish intestinal physical barrier function. Finally, the optimal dietary protein levels for the growth performance (PWG) and against enteritis

  11. Effect of Lactobacillus plantarum on diarrhea and intestinal barrier function of young piglets challenged with enterotoxigenic Escherichia coli K88.

    PubMed

    Yang, K M; Jiang, Z Y; Zheng, C T; Wang, L; Yang, X F

    2014-04-01

    The present study was performed to investigate the preventative effect of Lactobacillus plantarum on diarrhea in relation to intestinal barrier function in young piglets challenged with enterotoxigenic Escherichia coli (ETEC) K88. Seventy-two male piglets (4 d old) were assigned to 2 diets (antibiotic-free basal diet with or without L. plantarum, 5 × 10(10) cfu/kg diet) and subsequently challenged or not with ETEC K88 (1 × 10(8) cfu per pig) on d 15 in a 2 × 2 factorial arrangement of treatments. Feed intake and BW were measured on d 15 and 18 (3 d after challenge) for determination of growth performance. On d 18, 1 piglet from each pen was slaughtered to evaluate small intestinal morphology and expression of tight junction proteins at the mRNA and protein levels while another piglet was used for the intestinal permeability test. Before and after ETEC K88 challenge, piglets fed L. plantarum had greater BW, ADG, and ADFI (P < 0.05) and marginally greater G:F (P < 0.10) compared to piglets fed the unsupplemented diet. After ETEC K88 challenge, the challenged piglets did not show an impaired growth performance but had greater incidence of diarrhea compared to the nonchallenged piglets. There was an interaction between dietary L. plantarum and ETEC K88 challenge (P < 0.05) as L. plantarum prevented the ETEC K88-induced diarrhea. Piglets challenged with ETEC K88 also had greater urinary lactulose:mannitol and plasma concentration of endotoxin, shorter villi, deeper crypt depth, and reduced villous height:crypt depth in the duodenum and jejunum and decreased zonula occludens-1 mRNA and occludin mRNA and protein expression in the jejunum (P < 0.05). These deleterious effects caused by ETEC K88 were inhibited by feeding L. plantarum (P < 0.05). There were no effects of either treatment on the morphology and expression of tight junction proteins in ileum. In conclusion, L. plantarum, given to piglets in early life, improved performance and effectively prevented the

  12. Protective effects of Lactobacillus plantarum on epithelial barrier disruption caused by enterotoxigenic Escherichia coli in intestinal porcine epithelial cells.

    PubMed

    Wu, Yunpeng; Zhu, Cui; Chen, Zhuang; Chen, Zhongjian; Zhang, Weina; Ma, Xianyong; Wang, Li; Yang, Xuefen; Jiang, Zongyong

    2016-04-01

    Tight junctions (TJs) play an important role in maintaining the mucosal barrier function and gastrointestinal health of animals. Lactobacillus plantarum (L. plantarum) was reported to protect the intestinal barrier function of early-weaned piglets against enterotoxigenic Escherichia coli (ETEC) K88 challenge; however, the underlying cellular mechanism of this protection was unclear. Here, an established intestinal porcine epithelia cell (IPEC-J2) model was used to investigate the protective effects and related mechanisms of L. plantarum on epithelial barrier damages induced by ETEC K88. Epithelial permeability, expression of inflammatory cytokines, and abundance of TJ proteins, were determined. Pre-treatment with L. plantarum for 6h prevented the reduction in transepithelial electrical resistance (TEER) (P<0.05), inhibited the increased transcript abundances of interleukin-8 (IL-8) and tumor necrosis factor (TNF-α) (P<0.05), decreased expression of claudin-1, occludin and zonula occludens (ZO-1) (P<0.05) and protein expression of occludin (P<0.05) of IPEC-J2 cells caused by ETEC K88. Moreover, the mRNA expression of negative regulators of toll-like receptors (TLRs) [single Ig Il-1-related receptor (SIGIRR), B-cell CLL/lymphoma 3 (Bcl3), and mitogen-activated protein kinase phosphatase-1 (MKP-1)] in IPEC-J2 cells pre-treated with L. plantarum were higher (P<0.05) compared with those in cells just exposed to K88. Furthermore, L. plantarum was shown to regulate proteins of nuclear factor κB (NF-κB) and mitogen-activated protein kinase (MAPK) signaling pathways. These results indicated that L. plantarum may improve epithelial barrier function by maintenance of TEER, inhibiting the reduction of TJ proteins, and reducing the expression of proinflammatory cytokines induced by ETEC K88, possibly through modulation of TLRs, NF-κB and MAPK pathways.

  13. Collagen peptides ameliorate intestinal epithelial barrier dysfunction in immunostimulatory Caco-2 cell monolayers via enhancing tight junctions.

    PubMed

    Chen, Qianru; Chen, Oliver; Martins, Isabela M; Hou, Hu; Zhao, Xue; Blumberg, Jeffrey B; Li, Bafang

    2017-03-22

    Dysfunction of the intestinal barrier plays a key role in the pathogenesis of inflammatory bowel disease (IBD) and multiple organ failure. The effect of Alaska pollock skin-derived collagen and its 3 tryptic hydrolytic fractions, HCP (6 kDa retentate), MCP (3 kDa retentate) and LCP (3 kDa permeate) on TNF-α induced barrier dysfunction was investigated in Caco-2 cell monolayers. TNF-α induced barrier dysfunction was significantly attenuated by the collagen and its peptide fractions, especially LCP, compared to TNF-α treated controls (P < 0.05). Compared to a negative control, 24 h pre-incubation with 2 mg mL(-1) LCP significantly alleviated the TNF-α induced breakdown of the tight junction protein ZO-1 and occludin and inhibited MLC phosphorylation and MLCK expression. The activation of NFκB and Elk-1 was suppressed by LCP. Thus, collagen peptides may attenuate TNF-α induced barrier dysfunction of Caco-2 cells by inhibiting the NFκB and ERK1/2-mediated MLCK pathway with associated decreases in ZO-1 and occludin protein expression.

  14. Effects of Soybean Agglutinin on Mechanical Barrier Function and Tight Junction Protein Expression in Intestinal Epithelial Cells from Piglets

    PubMed Central

    Pan, Li; Qin, Guixin; Zhao, Yuan; Wang, Jun; Liu, Feifei; Che, Dongsheng

    2013-01-01

    In this study, we sought to investigate the role of soybean agglutinin (SBA) in mediating membrane permeability and the mechanical barrier function of intestinal epithelial cells. The IPEC-J2 cells were cultured and treated with 0, 0.5, 1.0, 1.5, 2.0, 2.5, or 3.0 mg/mL SBA. Transepithelial electrical resistance (TEER) and alkaline phosphatase (AP) activity were measured to evaluate membrane permeability. The results showed a significant decrease in TEER values (p < 0.05) in a time- and dose-dependent manner, and a pronounced increase in AP activity (p < 0.05). Cell growth and cell morphology were used to evaluate the cell viability. A significant cell growth inhibition (p < 0.05) and alteration of morphology were observed when the concentration of SBA was increased. The results of western blotting showed that the expression levels of occludin and claudin-3 were decreased by 31% and 64% compared to those of the control, respectively (p < 0.05). In addition, immunofluorescence labeling indicated an obvious decrease in staining of these targets and changes in their localizations. In conclusion, SBA increased the membrane permeability, inhibited the cell viability and reduced the levels of tight junction proteins (occludin and claudin-3), leading to a decrease in mechanical barrier function in intestinal epithelial cells. PMID:24189218

  15. Impaired Intestinal Mucosal Barrier upon Ischemia-Reperfusion: “Patching Holes in the Shield with a Simple Surgical Method”

    PubMed Central

    Rosero, Olivér; Ónody, Péter; Molnár, Dávid; Lotz, Gábor; Turóczi, Zsolt; Fülöp, András; Garbaisz, Dávid; Harsányi, László; Szijártó, Attila

    2014-01-01

    Mesenteric ischemia-reperfusion (IR) is associated with impairment of the gut barrier function and the initiation of a proinflammatory cascade with life-threatening results. Therefore methods directed to ameliorate IR injury are of great importance. We aimed at describing the effects of postconditioning (PC) on the alterations of the intestinal mucosal function and the inflammatory response upon mesenteric IR. Methods. Male Wistar rats were gavaged with green fluorescent protein-expressing E. coli suspensions. Animals were randomized into three groups (n = 15), sham-operated, IR-, and PC-groups, and underwent 60 minutes of superior mesenteric artery occlusion, followed by 6 hours of reperfusion. Postconditioning was performed at the onset of reperfusion. Blood and tissue samples were taken at the end of reperfusion, for histological, bacteriological, and plasma examinations. Results. The PC-group presented a more favorable claudin-2, claudin-3, claudin-4, and zonula occludens-1 membrane expression profile, and significantly lower rates of bacterial translocation to distant organs and plasma D-lactate levels compared to the IR-group. Histopathological lesions, plasma I-FABP, IL-6, and TNF-α levels were significantly lower in the PC-group compared to the IR-group. Conclusion. The use of postconditioning improved the integrity of the intestinal mucosal barrier upon mesenteric IR, and thus reduced the incidence of bacterial translocation and development of a systemic inflammatory response. PMID:24955347

  16. Effects of yeast products on the intestinal morphology, barrier function, cytokine expression, and antioxidant system of weaned piglets*

    PubMed Central

    Yang, Huan-sheng; Wu, Fei; Long, Li-na; Li, Tie-jun; Xiong, Xia; Liao, Peng; Liu, Hong-nan; Yin, Yu-long

    2016-01-01

    The goal of this study was to evaluate the effects of a mixture of yeast culture, cell wall hydrolysates, and yeast extracts (collectively “yeast products,” YP) on the performance, intestinal physiology, and health of weaned piglets. A total of 90 piglets weaned at 21 d of age were blocked by body weight, sex, and litter and randomly assigned to one of three treatments for a 14-d feeding experiment, including (1) a basal diet (control), (2) 1.2 g/kg of YP, and (3) 20 mg/kg of colistin sulfate (CSE). No statistically significant differences were observed in average daily feed intake, average daily weight gain, or gain-to-feed ratio among CSE, YP, and control piglets. Increased prevalence of diarrhea was observed among piglets fed the YP diet, whereas diarrhea was less prevalent among those fed CSE. Duodenal and jejunal villus height and duodenal crypt depth were greater in the control group than they were in the YP or CSE groups. Intraepithelial lymphocytes (IEL) in the duodenal and jejunal villi were enhanced by YP, whereas IEL in the ileal villi were reduced in weaned piglets fed YP. Secretion of jejunal and ileal interleukin-10 (IL-10) was higher and intestinal and serum antioxidant indexes were affected by YP and CSE. In YP- and CSE-supplemented animals, serum D-lactate concentration and diamine oxidase (DAO) activity were both increased, and intestinal mRNA expressions of occludin and ZO-1 were reduced as compared to the control animals. In conclusion, YP supplementation in the diets of weaned piglets appears to increase the incidence of diarrhea and has adverse effects on intestinal morphology and barrier function. PMID:27704745

  17. Effect of Vitamin E Supplementation on Intestinal Barrier Function in Rats Exposed to High Altitude Hypoxia Environment

    PubMed Central

    Sun, Rui; Qiao, Xiangjin; Xu, Cuicui; Shang, Xiaoya; Niu, Weining; Chao, Yu

    2014-01-01

    The study was conducted to investigate the role of vitamin E in the high altitude hypoxia-induced damage to the intestinal barrier in rats. Sprague-Dawley rats were divided into control (Control), high altitude hypoxia (HH), and high altitude hypoxia+vitamin E (250 mg/kg BW*d) (HV) groups. After the third day, the HH and HV groups were placed in a hypobaric chamber at a stimulated elevation of 7000 m for 5 days. The rats in the HV group were given vitamin E by gavage daily for 8 days. The other rats were given equal volume saline. The results showed that high altitude hypoxia caused the enlargement of heart, liver, lung and kidney, and intestinal villi damage. Supplementation with vitamin E significantly alleviated hypoxia-caused damage to the main organs including intestine, increased the serum superoxide dismutase (SOD) (p< 0.05), diamino oxidase (DAO) (p< 0.01) levels, and decreased the serum levels of interleukin-2 (IL-2) (p< 0.01), interleukin-4 (IL-4) (p<0.001), interferon-gamma (IFN-γ) (p<0.01) and malondialdehyde (MDA) (p<0.001), and decreased the serum erythropoietin (EPO) activity (p<0.05). Administration of vitamin E significantly increased the S-IgA (p<0.001) in ileum and significantly improved the expression levels of occludin and IκBα, and decreased the expression levels of hypoxia-inducible factor 1 alpha and 2 alpha (HIF-1α and HIF-2α), Toll-like receptors (TLR4), P-IκBα and nuclear factor-κB p65(NF-κB P65) in ileum compared to the HH group. This study suggested that vitamin E protectis from intestinal injury caused by high altitude hypoxia environment. These effects may be related to the HIF and TLR4/NF-κB signaling pathway. PMID:25177163

  18. Remediation of hemorrhagic shock-induced intestinal barrier dysfunction by treatment with diphenyldihaloketones EF24 and CLEFMA.

    PubMed

    Yadav, Vivek R; Hussain, Alamdar; Sahoo, Kaustuv; Awasthi, Vibhudutta

    2014-11-01

    Gut is very sensitive to hypoperfusion and hypoxia, and deranged gastrointestinal barrier is implicated in systemic failure of various organs. We recently demonstrated that diphenyldihaloketone EF24 [3,5-bis(2-fluorobenzylidene)piperidin-4-one] improves survival in a rat model of hemorrhagic shock. In this study, we tested EF24 and its other analog CLEFMA (4-[3,5-bis(2-chlorobenzylidene)-4-oxo-piperidine-1-yl]-4-oxo-2-butenoic acid) for their effect on intestinal barrier dysfunction in hypovolemic shock. Hypovolemia was induced in rats by withdrawing 50% of blood. EF24 or CLEFMA (0.4 mg/kg i.p.) treatment was provided, without volume resuscitation, after 1 hour of hemorrhage. Ileum was collected 5 hours after the treatment to investigate the expression of tight junction proteins (zonula occludens, claudin, and occludin) and epithelial injury markers [myeloperoxidase, ileal lipid-binding protein (ILBP), CD163, and plasma citrulline]. The ileal permeability for dextran-fluoroisothiocyanate and Evan's blue dye was determined. EF24 and CLEFMA reduced the hypovolemia-induced plasma citrulline levels and the ileal expression of myeloperoxidase, ILBP, and CD163. The drugs also restored the basal expression levels of zonula occludens, claudin, and occludin, which were substantially deranged by hypovolemia. In ischemic ileum, the expression of phospho(tyrosine)-zonula occludens-1 was reduced, which was reinstated by EF24 and CLEFMA. In contrast, the drug treatments maintained the hypovolemia-induced expression of phospho(threonine)-occludin, but reduced that of phospho(tyrosine)-occludin. Both EF24 and CLEFMA treatments reduced the intestinal permeability enhanced by hypovolemia. EF24 and CLEFMA attenuate hypovolemic gut pathology and protect barrier function by restoring the status of tight junction proteins. These effects were observed in unresuscitated shock, implying the benefit of EF24 and CLEFMA in prehospital care of shock.

  19. Alpha-Melanocyte Stimulating Hormone Protects against Cytokine-Induced Barrier Damage in Caco-2 Intestinal Epithelial Monolayers

    PubMed Central

    Váradi, Judit; Harazin, András; Fenyvesi, Ferenc; Réti-Nagy, Katalin; Gogolák, Péter; Vámosi, György; Bácskay, Ildikó; Fehér, Pálma; Ujhelyi, Zoltán; Vasvári, Gábor; Róka, Eszter; Haines, David; Deli, Mária A.; Vecsernyés, Miklós

    2017-01-01

    Alpha-melanocyte-stimulating hormone (α-MSH) is a potent anti-inflammatory peptide with cytoprotective effect in various tissues. The present investigation demonstrates the ability of α-MSH to interact with intestinal epithelial cell monolayers and mitigate inflammatory processes of the epithelial barrier. The protective effect of α-MSH was studied on Caco-2 human intestinal epithelial monolayers, which were disrupted by exposure to tumor necrosis factor-α and interleukin-1β. The barrier integrity was assessed by measuring transepithelial electric resistance (TEER) and permeability for marker molecules. Caco-2 monolayers were evaluated by immunohistochemistry for expression of melanocortin-1 receptor and tight junction proteins ZO-1 and claudin-4. The activation of nuclear factor kappa beta (NF-κB) was detected by fluorescence microscopy and inflammatory cytokine expression was assessed by flow cytometric bead array cytokine assay. Exposure of Caco-2 monolayers to proinflammatory cytokines lowered TEER and increased permeability for fluorescein and albumin, which was accompanied by changes in ZO-1 and claudin-4 immunostaining. α-MSH was able to prevent inflammation-associated decrease of TEER in a dose-dependent manner and reduce the increased permeability for paracellular marker fluorescein. Further immunohistochemistry analysis revealed proinflammatory cytokine induced translocation of the NF-κB p65 subunit into Caco-2 cell nuclei, which was inhibited by α-MSH. As a result the IL-6 and IL-8 production of Caco-2 monolayers were also decreased with different patterns by the addition of α-MSH to the culture medium. In conclusion, Caco-2 cells showed a positive immunostaining for melanocortin-1 receptor and α-MSH protected Caco-2 cells against inflammatory barrier dysfunction and inflammatory activation induced by tumor necrosis factor-α and interleukin-1β cytokines. PMID:28103316

  20. Geniposide ameliorates TNBS-induced experimental colitis in rats via reducing inflammatory cytokine release and restoring impaired intestinal barrier function.

    PubMed

    Xu, Bin; Li, Yan-Li; Xu, Ming; Yu, Chang-Chun; Lian, Meng-Qiao; Tang, Ze-Yao; Li, Chuan-Xun; Lin, Yuan

    2017-03-06

    Geniposide is an iridoid glycosides purified from the fruit of Gardenia jasminoides Ellis, which is known to have antiinflammatory, anti-oxidative and anti-tumor activities. The present study aimed to investigate the effects of geniposide on experimental rat colitis and to reveal the related mechanisms. Experimental rat colitis was induced by rectal administration of a TNBS solution. The rats were treated with geniposide (25, 50 mg·kg(-1)·d(-1), ig) or with sulfasalazine (SASP, 100 mg·kg(-1)·d(-1), ig) as positive control for 14 consecutive days. A Caco-2 cell monolayer exposed to lipopolysaccharides (LPS) was used as an epithelial barrier dysfunction model. Transepithelial electrical resistance (TER) was measured to evaluate intestinal barrier function. In rats with TNBS-induced colitis, administration of geniposide or SASP significantly increased the TNBS-decreased body weight and ameliorated TNBS-induced experimental colitis and related symptoms. Geniposide or SASP suppressed inflammatory cytokine (TNF-α, IL-1β, and IL-6) release and neutrophil infiltration (myeloperoxidase activity) in the colon. In Caco-2 cells, geniposide (25-100 μmol/L) ameliorated LPS-induced endothelial barrier dysfunction via dose-dependently increasing transepithelial electrical resistance (TER). The results from both in vivo and in vitro studies revealed that geniposide down-regulated NF-κB, COX-2, iNOS and MLCK protein expression, up-regulated the expression of tight junction proteins (occludin and ZO-1), and facilitated AMPK phosphorylation. Both AMPK siRNA transfection and AMPK overexpression abrogated the geniposide-reduced MLCK protein expression, suggesting that geniposide ameliorated barrier dysfunction via AMPK-mediated inhibition of the MLCK pathway. In conclusion, geniposide ameliorated TNBS-induced experimental rat colitis by both reducing inflammation and modulating the disrupted epithelial barrier function via activating the AMPK signaling pathway..

  1. Characterization of the Adherence of Clostridium difficile Spores: The Integrity of the Outermost Layer Affects Adherence Properties of Spores of the Epidemic Strain R20291 to Components of the Intestinal Mucosa

    PubMed Central

    Mora-Uribe, Paola; Miranda-Cárdenas, Camila; Castro-Córdova, Pablo; Gil, Fernando; Calderón, Iván; Fuentes, Juan A.; Rodas, Paula I.; Banawas, Saeed; Sarker, Mahfuzur R.; Paredes-Sabja, Daniel

    2016-01-01

    Clostridium difficile is the causative agent of the most frequently reported nosocomial diarrhea worldwide. The high incidence of recurrent infection is the main clinical challenge of C. difficile infections (CDI). Formation of C. difficile spores of the epidemic strain R20291 has been shown to be essential for recurrent infection and transmission of the disease in a mouse model. However, the underlying mechanisms of how these spores persist in the colonic environment remains unclear. In this work, we characterized the adherence properties of epidemic R20291 spores to components of the intestinal mucosa, and we assessed the role of the exosporium integrity in the adherence properties by using cdeC mutant spores with a defective exosporium layer. Our results showed that spores and vegetative cells of the epidemic R20291 strain adhered at high levels to monolayers of Caco-2 cells and mucin. Transmission electron micrographs of Caco-2 cells demonstrated that the hair-like projections on the surface of R20291 spores are in close proximity with the plasma membrane and microvilli of undifferentiated and differentiated monolayers of Caco-2 cells. Competitive-binding assay in differentiated Caco-2 cells suggests that spore-adherence is mediated by specific binding sites. By using spores of a cdeC mutant we demonstrated that the integrity of the exosporium layer determines the affinity of adherence of C. difficile spores to Caco-2 cells and mucin. Binding of fibronectin and vitronectin to the spore surface was concentration-dependent, and depending on the concentration, spore-adherence to Caco-2 cells was enhanced. In the presence of an aberrantly-assembled exosporium (cdeC spores), binding of fibronectin, but not vitronectin, was increased. Notably, independent of the exosporium integrity, only a fraction of the spores had fibronectin and vitronectin molecules binding to their surface. Collectively, these results demonstrate that the integrity of the exosporium layer of

  2. Characterization of the Adherence of Clostridium difficile Spores: The Integrity of the Outermost Layer Affects Adherence Properties of Spores of the Epidemic Strain R20291 to Components of the Intestinal Mucosa.

    PubMed

    Mora-Uribe, Paola; Miranda-Cárdenas, Camila; Castro-Córdova, Pablo; Gil, Fernando; Calderón, Iván; Fuentes, Juan A; Rodas, Paula I; Banawas, Saeed; Sarker, Mahfuzur R; Paredes-Sabja, Daniel

    2016-01-01

    Clostridium difficile is the causative agent of the most frequently reported nosocomial diarrhea worldwide. The high incidence of recurrent infection is the main clinical challenge of C. difficile infections (CDI). Formation of C. difficile spores of the epidemic strain R20291 has been shown to be essential for recurrent infection and transmission of the disease in a mouse model. However, the underlying mechanisms of how these spores persist in the colonic environment remains unclear. In this work, we characterized the adherence properties of epidemic R20291 spores to components of the intestinal mucosa, and we assessed the role of the exosporium integrity in the adherence properties by using cdeC mutant spores with a defective exosporium layer. Our results showed that spores and vegetative cells of the epidemic R20291 strain adhered at high levels to monolayers of Caco-2 cells and mucin. Transmission electron micrographs of Caco-2 cells demonstrated that the hair-like projections on the surface of R20291 spores are in close proximity with the plasma membrane and microvilli of undifferentiated and differentiated monolayers of Caco-2 cells. Competitive-binding assay in differentiated Caco-2 cells suggests that spore-adherence is mediated by specific binding sites. By using spores of a cdeC mutant we demonstrated that the integrity of the exosporium layer determines the affinity of adherence of C. difficile spores to Caco-2 cells and mucin. Binding of fibronectin and vitronectin to the spore surface was concentration-dependent, and depending on the concentration, spore-adherence to Caco-2 cells was enhanced. In the presence of an aberrantly-assembled exosporium (cdeC spores), binding of fibronectin, but not vitronectin, was increased. Notably, independent of the exosporium integrity, only a fraction of the spores had fibronectin and vitronectin molecules binding to their surface. Collectively, these results demonstrate that the integrity of the exosporium layer of

  3. Collagen accumulation and dysfunctional mucosal barrier of the small intestine in patients with chronic heart failure.

    PubMed

    Arutyunov, Gregory P; Kostyukevich, Olga I; Serov, Roman A; Rylova, Natalya V; Bylova, Nadezda A

    2008-04-10

    Chronic heart failure is a systemic disease with a devastating prognosis, which affects many organ systems other than the cardiovascular system. A total of 45 Chronic heart failure patients of ischemic etiology and 18 control subjects aged 45-65 years were recruited. All subjects underwent a physical examination by a qualified physician, echocardiography, an evaluation of the trophological status (including height and weight assessment) and net-of-fat body mass (NFBM) determination, an evaluation of intestinal functional activity based on fat and protein excretion with feces, and biopsy examination from the small intestine (see below). For all of them were performed functional tests of the small intestine and morphological examination of the small intestine and biopsy collection. Staining for collagen content of the mucosal wall showed that collagen content differed significantly between the four cohorts studied. In fact, relative collagen content was highest in advanced stages of the disease. However, patients with cardiac cachexia displayed even higher relative amounts of collagen than those of the same functional class without cardiac cachexia. Both fat loss and protein loss with the feces correlated with relative collagen area.

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

    DTIC Science & Technology

    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

  5. Intestinal barrier dysfunction develops at the onset of experimental autoimmune encephalomyelitis, and can be induced by adoptive transfer of auto-reactive T cells.

    PubMed

    Nouri, Mehrnaz; Bredberg, Anders; Weström, Björn; Lavasani, Shahram

    2014-01-01

    Multiple sclerosis (MS) is a chronic inflammatory demyelinating disease of the central nervous system with a pathogenesis involving a dysfunctional blood-brain barrier and myelin-specific, autoreactive T cells. Although the commensal microbiota seems to affect its pathogenesis, regulation of the interactions between luminal antigens and mucosal immune elements remains unclear. Herein, we investigated whether the intestinal mucosal barrier is also targeted in this disease. Experimental autoimmune encephalomyelitis (EAE), the prototypic animal model of MS, was induced either by active immunization or by adoptive transfer of autoreactive T cells isolated from these mice. We show increased intestinal permeability, overexpression of the tight junction protein zonulin and alterations in intestinal morphology (increased crypt depth and thickness of the submucosa and muscularis layers). These intestinal manifestations were seen at 7 days (i.e., preceding the onset of neurological symptoms) and at 14 days (i.e., at the stage of paralysis) after immunization. We also demonstrate an increased infiltration of proinflammatory Th1/Th17 cells and a reduced regulatory T cell number in the gut lamina propria, Peyer's patches and mesenteric lymph nodes. Adoptive transfer to healthy mice of encephalitogenic T cells, isolated from EAE-diseased animals, led to intestinal changes similar to those resulting from the immunization procedure. Our findings show that disruption of intestinal homeostasis is an early and immune-mediated event in EAE. We propose that this intestinal dysfunction may act to support disease progression, and thus represent a potential therapeutic target in MS. In particular, an increased understanding of the regulation of tight junctions at the blood-brain barrier and in the intestinal wall may be crucial for design of future innovative therapies.

  6. Urinary Trypsin Inhibitor Ameliorates Seawater Immersion-Induced Intestinal Mucosa Injury via Antioxidation, Modulation of NF-κB Activity, and Its Related Cytokines in Rats with Open Abdominal Injury

    PubMed Central

    Zhang, Xing Jian; Wang, Ya Li; Zhou, Song; Xue, Xiaojun; Liu, Qiang; Zhang, Wen Hua; Zheng, Jun

    2014-01-01

    Objective. To investigate the role of oxidative stress, NF-κB activity, and its related cytokines in the pathogenesis of seawater immersion after open abdominal injury (SI-OAI) and whether UTI treatment can attenuate SI-OAI induced IMI. Methods. Wistar rats were randomly divided into three groups: C group, S group, and U group. The rats in C group only suffered from anesthesia and surgical operation, whereas the rats in S group and U group received caudal vein injection of normal saline without/with 50,000 U/kg body weight of UTI. The activities of TNF-α, IL-6, SOD, MDA, ROS, NF-κB, and IκB-β were monitored by ELISA, biochemical methods, EMSA, and Western blot, respectively. Results. The plasma inflammatory mediators and the contents of MDA, ROS, and NF-κB in intestine as well as the pathological scores in ileal mucosa were significantly increased in rats after SI-OAI, accompanied by a reduction in SOD activities and IκB-β levels. UTI treatment significantly attenuated intestinal histopathological changes with evidence of a decrease in all of the parameters, except for upregulation of the levels of SOD and IκB-β protein. Conclusion. UTI can attenuate SI-OAI induced IMI via inhibition of NF-κB activity, subsequently inhibiting the expression of inflammatory cytokines and by combating oxidative stress. PMID:25210512

  7. Pasture v. standard dairy cream in high-fat diet-fed mice: improved metabolic outcomes and stronger intestinal barrier.

    PubMed

    Benoit, Bérengère; Plaisancié, Pascale; Géloën, Alain; Estienne, Monique; Debard, Cyrille; Meugnier, Emmanuelle; Loizon, Emmanuelle; Daira, Patricia; Bodennec, Jacques; Cousin, Olivier; Vidal, Hubert; Laugerette, Fabienne; Michalski, Marie-Caroline

    2014-08-28

    Dairy products derived from the milk of cows fed in pastures are characterised by higher amounts of conjugated linoleic acid and α-linolenic acid (ALA), and several studies have shown their ability to reduce cardiovascular risk. However, their specific metabolic effects compared with standard dairy in a high-fat diet (HFD) context remain largely unknown; this is what we determined in the present study with a focus on the metabolic and intestinal parameters. The experimental animals were fed for 12 weeks a HFD containing 20 % fat in the form of a pasture dairy cream (PDC) or a standard dairy cream (SDC). Samples of plasma, liver, white adipose tissue, duodenum, jejunum and colon were analysed. The PDC mice, despite a higher food intake, exhibited lower fat mass, plasma and hepatic TAG concentrations, and inflammation in the adipose tissue than the SDC mice. Furthermore, they exhibited a higher expression of hepatic PPARα mRNA and adipose tissue uncoupling protein 2 mRNA, suggesting an enhanced oxidative activity of the tissues. These results might be explained, in part, by the higher amounts of ALA in the PDC diet and in the liver and adipose tissue of the PDC mice. Moreover, the PDC diet was found to increase the proportions of two strategic cell populations involved in the protective function of the intestinal epithelium, namely Paneth and goblet cells in the small intestine and colon, compared with the SDC diet. In conclusion, a PDC HFD leads to improved metabolic outcomes and to a stronger gut barrier compared with a SDC HFD. This may be due, at least in part, to the protective mechanisms induced by specific lipids.

  8. The impact of lactoferrin with different levels of metal saturation on the intestinal epithelial barrier function and mucosal inflammation.

    PubMed

    Majka, Grzegorz; Więcek, Grażyna; Śróttek, Małgorzata; Śpiewak, Klaudyna; Brindell, Małgorzata; Koziel, Joanna; Marcinkiewicz, Janusz; Strus, Magdalena

    2016-12-01

    Translocation of bacteria, primarily Gram-negative pathogenic flora, from the intestinal lumen into the circulatory system leads to sepsis. In newborns, and especially very low birth weight infants, sepsis is a major cause of morbidity and mortality. The results of recently conducted clinical trials suggest that lactoferrin, an iron-binding protein that is abundant in mammalian colostrum and milk, may be an effective agent in preventing sepsis in newborns. However, despite numerous basic studies on lactoferrin, very little is known about how metal saturation of this protein affects a host's health. Therefore, the main objective of this study was to elucidate how iron-depleted, iron-saturated, and manganese-saturated forms of lactoferrin regulate intestinal barrier function via interactions with epithelial cells and macrophages. For these studies, a human intestinal epithelial cell line, Caco-2, was used. In this model, none of the tested lactoferrin forms induced higher levels of apoptosis or necrosis. There was also no change in the production of tight junction proteins regardless of lactoferrin metal saturation status. None of the tested forms induced a pro-inflammatory response in Caco-2 cells or in macrophages either. However, the various lactoferrin forms did effectively inhibit the pro-inflammatory response in macrophages that were activated with lipopolysaccharide with the most potent effect observed for apolactoferrin. Lactoferrin that was not bound to its cognate receptor was able to bind and neutralize lipopolysaccharide. Lactoferrin was also able to neutralize microbial-derived antigens, thereby potentially reducing their pro-inflammatory effect. Therefore, we hypothesize that lactoferrin supplementation is a relevant strategy for preventing sepsis.

  9. Weaning induces both transient and long-lasting modifications of absorptive, secretory, and barrier properties of piglet intestine.

    PubMed

    Boudry, Gaëlle; Péron, Vincent; Le Huërou-Luron, Isabelle; Lallès, Jean Paul; Sève, Bernard

    2004-09-01

    This study investigated intestinal physiology of piglets at weaning. Piglets (n = 60) weaned at 21 d were food deprived for 2 d and then tube-fed using 2 different diets (a conventional diet vs. a wheat-enriched diet). They were slaughtered at d 0, 2, 5, 8, or 15 postweaning. Jejunum, ileum, and colon were mounted in Ussing chambers. In addition, segments of the proximal jejunum of 4 growing pigs were studied 35 d after weaning. Secretory function was assessed by basal short-circuit current (Isc) and secretagogue-stimulated Isc. Glucose absorption was measured by the increase in Isc after the addition of glucose. Epithelial barrier function was measured by transmucosal resistance (R) and horseradish peroxidase (HRP) fluxes across the epithelium. There were no significant differences between the pigs fed the 2 diets for any of the parameters studied. As already reported, a transient villous atrophy was observed. At the same time, we observed an increased basal Isc in jejunum and colon, increased glucose absorption and a dramatic drop of R in jejunum. These parameters had returned to preweaning values by d 5. Weaning was also followed by long-lasting modifications. In jejunum, responses to the secretagogues and glucose absorption were decreased at wk 2 after weaning and were not different between d 15 and 35. Ileal transmucosal resistance increased on d 5 and was stable thereafter. HRP flux in jejunum declined on d 2 and stayed at this low level throughout the experiment. We conclude that weaning induces transient dramatic changes in intestinal physiology but is also a period of maturation of the intestine.

  10. Effect of tannic acid-fish scale gelatin hydrolysate hybrid nanoparticles on intestinal barrier function and α-amylase activity.

    PubMed

    Wu, Shao-Jung; Ho, Yi-Cheng; Jiang, Shun-Zhou; Mi, Fwu-Long

    2015-07-01

    Practical application of tannic acid is limited because it readily binds proteins to form insoluble aggregates. In this study, tannic acid was self-assembled with fish scale gelatin hydrolysates (FSGH) to form stable colloidal complex nanoparticles. The nanoparticles prepared from 4 mg ml(-1) tannic acid and 4 mg ml(-1) FSGH had a mean particle size of 260.8 ± 3.6 nm, and showed a positive zeta potential (20.4 ± 0.4 mV). The nanoparticles acted as effective nano-biochelators and free radical scavengers because they provided a large number of adsorption sites for interaction with heavy metal ions and scavenging free radicals. The maximum adsorption capacity for Cu(2+) ions was 123.5 mg g(-1) and EC50 of DPPH radical scavenging activity was 21.6 ± 1.2 μg ml(-1). Hydroxyl radical scavenging effects of the nanoparticles were investigated by electron spin resonance spectroscopy. The copper-chelating capacity and free radical scavenging activity of the nanoparticles were associated with their capacity to inhibit Cu(2+) ion-induced barrier impairment and hyperpermeability of Caco-2 intestinal epithelial tight junction (TJ). However, α-amylase inhibitory activity of the nanoparticles was significantly lower than that of free tannic acid. The results suggest that the nanoparticles can ameliorate Cu(2+) ion induced intestinal epithelial TJ dysfunction without severely inhibiting the activity of the digestive enzymes.

  11. Fermented Herbal Formulas KIOM-MA128 Ameliorate IL-6-Induced Intestinal Barrier Dysfunction in Colon Cancer Cell Line

    PubMed Central

    Park, Kwang Il; Kim, Dong Gun; Lee, Bo Hyoung

    2016-01-01

    Inflammatory bowel disease (IBD) comprises Crohn's disease (CD) and ulcerative colitis (UC). IBD increases the risk of colorectal cancer (CRC), depending on the extent and duration of intestinal inflammation. Increased IL-6 expression has been reported in IBD patients, which may be associated with intestinal barrier function through discontinuous tight junction (TJ). KIOM-MA is a specific agent for allergic diseases and cancer, and it is composed of several plants; these herbs have been used in traditional oriental medicine. We fermented KIOM-MA, the product of KIOM-MA128, using probiotics to improve the therapeutic efficacy via the absorption and bioavailability of the active ingredients. In this study, we demonstrated that KIOM-MA/MA128 exhibited anticolitis effects via the modulation of TJ protein. Interleukin-6 resulted in a dose-dependent decrease in the TER and an increase in the FITC-dextran permeability; however, pretreatment with 400 µg/ml KIOM-MA/MA128 resulted in a significant increase in the TER and a decrease in the FITC-dextran permeability via IL-6 induction. Furthermore, protein and mRNA TJ levels remained stable after pretreatment with 400 µg/ml KIOM-MA/MA128. Moreover, KIOM-MA/MA128 suppressed the expression of PLCγ1 and PKC. Taken together, these findings suggest novel information and clue of the anticolitis effects of KIOM-MA128 via regulation of tight junction. PMID:27980357

  12. Saccharomyces cerevisiae strain UFMG 905 protects against bacterial translocation, preserves gut barrier integrity and stimulates the immune system in a murine intestinal obstruction model.

    PubMed

    Generoso, Simone V; Viana, Mirelle; Santos, Rosana; Martins, Flaviano S; Machado, José A N; Arantes, Rosa M E; Nicoli, Jacques R; Correia, Maria I T D; Cardoso, Valbert N

    2010-06-01

    Probiotic is a preparation containing microorganisms that confers beneficial effect to the host. This work assessed whether oral treatment with viable or heat-killed yeast Saccharomyces cerevisiae strain UFMG 905 prevents bacterial translocation (BT), intestinal barrier integrity, and stimulates the immunity, in a murine intestinal obstruction (IO) model. Four groups of mice were used: mice undergoing only laparotomy (CTL), undergoing intestinal obstruction (IO) and undergoing intestinal obstruction after previous treatment with viable or heat-killed yeast. BT, determined as uptake of (99m)Tc-E. coli in blood, mesenteric lymph nodes, liver, spleen and lungs, was significantly higher in IO group than in CTL group. Treatments with both yeasts reduced BT in blood and all organs investigated. The treatment with both yeasts also reduced intestinal permeability as determined by blood uptake of (99m)Tc-DTPA. Immunological data demonstrated that both treatments were able to significantly increase IL-10 levels, but only viable yeast had the same effect on sIgA levels. Intestinal lesions were more severe in IO group when compared to CTL and yeasts groups. Concluding, both viable and heat-killed cells of yeast prevent BT, probably by immunomodulation and by maintaining gut barrier integrity. Only the stimulation of IgA production seems to depend on the yeast viability.

  13. Effect of Lactobacillus Strains on Intestinal Microflora and Mucosa Immunity in Escherichia coli O157:H7-Induced Diarrhea in Mice.

    PubMed

    Bian, Xin; Wang, Ting-Ting; Xu, Min; Evivie, Smith Etareri; Luo, Guang-Wen; Liang, Hong-Zhang; Yu, Shang-Fu; Huo, Gui-Cheng

    2016-07-01

    This study investigated the effects of KLDS 1.8701 and AD1 administrations by gavage on intestinal microflora and mucosal immunity in diarrhea mice infected by Escherichia coli O157:H7 compared to normal mice. The levels of E. coli, Enterobacteria, and Enterococcus decreased significantly (P < 0.05), while viable counts of Lactobacilli and Bifidobacterium increased in diarrhea mice. Moreover, KLDS 1.8701 and AD1 improved secretion of secretory immunoglobulin A and enhanced the levels of interferon-γ and interleukin. Results indicate that KLDS 1.8701 and AD1 could effectively alleviate diarrhea in mice via modulation of intestinal microflora and improve the function of immune system. The study on the effect of KLDS1.8701 and AD1 supplementation in human flora-associated animal models was recommended.

  14. Virulence attenuation of a Mycobacterium avium subspecies paratuberculosis S-type strain prepared from intestinal mucosa after bacterial culture. Evaluation in an experimental ovine model.

    PubMed

    Fernández, Miguel; Delgado, Laetitia; Sevilla, Iker A; Fuertes, Miguel; Castaño, Pablo; Royo, Marcos; Ferreras, M Carmen; Benavides, Julio; Pérez, Valentín

    2015-04-01

    The differences in pathogenicity between an inoculum derived directly from an intestinal tissue homogenate from a paratuberculosis affected sheep and the S-type Mycobacterium avium subsp. partuberculosis (Map) strain isolated in laboratory media from the mentioned homogenate were assessed in two experiments in lambs. Specific peripheral immune responses were significantly lower in animals inoculated with the cultured organisms that showed only granulomatous lesions in the intestinal lymphoid tissue. However, in the homogenate group, more abundant granulomata also occurred in the lamina propria. Map was isolated only in lambs infected with the culture strain. Map DNA was demonstrated by nested-PCR in all the lambs but in a lower proportion (57.1% vs 100%) in those from the culture group. Under these particular experimental conditions, the results suggest that an attenuation of Map virulence has occurred in the cultured strain compared to the initial tissue homogenate, even after a low number of passages.

  15. Effects of Bacillus cereus var. toyoi as probiotic feed supplement on intestinal transport and barrier function in piglets.

    PubMed

    Lodemann, Ulrike; Lorenz, Barbara Martha; Weyrauch, Karl Dietrich; Martens, Holger

    2008-04-01

    The objective of the study was to assess the effects of feed supplementation with the probiotic Bacillus cereus var. toyoi on transport and barrier properties of pig jejunum. Sows and their respective piglets were randomly assigned to two feeding groups: a control group and a probiotic group in which the standard diet was supplemented with Bacillus cereus var. toyoi. At the age of 14, 28, 35 and 56 days, 5 piglets per subgroup were killed and tissue samples from the mid jejunum were mounted in conventional Ussing chambers. Absorptive and secretory properties of the jejunum epithelia were assessed by stimulation of Na-coupled glucose and L-glutamine transport and stimulation of ion secretion by PGE2. Kinetic parameters maximal transport velocity (Vmax) and Michaelis Menten constant (Km) were calculated for glucose and PGE2-stimulated ion secretion. Mannitol fluxes and tissue resistance were measured to evaluate barrier function. With respect to absorption, glucose transport was not changed by treatment and only a slightly higher L-glutamine transport was observed in the probiotic group compared with the control group. The PGE2-stimulated the short circuit current (DeltaIsc) in the small intestine and Vmax were higher in the probiotic group at days 28 and 35 compared with the control group. The probiotic seems to have a stabilising (decreasing) effect on the variability of the data. Changes of absorptive and secretory transport properties dependent on age were observed.

  16. Dietary live yeast and mannan-oligosaccharide supplementation attenuate intestinal inflammation and barrier dysfunction induced by Escherichia coli in broilers.

    PubMed

    Wang, Weiwei; Li, Zhui; Han, Qiqi; Guo, Yuming; Zhang, Bo; D'inca, Romain

    2016-12-01

    The effects of live yeast (LY) and mannan-oligosaccharide (MOS) supplementation on intestinal disruption induced by Escherichia coli in broilers were investigated. The experimental design was a 3×2 factorial arrangement with three dietary treatments (control, 0·5 g/kg LY (Saccharomyces cerevisiae, 1·0×1010 colony-forming units/g), 0·5 g/kg MOS) and two immune treatments (with or without E. coli challenge from 7 to 11 d of age). Samples were collected at 14 d of age. The results showed that E. coli challenge impaired (P<0·05) growth performance during the grower period (1-21 d) and the overall period (1-35 d) of broilers, increased (P<0·05) serum endotoxin and diamine oxidase levels coupled with ileal myeloperoxidase and lysozyme activities, whereas reduced (P<0·05) maltase activity, and compromised the morphological structure of the ileum. Besides, it increased (P<0·05) the mRNA expressions of several inflammatory genes and reduced occludin expression in the ileum. Dietary treatment with both LY and MOS reduced (P<0·05) serum diamine oxidase and ileal myeloperoxidase levels, but elevated villus height (P<0·10) and the ratio of villus height:crypt depth (P<0·05) of the ileum. It also alleviated (P<0·05) E. coli-induced increases (P<0·05) in ileal Toll-like receptor 4, NF-κ B and IL-1 β expressions. Moreover, LY supplementation reduced (P<0·05) feed conversion ratio of birds during the grower period and enhanced (P<0·05) the community diversity (Shannon and Simpson indices) of ileal microbiota, whereas MOS addition counteracted (P<0·05) the decreased ileal IL-10 and occludin expressions in challenged birds. In conclusion, both LY and MOS supplementation could attenuate E. coli-induced intestinal disruption by alleviating intestinal inflammation and barrier dysfunction in broilers. Moreover, LY addition could improve intestinal microbial community structure and feed efficiency of broilers.

  17. Effects of phenol on barrier function of a human intestinal epithelial cell line correlate with altered tight junction protein localization

    SciTech Connect

    McCall, Ingrid C.; Betanzos, Abigail; Weber, Dominique A.; Nava, Porfirio; Miller, Gary W.; Parkos, Charles A.

    2009-11-15

    Phenol contamination of soil and water has raised concerns among people living near phenol-producing factories and hazardous waste sites containing the chemical. Phenol, particularly in high concentrations, is an irritating and corrosive substance, making mucosal membranes targets of toxicity in humans. However, few data on the effects of phenol after oral exposure exist. We used an in vitro model employing human intestinal epithelial cells (SK-CO15) cultured on permeable supports to examine effects of phenol on epithelial barrier function. We hypothesized that phenol disrupts epithelial barrier by altering tight junction (TJ) protein expression. The dose-response effect of phenol on epithelial barrier function was determined using transepithelial electrical resistance (TER) and FITC-dextran permeability measurements. We studied phenol-induced changes in cell morphology and expression of several tight junction proteins by immunofluorescence and Western blot analysis. Effects on cell viability were assessed by MTT, Trypan blue, propidium iodide and TUNEL staining. Exposure to phenol resulted in decreased TER and increased paracellular flux of FITC-dextran in a dose-dependent manner. Delocalization of claudin-1 and ZO-1 from TJs to cytosol correlated with the observed increase in permeability after phenol treatment. Additionally, the decrease in TER correlated with changes in the distribution of a membrane raft marker, suggesting phenol-mediated effects on membrane fluidity. Such observations were independent of effects of phenol on cell viability as enhanced permeability occurred at doses of phenol that did not cause cell death. Overall, these findings suggest that phenol may affect transiently the lipid bilayer of the cell membrane, thus destabilizing TJ-containing microdomains.

  18. Effects of phenol on barrier function of a human intestinal epithelial cell line correlate with altered tight junction protein localization

    PubMed Central

    McCall, Ingrid C.; Betanzos, Abigail; Weber, Dominique A.; Nava, Porfirio; Miller, Gary W.; Parkos, Charles A.

    2010-01-01

    Phenol contamination of soil and water has raised concerns among people living near phenol-producing factories and hazardous waste sites containing the chemical. Phenol, particularly in high concentrations, is an irritating and corrosive substance, making mucosal membranes targets of toxicity in humans. However, few data on the effects of phenol after oral exposure exist. We used an in vitro model employing human intestinal epithelial cells (SK-CO15) cultured on permeable supports to examine effects of phenol on epithelial barrier function. We hypothesized that phenol disrupts epithelial barrier by altering tight junction (TJ) protein expression. The dose-response effect of phenol on epithelial barrier function was determined using transepithelial electrical resistance (TER) and FITC-dextran permeability measurements. We studied phenol-induced changes in cell morphology and expression of several tight junction proteins by immunofluorescence and Western blot analysis. Effects on cell viability were assessed by MTT, Trypan blue, propidium iodide and TUNEL staining. Exposure to phenol resulted in decreased TER and increased paracellular flux of FITC-dextran in a dose-dependent manner. Delocalization of claudin-1 and ZO-1 from TJs to cytosol correlated with the observed increase in permeability after phenol treatment. Additionally, the decrease in TER correlated with changes in the distribution of a membrane raft marker, suggesting phenol-mediated effects on membrane fluidity. Such observations were independent of effects of phenol on cell viability as enhanced permeability occurred at doses of phenol that did not cause cell death. Overall, these findings suggest that phenol may affect transiently the lipid bilayer of the cell membrane, thus destabilizing TJ-containing microdomains. PMID:19679145

  19. Age-related differences in mucosal barrier function and morphology of the small intestine in low and normal birth weight piglets.

    PubMed

    Huygelen, V; De Vos, M; Willemen, S; Fransen, E; Casteleyn, C; Van Cruchten, S; Van Ginneken, C

    2014-08-01

    To test the hypothesis that the mucosal maturation of the small intestine is altered in low birth weight piglets, pairs of naturally suckled low birth weight (LBW, n = 20) and normal birth weight (NBW, n = 20) littermate piglets were selected and sampled after 0, 3, 10, and 28 d of suckling. In vivo intestinal permeability was evaluated via a lactulose-mannitol absorption test. Other indirect measurements for mucosal barrier functioning included sampling for histology and immunohistochemistry (intestinal trefoil factor [ITF]), measuring intestinal alkaline phosphatase (IAP) activity, and immunoblotting for occludin, caspase-3, and proliferating cell nuclear antigen (PCNA). The lactulose-mannitol ratio did not differ between NBW and LBW piglets, but a significant increase in this ratio was observed in 28-d-old piglets (P = 0.001). Small intestinal villus height did not differ with age (P = 0.02) or birth weight (P = 0.20). In contrast, villus width (P = 0.02) and crypt depth (P < 0.05) increased gradually with age, but no birth-weight-related differences were observed. LBW piglets had significantly (P = 0.03) more ITF immunoreactive positive cells per villus area compared to NBW piglets, whereas no age (P = 0.82) or region-related (P = 0.13) differences could be observed. The activity of IAP in the small intestine was higher in newborn piglets compared to the older piglets. No significant differences in cell proliferation in the small intestine was observed (P = 0.47) between NBW and LBW piglets; the highest proliferation was seen in piglets of 28 d of age (P = 0.01). Newborn piglets had significantly fewer apoptotic cells, whereas more apoptotic cells were seen in piglets of 10 d of age (P < 0.01). In conclusion, birth weight did not affect the parameters related to intestinal barrier function investigated in this study, suggesting that the mucosal barrier function is not altered in LBW piglets. Nevertheless, these results confirm that the mucosal barrier function

  20. Intravital autofluorescence 2-photon microscopy of murine intestinal mucosa with ultra-broadband femtosecond laser pulse excitation: image quality, photodamage, and inflammation

    NASA Astrophysics Data System (ADS)

    Klinger, Antje; Krapf, Lisa; Orzekowsky-Schroeder, Regina; Koop, Norbert; Vogel, Alfred; Hüttmann, Gereon

    2015-11-01

    Ultra-broadband excitation with ultrashort pulses may enable simultaneous excitation of multiple endogenous fluorophores in vital tissue. Imaging living gut mucosa by autofluorescence 2-photon microscopy with more than 150 nm broad excitation at an 800-nm central wavelength from a sub-10 fs titanium-sapphire (Ti:sapphire) laser with a dielectric mirror based prechirp was compared to the excitation with 220 fs pulses of a tunable Ti:sapphire laser at 730 and 800 nm wavelengths. Excitation efficiency, image quality, and photochemical damage were evaluated. At similar excitation fluxes, the same image brightness was achieved with both lasers. As expected, with ultra-broadband pulses, fluorescence from NAD(P)H, flavines, and lipoproteins was observed simultaneously. However, nonlinear photodamage apparent as hyperfluorescence with functional and structural alterations of the tissue occurred earlier when the laser power was adjusted to the same image brightness. After only a few minutes, the immigration of polymorphonuclear leucocytes into the epithelium and degranulation of these cells, a sign of inflammation, was observed. Photodamage is promoted by the higher peak irradiances and/or by nonoptimal excitation of autofluorescence at the longer wavelength. We conclude that excitation with a tunable narrow bandwidth laser is preferable to ultra-broadband excitation for autofluorescence-based 2-photon microscopy, unless the spectral phase can be controlled to optimize excitation conditions.

  1. Immunohistochemical localization of adenosine deaminase complexing protein in intestinal mucosa and in colorectal adenocarcinoma as a marker for tumour cell heterogeneity.

    PubMed

    Ten Kate, J; Wijnen, J T; Boldewijn, J; Khan, P M; Bosman, F T

    1985-01-01

    Adenosine deaminase complexing protein (ADCP), a dimeric glycoprotein, has been reported to be decreased or deficient in transformed or cancer-derived cell lines, indicating its potential significance as an indicator of malignant transformation. A similar deficiency was reported in total homogenates of tumours of colon, kidney, lung and liver. In previous biochemical studies we failed to confirm the consistent reduction in ADCP concentration in cancer tissues. A possible explanation for our findings was thought to be intercellular heterogeneity in ADCP expression in individual tumour cells. To study ADCP expression in individual cells, we developed an immunohistochemical method which was applied to tissue sections. Paraformaldehyde--lysine--periodate (PLP) solution was found to be a suitable fixative. Fixed tissue samples were paraffin-embedded, sectioned and stained for ADCP, using an indirect peroxidase-labelled antibody procedure. The protein was localized in normal colonic mucosa, mainly in the brush border region of the luminal epithelium and in cytoplasmic granules. Intense ADCP immunoreactivity was found also in the basal part of some cells. In cancer cells, three staining patterns were observed: membranous, diffuse cytoplasmic and granular cytoplasmic. The adenocarcinomas exhibited significant intratumour and intertumour heterogeneity in their staining types. Further studies on ADCP expression in colorectal cancer in relation to clinical and histopathological characteristics are warranted in order to fully evaluate the potential significance of ADCP as a cancer associated antigen.

  2. Protective effect of the traditional Chinese medicine xuesaitong on intestinal ischemia-reperfusion injury in rats

    PubMed Central

    Xu, Xuan; Li, Dengxiao; Gao, Hong; Gao, Yuejin; Zhang, Long; Du, Yuling; Wu, Jian; Gao, Pengfei

    2015-01-01

    Objective: We investigated the effect of xuesaitong on intestinal barrier dysfunction and related mechanisms in a rat model for intestinal ischemia-reperfusion. Methods: Rats were divided into sham-operated, disease-model and Xuesaitong-treated groups. In the disease-model and Xuesaitong-treated rats an intestinal ischemia-reperfusion injury (IRI) model was introduced, which was created by a temporary obstruction of the superior mesenteric artery (SMA). The xuesaitong group was pre-treated with injections into the abdominal cavity prior to the generation of the IRI model. Tissue changes were evaluated using H&E staining and electron microscopy. Samples were analyzed at 0, 3 and 24 h post IRI. Ascites volumes as well as small intestinal mucosa bleeding, injury scores, wet to dry weight ratios, and propulsions were evaluated. Apoptotic rates were determined with TUNNEL assays. Blood serum tumor necrosis factor-α (TNF-α) levels were measured using ELISA, and Bcl-2 and caspase-3 expression in small intestinal mucosa measured using immunohistochemistry. Results: We determined a significant increase of pathological damage to small intestinal tissues, intestinal wet to dry ratios, ascites volume, TNF-α levels, apoptosis rates of small intestinal mucosa, and expression of Bcl-2 and caspase-3 proteins in the disease-model group compared to the sham-operated group (P < 0.001), and intestinal motility was significantly decreased (P < 0.001). However, comparisons between disease-model and xuesaitong pre-treated animals revealed, that in the treatment group these changes occurred in significant less severities. Conclusions: Xuesaitong can effectively alleviate intestinal barrier dysfunction caused by ischemia-reperfusion injury by reducing TNF-α, up-regulating Bcl-2 and down-regulating caspase-3 expression, in addition to increasing peristalsis. PMID:25932105

  3. Effects of Enterococcus faecium NCIMB 10415 as probiotic supplement on intestinal transport and barrier function of piglets.

    PubMed

    Lodemann, Ulrike; Hübener, Katrin; Jansen, Nicole; Martens, Holger

    2006-02-01

    Many studies report positive effects of probiotic supplementation on the performance and health of piglets. The intention of this study was to describe the effects of Enterococcus faecium NCIMB 10415 on the transport and barrier functions of pig small intestine to improve our understanding of the underlying mechanisms of this probiotic. Ussing chamber studies were conducted with isolated jejunal epithelia of piglets at the age of 14, 28, 35 and 56 days. Jejunal tissues of the control group were compared with epithelia of piglets that had received a diet supplemented with the probiotic Enterococcus faecium NCIMB 10415. Transport properties (absorption and secretion) of the epithelia were examined by mucosal addition of glucose or L-glutamine or by serosal addition of PGE2. Electrophysiology of the epithelia was continuously recorded and the change in short circuit current (Isc) was determined. Paracellular permeability was measured by measuring the flux rates of mannitol. The increase of Isc caused by mucosal addition of glucose was, at all glucose concentrations, higher in the probiotic group compared with the control group. However, the difference (up to 100% of the control) was not significant. The increase of Isc after the mucosal addition of L-glutamine (12mmol/l) was higher in the tissues of the probiotic group but did not reach significance. Serosal PGE2 induced a significantly higher increase of Isc in tissues of the probiotic group at the age of 28 days. No consistent differences were observed in mannitol transport rates between the feeding groups. Significant age-dependent alterations of absorptive and secretory properties of the jejunal epithelium were observed; these were independent of the treatment. A probiotic supplementation seems to influence transport properties of small intestine epithelium. The increased absorption of glucose could be interpreted as a positive effect for the animal.

  4. Cortactin deficiency causes increased RhoA/ROCK1-dependent actomyosin contractility, intestinal epithelial barrier dysfunction, and disproportionately severe DSS-induced colitis.

    PubMed

    Citalán-Madrid, A F; Vargas-Robles, H; García-Ponce, A; Shibayama, M; Betanzos, A; Nava, P; Salinas-Lara, C; Rottner, K; Mennigen, R; Schnoor, M

    2017-01-25

    The intestinal epithelium constitutes a first line of defense of the innate immune system. Epithelial dysfunction is a hallmark of intestinal disorders such as inflammatory bowel diseases (IBDs). The actin cytoskeleton controls epithelial barrier integrity but the function of actin regulators such as cortactin is poorly understood. Given that cortactin controls endothelial permeability, we hypothesized that cortactin is also important for epithelial barrier regulation. We found increased permeability in the colon of cortactin-KO mice that was accompanied by reduced levels of ZO-1, claudin-1, and E-cadherin. By contrast, claudin-2 was upregulated. Cortactin deficiency increased RhoA/ROCK1-dependent actomyosin contractility, and inhibition of ROCK1 rescued the barrier defect. Interestingly, cortactin deficiency caused increased epithelial proliferation without affecting apoptosis. KO mice did not develop spontaneous colitis, but were more susceptible to dextran sulfate sodium colitis and showed severe colon tissue damage and edema formation. KO mice with colitis displayed strong mucus deposition and goblet cell depletion. In healthy human colon tissues, cortactin co-localized with ZO-1 at epithelial cell contacts. In IBDs patients, we observed decreased cortactin levels and loss of co-localization with ZO-1. Thus, cortactin is a master regulator of intestinal epithelial barrier integrity in vivo and could serve as a suitable target for pharmacological intervention in IBDs.Mucosal Immunology advance online publication, 25 January 2017; doi:10.1038/mi.2016.136.

  5. Intestinal barrier function of Atlantic salmon (Salmo salar L.) post smolts is reduced by common sea cage environments and suggested as a possible physiological welfare indicator

    PubMed Central

    2010-01-01

    Background Fish farmed under high intensity aquaculture conditions are subjected to unnatural environments that may cause stress. Therefore awareness of how to maintain good health and welfare of farmed fish is important. For Atlantic salmon held in sea cages, water flow, dissolved oxygen (DO) levels and temperature will fluctuate over time and the fish can at times be exposed to detrimentally low DO levels and high temperatures. This experimental study investigates primary and secondary stress responses of Atlantic salmon post smolts to long-term exposure to reduced and fluctuating DO levels and high water temperatures, mimicking situations in the sea cages. Plasma cortisol levels and cortisol release to the water were assessed as indicators of the primary stress response and intestinal barrier integrity and physiological functions as indicators of secondary responses to changes in environmental conditions. Results Plasma cortisol levels were elevated in fish exposed to low (50% and 60% saturation) DO levels and low temperature (9°C), at days 9, 29 and 48. The intestinal barrier function, measured as electrical resistance (TER) and permeability of mannitol at the end of the experiment, were reduced at 50% DO, in both proximal and distal intestine. When low DO levels were combined with high temperature (16°C), plasma cortisol levels were elevated in the cyclic 1:5 h at 85%:50% DO group and fixed 50% DO group compared to the control (85% DO) group at day 10 but not at later time points. The intestinal barrier function was clearly disturbed in the 50% DO group; TER was reduced in both intestinal regions concomitant with increased paracellular permeability in the distal region. Conclusions This study reveals that adverse environmental conditions (low water flow, low DO levels at low and high temperature), that can occur in sea cages, elicits primary and secondary stress responses in Atlantic salmon post smolts. The intestinal barrier function was significantly

  6. Protective effects of ψ taraxasterol 3-O-myristate and arnidiol 3-O-myristate isolated from Calendula officinalis on epithelial intestinal barrier.

    PubMed

    Dall'Acqua, Stefano; Catanzaro, Daniela; Cocetta, Veronica; Igl, Nadine; Ragazzi, Eugenio; Giron, Maria Cecilia; Cecconello, Laura; Montopoli, Monica

    2016-03-01

    The triterpene esters ᴪ taraxasterol-3-O-myristate (1) and arnidiol-3-O-myristate (2) were tested for their ability to protect epithelial intestinal barrier in an in vitro model. Their effects on ROS production and on trans-epithelial resistance were investigated on CaCo-2 cell monolayers both in basal and stress-induced conditions. Both compounds were able to modulate the stress damage induced by H2O2 and INFγ+TNFα, showing a potential use as model compounds for the study of new therapeutic agents for intestinal inflammations.

  7. Intestinal cytokine response after gut ischemia: role of gut barrier failure.

    PubMed Central

    Grotz, M R; Deitch, E A; Ding, J; Xu, D; Huang, Q; Regel, G

    1999-01-01

    OBJECTIVE: To investigate the effect of intestinal ischemia with and without a reperfusion injury on intestinal cytokine production and gut permeability. SUMMARY BACKGROUND DATA: In humans and in animal models, the gut has been implicated as a cytokine-producing organ after ischemia/reperfusion (I/R)-type injuries. Because of the limitations of in vivo models, it has been difficult to demonstrate directly that the gut releases cytokines after an I/R injury or whether there is a relation between the magnitude of the ischemic process and the cytokine response. METHODS: Ileal mucosal membranes from rats subjected to sham or 45 or 75 min of superior mesenteric occlusion (SMAO) or 45 minutes of SMAO and 30 minutes of reperfusion (SMAO 45/30) were mounted in the Ussing chamber system. Levels of tumor necrosis factor-alpha and interleukin-6 were serially measured in the mucosal and serosal reservoirs of the Ussing system, as was mucosal permeability as reflected by the passage of bacteria or phenol red across the ileal membrane. In a second group of experiments, Escherichia coli C25 was added to the mucosal reservoir to determine if the cytokine response would be increased. RESULTS: Mucosal and serosal levels of tumor necrosis factor-alpha were equally increased after SMAO, with the highest levels in the 75-minute SMAO group. The highest levels of interleukin-6 were found in rats subjected to 75 minutes of SMAO or SMAO 45/30; the serosal levels of interleukin-6 were four to sixfold higher than the mucosal levels. The addition of E. coli C25 resulted in a significant increase in the amount of interleukin-6 or tumor necrosis factor-alpha recovered from the mucosal reservoir. Increased ileal membrane permeability was observed only in rats subjected to 75 minutes of SMAO or SMAO 45/30. CONCLUSION: These results directly document that the levels of tumor necrosis factor-alpha and interleukin-6 released from the gut increase after an ischemic or I/R injury, such as SMAO, and

  8. [Correlation of the microbiota and intestinal mucosa in the pathophysiology and treatment of irritable bowel, irritable eye, and irritable mind syndrome].

    PubMed

    Fehér, János; Kovács, Illés; Pacella, Elena; Radák, Zsolt

    2014-09-14

    Accumulating clinical evidence supports co-morbidity of irritable bowel, irritable eye and irritable mind symptoms. Furthermore, perturbation of the microbiota-host symbiosis (dysbiosis) is considered a common pathogenic mechanism connecting gastrointestinal, ocular and neuropsychiatric symptoms. Consequently, maintaining or restoring microbiota-host symbiosis represents a new approach to treat these symptoms or to prevent their relapses. Current treatment approach assigned a primary role to live probiotics alone or in combination with prebiotics to enhance colonization of beneficial bacteria and to strengthen the symbiosis. However, several papers showed major benefits of heat-killed probiotics as compared to their live counterparts on both intestinal and systemic symptoms. Recently, in addition to killing probiotics, in a proof of concept study lysates (fragments) of probiotics in combination with vitamins A, B, D and omega 3 fatty acids were successfully tested. These findings suggested a conceptual change in the approach addressed to both the microbiota and host as targets for intervention.

  9. Carrageenan Gum and Adherent Invasive Escherichia coli in a Piglet Model of Inflammatory Bowel Disease: Impact on Intestinal Mucosa-associated Microbiota

    PubMed Central

    Munyaka, Peris M.; Sepehri, Shadi; Ghia, Jean-Eric; Khafipour, Ehsan

    2016-01-01

    Inflammatory bowel diseases (IBD) including Crohn's disease (CD), and ulcerative colitis (UC), are chronic conditions characterized by chronic intestinal inflammation. Adherent invasive Escherichia coli (AIEC) pathotype has been increasingly implicated in the etiopathogenesis of IBD. In a 21-day study, we investigated the effects of AIEC strain UM146 inoculation on microbiota profile of the ileal, cecal, ascending and descending colon in a pig model of experimental colitis. Carrageenan gum (CG) was used to induce colitis in weaner piglets whereas AIEC strain UM146 previously isolated from a CD patient was included to investigate a cause or consequence effect in IBD. Treatments were: (1) control; (2) CG; (3) AIEC strain UM146; and (4) CG+UM146. Pigs in groups 2 and 4 received 1% CG in drinking water from day 1 of the study while pigs in groups 3 and 4 were inoculated with UM146 on day 8. Following euthanization on day 21, tissue mucosal scrapings were collected and used for DNA extraction. The V4 region of bacterial 16S rRNA gene was then subjected to Illumina sequencing. Microbial diversity, composition, and the predicted functional metagenome were determined in addition to short chain fatty acids profiles in the digesta and inflammatory cytokines in the intestinal tissue. CG-induced colitis decreased bacterial species richness and shifted community composition. At the phylum level, an increase in Proteobacteria and Deferribacteres and a decrease in Firmicutes, Actinobacteria, and Bacteroidetes were observed in CG and CGUM146 compared to control and UM146. The metabolic capacity of the microbiome was also altered in CG and CGUM146 compared to UM146 and control in the colon. We demonstrated that CG resulted in bacterial dysbiosis and shifted community composition similar to what has been previously observed in IBD patients. However, AIEC strain UM146 alone did not cause any clear changes compared to CG or control in our experimental IBD pig model. PMID:27092122

  10. Transcriptional analysis of porcine intestinal mucosa infected with Salmonella Typhimurium revealed a massive inflammatory response and disruption of bile acid absorption in ileum.

    PubMed

    Uribe, Juber Herrera; Collado-Romero, Melania; Zaldívar-López, Sara; Arce, Cristina; Bautista, Rocío; Carvajal, Ana; Cirera, Susanna; Claros, M Gonzalo; Garrido, Juan J

    2016-01-07

    Infected pork meat is an important source of non-typhoidal human salmonellosis. Understanding of molecular mechanisms involved in disease pathogenesis is important for the development of therapeutic and preventive strategies. Thus, hereby we study the transcriptional profiles along the porcine intestine during infection with Salmonella Typhimurium, as well as post-transcriptional gene modulation by microRNAs (miRNA). Sixteen piglets were orally challenged with S. Typhimurium. Samples from jejunum, ileum and colon, collected 1, 2 and 6 days post infection (dpi) were hybridized to mRNA and miRNA expression microarrays and analyzed. Jejunum showed a reduced transcriptional response indicating mild inflammation only at 2 dpi. In ileum inflammatory genes were overexpressed (e.g., IL-1B, IL-6, IL-8, IL1RAP, TNFα), indicating a strong immune response at all times of infection. Infection also down-regulated genes of the FXR pathway (e.g., NR1H4, FABP6, APOA1, SLC10A2), indicating disruption of the bile acid absorption in ileum. This result was confirmed by decreased high-density lipoprotein cholesterol in serum of infected pigs. Ileal inflammatory gene expression changes peaked at 2 dpi and tended to resolve at 6 dpi. Furthermore, miRNA analysis of ileum at 2 dpi revealed 62 miRNAs potentially regulating target genes involved in this inflammatory process (e.g., miR-374 and miR-451). In colon, genes involved in epithelial adherence, proliferation and cellular reorganization were down-regulated at 2 and 6 dpi. In summary, here we show the transcriptional changes occurring at the intestine at different time points of the infection, which are mainly related to inflammation and disruption of the bile acid metabolism.

  11. Manganese deficiency or excess caused the depression of intestinal immunity, induction of inflammation and dysfunction of the intestinal physical barrier, as regulated by NF-κB, TOR and Nrf2 signalling, in grass carp (Ctenopharyngodon idella).

    PubMed

    Jiang, Wei-Dan; Tang, Ren-Jun; Liu, Yang; Kuang, Sheng-Yao; Jiang, Jun; Wu, Pei; Zhao, Juan; Zhang, Yong-An; Tang, Ling; Tang, Wu-Neng; Zhou, Xiao-Qiu; Feng, Lin

    2015-10-01

    Intestinal mucosal immune components and mRNA levels of inflammatory cytokines, tight junction proteins, antioxidant enzymes and related signalling molecules in young grass carp (Ctenopharyngodon idellus) under dietary manganese (Mn) deficiency or excess were investigated. Fish were fed the diets containing graded levels of Mn [3.65-27.86 mg Mn kg(-1) diet] for 8 weeks. The results demonstrated that Mn deficiency significantly decreased the lysozyme and acid phosphatase (ACP) activities, up-regulated tumour necrosis factor α (TNF-α), interleukin 8 and the signalling factor nuclear factor-κB p65, and down-regulated interleukin 10 (IL-10), transforming growth factor β1, inhibitor of signalling factors κB-α and target of rapamycin mRNA levels in the proximal intestine (PI), mid intestine (MI) and distal intestine (DI). However, Mn deficiency did not change the C3 content in the PI, whereas it decreased the C3 contents in the MI and DI. Additionally, Mn depletion also resulted in significantly low mRNA levels for tight junction proteins (claudin-b, claudin-c, claudin-15, occludin and zonula occludens-1), antioxidant enzymes (MnSOD, GPx and CAT) and NF-E2-related factor-2 in the intestines of fish. Excessive Mn exhibited toxic effects similar to Mn deficiency, where optimal Mn contents reversed those indicators. In conclusion, Mn deficiency or excess causes the depression of intestinal immunity, induction of inflammation and dysfunction of the intestinal physical barrier relating to NF-κB, TOR and Nrf2 signalling in grass carp. Furthermore, quadratic regression analysis at 95% maximum response of lysozyme and acid phosphatase activities in the distal intestine of young grass carp revealed the optimum dietary Mn levels to be 8.90 and 8.99 mg kg(-1) diet, respectively.

  12. Analyzing Beneficial Effects of Nutritional Supplements on Intestinal Epithelial Barrier Functions During Experimental Colitis.

    PubMed

    Vargas Robles, Hilda; Castro Ochoa, Karla Fabiola; Nava, Porfirio; Silva Olivares, Angélica; Shibayama, Mineko; Schnoor, Michael

    2017-01-05

    Inflammatory bowel diseases (IBD), including Crohn's disease and ulcerative colitis, are chronic relapsing disorders of the intestines. They cause severe problems, such as abdominal cramping, bloody diarrhea, and weight loss, in affected individuals. Unfortunately, there is no cure yet, and treatments only aim to alleviate symptoms. Current treatments include anti-inflammatory and immunosuppressive drugs that may cause severe side effects. This warrants the search for alternative treatment options, such as nutritional supplements, that do not cause side effects. Before their application in clinical studies, such compounds must be rigorously tested for effectiveness and security in animal models. A reliable experimental model is the dextran sulfate sodium (DSS) colitis model in mice, which reproduces many of the clinical signs of ulcerative colitis in humans. We recently applied this model to test the beneficial effects of a nutritional supplement containing vitamins C and E, L-arginine, and ω3-polyunsaturated fatty acids (PUFA). We analyzed various disease parameters and found that this supplement was able to ameliorate edema formation, tissue damage, leukocyte infiltration, oxidative stress, and the production of pro-inflammatory cytokines, leading to an overall improvement in the disease activity index. In this article, we explain in detail the correct application of nutritional supplements using the DSS colitis model in C57Bl/6 mice, as well as how disease parameters such as histology, oxidative stress, and inflammation are assessed. Analyzing the beneficial effects of different diet supplements may then eventually open new avenues for the development of alternative treatment strategies that alleviate IBD symptoms and/or that prolong the phases of remission without causing severe side effects.

  13. Enteric glia promote intestinal mucosal healing via activation of focal adhesion kinase and release of proEGF

    PubMed Central

    Van Landeghem, Laurianne; Chevalier, Julien; Mahé, Maxime M.; Wedel, Thilo; Urvil, Petri; Derkinderen, Pascal; Savidge, Tor

    2011-01-01

    Wound healing of the gastrointestinal mucosa is essential for the maintenance of gut homeostasis and integrity. Enteric glial cells play a major role in regulating intestinal barrier function, but their role in mucosal barrier repair remains unknown. The impact of conditional ablation of enteric glia on dextran sodium sulfate (DSS)-induced mucosal damage and on healing of diclofenac-induced mucosal ulcerations was evaluated in vivo in GFAP-HSVtk transgenic mice. A mechanically induced model of intestinal wound healing was developed to study glial-induced epithelial restitution. Glial-epithelial signaling mechanisms were analyzed by using pharmacological inhibitors, neutralizing antibodies, and genetically engineered intestinal epithelial cells. Enteric glial cells were shown to be abundant in the gut mucosa, where they associate closely with intestinal epithelial cells as a distinct cell population from myofibroblasts. Conditional ablation of enteric glia worsened mucosal damage after DSS treatment and significantly delayed mucosal wound healing following diclofenac-induced small intestinal enteropathy in transgenic mice. Enteric glial cells enhanced epithelial restitution and cell spreading in vitro. These enhanced repair processes were reproduced by use of glial-conditioned media, and soluble proEGF was identified as a secreted glial mediator leading to consecutive activation of epidermal growth factor receptor and focal adhesion kinase signaling pathways in intestinal epithelial cells. Our study shows that enteric glia represent a functionally important cellular component of the intestinal epithelial barrier microenvironment and that the disruption of this cellular network attenuates the mucosal healing process. PMID:21350188

  14. Gliadin-specific, HLA-DQ(alpha 1*0501,beta 1*0201) restricted T cells isolated from the small intestinal mucosa of celiac disease patients

    PubMed Central

    1993-01-01

    Celiac disease (CD) is most probably an immunological disease, precipitated in susceptible individuals by ingestion of wheat gliadin and related proteins from other cereals. The disease shows a strong human HLA association predominantly to the cis or trans encoded HLA- DQ(alpha 1*0501,beta 1*0201) (DQ2) heterodimer. T cell recognition of gliadin presented by this DQ heterodimer may thus be of immunopathogenic importance in CD. We therefore challenged small intestinal biopsies from adult CD patients on a gluten-free diet in vitro with gluten (containing both gliadin and other wheat proteins), and isolated activated CD25+ T cells. Polyclonal T cell lines and a panel of T cell clones recognizing gluten were established. They recognized the gliadin moiety of gluten, but not proteins from other cereals. Inhibition studies with anti-HLA antibodies demonstrated predominant antigen presentation by HLA-DQ molecules. The main antigen- presenting molecule was established to be the CD-associated DQ(alpha 1*0501, beta 1*0201) heterodimer. The gluten-reactive T cell clones were CD4+, CD8-, and carried diverse combinations of T cell receptor (TCR) V alpha and V beta chains. The findings suggest preferential mucosal presentation of gluten-derived peptides by HLA-DQ(alpha 1*0501, beta 1*0201) in CD, which may explain the HLA association. PMID:8315377

  15. Food proteins and gut mucosal barrier. IV. Effects of acute and chronic ethanol administration on handling and uptake of bovine serum albumin by rat small intestine

    SciTech Connect

    Stern, M.; Carter, E.A.; Walker, W.A.

    1986-11-01

    The effects of ethanol exposure on small intestinal handling and uptake of radiolabeled bovine serum albumin were investigated using everted gut sacs. There was less breakdown of BSA after acute ethanol administration in vitro and after acute and chronic in vivo exposure. Thus, the vascular compartment of the small intestine was confronted with more complete and potentially more antigenic material after ethanol. Changes in BSA binding and uptake after acute exposure were shown to be reversible after 4-6 hr. In all groups, there was more BSA binding when the small intestine was exposed to ethanol. This difference was most pronounced after chronic exposure. In the same group, uptake of BSA was correlated with binding and significantly increased. Combined effects of ethanol on the gut mucosal barrier may account for changes in food antigen handling and uptake.

  16. Ethanol Impairs Intestinal Barrier Function in Humans through Mitogen Activated Protein Kinase Signaling: A Combined In Vivo and In Vitro Approach

    PubMed Central

    Elamin, Elhaseen; Masclee, Ad; Troost, Freddy; Pieters, Harm-Jan; Keszthelyi, Daniel; Aleksa, Katarina; Dekker, Jan; Jonkers, Daisy

    2014-01-01

    Background Ethanol-induced gut barrier disruption is associated with several gastrointestinal and liver disorders. Aim Since human data on effects of moderate ethanol consumption on intestinal barrier integrity and involved mechanisms are limited, the objectives of this study were to investigate effects of a single moderate ethanol dose on small and large intestinal permeability and to explore the role of mitogen activated protein kinase (MAPK) pathway as a primary signaling mechanism. Methods Intestinal permeability was assessed in 12 healthy volunteers after intraduodenal administration of either placebo or 20 g ethanol in a randomised cross-over trial. Localization of the tight junction (TJ) and gene expression, phosphorylation of the MAPK isoforms p38, ERK and JNK as indicative of activation were analyzed in duodenal biopsies. The role of MAPK was further examined in vitro using Caco-2 monolayers. Results Ethanol increased small and large intestinal permeability, paralleled by redistribution of ZO-1 and occludin, down-regulation of ZO-1 and up-regulation of myosin light chain kinase (MLCK) mRNA expression, and increased MAPK isoforms phosphorylation. In Caco-2 monolayers, ethanol increased permeability, induced redistribution of the junctional proteins and F-actin, and MAPK and MLCK activation, as indicated by phosphorylation of MAPK isoforms and myosin light chain (MLC), respectively, which could be reversed by pretreatment with either MAPK inhibitors or the anti-oxidant L-cysteine. Conclusions Administration of moderate ethanol dosage can increase both small and colon permeability. Furthermore, the data indicate a pivotal role for MAPK and its crosstalk with MLCK in ethanol-induced intestinal barrier disruption. Trial Registration ClinicalTrials.gov NCT00928733 PMID:25226407

  17. Anti-inflammatory and Intestinal Barrier-protective Activities of Commensal Lactobacilli and Bifidobacteria in Thoroughbreds: Role of Probiotics in Diarrhea Prevention in Neonatal Thoroughbreds.

    PubMed

    Tanabe, Soichi; Suzuki, Takuya; Wasano, Yuichiro; Nakajima, Fumihiko; Kawasaki, Hiroshi; Tsuda, Tomonori; Nagamine, Natsuko; Tsurumachi, Takashi; Sugaya, Kiyoshi; Akita, Hiroaki; Takagi, Misako; Takagi, Kunihiko; Inoue, Yoshinobu; Asai, Yo; Morita, Hidetoshi

    2014-01-01

    We previously isolated the commensal bacteria lactobacilli and bifidobacteria from the Thoroughbred intestine and prepared the horse probiotics LacFi(TM), consisting of Lactobacillus ruminis KK14, L. equi KK 15, L. reuteri KK18, L. johnsonii KK21, and Bifidobacterium boum HU. Here, we found that the five LacFi(TM) constituent strains remarkably suppressed pro-inflammatory interleukin-17 production in mouse splenocytes stimulated with interleukin-6 and transforming growth factor-β. The protective effects of the probiotic on impaired intestinal barrier function were evaluated in Caco-2 cells treated with tumor necrosis factor-α. Evaluation of transepithelial resistance showed that all the strains exhibited intestinal barrier protective activity, with significant suppression of barrier impairment by L. reuteri KK18. The LacFi(TM) constituent strains were detected in neonatal LacFi(TM)-administered Thoroughbred feces using polymerase chain reaction denaturing gradient gel electrophoresis and culture methods. These five strains were found to be the predominant lactobacilli and bifidobacteria in the intestinal microbiota of LacFi(TM)-administered Thoroughbreds. Administration of LacFi(TM) to neonatal Thoroughbreds decreased diarrhea incidence from 75.9% in the control group (n=29 neonatal Thoroughbreds) to 30.7% in the LacFi(TM)-administered group (n=101 neonatal Thoroughbreds) immediately after birth to 20 weeks after birth. LacFi(TM) treatment also prevented diarrhea especially at and around 4 weeks and from 10 to 16 weeks. The duration of diarrhea was also shorter in the probiotics-administered group (7.4 ± 0.8 days) than in the control group (14.0 ± 3.2 days). These results indicate that the LacFi(TM) probiotics regulates intestinal function and contributes to diarrhea prevention.

  18. Indomethacin co-crystals and their parent mixtures: does the intestinal barrier recognize them differently?

    PubMed

    Ferretti, Valeria; Dalpiaz, Alessandro; Bertolasi, Valerio; Ferraro, Luca; Beggiato, Sarah; Spizzo, Federico; Spisni, Enzo; Pavan, Barbara

    2015-05-04

    Co-crystals are crystalline complexes of two or more molecules bound together in crystal lattices through noncovalent interactions. The solubility and dissolution properties of co-crystals can allow to increase the bioavailability of poorly water-soluble active pharmaceutical ingredients (APIs). It is currently believed that the co-crystallization strategy should not induce changes on the pharmacological profile of the APIs, even if it is not yet clear whether a co-crystal would be defined as a physical mixture or as a new chemical entity. In order to clarify these aspects, we chose indomethacin as guest poorly aqueous soluble molecule and compared its properties with those of its co-crystals obtained with 2-hydroxy-4-methylpyridine (co-crystal 1), 2-methoxy-5-nitroaniline (co-crystal 2), and saccharine (co-crystal 3). In particular, we performed a systematic comparison among indomethacin, its co-crystals, and their parent physical mixtures by evaluating via HPLC analysis the API dissolution profile, its ability to permeate across intestinal cell monolayers (NCM460), and its oral bioavailability in rat. The indomethacin dissolution profile was not altered by the presence of co-crystallizing agents as physical mixtures, whereas significant changes were observed by the dissolution of the co-crystals. Furthermore, there was a qualitative concordance between the API dissolution patterns and the relative oral bioavailabilities in rats. Co-crystal 1 induced a drastic decrease of the transepithelial electrical resistance (TEER) value of NCM460 cell monolayers, whereas its parent mixture did not evidence any effect. The saccharin-indomethacin mixture induced a drastic decrease of the TEER value of monolayers, whereas its parent co-crystal 3 did not induce any effects on their integrity, being anyway able to increase the permeation of indomethacin. Taken together, these results demonstrate for the first time different effects induced by co-crystals and their parent physical

  19. Moderate Hypothermia Provides Better Protection of the Intestinal Barrier than Deep Hypothermia during Circulatory Arrest in a Piglet Model: A Microdialysis Study

    PubMed Central

    Chen, Guangxian; Tang, Zhixian; Lin, Weibin; Rong, Jian; Wu, Zhongkai

    2016-01-01

    Introduction This study aimed to assess the effects of different temperature settings of hypothermic circulatory arrest (HCA) on intestinal barrier function in a piglet model. Methods Twenty Wuzhishan piglets were randomly assigned to 40 min of HCA at 18°C (DHCA group, n = 5), 40 min of HCA at 24°C (MHCA group, n = 5), normothermic cardiopulmonary bypass (CPB group, n = 5) or sham operation (SO group, n = 5). Serum D-lactate (SDL) and lipopolysaccharide (LPS) levels were determined. Microdialysis parameters (glucose, lactate, pyruvate and glycerol) in the intestinal dialysate were measured. After 180 min of reperfusion, intestinal samples were harvested for real-time polymerase chain reaction and western blotting measurements for E-cadherin and Claudin-1. Results Higher levels of SDL and LPS were detected in the DHCA group than in the MHCA group (P < 0.001). Both MHCA and DHCA groups exhibited lower glucose levels, higher lactate and glycerol levels and a higher lactate to pyruvate (L/P) ratio compared with the CPB group (p<0.05); the DHCA group had higher lactate and glycerol levels and a higher L/P ratio (p<0.05) but similar glucose levels compared to the MHCA group. No significant differences in E-cadherin mRNA or protein levels were noted. Upregulation of claudin-1 mRNA levels was detected in both the DHCA and MHCA animals’ intestines (P < 0.01), but only the DHCA group exhibited a decrease in claudin-1 protein expression (P < 0.01). Conclusion HCA altered the energy metabolism and expression of epithelial junctions in the intestine. Moderate hypothermia (24°C) was less detrimental to the markers of normal functioning of the intestinal barrier than deep hypothermia (18°C). PMID:27685257

  20. The mycotoxin patulin alters the barrier function of the intestinal epithelium: mechanism of action of the toxin and protective effects of glutathione.

    PubMed

    Mahfoud, Radhia; Maresca, Marc; Garmy, Nicolas; Fantini, Jacques

    2002-06-15

    Patulin is a mycotoxin mainly found in apple and apple products. In addition to being toxic for animals, mutagenic, carcinogenic and teratogenic, patulin induces intestinal injuries, including epithelial cell degeneration, inflammation, ulceration, and hemorrhages. In a study of the cellular mechanisms associated with the intestinal toxicity of patulin, two human epithelial intestinal cell lines (HT-29-D4 and Caco-2-14) were exposed to the mycotoxin. Micromolar concentrations of patulin were found to induce a rapid and dramatic decrease of transepithelial resistance (TER) in both cell lines without major signs of toxicity as assessed by the LDH release assay. Since TER reflects the organization of tight junctions, these data indicate that patulin affected the barrier function of the intestinal epithelium. The inhibitory effect of patulin on TER was closely associated with its reactivity for SH groups: (i) cysteine and glutathione prevented the cells from patulin injury; (ii) patulin toxicity was potentiated by buthionine sulfoximine, a specific glutathione-depleting agent; (iii) treatment of the cells with N-ethylmaleimide, a compound known to react with SH groups, resulted in a marked decrease of TER. Moreover, the inhibitory effect of patulin on TER was mimicked and potentiated by phenylarsine oxide, a specific inhibitor of protein tyrosine phosphatase (PTP). This cellular enzyme is a key regulator of intestinal epithelial barrier function. The active site of PTP contains a cysteine residue (Cys215) that is essential for phosphatase activity. Sulfhydryl-reacting compounds such as acetaldehyde decrease TER through covalent modification of Cys215 of PTP. We propose that the toxicity of patulin for intestinal cells involves, among other potential mechanisms, an inactivation of the active site of PTP.

  1. The Role of E-Cadherin in Maintaining the Barrier Function of Corneal Epithelium after Treatment with Cultured Autologous Oral Mucosa Epithelial Cell Sheet Grafts for Limbal Stem Deficiency

    PubMed Central

    Hoft, Richard H.; Wood, Andrew; Oliva, Joan; Niihara, Hope; Makalinao, Andrew; Thropay, Jacquelyn; Pan, Derek; Tiger, Kumar; Garcia, Julio; Laporte, Amanda; French, Samuel W.; Niihara, Yutaka

    2016-01-01

    The role of E-cadherin in epithelial barrier function of cultured autologous oral mucosa epithelial cell sheet (CAOMECS) grafts was examined. CAOMECS were cultured on a temperature-responsive surface and grafted onto rabbit corneas with Limbal Stem Cell Deficiency (LSCD). E-cadherin levels were significantly higher in CAOMECS compared to normal and LSCD epithelium. Beta-catenin colocalized with E-cadherin in CAOMECS cell membranes while phosphorylated beta-catenin was significantly increased. ZO-1, occludin, and Cnx43 were also strongly expressed in CAOMECS. E-cadherin and beta-catenin localization at the cell membrane was reduced in LSCD corneas, while CAOMECS-grafted corneas showed a restoration of E-cadherin and beta-catenin expression. LSCD corneas did not show continuous staining for ZO-1 or for Cnx43, while CAOMECS-grafted corneas showed a positive expression of ZO-1 and Cnx43. Cascade Blue® hydrazide did not pass through CAOMECS. Because E-cadherin interactions are calcium-dependent, EGTA was used to chelate calcium and disrupt cell adhesion. EGTA-treated CAOMECS completely detached from cell culture surface, and E-cadherin levels were significantly decreased. In conclusion, E cadherin high expression contributed to CAOMECS tight and gap junction protein recruitment at the cell membrane, thus promoting cellular adhesion and a functional barrier to protect the ocular surface. PMID:27777792

  2. Short-chain fatty acids activate AMP-activated protein kinase and ameliorate ethanol-induced intestinal barrier dysfunction in Caco-2 cell monolayers.

    PubMed

    Elamin, Elhaseen E; Masclee, Ad A; Dekker, Jan; Pieters, Harm-Jan; Jonkers, Daisy M

    2013-12-01

    Short-chain fatty acids (SCFAs) have been shown to promote intestinal barrier function, but their protective effects against ethanol-induced intestinal injury and underlying mechanisms remain essentially unknown. The aim of the study was to analyze the influence of SCFAs on ethanol-induced barrier dysfunction and to examine the role of AMP-activated protein kinase (AMPK) as a possible mechanism using Caco-2 monolayers. The monolayers were treated apically with butyrate (2, 10, or 20 mmol/L), propionate (4, 20, or 40 mmol/L), or acetate (8, 40, or 80 mmol/L) for 1 h before ethanol (40 mmol/L) for 3 h. Barrier function was analyzed by measurement of transepithelial resistance and permeation of fluorescein isothiocyanate-labeled dextran. Distribution of the tight junction (TJ) proteins zona occludens-1, occludin, and filamentous-actin (F-actin) was examined by immunofluorescence. Metabolic stress was determined by measuring oxidative stress, mitochondrial function, and ATP using dichlorofluorescein diacetate, dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide, and bioluminescence assay, respectively. AMPK was knocked down by small interfering RNA (siRNA), and its activity was assessed by a cell-based ELISA. Exposure to ethanol significantly impaired barrier function compared with controls (P < 0.0001), disrupted TJ and F-actin cytoskeleton integrity, and induced metabolic stress. However, pretreatment with 2 mmol/L butyrate, 4 mmol/L propionate, and 8 mmol/L acetate significantly alleviated the ethanol-induced barrier dysfunction, TJ and F-actin disruption, and metabolic stress compared with ethanol-exposed monolayers (P < 0.0001). The promoting effects on barrier function were abolished by inhibiting AMPK using either compound C or siRNA. These observations indicate that SCFAs exhibit protective effects against ethanol-induced barrier disruption via AMPK activation, suggesting a potential for SCFAs as prophylactic and/or therapeutic factors against ethanol

  3. Modulation of Intestinal Barrier and Bacterial Endotoxin Production Contributes to the Beneficial Effect of Nicotinic Acid on Alcohol-Induced Endotoxemia and Hepatic Inflammation in Rats

    PubMed Central

    Zhong, Wei; Li, Qiong; Zhang, Wenliang; Sun, Qian; Sun, Xinguo; Zhou, Zhanxiang

    2015-01-01

    Alcohol consumption causes nicotinic acid deficiency. The present study was undertaken to determine whether dietary nicotinic acid supplementation provides beneficial effects on alcohol-induced endotoxin signaling and the possible mechanisms at the gut-liver axis. Male Sprague-Dawley rats were pair-fed the Lieber-DeCarli liquid diets containing ethanol or isocaloric maltose dextrin for eight weeks, with or without dietary supplementation with 750 mg/liter nicotinic acid. Chronic alcohol feeding elevated the plasma endotoxin level and activated hepatic endotoxin signaling cascade, which were attenuated by nicotinic acid supplementation. Alcohol consumption remarkably decreased the mRNA levels of claudin-1, claudin-5, and ZO-1 in the distal intestine, whereas nicotinic acid significantly up-regulated these genes. The concentrations of endotoxin, ethanol, and acetaldehyde in the intestinal contents were increased by alcohol exposure, and niacin supplementation reduced the intestinal endotoxin and acetaldehyde levels. Nicotinic acid supplementation upregulated the intestinal genes involved in aldehyde detoxification via transcriptional regulation. These results demonstrate that modulation of the intestinal barrier function and bacterial endotoxin production accounts for the inhibitory effects of nicotinic acid on alcohol-induced endotoxemia and hepatic inflammation. PMID:26501337

  4. TNF-α modulation of intestinal epithelial tight junction barrier is regulated by ERK1/2 activation of Elk-1.

    PubMed

    Al-Sadi, Rana; Guo, Shuhong; Ye, Dongmei; Ma, Thomas Y

    2013-12-01

    Tumor necrosis factor (TNF-α) is a proinflammatory cytokine that plays a critical role in the pathogenesis of inflammatory bowel disease. TNF-α causes an increase in intestinal permeability; however, the signaling pathways and the molecular mechanisms involved remain unclear. The major purpose of this study was to investigate the role of MAP kinase pathways (ERK1/2 and p38 kinase) and the molecular processes involved. An in vitro intestinal epithelial model system consisting of Caco-2 monolayers and an in vivo mouse model system were used to delineate the cellular and molecular mechanisms involved in TNF-α effects on tight junction barrier. The TNF-α-induced increase in Caco-2 tight junction permeability was mediated by activation of the ERK1/2 signaling pathway, but not the p38 kinase pathway. Activation of the ERK1/2 pathway led to phosphorylation and activation of the ETS domain-containing transcription factor Elk-1. The activated Elk-1 translocated to the nucleus, where it bound to its binding motif on the myosin light chain kinase (MLCK) promoter region, leading to the activation of MLCK promoter activity and gene transcription. In addition, in vivo intestinal perfusion studies also indicated that the TNF-α-induced increase in mouse intestinal permeability requires ERK1/2-dependent activation of Elk-1. These studies provide novel insight into the cellular and molecular processes that regulate the TNF-α-induced increase in intestinal epithelial tight junction permeability.

  5. JAM-A regulates permeability and inflammation in the intestine in vivo.

    PubMed

    Laukoetter, Mike G; Nava, Porfirio; Lee, Winston Y; Severson, Eric A; Capaldo, Christopher T; Babbin, Brian A; Williams, Ifor R; Koval, Michael; Peatman, Eric; Campbell, Jacquelyn A; Dermody, Terence S; Nusrat, Asma; Parkos, Charles A

    2007-12-24

    Recent evidence has linked intestinal permeability to mucosal inflammation, but molecular studies are lacking. Candidate regulatory molecules localized within the tight junction (TJ) include Junctional Adhesion Molecule (JAM-A), which has been implicated in the regulation of barrier function and leukocyte migration. Thus, we analyzed the intestinal mucosa of JAM-A-deficient (JAM-A(-/-)) mice for evidence of enhanced permeability and inflammation. Colonic mucosa from JAM-A(-/-) mice had normal epithelial architecture but increased polymorphonuclear leukocyte infiltration and large lymphoid aggregates not seen in wild-type controls. Barrier function experiments revealed increased mucosal permeability, as indicated by enhanced dextran flux, and decreased transepithelial electrical resistance in JAM-A(-/-) mice. The in vivo observations were epithelial specific, because monolayers of JAM-A(-/-) epithelial cells also demonstrated increased permeability. Analyses of other TJ components revealed increased expression of claudin-10 and -15 in the colonic mucosa of JAM-A(-/-) mice and in JAM-A small interfering RNA-treated epithelial cells. Given the observed increase in colonic inflammation and permeability, we assessed the susceptibility of JAM-A(-/-) mice to the induction of colitis with dextran sulfate sodium (DSS). Although DSS-treated JAM-A(-/-) animals had increased clinical disease compared with controls, colonic mucosa showed less injury and increased epithelial proliferation. These findings demonstrate a complex role of JAM-A in intestinal homeostasis by regulating epithelial permeability, inflammation, and proliferation.

  6. The intestinal microbiome, barrier function, and immune system in inflammatory bowel disease: a tripartite pathophysiological circuit with implications for new therapeutic directions

    PubMed Central

    Vindigni, Stephen M.; Zisman, Timothy L.; Suskind, David L.; Damman, Christopher J.

    2016-01-01

    We discuss the tripartite pathophysiological circuit of inflammatory bowel disease (IBD), involving the intestinal microbiota, barrier function, and immune system. Dysfunction in each of these physiological components (dysbiosis, leaky gut, and inflammation) contributes in a mutually interdependent manner to IBD onset and exacerbation. Genetic and environmental risk factors lead to disruption of gut homeostasis: genetic risks predominantly affect the immune system, environmental risks predominantly affect the microbiota, and both affect barrier function. Multiple genetic and environmental ‘hits’ are likely necessary to establish and exacerbate disease. Most conventional IBD therapies currently target only one component of the pathophysiological circuit, inflammation; however, many patients with IBD do not respond to immune-modulating therapies. Hope lies in new classes of therapies that target the microbiota and barrier function. PMID:27366227

  7. The intestinal microbiome, barrier function, and immune system in inflammatory bowel disease: a tripartite pathophysiological circuit with implications for new therapeutic directions.

    PubMed

    Vindigni, Stephen M; Zisman, Timothy L; Suskind, David L; Damman, Christopher J

    2016-07-01

    We discuss the tripartite pathophysiological circuit of inflammatory bowel disease (IBD), involving the intestinal microbiota, barrier function, and immune system. Dysfunction in each of these physiological components (dysbiosis, leaky gut, and inflammation) contributes in a mutually interdependent manner to IBD onset and exacerbation. Genetic and environmental risk factors lead to disruption of gut homeostasis: genetic risks predominantly affect the immune system, environmental risks predominantly affect the microbiota, and both affect barrier function. Multiple genetic and environmental 'hits' are likely necessary to establish and exacerbate disease. Most conventional IBD therapies currently target only one component of the pathophysiological circuit, inflammation; however, many patients with IBD do not respond to immune-modulating therapies. Hope lies in new classes of therapies that target the microbiota and barrier function.

  8. Intestinal permeability and bacterial translocation following small bowel transplantation in the rat

    SciTech Connect

    Grant, D.; Hurlbut, D.; Zhong, R.; Wang, P.Z.; Chen, H.F.; Garcia, B.; Behme, R.; Stiller, C.; Duff, J. )

    1991-08-01

    In addition to its role in absorbing nutrients, the intestinal mucosa provides an important barrier against toxins and bacteria in the bowel lumen. The present study evaluated gut barrier function following orthotopic (in continuity) intestinal grafting in rats. Graft histology, intestinal permeability, and bacterial translocation to the grafted mesenteric lymph nodes, the host's liver, and the host's spleen were assessed on the 3rd, 5th, and 7th postoperative days. The study group received no immunosuppression after allotransplantation. The two control groups included rats with isografts and rats with cyclosporine-treated allografts. On the 7th POD, the study animals had moderate transmural inflammation due to rejection, with normal histology in the isografts and CsA-treated allografts; increased intestinal permeability, measured by urinary excretion of oral 51Cr-EDTA (P less than 0.01); and increased number of bacteria in the MLN and spleen (P less than 0.05). The number of bacteria in the MLN and spleen of the study group positively correlated with the changes in intestinal permeability (P less than 0.05). Rejection of the orthotopic intestinal graft leads to increased intestinal permeability and bacterial translocation from the lumen of the graft to the host's reticuloendothelial system. Measures to improve gut barrier function and antibiotic therapy during rejection episodes may help reduce the incidence of septic complications after intestinal grafting.

  9. Changes in intestinal barrier function and gut microbiota in high-fat diet-fed rats are dynamic and region dependent

    PubMed Central

    Boudry, Gaëlle; Lemay, Danielle G.

    2015-01-01

    A causal relationship between the pathophysiological changes in the gut epithelium and altered gut microbiota with the onset of obesity have been suggested but not defined. The aim of this study was to determine the temporal relationship between impaired intestinal barrier function and microbial dysbiosis in the small and large intestine in rodent high-fat (HF) diet-induced obesity. Rats were fed HF diet (45% fat) or normal chow (C, 10% fat) for 1, 3, or 6 wk; food intake, body weight, and adiposity were measured. Barrier function ex vivo using FITC-labeled dextran (4,000 Da, FD-4) and horseradish peroxidase (HRP) probes in Ussing chambers, gene expression, and gut microbial communities was assessed. After 1 wk, there was an immediate but reversible increase in paracellular permeability, decrease in IL-10 expression, and decrease in abundance of genera within the class Clostridia in the ileum. In the large intestine, HRP flux and abundance of genera within the order Bacteroidales increased with time on the HF diet and correlated with the onset of increased body weight and adiposity. The data show immediate insults in the ileum in response to ingestion of a HF diet, which were rapidly restored and preceded increased passage of large molecules across the large intestinal epithelium. This study provides an understanding of microbiota dysbiosis and gut pathophysiology in diet-induced obesity and has identified IL-10 and Oscillospira in the ileum and transcellular flux in the large intestine as potential early impairments in the gut that might lead to obesity and metabolic disorders. PMID:25747351

  10. Changes in intestinal barrier function and gut microbiota in high-fat diet-fed rats are dynamic and region dependent.

    PubMed

    Hamilton, M Kristina; Boudry, Gaëlle; Lemay, Danielle G; Raybould, Helen E

    2015-05-15

    A causal relationship between the pathophysiological changes in the gut epithelium and altered gut microbiota with the onset of obesity have been suggested but not defined. The aim of this study was to determine the temporal relationship between impaired intestinal barrier function and microbial dysbiosis in the small and large intestine in rodent high-fat (HF) diet-induced obesity. Rats were fed HF diet (45% fat) or normal chow (C, 10% fat) for 1, 3, or 6 wk; food intake, body weight, and adiposity were measured. Barrier function ex vivo using FITC-labeled dextran (4,000 Da, FD-4) and horseradish peroxidase (HRP) probes in Ussing chambers, gene expression, and gut microbial communities was assessed. After 1 wk, there was an immediate but reversible increase in paracellular permeability, decrease in IL-10 expression, and decrease in abundance of genera within the class Clostridia in the ileum. In the large intestine, HRP flux and abundance of genera within the order Bacteroidales increased with time on the HF diet and correlated with the onset of increased body weight and adiposity. The data show immediate insults in the ileum in response to ingestion of a HF diet, which were rapidly restored and preceded increased passage of large molecules across the large intestinal epithelium. This study provides an understanding of microbiota dysbiosis and gut pathophysiology in diet-induced obesity and has identified IL-10 and Oscillospira in the ileum and transcellular flux in the large intestine as potential early impairments in the gut that might lead to obesity and metabolic disorders.

  11. 1-Naphthol metabolism and metabolite transport in the small and large intestine. II: Effect of sulphate and phosphate ion omission, and of 2,6-dichloro-4-nitrophenol in the isolated guinea pig mucosa.

    PubMed

    Sund, R B; Lauterbach, F

    1987-04-01

    A previous study (Sund & Lauterbach 1986) in the isolated guinea pig mucosa showed a complex pattern of 1-naphthol (I) metabolism and metabolite (glucuronide = II and sulphate = III) transport in relation to tissue studied (jejunum and colon) and administration side (lumen versus blood side). In the present paper aspects of I metabolism and II and III transport have been further studied. The experiments involved: Omission of inorganic sulphate in the incubation solution at one particular side or at both sides, to see if and how intestinal sulphoconjugation depended on side of sulphate ion entry, and if II and III efflux might be linked to sulphate ion influx. Similar omission experiments with inorganic phosphate, and Incubation in presence of 2,6-dichloro-4-nitrophenol (IV), a drug claimed to be a selective inhibitor of sulphoconjugation. The experiments showed: In the jejunum, sulphate ion caused a much stronger stimulation of III formation from the lumen than from the blood side, when I was added at the luminal side. In the colon, however, the sulphate ion was more effective on the blood side than on the lumen side, regardless of side at which I was added. More experiments are needed to clarify if conjugate efflux is affected by sulphate ion omission as well. Omission of inorganic phosphate did neither affect I metabolism nor II and III efflux. IV (present at both sides at once) had complex effects, involving inhibition of II and III synthesis as well as their efflux, and, in part, a change in their normal lumen: blood distribution pattern.(ABSTRACT TRUNCATED AT 250 WORDS)

  12. Fermented Pueraria Lobata extract ameliorates dextran sulfate sodium-induced colitis by reducing pro-inflammatory cytokines and recovering intestinal barrier function

    PubMed Central

    Choi, Seungho; Woo, Jong-Kyu; Jang, Yeong-Su; Kang, Ju-Hee; Jang, Jung-Eun; Yi, Tae-Hoo; Park, Sang-Yong; Kim, Sun-Yeou; Yoon, Yeo-Sung

    2016-01-01

    Inflammatory bowel disease is a chronic inflammatory disorder occurring in the gastrointestinal track. However, the efficacy of current therapeutic strategies has been limited and accompanied by side effects. In order to eliminate the limitations, herbal medicines have recently been developed for treatment of IBD. Peuraria Lobata (Peuraria L.) is one of the traditional herbal medicines that have anti-inflammatory effects. Bioavailability of Peuraria L., which is rich in isoflavones, is lower than that of their fermented forms. In this study, we generated fermented Peuraria L. extracts (fPue) and investigated the role of fPue in inflammation and intestinal barrier function in vitro and in vivo. As the mice or intestinal epithelial cells were treated with DSS/fPue, mRNA expression of pro-inflammatory cytokines was reduced and the architecture and expression of tight junction proteins were recovered, compared to the DSS-treated group. In summary, fPue treatment resulted in amelioration of DSS-induced inflammation in the colon, and the disrupted intestinal barrier was recovered as the expression and architecture of tight junction proteins were retrieved. These results suggest that use of fPue could be a new therapeutic strategy for treatment of IBD. PMID:27729931

  13. Evaluation of In Vitro Anti-Inflammatory Activities and Protective Effect of Fermented Preparations of Rhizoma Atractylodis Macrocephalae on Intestinal Barrier Function against Lipopolysaccharide Insult

    PubMed Central

    Bose, Shambhunath; Kim, Hojun

    2013-01-01

    Lipopolysaccharide (LPS), a potent inducer of systemic inflammatory responses, is known to cause impairment of intestinal barrier function. Here, we evaluated the in vitro protective effect of an unfermented formulation of Rhizoma Atractylodis Macrocephalae (RAM), a traditional Chinese herbal medicine widely used in the treatment of many digestive and gastrointestinal disorders, and two fermented preparations of RAM, designated as FRAM-1 (prepared in Luria-Bertani broth) and FRAM-2 (prepared in glucose), on intestinal epithelial cells (IECs) against LPS insult. In general, fermented formulations, especially FRAM-2, but not unfermented RAM, exerted an appreciable protective effect on IECs against LPS-induced perturbation of membrane resistance and permeability. Both fermented formulations exhibited appreciable anti-inflammatory activities in terms of their ability to inhibit LPS-induced gene expression and induced production of a number of key inflammatory mediators and cytokines in RAW 264.7 macrophage cells. However, in most cases, FRAM-2 exhibited stronger anti-inflammatory effects than FRAM-1. Our findings also suggest that suppression of nuclear factor-κβ (NF-κβ) activity might be one of the possible mechanisms by which the fermented RAM exerts its anti-inflammatory effects. Collectively, our results highlight the benefits of using fermented products of RAM to protect against LPS-induced inflammatory insult and impairment in intestinal barrier function. PMID:23573125

  14. The Effector Domain Region of the Vibrio vulnificus MARTX Toxin Confers Biphasic Epithelial Barrier Disruption and Is Essential for Systemic Spread from the Intestine

    PubMed Central

    Gavin, Hannah E.; Beubier, Nike T.

    2017-01-01

    Vibrio vulnificus causes highly lethal bacterial infections in which the Multifunctional Autoprocessing Repeats-in-Toxins (MARTX) toxin product of the rtxA1 gene is a key virulence factor. MARTX toxins are secreted proteins up to 5208 amino acids in size. Conserved MARTX N- and C-terminal repeat regions work in concert to form pores in eukaryotic cell membranes, through which the toxin’s central region of modular effector domains is translocated. Upon inositol hexakisphosphate-induced activation of the of the MARTX cysteine protease domain (CPD) in the eukaryotic cytosol, effector domains are released from the holotoxin by autoproteolytic activity. We previously reported that the native MARTX toxin effector domain repertoire is dispensable for epithelial cellular necrosis in vitro, but essential for cell rounding and apoptosis prior to necrotic cell death. Here we use an intragastric mouse model to demonstrate that the effector domain region is required for bacterial virulence during intragastric infection. The MARTX effector domain region is essential for bacterial dissemination from the intestine, but dissemination occurs in the absence of overt intestinal tissue pathology. We employ an in vitro model of V. vulnificus interaction with polarized colonic epithelial cells to show that the MARTX effector domain region induces rapid intestinal barrier dysfunction and increased paracellular permeability prior to onset of cell lysis. Together, these results negate the inherent assumption that observations of necrosis in vitro directly predict bacterial virulence, and indicate a paradigm shift in our conceptual understanding of MARTX toxin function during intestinal infection. Results implicate the MARTX effector domain region in mediating early bacterial dissemination from the intestine to distal organs–a key step in V. vulnificus foodborne pathogenesis–even before onset of overt intestinal pathology. PMID:28060924

  15. Regulation of intestinal permeability: The role of proteases

    PubMed Central

    Van Spaendonk, Hanne; Ceuleers, Hannah; Witters, Leonie; Patteet, Eveline; Joossens, Jurgen; Augustyns, Koen; Lambeir, Anne-Marie; De Meester, Ingrid; De Man, Joris G; De Winter, Benedicte Y

    2017-01-01

    The gastrointestinal barrier is - with approximately 400 m2 - the human body’s largest surface separating the external environment from the internal milieu. This barrier serves a dual function: permitting the absorption of nutrients, water and electrolytes on the one hand, while limiting host contact with noxious luminal antigens on the other hand. To maintain this selective barrier, junction protein complexes seal the intercellular space between adjacent epithelial cells and regulate the paracellular transport. Increased intestinal permeability is associated with and suggested as a player in the pathophysiology of various gastrointestinal and extra-intestinal diseases such as inflammatory bowel disease, celiac disease and type 1 diabetes. The gastrointestinal tract is exposed to high levels of endogenous and exogenous proteases, both in the lumen and in the mucosa. There is increasing evidence to suggest that a dysregulation of the protease/antiprotease balance in the gut contributes to epithelial damage and increased permeability. Excessive proteolysis leads to direct cleavage of intercellular junction proteins, or to opening of the junction proteins via activation of protease activated receptors. In addition, proteases regulate the activity and availability of cytokines and growth factors, which are also known modulators of intestinal permeability. This review aims at outlining the mechanisms by which proteases alter the intestinal permeability. More knowledge on the role of proteases in mucosal homeostasis and gastrointestinal barrier function will definitely contribute to the identification of new therapeutic targets for permeability-related diseases.

  16. Maturation of the Intestinal Epithelial Barrier in Neonatal Rats Coincides with Decreased FcRn Expression, Replacement of Vacuolated Enterocytes and Changed Blimp-1 Expression

    PubMed Central

    Arévalo Sureda, Ester; Weström, Björn; Pierzynowski, Stefan G.; Prykhodko, Olena

    2016-01-01

    Background The intestinal barrier is immature in newborn mammals allowing for transfer of bioactive macromolecules, e.g. protecting antibodies, from mother’s milk to the blood circulation and in neonatal rodents lasts until weaning. This passage involves the neonatal-Fc-receptor (FcRn) binding IgG in the proximal and highly endocytic vacuolated enterocytes in the distal immature small intestine (SI). Recent studies have suggested an involvement of the transcription factor B-lymphocyte-induced maturation-protein-1 (Blimp-1) in the regulation of SI maturation in mice. Hence, the objective of the present study was to monitor the development of the intestinal barrier function, in relation to Blimp-1 expression during both natural and precociously induced intestinal maturation in rats. Results During the suckling period IgG plasma levels increased, while after gut closure it temporarily decreased. This corresponded to a high expression of FcRn in the proximal SI epithelium and the presence of vacuolated enterocytes in the distal SI. The immature foetal-type epithelium was replaced after weaning or induced precocious maturation, by an adult-type epithelium with FcRnneg cells in the proximal and by non-vacuolated enterocytes in the distal SI. In parallel to this epithelial shift, Blimp-1 expression decreased in the distal SI. Conclusion The switch from foetal- to adult-type epithelium, with decreased proximal expression of FcRn and distal replacement of vacuolated enterocytes, was concurrent in the two SI regions and could be used for monitoring SI maturation in the rat. The changes in expression of Blimp-1 in the distal SI epithelium followed the maturation pattern. PMID:27736989

  17. Modulation of Intestinal Epithelial Defense Responses by Probiotic Bacteria.

    PubMed

    Wan, L Y M; Chen, Z J; Shah, N P; El-Nezami, H

    2016-12-09

    Probiotics are live microorganisms, which when administered in food confer numerous health benefits. In previous studies about beneficial effects of probiotic bacteria to health, particularly in the fields of intestinal mucosa defense responses, specific probiotics, in a strain-dependent manner, show certain degree of potential to reinforce the integrity of intestinal epithelium and/or regulate some immune components. The mechanism of probiotic action is an area of interest. Among all possible routes of modulation by probiotics of intestinal epithelial cell-mediated defense responses, modulations of intestinal barrier function, innate, and adaptive mucosal immune responses, as well as signaling pathways are considered to play important role in the intestinal defense responses against pathogenic bacteria. This review summarizes the beneficial effects of probiotic bacteria to intestinal health together with the mechanisms affected by probiotic bacteria: barrier function, innate, and adaptive defense responses such as secretion of mucins, defensins, trefoil factors, immunoglobulin A (IgA), Toll-like receptors (TLRs), cytokines, gut associated lymphoid tissues, and signaling pathways.

  18. A comparison of linaclotide and lubiprostone dosing regimens on ion transport responses in human colonic mucosa

    PubMed Central

    Kang, Sang Bum; Marchelletta, Ronald R; Penrose, Harrison; Docherty, Michael J; McCole, Declan F

    2015-01-01

    Linaclotide, a synthetic guanylyl cyclase C (GC-C) agonist, and the prostone analog, Lubiprostone, are approved to manage chronic idiopathic constipation and constipation-predominant irritable bowel syndrome. Lubiprostone also protects intestinal mucosal barrier function in ischemia. GC-C signaling regulates local fluid balance and other components of intestinal mucosal homeostasis including epithelial barrier function. The aim of this study was to compare if select dosing regimens differentially affect linaclotide and lubiprostone modulation of ion transport and barrier properties of normal human colonic mucosa. Normal sigmoid colon biopsies from healthy subjects were mounted in Ussing chambers. Tissues were treated with linaclotide, lubiprostone, or vehicle to determine effects on short-circuit current (Isc). Subsequent Isc responses to the cAMP agonist, forskolin, and the calcium agonist, carbachol, were also measured to assess if either drug caused desensitization. Barrier properties were assessed by measuring transepithelial electrical resistance. Isc responses to linaclotide and lubiprostone were significantly higher than vehicle control when administered bilaterally or to the mucosal side only. Single versus cumulative concentrations of linaclotide showed differences in efficacy while cumulative but not single dosing caused desensitization to forskolin. Lubiprostone reduced forskolin responses under all conditions. Linaclotide and lubiprostone exerted a positive effect on TER that was dependent on the dosing regimen. Linaclotide and lubiprostone increase ion transport responses across normal human colon but linaclotide displays increased sensitivity to the dosing regimen used. These findings may have implications for dosing protocols of these agents in patients with constipation. PMID:26038704

  19. A comparison of linaclotide and lubiprostone dosing regimens on ion transport responses in human colonic mucosa.

    PubMed

    Kang, Sang Bum; Marchelletta, Ronald R; Penrose, Harrison; Docherty, Michael J; McCole, Declan F

    2015-03-01

    Linaclotide, a synthetic guanylyl cyclase C (GC-C) agonist, and the prostone analog, Lubiprostone, are approved to manage chronic idiopathic constipation and constipation-predominant irritable bowel syndrome. Lubiprostone also protects intestinal mucosal barrier function in ischemia. GC-C signaling regulates local fluid balance and other components of intestinal mucosal homeostasis including epithelial barrier function. The aim of this study was to compare if select dosing regimens differentially affect linaclotide and lubiprostone modulation of ion transport and barrier properties of normal human colonic mucosa. Normal sigmoid colon biopsies from healthy subjects were mounted in Ussing chambers. Tissues were treated with linaclotide, lubiprostone, or vehicle to determine effects on short-circuit current (I sc). Subsequent I sc responses to the cAMP agonist, forskolin, and the calcium agonist, carbachol, were also measured to assess if either drug caused desensitization. Barrier properties were assessed by measuring transepithelial electrical resistance. I sc responses to linaclotide and lubiprostone were significantly higher than vehicle control when administered bilaterally or to the mucosal side only. Single versus cumulative concentrations of linaclotide showed differences in efficacy while cumulative but not single dosing caused desensitization to forskolin. Lubiprostone reduced forskolin responses under all conditions. Linaclotide and lubiprostone exerted a positive effect on TER that was dependent on the dosing regimen. Linaclotide and lubiprostone increase ion transport responses across normal human colon but linaclotide displays increased sensitivity to the dosing regimen used. These findings may have implications for dosing protocols of these agents in patients with constipation.

  20. Lactobacillus rhamnosus GG supernatant promotes intestinal barrier function, balances Treg and TH17 cells and ameliorates hepatic injury in a mouse model of chronic-binge alcohol feeding.

    PubMed

    Chen, Rui-Cong; Xu, Lan-Man; Du, Shan-Jie; Huang, Si-Si; Wu, He; Dong, Jia-Jia; Huang, Jian-Rong; Wang, Xiao-Dong; Feng, Wen-Ke; Chen, Yong-Ping

    2016-01-22

    Impaired intestinal barrier function plays a critical role in alcohol-induced hepatic injury, and the subsequent excessive absorbed endotoxin and bacterial translocation activate the immune response that aggravates the liver injury. Lactobacillus rhamnosus GG supernatant (LGG-s) has been suggested to improve intestinal barrier function and alleviate the liver injury induced by chronic and binge alcohol consumption, but the underlying mechanisms are still not clear. In this study, chronic-binge alcohol fed model was used to determine the effects of LGG-s on the prevention of alcoholic liver disease in C57BL/6 mice and investigate underlying mechanisms. Mice were fed Lieber-DeCarli diet containing 5% alcohol for 10 days, and one dose of alcohol was gavaged on Day 11. In one group, LGG-s was supplemented along with alcohol. Control mice were fed isocaloric diet. Nine hours later the mice were sacrificed for analysis. Chronic-binge alcohol exposure induced an elevation in liver enzymes, steatosis and morphology changes, while LGG-s supplementation attenuated these changes. Treatment with LGG-s significantly improved intestinal barrier function reflected by increased mRNA expression of tight junction (TJ) proteins and villus-crypt histology in ileum, and decreased Escherichia coli (E. coli) protein level in liver. Importantly, flow cytometry analysis showed that alcohol reduced Treg cell population while increased TH17 cell population as well as IL-17 secretion, which was reversed by LGG-s administration. In conclusion, our findings indicate that LGG-s is effective in preventing chronic-binge alcohol exposure-induced liver injury and shed a light on the importance of the balance of Treg and TH17 cells in the role of LGG-s application.

  1. Rifaximin Alters Intestinal Bacteria and Prevents Stress-Induced Gut Inflammation and Visceral Hyperalgesia in Rats

    PubMed Central

    Xu, Dabo; Gao, Jun; Gillilland, Merritt; Wu, Xiaoyin; Song, Il; Kao, John Y.; Owyang, Chung

    2014-01-01

    Background & Aims Rifaximin is used to treat patients with functional gastrointestinal disorders, but little is known about its therapeutic mechanism. We propose that rifaximin modulates the ileal bacterial community, reduces subclinical inflammation of the intestinal mucosa, and improves gut barrier function to reduce visceral hypersensitivity. Methods We induced visceral hyperalgesia in rats, via chronic water avoidance or repeat restraint stressors, and investigated whether rifaximin altered the gut microbiota, prevented intestinal inflammation, and improved gut barrier function. Quantitative polymerase chain reaction and 454 pyrosequencing were used to analyze bacterial 16S rRNA in ileal contents from the rats. Reverse transcription, immunoblot, and histologic analyses were used to evaluate levels of cytokines, the tight junction protein occludin, and mucosal inflammation, respectively. Intestinal permeability and rectal sensitivity were measured. Results Water avoidance and repeat restraint stress each led to visceral hyperalgesia, accompanied by mucosal inflammation and impaired mucosal barrier function. Oral rifaximin altered the composition of bacterial communities in the ileum (Lactobacillus species became the most abundant) and prevented mucosal inflammation, impairment to intestinal barrier function, and visceral hyperalgesia in response to chronic stress. Neomycin also changed the composition of the ileal bacterial community (Proteobacteria became the most abundant species). Neomycin did not prevent intestinal inflammation or induction of visceral hyperalgesia induced by water avoidance stress. Conclusions Rifaximin alters the bacterial population in the ileum of rats, leading to a relative abundance of Lactobacillus. These changes prevent intestinal abnormalities and visceral hyperalgesia in response to chronic psychological stress. PMID:24161699

  2. Chloride channel ClC- 2 enhances intestinal epithelial tight junction barrier function via regulation of caveolin-1 and caveolar trafficking of occludin.

    PubMed

    Nighot, Prashant K; Leung, Lana; Ma, Thomas Y

    2017-03-01

    Previous studies have demonstrated that the chloride channel ClC-2 plays a critical role in intestinal epithelial tight junction (TJ) barrier function via intracellular trafficking of TJ protein occludin. To study the mechanism of ClC-2-mediated TJ barrier function and intracellular trafficking of occludin, we established ClC-2 over-expressing Caco-2 cell line (Caco-2(CLCN2)) by full length ClC-2 ORF transfection. ClC-2 over-expression (Caco-2(CLCN2)) significantly enhanced TJ barrier (increased TER by ≥2 times and reduced inulin flux by 50%) compared to control Caco-2(pEZ) cells. ClC-2 over-expression (Caco-2(CLCN2)) increased occludin protein level compared to control Caco-2(pEZ) cells. Surface biotinylation assay revealed reduced steady state endocytosis of occludin in Caco-2(CLCN2) cells. Furthermore, ClC-2 over-expression led to reduction in caveolin-1 protein level and diminishment of caveolae assembly. Caveolae disruption increased TJ permeability in control but not ClC-2 over-expressing Caco-2(CLCN2) cells. Selective ClC-2 channel blocker GaTx2 caused an increase in caveolin-1 protein level and reduced occludin level. Delivery of cell permeable caveolin-1 scaffolding domain reduced the occludin protein level. Over all, these results suggest that ClC- 2 enhances TJ barrier function in intestinal epithelial cells via regulation of caveolin-1 and caveolae-mediated trafficking of occludin.

  3. Distribution and Characterisation of Goblet Cells in the Large Intestine of Ostriches during the Pre- and Post-Hatch Period.

    PubMed

    Duritis, I; Mugurevics, A

    2016-12-01

    The role of goblet cell secretion, containing mucopolysaccharides, in the formation of a protective barrier of intestinal mucosa and transportation of the intestinal content has been described quite extensively. However, information on the quality composition of mucopolysaccharides and its changes in the intestinal tract of ostrich chicks, especially in the large intestinal segments, is unavailable. In the current study, ostrich embryos/chicks (n = 6/36) of both sexes were used shortly before hatching and during the first months of the post-hatch period. Tissues for histology were taken from the large intestine: the medium segments of the caecum, proximal and distal parts of colon. By using histochemical reactions, the differentiation of goblet cells as well as chemical composition of mucopolysaccharides was carried out. The cells contained acid (AB+), neutral (PAS+) and mixed (AB/PAS+) mucopolysaccharides. The number of goblet cells in the large intestine per unit area of mucosa increased towards the cloaca, and it was the highest in the distal part of the colon. The qualitative goblet cell composition in different large intestinal parts was different in all ages. In the caecum, goblet cells containing acid and mixed mucopolysaccharides dominate post-hatch, whereas in the colon, goblet cells containing acid mucopolysaccharides predominated. The most rapid changes in the qualitative goblet cell composition occur during the first week post-hatch when in all the intestinal segments the proportion of cells containing acid mucopolysaccharides continuously increased.

  4. The serine protease-mediated increase in intestinal epithelial barrier function is dependent on occludin and requires an intact tight junction.

    PubMed

    Ronaghan, Natalie J; Shang, Judie; Iablokov, Vadim; Zaheer, Raza; Colarusso, Pina; Dion, Sébastien; Désilets, Antoine; Leduc, Richard; Turner, Jerrold R; MacNaughton, Wallace K

    2016-09-01

    Barrier dysfunction is a characteristic of the inflammatory bowel diseases (IBD), Crohn's disease and ulcerative colitis. Understanding how the tight junction is modified to maintain barrier function may provide avenues for treatment of IBD. We have previously shown that the apical addition of serine proteases to intestinal epithelial cell lines causes a rapid and sustained increase in transepithelial electrical resistance (TER), but the mechanisms are unknown. We hypothesized that serine proteases increase barrier function through trafficking and insertion of tight junction proteins into the membrane, and this could enhance recovery of a disrupted monolayer after calcium switch or cytokine treatment. In the canine epithelial cell line, SCBN, we showed that matriptase, an endogenous serine protease, could potently increase TER. Using detergent solubility-based cell fractionation, we found that neither trypsin nor matriptase treatment changed levels of tight junction proteins at the membrane. In a fast calcium switch assay, serine proteases did not enhance the rate of recovery of the junction. In addition, serine proteases could not reverse barrier disruption induced by IFNγ and TNFα. We knocked down occludin in our cells using siRNA and found this prevented the serine protease-induced increase in TER. Using fluorescence recovery after photobleaching (FRAP), we found serine proteases induce a greater mobile fraction of occludin in the membrane. These data suggest that a functional tight junction is needed for serine proteases to have an effect on TER, and that occludin is a crucial tight junction protein in this mechanism.

  5. Glutamine decreases intestinal mucosal injury in a rat model of intestinal ischemia-reperfusion by downregulating HMGB1 and inflammatory cytokine expression

    PubMed Central

    Shu, Xiaoliang; Zhang, Jian; Wang, Qingxiu; Xu, Zengguang; Yu, Tingting

    2016-01-01

    Intestinal ischemia-reperfusion (IR) is a common clinical pathophysiological process that is common in severe trauma, major surgery, and in post-resuscitation. Glutamine (Gln) reduces intestinal IR injury, however, its mechanism of action remains to be determined. High mobility group box 1 (HMGB1) protein, nuclear factor-κB (NF-κB), tumor necrosis factor-α (TNF-α), and interleukin-1 (IL-1) are mediators involved in the pathophysiology of intestinal IR injury. The aim of the present study was to investigate the effects of Gln on the intestinal mucosa of HMGB1 expression following IR to determine whether Gln relieved intestinal IR injury in the intestinal mucosal barrier. Forty-eight Sprague-Dawley rats were included in the present study. A model of intestinal ischemia-reperfusion injury was established by clamping the superior mesenteric artery of the rats to cause ischemia, followed by restoring blood flow. The animals were randomly divided into the control (n=24) and the Gln (n=24) groups for the experiments. The two groups of rats were given enteral nutrition with equal heat, nitrogen (heat 125.4 kJ/kg/day, nitrogen 0.2 g/kg/day). The Gln group of rats was fed with enteral nutrition plus 3% Gln, while the control rats were fed with enteral nutrition plus 3% soybean protein. After 7 days, the HMGB1 and plasma levels of NF-κB, TNF-α, IL-1, Gln, D-lactic acid and diamine oxidase (DAO) were observed. The changes in the morphology of intestinal mucosa were observed using electron microscopy. The plasma levels of TNF-α, IL-1, D-lactic acid and DAO, and the level of HMGB1, NF-κB, TNF-α and IL-1 in intestinal mucosa were significantly higher after IR (p<0.05), while the plasma level of Gln was lower in the two groups. In the control group, the plasma level of IL-1, TNF-α, DAO and D-lactic acid, and that of HMGB1, NF-κB, TNF-α, and IL-1 in intestinal mucosa were significantly higher, while the plasma level of Gln was lower than that prior to modeling on the 3

  6. Pro-inflammatory NF-κB and early growth response gene 1 regulate epithelial barrier disruption by food additive carrageenan in human intestinal epithelial cells.

    PubMed

    Choi, Hye Jin; Kim, Juil; Park, Seong-Hwan; Do, Kee Hun; Yang, Hyun; Moon, Yuseok

    2012-06-20

    The widely used food additive carrageenan (CGN) has been shown to induce intestinal inflammation, ulcerative colitis-like symptoms, or neoplasm in the gut epithelia in animal models, which are also clinical features of human inflammatory bowel disease. In this study, the effects of CGN on pro-inflammatory transcription factors NF-κB and early growth response gene 1 product (EGR-1) were evaluated in terms of human intestinal epithelial barrier integrity. Both pro-inflammatory transcription factors were elevated by CGN and only NF-κB activation was shown to be involved in the induction of pro-inflammatory cytokine interleukin-8. Moreover, the integrity of the in vitro epithelial monolayer under the CGN insult was maintained by both activated pro-inflammatory transcription factors NF-κB and EGR-1. Suppression of NF-κB or EGR-1 aggravated barrier disruption by CGN, which was associated with the reduced gene expression of tight junction component zonula occludens 1 and its irregular localization in the epithelial monolayer.

  7. Effect of thyme essential oil and selenium on intestine integrity and antioxidant status of broilers.

    PubMed

    Placha, I; Takacova, J; Ryzner, M; Cobanova, K; Laukova, A; Strompfova, V; Venglovska, K; Faix, S

    2014-02-01

    1. This study evaluated the duodenal wall integrity, antioxidant status as well as some immunological parameters of broiler chickens supplemented with 0.5 g Thymus vulgaris essential oil (EO)/kg diet and 0.4 mg Se/kg DM (dry matter) derived from sodium selenite. 2. A total of 192 one-d-old randomly divided chickens of both sexes (Ross 308 hybrid broilers) were divided into 4 treatment groups of 48 birds each. 3. The first group was fed on a nutritionally balanced basal diet (BD). The other three groups received BD supplemented with 0.5 g/kg thyme oil, or 0.4 mg Se/kg DM, or both feed additives together. 4. The results for the evaluated feed additives were (1) thyme oil - decreased malondialdehyde (MDA) concentration in duodenal mucosa and kidney, increased immunoglobulin A (IgA) concentration in duodenal mucosa, stimulated phagocytic activity in blood, improved intestinal barrier integrity (2) selenium - increased glutathione peroxidase (GPx) activity in blood and liver as well as thioredoxin reductase (TrxR) activity in duodenal mucosa, liver and in the kidney, (3) EO with selenium - increased thioredoxin reductase (TrxR) activity in duodenal mucosa. 5. These results demonstrated that thyme oil alone showed more effective potential to improve intestinal barrier integrity and antioxidant status as well as evoking an immune response in chickens, than if diets were supplemented with both thyme oil and selenium.

  8. Development of a novel self micro-emulsifying drug delivery system (SMEDDS) for reducing HIV protease inhibitor-induced intestinal epithelial barrier dysfunction

    PubMed Central

    Lei, Bokai; Zha, Weibin; Wang, Yun; Wen, Cong; Stude, Elaine J; Wang, Xuan; Jin, Fang; Wang, Guangji; Zhang, Luyong; Zhou, Huiping

    2010-01-01

    The development of HIV protease inhibitors (PIs) has been one of the most significant advances of the past decade in controlling HIV infection. Unfortunately, the benefits of HIV PIs are compromised by serious side effects. One of the most frequent and deleterious side effects of HIV PIs is severe gastrointestinal (GI) disorders including mucosal erosions, epithelial barrier dysfunction, and leak-flux diarrhea, which occurs in 16–62% of patients on HIV PIs. Although the underlying mechanisms behind HIV PI-associated serious adverse side effects remain to be identified, our recent studies have shown that activation of endoplasmic reticulum (ER) stress response plays a critical role in HIV PI-induced GI complications. The objective of this study was to develop a novel self micro-emulsifying drug delivery system (SMEDDS) using various antioxidants as surfactants and co-surfactants to reduce the GI side effects of the most commonly used HIV PI, ritonavir. The biological activities of this SMSDDS of ritonavir were compared with that of Norvir®, which is currently used in the clinic. Rat normal intestinal epithelial cells (IEC-6) and mouse Raw 264.7 macrophages were used to examine the effect of new SMEDDS of ritonavir on activation of ER stress and oxidative stress. The Sprague-Dawley rats and C57/BL6 mice were used for pharmacokinetic studies and in vivo studies. The intracellular and plasma drug concentrations were determined by HPLC analysis. Activation of ER stress was detected by western blot analysis and secreted alkaline phosphatase (SEAP) reporter assay. Reactive oxygen species (ROS) was measured using dichlorodihydrofluorescein diacetate as a probe. Cell viability was determined by Roche’s cell proliferation reagent WST-1. Protein levels of inflammatory cytokines (TNF-α and IL-6) were determined by Enzyme-linked immunosorbent assays (ELISA). The intestinal permeability was assessed by luminal enteral administration of fluorescein isothiocyanate conjugated

  9. Development of a novel self-microemulsifying drug delivery system for reducing HIV protease inhibitor-induced intestinal epithelial barrier dysfunction.

    PubMed

    Lei, Bokai; Zha, Weibin; Wang, Yun; Wen, Cong; Studer, Elaine J; Wang, Xuan; Jin, Fang; Wang, Guangji; Zhang, Luyong; Zhou, Huiping

    2010-06-07

    The development of HIV protease inhibitors (PIs) has been one of the most significant advances of the past decade in controlling HIV infection. Unfortunately, the benefits of HIV PIs are compromised by serious side effects. One of the most frequent and deleterious side effects of HIV PIs is severe gastrointestinal (GI) disorders including mucosal erosions, epithelial barrier dysfunction, and leak-flux diarrhea, which occurs in 16-62% of patients on HIV PIs. Although the underlying mechanisms behind HIV PI-associated serious adverse side effects remain to be identified, our recent studies have shown that activation of endoplasmic reticulum (ER) stress response plays a critical role in HIV PI-induced GI complications. The objective of this study was to develop a novel self-microemulsifying drug delivery system (SMEDDS) using various antioxidants as surfactants and cosurfactants to reduce the GI side effects of the most commonly used HIV PI, ritonavir. The biological activities of this SMSDDS of ritonavir were compared with that of Norvir, which is currently used in the clinic. Rat normal intestinal epithelial cells (IEC-6) and mouse Raw 264.7 macrophages were used to examine the effect of new SMEDDS of ritonavir on activation of ER stress and oxidative stress. Sprague-Dawley rats and C57/BL6 mice were used for pharmacokinetic studies and in vivo studies. The intracellular and plasma drug concentrations were determined by HPLC analysis. Activation of ER stress was detected by Western blot analysis and secreted alkaline phosphatase (SEAP) reporter assay. Reactive oxygen species (ROS) was measured using dichlorodihydrofluorescein diacetate as a probe. Cell viability was determined by Roche's cell proliferation reagent WST-1. Protein levels of inflammatory cytokines (TNF-alpha and IL-6) were determined by enzyme-linked immunosorbent assays (ELISA). The intestinal permeability was assessed by luminal enteral administration of fluorescein isothiocyanate conjugated dextran

  10. Proteomic changes of the porcine small intestine in response to chronic heat stress.

    PubMed

    Cui, Yanjun; Gu, Xianhong

    2015-12-01

    Acute heat stress (HS) negatively affects intestinal integrity and barrier function. In contrast, chronic mild HS poses a distinct challenge to animals. Therefore, this study integrates biochemical, histological and proteomic approaches to investigate the effects of chronic HS on the intestine in finishing pigs. Castrated male crossbreeds (79.00 ± 1.50 kg BW) were subjected to either thermal neutral (TN, 21 °C; 55% ± 5% humidity; n=8) or HS conditions (30 °C; 55% ± 5% humidity; n=8) for 3 weeks. The pigs were sacrificed after 3 weeks of high environmental exposure and the plasma hormones, the intestinal morphology, integrity, and protein profiles of the jejunum mucosa were determined. Chronic HS reduced the free triiodothyronine (FT3) and GH levels. HS damaged intestinal morphology, increased plasma d-lactate concentrations and decreased alkaline phosphatase activity of intestinal mucosa. Proteome analysis of the jejunum mucosa was conducted by 2D gel electrophoresis and mass spectrometry. Fifty-three intestinal proteins were found to be differentially abundant, 18 of which were related to cell structure and motility, and their changes in abundance could comprise intestinal integrity and function. The down-regulation of proteins involved in tricarboxylic acid cycle (TCA cycle), electron transport chain (ETC), and oxidative phosphorylation suggested that chronic HS impaired energy metabolism and thus induced oxidative stress. Moreover, the changes of ten proteins in abundance related to stress response and defense indicated pigs mediated long-term heat exposure and counteracted its negative effects of heat exposure. These findings have important implications for understanding the effect of chronic HS on intestines.

  11. Protection and Restitution of Gut Barrier by Probiotics: Nutritional and Clinical Implications

    PubMed Central

    Rao, R. K.; Samak, G.

    2013-01-01

    Probiotics are beneficial bacteria present in various dietary components and many of these colonize in the human and animal intestine. In the gut probiotics help the host by assisting in maintenance of normal mucosal homeostasis. Probiotics not only help maintain normal function of the gut mucosa, but also protect mucosa from injurious factors such as toxins, allergens and pathogens. The beneficial effect of probiotics is mediated by multiple mechanisms, including cytoprotection, cell proliferation, cell migration, resistance to apoptosis, synthesis of proteins and gene expression. One of the important cytoprotective effects of probiotics in the intestinal mucosa is to strengthen the epithelial tight junctions and preservation of mucosal barrier function. Probiotics not only enhance barrier function by inducing synthesis and assembly of tight junction proteins, but also preventing disruption of tight junctions by injurious factors. Bioactive factors released by probiotics trigger activation of various cell signaling pathways that lead to strengthening of tight junctions and the barrier function. This article reviews and summarizes the current understanding of various probiotics that are involved in the protection of gut barrier function, highlights the cellular and molecular mechanisms involved in the protective effect and addresses the clinical implications of probiotic supplementation. PMID:24353483

  12. Protection and Restitution of Gut Barrier by Probiotics: Nutritional and Clinical Implications.

    PubMed

    Rao, R K; Samak, G

    2013-05-01

    Probiotics are beneficial bacteria present in various dietary components and many of these colonize in the human and animal intestine. In the gut probiotics help the host by assisting in maintenance of normal mucosal homeostasis. Probiotics not only help maintain normal function of the gut mucosa, but also protect mucosa from injurious factors such as toxins, allergens and pathogens. The beneficial effect of probiotics is mediated by multiple mechanisms, including cytoprotection, cell proliferation, cell migration, resistance to apoptosis, synthesis of proteins and gene expression. One of the important cytoprotective effects of probiotics in the intestinal mucosa is to strengthen the epithelial tight junctions and preservation of mucosal barrier function. Probiotics not only enhance barrier function by inducing synthesis and assembly of tight junction proteins, but also preventing disruption of tight junctions by injurious factors. Bioactive factors released by probiotics trigger activation of various cell signaling pathways that lead to strengthening of tight junctions and the barrier function. This article reviews and summarizes the current understanding of various probiotics that are involved in the protection of gut barrier function, highlights the cellular and molecular mechanisms involved in the protective effect and addresses the clinical implications of probiotic supplementation.

  13. Effects of Supplementation of the Synbiotic Ecologic® 825/FOS P6 on Intestinal Barrier Function in Healthy Humans: A Randomized Controlled Trial

    PubMed Central

    Wilms, E.; Gerritsen, J.; Smidt, H.; Besseling-van der Vaart, I.; Rijkers, G. T.; Garcia Fuentes, A. R.; Masclee, A. A. M.; Troost, F. J.

    2016-01-01

    Background and Aims Probiotics, prebiotics and synbiotics have been suggested as dietary strategies to improve intestinal barrier function. This study aimed to assess the effect of two weeks synbiotic supplementation on intestinal permeability under basal and stressed conditions. Secondary aims were the assessment of two weeks synbiotic supplementation on systemic immune function and gastrointestinal symptoms including defecation pattern. Design Twenty healthy adults completed a double-blind, controlled, randomized, parallel design study. Intervention Groups either received synbiotic (1.5 × 1010 CFU Ecologic® 825 + 10 g fructo-oligosaccharides (FOS P6) per day) or control supplements for two weeks. Outcomes Intestinal segment specific permeability was assessed non-invasively by oral administration of multiple sugar probes and, subsequently, assessing the excretion of these probes in urine. This test was conducted at baseline and at the end of intervention, in the absence and in the presence of an indomethacin challenge. Indomethacin was applied to induce a compromised gut state. Plasma zonulin, cytokines and chemokines were measured at baseline and at the end of intervention. Gastrointestinal symptoms and stool frequency were recorded at baseline and daily during intervention. Results Significantly more male subjects were in the synbiotic group compared to the control group (P = 0.025). Indomethacin significantly increased urinary lactulose/rhamnose ratio versus without indomethacin, both in the control group (P = 0.005) and in the synbiotic group (P = 0.017). Urinary sugar recoveries and ratios, plasma levels of zonulin, cytokines and chemokines, and gastrointestinal symptom scores were not significantly different after control or synbiotic intervention. Stool frequency within the synbiotic group was significantly increased during synbiotic intervention compared to baseline (P = 0.039) and higher compared to control intervention (P = 0.045). Conclusion Two weeks

  14. Chronic social stress in pigs impairs intestinal barrier and nutrient transporter function, and alters neuro-immune mediator and receptor expression

    PubMed Central

    Li, Yihang; Song, Zehe; Kerr, Katelyn A.; Moeser, Adam J.

    2017-01-01

    Psychosocial stress is a major factor driving gastrointestinal (GI) pathophysiology and disease susceptibility in humans and animals. The mechanisms governing susceptibility to stress-induced GI disease remain poorly understood. In the present study, we investigated the influence of chronic social stress (CSS) in pigs, induced by 7 d of chronic mixing/crowding stress, on intestinal barrier and nutrient transport function, corticotropin releasing factor (CRF) signaling and immunological responses. Results from this study showed that CSS resulted in a significant impairment of ileal and colonic barrier function indicated by reduced transepithelial electrical resistance (TER) in the ileum and increased FD4 flux in the ileum (by 0.8 fold) and colon (by 0.7 fold). Ileal sodium glucose linked transporter 1 (SGLT-1) function, measured as glucose-induced changes in short-circuit current (Isc), was diminished (by 52%) in CSS pigs, associated with reduced body weight gain and feed efficiency. Although reductions in SGLT-1 function were observed in CSS pigs, mRNA expression for SGLT-1, villus heights were increased in CSS pigs. Corticotropin releasing factor (CRF) mRNA was upregulated (by 0.9 fold) in the ileum of CSS pigs but not in the colon. Urocortin 2 (Ucn2) mRNA was upregulated (by 1.5 fold) in the colon of CSS pigs, but not in the ileum. In CSS pigs, a downregulation of pro-inflammatory cytokines mRNA (IL1B, TNFA, IL8, and IL6) was observed in both ileum and colon, compared with controls. In contrast CSS induced a marked upregulation of mRNA for IL10 and mast cell chymase gene (CMA1) in the ileum and colon. Together, these data demonstrate that chronic stress in pigs results in significant alterations in intestinal barrier and nutrient transport function and neuro-immune mediator and receptor expression. PMID:28170426

  15. Chronic social stress in pigs impairs intestinal barrier and nutrient transporter function, and alters neuro-immune mediator and receptor expression.

    PubMed

    Li, Yihang; Song, Zehe; Kerr, Katelyn A; Moeser, Adam J

    2017-01-01

    Psychosocial stress is a major factor driving gastrointestinal (GI) pathophysiology and disease susceptibility in humans and animals. The mechanisms governing susceptibility to stress-induced GI disease remain poorly understood. In the present study, we investigated the influence of chronic social stress (CSS) in pigs, induced by 7 d of chronic mixing/crowding stress, on intestinal barrier and nutrient transport function, corticotropin releasing factor (CRF) signaling and immunological responses. Results from this study showed that CSS resulted in a significant impairment of ileal and colonic barrier function indicated by reduced transepithelial electrical resistance (TER) in the ileum and increased FD4 flux in the ileum (by 0.8 fold) and colon (by 0.7 fold). Ileal sodium glucose linked transporter 1 (SGLT-1) function, measured as glucose-induced changes in short-circuit current (Isc), was diminished (by 52%) in CSS pigs, associated with reduced body weight gain and feed efficiency. Although reductions in SGLT-1 function were observed in CSS pigs, mRNA expression for SGLT-1, villus heights were increased in CSS pigs. Corticotropin releasing factor (CRF) mRNA was upregulated (by 0.9 fold) in the ileum of CSS pigs but not in the colon. Urocortin 2 (Ucn2) mRNA was upregulated (by 1.5 fold) in the colon of CSS pigs, but not in the ileum. In CSS pigs, a downregulation of pro-inflammatory cytokines mRNA (IL1B, TNFA, IL8, and IL6) was observed in both ileum and colon, compared with controls. In contrast CSS induced a marked upregulation of mRNA for IL10 and mast cell chymase gene (CMA1) in the ileum and colon. Together, these data demonstrate that chronic stress in pigs results in significant alterations in intestinal barrier and nutrient transport function and neuro-immune mediator and receptor expression.

  16. Intestinal Cell Tight Junctions Limit Invasion of Candida albicans through Active Penetration and Endocytosis in the Early Stages of the Interaction of the Fungus with the Intestinal Barrier

    PubMed Central

    Bon, Fabienne; L’Ollivier, Coralie; Laue, Michael; Holland, Gudrun; Bonnin, Alain; Dalle, Frederic

    2016-01-01

    C. albicans is a commensal yeast of the mucous membranes in healthy humans that can also cause disseminated candidiasis, mainly originating from the digestive tract, in vulnerable patients. It is necessary to understand the cellular and molecular mechanisms of the interaction of C. albicans with enterocytes to better understand the basis of commensalism and pathogenicity of the yeast and to improve the management of disseminated candidiasis. In this study, we investigated the kinetics of tight junction (TJ) formation in parallel with the invasion of C. albicans into the Caco-2 intestinal cell line. Using invasiveness assays on Caco-2 cells displaying pharmacologically altered TJ (i.e. differentiated epithelial cells treated with EGTA or patulin), we were able to demonstrate that TJ protect enterocytes against invasion of C. albicans. Moreover, treatment with a pharmacological inhibitor of endocytosis decreased invasion of the fungus into Caco-2 cells displaying altered TJ, suggesting that facilitating access of the yeast to the basolateral side of intestinal cells promotes endocytosis of C. albicans in its hyphal form. These data were supported by SEM observations of differentiated Caco-2 cells displaying altered TJ, which highlighted membrane protrusions engulfing C. albicans hyphae. We furthermore demonstrated that Als3, a hypha-specific C. albicans invasin, facilitates internalization of the fungus by active penetration and induced endocytosis by differentiated Caco-2 cells displaying altered TJ. However, our observations failed to demonstrate binding of Als3 to E-cadherin as the trigger mechanism of endocytosis of C. albicans into differentiated Caco-2 cells displaying altered TJ. PMID:26933885

  17. DNA Damage and Reactive Nitrogen Species are Barriers to Vibrio cholerae Colonization of the Infant Mouse Intestine

    PubMed Central

    Davies, Bryan W.; Bogard, Ryan W.; Dupes, Nicole M.; Gerstenfeld, Tyler A. I.; Simmons, Lyle A.; Mekalanos, John J.

    2011-01-01

    Ingested Vibrio cholerae pass through the stomach and colonize the small intestines of its host. Here, we show that V. cholerae requires at least two types of DNA repair systems to efficiently compete for colonization of the infant mouse intestine. These results show that V. cholerae experiences increased DNA damage in the murine gastrointestinal tract. Agreeing with this, we show that passage through the murine gut increases the mutation frequency of V. cholerae compared to liquid culture passage. Our genetic analysis identifies known and novel defense enzymes required for detoxifying reactive nitrogen species (but not reactive oxygen species) that are also required for V. cholerae to efficiently colonize the infant mouse intestine, pointing to reactive nitrogen species as the potential cause of DNA damage. We demonstrate that potential reactive nitrogen species deleterious for V. cholerae are not generated by host inducible nitric oxide synthase (iNOS) activity and instead may be derived from acidified nitrite in the stomach. Agreeing with this hypothesis, we show that strains deficient in DNA repair or reactive nitrogen species defense that are defective in intestinal colonization have decreased growth or increased mutation frequency in acidified nitrite containing media. Moreover, we demonstrate that neutralizing stomach acid rescues the colonization defect of the DNA repair and reactive nitrogen species defense defective mutants suggesting a common defense pathway for these mutants. PMID:21379340

  18. Microstructure imaging of human rectal mucosa using multiphoton microscopy

    NASA Astrophysics Data System (ADS)

    Liu, N. R.; Chen, G.; Chen, J. X.; Yan, J.; Zhuo, S. M.; Zheng, L. Q.; Jiang, X. S.

    2011-01-01

    Multiphoton microscopy (MPM) has high resolution and sensitivity. In this study, MPM was used to image microstructure of human rectal mucosa. The morphology and distribution of the main components in mucosa layer, absorptive cells and goblet cells in the epithelium, abundant intestinal glands in the lamina propria and smooth muscle fibers in the muscularis mucosa were clearly monitored. The variations of these components were tightly relevant to the pathology in gastrointestine system, especially early rectal cancer. The obtained images will be helpful for the diagnosis of early colorectal cancer.

  19. Bioengineered vocal fold mucosa for voice restoration.

    PubMed

    Ling, Changying; Li, Qiyao; Brown, Matthew E; Kishimoto, Yo; Toya, Yutaka; Devine, Erin E; Choi, Kyeong-Ok; Nishimoto, Kohei; Norman, Ian G; Tsegyal, Tenzin; Jiang, Jack J; Burlingham, William J; Gunasekaran, Sundaram; Smith, Lloyd M; Frey, Brian L; Welham, Nathan V

    2015-11-18

    Patients with voice impairment caused by advanced vocal fold (VF) fibrosis or tissue loss have few treatment options. A transplantable, bioengineered VF mucosa would address the individual and societal costs of voice-related communication loss. Such a tissue must be biomechanically capable of aerodynamic-to-acoustic energy transfer and high-frequency vibration and physiologically capable of maintaining a barrier against the airway lumen. We isolated primary human VF fibroblasts and epithelial cells and cocultured them under organotypic conditions. The resulting engineered mucosae showed morphologic features of native tissue, proteome-level evidence of mucosal morphogenesis and emerging extracellular matrix complexity, and rudimentary barrier function in vitro. When grafted into canine larynges ex vivo, the mucosae generated vibratory behavior and acoustic output that were indistinguishable from those of native VF tissue. When grafted into humanized mice in vivo, the mucosae survived and were well tolerated by the human adaptive immune system. This tissue engineering approach has the potential to restore voice function in patients with otherwise untreatable VF mucosal disease.

  20. Modulation of intestinal barrier function to ameliorate Salmonella infection in mice by oral administration of fermented milks produced with Lactobacillus plantarum MTCC 5690 - a probiotic strain of Indian gut origin.

    PubMed

    Rokana, Namita; Singh, Rajbir; Mallappa, Rashmi Hogarehalli; Batish, Virender Kumar; Grover, Sunita

    2016-12-01

    Probiotic Lactobacillus plantarum MTCC 5690, a probiotic strain of Indian gut origin, and milk formulations produced with the same were explored in this study as biotherapeutics by evaluating their functional efficacy against Salmonella infection in mice. The efficacy of milk formulations (fermented/unfermented) of MTCC 5690 for enhancement of intestinal barrier function was determined by monitoring the permeability and histopathology of the intestine. Infected mice fed with probiotic Dahi, fermented probiotic drink and sweetened fermented probiotic drink maintained the health and integrity of the intestinal epithelium as compared to those fed with PBS, milk, unfermented probiotic milk and Dahi. Our relative expression data revealed that the changes caused by MTCC 5690 in intestinal barrier function components were established through modulation of the key regulatory receptors Toll-like receptor 2 and Toll-like receptor 4. The results suggest that fermented milks of MTCC 5690 could enhance the defences of the intestinal barrier in enteric infection condition and, therefore, can be explored as a dietary-based strategy to reduce Salmonella infection in the human gut.

  1. Effects of early enteral nutrition on the gastrointestinal motility and intestinal mucosal barrier of patients with burn-induced invasive fungal infection

    PubMed Central

    Zhang, Yu; Gu, Fang; Wang, Fengxian; Zhang, Yuanda

    2016-01-01

    Objective: To evaluate the effects of early enteral nutrition on the gastrointestinal motility and intestinal mucosal barrier of patients with burn-induced invasive fungal infection. Methods: A total of 120 patients with burn-induced invasive fungal infection were randomly divided into an early enteral nutrition (EN) group and a parenteral nutrition (PN) group (n=60). The patients were given nutritional support intervention for 14 days, and the expression levels of serum transferrin, albumin, total protein, endotoxin, D-lactic acid and inflammatory cytokines were detected on the 1st, 7th and 14th days respectively. Results: As the treatment progressed, the levels of serum transferrin, albumin and total protein of the EN group were significantly higher than those of the PN group (P<0.05), while the levels of serum endotoxin and D-lactic acid of the form group were significantly lower (P<0.05). After treatment, the expression levels of IL-6 and TNF-α were decreased in the EN group, which were significantly different from those of the PN group (P<0.05). During treatment, the incidence rates of complications such as abdominal distension, diarrhea, sepsis, nausea, vomiting and gastric retention were similar. The mean healing time of wound surface was 9.34±0.78 days in the EN group and 12.46±2.19 days in the PN group, i.e. such time of the former was significantly shorter than that of the latter (P<0.05). Conclusion: Treating patients having burn-induced invasive fungal infection by early enteral nutrition support with arginine can safely alleviate malnutrition and stress reaction, strengthen cellular immune function and promote wound healing, thereby facilitating the recovery of gastrointestinal motility and the function of intestinal mucosal barrier. PMID:27375697

  2. A Gut Microbial Metabolite of Linoleic Acid, 10-Hydroxy-cis-12-octadecenoic Acid, Ameliorates Intestinal Epithelial Barrier Impairment Partially via GPR40-MEK-ERK Pathway*

    PubMed Central

    Miyamoto, Junki; Mizukure, Taichi; Park, Si-Bum; Kishino, Shigenobu; Kimura, Ikuo; Hirano, Kanako; Bergamo, Paolo; Rossi, Mauro; Suzuki, Takuya; Arita, Makoto; Ogawa, Jun; Tanabe, Soichi

    2015-01-01

    Gut microbial metabolites of polyunsaturated fatty acids have attracted much attention because of their various physiological properties. Dysfunction of tight junction (TJ) in the intestine contributes to the pathogenesis of many disorders such as inflammatory bowel disease. We evaluated the effects of five novel gut microbial metabolites on tumor necrosis factor (TNF)-α-induced barrier impairment in Caco-2 cells and dextran sulfate sodium-induced colitis in mice. 10-Hydroxy-cis-12-octadecenoic acid (HYA), a gut microbial metabolite of linoleic acid, suppressed TNF-α and dextran sulfate sodium-induced changes in the expression of TJ-related molecules, occludin, zonula occludens-1, and myosin light chain kinase. HYA also suppressed the expression of TNF receptor 2 (TNFR2) mRNA and protein expression in Caco-2 cells and colonic tissue. In addition, HYA suppressed the protein expression of TNFR2 in murine intestinal epithelial cells. Furthermore, HYA significantly up-regulated G protein-coupled receptor (GPR) 40 expression in Caco-2 cells. It also induced [Ca2+]i responses in HEK293 cells expressing human GPR40 with higher sensitivity than linoleic acid, its metabolic precursor. The barrier-recovering effects of HYA were abrogated by a GPR40 antagonist and MEK inhibitor in Caco-2 cells. Conversely, 10-hydroxyoctadacanoic acid, which is a gut microbial metabolite of oleic acid and lacks a carbon-carbon double bond at Δ12 position, did not show these TJ-restoring activities and down-regulated GPR40 expression. Therefore, HYA modulates TNFR2 expression, at least partially, via the GPR40-MEK-ERK pathway and may be useful in the treatment of TJ-related disorders such as inflammatory bowel disease. PMID:25505251

  3. Influence of dietary inclusion of Bacillus licheniformis on laying performance, egg quality, antioxidant enzyme activities, and intestinal barrier function of laying hens.

    PubMed

    Lei, K; Li, Y L; Yu, D Y; Rajput, I R; Li, W F

    2013-09-01

    This experiment was conducted to evaluate the effects of dietary inclusion of Bacillus licheniformis on laying performance, egg quality, antioxidant enzyme activities, and intestinal barrier function of laying hens. Hy-Line Variety W-36 hens (n = 540; 28 wk of age) were randomized into 6 groups, each group with 6 replications (n = 15). The control group received the basal diet formulated with maize and soybean meal. The treatment groups received the same basal diets supplemented with 0.01, 0.02, 0.03, 0.06, and 0.09% Bacillus licheniformis powder (2 × 10(10) cfu/g) for an 8-wk trial. The results showed that dietary supplementation with 0.01 and 0.03% B. licheniformis significantly increased egg production and egg mass. However, no significant differences were observed in egg weight, feed consumption, and feed conversion efficiency among the 6 groups. Supplementation with different levels of B. licheniformis was found to be effective in improvement of egg quality by increasing egg shell thickness and strength. Compared with control, d-lactate content, diamine oxidase activity, and adrenocorticotropic hormone level in serum decreased significantly, and the level of estradiol and follicle-stimulating hormone increased significantly in plasma of all the experimental groups. Dietary supplementation with B. licheniformis increased the intestinal villus height and reduced the crypt depth. In conclusion, dietary inclusion of B. licheniformis could improve laying performance and egg quality significantly in a dose-dependent manner by decreasing the stress response, upregulating the growth hormone, and improving intestinal health.

  4. Early Activation of MAPK p44/42 Is Partially Involved in DON-Induced Disruption of the Intestinal Barrier Function and Tight Junction Network

    PubMed Central

    Springler, Alexandra; Hessenberger, Sabine; Schatzmayr, Gerd; Mayer, Elisabeth

    2016-01-01

    Deoxynivalenol (DON), produced by the plant pathogens Fusarium graminearum and Fusarium culmorum, is one of the most common mycotoxins, contaminating cereal and cereal-derived products. Although worldwide contamination of food and feed poses health threats to humans and animals, pigs are particularly susceptible to this mycotoxin. DON derivatives, such as deepoxy-deoxynivalenol (DOM-1), are produced by bacterial transformation of certain intestinal bacteria, which are naturally occurring or applied as feed additives. Intestinal epithelial cells are the initial barrier against these food- and feed-borne toxins. The present study confirms DON-induced activation of MAPK p44/42 and inhibition of p44/42 by MAPK-inhibitor U0126 monoethanolate. Influence of DON and DOM-1 on transepithelial electrical resistance (TEER), viability and expression of seven tight junction proteins (TJ), as well as the potential of U0126 to counteract DON-induced effects, was assessed. While DOM-1 showed no effect, DON significantly reduced TEER of differentiated IPEC-J2 and decreased expression of claudin-1 and -3, while leaving claudin-4; ZO-1, -2, and -3 and occludin unaffected. Inhibition of p44/42 counteracted DON-induced TEER decrease and restored claudin-3, but not claudin-1 expression. Therefore, effects of DON on TEER and claudin-3 are at least partially p44/42 mediated, while effects on viability and claudin-1 are likely mediated via alternative pathways. PMID:27618100

  5. Remodeling of Tight Junctions and Enhancement of Barrier Integrity of the CACO-2 Intestinal Epithelial Cell Layer by Micronutrients.

    PubMed

    Valenzano, Mary Carmen; DiGuilio, Katherine; Mercado, Joanna; Teter, Mimi; To, Julie; Ferraro, Brendan; Mixson, Brittany; Manley, Isabel; Baker, Valerissa; Moore, Beverley A; Wertheimer, Joshua; Mullin, James M

    2015-01-01

    The micronutrients zinc, quercetin, butyrate, indole and berberine were evaluated for their ability to induce remodeling of epithelial tight junctions (TJs) and enhance barrier integrity in the CACO-2 gastrointestinal epithelial cell culture model. All five of these chemically very diverse micronutrients increased transepithelial electrical resistance (Rt) significantly, but only berberine also improved barrier integrity to the non-electrolyte D-mannitol. Increases of Rt as much as 200% of untreated controls were observed. Each of the five micronutrients also induced unique, signature-like changes in TJ protein composition, suggesting multiple pathways (and TJ arrangements) by which TJ barrier function can be enhanced. Decreases in abundance by as much as 90% were observed for claudin-2, and increases of over 300% could be seen for claudins -5 and -7. The exact effects of the micronutrients on barrier integrity and TJ protein composition were found to be highly dependent on the degree of differentiation of the cell layer at the time it was exposed to the micronutrient. The substratum to which the epithelial layer adheres was also found to regulate the response of the cell layer to the micronutrient. The implications of these findings for therapeutically decreasing morbidity in Inflammatory Bowel Disease are discussed.

  6. Characterization of in vitro effects of patulin on intestinal epithelial and immune cells.

    PubMed

    Assunção, R; Alvito, P; Kleiveland, C R; Lea, T E

    2016-05-27

    The intestinal mucosa is the first biological barrier encountered by natural toxins, and could possibly be exposed to high amounts of dietary mycotoxins. Patulin (PAT), a mycotoxin produced by Penicillium spp. during fruit spoilage, is one of the best known enteropathogenic mycotoxins able to alter functions of the intestine (Maresca et al., 2008). This study evaluated the effects of PAT on barrier function of the gut mucosa utilizing the intestinal epithelial cell model Caco-2, and scrutinized immunomodulatory effects using human peripheral blood mononuclear cells (PBMC) and human blood monocyte-derived dendritic cells (moDCs) as test systems. PAT exposure reduced Caco-2 cell viability at concentrations above 12μM. As expected, the integrity of a polarized Caco-2 monolayer was affected by PAT exposure, as demonstrated by a decrease in TER values, becoming more pronounced at 50μM. No effects were detected on the expression levels of the tight junction proteins occludin, claudin-1 and claudin-3 at 50μM. However, the expression of zonula occludens-1 (ZO-1) and myosin light chain 2 (MLC2) declined. Also, levels of phospho-MLC2 (p-MLC2) increased after 24h of exposure to 50μM of PAT. T cell proliferation was highly sensitive to PAT with major effects for concentrations above 10nM of PAT. The same conditions did not affect the maturation of moDC. PAT causes a reduction in Caco-2 barrier function mainly by perturbation of ZO-1 levels and the phosphorylation of MLC. Low doses of PAT strongly inhibited T cell proliferation induced by a polyclonal activator, but had no effect on the maturation of moDC. These results provide new information that strengthens the concept that the epithelium and immune cells of the intestinal mucosa are important targets for the toxic effects of food contaminants like mycotoxins.

  7. [Effects of ischemia and revascularization on the epithelium of the small intestine: study on swine].

    PubMed

    Barthod, F

    1994-05-01

    Ischaemia of the small intestine leads to the destruction of the intestinal mucosa. The capacity of the epithelium to regenerate is proportional to the duration of revascularization. The aim of this work was to analyze the kinetic aspects of intestinal epithelial regeneration after destruction due to prolonged ischaemia. This study was conducted in 44 animals (swine) after development of an ischaemia-revascularization protocol of a jejunal loop and bipolar secondary cutaneous exteriorization. After a first series with ischaemia times of 1, 2, 3 and 4 hours, the 4 hour period of ischaemia was chosen for further analysis of the regeneration kinetics over a period of 21 days since it leads to regular and total destruction of the epithelium compatible with regeneration. This analysis included (1) a histological examination (semi-thin slices), (2) immunofluorescent detection of intestinal brush border proteins on frozen slices (villin, saccharase-isomaltase, aminopeptidase N, dipeptidylpeptidase-IV) and mucines, (3) measurement of specific intestinal hydrolase activities (saccharase, aminopeptidase N, dipeptidylpeptidase-IV and alkaline phosphatase) in enriched brush border fractions, and (4) an analysis of variations in intestinal flora. After the 4 hour ischaemia, total destruction of the epithelium with disappearance of the villin and intestinal hydrolases and disorganization of the mucosa invaded by mucosal lacks was observed. Epithelial regeneration was rapid and two days later the histological aspect of the mucosa showed apical expression (still discontinuous), villin and intestinal hydrolase activity. Luminal apical expression of the markers became continuous on day 4, demonstrating the total recovery of the intestinal barrier as confirmed by stable microbial flora. Mucine expression also returned to normal. This regeneration was however incomplete since the mucosa was seen to be flat, without villosities. Immunofluorescence showed the weak intensity of brush

  8. Intestinal Epithelial Stem/Progenitor Cells Are Controlled by Mucosal Afferent Nerves

    PubMed Central

    Lundgren, Ove; Jodal, Mats; Jansson, Madeleine; Ryberg, Anders T.; Svensson, Lennart

    2011-01-01

    Background The maintenance of the intestinal epithelium is of great importance for the survival of the organism. A possible nervous control of epithelial cell renewal was studied in rats and mice. Methods Mucosal afferent nerves were stimulated by exposing the intestinal mucosa to capsaicin (1.6 mM), which stimulates intestinal external axons. Epithelial cell renewal was investigated in the jejunum by measuring intestinal thymidine kinase (TK) activity, intestinal 3H-thymidine incorporation into DNA, and the number of crypt cells labeled with BrdU. The influence of the external gut innervation was minimized by severing the periarterial nerves. Principal Findings Luminal capsaicin increased all the studied variables, an effect nervously mediated to judge from inhibitory effects on TK activity or 3H-thymidine incorporation into DNA by exposing the mucosa to lidocaine (a local anesthetic) or by giving four different neurotransmitter receptor antagonists i.v. (muscarinic, nicotinic, neurokinin1 (NK1) or calcitonin gene related peptide (CGRP) receptors). After degeneration of the intestinal external nerves capsaicin did not increase TK activity, suggesting the involvement of an axon reflex. Intra-arterial infusion of Substance P (SP) or CGRP increased intestinal TK activity, a response abolished by muscarinic receptor blockade. Immunohistochemistry suggested presence of M3 and M5 muscarinic receptors on the intestinal stem/progenitor cells. We propose that the stem/progenitor cells are controlled by cholinergic nerves, which, in turn, are influenced by mucosal afferent neuron(s) releasing acetylcholine and/or SP and/or CGRP. In mice lacking the capsaicin receptor, thymidine incorporation into DNA and number of crypt cells labeled with BrdU was lower than in wild type animals suggesting that nerves are important also in the absence of luminal capsaicin, a conclusion also supported by the observation that atropine lowered thymidine incorporation into DNA by 60% in control

  9. Theaflavins enhance intestinal barrier of Caco-2 Cell monolayers through the expression of AMP-activated protein kinase-mediated Occludin, Claudin-1, and ZO-1.

    PubMed

    Park, Ha-Young; Kunitake, Yuri; Hirasaki, Naoto; Tanaka, Mitsuru; Matsui, Toshiro

    2015-01-01

    We investigated the effect of theaflavins (TFs) on membrane barrier of Caco-2 cells. For fluorescein-transport experiments, the apparent permeability (Papp) of fluorescein in Caco-2 cells pretreated with 20 μM TFs were significantly decreased compared with that in untreated cells. Although the respective monomeric catechins did not show any Papp reduction, purpurogallin pretreatment resulted in a significant Papp reduction similar to that of TF-3'-O-gallate (TF3'G) pretreatment. This indicates that the benzotropolone moiety may play a crucial role in the Papp reduction or tight junction (TJ)-closing effect induced by TFs. In TF-3'-O-gallate-pretreated Caco-2 cells, fluorescein transport was completely restored by compound C (AMPK inhibitor). In addition, TF3'G significantly increased both the mRNA and protein expression of TJ-related proteins (occludin, claudin-1, and ZO-1) as well as the phosphorylation of AMPK. It was, thus, concluded that TFs could enhance intestinal barrier function by increasing the expression of TJ-related proteins through the activation of AMPK in Caco-2 cells.

  10. Beneficial role of the probiotic mixture Ultrabiotique on maintaining the integrity of intestinal mucosal barrier in DSS-induced experimental colitis.

    PubMed

    Toumi, Ryma; Abdelouhab, Katia; Rafa, Hayet; Soufli, Imene; Raissi-Kerboua, Djamila; Djeraba, Zineb; Touil-Boukoffa, Chafia

    2013-06-01

    The etiology of inflammatory bowel diseases which include ulcerative colitis (UC) and Crohn disease has not yet been clarified. Several hypotheses suggest a change in composition of gut microflora along with an impaired mucosal barrier that lead to excessive mucosal immunologic responses. Increased production of nitric oxide (NO) contributes greatly to the tissue injury caused by chronic inflammation. Evidence indicates that the mucus layer covering the epithelium is altered during UC and experimental colitis. Our aim in this study was to investigate the potential therapeutic effect of probiotic during DSS-induced colitis by modulating the immune system and colonic mucus production. For that purpose, the probiotic formulation Ultrabiotique(®) (Lactobacillus acidophilus, Bifidobacterium lactis, Lactobacillus plantarum and Bifidobacterium breve) was administered daily for 7 d to mice with colitis. Probiotic supplementation improved clinical symptoms and histological alterations observed during DSS induced colitis. Ultrabiotique(®) treatment down regulated the NO production by peritoneal macrophages of DSS-treated mice and enhanced mucus production in both DSS-treated and healthy mice. In conclusion, the modification of microflora by the Ultrabiotique(®) played a beneficial role in maintaining the integrity of the intestinal mucosal barrier and promoted tissue repair.

  11. Prions efficiently cross the intestinal barrier after oral administration: Study of the bioavailability, and cellular and tissue distribution in vivo

    PubMed Central

    Urayama, Akihiko; Concha-Marambio, Luis; Khan, Uffaf; Bravo-Alegria, Javiera; Kharat, Vineetkumar; Soto, Claudio

    2016-01-01

    Natural forms of prion diseases frequently originate by oral (p.o.) infection. However, quantitative information on the gastro-intestinal (GI) absorption of prions (i.e. the bioavailability and subsequent biodistribution) is mostly unknown. The main goal of this study was to evaluate the fate of prions after oral administration, using highly purified radiolabeled PrPSc. The results showed a bi-phasic reduction of PrPSc with time in the GI, except for the ileum and colon which showed sustained increases peaking at 3–6 hr, respectively. Plasma and whole blood 125I-PrPSc reached maximal levels by 30 min and 3 hr, respectively, and blood levels were constantly higher than plasma. Upon crossing the GI-tract 125I-PrPSc became associated to blood cells, suggesting that binding to cells decreased the biological clearance of the agent. Size-exclusion chromatography revealed that oligomeric 125I-PrPSc were transported from the intestinal tract, and protein misfolding cyclic amplification showed that PrPSc in organs and blood retained the typical prion self-replicating ability. Pharmacokinetic analysis found the oral bioavailability of 125I-PrPSc to be 33.6%. Interestingly, 125I-PrPSc reached the brain in a quantity equivalent to the minimum amount needed to initiate prion disease. Our findings provide a comprehensive and quantitative study of the fate of prions upon oral infection. PMID:27573341

  12. From Intestinal Permeability to Dysmotility: The Biobreeding Rat as a Model for Functional Gastrointestinal Disorders

    PubMed Central

    Vanheel, Hanne; Masaoka, Tatsuhiro; Salim Rasoel, Shadea; Tóth, Joran; Houben, Els; Verbeke, Kristin; De Hertogh, Gert; Berghe, Pieter Vanden; Tack, Jan; Farré, Ricard

    2014-01-01

    Background Impaired intestinal barrier function, low-grade inflammation and altered neuronal control are reported in functional gastrointestinal disorders. However, the sequence of and causal relation between these events is unclear, necessitating a spontaneous animal model. The aim of this study was to describe the natural history of intestinal permeability, mucosal and neuromuscular inflammation and nitrergic motor neuron function during the lifetime of the BioBreeding (BB) rat. Methods Normoglycemic BB-diabetes prone (DP) and control rats were sacrificed at different ages and jejunum was harvested to characterize intestinal permeability, inflammation and neuromuscular function. Results Both structural and functional evidence of increased intestinal permeability was found in young BB-DP rats from the age of 50 days. In older animals, starting in the mucosa from 70 days and in half of the animals also in the muscularis propria from 110 days, an inflammatory reaction, characterized by an influx of polymorphonuclear cells and higher myeloperoxidase activity, was observed. Finally, in animals older than 110 days, coinciding with a myenteric ganglionitis, a loss of nitrergic neurons and motor function was demonstrated. Conclusion In the BB-rat, mucosal inflammatory cell infiltration is preceded by intestinal barrier dysfunction and followed by myenteric ganglionitis and loss of nitrergic function. This sequence supports a primary role for impaired barrier function and provides an insightful model for the pathogenesis of functional gastrointestinal disorders. PMID:25354336

  13. Toxic Effects of Maternal Zearalenone Exposure on Intestinal Oxidative Stress, Barrier Function, Immunological and Morphological Changes in Rats

    PubMed Central

    Liu, Min; Gao, Rui; Meng, Qingwei; Zhang, Yuanyuan; Bi, Chongpeng; Shan, Anshan

    2014-01-01

    The present study was conducted to investigate the effects of maternal zearalenone (ZEN) exposure on the intestine of pregnant Sprague-Dawley (SD) rats and its offspring. Ninety-six pregnant SD rats were randomly divided into four groups and were fed with diets containing ZEN at concentrations of 0.3 mg/kg, 48.5 mg/kg, 97.6 mg/kg or 146.0 mg/kg from gestation days (GD) 1 to 7. All rats were fed with mycotoxin-free diet until their offspring were weaned at three weeks of age. The small intestinal fragments from pregnant rats at GD8, weaned dams and pups were collected and studied for toxic effects of ZEN on antioxidant status, immune response, expression of junction proteins, and morphology. The results showed that ZEN induced oxidative stress, affected the villous structure and reduced the expression of junction proteins claudin-4, occludin and connexin43 (Cx43) in a dose-dependent manner in pregnant rats. Different effects on the expression of cytokines were also observed both in mRNA and protein levels in these pregnant groups. Ingestion of high levels of ZEN caused irreversible damage in weaned dams, such as oxidative stress, decreased villi hight and low expression of junction proteins and cytokines. Decreased expression of jejunal interleukin-8 (IL-8) and increased expression of gastrointestinal glutathione peroxidase (GPx2) mRNA were detected in weaned offspring, indicating long-term damage caused by maternal ZEN. We also found that the Nrf2 expression both in mRNA and protein levels were up-regulated in the ZEN-treated groups of pregnant dams and the high-dose of ZEN group of weaned dams. The data indicate that modulation of Nrf2-mediated pathway is one of mechanism via which ZEN affects gut wall antioxidant and inflammatory responses. PMID:25180673

  14. Toxic effects of maternal zearalenone exposure on intestinal oxidative stress, barrier function, immunological and morphological changes in rats.

    PubMed

    Liu, Min; Gao, Rui; Meng, Qingwei; Zhang, Yuanyuan; Bi, Chongpeng; Shan, Anshan

    2014-01-01

    The present study was conducted to investigate the effects of maternal zearalenone (ZEN) exposure on the intestine of pregnant Sprague-Dawley (SD) rats and its offspring. Ninety-six pregnant SD rats were randomly divided into four groups and were fed with diets containing ZEN at concentrations of 0.3 mg/kg, 48.5 mg/kg, 97.6 mg/kg or 146.0 mg/kg from gestation days (GD) 1 to 7. All rats were fed with mycotoxin-free diet until their offspring were weaned at three weeks of age. The small intestinal fragments from pregnant rats at GD8, weaned dams and pups were collected and studied for toxic effects of ZEN on antioxidant status, immune response, expression of junction proteins, and morphology. The results showed that ZEN induced oxidative stress, affected the villous structure and reduced the expression of junction proteins claudin-4, occludin and connexin43 (Cx43) in a dose-dependent manner in pregnant rats. Different effects on the expression of cytokines were also observed both in mRNA and protein levels in these pregnant groups. Ingestion of high levels of ZEN caused irreversible damage in weaned dams, such as oxidative stress, decreased villi hight and low expression of junction proteins and cytokines. Decreased expression of jejunal interleukin-8 (IL-8) and increased expression of gastrointestinal glutathione peroxidase (GPx2) mRNA were detected in weaned offspring, indicating long-term damage caused by maternal ZEN. We also found that the Nrf2 expression both in mRNA and protein levels were up-regulated in the ZEN-treated groups of pregnant dams and the high-dose of ZEN group of weaned dams. The data indicate that modulation of Nrf2-mediated pathway is one of mechanism via which ZEN affects gut wall antioxidant and inflammatory responses.

  15. Quantitative In Vitro and In Vivo Evaluation of Intestinal and Blood-Brain Barrier Transport Kinetics of the Plant N-Alkylamide Pellitorine

    PubMed Central

    Veryser, Lieselotte; Bracke, Nathalie; Wynendaele, Evelien; Joshi, Tanmayee; Tatke, Pratima; Taevernier, Lien

    2016-01-01

    Objective. To evaluate the gut mucosa and blood-brain barrier (BBB) pharmacokinetic permeability properties of the plant N-alkylamide pellitorine. Methods. Pure pellitorine and an Anacyclus pyrethrum extract were used to investigate the permeation of pellitorine through (1) a Caco-2 cell monolayer, (2) the rat gut after oral administration, and (3) the BBB in mice after intravenous and intracerebroventricular administration. A validated bioanalytical UPLC-MS2 method was used to quantify pellitorine. Results. Pellitorine was able to cross the Caco-2 cell monolayer from the apical-to-basolateral and from the basolateral-to-apical side with apparent permeability coefficients between 0.6 · 10−5 and 4.8 · 10−5 cm/h and between 0.3 · 10−5 and 5.8 · 10−5 cm/h, respectively. In rats, a serum elimination rate constant of 0.3 h−1 was obtained. Intravenous injection of pellitorine in mice resulted in a rapid and high permeation of pellitorine through the BBB with a unidirectional influx rate constant of 153 μL/(g·min). In particular, 97% of pellitorine reached the brain tissue, while only 3% remained in the brain capillaries. An efflux transfer constant of 0.05 min−1 was obtained. Conclusion. Pellitorine shows a good gut permeation and rapidly permeates the BBB once in the blood, indicating a possible role in the treatment of central nervous system diseases. PMID:27493960

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

    PubMed

    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.

  17. Escherichia coli heat-stable toxin b impairs intestinal epithelial barrier function by altering tight junction proteins.

    PubMed

    Ngendahayo Mukiza, Clément; Dubreuil, J Daniel

    2013-08-01

    Escherichia coli heat-stable toxin b (STb) causes diarrhea in animals. STb binds to sulfatide, its receptor, and is then internalized. In the cytoplasm, through a cascade of events, STb triggers the opening of ion channels, allowing ion secretion and water loss and leading to diarrhea. Tight junctions (TJs) are well known for controlling paracellular traffic of ions and water by forming a physical intercellular barrier in epithelial cells, and some bacterial toxins are known to affect adversely TJs. The present study aimed at determining the effect of STb on TJs. T84 cells were treated for 24 h with purified STb and a nontoxic STb mutant (D30V). Transepithelial resistance (TER), paracellular flux marker, and confocal microscopy were used to analyze the effect of STb on TJs. Purified STb caused a significant reduction of TER parallel to an increase in paracellular permeability compared to the results seen in untreated cells or mutant D30V. The increased paracellular permeability was associated with a marked alteration of F-actin stress fibers. F-actin filament dissolution and condensation were accompanied by redistribution and/or fragmentation of ZO-1, claudin-1, and occludin. These changes were also observed following treatment of T84 cells with an 8-amino-acid peptide found in the STb sequence corresponding to a consensus sequence of Vibrio cholerae Zot toxin. These effects were not observed with a scrambled peptide or mutant D30V. Our findings indicate that STb induces epithelial barrier dysfunction through changes in TJ proteins that could contribute to diarrhea.

  18. Escherichia coli Heat-Stable Toxin b Impairs Intestinal Epithelial Barrier Function by Altering Tight Junction Proteins

    PubMed Central

    Ngendahayo Mukiza, Clément

    2013-01-01

    Escherichia coli heat-stable toxin b (STb) causes diarrhea in animals. STb binds to sulfatide, its receptor, and is then internalized. In the cytoplasm, through a cascade of events, STb triggers the opening of ion channels, allowing ion secretion and water loss and leading to diarrhea. Tight junctions (TJs) are well known for controlling paracellular traffic of ions and water by forming a physical intercellular barrier in epithelial cells, and some bacterial toxins are known to affect adversely TJs. The present study aimed at determining the effect of STb on TJs. T84 cells were treated for 24 h with purified STb and a nontoxic STb mutant (D30V). Transepithelial resistance (TER), paracellular flux marker, and confocal microscopy were used to analyze the effect of STb on TJs. Purified STb caused a significant reduction of TER parallel to an increase in paracellular permeability compared to the results seen in untreated cells or mutant D30V. The increased paracellular permeability was associated with a marked alteration of F-actin stress fibers. F-actin filament dissolution and condensation were accompanied by redistribution and/or fragmentation of ZO-1, claudin-1, and occludin. These changes were also observed following treatment of T84 cells with an 8-amino-acid peptide found in the STb sequence corresponding to a consensus sequence of Vibrio cholerae Zot toxin. These effects were not observed with a scrambled peptide or mutant D30V. Our findings indicate that STb induces epithelial barrier dysfunction through changes in TJ proteins that could contribute to diarrhea. PMID:23716609

  19. Salmosan, a β-galactomannan-rich product, in combination with Lactobacillus plantarum contributes to restore intestinal epithelial barrier function by modulation of cytokine production.

    PubMed

    Brufau, M Teresa; Campo-Sabariz, Joan; Carné, Sergi; Ferrer, Ruth; Martín-Venegas, Raquel

    2017-03-01

    Mannan-oligosaccharides (MOSs) are mannose-rich substrates with several intestinal health-promoting properties. The aim of this study was to investigate the potential capacity of Salmosan (S-βGM), a β-galactomannan-rich MOS product, to restore epithelial barrier function independently from its capacity to reduce bacterial invasion. In addition, the combination of S-βGM with the proven probiotic Lactobacillus plantarum (LP) was also tested. Paracellular permeability was assessed by transepithelial electrical resistance (TER) in co-cultures of Caco-2 cells and macrophages (differentiated from THP-1 cells) stimulated with LPS of Salmonella Enteritidis and in Caco-2 cell cultures stimulated with TNF-α in the absence or presence of 500 μg/ml S-βGM, LP (MOI 10) or a combination of both. In both culture models, TER was significantly reduced up to 25% by LPS or TNF-α stimulation, and the addition of S-βGM or LP alone did not modify TER, whereas the combination of both restored TER to values of nonstimulated cells. Under LPS stimulation, TNF-α production was significantly increased by 10-fold, whereas IL-10 and IL-6 levels were not modified. The combination of S-βGM and LP reduced TNF-α production to nonstimulated cell values and significantly increased IL-10 and IL-6 levels (5- and 7.5-fold, respectively). Moreover, S-βGM has the capacity to induce an increase of fivefold in LP growth. In conclusion, we have demonstrated that S-βGM in combination with LP protects epithelial barrier function by modulation of cytokine secretion, thus giving an additional value to this MOS as a potential symbiotic.

  20. Biomechanics of oral mucosa

    PubMed Central

    Chen, Junning; Ahmad, Rohana; Li, Wei; Swain, Michael; Li, Qing

    2015-01-01

    The prevalence of prosthodontic treatment has been well recognized, and the need is continuously increasing with the ageing population. While the oral mucosa plays a critical role in the treatment outcome, the associated biomechanics is not yet fully understood. Using the literature available, this paper provides a critical review on four aspects of mucosal biomechanics, including static, dynamic, volumetric and interactive responses, which are interpreted by its elasticity, viscosity/permeability, apparent Poisson's ratio and friction coefficient, respectively. Both empirical studies and numerical models are analysed and compared to gain anatomical and physiological insights. Furthermore, the clinical applications of such biomechanical knowledge on the mucosa are explored to address some critical concerns, including stimuli for tissue remodelling (interstitial hydrostatic pressure), pressure–pain thresholds, tissue displaceability and residual bone resorption. Through this review, the state of the art in mucosal biomechanics and their clinical implications are discussed for future research interests, including clinical applications, computational modelling, design optimization and prosthetic fabrication. PMID:26224566

  1. Bacteria-Derived Compatible Solutes Ectoine and 5α-Hydroxyectoine Act as Intestinal Barrier Stabilizers to Ameliorate Experimental Inflammatory Bowel Disease.

    PubMed

    Abdel-Aziz, Heba; Wadie, Walaa; Scherner, Olaf; Efferth, Thomas; Khayyal, Mohamed T

    2015-06-26

    Earlier studies showed that the compatible solute ectoine (1) given prophylactically before induction of colitis by 2,4,6-trinitrobenzenesulfonic acid (TNBS) in rats prevented histological changes induced in the colon and the associated rise in inflammatory mediators. This study was therefore conducted to investigate whether ectoine (1) and its 5α-hydroxy derivative (2) would also be effective in treating an already established condition. Two days after inducing colitis in rats by instilling TNBS/alcohol in the colon, animals were treated orally once daily for 1 week with either 1 or 2 (50, 100, 300 mg/kg). Twenty-four hours after the last drug administration rats were sacrificed. Ulcerative lesions and colon mass indices were reduced by 1 and 2 in a bell-shaped manner. Best results were obtained with 100 mg/kg ectoine (1) and 50 mg/kg 5α-hydroxyectoine (2). The solutes normalized the rise in myeloperoxidase, TNFα, and IL-1β induced by TNBS but did not affect levels of reduced glutathione or ICAM-1, while reducing the level of fecal calprotectin, an established marker for inflammatory bowel disease. The findings indicate that the naturally occurring compatible solutes ectoine (1) and 5α-hydroxyectoine (2) possess an optimum concentration that affords maximal intestinal barrier stabilization and could therefore prove useful for better management of human inflammatory bowel disease.

  2. In vitro prediction of human intestinal absorption and blood-brain barrier partitioning: development of a lipid analog for micellar liquid chromatography.

    PubMed

    De Vrieze, Mike; Janssens, Pieter; Szucs, Roman; Van der Eycken, Johan; Lynen, Frédéric

    2015-09-01

    Over the past decades, several in vitro methods have been tested for their ability to predict either human intestinal absorption (HIA) or penetration across the blood-brain barrier (BBB) of drugs. Micellar liquid chromatography (MLC) has been a successful approach for retention time measurements of drugs to establish models together with other molecular descriptors. Thus far, MLC approaches have only made use of commercial surfactants such as sodium dodecyl sulfate (SDS) and polyoxyethylene (23) lauryl ether (Brij35), which are not representative for the phospholipids present in human membranes. Miltefosine, a phosphocholine-based lipid, is presented here as an alternative surfactant for MLC measurements. By using the obtained retention factors and several computed descriptors for a set of 48 compounds, two models were constructed: one for the prediction of HIA and another for the prediction of penetration across the BBB expressed as log BB. All data were correlated to experimental HIA and log BB values, and the performance of the models was evaluated. Log BB prediction performed better than HIA prediction, although HIA prediction was also improved a lot (from 0.5530 to 0.7175) compared to in silico predicted HIA values.

  3. Functional Coupling of Human Microphysiology Systems: Intestine, Liver, Kidney Proximal Tubule, Blood-Brain Barrier and Skeletal Muscle

    PubMed Central

    Vernetti, Lawrence; Gough, Albert; Baetz, Nicholas; Blutt, Sarah; Broughman, James R.; Brown, Jacquelyn A.; Foulke-Abel, Jennifer; Hasan, Nesrin; In, Julie; Kelly, Edward; Kovbasnjuk, Olga; Repper, Jonathan; Senutovitch, Nina; Stabb, Janet; Yeung, Catherine; Zachos, Nick C.; Donowitz, Mark; Estes, Mary; Himmelfarb, Jonathan; Truskey, George; Wikswo, John P.; Taylor, D. Lansing

    2017-01-01

    Organ interactions resulting from drug, metabolite or xenobiotic transport between organs are key components of human metabolism that impact therapeutic action and toxic side effects. Preclinical animal testing often fails to predict adverse outcomes arising from sequential, multi-organ metabolism of drugs and xenobiotics. Human microphysiological systems (MPS) can model these interactions and are predicted to dramatically improve the efficiency of the drug development process. In this study, five human MPS models were evaluated for functional coupling, defined as the determination of organ interactions via an in vivo-like sequential, organ-to-organ transfer of media. MPS models representing the major absorption, metabolism and clearance organs (the jejunum, liver and kidney) were evaluated, along with skeletal muscle and neurovascular models. Three compounds were evaluated for organ-specific processing: terfenadine for pharmacokinetics (PK) and toxicity; trimethylamine (TMA) as a potentially toxic microbiome metabolite; and vitamin D3. We show that the organ-specific processing of these compounds was consistent with clinical data, and discovered that trimethylamine-N-oxide (TMAO) crosses the blood-brain barrier. These studies demonstrate the potential of human MPS for multi-organ toxicity and absorption, distribution, metabolism and excretion (ADME), provide guidance for physically coupling MPS, and offer an approach to coupling MPS with distinct media and perfusion requirements. PMID:28176881

  4. Vitamin A supplementation effects on intestinal barrier function, growth, total parasitic and specific Giardia spp. infections in Brazilian children: a prospective randomized, double-blind, placebo-controlled trial

    PubMed Central

    Lima, Aldo A. M.; Soares, Alberto M.; Lima, Noélia L.; Mota, Rosa M. S.; Maciel, Bruna L. L.; Kvalsund, Michelle P.; Barrett, Leah J.; Fitzgerald, Relana P.; Blaner, William S.; Guerrant, Richard L.

    2009-01-01

    Background This study evaluates the effects of retinol on intestinal barrier function, growth, total parasites and Giardia spp. infections in children in the Northeast of Brazil. Methods The study was a double-blind, randomized placebo-controlled trial (http://clinicaltrials.gov;Register#NCT00133406) involving 79children reiceved vitamin A 100,000 - 200,000 IU (n = 39) or placebo (n = 40) at enrollment, 4 and 8 months, followed for 36 months. Intestinal barrier function was evaluated using the lactulose:mannitol test. Stool lactoferrin was used as a marker for intestinal inflammation. Results The groups were similar with regard to age, sex, nutritional parameters (z-scores), serum retinol concentrations, proportion of lactoferrin positive stool samples, and intestinal barrier function. The lactulose:mannitol ratio did not change during the same time of follow-up (p>0.05). The proportion of lactoferrin positive samples evaluated at one month did not change between groups (p>0.05). Total intestinal parasitic specifically new infections were significantly lower in the vitamin A treatment compared to control group; these were accounted for entirely by significantly fewer new Giardia infections in the vitamin A treatment group. The cumulative z-scores for weight-for-length or height (WHZ), length or height-for-age z-scores (HAZ), and weight-for-age (WAZ) did not change significantly with vitamin A intervention for 36 months of follow-up. Conclusions These data showed that total parasitic infection and Giardia spp. infections were significantly lower in the vitamin A treatment group when compared to the placebo group, suggesting that vitamin A improves host defenses against Giardia infections. PMID:20038852

  5. Toll-like receptor 2 activation by β2→1-fructans protects barrier function of T84 human intestinal epithelial cells in a chain length-dependent manner.

    PubMed

    Vogt, Leonie M; Meyer, Diederick; Pullens, Gerdie; Faas, Marijke M; Venema, Koen; Ramasamy, Uttara; Schols, Henk A; de Vos, Paul

    2014-07-01

    Dietary fiber intake is associated with lower incidence and mortality from disease, but the underlying mechanisms of these protective effects are unclear. We hypothesized that β2→1-fructan dietary fibers confer protection on intestinal epithelial cell barrier function via Toll-like receptor 2 (TLR2), and we studied whether β2→1-fructan chain-length differences affect this process. T84 human intestinal epithelial cell monolayers were incubated with 4 β2→1-fructan formulations of different chain-length compositions and were stimulated with the proinflammatory phorbol 12-myristate 13-acetate (PMA). Transepithelial electrical resistance (TEER) was analyzed by electric cell substrate impedance sensing (ECIS) as a measure for tight junction-mediated barrier function. To confirm TLR2 involvement in barrier modulation by β2→1-fructans, ECIS experiments were repeated using TLR2 blocking antibody. After preincubation of T84 cells with short-chain β2→1-fructans, the decrease in TEER as induced by PMA (62.3 ± 5.2%, P < 0.001) was strongly attenuated (15.2 ± 8.8%, P < 0.01). However, when PMA was applied first, no effect on recovery was observed during addition of the fructans. By blocking TLR2 on the T84 cells, the protective effect of short-chain β2→1-fructans was substantially inhibited. Stimulation of human embryonic kidney human TLR2 reporter cells with β2→1-fructans induced activation of nuclear factor kappa-light-chain-enhancer of activated B cells, confirming that β2→1-fructans are specific ligands for TLR2. To conclude, β2→1-fructans exert time-dependent and chain length-dependent protective effects on the T84 intestinal epithelial cell barrier mediated via TLR2. These results suggest that TLR2 located on intestinal epithelial cells could be a target of β2→1-fructan-mediated health effects.

  6. [Intestinal-brain axis. Neuronal and immune-inflammatory mechanisms of brain and intestine pathology].

    PubMed

    Bondarenko, V M; Riabichenko, E V

    2013-01-01

    Mutually directed connections between intestine and brain are implemented by endocrine, neural and immune systems and nonspecific natural immunity. Intestine micro flora as an active participant of intestine-brain axis not only influences intestine functions but also stimulates the development of CNS in perinatal period and interacts with higher nervous centers causing depression and cognitive disorders in pathology. A special role belongs to intestine microglia. Apart from mechanic (protective) and trophic functions for intestine neurons, glia implements neurotransmitter, immunologic, barrier and motoric functions in the intestine. An interconnection between intestine barrier function and hematoencephalic barrier regulation exists. Chronic endotoxinemia as a result of intestine barrier dysfunction forms sustained inflammation state in periventricular zone of the brain with consequent destabilization of hematoencephalic barriers and spread oF inflammation to other parts of the brain resulting in neurodegradation development.

  7. Development of an advanced intestinal in vitro triple culture permeability model to study transport of nanoparticles.

    PubMed

    Schimpel, Christa; Teubl, Birgit; Absenger, Markus; Meindl, Claudia; Fröhlich, Eleonore; Leitinger, Gerd; Zimmer, Andreas; Roblegg, Eva

    2014-03-03

    Intestinal epithelial cell culture models, such as Caco-2 cells, are commonly used to assess absorption of drug molecules and transcytosis of nanoparticles across the intestinal mucosa. However, it is known that mucus strongly impacts nanoparticle mobility and that specialized M cells are involved in particulate uptake. Thus, to get a clear understanding of how nanoparticles interact with the intestinal mucosa, in vitro models are necessary that integrate the main cell types. This work aimed at developing an alternative in vitro permeability model based on a triple culture: Caco-2 cells, mucus-secreting goblet cells and M cells. Therefore, Caco-2 cells and mucus-secreting goblet cells were cocultured on Transwells and Raji B cells were added to stimulate differentiation of M cells. The in vitro triple culture model was characterized regarding confluence, integrity, differentiation/expression of M cells and cell surface architecture. Permeability of model drugs and of 50 and 200 nm polystyrene nanoparticles was studied. Data from the in vitro model were compared with ex vivo permeability results (Ussing chambers and porcine intestine) and correlated well. Nanoparticle uptake was size-dependent and strongly impacted by the mucus layer. Moreover, nanoparticle permeability studies clearly demonstrated that particles were capable of penetrating the intestinal barrier mainly via specialized M cells. It can be concluded that goblet cells and M cells strongly impact nanoparticle uptake in the intestine and should thus be integrated in an in vitro permeability model. The presented model will be an efficient tool to study intestinal transcellular uptake of particulate systems.

  8. Loss of intestinal O-glycans promotes spontaneous duodenal tumors.

    PubMed

    Gao, Nan; Bergstrom, Kirk; Fu, Jianxin; Xie, Biao; Chen, Weichang; Xia, Lijun

    2016-07-01

    Mucin-type O-glycans, primarily core 1- and core 3-derived O-glycans, are the major mucus barrier components throughout the gastrointestinal tract. Previous reports identified the biological role of O-glycans in the stomach and colon. However, the biological function of O-glycans in the small intestine remains unknown. Using mice lacking intestinal core 1- and core 3-derived O-glycans [intestinal epithelial cell C1galt1(-/-);C3GnT(-/-) or double knockout (DKO)], we found that loss of O-glycans predisposes DKO mice to spontaneous duodenal tumorigenesis by ∼1 yr of age. Tumor incidence did not increase with age; however, tumors advanced in aggressiveness by 20 mo. O-glycan deficiency was associated with reduced luminal mucus in DKO mice before tumor development. Altered intestinal epithelial homeostasis with enhanced baseline crypt proliferation characterizes these phenotypes as assayed by Ki67 staining. In addition, fluorescence in situ hybridization analysis reveals a significantly lower bacterial burden in the duodenum compared with the large intestine. This phenotype is not reduced with antibiotic treatment, implying O-glycosylation defects, rather than bacterial-induced inflammation, which causes spontaneous duodenal tumorigenesis. Moreover, inflammatory responses in DKO duodenal mucosa are mild as assayed with histology, quantitative PCR for inflammation-associated cytokines, and immunostaining for immune cells. Importantly, inducible deletion of intestinal O-glycans in adult mice leads to analogous spontaneous duodenal tumors, although with higher incidence and heightened severity compared with mice with O-glycans constitutive deletion. In conclusion, these studies reveal O-glycans within the small intestine are critical determinants of duodenal cancer risk. Future studies will provide insights into the pathogenesis in the general population and those at risk for this rare but deadly cancer.

  9. 1,25-Dihydroxyvitamin D3 preserves intestinal epithelial barrier function from TNF-α induced injury via suppression of NF-kB p65 mediated MLCK-P-MLC signaling pathway.

    PubMed

    Chen, Shanwen; Zhu, Jing; Chen, Guowei; Zuo, Shuai; Zhang, Junling; Chen, Ziyi; Wang, Xin; Li, Junxia; Liu, Yucun; Wang, Pengyuan

    2015-05-08

    Substantial studies have demonstrated the protective effect of 1,25-Dihydroxyvitamin D3 (1,25(OH)2D3) on intestinal barrier function, but the mechanisms are not fully illustrated. In this study, the effect of 1,25(OH)2D3 on TNF-α induced barrier dysfunction was further investigated in Caco-2 cell monolayers. The barrier function of Caco-2 monolayers was evaluated by measuring trans-epithelial electrical resistance (TEER) and FITC-Dextran 40,000 Da (FD-40) trans-membrane flux. ZO-1 and Occludin were chosen as markers of the localization of tight junction (TJ) proteins for immunofluorescence. The expression of MLCK and phosphorylation level of myosin light chain (MLC) were measured by immunoblotting. The activation of NF-kB p65 was analyzed by EMSA and immunofluorescence. The results suggest that 1,25(OH)2D3 preserves intestinal epithelial barrier function from TNF-α induced injury via suppression of NF-kB p65 mediated activation of MLCK-P-MLC signaling pathway.

  10. The use of polyion complex micelles to enhance the oral delivery of salmon calcitonin and transport mechanism across the intestinal epithelial barrier.

    PubMed

    Li, Na; Li, Xin-Ru; Zhou, Yan-Xia; Li, Wen-Jing; Zhao, Yong; Ma, Shu-Jin; Li, Jin-Wen; Gao, Ya-Jie; Liu, Yan; Wang, Xing-Lin; Yin, Dong-Dong

    2012-12-01

    The objective of the present study was to demonstrate the effect of polyanionic copolymer mPEG-grafted-alginic acid (mPEG-g-AA)-based polyion complex (PIC) micelles on enhancing the oral absorption of salmon calcitonin (sCT) in vivo and in vitro and identify the transepithelial transport mechanism of PIC micelles across the intestinal barrier. mPEG-g-AA was first successfully synthesized and characterized in cytotoxicity. The PIC micelles were approximately of 72 nm in diameter with a narrow distribution. The extremely significant enhancement of hypocalcemia efficacy of sCT-loaded PIC micelles in rats was evidenced by intraduodenal administration in comparison with sCT solution. The presence of mPEG-grafted-chitosan in PIC micelles had no favorable effect on this action in the referred content. In the Caco-2 transport studies, PIC micelles could significantly increase the permeability of sCT across Caco-2 monolayers without significantly affecting transepithelial electrical resistance values during the transport study. No evident alterations in the F-actin cytoskeleton were detected by confocal microscope observation following treatment of the cell monolayers with PIC micelles, which further certified the incapacity of PIC micelles to open the intercellular tight junctions. In addition, TEM observations showed that the intact PIC micelles were transported across the everted gut sac. These suggested that the transport of PIC micelles across Caco-2 cell monolayers involve a predominant transcytosis mechanism via endocytosis rather than paracellular pathway. Furthermore, PIC micelles were localized in both the cytoplasm and the nuclei observed by CLSM. Therefore, PIC micelles might be a potentially applicable tool for enhancing the oral absorption of cationic peptide and protein drugs.

  11. Protection by Short-Chain Fatty Acids against 1-β-d-Arabinofuranosylcytosine-Induced Intestinal Lesions in Germfree Mice†

    PubMed Central

    Ramos, Mariana Gontijo; Bambirra, Eduardo Alves; Nicoli, Jacques Robert; Cara, Denise Carmona; Vieira, Enio Cardillo; Alvarez-Leite, Jacqueline

    1999-01-01

    In germfree mice, the administration of short-chain fatty acids (SCFA) protected the intestinal mucosa from damage produced by 1-β-d-arabinofuranosylcytosine (Ara-C). Animals receiving SCFA and Ara-C had intestinal morphologies closer to normal than the control animals, which had severe intestinal lesions. We concluded that orally administrated SCFA reduce intestinal lesions, improving the mucosa pattern of the small intestine and colon. PMID:10103207

  12. [Chronic gastritis and intestinal metaplasia].

    PubMed

    Castillo, T; Navarrete, J; Celestina, A

    1989-01-01

    Much has been written about gastric mucosae behavior and the occurrence of intestinal metaplasia. The aim of this paper is to learn something more about these matters in peruvian population. We selected 100 patients with endoscopically no localized lesions between 30 to 70 years of age. We took 8 samples of gastric mucosae in each patient which were carefully examined for the presence of inflammatory changes, settle the line type between antral and fundic mucosae and the frequency of intestinal metaplasia finding. The results showed disagreement between endoscopic and histological findings, so we conclude it is better to diagnose chronic gastritis on the basis of histological parameters. The line between antral and fundic mucosae was of the close type one found in 87% of all cases and it advanced proximally with increasing age. Intestinal metaplasia was present in 46% of the whole number of patients and the rate of occurrence increased in 50% over 50 years age. These findings will let us compare future investigations of gastric mucosae behavior with localized benign or malign lesions.

  13. Epithelial-mesenchymal interactions as a working concept for oral mucosa regeneration.

    PubMed

    Liu, Jiarong; Mao, Jeremy J; Chen, Lili

    2011-02-01

    Oral mucosa consists of two tissue layers, the superficial epithelium and the underlying lamina propria. Together, oral mucosa functions as a barrier against exogenous substances and pathogens. In development, interactions of stem/progenitor cells of the epithelium and mesenchyme are crucial to the morphogenesis of oral mucosa. Previous work in oral mucosa regeneration has yielded important clues for several meritorious proof-of-concept approaches. Tissue engineering offers a broad array of novel tools for oral mucosa regeneration with reduced donor site trauma and accelerated clinical translation. However, the developmental concept of epithelial-mesenchymal interactions (EMIs) is rarely considered in oral mucosa regeneration. EMIs in postnatal oral mucosa regeneration likely will not be a simple recapitulation of prenatal oral mucosa development. Biomaterial scaffolds play an indispensible role for oral mucosa regeneration and should provide a conducive environment for pivotal EMIs. Autocrine and paracrine factors, either exogenously delivered or innately produced, have rarely been and should be harnessed to promote oral mucosa regeneration. This review focuses on a working concept of epithelial and mesenchymal interactions in oral mucosa regeneration.

  14. Mucosal Barrier in Ulcerative Colitis and Crohn's Disease

    PubMed Central

    Dorofeyev, A. E.; Vasilenko, I. V.; Rassokhina, O. A.; Kondratiuk, R. B.

    2013-01-01

    Background. The mucus layer in the gastrointestinal tract plays important role in host innate defense, regulation of secretion, and absorption processes, maintaining colonization resistance, which composes the integrity of protective mucus barrier in the large intestine. Investigations of mucin expression in the colon mucosa can improve the understanding of protective function of mucosal barrier in ulcerative colitis (UC) and Crohn's disease (CD). Materials and Methods. 77 patients with UC and CD were examined. Histological analysis of colon mucosa was done by standard method (haematoxylin-eosin, alcian blue at pH 1.0 and 2.5 to determine sulfated and nonsulfated glycosaminoglycans and glycoproteins, and goblet cells). To characterize the mucus production the PAS-reaction was performed. Immunohistochemistry was performed using monoclonal mouse antibodies raised against MUC2, MUC3, MUC4, and TFF3 (USBiological, USA). Results. The moderate expression of MUC2 and MUC3 (50.0% and 32.1%, P = 0.03) and high expression of MUC4 and TFF3 in the colon mucosa were observed in all patients with CD. The intensive labeling of MUC4 and TFF3 occurred more often (42.9% and 57.1%, P = 0.03) in patients with CD. The level of expression of secretory MUC2 and transmembrane MUC3 and MUC4 in all patients with UC was low, up to its complete absence (59.2% and 53.1% cases, P = 0.05). TFF3 expression had high and medium staining intensity in patients with UC. Conclusions. Different types of mucins synthesis, secretion, and expression were found in patients with UC and CD. The expression of mucin MUC2, MUC3, MUC4, and TFF3 correlated with the activity of disease and the extent of the inflammatory process in the large intestine. The most pronounced alteration of mucins expression was observed in patients with severe UC and CD. PMID:23737764

  15. Host-compound foraging by intestinal microbiota revealed by single-cell stable isotope probing.

    PubMed

    Berry, David; Stecher, Bärbel; Schintlmeister, Arno; Reichert, Jochen; Brugiroux, Sandrine; Wild, Birgit; Wanek, Wolfgang; Richter, Andreas; Rauch, Isabella; Decker, Thomas; Loy, Alexander; Wagner, Michael

    2013-03-19

    The animal and human intestinal mucosa secretes an assortment of compounds to establish a physical barrier between the host tissue and intestinal contents, a separation that is vital for health. Some pathogenic microorganisms as well as members of the commensal intestinal microbiota have been shown to be able to break down these secreted compounds. Our understanding of host-compound degradation by the commensal microbiota has been limited to knowledge about simplified model systems because of the difficulty in studying the complex intestinal ecosystem in vivo. In this study, we introduce an approach that overcomes previous technical limitations and allows us to observe which microbial cells in the intestine use host-derived compounds. We added stable isotope-labeled threonine i.v. to mice and combined fluorescence in situ hybridization with high-resolution secondary ion mass spectrometry imaging to characterize utilization of host proteins by individual bacterial cells. We show that two bacterial species, Bacteroides acidifaciens and Akkermansia muciniphila, are important host-protein foragers in vivo. Using gnotobiotic mice we show that microbiota composition determines the magnitude and pattern of foraging by these organisms, demonstrating that a complex microbiota is necessary in order for this niche to be fully exploited. These results underscore the importance of in vivo studies of intestinal microbiota, and the approach presented in this study will be a powerful tool to address many other key questions in animal and human microbiome research.

  16. Ulcerative colitis as a polymicrobial infection characterized by sustained broken mucus barrier

    PubMed Central

    Chen, Shui-Jiao; Liu, Xiao-Wei; Liu, Jian-Ping; Yang, Xi-Yan; Lu, Fang-Gen

    2014-01-01

    To reduce medication for patients with ulcerative colitis (UC), we need to establish the etiology of UC. The intestinal microbiota of patients with inflammatory bowel disease (IBD) has been shown to differ from that of healthy controls and abundant data indicate that it changes in both composition and localization. Small intestinal bacterial overgrowth is significantly higher in IBD patients compared with controls. Probiotics have been investigated for their capacity to reduce the severity of UC. The luminal surfaces of the gastrointestinal tract are covered by a mucus layer. This normally acts as a barrier that does not allow bacteria to reach the epithelial cells and thus limits the direct contact between the host and the bacteria. The mucus layer in the colon comprises an inner layer that is firmly adherent to the intestinal mucosa, and an outer layer that can be washed off with minimal rinsing. Some bacteria can dissolve the protective inner mucus layer. Defects in renewal and formation of the inner mucus layer allow bacteria to reach the epithelium and have implications for the causes of colitis. In this review, important elements of UC pathology are thought to be the intestinal bacteria, gut mucus, and the mucosa-associated immune system. PMID:25071341

  17. Outer Membrane Vesicles and Soluble Factors Released by Probiotic Escherichia coli Nissle 1917 and Commensal ECOR63 Enhance Barrier Function by Regulating Expression of Tight Junction Proteins in Intestinal Epithelial Cells.

    PubMed

    Alvarez, Carina-Shianya; Badia, Josefa; Bosch, Manel; Giménez, Rosa; Baldomà, Laura

    2016-01-01

    The gastrointestinal epithelial layer forms a physical and biochemical barrier that maintains the segregation between host and intestinal microbiota. The integrity of this barrier is critical in maintaining homeostasis in the body and its dysfunction is linked to a variety of illnesses, especially inflammatory bowel disease. Gut microbes, and particularly probiotic bacteria, modulate the barrier integrity by reducing gut permeability and reinforcing tight junctions. Probiotic Escherichia coli Nissle 1917 (EcN) is a good colonizer of the human gut with proven therapeutic efficacy in the remission of ulcerative colitis in humans. EcN positively modulates the intestinal epithelial barrier through upregulation and redistribution of the tight junction proteins ZO-1, ZO-2 and claudin-14. Upregulation of claudin-14 has been attributed to the secreted protein TcpC. Whether regulation of ZO-1 and ZO-2 is mediated by EcN secreted factors remains unknown. The aim of this study was to explore whether outer membrane vesicles (OMVs) released by EcN strengthen the epithelial barrier. This study includes other E. coli strains of human intestinal origin that contain the tcpC gene, such as ECOR63. Cell-free supernatants collected from the wild-type strains and from the derived tcpC mutants were fractionated into isolated OMVs and soluble secreted factors. The impact of these extracellular fractions on the epithelial barrier was evaluated by measuring transepithelial resistance and expression of several tight junction proteins in T-84 and Caco-2 polarized monolayers. Our results show that the strengthening activity of EcN and ECOR63 does not exclusively depend on TcpC. Both OMVs and soluble factors secreted by these strains promote upregulation of ZO-1 and claudin-14, and down-regulation of claudin-2. The OMVs-mediated effects are TcpC-independent. Soluble secreted TcpC contributes to the upregulation of ZO-1 and claudin-14, but this protein has no effect on the transcriptional

  18. Outer Membrane Vesicles and Soluble Factors Released by Probiotic Escherichia coli Nissle 1917 and Commensal ECOR63 Enhance Barrier Function by Regulating Expression of Tight Junction Proteins in Intestinal Epithelial Cells

    PubMed Central

    Alvarez, Carina-Shianya; Badia, Josefa; Bosch, Manel; Giménez, Rosa; Baldomà, Laura

    2016-01-01

    The gastrointestinal epithelial layer forms a physical and biochemical barrier that maintains the segregation between host and intestinal microbiota. The integrity of this barrier is critical in maintaining homeostasis in the body and its dysfunction is linked to a variety of illnesses, especially inflammatory bowel disease. Gut microbes, and particularly probiotic bacteria, modulate the barrier integrity by reducing gut permeability and reinforcing tight junctions. Probiotic Escherichia coli Nissle 1917 (EcN) is a good colonizer of the human gut with proven therapeutic efficacy in the remission of ulcerative colitis in humans. EcN positively modulates the intestinal epithelial barrier through upregulation and redistribution of the tight junction proteins ZO-1, ZO-2 and claudin-14. Upregulation of claudin-14 has been attributed to the secreted protein TcpC. Whether regulation of ZO-1 and ZO-2 is mediated by EcN secreted factors remains unknown. The aim of this study was to explore whether outer membrane vesicles (OMVs) released by EcN strengthen the epithelial barrier. This study includes other E. coli strains of human intestinal origin that contain the tcpC gene, such as ECOR63. Cell-free supernatants collected from the wild-type strains and from the derived tcpC mutants were fractionated into isolated OMVs and soluble secreted factors. The impact of these extracellular fractions on the epithelial barrier was evaluated by measuring transepithelial resistance and expression of several tight junction proteins in T-84 and Caco-2 polarized monolayers. Our results show that the strengthening activity of EcN and ECOR63 does not exclusively depend on TcpC. Both OMVs and soluble factors secreted by these strains promote upregulation of ZO-1 and claudin-14, and down-regulation of claudin-2. The OMVs-mediated effects are TcpC-independent. Soluble secreted TcpC contributes to the upregulation of ZO-1 and claudin-14, but this protein has no effect on the transcriptional

  19. Hyalinosis cutis et mucosae.

    PubMed

    Vago, Bernadette; Hausser, Ingrid; Hennies, Hans Christian; Enk, Alexander; Jappe, Uta

    2007-05-01

    Hyalinosis cutis et mucosae is a rare autosomal recessive disorder which is characterized by deposition of hyaline material around the basement membrane of the skin and mucous membranes. Typical clinical symptoms are hoarseness, infiltration of the mucous membranes and papular verrucous skin changes. Mutations within the extracellular matrix protein gene (ECM-1) are the underlying defect. We report on a 24-year-old man, who had first been seen in our department at the age of seven and had undergone the necessary diagnostic procedures and who revisited 17 years later with hoarseness and extensive verrucous skin changes at elbows and knees which were removed by excision. A new mutation of the ECM1 gene was identified.

  20. Permeability Profiles and Intestinal Toxicity Assessment of Hydrochlorothiazide and Its Inclusion Complex with β-Cyclodextrin Loaded into Chitosan Nanoparticles.

    PubMed

    Onnainty, R; Schenfeld, E M; Petiti, J P; Longhi, M R; Torres, A; Quevedo, M A; Granero, G E

    2016-11-07

    Here, a novel drug delivery system was developed for the hydrochlorothiazide (HCT):β-cyclodextrin (βCD) inclusion complex loaded into chitosan (CS) nanoparticles (NPs) [CS/HCT:βCD NPs]. It was found, for the first time, that exposure of the intestinal mucosa to free HCT resulted in an increased and abnormal intestinal permeability associated with several injuries to the intestinal epithelium. Nevertheless, the HCT delivery system obtained ameliorated the damage of the intestinal epithelium induced by HCT. Furthermore, we found that the corresponding permeability profiles for both the free HCT and the CS/HCT:βCD NPs were exponential and lineal, respectively. We propose that the increased intestinal uptake and severe tissue injury of HCT to the intestinal epithelium could be directly related to possible effects of this drug on the ionoregulatory Na(+/)K(+)-ATPase channel. Thus, it is postulated that the CS/HCT:βCD NPs may increase the gastrointestinal retention of the HCT, which would provide increased adherence to the mucus barrier that lines the intestinal epithelium; consequently, this would act as a slow HCT release delivery system and maintain lower drug levels of luminal gut in comparison with the administration of free HCT, leading to less severe local injury.

  1. Interleukin-10 Enhances the Intestinal Epithelial Barrier in the Presence of Corticosteroids through p38 MAPK Activity in Caco-2 Monolayers: A Possible Mechanism for Steroid Responsiveness in Ulcerative Colitis

    PubMed Central

    Lorén, Violeta; Cabré, Eduard; Ojanguren, Isabel; Domènech, Eugeni; Pedrosa, Elisabet; García-Jaraquemada, Arce; Mañosa, Miriam; Manyé, Josep

    2015-01-01

    Glucocorticosteroids are the first line therapy for moderate-severe flare-ups of ulcerative colitis. Despite that, up to 60% of patients do not respond adequately to steroid treatment. Previously, we reported that low IL-10 mRNA levels in intestine are associated with a poor response to glucocorticoids in active Crohn’s disease. Here, we test whether IL-10 can favour the response to glucocorticoids by improving the TNFα-induced intestinal barrier damage (assessed by transepithelial electrical resistance) in Caco-2 monolayers, and their possible implications on glucocorticoid responsiveness in active ulcerative colitis. We show that the association of IL-10 and glucocorticoids improves the integrity of TNFα-treated Caco-2 cells and that p38 MAPK plays a key role. In vitro, IL-10 facilitates the nuclear translocation of p38 MAPK-phosphorylated thereby modulating glucocorticoids-receptor-α, IL-10-receptor-α and desmoglein-2 expression. In glucocorticoids-refractory patients, p38 MAPK phosphorylation and membrane desmoglein-2 expression are reduced in colonic epithelial cells. These results suggest that p38 MAPK-mediated synergism between IL-10 and glucocorticoids improves desmosome straightness contributing to the recovery of intestinal epithelium and reducing luminal antigens contact with lamina propria in ulcerative colitis. This study highlights the link between the intestinal epithelium in glucocorticoids-response in ulcerative colitis. PMID:26090671

  2. Interleukin-10 Enhances the Intestinal Epithelial Barrier in the Presence of Corticosteroids through p38 MAPK Activity in Caco-2 Monolayers: A Possible Mechanism for Steroid Responsiveness in Ulcerative Colitis.

    PubMed

    Lorén, Violeta; Cabré, Eduard; Ojanguren, Isabel; Domènech, Eugeni; Pedrosa, Elisabet; García-Jaraquemada, Arce; Mañosa, Miriam; Manyé, Josep

    2015-01-01

    Glucocorticosteroids are the first line therapy for moderate-severe flare-ups of ulcerative colitis. Despite that, up to 60% of patients do not respond adequately to steroid treatment. Previously, we reported that low IL-10 mRNA levels in intestine are associated with a poor response to glucocorticoids in active Crohn's disease. Here, we test whether IL-10 can favour the response to glucocorticoids by improving the TNFα-induced intestinal barrier damage (assessed by transepithelial electrical resistance) in Caco-2 monolayers, and their possible implications on glucocorticoid responsiveness in active ulcerative colitis. We show that the association of IL-10 and glucocorticoids improves the integrity of TNFα-treated Caco-2 cells and that p38 MAPK plays a key role. In vitro, IL-10 facilitates the nuclear translocation of p38 MAPK-phosphorylated thereby modulating glucocorticoids-receptor-α, IL-10-receptor-α and desmoglein-2 expression. In glucocorticoids-refractory patients, p38 MAPK phosphorylation and membrane desmoglein-2 expression are reduced in colonic epithelial cells. These results suggest that p38 MAPK-mediated synergism between IL-10 and glucocorticoids improves desmosome straightness contributing to the recovery of intestinal epithelium and reducing luminal antigens contact with lamina propria in ulcerative colitis. This study highlights the link between the intestinal epithelium in glucocorticoids-response in ulcerative colitis.

  3. Effect of a Semi-Purified Oligosaccharide-Enriched Fraction from Caprine Milk on Barrier Integrity and Mucin Production of Co-Culture Models of the Small and Large Intestinal Epithelium

    PubMed Central

    Barnett, Alicia M.; Roy, Nicole C.; McNabb, Warren C.; Cookson, Adrian L.

    2016-01-01

    Caprine milk contains the highest amount of oligosaccharides among domestic animals, which are structurally similar to human milk oligosaccharides (HMOs). This suggests caprine milk oligosaccharides may offer similar protective and developmental effects to that of HMOs. However, to date, studies using oligosaccharides from caprine milk have been limited. Thus, this study aimed to examine the impact of a caprine milk oligosaccharide-enriched fraction (CMOF) on barrier function of epithelial cell co-cultures of absorptive enterocytes (Caco-2 cells) and mucus-secreting goblet cells (HT29-MTX cells), that more closely simulate the cell proportions found in the small (90:10) and large intestine (75:25). Treatment of epithelial co-cultures with 0.4, 1.0, 2.0 and 4.0 mg/mL of CMOF was shown to have no effect on metabolic activity but did enhance cell epithelial barrier integrity as measured by trans-epithelial electrical resistance (TEER), in a dose-dependent manner. The CMOF at the maximum concentration tested (4.0 mg/mL) enhanced TEER, mucin gene expression and mucin protein abundance of epithelial co-cultures, all of which are essential components of intestinal barrier function. PMID:27164134

  4. Effects of Lactobacillus acidophilus dietary supplementation on the performance, intestinal barrier function, rectal microflora and serum immune function in weaned piglets challenged with Escherichia coli lipopolysaccharide.

    PubMed

    Qiao, Jiayun; Li, Haihua; Wang, Zhixiang; Wang, Wenjie

    2015-04-01

    This study was conducted with a lipopolysaccharide (LPS)-challenged piglet model to determine the effects of diets containing Lactobacillus acidophilus on the performance, intestinal barrier function, rectal microflora and serum immune function. A total of 150 piglets (initial body weight (BW) 7.53 ± 0.21 kg) were allotted to one of the following diets, including a basal diet, a basal diet supplemented with 250 mg/kg Flavomycin, or basal diet plus 0.05, 0.1 or 0.2 % L. acidophilus. On day 28 of the trial, the pigs were given an intraperitoneal injection of LPS (200 μg/kg body weight) followed by blood collection 3 h later. Diets with either antibiotics, 0.1 or 0.2 % Lactobacillus increased (P < 0.05) the final BW and decreased (P < 0.05) feed gain ratio (F/G) compared with the control group. Pigs fed diets containing antibiotic or Lactobacillus had greater average daily gain (ADG) (P < 0.05) than pigs fed the control diet. The rectal content Lactobacillus counts for pigs fed diet containing Lactobacillus were significant higher (P < 0.01) than those fed antibiotic or control diet. Feeding the Lactobacillus diets decreased the Escherichia coli counts of rectal content (P < 0.01). Pigs fed diets containing 0.1 or 0.2 % Lactobacillus decreased serum DAO activity (P < 0.05) compared with pigs fed the control diet. Serum IL-10 concentration was enhanced in pigs fed the diet with Lactobacillus compared to pigs fed the control diet and antibiotic diet. Feeding a diet with Lactobacillus reduced (P < 0.05) IFN-γ concentration compared to the control diet. Inclusion of Lactobacillus in diets fed to pigs reduced TNF-α concentration compared with pigs fed no Lactobacillus (P < 0.05). These results indicate that feeding with L. acidophilus improved growth performance and protected against LPS-induced inflammatory status.

  5. Proteome Analysis of Rheumatoid Arthritis Gut Mucosa.

    PubMed

    Bennike, Tue Bjerg; Ellingsen, Torkell; Glerup, Henning; Bonderup, Ole Kristian; Carlsen, Thomas Gelsing; Meyer, Michael Kruse; Bøgsted, Martin; Christiansen, Gunna; Birkelund, Svend; Andersen, Vibeke; Stensballe, Allan

    2017-01-06

    Rheumatoid arthritis (RA) is an inflammatory joint disease leading to cartilage damage and ultimately impaired joint function. To gain new insight into the systemic immune manifestations of RA, we characterized the colon mucosa proteome from 11 RA-patients and 10 healthy controls. The biopsies were extracted by colonoscopy and analyzed by label-free quantitative proteomics, enabling the quantitation of 5366 proteins. The abundance of dihydrofolate reductase (DHFR) was statistically significantly increased in RA-patient biopsies compared with controls and correlated with the administered dosage of methotrexate (MTX), the most frequently prescribed immunosuppressive drug for RA. Additionally, our data suggest that treatment with Leflunomide, a common alternative to MTX, increases DHFR. The findings were supported by immunohistochemistry with confocal microscopy, which furthermore demonstrated that DHFR was located in the cytosol of the intestinal epithelial and interstitial cells. Finally, we identified 223 citrullinated peptides from 121 proteins. Three of the peptides were unique to RA. The list of citrullinated proteins was enriched in extracellular and membrane proteins and included known targets of anticitrullinated protein antibodies (ACPAs). Our findings support that the colon mucosa could trigger the production of ACPAs, which could contribute to the onset of RA. The MS data have been deposited to ProteomeXchange with identifiers PXD001608 and PXD003082.

  6. [The colorectal adenoma-carcinoma sequence: the limits between polypectomy and intestinal resection].

    PubMed

    Giacomelli, L; Brescia, A; Pulcini, A; Finizio, R; Fabrizio, G; Granai, A V; Messinetti, S

    1993-01-01

    According to a clinic case, the authors pointed out the role of histological diagnosis in the therapeutic approach of large intestinal adenomas. In order to identify those lesions which can metastasize, having exceeded the muscularis mucosae and having invaded the submucosa, rigorous histological standards must be performed. Intestinal resection versus polypectomy is determined only according to the involvement or not of the muscularis mucosae.

  7. Improvement of the intestinal membrane permeability of low molecular weight heparin by complexation with stem bromelain.

    PubMed

    Grabovac, V; Bernkop-Schnürch, A

    2006-12-01

    The aim of this study was to investigate the influence of the proteolytic enzyme bromelain on the permeation of heparin across the gastrointestinal epithelial barrier. Stability of the complex and effect of heparin on the enzymatic activity of bromelain was analysed photometrically by measuring bromelain enzymatic activity in complex with the heparin. In vitro permeation studies were performed with Caco-2 cell monolayer and rat small intestinal mucosa in Ussing-type chambers, respectively. Results revealed that enzymatic activity of bromelain remained uninfluenced by the immobilization of heparin on it. Transport studies across Caco-2 cell monolayer and rat small intestine showed that the permeation of heparin could be significantly increased in presence of bromelain. In the study with Caco-2 cells, the most effective molar ratio of bromelain to heparin was 2:1, leading to 6.7-fold improvement in uptake, whereas the molar ratio 1:1 showed the highest permeation enhancing effect in the study on intestinal mucosa. This study provides evidence that heparin and bromelain form stable complexes leading to a significantly improved uptake of heparin.

  8. "Green" synthesized and coated nanaosilver alters the membrance permeability of barrier (intestinal, brain, endothelial) cells and stimulates oxidative stress pathways in neurons.

    EPA Science Inventory

    Nanosilver's (nanoAg) use in medical applications and consumer products is increasing. Because of this, its "green" synthesis and surface modification with beneficial coatings are desirable. Given nanoAg's potential exposure routes (e.g., dermal, intestin...

  9. Intestinal first-pass metabolism by cytochrome p450 and not p-glycoprotein is the major barrier to amprenavir absorption.

    PubMed

    Dufek, Matthew B; Bridges, Arlene S; Thakker, Dhiren R

    2013-09-01

    Recent studies showed that P-glycoprotein (P-gp) increases the portal bioavailability (FG) of loperamide by sparing its intestinal first-pass metabolism. Loperamide is a drug whose oral absorption is strongly attenuated by intestinal P-gp-mediated efflux and first-pass metabolism by cytochrome P450 3A (CYP3A). Here the effect of the interplay of P-gp and Cyp3a in modulating intestinal first-pass metabolism and absorption was investigated for another Cyp3a/P-gp dual substrate amprenavir, which is less efficiently effluxed by P-gp than loperamide. After oral administration of amprenavir, the portal concentrations and FG of amprenavir were approximately equal in P-gp competent and P-gp deficient mice. Mechanistic studies on the effect of P-gp on Cyp3a-mediated metabolism of amprenavir using intestinal tissue from P-gp competent and P-gp deficient mice (Ussing-type diffusion chamber) revealed that P-gp-mediated efflux caused only a slight reduction of oxidative metabolism of amprenavir. Studies in which portal concentrations and FG were measured in P-gp competent and P-gp deficient mice whose cytochrome P450 (P450) enzymes were either intact or inactivated showed that intestinal first-pass metabolism attenuates the oral absorption of amprenavir by approximately 10-fold, whereas P-gp efflux has a relatively small effect (approximately 2-fold) in attenuating the intestinal absorption. Cumulatively, these studies demonstrate that P-gp has little influence on the intestinal first-pass metabolism and FG of amprenavir and that intestinal P450-mediated metabolism plays the dominant role in attenuating the oral absorption of this drug.

  10. Fish oil enhances intestinal integrity and inhibits TLR4 and NOD2 signaling pathways in weaned pigs after LPS challenge.

    PubMed

    Liu, Yulan; Chen, Feng; Odle, Jack; Lin, Xi; Jacobi, Sheila K; Zhu, Huiling; Wu, Zhifeng; Hou, Yongqing

    2012-11-01

    Long-chain (n-3) PUFA exert beneficial effects on inflammatory bowel diseases in animal models and clinical trials. In addition, pattern recognition receptors such as toll-like receptors (TLR) and nucleotide-binding oligomerization domain proteins (NOD) play a critical role in intestinal inflammation. We hypothesized that fish oil could alleviate Escherichia coli LPS-induced intestinal injury via modulation of TLR4 and NOD signaling pathways. Twenty-four weaned piglets were used in a 2 × 2 factorial design and the main factors included a dietary treatment (5% corn oil or 5% fish oil) and immunological challenge (LPS or saline). After feeding fish oil or corn oil diets for 21 d, pigs were injected with LPS or saline. At 4 h postinjection, blood samples were collected and pigs were killed. EPA, DHA, and total (n-3) PUFA were enriched in intestinal mucosa through fish supplementation. Fish oil improved intestinal morphology, indicated by greater villus height and villus height:crypt depth ratio, and intestinal barrier function, indicated by decreased plasma diamine oxidase (DAO) activity and increased mucosal DAO activity as well as enhanced protein expression of intestinal tight junction proteins including occludin and claudin-1. Moreover, fish oil decreased intestinal TNFα and PGE(2) concentrations and caspase-3 and heat shock protein 70 protein expression. Finally, fish oil downregulated the mRNA expression of intestinal TLR4 and its downstream signals myeloid differentiation factor 88, IL-1 receptor-associated kinase 1, TNFα receptor-associated factor 6, and NOD2, and its adaptor molecule, receptor-interacting serine/threonine-protein kinase 2. Fish oil decreased the protein expression of intestinal NFκB p65. These results indicate that fish oil supplementation is associated with inhibition of TLR4 and NOD2 signaling pathways and concomitant improvement of intestinal integrity under an inflammatory condition.

  11. Studies with inulin-type fructans on intestinal infections, permeability, and inflammation.

    PubMed

    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.

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

    PubMed Central

    Baranwal, Somesh

    2015-01-01

    Adherens junctions (AJs) and tight junctions (TJs) are crucial regulators of the integrity and restitution of the intestinal epithelial barrier. The structure and function of epithelial junctions depend on their association with the cortical actin cytoskeleton that, in polarized epithelial cells, is represented by a prominent perijunctional actomyosin belt. The assembly and stability of the perijunctional cytoskeleton is controlled by constant turnover (disassembly and reassembly) of actin filaments. Actin-interacting protein (Aip) 1 is an emerging regulator of the actin cytoskeleton, playing a critical role in filament disassembly. In this study, we examined the roles of Aip1 in regulating the structure and remodeling of AJs and TJs in human intestinal epithelium. Aip1 was enriched at apical junctions in polarized human intestinal epithelial cells and normal mouse colonic mucosa. Knockdown of Aip1 by RNA interference increased the paracellular permeability of epithelial cell monolayers, decreased recruitment of AJ/TJ proteins to steady-state intercellular contacts, and attenuated junctional reassembly in a calcium-switch model. The observed defects of AJ/TJ structure and functions were accompanied by abnormal organization and dynamics of the perijunctional F-actin cytoskeleton. Moreover, loss of Aip1 impaired the apico-basal polarity of intestinal epithelial cell monolayers and inhibited formation of polarized epithelial cysts in 3-D Matrigel. Our findings demonstrate a previously unanticipated role of Aip1 in regulating the structure and remodeling of intestinal epithelial junctions and early steps of epithelial morphogenesis. PMID:25792565

  13. Absorption of thiamine and nicotinic acid in the rat intestine during fasting and immobilization stress

    NASA Technical Reports Server (NTRS)

    Kirilyuk, O. G.; Khmelevskiy, Y. V.

    1980-01-01

    By perfusion of isolated sections of intestine with a solution containing thiamine at a concentration of 3.1 micromole, it was established that thiamine absorption in animals fasted for 72 hours decreased by 28 percent, whereas absorption increased by 12 percent in rats after 24 hour immobilization. After immobilization, absorption of label in the intestinal mucosa increased. Na K ATPase activity in the intestinal mucosa decreased by 10 percent during fasting, and it increased with immobilization of the animals. Activity of Na K ATPase in the intestinal mucosa cells determined the absorption rate of thiamine and nicotinic acid at the level of vitamin transport through the plasma membranes of the enterocytes.

  14. Probiotic supplementation affects markers of intestinal barrier, oxidation, and inflammation in trained men; a randomized, double-blinded, placebo-controlled trial

    PubMed Central

    2012-01-01

    Background Probiotics are an upcoming group of nutraceuticals claiming positive effects on athlete’s gut health, redox biology and immunity but there is lack of evidence to support these statements. Methods We conducted a randomized, double-blinded, placebo controlled trial to observe effects of probiotic supplementation on markers of intestinal barrier, oxidation and inflammation, at rest and after intense exercise. 23 trained men received multi-species probiotics (1010 CFU/day, Ecologic®Performance or OMNi-BiOTiC®POWER, n = 11) or placebo (n = 12) for 14 weeks and performed an intense cycle ergometry over 90 minutes at baseline and after 14 weeks. Zonulin and α1-antitrypsin were measured from feces to estimate gut leakage at baseline and at the end of treatment. Venous blood was collected at baseline and after 14 weeks, before and immediately post exercise, to determine carbonyl proteins (CP), malondialdehyde (MDA), total oxidation status of lipids (TOS), tumor necrosis factor-alpha (TNF-α), and interleukin-6 (IL-6). Statistical analysis used multifactorial analysis of variance (ANOVA). Level of significance was set at p < 0.05, a trend at p < 0.1. Results Zonulin decreased with supplementation from values slightly above normal into normal ranges (<30 ng/ml) and was significantly lower after 14 weeks with probiotics compared to placebo (p = 0.019). We observed no influence on α1-antitrypsin (p > 0.1). CP increased significantly from pre to post exercise in both groups at baseline and in the placebo group after 14 weeks of treatment (p = 0.006). After 14 weeks, CP concentrations were tendentially lower with probiotics (p = 0.061). TOS was slightly increased above normal in both groups, at baseline and after 14 weeks of treatment. There was no effect of supplementation or exercise on TOS. At baseline, both groups showed considerably higher TNF-α concentrations than normal. After 14 weeks TNF-α was

  15. Relationship between the pH of enema solutions and intestinal damage in rabbits.

    PubMed

    Zhang, Feng; Li, Xia; Xu, Xujuan; Cai, Duanying; Zhang, Jianguo

    2015-01-01

    Mechanical enemas can lead to intestinal mucosal injuries and bowel barrier damage, presenting as electrolyte disturbances and functional intestinal disorders. Most researchers believe that the mechanism of injury is related to osmolality, volume and temperature of the solution, infusion pressure, and the composition of the enema tube. We hypothesized that the pH of the enema solution may also contribute to intestinal damage. We administered enema solutions--normal saline, soapsuds, or vinegar (neutral, alkaline, or acidic solutions, respectively)--to three groups of rabbits (n = 20 per group). The solutions were standardized for volume and temperature and the soapsuds and vinegar solutions were adjusted to be isotonic with normal saline or deionized water. We also included a control group (n = 20) in which the enema tubes were inserted but no solution was administered. We biopsied 3 sites (rectum and distal and proximal colon). Damage to intestinal mucosa was observed by light microscopy and transmission electron microscopy. In order to explore the detection of damage using noninvasive methods, cyclooxygenase (COX)-2 gene expression was measured in the exfoliated cells gathered from postenema defecation. Epithelial loss, inflammatory reaction, and cellular microstructure damage was increased in the vinegar and soapsuds groups. Also, exfoliated cells in these groups had higher COX-2 expression than the normal saline group. The acidic and alkaline enema solutions thus caused more severe damage to the intestinal mucosa compared to the neutral liquid, supporting our hypothesis. Further, the detection of COX-2 expression shows promise as a noninvasive method for estimating enema-induced damage.

  16. Epithelial NEMO links innate immunity to chronic intestinal inflammation.

    PubMed

    Nenci, Arianna; Becker, Christoph; Wullaert, Andy; Gareus, Ralph; van Loo, Geert; Danese, Silvio; Huth, Marion; Nikolaev, Alexei; Neufert, Clemens; Madison, Blair; Gumucio, Deborah; Neurath, Markus F; Pasparakis, Manolis

    2007-03-29

    Deregulation of intestinal immune responses seems to have a principal function in the pathogenesis of inflammatory bowel disease. The gut epithelium is critically involved in the maintenance of intestinal immune homeostasis-acting as a physical barrier separating luminal bacteria and immune cells, and also expressing antimicrobial peptides. However, the molecular mechanisms that control this function of gut epithelial cells are poorly understood. Here we show that the transcription factor NF-kappaB, a master regulator of pro-inflammatory responses, functions in gut epithelial cells to control epithelial integrity and the interaction between the mucosal immune system and gut microflora. Intestinal epithelial-cell-specific inhibition of NF-kappaB through conditional ablation of NEMO (also called IkappaB kinase-gamma (IKKgamma)) or both IKK1 (IKKalpha) and IKK2 (IKKbeta)-IKK subunits essential for NF-kappaB activation-spontaneously caused severe chronic intestinal inflammation in mice. NF-kappaB deficiency led to apoptosis of colonic epithelial cells, impaired expression of antimicrobial peptides and translocation of bacteria into the mucosa. Concurrently, this epithelial defect triggered a chronic inflammatory response in the colon, initially dominated by innate immune cells but later also involving T lymphocytes. Deficiency of the gene encoding the adaptor protein MyD88 prevented the development of intestinal inflammation, demonstrating that Toll-like receptor activation by intestinal bacteria is essential for disease pathogenesis in this mouse model. Furthermore, NEMO deficiency sensitized epithelial cells to tumour-necrosis factor (TNF)-induced apoptosis, whereas TNF receptor-1 inactivation inhibited intestinal inflammation, demonstrating that TNF receptor-1 signalling is crucial for disease induction. These findings demonstrate that a primary NF-kappaB signalling defect in intestinal epithelial cells disrupts immune homeostasis in the gastrointestinal tract

  17. Denatured globular protein and bile salt-coated nanoparticles for poorly water-soluble drugs: Penetration across the intestinal epithelial barrier into the circulation system and enhanced oral bioavailability.

    PubMed

    He, Wei; Yang, Ke; Fan, Lifang; Lv, Yaqi; Jin, Zhu; Zhu, Shumin; Qin, Chao; Wang, Yiao; Yin, Lifang

    2015-11-10

    Oral drug delivery is the most preferred route for patients; however, the low solubility of drugs and the resultant poor absorption compromise the benefits of oral administration. On the other hand, for years, the overwhelmingly accepted mechanism for enhanced oral absorption using lipid nanocarriers was based on the process of lipid digestion and drug solubilization in the small intestine. Few reports indicated that other bypass pathways are involved in drug absorption in the gastrointestinal tract (GIT) for oral delivery of nanocarriers. Herein, we report a new nanoemulsion system with a denatured globular protein with a diameter of 30 nm, soybean protein isolates (SPI), and bile salt as emulsifiers, aiming to enhance the absorption of insoluble drugs and explore other pathways for absorption. A BCS class II drug, fenofibrate (FB), was used as the model drug. The SPI and bile salt-coated Ns with a diameter of approximately 150 nm were prepared via a high-pressure homogenizing procedure. Interestingly, the present Ns could be converted to solid dosage form using fluid-bed coating technology, maintaining a nanoscale size. Most importantly, in a model of in situ rat intestinal perfusion, Ns could penetrate across the intestinal epithelial barrier into the systemic circulation and then obtain biodistribution into other tissues. In addition, Ns significantly improved FB oral absorption, exhibited as a greater than 2- and 2.5-fold increase in Cmax and AUC0-t, respectively, compared to the suspension formulation. Overall, the present Ns are promising nanocarriers for the oral delivery of insoluble drugs, and the penetration of intact Ns across the GIT barrier into systemic circulation may be a new strategy for improved drug absorption with the use of nanocarriers.

  18. Phenotype and Tissue Residency of Lymphocytes in the Murine Oral Mucosa

    PubMed Central

    Park, Joo-Young; Chung, Hyunsoo; Choi, Youngnim; Park, Jung-Hyun

    2017-01-01

    The oral mucosa is a critical barrier tissue that harbors a series of distinct immune cell subsets. Immune surveillance in the oral mucosa is important for both local and systemic immunity because the oral cavity is a heavily utilized route of pathogen entry and also serves as site of pathogen propagation. Nonetheless, composition and phenotype of the lymphocyte pool in the oral mucosa have remained poorly characterized. Utilizing a newly established protocol for mucosal immune cell isolation, here, we report that the oral mucosa features a unique cellular composition of immune cells, which differed not only from secondary lymphoid organs but also from mucosal tissues in the gut and lung. We observed profound accumulation of CD11b+Ly6Clo monocytes in the oral mucosa that were maintained independently of T- and B-lymphocytes. Unlike the gut mucosa, the oral mucosa neither contained CD8αα T cells nor was it enriched for CD103+CD69+ tissue-resident memory CD8 T cells. In fact, a major fraction of T cells circulated and trafficked through the mucosa as revealed by treatment with the S1P1 receptor antagonist, FTY720, a potent inhibitor of lymphocyte migration. Collectively, these results provide a comprehensive picture of immune cells in the oral mucosa as an active site of lymphocyte recruitment and surveillance. PMID:28337201

  19. Intestinal Cancer

    MedlinePlus

    ... connects your stomach to your large intestine. Intestinal cancer is rare, but eating a high-fat diet ... increase your risk. Possible signs of small intestine cancer include Abdominal pain Weight loss for no reason ...

  20. Intestinal leiomyoma

    MedlinePlus

    Leiomyoma - intestine ... McLaughlin P, Maher MM. The duodenum and small intestine. In: Adam A, Dixon AK, Gillard JH, Schaefer- ... Roline CE, Reardon RF. Disorders of the small intestine. In: Marx JA, Hockberger RS, Walls RM, et ...

  1. Intestinal obstruction

    MedlinePlus

    Paralytic ileus; Intestinal volvulus; Bowel obstruction; Ileus; Pseudo-obstruction - intestinal; Colonic ileus ... objects that are swallowed and block the intestines) Gallstones (rare) Hernias Impacted stool Intussusception (telescoping of 1 ...

  2. Intestinal Obstruction

    MedlinePlus

    An intestinal obstruction occurs when food or stool cannot move through the intestines. The obstruction can be complete or partial. ... abdomen Inability to pass gas Constipation A complete intestinal obstruction is a medical emergency. It often requires surgery. ...

  3. Modulation of the intestinal environment, innate immune response, and barrier function by dietary threonine and purified fiber during a coccidiosis challenge in broiler chicks

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Coccidiosis is a major contributor to economic losses in the poultry industry due to its detrimental effects on growth performance and nutrient utilization. We hypothesized that the combined effects of supplemental dietary Thr and purified fiber may modulate the intestinal environment and positively...

  4. Claudins in intestines

    PubMed Central

    Lu, Zhe; Ding, Lei; Lu, Qun; Chen, Yan-Hua

    2013-01-01

    Intestines are organs that not only digest food and absorb nutrients, but also provide a defense barrier against pathogens and noxious agents ingested. Tight junctions (TJs) are the most apical component of the junctional complex, providing one form of cell-cell adhesion in enterocytes and playing a critical role in regulating paracellular barrier permeability. Alteration of TJs leads to a number of pathophysiological diseases causing malabsorption of nutrition and intestinal structure disruption, which may even contribute to systemic organ failure. Claudins are the major structural and functional components of TJs with at least 24 members in mammals. Claudins have distinct charge-selectivity, either by tightening the paracellular pathway or functioning as paracellular channels, regulating ions and small molecules passing through the paracellular pathway. In this review, we have discussed the functions of claudin family members, their distribution and localization in the intestinal tract of mammals, their alterations in intestine-related diseases and chemicals/agents that regulate the expression and localization of claudins as well as the intestinal permeability, which provide a therapeutic view for treating intestinal diseases. PMID:24478939

  5. Composition and diversity of mucosa-associated microbiota along the entire length of the pig gastrointestinal tract; dietary influences.

    PubMed

    Kelly, Jennifer; Daly, Kristian; Moran, Andrew W; Ryan, Sheila; Bravo, David; Shirazi-Beechey, Soraya P

    2017-04-01

    Mucosa-associated microbial populations of the gastrointestinal tract are in intimate contact with the outer mucus layer. This proximity offers these populations a higher potential, than lumenal microbiota, in exerting effects on the host. Functional characteristics of the microbiota and influences of host-physiology shape the composition and activity of the mucosa-associated bacterial community. We have shown previously that inclusion of an artificial sweetener, SUCRAM, included in the diet of weaning piglets modulates the composition of lumenal-residing gut microbiota and reduces weaning-related gastrointestinal disorders. In this study, using Illumina sequencing we characterised the mucosa-associated microbiota along the length of the intestine of piglets, and determined the effect of SUCRAM supplementation on mucosa-associated populations. There were clear distinctions in the composition of mucosa-associated microbiota, between small and large intestine, concordant with differences in regional oxygen distribution and nutrient provision by the host. There were significant differences in the composition of mucosa-associated compared with lumenal microbiota in pig caecum. Dietary supplementation with SUCRAM affected mucosa-associated bacterial community structure along the length of the intestinal tract. Most notably, there was a substantial reduction in predominant Campylobacter populations proposing that SUCRAM supplementation of swine diet has potential for reducing meat contamination and promoting food safety.

  6. Vermilion Reconstruction with Genital Mucosa

    PubMed Central

    Weyandt, Gerhard H.; Woeckel, Achim; Kübler, Alexander C.

    2016-01-01

    Summary: Functional and aesthetical reconstruction, especially of the upper lip after ablative tumor surgery, can be very challenging. The skin of the lip might be sufficiently reconstructed by transpositional flaps from the nasolabial or facial area. Large defects of the lip mucosa, including the vestibule, are even more challenging due to the fact that flaps from the inner lining of the oral cavity often lead to functional impairments. We present a case of multiple vermilion and skin resections of the upper lip. At the last step, we had to resect even the whole vermilion mucosa, including parts of the oral mucosa of the vestibule, leaving a bare orbicularis oris muscle. To reconstruct the mucosal layer, we used a mucosal graft from the labia minora and placed it on the compromised lip and the former transpositional flaps for the reconstructed skin of the upper lip with very good functional and aesthetic results. PMID:27579226

  7. Vermilion Reconstruction with Genital Mucosa.

    PubMed

    Müller-Richter, Urs D A; Weyandt, Gerhard H; Woeckel, Achim; Kübler, Alexander C

    2016-05-01

    Functional and aesthetical reconstruction, especially of the upper lip after ablative tumor surgery, can be very challenging. The skin of the lip might be sufficiently reconstructed by transpositional flaps from the nasolabial or facial area. Large defects of the lip mucosa, including the vestibule, are even more challenging due to the fact that flaps from the inner lining of the oral cavity often lead to functional impairments. We present a case of multiple vermilion and skin resections of the upper lip. At the last step, we had to resect even the whole vermilion mucosa, including parts of the oral mucosa of the vestibule, leaving a bare orbicularis oris muscle. To reconstruct the mucosal layer, we used a mucosal graft from the labia minora and placed it on the compromised lip and the former transpositional flaps for the reconstructed skin of the upper lip with very good functional and aesthetic results.

  8. Development of intestinal transport function in mammals.

    PubMed

    Pácha, J

    2000-10-01

    Considerable progress has been made over the last decade in the understanding of mechanisms responsible for the ontogenetic changes of mammalian intestine. This review presents the current knowledge about the development of intestinal transport function in the context of intestinal mucosa ontogeny. The review predominantly focuses on signals that trigger and/or modulate the developmental changes of intestinal transport. After an overview of the proliferation and differentiation of intestinal mucosa, data about the bidirectional traffic (absorption and secretion) across the developing intestinal epithelium are presented. The largest part of the review is devoted to the description of developmental patterns concerning the absorption of nutrients, ions, water, vitamins, trace elements, and milk-borne biologically active substances. Furthermore, the review examines the development of intestinal secretion that has a variety of functions including maintenance of the fluidity of the intestinal content, lubrication of mucosal surface, and mucosal protection. The age-dependent shifts of absorption and secretion are the subject of integrated regulatory mechanisms, and hence, the input of hormonal, nervous, immune, and dietary signals is reviewed. Finally, the utilization of energy for transport processes in the developing intestine is highlighted, and the interactions between various sources of energy are discussed. The review ends with suggestions concerning possible directions of future research.

  9. Bovine colostrum increases pore-forming claudin-2 protein expression but paradoxically not ion permeability possibly by a change of the intestinal cytokine milieu.

    PubMed

    Bodammer, Peggy; Kerkhoff, Claus; Maletzki, Claudia; Lamprecht, Georg

    2013-01-01

    An impaired intestinal barrier function is involved in the pathogenesis of inflammatory bowel disease (IBD). Several nutritional factors are supposed to be effective in IBD treatment but scientific data about the effects on the intestinal integrity remain scarce. Bovine colostrum was shown to exert beneficial effects in DSS-induced murine colitis, and the present study was undertaken to explore the underlying molecular mechanisms. Western blot revealed increased claudin-2 expression in the distal ileum of healthy mice after feeding with colostrum for 14 days, whereas other tight junction proteins (claudin-3, 4, 10, 15) remained unchanged. The colostrum-induced claudin-2 induction was confirmed in differentiated Caco-2 cells after culture with colostrum for 48 h. Paradoxically, the elevation of claudin-2, which forms a cation-selective pore, was neither accompanied by increased ion permeability nor impaired barrier function. In an in situ perfusion model, 1 h exposure of the colonic mucosa to colostrum induced significantly increased mRNA levels of barrier-strengthening cytokine transforming growth factor-β, while interleukine-2, interleukine-6, interleukine-10, interleukine-13, and tumor-necrosis factor-α remained unchanged. Thus, modulation of the intestinal transforming growth factor-β expression might have compensated the claudin-2 increase and contributed to the observed barrier strengthening effects of colostrum in vivo and in vitro.

  10. Ammonia inhibits cAMP-regulated intestinal Cl- transport. Asymmetric effects of apical and basolateral exposure and implications for epithelial barrier function.

    PubMed Central

    Prasad, M; Smith, J A; Resnick, A; Awtrey, C S; Hrnjez, B J; Matthews, J B

    1995-01-01

    The colon, unlike most organs, is normally exposed to high concentrations of ammonia, a weak base which exerts profound and diverse biological effects on mammalian cells. The impact of ammonia on intestinal cell function is largely unknown despite its concentration of 4-70 mM in the colonic lumen. The human intestinal epithelial cell line T84 was used to model electrogenic Cl- secretion, the transport event which hydrates mucosal surfaces and accounts for secretory diarrhea. Transepithelial transport and isotopic flux analysis indicated that physiologically-relevant concentrations of ammonia (as NH4Cl) markedly inhibit cyclic nucleotide-regulated Cl- secretion but not the response to the Ca2+ agonist carbachol. Inhibition by ammonia was 25-fold more potent with basolateral compared to apical exposure. Ion substitution indicated that the effect of NH4Cl was not due to altered cation composition or membrane potential. The site of action of ammonia is distal to cAMP generation and is not due simply to cytoplasmic alkalization. The results support a novel role for ammonia as an inhibitory modulator of intestinal epithelial Cl- secretion. Secretory responsiveness may be dampened in pathological conditions associated with increased mucosal permeability due to enhanced access of lumenal ammonia to the basolateral epithelial compartment. Images PMID:7593599

  11. Morpho-elasticity of intestinal villi

    PubMed Central

    Balbi, V.; Ciarletta, P.

    2013-01-01

    Villi are ubiquitous structures in the intestine of all vertebrates, originating from the embryonic development of the epithelial mucosa. Their morphogenesis has similar stages in living organisms but different forming mechanisms. In this work, we model the emergence of the bi-dimensional undulated patterns in the intestinal mucosa from which villi start to elongate. The embryonic mucosa is modelled as a growing thick-walled cylinder, and its mechanical behaviour is described using an hyperelastic constitutive model, which also accounts for the anisotropic characteristics of the reinforcing fibres at the microstructural level. The occurrence of surface undulations is investigated using a linear stability analysis based on the theory of incremental deformations superimposed on a finite deformation. The Stroh formulation of the incremental boundary value problem is derived, and a numerical solution procedure is implemented for calculating the growth thresholds of instability. The numerical results are finally discussed with respect to different growth and materials properties. In conclusion, we demonstrate that the emergence of intestinal villi in embryos is triggered by a differential growth between the mucosa and the mesenchymal tissues. The proposed model quantifies how both the geometrical and the mechanical properties of the mucosa drive the formation of previllous structures in embryos. PMID:23486174

  12. Saccharomyces cerevisiae UFMG A-905 treatment reduces intestinal damage in a murine model of irinotecan-induced mucositis.

    PubMed

    Bastos, R W; Pedroso, S H S P; Vieira, A T; Moreira, L M C; França, C S; Cartelle, C T; Arantes, R M E; Generoso, S V; Cardoso, V N; Neves, M J; Nicoli, J R; Martins, F S

    2016-09-01

    Indigenous microbiota plays a crucial role in the development of several intestinal diseases, including mucositis. Gastrointestinal mucositis is a major and serious side effect of cancer therapy, and there is no effective therapy for this clinical condition. However, some probiotics have been shown to attenuate such conditions. To evaluate the effects of Saccharomyces cerevisiae UFMG A-905 (Sc-905), a potential probiotic yeast, we investigated whether pre- or post-treatment with viable or inactivated Sc-905 could prevent weight loss and intestinal lesions, and maintain integrity of the mucosal barrier in a mucositis model induced by irinotecan in mice. Only post-treatment with viable Sc-905 was able to protect mice against the damage caused by chemotherapy, reducing the weight loss, increase of intestinal permeability and jejunal lesions (villous shortening). Besides, this treatment reduced oxidative stress, prevented the decrease of goblet cells and stimulated the replication of cells in the intestinal crypts of mice with experimental mucositis. In conclusion, Sc-905 protects animals against irinotecan-induced mucositis when administered as a post-treatment with viable cells, and this effect seems to be related with the reduction of oxidative stress and preservation of intestinal mucosa.

  13. Neutrophil-derived JAML Inhibits Repair of Intestinal Epithelial Injury During Acute Inflammation

    PubMed Central

    Weber, Dominique A.; Sumagin, Ronen; McCall, Ingrid C.; Leoni, Giovanna; Neumann, Philipp A.; Andargachew, Rakieb; Brazil, Jennifer C.; Medina-Contreras, Oscar; Denning, Timothy L.; Nusrat, Asma; Parkos, Charles A.

    2014-01-01

    Neutrophil transepithelial migration (TEM) during acute inflammation is associated with mucosal injury. Using models of acute mucosal injury in-vitro and in-vivo, we describe a new mechanism by which neutrophils infiltrating the intestinal mucosa disrupt epithelial homeostasis. We report that junctional adhesion molecule-like protein (JAML) is cleaved from neutrophil surface by zinc-metalloproteases during TEM. Neutrophil-derived soluble JAML bound to the epithelial tight junction protein coxsackie-adenovirus receptor (CAR) resulting in compromised barrier and inhibition of wound repair, through decreased epithelial proliferation. The deleterious effects of JAML on barrier and wound repair were reversed with an anti-JAML mAb that inhibits JAML-CAR binding. Thus, JAML released from transmigrating neutrophils across inflamed epithelia can promote recruitment of leukocytes and aid in clearance of invading microorganisms. However, sustained release of JAML under pathologic conditions associated with persistence of large numbers of infiltrated neutrophil would compromise intestinal barrier and inhibit mucosal healing. Targeting JAML-CAR interactions may thus improve mucosal healing responses under conditions of dysregulated neutrophil recruitment. PMID:24621992

  14. Acute enteral glutamine infusion enhances heme oxygenase-1 expression in human duodenal mucosa.

    PubMed

    Coëffier, Moïse; Le Pessot, Florence; Leplingard, Antony; Marion, Rachel; Lerebours, Eric; Ducrotté, Philippe; Déchelotte, Pierre

    2002-09-01

    The heat shock protein, heme oxygenase-1 (HO-1), contributes to the protection of the intestine. Some experimental models suggest that induction of HO-1 by glutamine may contribute to the preservation of intestinal mucosa. The effect of an enteral infusion of glutamine for 6 h on HO-1 expression in duodenal mucosa was studied in healthy men and women and compared with an isonitrogenous mixture of amino acids. After enteral infusion, endoscopic duodenal biopsies were performed and either fixed in formalin for immunohistochemistry or frozen for HO-1 mRNA analysis by reverse transcriptase-polymerase chain reaction. Histologic examination revealed that HO-1 was constitutively expressed in intestinal epithelial cells (IEC), and that glutamine increased the grade of HO-1 immunostaining (P mucosa. These data support further evaluation of the effects of glutamine on intestinal HO-1 during states of intestinal inflammation.

  15. Effects of P-glycoprotein on the intestine and blood-brain barrier transport of YZG-331, a promising sedative-hypnotic compound.

    PubMed

    Liu, Zhihao; Mi, Jiaqi; Yang, Shuang; Zhao, Manman; Li, Yan; Sheng, Li

    2016-11-15

    YZG-331 is a synthetic adenosine analogue which exhibits the sedative and hypnotic effects by binding to the adenosine receptor. The present study was designed to investigate the effects of P-glycoprotein (P-gp) on the intestine and brain distribution of YZG-331 in vitro and in vivo as well as related binding mechanisms. The activity of P-gp ATPase was both induced by YZG-331 and verapamil, a typical P-gp inhibitor, but affinity of YZG-331 for P-gp was lower than that of verapamil. The docking analyses further elucidated the binding relationship of YZG-331 and P-gp. The directional transport of YZG-331 was disappeared in Caco-2 and MDCK-MDR1 cells when the P-gp activity was blocked. However, the penetration of digoxin, a P-gp known substrate, was not change in MDCK-MDR1 cells along with YZG-331. In the everted intestinal sac model, the influx of YZG-331 was significantly reduced in the presence of verapamil in all the segments except for the colon. In the in situ and in vivo study, the brain exposure of YZG-331 was promoted after co-administered of verapamil. Furthermore, the Kp value changed from 0.03 to 0.05 after drug combination. Taken together, these results indicated that YZG-331 is a substrate but may not an inhibitor of P-gp. The intestine and brain permeability of YZG-331 can be restricted, at least in part, by P-gp. The drug interactions should be awarded when YZG-331 and other P-gp-related drugs used together.

  16. Differential cloning of novel intestine-specific genes whose expression is altered under conditions of villus atrophy.

    PubMed

    Hodin, R A; Meng, S; Shei, A

    1995-07-01

    Atrophy of the small intestinal villi occurs in a variety of disease states and is associated with diarrhea, malabsorption, and impaired barrier function. We have previously demonstrated that villus atrophy is associated with an increase in lactase and a decrease in intestinal alkaline phosph