scholarly journals Barrier Protection and Recovery Effects of Gut Commensal Bacteria on Differentiated Intestinal Epithelial Cells In Vitro

Nutrients ◽  
2020 ◽  
Vol 12 (8) ◽  
pp. 2251
Author(s):  
Nooshin Mohebali ◽  
Katharina Ekat ◽  
Bernd Kreikemeyer ◽  
Anne Breitrück
Keyword(s):  
Intestinal Inflammation ◽  
Inflammatory Responses ◽  
Therapeutic Potential ◽  
Bacterial Species ◽  
Cell Monolayer ◽  
Commensal Bacteria ◽  
Epithelial Barrier ◽  
Inflammatory Stimulus ◽  
Monocyte Chemoattractant Protein 1

Alterations in the gut microbiota composition play a crucial role in the pathogenesis of inflammatory bowel disease (IBD) as specific commensal bacterial species are underrepresented in the microbiota of IBD patients. In this study, we examined the therapeutic potential of three commensal bacterial species, Faecalibacterium prausnitzii (F. prausnitzii), Roseburia intestinalis (R. intestinalis) and Bacteroides faecis (B. faecis) in an in vitro model of intestinal inflammation, by using differentiated Caco-2 and HT29-MTX cells, stimulated with a pro-inflammatory cocktail consisting of interleukin-1β (IL-1β), tumor necrosis factor-α (TNFα), interferon-γ (IFNγ), and lipopolysaccharide (LPS). Results obtained in this work demonstrated that all three bacterial species are able to recover the impairment of the epithelial barrier function induced by the inflammatory stimulus, as determined by an amelioration of the transepithelial electrical resistance (TEER) and the paracellular permeability of the cell monolayer. Moreover, inflammatory stimulus increased claudin-2 expression and decreased occludin expression were improved in the cells treated with commensal bacteria. Furthermore, the commensals were able to counteract the increased release of interleukin-8 (IL-8) and monocyte chemoattractant protein-1 (MCP-1) induced by the inflammatory stimulus. These findings indicated that F. prausnitzii, R. intestinalis and B. faecis improve the epithelial barrier integrity and limit inflammatory responses.

20 ELUCIDATING THE ROLE OF FUSOBACTERIUM NUCLEATUM IN INTESTINAL INFLAMMATION

2020 ◽  
Vol 26 (Supplement_1) ◽  
pp. S29-S29
Author(s):  
Melinda Engevik ◽  
Heather Danhof ◽  
Robert Britton ◽  
James Versalovic
Keyword(s):  
Immune Cell ◽  
Intestinal Inflammation ◽  
Inflammatory Responses ◽  
Bacterial Species ◽  
Fusobacterium Nucleatum ◽  
Outer Membrane Vesicles ◽  
Patient Treatment ◽  
Mucus Layer

Abstract Background While the direct cause of inflammatory bowel disease (IBD) is unknown, the gut microbiota is speculated to play a key role. The complexity of the microbiome has made it difficult to pinpoint whether bacterial species are specifically associated with IBD exacerbations; although select microbes have emerged as compelling candidates. Several groups have identified increased abundance in Fusobacterium in IBD patients. Fusobacterium nucleatum drives inflammation in the oral cavity, but few studies have examined the potential for F. nucleatum to promote intestinal inflammation. We hypothesize that F. nucleatum secretes Outer Membrane Vesicles (OMVs) that activate epithelial Toll-like receptor 4 (TLR4) to drive inflammation. Methods & Results Given the prevalence of F. nucleatum in IBD specimens, we sought to determine if this pathobiont could promote pro-inflammatory responses in human epithelial cultures. Using fluorescently tagged F. nucleatum, we demonstrate that F. nucleatum subspecies polymorphum adheres to the mucus layer of human colonic HT29-MTX cells. Application of F. nucleatum metabolites to HT29-MTX cells resulted in upregulation of pro-inflammatory cytokines IL-8 and TNF by qPCR and ELISA. Purified OMVs from F. nucleatum alone were able to stimulate IL-8 and TNF production. This demonstrates the robust response of colonic epithelial cells to F. nucleatum. Additionally, we used human jejunum and colon enteroid monolayers treated with F. nucleatum metabolites in an anti-oxidant free enteroid media and found that F. nucleatum secreted products promoted TNF secretion by ELISA. Using the Luminex Magpix Platform we further queried the enteroid system to assess which pathways were activated. Enteroid monolayers treated with F. nucleatum metabolites exhibited increased phosphorylated ERK and CREB, downstream effectors of TLRs. We next sought to address whether F. nucleatum alone could elicit pro-inflammatory responses in a mouse model. Mice harboring a human microbiota, or humanized mice, were treated for 5 days with a cocktail of antibiotics and treated with F. nucleatum (108 CFU) by oral gavage; a regimen designed to mimic IBD patient treatment. Compared to control mice that received antibiotics and PBS vehicle control, mice treated with F. nucleatum exhibited disruption of the colonic architecture, with increased immune infiltrate and depleted mucus layer, resulting in a closer proximity of luminal contents to the epithelium. Analysis of mucosal gene expression revealed increased levels of epithelial TNF and KC (mouse homolog of IL-8), in addition to immune cell derived IL-6 in F. nucleatum-treated mice compared for controls. Conclusions These data provide evidence that F. nucleatum is capable of driving a pro-inflammatory signaling cascade in vitro and in vivo and F. nucleatum may represent a specific target for drug therapy.

scholarly journals The Inflammatory Role of Pro-Resolving Mediators in Endometriosis: An Integrative Review

2021 ◽  
Vol 22 (9) ◽  
pp. 4370
Author(s):  
Cássia de Fáveri ◽  
Paula M. Poeta Fermino ◽  
Anna P. Piovezan ◽  
Lia K. Volpato
Keyword(s):  
Intracellular Signaling ◽  
Inflammatory Responses ◽  
Therapeutic Potential ◽  
Critical Role ◽  
Integrative Review ◽  
Inflammatory Factors ◽  
Resolvin D1 ◽  
Endogenous Factors

The pathogenesis of endometriosis is still controversial, although it is known that the inflammatory immune response plays a critical role in this process. The resolution of inflammation is an active process where the activation of endogenous factors allows the host tissue to maintain homeostasis. The mechanisms by which pro-resolving mediators (PRM) act in endometriosis are still little explored. Thus, this integrative review aims to synthesize the available content regarding the role of PRM in endometriosis. Experimental and in vitro studies with Lipoxin A4 demonstrate a potential inhibitory effect on endometrial lesions’ progression, attenuating pro-inflammatory and angiogenic signals, inhibiting proliferative and invasive action suppressing intracellular signaling induced by cytokines and estradiol, mainly through the FPR2/ALX. Investigations with Resolvin D1 demonstrated the inhibition of endometrial lesions and decreased pro-inflammatory factors. Annexin A1 is expressed in the endometrium and is specifically present in women with endometriosis, although the available studies are still inconsistent. Thus, we believe there is a gap in knowledge regarding the PRM pathways in patients with endometriosis. It is important to note that these substances’ therapeutic potential is evident since the immune and abnormal inflammatory responses play an essential role in endometriosis development and progression.

scholarly journals In Vitro Evaluation of the Anti-Inflammatory Effect of KMUP-1 and in Vivo Analysis of Its Therapeutic Potential in Osteoarthritis

Biomedicines ◽  
2021 ◽  
Vol 9 (6) ◽  
pp. 615
Author(s):  
Shang-En Huang ◽  
Erna Sulistyowati ◽  
Yu-Ying Chao ◽  
Bin-Nan Wu ◽  
Zen-Kong Dai ◽  
...  
Keyword(s):  
Articular Cartilage ◽  
Inflammatory Responses ◽  
Therapeutic Potential ◽  
Antioxidant Properties ◽  
Serum Levels ◽  
Gene Expressions ◽  
Tnf Α ◽  
Anti Inflammatory

Osteoarthritis is a degenerative arthropathy that is mainly characterized by dysregulation of inflammatory responses. KMUP-1, a derived chemical synthetic of xanthine, has been shown to have anti-inflammatory and antioxidant properties. Here, we aimed to investigate the in vitro anti-inflammatory and in vivo anti-osteoarthritis effects of KMUP-1. Protein and gene expressions of inflammation markers were determined by ELISA, Western blotting and microarray, respectively. RAW264.7 mouse macrophages were cultured and pretreated with KMUP-1 (1, 5, 10 μM). The productions of TNF-α, IL-6, MMP-2 and MMP- 9 were reduced by KMUP-1 pretreatment in LPS-induced inflammation of RAW264.7 cells. The expressions of iNOS, TNF-α, COX-2, MMP-2 and MMP-9 were also inhibited by KMUP-1 pretreatment. The gene expression levels of TNF and COX families were also downregulated. In addition, KMUP-1 suppressed the activations of ERK, JNK and p38 as well as phosphorylation of IκBα/NF-κB signaling pathways. Furthermore, SIRT1 inhibitor attenuated the inhibitory effect of KMUP-1 in LPS-induced NF-κB activation. In vivo study showed that KMUP-1 reduced mechanical hyperalgesia in monoiodoacetic acid (MIA)-induced rats OA. Additionally, KMUP-1 pretreatment reduced the serum levels of TNF-α and IL-6 in MIA-injected rats. Moreover, macroscopic and histological observation showed that KMUP-1 reduced articular cartilage erosion in rats. Our results demonstrated that KMUP-1 inhibited the inflammatory responses and restored SIRT1 in vitro, alleviated joint-related pain and cartilage destruction in vivo. Taken together, KMUP-1 has the potential to improve MIA-induced articular cartilage degradation by inhibiting the levels and expression of inflammatory mediators suggesting that KMUP-1 might be a potential therapeutic agent for OA.

scholarly journals A Salmonella Virulence Factor Activates the NOD1/NOD2 Signaling Pathway

mBio ◽  
2011 ◽  
Vol 2 (6) ◽  
Author(s):  
A. Marijke Keestra ◽  
Maria G. Winter ◽  
Daisy Klein-Douwel ◽  
Mariana N. Xavier ◽  
Sebastian E. Winter ◽  
...  
Keyword(s):  
Signaling Pathway ◽  
Type Iii Secretion ◽  
Salmonella Enterica ◽  
Intestinal Inflammation ◽  
Inflammatory Responses ◽  
Type Iii Secretion System ◽  
Secretion System ◽  
Content Type ◽  
Type Iii

ABSTRACTThe invasion-associated type III secretion system (T3SS-1) ofSalmonella entericaserotype Typhimurium (S. Typhimurium) activates the transcription factor NF-κB in tissue culture cells and induces inflammatory responses in animal models through unknown mechanisms. Here we show that bacterial delivery or ectopic expression of SipA, a T3SS-1-translocated protein, led to the activation of the NOD1/NOD2 signaling pathway and consequent RIP2-mediated induction of NF-κB-dependent inflammatory responses. SipA-mediated activation of NOD1/NOD2 signaling was independent of bacterial invasionin vitrobut required an intact T3SS-1. In the mouse colitis model, SipA triggered mucosal inflammation in wild-type mice but not in NOD1/NOD2-deficient mice. These findings implicate SipA-driven activation of the NOD1/NOD2 signaling pathway as a mechanism by which the T3SS-1 induces inflammatory responsesin vitroandin vivo.IMPORTANCESalmonella entericaserotype Typhimurium (S. Typhimurium) deploys a type III secretion system (T3SS-1) to induce intestinal inflammation and benefits from the ensuing host response, which enhances growth of the pathogen in the intestinal lumen. However, the mechanisms by which the T3SS-1 triggers inflammatory responses have not been resolved. Here we show that the T3SS-1 effector protein SipA induces NF-κB activation and intestinal inflammation by activating the NOD1/NOD2 signaling pathway. These data suggest that the T3SS-1 escalates innate responses through a SipA-mediated activation of pattern recognition receptors in the host cell cytosol.

A dual-action peptide-containing hydrogel targets wound infection and inflammation

2020 ◽  
Vol 12 (524) ◽  
pp. eaax6601 ◽  
Author(s):  
Manoj Puthia ◽  
Marta Butrym ◽  
Jitka Petrlova ◽  
Ann-Charlotte Strömdahl ◽  
Madelene Å. Andersson ◽  
...  
Keyword(s):  
Conformational Changes ◽  
Inflammatory Responses ◽  
Therapeutic Potential ◽  
Nuclear Factor Κb ◽  
Reporter Mice ◽  
Dual Action ◽  
Infection And Inflammation ◽  
Molecular Patterns

There is a clinical need for improved wound treatments that prevent both infection and excessive inflammation. TCP-25, a thrombin-derived peptide, is antibacterial and scavenges pathogen-associated molecular patterns (PAMPs), such as lipopolysaccharide, thereby preventing CD14 interaction and Toll-like receptor dimerization, leading to reduced downstream immune activation. Here, we describe the development of a hydrogel formulation that was functionalized with TCP-25 to target bacteria and associated PAMP-induced inflammation. In vitro studies determined the polymer prerequisites for such TCP-25–mediated dual action, favoring the use of noncharged hydrophilic hydrogels, which enabled peptide conformational changes and LPS binding. The TCP-25–functionalized hydrogels killed Gram-positive Staphylococcus aureus and Gram-negative Pseudomonas aeruginosa bacteria in vitro, as well as in experimental mouse models of subcutaneous infection. The TCP-25 hydrogel also mediated reduction of LPS-induced local inflammatory responses, as demonstrated by analysis of local cytokine production and in vivo bioimaging using nuclear factor κB (NF-κB) reporter mice. In porcine partial thickness wound models, TCP-25 prevented infection with S. aureus and reduced concentrations of proinflammatory cytokines. Proteolytic fragmentation of TCP-25 in vitro yielded a series of bioactive TCP fragments that were identical or similar to those present in wounds in vivo. Together, the results demonstrate the therapeutic potential of TCP-25 hydrogel, a wound treatment based on the body’s peptide defense, for prevention of both bacterial infection and the accompanying inflammation.

scholarly journals Safety and Utility of Chloroquine/ Hydroxychloroquine in Palliative Care Patients

2020 ◽  
pp. 104990912095277
Author(s):  
Eric Prommer
Keyword(s):  
Palliative Care ◽  
Inflammatory Responses ◽  
Therapeutic Potential ◽  
Symptom Control ◽  
In Vivo Studies ◽  
Advanced Illness ◽  
Know How ◽  
Seriously Ill

The coronavirus disease 2019 (COVID-19) pandemic represents a significant healthcare challenge for the world. Many drugs have therapeutic potential. The aminoquinolones, hydroxychloroquine, and chloroquine are undergoing evaluation as a potential therapy against COVID -19. In vitro and in vivo studies suggest that these drugs affect viral adherence and modify inflammatory responses, which may provide some impact on the symptoms associated with COVID. As palliative care specialists encounter more COVID positive patients, palliative care specialists need to know how these drugs work, and importantly how they interact with palliative care drugs used for symptom control. At the same time, there is a need to reduce polypharmacy in any seriously ill patient population. The goals of this paper are to identify whether or not hydroxychloroquine/chloroquine improves symptoms in palliative care patients and whether or not these drugs are safe to use in the advanced illness population who have COVID.

scholarly journals Role of JAM-A tyrosine phosphorylation in epithelial barrier dysfunction during intestinal inflammation

2019 ◽  
Vol 30 (5) ◽  
pp. 566-578 ◽  
Author(s):  
Shuling Fan ◽  
Caroline M. Weight ◽  
Anny-Claude Luissint ◽  
Roland S. Hilgarth ◽  
Jennifer C. Brazil ◽  
...  
Keyword(s):  
Tyrosine Phosphorylation ◽  
Barrier Function ◽  
Intestinal Inflammation ◽  
Kinase Inhibitor ◽  
Src Kinase ◽  
Small Gtpase ◽  
Epithelial Barrier ◽  
Barrier Dysfunction ◽  
Junction Protein

Junctional adhesion molecule-A (JAM-A), an epithelial tight junction protein, plays an important role in regulating intestinal permeability through association with a scaffold signaling complex containing ZO-2, Afadin, and the small GTPase Rap2. Under inflammatory conditions, we report that the cytoplasmic tail of JAM-A is tyrosine phosphorylated (p-Y280) in association with loss of barrier function. While barely detectable Y280 phosphorylation was observed in confluent monolayers of human intestinal epithelial cells under basal conditions, exposure to cytokines TNFα, IFNγ, IL-22, or IL-17A, resulted in compromised barrier function in parallel with increased p-Y280. Phosphorylation was Src kinase dependent, and we identified Yes-1 and PTPN13 as a major kinase and phosphatase for p-JAM-A Y280, respectively. Moreover, cytokines IL-22 or IL-17A induced increased activity of Yes-1. Furthermore, the Src kinase inhibitor PP2 rescued cytokine-induced epithelial barrier defects and inhibited phosphorylation of JAM-A Y280 in vitro. Phosphorylation of JAM-A Y280 and increased permeability correlated with reduced JAM-A association with active Rap2. Finally, we observed increased phosphorylation of Y280 in colonic epithelium of individuals with ulcerative colitis and in mice with experimentally induced colitis. These findings support a novel mechanism by which tyrosine phosphorylation of JAM-A Y280 regulates epithelial barrier function during inflammation.

scholarly journals Comparison of the Inflammatory Responses of Human Meningeal Cells following Challenge with Neisseria lactamica and with Neisseria meningitidis

2006 ◽  
Vol 74 (11) ◽  
pp. 6467-6478 ◽  
Author(s):  
Mark I. Fowler ◽  
Kiave Y. Ho Wang Yin ◽  
Holly E. Humphries ◽  
John E. Heckels ◽  
Myron Christodoulides
Keyword(s):  
Neisseria Meningitidis ◽  
Inflammatory Responses ◽  
Host Cells ◽  
Pathogenic Potential ◽  
Monocyte Chemoattractant Protein 1 ◽  
Gm Csf ◽  
Neisseria Lactamica ◽  
Meningeal Cells ◽  
Macrophage Colony

ABSTRACT The rationale for the present study was to determine how different species of bacteria interact with cells of the human meninges in order to gain information that would have broad relevance to understanding aspects of the innate immune response in the brain. Neisseria lactamica is an occasional cause of meningitis in humans, and in this study we investigated the in vitro interactions between N. lactamica and cells derived from the leptomeninges in comparison with the closely related organism Neisseria meningitidis, a major cause of meningitis worldwide. N. lactamica adhered specifically to meningioma cells, but the levels of adherence were generally lower than those with N. meningitidis. Meningioma cells challenged with N. lactamica and N. meningitidis secreted significant amounts of the proinflammatory cytokine interleukin-6 (IL-6), the C-X-C chemokine IL-8, and the C-C chemokines monocyte chemoattractant protein 1 (MCP-1) and RANTES, but it secreted very low levels of the cytokine growth factor granulocyte-macrophage colony-stimulating factor (GM-CSF). Thus, meningeal cells are involved in the innate host response to Neisseria species that are capable of entering the cerebrospinal fluid. The levels of IL-8 and MCP-1 secretion induced by both bacteria were essentially similar. By contrast, N. lactamica induced significantly lower levels of IL-6 than N. meningitidis. Challenge with the highest concentration of N. lactamica (108 CFU) induced a small but significant down-regulation of RANTES secretion, which was not observed with lower concentrations of bacteria. N. meningitidis (106 to 108 CFU) also down-regulated RANTES secretion, but this effect was significantly greater than that observed with N. lactamica. Although both bacteria were unable to invade meningeal cells directly, host cells remained viable on prolonged challenge with N. lactamica, whereas N. meningitidis induced death; the mechanism was overwhelming necrosis with no significant apoptosis. It is likely that differential expression of modulins between N. lactamica and N. meningitidis contributes to these observed differences in pathogenic potential.

scholarly journals The phytonutrient cinnamaldehyde limits intestinal inflammation and enteric parasite infection

2021 ◽  
Author(s):  
Ling Zhu ◽  
Audrey I.S. Andersen-Civil ◽  
Laura J. Myhill ◽  
Stig M. Thamsborg ◽  
Witold Kot ◽  
...  
Keyword(s):  
Gut Microbiota ◽  
Metabolic Diseases ◽  
Intestinal Inflammation ◽  
Inflammatory Responses ◽  
Host Responses ◽  
Mucosal Inflammation ◽  
Enteric Infection ◽  
Intestinal Epithelial ◽  
Mesenteric Lymph Nodes

AbstractPhytonutrients such as cinnamaldehyde (CA) have been studied for their effects on metabolic diseases, but their influence on mucosal inflammation and immunity to enteric infection are not well documented. Here, we show that consumption of CA significantly down-regulates transcriptional pathways connected to inflammation in the small intestine of mice. During infection with the enteric helminth Heligomosomoides polygyrus, CA-treated mice displayed higher growth rates and less worms, concomitant with altered T-cell populations in mesenteric lymph nodes. Furthermore, infection-induced changes in gene pathways connected to cell cycle and mitotic activity were counteracted by CA. Mechanically, CA did not appear to exert activity through a prebiotic effect, as CA treatment did not significantly change the composition of the gut microbiota. Instead, in vitro experiments showed that CA directly induced xenobiotic metabolizing pathways in intestinal epithelial cells and suppressed endotoxin-induced inflammatory responses in macrophages. Thus, CA down-regulates inflammatory pathways in the intestinal mucosa and regulates host responses to enteric infection. These properties appear to be largely independent of the gut microbiota and instead connected to CA’s ability to induce antioxidant pathways in intestinal cells. Our results encourage further investigation into the use of CA and related phytonutrients as functional food components to promote intestinal health in humans and animals.

scholarly journals KCNN4 Expression Is Elevated in Inflammatory Bowel Disease: This Might Be a Novel Marker and Therapeutic Option Targeting Potassium Channels

2020 ◽  
Vol 29 (4) ◽  
pp. 539-547
Author(s):  
Christoph Süss ◽  
Lucile Broncy ◽  
Kirstin Pollinger ◽  
Claudia Kunst ◽  
Karsten Gülow ◽  
...  
Keyword(s):  
Therapeutic Target ◽  
Inflammatory Diseases ◽  
Therapeutic Option ◽  
Cell Monolayer ◽  
Secretory Diarrhea ◽  
K Channel ◽  
Epithelial Barrier ◽  
Mrna Levels ◽  
Inflammatory Bowel

Background and Aims: The K + channel KCNN4 is involved in many inflammatory diseases. Previous work has shown that this channel is involved in epithelial ion transport and intestinal restitution. In inflammatory bowel diseases (IBD) a defective epithelial barrier can lead to typical symptoms like secretory diarrhea and the formation of intestinal ulcers. We compared surgical samples from patients with IBD, diverticulitis and controls without inflammation to determine the potential role of KCNN4 as a diagnostic marker and/or therapeutic target. Methods: mRNA-levels of KCNN4 and a control K + channel were determined in intestinal epithelial cells (IEC) from patients with IBD, diverticulitis and controls. In addition, we performed a Western blot analysis of KCNN4 and a respective control K + channel in IEC from patients with IBD. Furthermore, we determined epithelial barrier integrity by measuring the flux of fluorescent-labeled dextran beads across a cell monolayer upon incubation with interferon-γ. Results: KCNN4 mRNA and protein levels were elevated in IEC from patients with Crohn`s disease (CD) and ulcerative colitis (UC). Of note, KCNN4 was not elevated in non-IBD intestinal inflammatory conditions e.g. diverticulitis. Of clinical relevance, pharmacological KCNN4 channel openers stabilized epithelial barrier function in vitro. Thus, KCNN4 may have a protective role in IBD and constitute a therapeutic target. Conclusions: Our data demonstrate elevated KCNN4 both at mRNA and protein level in IEC specifically from patients with IBD. Therefore, we conclude that KCNN4 could be used as a novel marker for IBD, especially for the establishment of initial diagnosis. Of therapeutic consequence, we show that pharmacological KCNN4 openers stabilize the epithelial barrier. Thus, KCNN4 might be a novel target to diagnose and treat IBD.

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