Alleviation of Intestinal Inflammation by Dietary Pomegranate Extract Supplementation in Mice

Abstract Objectives Inflammatory bowel disease (IBD) results from a complex interaction among host, microbial and environmental factors. Among these, diet has emerged as an important and actionable modifier of IBD activity. Pomegranate major bioactive metabolites, ellagic acid and urolithins, have been shown to improve symptoms of IBD in chemically induced mouse models of colitis. Here, we aim to test the hypothesis that dietary pomegranate extract (PomX) supplementation will reduce the development of colitis in IL-10 knock out (IL-10−/−) mice, which spontaneously develop chronic colitis after birth. Methods 4 week old male IL-10−/− mice were randomly assigned to a high fat high sucrose (HFHS) diet, or to a HFHS diet supplemented with 0.25% PomX for 8 weeks. At the end of the experiment, the mice were euthanized and intestinal tissues were isolated and frozen for RNA extraction, or fixed for histologic analysis. Plasma samples were collected and processed for lipocalin 2 assay. Results Histomorphological analysis of colonic tissues revealed lower histological scores in HFHS-PomX fed mice, 3.9 ± 1.0 vs. 2.6 ± 0.5 in HFHS fed mice (n = 8, P = 0.02). In addition, signs of rectal prolapse were observed in 62.5% of IL-10−/− mice in the HFHS group vs. 12.5% in the HFHS/PomX group (P = 0.04). RNAseq and bioinformatic analysis, obtained from the colonic tissues (n = 4 mice/each group), showed in PomX treated mice a downregulation of 483 genes and an upregulation of 263 genes. Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) and Reactome analyses showed that PomX downregulated genes which are mainly associated with immune inflammatory responses, defenses, and neutrophil degranulation, including IL1α, IL6 and TNFα pro-inflammatory cytokines. Spleen weights were lower in HFHS-PomX treated mice as compared to HFHS fed control mice (P = 0.04). In addition, PomX treated mice showed a trend of higher body weights (∼13%) and lower lipocalin 2 plasma levels (∼46%) as compared to HFHS fed mice. Conclusions Our data demonstrated that PomX supplementation decreased colitis symptoms and lowered the inflammatory parameters of colitis in HFHS fed IL10−/− mice. These data support the anti-inflammatory effects of dietary PomX supplementation that were previously observed in the DSS colitis murine model. Funding Sources This project was supported by UCLA Center for Human Nutrition.

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Transplantation of bacteriophages from ulcerative colitis patients shifts the gut bacteriome and exacerbates severity of DSS-colitis

10.1101/2021.09.10.459444 ◽

2021 ◽

Author(s):

Anshul Sinha ◽

Yue Li ◽

Mohammadali Khan Mirzaei ◽

Michael Shamash ◽

Rana Samadfam ◽

...

Keyword(s):

Ulcerative Colitis ◽

Bacterial Diversity ◽

Bacterial Communities ◽

Intestinal Inflammation ◽

Inflammatory Responses ◽

Experimental Colitis ◽

Shotgun Metagenomics ◽

Dss Colitis ◽

Bowel Diseases

Inflammatory bowel diseases (IBDs) including Crohn's disease (CD) and ulcerative colitis (UC) are characterized by chronic and debilitating gut inflammation. Altered bacterial communities of the intestine are strongly associated with IBD initiation and progression. The gut virome, which is primarily composed of bacterial viruses (bacteriophages, phages) is thought to be an important factor regulating and shaping microbial communities in the gut. While alterations in the gut virome have been observed in IBD patients, the contribution of these viruses to alterations in the bacterial community and heightened inflammatory responses associated with IBD patients remains largely unknown. Here, we performed in vivo microbial cross-infection experiments to follow the effects of fecal virus-like particles (VLPs) isolated from UC patients and healthy controls on bacterial diversity and severity of experimental colitis in human microbiota-associated (HMA) mice. Shotgun metagenomics confirmed that several phages were transferred to HMA mice, resulting in treatment-specific alterations in the gut virome. VLPs from healthy and UC patients also shifted gut bacterial diversity of these mice, an effect that was amplified during experimental colitis. VLPs isolated from UC patients specifically altered the relative abundance of several bacterial taxa previously implicated in IBD progression. Additionally, UC VLP administration heightened colitis severity in HMA mice, as indicated by shortened colon length and increased pro-inflammatory cytokine production. Importantly, this effect was dependent on intact VLPs. Our findings build on recent literature indicating that phages are dynamic regulators of bacterial communities in the gut and implicate the intestinal virome in modulating intestinal inflammation and disease.

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A36 THE ROLE OF MICROBIAL INDOLE METABOLITES IN CONTROLLING INFLAMMATORY RESPONSES AND HEALING IN RESPONSE TO DSS-INDUCED COLITIS

Journal of the Canadian Association of Gastroenterology ◽

10.1093/jcag/gwz047.035 ◽

2020 ◽

Vol 3 (Supplement_1) ◽

pp. 43-44

Author(s):

K Nieves ◽

K L Flannigan ◽

L Alston ◽

C Thomson ◽

K McCoy ◽

...

Keyword(s):

Immune Cell ◽

Intestinal Inflammation ◽

Inflammatory Responses ◽

Pregnane X Receptor ◽

Lipocalin 2 ◽

Mortality And Morbidity ◽

Microbial Metabolite ◽

Specific Pathogen ◽

Mucosal Homeostasis ◽

Xenobiotic Receptor

Abstract Background Failure to resolve inflammation is often associate with the complications of Crohn’s Disease (CD). The pregnane X receptor (PXR), a xenobiotic receptor, is recognized for its role in suppressing inflammation and has recently been shown to influence fibrogenesis in the liver. In the intestine, PXR-signaling can be influenced by the microbial tryptophan metabolite indole-3- propionic acid (IPA), which can modulate intestinal inflammation, in turn influencing fibrogenesis, resolution and healing. This suggests that the gut microbiota could modulate mucosal homeostasis and resolution of inflammation via microbial metabolites Aims To understand and characterize the interplay between microbial complexity and the regulation of host inflammatory and healing responses, specifically focusing on the PXR and its microbial metabolite ligand IPA. Methods Intestinal inflammation was induced using DSS (1%, 1.5%, 2% and 3.5%) for 5 days followed by healing for 25 days in C57Bl/6 stably derived moderately diverse mouse microbiota 2 (sDMDMm2) colonized gnotobiotic and C57Bl/6 specific pathogen free (SPF) mice. Inflammation, architectural changes and fibrosis were assessed using Haemotoxylin and Eosin and Masson-Trichrome histological stains. Weight was recorded daily for the first 10 days and every other day after for 25 days, for a total of 30 days. Fecal lipocalin was quantified in samples collected throughout the study to assess inflammation. Innate immune cell influx was measured by flow cytometry, and the microbiota assessed via 16S rRNA sequencing. Results The gnotobiotic sDMDMm2 mice were exquisitely sensitive to DSS-induced colitis, exhibiting significantly increased mortality and morbidity at 2% and 3.5% w/v DSS compared to the SPF group. To elicit the same degree of disease to assess recovery, sDMDMm2 mice were exposed to 1.5% DSS and SPF mice to 3.5% DSS. Following 25 days recovery, sDMDMm2 colonized mice showed increased levels of fecal lipocalin 2, as compared to the SPF mice. DSS-treated sDMDMm2 mice supplemented with IPA during their recovery presented lower levels of fecal lipocalin, similar to colitic SPF mice. IPA supplemented sDMDMm2 mice also exhibited greater overall survival, with no significant differences in neutrophil count compared to mice given H20 during recovery. Conclusions A model system with a less complex microbiota (sDMDMm2) has a higher susceptibility to acute inflammation and a diminished capacity to resolve said inflammation. Addition of the microbial metabolite IPA normalized the recovery of the sDMDMm2 colonized mice, to a response indistinguishable from SPF mice, while also increasing survival. These data highlight the importance of microbial complexity in the regulation of intestinal mucosal homeostasis. Funding Agencies CAG, CCC, CIHR

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MyD88 adaptor-like (Mal) regulates intestinal homeostasis and colitis-associated colorectal cancer in mice

AJP Gastrointestinal and Liver Physiology ◽

10.1152/ajpgi.00399.2013 ◽

2014 ◽

Vol 306 (9) ◽

pp. G769-G778 ◽

Cited By ~ 17

Author(s):

Gabriella Aviello ◽

Sinéad C. Corr ◽

Daniel G. W. Johnston ◽

Luke A. J. O'Neill ◽

Padraic G. Fallon

Keyword(s):

Bone Marrow ◽

Intestinal Inflammation ◽

Inflammatory Responses ◽

Bone Marrow Cells ◽

Protective Role ◽

Microbial Pathogens ◽

Intestinal Homeostasis ◽

Dss Colitis ◽

Recognition And Response ◽

Chronic Intestinal Inflammation

Toll-like receptors (TLRs) play a central role in the recognition and response to microbial pathogens and in the maintenance and function of the epithelial barrier integrity in the gut. The protein MyD88 adaptor-like (Mal/TIRAP) serves as a bridge between TLR2/TLR4- and MyD88-mediated signaling to orchestrate downstream inflammatory responses. Whereas MyD88 has an essential function in the maintenance of intestinal homeostasis, a role for Mal in this context is less well described. Colitis was induced in wild-type (WT) and Mal-deficient ( Mal −/−) mice by administration of dextran sodium sulfate (DSS). Colitis-associated cancer was induced by DSS and azoxymethane (AOM) treatment. Chimeric mice were generated by total body gamma irradiation followed by transplantation of bone marrow cells. In the DSS model of colon epithelial injury, Mal −/− mice developed increased inflammation and severity of colitis relative to WT mice. Mal −/− mice demonstrated the presence of inflammatory cell infiltrates, increased crypt proliferation, and presence of neoformations. Furthermore, in the AOM/DSS model, Mal −/− mice had greater incidence of tumors. Mal −/− and WT bone marrow chimeras demonstrated that nonhematopoietic cell expression of Mal had an important protective role in the control of intestinal inflammation and inflammation-associated cancer. Mal is essential for the maintenance of intestinal homeostasis and expression of Mal in nonhematopoietic cells prevents chronic intestinal inflammation that may predispose to colon neoplasia.

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Der Knock out der c-Jun N-terminalen Kinase 2 (JNK2) erhöht Krankheitsaktivität und Mortalität in der chronischen DSS-Colitis

Zeitschrift für Gastroenterologie ◽

10.1055/s-2006-950642 ◽

2006 ◽

Vol 44 (08) ◽

Author(s):

AM Chromik ◽

AM Müller ◽

M Albrecht ◽

S Rottmann ◽

MH Seelig ◽

...

Keyword(s):

Knock Out ◽

Dss Colitis

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The Immunomodulatory Role of G2013 (α-L-Guluronic Acid) on the Expression of TLR2 and TLR4 in HT29 cell line

Current Drug Discovery Technologies ◽

10.2174/1570163815666180226093711 ◽

2019 ◽

Vol 16 (1) ◽

pp. 91-95 ◽

Cited By ~ 4

Author(s):

Hamid Farhang ◽

Laleh Sharifi ◽

Mohammad Mehdi Soltan Dallal ◽

Mona Moshiri ◽

Zahra Norouzbabaie ◽

...

Keyword(s):

Inflammatory Responses ◽

Inflammatory Diseases ◽

Rna Extraction ◽

Cell Plate ◽

Inhibitory Effect ◽

Control Group ◽

Ht29 Cells ◽

Guluronic Acid ◽

Tlr4 Mrna

Background: The non-steroidal anti-inflammatory drugs (NSAIDs) play crucial role in the controlling of inflammatory diseases. Due to the vast side effects of NSAIDs, its use is limited. G2013 or &#945;-L-Guluronic Acid is a new NSAID with immunomodulatory features. Objectives: Considering the leading role of TLRs in inflammatory responses, in this study, we aimed to evaluate G2013 cytotoxicity and its effect on the expression of TLR2 and TLR4 molecules. Methods: HEK293-TLR2 and HEK293-TLR4 cells were cultured and seeded on 96-well cell plate, and MTT assay was performed for detecting the viability of the cells after treatment with different concentrations of G2013. HT29 cells were grown and treated with low and high doses of G2013. After total RNA extraction and cDNA synthesis, quantitative real-time PCR were performed to assess the TLR2 and TLR4 mRNA synthesis. Results: We found that concentrations of ≤125 &#181;g/ml of G2013 had no apparent cytotoxicity effect on the HEK293-TLR2 and -TLR4 cells. Our results indicated that after G2013 treatment (5 &#181;g/ml) in HT29 cells, TLR2 and TLR4 mRNA expression decreased significantly compared with the untreated control group (p=0.02 and p=0.001 respectively). Conclusion: The results of this study revealed that G2013 can down regulate the TLR2 and TLR4 gene expression and exerts its inhibitory effect. Our findings are parallel to our previous finding which showed G2013 ability to down regulate the signaling pathway of TLRs. However, further studies are needed to identify the molecular mechanism of G2013.<p>

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BAFF Blockade Attenuates Inflammatory Responses and Intestinal Barrier Dysfunction in a Murine Endotoxemia Model

Frontiers in Immunology ◽

10.3389/fimmu.2020.570920 ◽

2020 ◽

Vol 11 ◽

Author(s):

Runze Quan ◽

Chaoyue Chen ◽

Wei Yan ◽

Ying Zhang ◽

Xi Zhao ◽

...

Keyword(s):

Barrier Function ◽

Intestinal Inflammation ◽

Inflammatory Responses ◽

Survival Rates ◽

Intestinal Barrier ◽

Intestinal Barrier Function ◽

Barrier Dysfunction ◽

Protein Levels ◽

Lps Challenge ◽

Endotoxemia Model

B cell-activating factor (BAFF) production is increased in septic patients. However, the specific role of BAFF in sepsis remains unknown. This study was designed to investigate the expression and function of BAFF in an experimental endotoxemia model and to identify the potential mechanisms. We established an endotoxemia mouse (6–8 weeks, 20–22 g) model by administering 30 mg/kg lipopolysaccharide (LPS). BAFF levels in the circulating system and organ tissues were measured 4 and 8 h after LPS injection. Survival rates in the endotoxemia mice were monitored for 72 h after BAFF blockade. The effects of BAFF blockade on systemic and local inflammation, organ injuries, and intestinal barrier function were also evaluated 4 h after LPS treatment. BAFF production was systemically and locally elevated after LPS challenge. BAFF blockade improved the survival rate, systemic inflammation, and multi-organ injuries. Moreover, BAFF blockade attenuated both intestinal inflammation and impaired intestinal permeability. BAFF blockade upregulated ZO-1 and occludin protein levels via the NF-κB/MLCK/MLC signaling pathway. These results suggested that BAFF blockade protects against lethal endotoxemia at least partially by alleviating inflammation, multi-organ injuries, and improving intestinal barrier function and provides a novel focus for further research on sepsis and experimental evidence for clinical therapy.

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Gut Microbiota-Derived Propionate Regulates the Expression of Reg3 Mucosal Lectins and Ameliorates Experimental Colitis in Mice

Journal of Crohn s and Colitis ◽

10.1093/ecco-jcc/jjaa065 ◽

2020 ◽

Vol 14 (10) ◽

pp. 1462-1472 ◽

Cited By ~ 2

Author(s):

Danica Bajic ◽

Adrian Niemann ◽

Anna-Katharina Hillmer ◽

Raquel Mejias-Luque ◽

Sena Bluemel ◽

...

Keyword(s):

Protective Factor ◽

Experimental Colitis ◽

Short Chain Fatty Acids ◽

Stem Cell Marker ◽

Knock Out ◽

Interleukin 22 ◽

Epithelial Regeneration ◽

Dss Colitis ◽

Colitis Model

Abstract Background and Aims Regenerating islet-derived protein type 3 [Reg3] lectins are antimicrobial peptides at mucosal surfaces of the gut, whose expression is regulated by pathogenic gut microbes via interleukin-22- or Toll-like receptor signalling. In addition to antimicrobial effects, tissue protection is hypothesized, but has been poorly investigated in the gut. Methods We applied antibiotic-induced microbiota perturbations, gnotobiotic approaches and a dextran-sodium sulfate [DSS] colitis model to assess microbial Reg3 regulation in the intestines and its role in colitis. We also used an intestinal organoid model to investigate this axis in vitro. Results First, we studied whether gut commensals are involved in Reg3 expression in mice, and found that antibiotic-mediated reduction of Clostridia downregulated intestinal Reg3B. A loss in Clostridia was accompanied by a significant reduction of short-chain fatty acids [SCFAs], and knock-out [KO] mice for SCFA receptors GPR43 and GPR109 expressed less intestinal Reg3B/-G. Propionate was found to induce Reg3 in intestinal organoids and in gnotobiotic mice colonized with a defined, SCFA-producing microbiota. Investigating the role of Reg3B as a protective factor in colitis, we found that Reg3B-KO mice display increased inflammation and less crypt proliferation in the DSS colitis model. Propionate decreased colitis and increased proliferation. Treatment of organoids exposed to DSS with Reg3B or propionate reversed the chemical injury with a loss of expression of the stem-cell marker Lgr5 and Olfm4. Conclusions Our results suggest that Clostridia can regulate Reg3-associated epithelial homeostasis through propionate signalling. We also provide evidence that the Reg3–propionate axis may be an important mediator of gut epithelial regeneration in colitis.

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A Salmonella Virulence Factor Activates the NOD1/NOD2 Signaling Pathway

mBio ◽

10.1128/mbio.00266-11 ◽

2011 ◽

Vol 2 (6) ◽

Cited By ~ 18

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.

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Dehydroepiandrosterone (DHEA) restrains intestinal inflammation by rendering leukocytes hyporesponsive and balancing colitogenic inflammatory responses

Immunobiology ◽

10.1016/j.imbio.2016.05.013 ◽

2016 ◽

Vol 221 (9) ◽

pp. 934-943 ◽

Cited By ~ 9

Author(s):

Vanessa Beatriz Freitas Alves ◽

Paulo José Basso ◽

Viviani Nardini ◽

Angélica Silva ◽

Javier Emílio Lazo Chica ◽

...

Keyword(s):

Intestinal Inflammation ◽

Inflammatory Responses

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Gluten-induced RNA methylation changes regulate intestinal inflammation via allele-specific XPO1 translation in epithelial cells

Gut ◽

10.1136/gutjnl-2020-322566 ◽

2021 ◽

pp. gutjnl-2020-322566

Author(s):

Ane Olazagoitia-Garmendia ◽

Linda Zhang ◽

Paula Mera ◽

Julie K Godbout ◽

Maialen Sebastian-DelaCruz ◽

...

Keyword(s):

Intestinal Inflammation ◽

Autoimmune Disorder ◽

Intestinal Cell ◽

In Vivo Models ◽

Knock Out ◽

New Therapeutic Approaches ◽

Intestinal Cell Line ◽

Environment Characteristic

ObjectivesCoeliac disease (CD) is a complex autoimmune disorder that develops in genetically susceptible individuals. Dietary gluten triggers an immune response for which the only available treatment so far is a strict, lifelong gluten free diet. Human leucocyte antigen (HLA) genes and several non-HLA regions have been associated with the genetic susceptibility to CD, but their role in the pathogenesis of the disease is still essentially unknown, making it complicated to develop much needed non-dietary treatments. Here, we describe the functional involvement of a CD-associated single-nucleotide polymorphism (SNP) located in the 5’UTR of XPO1 in the inflammatory environment characteristic of the coeliac intestinal epithelium.DesignThe function of the CD-associated SNP was investigated using an intestinal cell line heterozygous for the SNP, N6-methyladenosine (m6A)-related knock-out and HLA-DQ2 mice, and human samples from patients with CD.ResultsIndividuals harbouring the risk allele had higher m6A methylation in the 5’UTR of XPO1 RNA, rendering greater XPO1 protein amounts that led to downstream nuclear factor kappa B (NFkB) activity and subsequent inflammation. Furthermore, gluten exposure increased overall m6A methylation in humans as well as in in vitro and in vivo models.ConclusionWe identify a novel m6A-XPO1-NFkB pathway that is activated in CD patients. The findings will prompt the development of new therapeutic approaches directed at m6A proteins and XPO1, a target under evaluation for the treatment of intestinal disorders.

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