scholarly journals EIMERIA TENELLA INFECTION MODULATES THE EXPRESSION LEVELS OF INTESTINAL EPITHELIAL BARRIER-RELATED GENES IN CHICKEN

2021 ◽  
Vol 10 (Supplement) ◽  
pp. MR04_p13-MR04_p16
Author(s):  
Hung Hoang Son PHAM ◽  
Toshimitsu HATABU
Keyword(s):  
Eimeria Tenella ◽  
Epithelial Barrier ◽  
Intestinal Epithelial ◽  
Intestinal Epithelial Barrier ◽  
Expression Levels

scholarly journals Retinoic Acid Facilitates Toll-Like Receptor 4 Expression to Improve Intestinal Barrier Function through Retinoic Acid Receptor Beta

2017 ◽  
Vol 42 (4) ◽  
pp. 1390-1406 ◽  
Author(s):  
Yingying Li ◽  
Yuan Gao ◽  
Ting Cui ◽  
Ting Yang ◽  
Lan Liu ◽  
...  
Keyword(s):  
Retinoic Acid ◽  
Barrier Function ◽  
Retinoic Acid Receptor ◽  
Epithelial Barrier ◽  
Intestinal Epithelial ◽  
Toll Like Receptor ◽  
Intestinal Epithelial Barrier ◽  
Epithelial Barrier Function ◽  
Expression Levels ◽  
Acid Receptor

Background/Aims: Vitamin A (VA) protects the intestinal epithelial barrier by improving cell migration and proliferation. Our previous studies demonstrated that VA deficiency (VAD) during pregnancy suppresses the systemic and mucosal immune responses in the intestines of offspring and that VA supplementation (VAS) during early life can increase immune cell counts. However, little is known about the mechanisms by which VA regulates intestinal epithelial barrier function. Methods: Caco-2 cells were treated with all-trans retinoic acid (ATRA) for 24 hours to determine the optimum ATRA concentration to which the cells in question respond. Caco-2 cells were infected with recombinant adenoviruses carrying retinoic acid receptor beta (Ad-RARβ) and small interfering RARβ(siRARβ) to assess the effects of RARβ signalling on the expression of specific proteins. A siTLR4 lentivirus was used to knockdown Toll-like receptor 4 (TLR4) in Caco-2 cells to determine its role in the protective effects of VA on the intestinal epithelial barrier, and experiments involving TLR4-knock-out mice were performed to verify the effect of TLR4. VA normal (VAN), VAD and VAS rat models were established to confirm that changes in RARβ, TLR4 and ZO-2 expression levels that occurred following decreases or increases in retinol concentrations in vivo, and the permeability of the Caco-2 cell monolayer, as well as that of the epithelial barrier of the rat intestine was detected by measuring transepithelial resistance (TER) or performing enzyme-linked immunosorbent assay (ELISA). Retinoic acid receptor (RAR), toll like receptor (TLR) and tight junction (TJ) mRNA and protein expression levels in Caco-2 cells and the colon monolayers in the rat and mouse models were measured by PCR and western blotting, respectively. Co-immunoprecipitation (co-IP) and immunofluorescence staining were performed to assess the interactions among RARβ, TLR4 and zonula occluden-2 (ZO-2) in Caco-2 cells, and chromatin immunoprecipitation (ChIP) assay was performed to assess the binding between RARβ and the TLR4 promoter sequence in Caco-2 cells. Results: In the present study, ATRA treatment not only increased the TER of the Caco-2 monolayer but also up-regulated the expression levels of RARβ, TLR4 and ZO-2 in Caco-2 cells. The expression levels of these three proteins were significantly decreased in the colonic epithelial monolayers of VAD rats compared with those of VAN rats and were significantly increased following VAS in the corresponding group compared with the control group. Furthermore, the above changes in TLR4 and ZO-2 expression levels were augmented or attenuated by Ad-RARβ or siRARβ infection, respectively, in Caco-2 cells. Interestingly, siTLR4 down-regulated ZO-2 expression but did not affect RARβ expression in Caco-2 cells, and in VAD mice the lack of TLR4 did not affect ZO-2 expression. We noted direct interactions between RARβ and TLR4, TLR4 and ZO-2 in Caco-2 cells, and ChIP assay showed that RARβ could bind to the TLR4 promoter but not the ZO-2 promoter in Caco-2 cells. Conclusion: Taken together, our results indicate that RARβ enhanced ZO-2 expression by regulating TLR4 to improve intestinal epithelial barrier function in Caco-2 cells, as well as in rat and mouse models, but not in humans.

scholarly journals A Novel Pharmacological Approach to Enhance the Integrity and Accelerate Restitution of the Intestinal Epithelial Barrier

2020 ◽  
Vol 26 (9) ◽  
pp. 1340-1352
Author(s):  
Xuelei Cao ◽  
Lei Sun ◽  
Susana Lechuga ◽  
Nayden G Naydenov ◽  
Alex Feygin ◽  
...  
Keyword(s):  
Wound Healing ◽  
Epithelial Cell ◽  
Epithelial Barrier ◽  
Intestinal Epithelial ◽  
Intestinal Epithelial Barrier ◽  
Cell Monolayers ◽  
Barrier Disruption ◽  
Epithelial Cell Monolayers ◽  
Immunofluorescence Labeling ◽  
E Cadherin

Abstract Background Disruption of the gut barrier is an essential mechanism of inflammatory bowel diseases (IBDs) contributing to the development of mucosal inflammation. A hallmark of barrier disruption is the disassembly of epithelial adherens junctions (AJs) driven by decreased expression of a major AJ protein, E-cadherin. A group of isoxazole compounds, such as E-cadherin-upregulator (ECU) and ML327, were previously shown to stimulate E-cadherin expression in poorly differentiated human cancer cells. This study was designed to examine whether these isoxazole compounds can enhance and protect model intestinal epithelial barriers in vitro. Methods The study was conducted using T84, SK-CO15, and HT-29 human colonic epithelial cell monolayers. Disruption of the epithelial barrier was induced by pro-inflammatory cytokines, tumor necrosis factor-α, and interferon-γ. Barrier integrity and epithelial junction assembly was examined using different permeability assays, immunofluorescence labeling, and confocal microscopy. Epithelial restitution was analyzed using a scratch wound healing assay. Results E-cadherin-upregulator and ML327 treatment of intestinal epithelial cell monolayers resulted in several barrier-protective effects, including reduced steady-state epithelial permeability, inhibition of cytokine-induced barrier disruption and junction disassembly, and acceleration of epithelial wound healing. Surprisingly, these effects were not due to upregulation of E-cadherin expression but were mediated by multiple mechanisms including inhibition of junction protein endocytosis, attenuation of cytokine-induced apoptosis, and activation of promigratory Src and AKT signaling. Conclusions Our data highlight ECU and ML327 as promising compounds for developing new therapeutic strategies to protect the integrity and accelerate the restitution of the intestinal epithelial barrier in IBD and other inflammatory disorders.

The enteric nervous system as a regulator of intestinal epithelial barrier function in health and disease

2010 ◽  
Vol 4 (5) ◽  
pp. 637-651 ◽  
Author(s):  
Susanne A Snoek ◽  
Marleen I Verstege ◽  
Guy E Boeckxstaens ◽  
René M van den Wijngaard ◽  
Wouter J de Jonge
Keyword(s):  
Nervous System ◽  
Enteric Nervous System ◽  
Barrier Function ◽  
Epithelial Barrier ◽  
Intestinal Epithelial ◽  
Intestinal Epithelial Barrier ◽  
Epithelial Barrier Function ◽  
Health And Disease

scholarly journals JunD Represses Transcription and Translation of the Tight Junction Protein Zona Occludens-1 Modulating Intestinal Epithelial Barrier Function

2008 ◽  
Vol 19 (9) ◽  
pp. 3701-3712 ◽  
Author(s):  
Jie Chen ◽  
Lan Xiao ◽  
Jaladanki N. Rao ◽  
Tongtong Zou ◽  
Lan Liu ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Tight Junction ◽  
Barrier Function ◽  
Intestinal Epithelial Cells ◽  
Binding Protein ◽  
Mrna Translation ◽  
Epithelial Barrier ◽  
Intestinal Epithelial ◽  
Intestinal Epithelial Barrier ◽  
Epithelial Barrier Function

The AP-1 transcription factor JunD is highly expressed in intestinal epithelial cells, but its exact role in maintaining the integrity of intestinal epithelial barrier remains unknown. The tight junction (TJ) protein zonula occludens (ZO)-1 links the intracellular domain of TJ-transmembrane proteins occludin, claudins, and junctional adhesion molecules to many cytoplasmic proteins and the actin cytoskeleton and is crucial for assembly of the TJ complex. Here, we show that JunD negatively regulates expression of ZO-1 and is implicated in the regulation of intestinal epithelial barrier function. Increased JunD levels by ectopic overexpression of the junD gene or by depleting cellular polyamines repressed ZO-1 expression and increased epithelial paracellular permeability. JunD regulated ZO-1 expression at the levels of transcription and translation. Transcriptional repression of ZO-1 by JunD was mediated through cAMP response element-binding protein-binding site within its proximal region of the ZO-1-promoter, whereas induced JunD inhibited ZO-1 mRNA translation by enhancing the interaction of the ZO-1 3′-untranslated region with RNA-binding protein T cell-restricted intracellular antigen 1-related protein. These results indicate that JunD is a biological suppressor of ZO-1 expression in intestinal epithelial cells and plays a critical role in maintaining epithelial barrier function.

scholarly journals Intestinal Epithelial Barrier Dysfunction in Food Hypersensitivity

2012 ◽  
Vol 2012 ◽  
pp. 1-11 ◽  
Author(s):  
Linda Chia-Hui Yu
Keyword(s):  
Mast Cell ◽  
Cell Surface ◽  
Critical Role ◽  
Mast Cell Activation ◽  
Epithelial Barrier ◽  
Intestinal Epithelial ◽  
Barrier Dysfunction ◽  
Intestinal Epithelial Barrier ◽  
Food Antigens ◽  
Epithelial Barrier Dysfunction

Intestinal epithelial barrier plays a critical role in the maintenance of gut homeostasis by limiting the penetration of luminal bacteria and dietary allergens, yet allowing antigen sampling for the generation of tolerance. Undigested proteins normally do not gain access to the lamina propria due to physical exclusion by tight junctions at the cell-cell contact sites and intracellular degradation by lysosomal enzymes in enterocytes. An intriguing question then arises: how do macromolecular food antigens cross the epithelial barrier? This review discusses the epithelial barrier dysfunction in sensitized intestine with special emphasis on the molecular mechanism of the enhanced transcytotic rates of allergens. The sensitization phase of allergy is characterized by antigen-induced cross-linking of IgE bound to high affinity FcεRI on mast cell surface, leading to anaphylactic responses. Recent studies have demonstrated that prior to mast cell activation, food allergens are transported in large quantity across the epithelium and are protected from lysosomal degradation by binding to cell surface IgE and low-affinity receptor CD23/FcεRII. Improved immunotherapies are currently under study including anti-IgE and anti-CD23 antibodies for the management of atopic disorders.

scholarly journals Intestinal epithelial barrier function in liver cirrhosis: an extensive review of the literature

2013 ◽  
Vol 33 (10) ◽  
pp. 1457-1469 ◽  
Author(s):  
Kirsten E. Pijls ◽  
Daisy M. A. E. Jonkers ◽  
Elhaseen E. Elamin ◽  
Ad A. M. Masclee ◽  
Ger H. Koek
Keyword(s):  
Liver Cirrhosis ◽  
Barrier Function ◽  
Epithelial Barrier ◽  
Intestinal Epithelial ◽  
Extensive Review ◽  
Review Of The Literature ◽  
Intestinal Epithelial Barrier ◽  
Epithelial Barrier Function

Lactobacillus fermentum L930BB and Bifidobacterium animalis subsp. animalis IM386 initiate signalling pathways involved in intestinal epithelial barrier protection

2018 ◽  
Vol 9 (3) ◽  
pp. 515-525 ◽  
Author(s):  
D. Paveljšek ◽  
P. Juvan ◽  
R. Košir ◽  
D. Rozman ◽  
B. Hacin ◽  
...  
Keyword(s):  
Growth Factor ◽  
Actin Cytoskeleton ◽  
Lactobacillus Fermentum ◽  
Signalling Pathways ◽  
Epithelial Barrier ◽  
Intestinal Epithelial ◽  
Intestinal Epithelial Barrier ◽  
Apoptotic Pathway ◽  
Promising Alternative ◽  
Bifidobacterium Animalis

The manipulation of intestinal microbiota with beneficial microbes represents a promising alternative or adjunct therapy in gastrointestinal disorders and inflammation. The current study aims to clarify the signalling pathways and evaluate the possible beneficial effects of the combination of two strains. We used a dextran sulphate sodium (DSS)-induced mouse model of colitis. RNA extracted from the middle part of the colon tissue was used for examination of the global gene expression with Affymetrix microarrays. An enrichment analysis of the KEGG pathways was performed, and a subset of genes associated with intestinal epithelial barrier function was verified with qPCR. A clinical condition assessment of the differently treated mice revealed that the combination of these two bacterial strains was safe for use as a dietary supplement. All animals treated with DSS had affected colons and suffered weight loss. There were very small differences between the diseased groups, although the depth of inflammation was lower when cyclosporine A or the strain mixture was used. We discovered that the prophylactic administration of the Lactobacillus fermentum L930BB (L930BB) and Bifidobacterium animalis subsp. animalis IM386 (IM386) strains led to an anti-apoptotic pathway through phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3K)/Akt and to the activation of pathways involved in the regulation of actin cytoskeleton via protein kinase C and GTPases. Reorganisation of actin cytoskeleton and decreased apoptosis are both helpful in intestinal epithelial cell reconstitution. We confirm important previous observations, showing that these pathways are downstream targets of Toll-like receptor 2 and fibroblast growth factor initiated signalling. Taken together, these results suggest that the combination of L930BB and IM386 could aid in the regeneration of the intestinal epithelium during pathogenesis via pattern recognition receptors and the stimulation of growth factor synthesis.

scholarly journals Plumericin Protects against Experimental Inflammatory Bowel Disease by Restoring Intestinal Barrier Function and Reducing Apoptosis

Biomedicines ◽  
2021 ◽  
Vol 9 (1) ◽  
pp. 67 ◽  
Author(s):  
Shara Francesca Rapa ◽  
Rosanna Di Paola ◽  
Marika Cordaro ◽  
Rosalba Siracusa ◽  
Ramona D’Amico ◽  
...  
Keyword(s):  
Barrier Function ◽  
Structural Integrity ◽  
Intestinal Barrier ◽  
Intestinal Barrier Function ◽  
Epithelial Barrier ◽  
Intestinal Epithelial ◽  
Intestinal Epithelial Barrier ◽  
Bowel Diseases ◽  
Inflammatory Bowel

Intestinal epithelial barrier impairment plays a key pathogenic role in inflammatory bowel diseases (IBDs). In particular, together with oxidative stress, intestinal epithelial barrier alteration is considered as upstream event in ulcerative colitis (UC). In order to identify new products of natural origin with a potential activity for UC treatment, this study evaluated the effects of plumericin, a spirolactone iridoid, present as one of the main bioactive components in the bark of Himatanthus sucuuba (Woodson). Plumericin was evaluated for its ability to improve barrier function and to reduce apoptotic parameters during inflammation, both in intestinal epithelial cells (IEC-6), and in an animal experimental model of 2, 4, 6-dinitrobenzene sulfonic acid (DNBS)-induced colitis. Our results indicated that plumericin increased the expression of adhesion molecules, enhanced IEC-6 cells actin cytoskeleton rearrangement, and promoted their motility. Moreover, plumericin reduced apoptotic parameters in IEC-6. These results were confirmed in vivo. Plumericin reduced the activity of myeloperoxidase, inhibited the expression of ICAM-1, P-selectin, and the formation of PAR, and reduced apoptosis parameters in mice colitis induced by DNBS. These results support a pharmacological potential of plumericin in the treatment of UC, due to its ability to improve the structural integrity of the intestinal epithelium and its barrier function.

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