Prostate and gut: Any relationship? A narrative review on the available evidence and putative mechanisms.

BACKGROUND: Gut microbiome is a community of microorganisms that lives in the human intestine and exerts various functions on the host, including metabolic, immunoregulatory, and control over cell proliferation. Gut microbiome alterations have been associated with various pathological conditions, such as diabetes mellitus, obesity, and cardiovascular diseases. Gut-prostate axis is explained by the association between gut microbiome quantitative and functional alterations along with increased intestinal epithelial permeability with prostatediseases. However, the pathophysiological mechanisms and clinical importance of this association are not completely clarified yet. METHODS: We conducted a narrative review of the most relevant articles in the Medline (US National Library of Medicine, Bethesda, MD, USA), Scopus (Elsevier, Amsterdam, The Netherlands) and Web of Science Core Collection (Thomson Reuters, Toronto, ON, Canada) databases. No chronological restrictions were applied, and the most related papers published until December 2023 were included. RESULTS: Gut microbiota (GM) and its metabolites are capable of modifying host androgen level, as well as prostate cancer (PCa) therapy response. Moreover, patients with inflammatory bowel disease have higher rates of prostatitis-like symptoms and a potential risk of developing PCa. CONCLUSIONS: There is evidence that interventions on the GM and its metabolites have a high potential to serve as diagnostic and therapeutic tools for prostate diseases, including PCa.

Tetraspanin Tspan8 restrains interferon signaling to stabilize intestinal epithelium by directing endocytosis of interferon receptor.

Inflammation can impair intestinal barrier, while increased epithelial permeability can lead to inflammation. In this study, we found that the expression of Tspan8, a tetraspanin expressed specifically in epithelial cells, is downregulated in mouse model of ulcerative disease (UC) but correlated with those of cell-cell junction components, such as claudins and E-cadherin, suggesting that Tspan8 supports intestinal epithelial barrier. Tspan8 removal increases intestinal epithelial permeability and upregulates IFN-γ-Stat1 signaling. We also demonstrated that Tspan8 coalesces with lipid rafts and facilitates IFNγ-R1 localization at or near lipid rafts. As IFN-γ induces its receptor undergoing clathrin- or lipid raft-dependent endocytosis and IFN-γR endocytosis plays an important role in Jak-Stat1 signaling, our analysis on IFN-γR endocytosis revealed that Tspan8 silencing impairs lipid raft-mediated but promotes clathrin-mediated endocytosis of IFN-γR1, leading to increased Stat1 signaling. These changes in IFN-γR1 endocytosis upon Tspan8 silencing correlates with fewer lipid raft component GM1 at the cell surface and more clathrin heavy chain in the cells. Our findings indicate that Tspan8 determines the IFN-γR1 endocytosis route, to restrain Stat1 signaling, stabilize intestine epithelium, and subsequently prevent intestine from inflammation. Our finding also implies that Tspan8 is needed for proper endocytosis through lipid rafts.

Colonic Epithelial Permeability to Ions Is Restored after Vedolizumab Treatment and May Predict Clinical Response in Inflammatory Bowel Disease Patients.

Vedolizumab (VDZ) is used for treating inflammatory bowel disease (IBD) patients. A study investigating colonic epithelial barrier function ex vivo following VDZ is lacking. This work aims to evaluate ex vivo the colonic epithelial barrier function in IBD patients at baseline and during VDZ treatment, and to investigate the relationships between barrier function and clinical parameters. Colonic specimens were obtained from 23 IBD patients before, and at 24 and 52 weeks after VDZ treatment, and from 26 healthy volunteers (HV). Transepithelial electrical resistance (TEER, permeability to ions) and paracellular permeability were measured in Ussing chambers. IBD patients showed increased epithelial permeability to ions (TEER, 13.80 ± 1.04 Ω × cm2 vs. HV 20.70 ± 1.52 Ω × cm2, p < 0.001) without changes in paracellular permeability of a 4 kDa probe. VDZ increased TEER (18.09 ± 1.44 Ω × cm2, p < 0.001) after 52 weeks. A clinical response was observed in 58% and 25% of patients at week 24, and in 62% and 50% at week 52, in ulcerative colitis and Crohn's disease, respectively. Clinical and endoscopic scores were strongly associated with TEER. TEER < 14.65 Ω × cm2 predicted response to VDZ (OR 11; CI 2-59). VDZ reduces the increased permeability to ions observed in the colonic epithelium of IBD patients before treatment, in parallel to a clinical, histological (inflammatory infiltrate), and endoscopic improvement. A low TEER predicts clinical response to VDZ therapy.

Curcumin: a potential exogenous additive for the prevention of LPS-induced duck ileitis by the alleviation of inflammation and oxidative stress.

BACKGROUND: Lipopolysaccharides (LPS) are the main pathogenic substances in Gram-negative bacteria. The aim of this study was to investigate the preventive effects of dietary curcumin (CUR) on LPS toxicity in the duck ileum. The duck diet was supplemented with CUR (0.5 g kg-1 ) for 28 days, while the birds were injected with LPS (0.5 mg kg-1 body weight per injection, administered as seven injections in the last week of the experimental period). RESULTS: LPS significantly decreased the ileal villus-to-crypt ratio in the non-supplemented CUR group. Dietary CUR alleviated LPS-induced morphological damage to the ileum. Moreover, dietary CUR alleviated oxidative stress by increasing the levels of total superoxide dismutase (T-SOD) (P < 0.05) and glutathione S-transferase (GST) (P < 0.05) and decreasing the production of malonic dialdehyde (MDA) (P < 0.05) in control ducks and LPS-challenged ducks. Dietary CUR significantly inhibited the LPS-induced massive production of inflammatory factors (IL-1ß, IL-6, and TNF-α) (P < 0.05). CUR induced the inhibition of TLR4 and activation of Nrf2 to reduce the expression of inflammation-related genes (TLR4, NF-κB, IKK, TXNIP, NLRP3, caspase-1, IL-1ß, IL-6, and TNF-α). Moreover, dietary CUR ameliorated the decrease in claudin-1 and occludin expression (P < 0.05) and improved ZO-1 expression in the duck ileum (P < 0.05). CONCLUSION: In conclusion, dietary CUR has beneficial effects on LPS-induced ileal damage, oxidative damage, and inflammatory response by inhibiting the TLR/NF-κB and activating the Nrf2 signaling pathways in ducks. This study provides valuable information regarding the therapeutic uses of CUR in duck ileitis. © 2022 Society of Chemical Industry.

Duodenal Mucosal Barrier in Functional Dyspepsia.

BACKGROUND & AIMS: In addition to gastric sensorimotor dysfunctions, functional dyspepsia (FD) is also variably associated with duodenal micro-inflammation and epithelial barrier dysfunction, the pathogenesis and clinical significance of which are unknown. Our hypothesis was that miRNAs and/or inflammation degrade epithelial barrier proteins, resulting in increased duodenal mucosal permeability in FD. METHODS: We compared the duodenal mucosal gene expression and miRNAs, in vivo permeability (lactulose-mannitol excretion between 0 and 60 and 60 and 120 minutes after saccharide ingestion), ex vivo assessments (transmucosal resistance, fluorescein isothiocyanate [FITC]-dextran flux, and basal ion transport), and duodenal histology (light and electron microscopy) in 40 patients with FD and 24 controls. RESULTS: Compared with controls, the mRNA expression of several barrier proteins (zonula occludens-1, occludin, claudin-12, and E-cadherin) was modestly reduced (ie, a fold change of 0.8-0.85) in FD with increased expression of several miRNAs (eg, miR-142-3p and miR-144-3-p), which suppress these genes. The urinary lactulose excretion and the lactulose:mannitol ratio between 60 and 120 minutes were greater in FD than in controls (P < .05). The FITC-dextran flux, which reflects paracellular permeability, was inversely correlated (r = -0.32, P = .03) with transmucosal resistance and directly correlated (r = 0.4, P = .02) with lactulose:mannitol ratio. Other parameters (mucosal eosinophils, intraepithelial lymphocytes, and mast cells, transmucosal resistance, FITC-dextran flux, average intercellular distance, and proportion of dilated junctions) were not significantly different between groups. CONCLUSIONS: In FD, there is a modest reduction in the expression of several duodenal epithelial barrier proteins, which may be secondary to up-regulation of regulatory miRNAs, and increased small intestinal permeability measured in vivo.

Biomimetic and temporal-controlled nanocarriers with ileum transporter targeting for achieving oral administration of chemotherapeutic drugs.

BACKGROUND: Oral chemotherapy is preferred for patients with cancer owing to its multiple advantages, including convenience, better patient compliance, and improved safety. Nevertheless, various physical barriers exist in this route that hamper the development of oral chemotherapeutic formulations, including destruction of drugs in the gastrointestinal tract (GIT), low permeability in enterocytes, and short residence time in the intestine. To overcome these limitations, it is necessary to design an efficient oral drug delivery system with high efficacy and improved safety. RESULTS: Herein, we designed novel glycocholic acid (GCA)-functionalized double layer nanoparticles (GCA-NPs), which can act via an endogenous pathway and in a temporally controlled manner in the intestine, to enhance the oral bioavailability of hydrophobic chemotherapeutic drugs such as paclitaxel (PTX). GCA-NPs were composed of quercetin (Qu)-modified liposomes (QL) coated with GCA-chitosan oligosaccharide conjugate (GCOS). The GCA-NPs thus prepared showed prolonged intestinal retention time and good GIT stability due to the presence of chitosan oligosaccharide (COS) and enhanced active transportation via intestinal apical sodium-dependent bile acid transporter (ASBT) due to the presence of GCA. GCA-NPs also efficiently inhibited intestinal P-gp induced by Qu. PTX-loaded GCA-NPs (PTX@GCA-NPs) had a particle size of 84 nm and an entrapment efficiency of 98% with good stability. As a result, the oral bioavailability of PTX was increased 19-fold compared to that of oral Taxol® at the same dose. Oral PTX@GCA-NPs displayed superior antitumor efficacy and better safety than Taxol® when administered intravenously. CONCLUSIONS: Our novel drug delivery system showed remarkable efficacy in overcoming multiple limitations and is a promising carrier for oral delivery of multiple drugs, which addresses several challenges in oral delivery in the clinical context.

[Epithelial protective therapy in comorbid diseases. Practical Guidelines for Physicians].

This document was produced with the support of the National Medical Association for the Study of Comorbidities (NASС). In 2021 the first multidisciplinary National Consensus on the pathophysiological and clinical aspects of Increased Epithelial Permeability Syndrome was published. The proposed guidelines are developed on the basis of this Consensus, by the same team of experts. Twenty-eight Practical Guidelines for Physicians statements were adopted by the Expert Council using the "delphic" method. Such main groups of epithelial protective drugs as proton pump inhibitors, bismuth drugs and probiotics are discussed in these Guidelines from the positions of evidence-based medicine. The clinical and pharmacological characteristics of such a universal epithelial protector as rebamipide, acting at the preepithelial, epithelial and subepithelial levels, throughout gastrointestinal tract, are presented in detail.

Staphylococcus aureus enterotoxin B disrupts nasal epithelial barrier integrity.

BACKGROUND: Staphylococcus aureus colonization and release of enterotoxin B (SEB) has been associated with severe chronic rhinosinusitis with nasal polyps (CRSwNP). The pathogenic mechanism of SEB on epithelial barriers, however, is largely unexplored. OBJECTIVE: We investigated the effect of SEB on nasal epithelial barrier function. METHODS: SEB was apically administered to air-liquid interface (ALI) cultures of primary polyp and nasal epithelial cells of CRSwNP patients and healthy controls, respectively. Epithelial cell integrity and tight junction expression were evaluated. The involvement of Toll-like receptor 2 (TLR2) activation was studied in vitro with TLR2 monoclonal antibodies and in vivo in tlr2-/- knockout mice. RESULTS: SEB applied to ALI cultures of polyp epithelial cells decreased epithelial cell integrity by diminishing occludin and zonula occludens (ZO)-1 protein expression. Antagonizing TLR2 prevented SEB-induced barrier disruption. SEB applied in the nose of control mice increased mucosal permeability and decreased mRNA expression of occludin and ZO-1, whereas mucosal integrity and tight junction expression remained unaltered in tlr2-/- mice. Furthermore, in vitro SEB stimulation resulted in epithelial production of IL-6 and IL-8, which was prevented by TLR2 antagonization. CONCLUSION & CLINICAL RELEVANCE: SEB damages nasal polyp epithelial cell integrity by triggering TLR2 in CRSwNP. Our results suggest that SEB might represent a driving factor of disease exacerbation, rather than a causal factor for epithelial defects in CRSwNP. Interfering with TLR2 triggering might provide a way to avoid the pathophysiological consequences of S. aureus on inflammation in CRSwNP.

The tumor necrosis factor family molecules LIGHT and lymphotoxins in sinus mucosa of patients with chronic rhinosinusitis with or without nasal polyps.

BACKGROUND: Little is known about the role of lymphotoxins (LTs) family in the sinonasal mucosa of patients with chronic rhinosinusitis (CRS). This study aims at investigating the expression of LIGHT, LTα, LTß, and their receptors, LTßR and HVEM in normal and inflammatory sinus mucosa, and the effect of LIGHT and LTalpha1beta2 on chemokine secretion in epithelial cells, epithelial permeability, and leukocyte migration. MATERIAL AND METHODS: The expression of LTs family in sinonasal mucosa was evaluated with real-time PCR, immunohistochemistry, and western blot. In LTßR, HVEM siRNA, or control siRNA-transfected epithelial cells treated with LIGHT or LTalpha1beta2, the expression of chemokines, the epithelial permeability, and the expression of junctional complex proteins were evaluated using real-time PCR, ELISA, western blot, confocal microscopy, and FITC-dextran. In cultured endothelial cells treated with LIGHT or LTalpha1beta2, the expression of ICAM-1 and VCAM-1, and leukocyte migration were elucidated. RESULTS: LTs family was expressed in normal mucosa and their levels were increased in inflammatory mucosa of CRS patients. Recombinant LIGHT and LTalpha1beta2 induced chemokine secretion, increased epithelial permeability, and promoted leukocyte migration. However, the activity of LIGHT and LTalpha1beta2 was attenuated in cells transfected with LTßR and HVEM siRNA. CONCLUSIONS: LIGHT and LTs may participate in the ongoing process of chronic inflammation, inducing chemokine secretion, leukocyte migration, and dysregulated epithelial barrier through LTßR and HVEM in sinonasal mucosa.

Polarity scaffolds signaling in epithelial cell permeability.

As an integral part of the innate immune system, the epithelial membrane is exposed to an array of insults that may trigger an immune response. One of the immune system's main functions is to regulate the level of communications between the mucosa and the lumen of various tissues. While it is clear that inhaled or ingested substances, or microorganisms may induce changes that affect the epithelial barrier in various ways, the proteins involved in the signaling cascades and physiological events leading to the regulation and maintenance of the barrier are not always well characterized. We review here some of the signaling components involved in regulating the barrier's paracellular permeability, and their potential effects on the activation of an immune response. While an effective immune response must be launched against pathogenic insults, tolerance must also be maintained for non-pathogenic antigens such as those in the commensal flora or for endogenous metabolites. Along with other members of the innate and adaptive immunity, the endocannabinoid system also plays an instrumental role in maintaining the balance between inflammation and tolerance. We discuss the potential effects of endo- and phytocannabinoids on epithelial permeability and how the dysregulation of this system could be involved in diseases and targeted for therapy.

Response of Esophageal Epithelium to Acute and Chronic Stress in Rabbits.

We studied electrophysiological changes in rabbit esophageal epithelium following acute (AS) and chronic stress (CS). Esophageal tissue was placed in Ussing chamber and the potential difference U between the luminal and abluminal sides, the short-circuit current Isc, as well as the tissue resistance R were measured. The initial values of these parameters for each sample were determined after the samples were stabilized in Ringer solution. Then, the tissues were exposed for 1 h to normal Ringer solution or Ringer solution with pH 4.0 and pH 1.7 with or without pepsin (0.25 mg/ml). Fluorescein was added to the luminal side of the sample to measure its permeability. In the AS group, U at Ringer solution (pH 1.7)+pepsin was significantly decreased in comparison with the baseline and control values (by 46 and 22%, respectively, p<0.05). R decreased by 74% in comparison with baseline, which little differed from the decrease in control samples exposed to Ringer solution (pH 1.7)+pepsin (by 62%). CS did not change U relative to baseline values, while changes in R were similar to those in the AS group. In the AS group, the permeability of the esophageal tissue perfused with Ringer solution (pH 1.7)+pepsin was significantly higher than in both the control and CS groups. AS, but not CS, made the esophageal epithelium more sensitive to the effects of noxious agents, disrupted barrier properties, and increased permeability. The effects of stress on gastroesophageal reflux disease symptoms can be related to severe exposure to acid and/or pepsin; however, the mechanisms other than epithelial defense should be evaluated.

Piper Nigrum extract improves OVA-induced nasal epithelial barrier dysfunction via activating Nrf2/HO-1 signaling.

BACKGROUND: Piper nigrum L. (Piperaceae) is commonly used as a spice and traditional medicine in many countries. It has been reported to have anti-oxidant, anti-bacterial, anti-tumor, anti-mutagenic, anti-diabetic, and anti-inflammatory properties. However, the protective role of P. nigrum on epithelial function of upper respiratory tract injury in an allergic rhinitis (AR) mouse model has been unclear. This study aims to investigate the effects of P. nigrum fruit extract (PNE) on the nasal epithelial barrier function of the upper respiratory tract in an ovalbumin (OVA)-induced AR model. METHODS: AR mouse model was established by intraperitoneal injection with 200 µL saline containing 50 µg OVA adsorbed to 1 mg aluminum hydroxide, and intranasal challenge with 20 µL per nostril of 1 mg/ml OVA. Besides, mice were orally administrated once daily with PNE and dexamethasone (Dex) in 13 days. The nasal symptoms, inflammatory cells, OVA-specific immunoglobulins, cytokines, nasal histopathology, and immunohistochemistry were evaluated. RESULTS: The PNE oral administrations inhibited allergic responses via reduction of OVA-specific antibodies levels and mast cells histamine release, accordingly, the nasal symptoms in the early-phase reaction were also clearly ameliorated. In both nasal lavage fluid and nasal tissue, PNE suppressed the inflammatory cells accumulation, specifically with eosinophils. The intravenous Evans blue injection illustrated the epithelial permeability reduction of nasal mucosa layer in PNE-treated mice. Also; PNE treatments protected the epithelium integrity by preventing the epithelial shedding from nasal mucosa; as a result of enhancing the strong expression of the E-cadherin tight junction protein in cell-to-cell junctions, as well as inhibiting the degraded levels of zonula occludens-1 (ZO-1) and occludin into the nasal cavity. Additionally, PNE protected against nasal epithelial barrier dysfunction via enhancing the expression of Nrf2 activated form which led to increasing synthesis of the anti-inflammation enzyme HO-1. CONCLUSIONS: These obtained results suggest that PNE has a promising strategy for epithelial barrier stabilization in allergic rhinitis treatment.

Increased expression of interleukin 36 in chronic rhinosinusitis and its contribution to chemokine secretion and increased epithelial permeability.

BACKGROUND: IL-36 family, a recently reported member of the IL-1 cytokine family, plays an essential role in nonspecific innate immune response to infection. This study aims at investigating the expression of IL-36 family members (α, ß, and γ) in normal and inflammatory sinus mucosa of patients with chronic rhinosinusitis (CRS), their effects on chemokine secretion and on the barrier function of epithelial and endothelial cells, and the effect of Toll-like receptors on the expression of IL-36 in epithelial cells. MATERIAL AND METHODS: The expression of IL-36 family in normal and inflammatory sinus mucosa, the production of chemokines or the expression levels of IL-36 family in epithelial cells treated with IL-36 family members or stimulated with TLR3, TLR4, TLR5, or TLR7/8 agonists were measured with real time PCR, ELISA, immunohistochemistry, or Western blot. The epithelial and endothelial permeability, and transendothelial leukocyte migration were investigated using cultured epithelial and endothelial cells. RESULTS: IL-36α, IL-36ß, and IL-36γ were localized in epithelial cells of sinonasal mucosa. Their levels increased in inflammatory mucosa of CRS patients and are up-regulated by TLR3, TLR4, or TLR5 agonists. IL-36α, or IL-36γ induced CXCL1, CXCL2, and CXCL3 production. Epithelial and endothelial permeability, transendothelial leukocyte migration were increased in cells treated with IL-36α, IL-36ß, or IL-36γ. CONCLUSIONS: These results suggest that IL-36α, IL-36ß, and IL-36γ localized in superficial epithelium may act as a responder to microbial and nonmicrobial elements through TLR and subsequently produce CXC chemokines, playing an interplay between innate and adaptive immune response.

Airways exudation of plasma macromolecules: Innate defense, epithelial regeneration, and asthma.

This review discusses in vivo airway aspects of plasma exudation in relation to current views on epithelial permeability and epithelial regeneration in health and disease. Microvascular-epithelial exudation of bulk plasma proteins characteristically occurs in asthmatic patients, being especially pronounced in those with severe and exacerbating asthma. Healthy human and guinea pig airways challenged by noninjurious histamine-leukotriene-type autacoids also respond through prompt mucosal exudation of nonsieved plasma macromolecules. Contrary to current beliefs, epithelial permeability in the opposite direction (ie, absorption of inhaled molecules) has not been increased in patients with asthma and allergic rhinitis or in acutely exuding healthy airways. A slightly increased subepithelial hydrostatic pressure produces such unidirectional outward perviousness to macromolecules. Lack of increased absorption permeability in asthmatic patients can further be reconciled with occurrence of epithelial shedding, leaving small patches of denuded basement membrane. Counteracting escalating barrier breaks, plasma exudation promptly covers the denuded patches. Here it creates and sustains a biologically active barrier involving a neutrophil-rich, fibrin-fibronectin net. Furthermore, in the plasma-derived milieu, all epithelial cell types bordering the denuded patch dedifferentiate and migrate from all sides to cover the denuded basement membrane. However, this speedy epithelial regeneration can come at a cost. Guinea pig in vivo studies demonstrate that patches of epithelial denudation regeneration are exudation hot spots evoking asthma-like features, including recruitment/activation of granulocytes, proliferation of fibrocytes/smooth muscle cells, and basement membrane thickening. In conclusion, nonsieved plasma macromolecules can operate on the intact airway mucosa as potent components of first-line innate immunity responses. Exuded plasma also takes center stage in epithelial regeneration. When exaggerated, epithelial regeneration can contribute to the inception and development of asthma.

Gut Microbiota and Intestinal Trans-Epithelial Permeability.

Constant remodeling of tight junctions to regulate trans-epithelial permeability is essential in maintaining intestinal barrier functions and thus preventing diffusion of small molecules and bacteria to host systemic circulation. Gut microbiota dysbiosis and dysfunctional gut barrier have been correlated to a large number of diseases such as obesity, type 2 diabetes and inflammatory bowel disease. This led to the hypothesis that gut bacteria-epithelial cell interactions are key regulators of epithelial permeability through the modulation of tight junctions. Nevertheless, the molecular basis of host-pathogen interactions remains unclear mostly due to the inability of most in vitro models to recreate the differentiated tissue structure and components observed in the normal intestinal epithelium. Recent advances have led to the development of a novel cellular model derived from intestinal epithelial stem cells, the so-called organoids, encompassing all epithelial cell types and reproducing physiological properties of the intestinal tissue. We summarize herein knowledge on molecular aspects of intestinal barrier functions and the involvement of gut bacteria-epithelial cell interactions. This review also focuses on epithelial organoids as a promising model for epithelial barrier functions to study molecular aspects of gut microbiota-host interaction.

Increase in Epithelial Permeability and Cell Metabolism by High Mobility Group Box 1, Inflammatory Cytokines and TPEN in Caco-2 Cells as a Novel Model of Inflammatory Bowel Disease.

High mobility group box 1 protein (HMGB1) is involved in the pathogenesis of inflammatory bowel disease (IBD). Patients with IBD develop zinc deficiency. However, the detailed roles of HMGB1 and zinc deficiency in the intestinal epithelial barrier and cellular metabolism of IBD remain unknown. In the present study, Caco-2 cells in 2D culture and 2.5D Matrigel culture were pretreated with transforming growth factor-ß (TGF-ß) type 1 receptor kinase inhibitor EW-7197, epidermal growth factor receptor (EGFR) kinase inhibitor AG-1478 and a TNFα antibody before treatment with HMGB1 and inflammatory cytokines (TNFα and IFNγ). EW-7197, AG-1478 and the TNFα antibody prevented hyperpermeability induced by HMGB1 and inflammatory cytokines in 2.5D culture. HMGB1 affected cilia formation in 2.5D culture. EW-7197, AG-1478 and the TNFα antibody prevented the increase in cell metabolism induced by HMGB1 and inflammatory cytokines in 2D culture. Furthermore, ZnSO4 prevented the hyperpermeability induced by zinc chelator TPEN in 2.5D culture. ZnSO4 and TPEN induced cellular metabolism in 2D culture. The disruption of the epithelial barrier induced by HMGB1 and inflammatory cytokines contributed to TGF-ß/EGF signaling in Caco-2 cells. The TNFα antibody and ZnSO4 as well as EW-7197 and AG-1478 may have potential for use in therapy for IBD.

Neutrophil extracellular traps in nasal secretions of patients with stable and exacerbated chronic rhinosinusitis and their contribution to induce chemokine secretion and strengthen the epithelial barrier.

BACKGROUND: Neutrophil extracellular traps (NETs) participate in innate immunity by trapping microorganisms. Their pathophysiological implications have not been defined in chronic rhinosinusitis (CRS). OBJECTIVE: We investigated the presence of NETs in nasal secretion of patients with stable or exacerbated CRS and evaluated whether NETs participate in the secretion of chemokines in sinonasal epithelial cells, the epithelial permeability, and transendothelial leucocyte migration, and elucidate whether NETs are released by macrolides and dexamethasone. METHODS: The presence of NETs in nasal secretion and the release of NETs from neutrophils stimulated with macrolides or dexamethasone were evaluated by dsDNA Assay kit and fluorescence microscope. The chemokine secretion, epithelial permeability, and transendothelial leucocyte migration were measured in cultured cells incubated with NETs, the supernatant of unstimulated neutrophils (unstim), NETs inhibitor (DPI), or H3Cit, where the expression of junctional complex proteins and ICAM-1 was evaluated by real-time PCR, Western blots, and confocal microscope. RESULTS: The amount of NETs and NETs-forming neutrophils in nasal secretion increased in exacerbated CRS. Epithelial cells treated with NETs or H3Cit secreted chemokines and showed decreased permeability associated with up-regulated junctional complex proteins. Increased transendothelial leucocyte migration associated with up-regulated ICAM-1 was noted in endothelial cells treated with NETs or H3Cit. These findings were not found in cells treated with unstim, or DPI. NETs were released by macrolides, but not by dexamethasone. CONCLUSIONS AND CLINICAL RELEVANCE: NETs formation increased in exacerbated CRS, inducing chemokine secretion, strengthening the epithelial barrier, and promoting the neutrophils infiltration. Therefore, the release of NETs in CRS might be beneficial or detrimental to CRS patients.

Taurine administration prevents the intestine from the damage induced by beta-lactoglobulin sensitization in a murine model of food allergy.

BACKGROUND: Allergy to cow's milk proteins has often been associated with dysfunction of the intestinal mucosa caused by chronic inflammation in infants. This study evaluated the protective effect of taurine on intestinal damage induced by beta-lactoglobulin (ß-Lg) in Balb/c mice used as an animal model of allergy to cow's milk proteins. METHODS: Balb/c mice were treated with taurine administered orally by gavage (3mmol/kg/day) or intraperitoneally (100mg/kg/day) for two weeks, then sensitized intraperitoneally with ß-Lg. The electrophysiological parameters: active ion transport of chloride (Short-circuit current: Isc) and the passive ion permeability (Conductance: G) were measured ex vivo in Ussing chamber by intestine challenge with ß-Lg. Histological study was used to assess gut inflammation. Serum levels of TNF-α and IL-6 were measured. Serum IgG and IgE anti-ß-Lg were determined by ELISA. RESULTS: Compared with sensitized mice, ß-Lg challenge of intestinal epithelium of taurine-pre-treated mice in Ussing chamber did not influence the intensity of Isc, nor produce any changes in the G, reflecting a reduction in the secretory response and epithelial permeability. Histological and morphometric analysis showed that taurine reduced the intestinal damage and limited intestine retraction caused by ß-Lg sensitization. No statistically significant difference in the serum levels of TNF-α or IL-6 was found after oral or intraperitoneal administration of taurine. Treatment with taurine significantly decreased the IgG (p<0.001) and IgE anti ß-Lg levels (p<0.05). CONCLUSIONS: These results have for the first time provided evidence that pre-treatment with taurine appears to prevent intestinal damage induced by ß-Lg.

Eleutheroside B increase tight junction proteins and anti-inflammatory cytokines expression in intestinal porcine jejunum epithelial cells (IPEC-J2).

Eleutheroside B (EB) is a phenylpropanoid glycoside with anti-inflammatory properties, neuroprotective abilities, immunomodulatory effects, antinociceptive effects, and regulation of blood glucose. The aim of this study was to investigate the effects of EB on the barrier function in the intestinal porcine epithelial cells J2 (IPEC-J2). The IPEC-J2 cells were inoculated into 96-well plates at a density of 5 × 103 cells per well for 100% confluence. The cells were cultured in the presence of EB at concentrations of 0, 0.05, 0.10, and 0.20 mg/ml for 48 hr. Then, 0.10 mg/ml was selected as the suitable concentration for the estimation of transepithelial electric resistance (TEER) value, alkaline phosphatase activity, proinflammatory cytokines mRNA expression, tight junction mRNA and protein expression. The results of this study indicated that the supplementation of EB in IPEC-J2 cells decreased cellular membrane permeability and mRNA expression of proinflammatory cytokines, including interleukin-6 (IL-6), interferon-γ (INF-γ), and tumour necrosis factor-α (TNF-α). The supplementation of EB in IPEC-J2 cells increased tight junction protein expression and anti-inflammatory cytokines, interleukin 10 (IL-10) and transforming growth factor beta (TGF-ß). In addition, the western blotting and real-time quantitative polymerase chain reaction (RT-qPCR) results indicated that EB significantly (p < 0.05) increased the mRNA and protein expression of intestinal tight junction proteins, Claudin-3, Occludin, and Zonula Occludins protein-1 (ZO-1). Therefore, dietary supplementation of EB may increase intestinal barrier function, tight junction protein expression, anti-inflammatory cytokines, and decrease proinflammatory cytokines synthesis in IPEC-J2 cells.

Effects of human rhinovirus on epithelial barrier integrity and function in children with asthma.

BACKGROUND: Bronchial epithelial tight junctions (TJ) have been extensively assessed in healthy airway epithelium. However, no studies have yet assessed the effect of human rhinovirus (HRV) infection on the expression and resultant barrier function in epithelial tight junctions (TJ) in childhood asthma. OBJECTIVES: To investigate the impact of HRV infection on airway epithelial TJ expression and barrier function in airway epithelial cells (AECs) of children with and without asthma. Furthermore, to test the hypothesis that barrier integrity and function is compromised to a greater extent by HRV in AECs from asthmatic children. METHODS: Primary AECs were obtained from children with and without asthma, differentiated into air-liquid interface (ALI) cultures and infected with rhinovirus. Expression of claudin-1, occludin and zonula occluden-1 (ZO-1) was assessed via qPCR, immunocytochemistry (ICC), in-cell western (ICW) and confocal microscopy. Barrier function was assessed by transepithelial electrical resistance (TER; RT ) and permeability to fluorescent dextran. RESULTS: Basal TJ gene expression of claudin-1 and occludin was significantly upregulated in asthmatic children compared to non-asthmatics; however, no difference was seen with ZO-1. Interestingly, claudin-1, occludin and ZO-1 protein expression was significantly reduced in AEC of asthmatic children compared to non-asthmatic controls suggesting possible post-transcriptional inherent differences. HRV infection resulted in a transient dissociation of TJ and airway barrier integrity in non-asthmatic children. Although similar dissociation of TJ was observed in asthmatic children, a significant and sustained reduction in TJ expression concurrent with both a significant decrease in TER and an increase in permeability in asthmatic children was observed. CONCLUSION: This study demonstrates novel intrinsic differences in TJ gene and protein expression between AEC of children with and without asthma. Furthermore, it correlates directly the relationship between HRV infection and the resultant dissociation of epithelial TJ that causes a continued altered barrier function in children with asthma.