IL-22-STAT3 Pathway Plays a Key Role in the Maintenance of Ileal Homeostasis in Mice Lacking Secreted Mucus Barrier
Sovran, B. ; Loonen, L.M.P. ; Hugenholtz, F. ; Belzer, C. ; Kranenbarg-Stolte, H.H. ; Boekschoten, M.V. ; Baarlen, P. van; Kleerebezem, M. ; Vos, P. de; Dekker, J. ; Renes, I.B. ; Wells, J.M. - \ 2015
Inflammatory Bowel Diseases 21 (2015)3. - ISSN 1078-0998 - p. 531 - 542.
inflammatory-bowel-disease - pancreatitis-associated protein - intestinal epithelial-cells - colonic gene-expression - experimental colitis - muc2-deficient mice - mucin muc2 - microbiota - bacteria - stat3
Background: Muc2-deficient mice show no signs of ileal pathology but the mechanisms remained unknown. Methods: Wild-type (WT), Muc2+/-, and Muc2-/- mice were killed at 2, 4, and 8 weeks of age. Total RNA from ileum was used for full genome transcriptome analysis and qPCR. Microbiota composition was determined using a mouse intestinal chip (MITChip). Morphological and immunohistological studies were performed on segments of ileum. Results: The ileum was colonized by more diverse microbiota in young (week 4) WT than in Muc2-/- mice, and composition was influenced by genotype. Weaning was associated with major changes in the transcriptome of all mice, and the highest number of differentially expressed genes compared with adults, reflecting temporal changes in microbiota. Although the spatial compartmentalization of bacteria was compromised in Muc2-/- mice, gene set enrichment analysis revealed a downregulation of Toll-like receptor, immune, and chemokine signaling pathways compared to WT mice. The predicted effects of enhanced IL-22 signaling were identified in the Muc2-/- transcriptome as the upregulation of epithelial cell proliferation altered expression of mitosis and cell-cycle control pathways. This is consistent with increased villus length and number of Ki67+ epithelial cells in Muc2-/- mice. Additionally, expression of the network of IL-22 regulated defense genes, including Fut2, Reg3[beta], Reg3[gamma], Relmb, and the Defensin Defb46 were increased in Muc2-/- mice. Conclusions: These findings highlight a role for the IL-22-STAT3 pathway in maintaining ileal homeostasis when the mucus barrier is compromised and its potential as a target for novel therapeutic strategies in inflammatory bowel disease
Cytotoxicity and metabolic stress induced by acetaldehyde in human intestinal LS174T goblet-like cells
Elamin, E. ; Masclee, A. ; Troost, F. ; Dekker, J. ; Jonkers, D. - \ 2014
American Journal of Physiology. Gastrointestinal and Liver Physiology 307 (2014)3. - ISSN 0193-1857 - p. G286 - G294.
mediated endothelial permeability - inflammatory-bowel-disease - in-vitro - epithelial barrier - liver-disease - oral-mucosa - aldehyde dehydrogenases - plasma endotoxin - tight junctions - ethanol
There is compelling evidence indicating that ethanol and its oxidative metabolite acetaldehyde can disrupt intestinal barrier function. Apart from the tight junctions, mucins secreted by goblet cells provide an effective barrier. Ethanol has been shown to induce goblet cell injury associated with alterations in mucin glycosylation. However, effects of its most injurious metabolite acetaldehyde remain largely unknown. This study aimed to assess short-term effects of acetaldehyde (0, 25, 50, 75, 100 mu M) on functional characteristics of intestinal goblet-like cells (LS174T). Oxidative stress, mitochondrial function, ATP, and intramitochondrial calcium (Ca2+) were assessed by dichlorofluorescein, methyltetrazolium, and bioluminescence, MitoTracker green and rhod-2 double-labeling. Membrane integrity and apoptosis were evaluated by measuring lactate dehydrogenase (LDH), caspase 3/7, and cleavage of cytokeratin 18 (CK18). Expression of mucin 2 (MUC2) was determined by cell-based ELISA. Acetaldehyde significantly increased reactive oxygen species generation and decreased mitochondrial function compared with negative controls (P <0.05). In addition, acetaldehyde dose-dependently decreased ATP levels and induced intramitochondrial Ca2+ accumulation compared with negative controls (P <0.05). Furthermore, acetaldehyde induced LDH release and increased caspase3/7 activity and percentage of cells expressing cleaved CK18 and increased MUC2 protein expression compared with negative controls (P <0.0001). ATP depletion and LDH release could be largely prevented by the antioxidant N-acetylcysteine, suggesting a pivotal role for oxidative stress. Our data demonstrate that acetaldehyde has distinct oxidant-dependent metabolic and cytotoxic effects on LS174T cells that can lead to induction of cellular apoptosis. These effects may contribute to acetaldehyde-induced intestinal barrier dysfunction and subsequently to liver injury.
Comparative studies of Toll-like receptor signalling using zebrafish
Kanwal, Z. ; Wiegertjes, G. ; Veneman, W.J. ; Meijer, A.H. ; Spaink, H.P. - \ 2014
Developmental and Comparative Immunology 46 (2014)1. - ISSN 0145-305X - p. 35 - 52.
nf-kappa-b - protein-tyrosine-phosphatase - pattern-recognition receptors - innate immune-response - leucine-rich repeats - activating transcription factor-3 - hematopoietic-cell phosphatase - inflammatory-bowel-disease - antigen-presenting cells - carp cyprinus-c
Zebrafish model systems for infectious disease are increasingly used for the functional analysis of molecular pattern recognition processes. These studies benefit from the high conservation level of all innate immune factors in vertebrates. Zebrafish studies are strategically well positioned for this because of the ease of comparisons with studies in other fish species of which the immune system also has been intensively studied, but that are currently still less amendable to detailed genetic or microscopic studies. In this paper we focus on Toll-like receptor (TLR) signalling factors, which currently are the best characterized in mammalian systems. We review the knowledge on TLR signalling in the context of recent advances in zebrafish studies and discuss possibilities for future approaches that can complement studies in cell cultures and rodent models. A focus in these comparisons is the role of negative control mechanisms in immune responses that appear very important in a whole organism to keep adverse systemic responses in check. We also pay much attention to comparisons with studies in common carp that is highly related to zebrafish and that because of its large body mass can complement immune studies in zebrafish.
Sexually dimorphic characteristics of the small intestine and colon of prepubescent C57BL/6 mice
Steegenga, W.T. ; Mischke, M. ; Lute, C. ; Boekschoten, M.V. ; Pruis, M.G.M. ; Lendvai, A. ; Verkade, H.J. ; Boekhorst, J. ; Timmerman, H.M. ; Plösch, T. ; Müller, M.R. - \ 2014
Biology of Sex Differences 5 (2014). - ISSN 2042-6410 - 17 p.
liver gene-expression - inflammatory-bowel-disease - inactive x-chromosome - genome-wide analysis - sex-differences - mouse-liver - gut microbiota - pancreatic-secretion - microarray analysis - epithelial-cells
Background There is increasing appreciation for sexually dimorphic effects, but the molecular mechanisms underlying these effects are only partially understood. In the present study, we explored transcriptomics and epigenetic differences in the small intestine and colon of prepubescent male and female mice. In addition, the microbiota composition of the colonic luminal content has been examined. Methods At postnatal day 14, male and female C57BL/6 mice were sacrificed and the small intestine, colon and content of luminal colon were isolated. Gene expression of both segments of the intestine was analysed by microarray analysis. DNA methylation of the promoter regions of selected sexually dimorphic genes was examined by pyrosequencing. Composition of the microbiota was explored by deep sequencing. Results Sexually dimorphic genes were observed in both segments of the intestine of 2-week-old mouse pups, with a stronger effect in the small intestine. Amongst the total of 349 genes displaying a sexually dimorphic effect in the small intestine and/or colon, several candidates exhibited a previously established function in the intestine (i.e. Nts, Nucb2, Alox5ap and Retnl¿). In addition, differential expression of genes linked to intestinal bowel disease (i.e. Ccr3, Ccl11 and Tnfr) and colorectal cancer development (i.e. Wt1 and Mmp25) was observed between males and females. Amongst the genes displaying significant sexually dimorphic expression, nine genes were histone-modifying enzymes, suggesting that epigenetic mechanisms might be a potential underlying regulatory mechanism. However, our results reveal no significant changes in DNA methylation of analysed CpGs within the selected differentially expressed genes. With respect to the bacterial community composition in the colon, a dominant effect of litter origin was found but no significant sex effect was detected. However, a sex effect on the dominance of specific taxa was observed. Conclusions This study reveals molecular dissimilarities between males and females in the small intestine and colon of prepubescent mice, which might underlie differences in physiological functioning and in disease predisposition in the two sexes.
Faecal Microbiota Composition in Adults Is Associated with the FUT2 Gene Determining the Secretor Status
Wacklin, P. ; Tuimala, J. ; Nikkilä, J. ; Tims, S. ; Mäkivuokko, H. ; Alakulppi, N. ; Laine, P. ; Rajilic-Stojanovic, M. ; Paulin, L. ; Vos, W.M. de; Mättö, J. - \ 2014
PLoS ONE 9 (2014)4. - ISSN 1932-6203
inflammatory-bowel-disease - human gut microbiome - blood-group antigens - intestinal microbiota - crohns-disease - celiac-disease - mucosa - twins - galactosidase - enterotypes
The human intestine is colonised with highly diverse and individually defined microbiota, which likely has an impact on the host well-being. Drivers of the individual variation in the microbiota compositions are multifactorial and include environmental, host and dietary factors. We studied the impact of the host secretor status, encoded by fucosyltransferase 2 (FUT2) -gene, on the intestinal microbiota composition. Secretor status determines the expression of the ABH and Lewis histo-blood group antigens in the intestinal mucosa. The study population was comprised of 14 non-secretor (FUT2 rs601338 genotype AA) and 57 secretor (genotypes GG and AG) adult individuals of western European descent. Intestinal microbiota was analyzed by PCR-DGGE and for a subset of 12 non-secretor subjects and 12 secretor subjects additionally by the 16S rRNA gene pyrosequencing and the HITChip phylogenetic microarray analysis. All three methods showed distinct clustering of the intestinal microbiota and significant differences in abundances of several taxa representing dominant microbiota between the non-secretors and the secretors as well as between the FUT2 genotypes. In addition, the non-secretors had lower species richness than the secretors. The soft clustering of microbiota into enterotypes (ET) 1 and 3 showed that the non-secretors had a higher probability of belonging to ET1 and the secretors to ET3. Our study shows that secretor status and FUT2 polymorphism are associated with the composition of human intestinal microbiota, and appears thus to be one of the key drivers affecting the individual variation of human intestinal microbiota.
Eicosapentaenoic acid free fatty acid prevents and suppresses colonic neoplasia in colitis-associated colorectal cancer acting on Notch signaling and gut microbiota
Piazzi, G. ; Argenio, G. D'; Prossomariti, A. ; Lembo, V. ; Mazzone, G. ; Candela, M. ; Biagi, E. ; Brigidi, P. ; Vitaglione, P. ; Fogliano, V. ; Angelo and others, L. D' - \ 2014
International Journal of Cancer 135 (2014)9. - ISSN 0020-7136 - p. 2004 - 2013.
inflammatory-bowel-disease - dietary fish-oil - intestinal microbiota - mouse model - docosahexaenoic acid - mice - sodium - cells - differentiation - chemoprevention
Inflammatory bowel diseases are associated with increased risk of developing colitis-associated colorectal cancer (CAC). Epidemiological data show that the consumption of ¿-3 polyunsaturated fatty acids (¿-3 PUFAs) decreases the risk of sporadic colorectal cancer (CRC). Importantly, recent data have shown that eicosapentaenoic acid-free fatty acid (EPA-FFA) reduces polyp formation and growth in models of familial adenomatous polyposis. However, the effects of dietary EPA-FFA are unknown in CAC. We tested the effectiveness of substituting EPA-FFA, for other dietary fats, in preventing inflammation and cancer in the AOM-DSS model of CAC. The AOM-DSS protocols were designed to evaluate the effect of EPA-FFA on both initiation and promotion of carcinogenesis. We found that EPA-FFA diet strongly decreased tumor multiplicity, incidence and maximum tumor size in the promotion and initiation arms. Moreover EPA–FFA, in particular in the initiation arm, led to reduced cell proliferation and nuclear ß-catenin expression, whilst it increased apoptosis. In both arms, EPA-FFA treatment led to increased membrane switch from ¿-6 to ¿-3 PUFAs and a concomitant reduction in PGE2 production. We observed no significant changes in intestinal inflammation between EPA-FFA treated arms and AOM-DSS controls. Importantly, we found that EPA-FFA treatment restored the loss of Notch signaling found in the AOM-DSS control and resulted in the enrichment of Lactobacillus species in the gut microbiota. Taken together, our data suggest that EPA-FFA is an excellent candidate for CRC chemoprevention in CAC.
Ethanol metabolism and its effects on the intestinal epithelial barrier
Elamin, E.E. ; Masclee, A.A. ; Dekker, J. ; Jonkers, D.M. - \ 2013
Nutrition Reviews 71 (2013)7. - ISSN 0029-6643 - p. 483 - 499.
acid ethyl-esters - caco-2 cell monolayer - alcoholic liver-disease - tight-junction barrier - induced gut leakiness - mediated acetaldehyde production - human gastrointestinal-tract - inflammatory-bowel-disease - pancreatic acinar-cells - chain kinase expression
Ethanol is widely consumed and is associated with an increasing global health burden. Several reviews have addressed the effects of ethanol and its oxidative metabolite, acetaldehyde, on the gastrointestinal (GI) tract, focusing on carcinogenic effects or alcoholic liver disease. However, both the oxidative and the nonoxidative metabolites of ethanol can affect the epithelial barrier of the small and large intestines, thereby contributing to GI and liver diseases. This review outlines the possible mechanisms of ethanol metabolism as well as the effects of ethanol and its metabolites on the intestinal barrier. Limited studies in humans and supporting in vitro data have indicated that ethanol as well as mainly acetaldehyde can increase small intestinal permeability. Limited evidence also points to increased colon permeability following exposure to ethanol or acetaldehyde. In vitro studies have provided several mechanisms for disruption of the epithelial barrier, including activation of different cell-signaling pathways, oxidative stress, and remodeling of the cytoskeleton. Modulation via intestinal microbiota, however, should also be considered. In conclusion, ethanol and its metabolites may act additively or even synergistically in vivo. Therefore, in vivo studies investigating the effects of ethanol and its byproducts on permeability of the small and large intestines are warranted.
Therapeutic potential of fecal microbiota transplantation
Smits, L.P. ; Bouter, K.E.C. ; Vos, W.M. de; Borody, T.J. ; Nieuwdorp, M. - \ 2013
Gastroenterology 145 (2013)5. - ISSN 0016-5085 - p. 946 - 953.
clostridium-difficile-infection - inflammatory-bowel-disease - fatty liver-disease - increased intestinal permeability - chronic-fatigue-syndrome - term-follow-up - cardiovascular-disease - chronic constipation - colonic microbiota - gut microbiota
There has been growing interest in the use of fecal microbiota for the treatment of patients with chronic gastrointestinal infections and inflammatory bowel diseases. Lately, there has also been interest in its therapeutic potential for cardiometabolic, autoimmune, and other extraintestinal conditions that were not previously considered to be associated with the intestinal microbiota. Although it is not clear if changes in the microbiota cause these conditions, we review the most current and best methods for performing fecal microbiota transplantation and summarize clinical observations that have implicated the intestinal microbiota in various diseases. We also discuss case reports of fecal microbiota transplantations for different disorders, including Clostridium difficile infection, irritable bowel syndrome, inflammatory bowel diseases, insulin resistance, multiple sclerosis, and idiopathic thrombocytopenic purpura. There has been increasing focus on the interaction between the intestinal microbiome, obesity, and cardiometabolic diseases, and we explore these relationships and the potential roles of different microbial strains. We might someday be able to mine for intestinal bacterial strains that can be used in the diagnosis or treatment of these diseases
Monitoring immune modulation by nutrition in the general population: identifying and substantiating effects on human health.
Albers, R. ; Bourdet-Sicard, R. ; Braun, D. ; Calder, P.C. ; Herz, U. ; Lambert, C. ; Lenoir-Wijnkoop, I. ; Meheust, A. ; Ouwehand, A. ; Phothirath, P. ; Sako, T. ; Salminen, S. ; Siemensma, A. ; Loveren, H. van; Sack, U. - \ 2013
The British journal of nutrition 110 (2013)S2. - ISSN 0007-1145 - p. S1 - S30.
c-reactive protein - regulatory t-cells - coronary-heart-disease - atopy patch test - randomized controlled-trial - inflammatory-bowel-disease - respiratory symptom survey - hymenoptera venom allergy - basophil activation test - hepatitis-b vaccination
Optimal functioning of the immune system is crucial to human health, and nutrition is one of the major exogenous factors modulating different aspects of immune function. Currently, no single marker is available to predict the effect of a dietary intervention on different aspects of immune function. To provide further guidance on the assessment and interpretation of the modulation of immune functions due to nutrition in the general population, International Life Sciences Institute Europe commissioned a group of experts from academia, government and the food industry to prepare a guidance document. A draft of this paper was refined at a workshop involving additional experts. First, the expert group defined criteria to evaluate the usefulness of immune function markers. Over seventy-five markers were scored within the context of three distinct immune system functions: defence against pathogens; avoidance or mitigation of allergy; control of low-grade (metabolic) inflammation. The most useful markers were subsequently classified depending on whether they by themselves signify clinical relevance and/or involvement of immune function. Next, five theoretical scenarios were drafted describing potential changes in the values of markers compared with a relevant reference range. Finally, all elements were combined, providing a framework to aid the design and interpretation of studies assessing the effects of nutrition on immune function. This stepwise approach offers a clear rationale for selecting markers for future trials and provides a framework for the interpretation of outcomes. A similar stepwise approach may also be useful to rationalise the selection and interpretation of markers for other physiological processes critical to the maintenance of health and well-being.
Probiotics can generate FoxP3 T-cell responses in the small intestine and simultaneously inducing CD4 and CD8 T cell activation in the large intestine.
Smelt, M.J. ; Haan, B.J. de; Bron, P.A. ; Swam, I. van; Meijerink, M. ; Wells, J. ; Faas, M.M. ; Vos, P. de - \ 2013
PLoS ONE 8 (2013)7. - ISSN 1932-6203
inflammatory-bowel-disease - influenza-virus infection - cd103(+) dendritic cells - complete genome sequence - lactic-acid bacteria - lactobacillus-plantarum - double-blind - in-vitro - maintaining remission - ulcerative-colitis
Most studies on probiotics aim to restore intestinal homeostasis to reduce immune-pathology in disease. Of equal importance are studies on how probiotics might prevent or delay disease in healthy individuals. However, knowledge on mechanisms of probiotic actions in healthy individuals is scarce. To gain more insight in how different bacterial strains may modulate the healthy intestinal immune system, we investigated the effect of the food derived bacterial strains L. plantarum WCFS1, L. salivarius UCC118, and L. lactis MG1363, on the intestinal regulatory immune phenotype in healthy mice. All three bacterial strains induced an upregulation of activity and numbers of CD11c(+) MHCII(+) DCs in the immune-sampling Peyer's Patches. Only L. salivarius UCC118 skewed towards an immune regulatory phenotype in the small intestinal lamina propria (SILP). The effects were different in the large intestine lamina propria. L. salivarius UCC118 induced activation in both CD4 and CD8 positive T-cells while L. plantarum WCFS1 induced a more regulatory phenotype. Moreover, L. plantarum WCFS1 decreased the Th1/Th2 ratio in the SILP. Also L. lactis MG1363 had immunomodulatory effects. L. lactis MG1363 decreased the expression of the GATA-3 and T-bet in the SILP. As our data show that contradictory effects may occur in different parts of the gut, it is recommended to study effects of probiotic in different sites in the intestine. Our strain-specific results suggest that unspecified application of probiotics may not be very effective. Our data also indicate that selection of specific probiotic strain activities on the basis of responses in healthy mice may be a promising strategy to specifically stimulate or suppress immunity in specific parts of the intestine
Resistant Starch Induces Catabolic but Suppresses Immune and Cell Division Pathways and Changes the Microbiome in Proximal Colon of Male Pigs
Haenen, D. ; Souza Da Silva, C. ; Zhang, J. ; Koopmans, S.J. ; Bosch, G. ; Vervoort, J.J.M. ; Gerrits, W.J.J. ; Kemp, B. ; Smidt, H. ; Müller, M.R. ; Hooiveld, G.J.E.J. - \ 2013
The Journal of Nutrition 143 (2013)12. - ISSN 0022-3166 - p. 1889 - 1898.
chain fatty-acids - inflammatory-bowel-disease - endoplasmic-reticulum stress - butyrate-producing bacteria - activated receptor-gamma - human large-intestine - gene-expression - gastrointestinal-tract - transcription factors - gut microbiota
Consumption of resistant starch (RS) has been associated with various intestinal health benefits, but knowledge on its effects on global gene expression in the colon is limited. The main objective of the current study was to identify genes affected by RS in the proximal colon to infer which biologic pathways were modulated. Ten 17-wk-old male pigs, fitted with a cannula in the proximal colon for repeated collection of tissue biopsy samples and luminal content, were fed a digestible starch (DS) diet or a diet high in RS (34%) for 2 consecutive periods of 14 d in a crossover design. Analysis of the colonic transcriptome profiles revealed that, upon RS feeding, oxidative metabolic pathways, such as the tricarboxylic acid cycle and ß-oxidation, were induced, whereas many immune response pathways, including adaptive and innate immune system, as well as cell division were suppressed. The nuclear receptor peroxisome proliferator-activated receptor ¿ (PPARG) was identified as a potential key upstream regulator. RS significantly (P <0.05) increased the relative abundance of several butyrate-producing microbial groups, including the butyrate producers Faecalibacterium prausnitzii and Megasphaera elsdenii, and reduced the abundance of potentially pathogenic members of the genus Leptospira and the phylum Proteobacteria. Concentrations in carotid plasma of the 3 main short-chain fatty acids acetate, propionate, and butyrate were significantly higher with RS consumption compared with DS consumption. Overall, this study provides novel insights on effects of RS in proximal colon and contributes to our understanding of a healthy diet.
Molecular signatures for the dynamic process of establishing intestinal host-microbial homeostasis: potential for disease diagnostics?
Aidy, S.F. El; Kleerebezem, M. - \ 2013
Current Opinion in Gastroenterology 29 (2013)6. - ISSN 0267-1379 - p. 621 - 627.
inflammatory-bowel-disease - gut microbiota - gene-expression - immune-system - health - diet - mucosa - twins - mice - conventionalisation
Purpose of review: The dynamic interplay of the intestinal microbiota and host has been the focus of many studies because of its impact on the health status in human life. Recent reports on the time-resolved immune and metabolic interactions between the host and microbiota, as well as the molecular signatures that mark this communication during the process of establishing a host–microbial relationship, are addressed here. Recent findings: During microbial colonization, the progressive impact of de-novo introduction of the gut microbiota on the host's physiology is tightly controlled by highly intertwined regulatory networks and achieves an efficient and balanced interplay between the host and its developing microbial community. Recent findings from germ-free mouse models have unravelled core transcriptional, metabolic and microbial signatures, which are proposed to orchestrate the molecular responses during the establishment of the multifaceted state of intestinal host–microbe homeostasis. Summary: Exploring the time-resolved dynamics of the host responses to the newly colonizing gut microbiota provides mechanistically critical understanding of the sequential host–microbe response cascades that lead to a homeostatic relationship. Thereby, these approaches can provide novel diagnostic tools and therapeutic targets, or either of the two, in humans for specific disorders associated with intestinal dysbiosis and loss of homeostasis
The Impact of Lactobacillus plantarum WCFS1 Teichoic Acid D-Alanylation on the Generation of Effector and Regulatory T-cells in Healthy Mice
Smelt, M.J. ; Haan, B.J. de; Bron, P.A. ; Swam, I. van; Meijerink, M. ; Wells, J. ; Kleerebezem, M. ; Faas, M.M. ; Vos, P. de - \ 2013
PLoS ONE 8 (2013)4. - ISSN 1932-6203 - 14 p.
placebo-controlled trial - inflammatory-bowel-disease - blood mononuclear-cells - tlr signaling pathways - lipoteichoic acid - double-blind - dendritic cells - ulcerative-colitis - maintaining remission - acidophilus deficient
To date it remains unclear how probiotics affect the immune system. Bacterial envelope components may play an essential role, as these are the first to establish bacterial-host cell interactions. Teichoic acids (TAs), and especially lipoteichoic acids, are the most pro-inflammatory components of the gram-positive bacterial envelope. This effect is dependent on D-alanyl substitution of the TA backbone and interactions with TLR2 on host cells. Although the pro-inflammatory properties of TAs have been established in vitro, it remains unclear how TAs affect immunomodulation in vivo. In this study, we investigated the role of TA D-alanylation on L. plantarum–induced intestinal and systemic immunomodulation in vivo. For this, we compared the effect of L. plantarum WCFS1 and its TA D-Alanylation negative derivative (dltX-D) on the distribution of dendritic cell and T cell populations and responses in healthy mice. We demonstrated that the majority of the L. plantaruminduced in vivo immunomodulatory effects were dependent on D-alanylation (D-Ala), as some L. plantarum WCFS1-induced immune changes were not observed in the dltX-D-treated group and some were only observed after treatment with dltX-D. Strikingly, not only pro-inflammatory immune responses were abolished in the absence of D-Ala substitution, but also antiinflammatory responses, such as the L. plantarum-induced generation of regulatory T cells in the spleen. With this study we provide insight in host-microbe interactions, by demonstrating the involvement of D-alanylation of TAs on the bacterial membrane in intestinal and systemic immunomodulation in healthy mice.
Glycobiome: Bacteria and mucus at the epithelial interface
Ouwerkerk, J.P. ; Vos, W.M. de; Belzer, C. - \ 2013
Best Practice & Research: Clinical Gastroenterology 27 (2013)1. - ISSN 1521-6918 - p. 25 - 38.
inflammatory-bowel-disease - mucosa-associated microbiota - human gut microbiota - abo blood-group - intestinal microbiota - human colon - in-vivo - akkermansia-muciniphila - spatial-organization - bacteroides-thetaiotaomicron
The human gastrointestinal tract is colonised with a dense and diverse microbial community, that is an important player in human health and physiology. Close to the epithelial cells the mucosal microbiota is separated from the host with a thin lining of host derived glycans, including the cell surface glycocalyx and the extracellular secreted mucus. The mucosa-associated microbial composition differs from the luminal content and could be particularly important for nutrient exchange, communication with the host, development of the immune system, and resistance against invading pathogens. The mucosa-associated microbiota has adapted to the glycan rich environment by the production of mucus-degrading enzymes and mucus-binding extracellular proteins, and include mucus-degrading specialists such as Akkermansia muciniphila and Bacteroides thetaiotaomicron. This review is focussed on the host-microbe interactions within the glycan landscape at the epithelial interface and considers the spatial organisation and composition of the mucosa-associated microbiota in health and disease
Short chain fatty acids stimulate Angiopoietin-like 4 synthesis in human colon adenocarcinoma cells by activating PPARy
Alex, S. ; Lange, K. ; Amolo, T. ; Grinstead, J.S. ; Haakonsson, A.K. ; Szalowska, E. ; Koppen, A. ; Mudde, C.M. ; Haenen, D. ; Al-Lahham, S. ; Roelofsen, H. ; Houtman, R. ; Burg, B. van der; Mandrup, S. ; Bonvin, A.M.J.J. ; Kalkhoven, E. ; Muller, M.R. ; Hooiveld, G.J.E.J. ; Kersten, A.H. - \ 2013
Molecular and Cellular Biology 33 (2013)7. - ISSN 0270-7306 - p. 1303 - 1316.
inflammatory-bowel-disease - ppar-gamma - transcriptional activity - lipoprotein-lipase - skeletal-muscle - gut microbiota - target gene - expression - protein-4 - butyrate
Angiopoietin-like protein 4 (ANGPTL4/FIAF) has been proposed as a circulating mediator between the gut microbiota and fat storage. Here, we show that transcription and secretion of ANGPTL4 in human T84 and HT29 colon adenocarcinoma cells is highly induced by physiological concentrations of short-chain fatty acids (SCFA). SCFA induce ANGPTL4 by activating the nuclear receptor peroxisome proliferator activated receptor ¿ (PPAR¿), as demonstrated using PPAR¿ antagonist, PPAR¿ knockdown, and transactivation assays, which show activation of PPAR¿ but not PPARa and PPARd by SCFA. At concentrations required for PPAR¿ activation and ANGPTL4 induction in colon adenocarcinoma cells, SCFA do not stimulate PPAR¿ in mouse 3T3-L1 and human SGBS adipocytes, suggesting that SCFA act as selective PPAR¿ modulators (SPPARM), which is supported by coactivator peptide recruitment assay and structural modeling. Consistent with the notion that fermentation leads to PPAR activation in vivo, feeding mice a diet rich in inulin induced PPAR target genes and pathways in the colon. We conclude that (i) SCFA potently stimulate ANGPTL4 synthesis in human colon adenocarcinoma cells and (ii) SCFA transactivate and bind to PPAR¿. Our data point to activation of PPARs as a novel mechanism of gene regulation by SCFA in the colon, in addition to other mechanisms of action of SCFA.
Phylogenetic Analysis of Dysbiosis in Ulcerative Colitis During Remission
Rajilic-Stojanovic, M. ; Shanahan, F. ; Guarner, F. ; Vos, W.M. de - \ 2013
Inflammatory Bowel Diseases 19 (2013)3. - ISSN 1078-0998 - p. 481 - 488.
inflammatory-bowel-disease - gastrointestinal-tract microbiota - human intestinal-tract - clostridium-difficile - butyrate oxidation - colonic-mucosa - gut microbiota - diversity - bacteria - epidemiology
BACKGROUND:: Presence of intestinal microbes is a prerequisite for the development of ulcerative colitis (UC), although deviation of the normal intestinal microbiota composition, dysbiosis, is presumably implicated in the etiology of UC. METHODS:: The fecal microbiota of 30 UC samples obtained from 15 patients who were sampled twice and from 15 healthy control subjects originating from 2 geographic locations was analyzed using highly reproducible phylogenetic microarray that has the capacity for detection and quantification of more than 1000 intestinal bacteria in a wide dynamic range. RESULTS:: The fecal microbiota composition is not significantly influenced by geographic location, age, or gender, but it differs significantly between the patients with UC and the control subjects (P = 0.0004). UC-associated microbiota is stable during remission and similar among all patients with UC. Significant reduction of bacterial diversity of members of the Clostridium cluster IV and significant reduction in the abundance of bacteria involved in butyrate and propionate metabolism, including Ruminococcus bromii et rel. Eubacterium rectale et rel., Roseburia sp., and Akkermansia sp. are markers of dysbiosis in UC. Increased abundance of (opportunistic) pathogens including Fusobacterium sp., Peptostreptococcus sp., Helicobacter sp., and Campylobacter sp. as well as Clostridium difficile were found to be associated with UC. CONCLUSIONS:: Dysbiosis in UC is stable in time and shared between patients from different geographic locations. The microbial alterations offer a mechanistic insight into the pathogenesis of the disease
The gut microbiota elicits a profound metabolic reorientation in the mouse jejunal mucosa during conventionalisation
Aidy, S. El; Merrifield, C.A. ; Derrien, M. ; Baarlen, P. van; Hooiveld, G.J. ; Levenez, F. ; Dore, J. ; Dekker, J. ; Holmes, E. ; Claus, S.P. ; Reijngoud, D.J. ; Kleerebezem, M. - \ 2013
Gut 62 (2013). - ISSN 0017-5749 - p. 1306 - 1314.
inflammatory-bowel-disease - gastric bypass - amino-acid - glutamate - intestine - surgery - mice - biosynthesis - homeostasis - expression
OBJECTIVE: Proper interactions between the intestinal mucosa, gut microbiota and nutrient flow are required to establish homoeostasis of the host. Since the proximal part of the small intestine is the first region where these interactions occur, and since most of the nutrient absorption occurs in the jejunum, it is important to understand the dynamics of metabolic responses of the mucosa in this intestinal region. DESIGN: Germ-free mice aged 8-10 weeks were conventionalised with faecal microbiota, and responses of the jejunal mucosa to bacterial colonisation were followed over a 30-day time course. Combined transcriptome, histology, (1)H NMR metabonomics and microbiota phylogenetic profiling analyses were used. RESULTS: The jejunal mucosa showed a two-phase response to the colonising microbiota. The acute-phase response, which had already started 1 day after conventionalisation, involved repression of the cell cycle and parts of the basal metabolism. The secondary-phase response, which was consolidated during conventionalisation (days 4-30), was characterised by a metabolic shift from an oxidative energy supply to anabolic metabolism, as inferred from the tissue transcriptome and metabonome changes. Detailed transcriptome analysis identified tissue transcriptional signatures for the dynamic control of the metabolic reorientation in the jejunum. The molecular components identified in the response signatures have known roles in human metabolic disorders, including insulin sensitivity and type 2 diabetes mellitus. CONCLUSION: This study elucidates the dynamic jejunal response to the microbiota and supports a prominent role for the jejunum in metabolic control, including glucose and energy homoeostasis. The molecular signatures of this process may help to find risk markers in the declining insulin sensitivity seen in human type 2 diabetes mellitus, for instance.
Long-term monitoring of the human intestinal microbiota composition
Rajilic-Stojanovic, M. ; Heilig, G.H.J. ; Tims, S. ; Zoetendal, E.G. ; Vos, W.M. de - \ 2013
Environmental Microbiology 15 (2013)4. - ISSN 1462-2912 - p. 1146 - 1159.
16s ribosomal-rna - inflammatory-bowel-disease - gut microbiota - temporal stability - fecal microbiota - human feces - bacterial - microflora - commensal - flora
The microbiota that colonizes the human intestinal tract is complex and its structure is specific for each of us. In this study we expand the knowledge about the stability of the subject-specific microbiota and show that this ecosystem is stable in short-term intervals (¿10 years). The faecal microbiota composition of five unrelated and healthy subjects was analysed using a comprehensive and highly reproducible phylogenetic microarray, the HITChip. The results show that the use of antibiotics, application of specific dietary regimes and distant travelling have limited impact on the microbiota composition. Several anaerobic genera, including Bifidobacterium and a number of genera within the Bacteroidetes and the Firmicutes phylum, exhibit significantly higher similarity than the total microbiota. Although the gut microbiota contains subject-specific species, the presence of which is preserved throughout the years, their relative abundance changes considerably. Consequently, the recently proposed enterotype status appears to be a varying characteristic of the microbiota. Our data show that the intestinal microbiota contains a core community of permanent colonizers, and that environmentally introduced changes of the microbiota throughout adulthood are primarily affecting the abundance but not the presence of specific microbial species
Butyrate-producing Clostridium cluster XIVa species specifically colonize mucins in an in vitro gut model
Abbeele, P. van den; Belzer, C. ; Goossens, M. ; Kleerebezem, M. ; Vos, W.M. de; Thas, O. ; Weirdt, R. de; Kerckhoffs, D.M.F.J. ; Wiele, T. van der - \ 2013
ISME Journal 7 (2013). - ISSN 1751-7362 - p. 949 - 961.
inflammatory-bowel-disease - phylogenetic microarray analysis - gel-electrophoresis analysis - mucosa-associated microbiota - human large-intestine - 16s ribosomal-rna - fecal microbiota - sp-nov. - gastrointestinal-tract - spatial-organization
The human gut is colonized by a complex microbiota with multiple benefits. Although the surface-attached, mucosal microbiota has a unique composition and potential to influence human health, it remains difficult to study in vivo. Therefore, we performed an in-depth microbial characterization (human intestinal tract chip (HITChip)) of a recently developed dynamic in vitro gut model, which simulates both luminal and mucosal gut microbes (mucosal-simulator of human intestinal microbial ecosystem (M-SHIME)). Inter-individual differences among human subjects were confirmed and microbial patterns unique for each individual were preserved in vitro. Furthermore, in correspondence with in vivo studies, Bacteroidetes and Proteobacteria were enriched in the luminal content while Firmicutes rather colonized the mucin layer, with Clostridium cluster XIVa accounting for almost 60% of the mucin-adhered microbiota. Of the many acetate and/or lactate-converting butyrate producers within this cluster, Roseburia intestinalis and Eubacterium rectale most specifically colonized mucins. These 16S rRNA gene-based results were confirmed at a functional level as butyryl-CoA:acetate-CoA transferase gene sequences belonged to different species in the luminal as opposed to the mucin-adhered microbiota, with Roseburia species governing the mucosal butyrate production. Correspondingly, the simulated mucosal environment induced a shift from acetate towards butyrate. As not only inter-individual differences were preserved but also because compared with conventional models, washout of relevant mucin-adhered microbes was avoided, simulating the mucosal gut microbiota represents a breakthrough in modeling and mechanistically studying the human intestinal microbiome in health and disease. Finally, as mucosal butyrate producers produce butyrate close to the epithelium, they may enhance butyrate bioavailability, which could be useful in treating diseases, such as inflammatory bowel disease
Emerging molecular insights into the interaction between probiotics and the host intestinal mucosa
Bron, P.A. ; Baarlen, P. van; Kleerebezem, M. - \ 2012
Nature Reviews Microbiology 10 (2012). - ISSN 1740-1526 - p. 66 - 78.
regulatory t-cells - lactobacillus-rhamnosus gg - human gut microbiome - toll-like receptor-2 - antibiotic-associated diarrhea - inflammatory-bowel-disease - placebo-controlled trial - tight junction proteins - murine dendritic cells - innate immune-system
Probiotic bacteria can modulate immune responses in the host gastrointestinal tract to promote health. The genomics era has provided novel opportunities for the discovery and characterization of bacterial probiotic effector molecules that elicit specific responses in the intestinal system. Furthermore, nutrigenomic analyses of the response to probiotics have unravelled the signalling and immune response pathways which are modulated by probiotic bacteria. Together, these genomic approaches and nutrigenomic analyses have identified several bacterial factors that are involved in modulation of the immune system and the mucosal barrier, and have revealed that a molecular 'bandwidth of human health' could represent a key determinant in an individual's physiological responsiveness to probiotics. These approaches may lead to improved stratification of consumers and to subpopulation-level probiotic supplementation to maintain or improve health, or to reduce the risk of disease