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Fasano A, Matera M. Probiotics to Prevent Celiac Disease and Inflammatory Bowel Diseases. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2024; 1449:95-111. [PMID: 39060733 DOI: 10.1007/978-3-031-58572-2_6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/28/2024]
Abstract
The incidence of chronic inflammatory diseases (CIDs) is dramatically increasing in the developed world, resulting in an increased burden of disease in childhood. Currently, there are limited effective strategies for treating or preventing these conditions. To date, myriads of cross-sectional studies have described alterations in the composition of the gut microbiota in a variety of disease states, after the disease has already occurred. We suggest that to mechanically link these microbiome changes with disease pathogenesis, a prospective cohort design is needed to capture changes that precede or coincide with disease onset and symptoms. In addition, these prospective studies must integrate microbiological, metagenomic, meta transcriptomic and metabolomic data with minimal and standardized clinical and environmental metadata that allow to correctly compare and interpret the results of the analysis of the human microbiota in order to build a system-level model of the interactions between the host and the development of the disease. The creation of new biological computational models thus constructed will allow us to finally move from the detection of simple elements of "association" to the identification of elements of real "causality" allowing to provide a mechanistic approach to the exploration of the development of CIDs.This can only be done when these diseases are studied as complex biological networks. In this chapter we discuss the current knowledge regarding the contribution of the microbiome to CID in childhood, focusing on celiac disease and inflammatory bowel disease, with the overall aim of identifying pathways to shift research from descriptive to mechanistic approaches. We then examine how some components of the microbiota, through epigenetic reprogramming, can start the march from genetic predisposition to clinical expression of CIDs, thus opening up new possibilities for intervention, through microbiota therapy targeting the manipulation of the composition and function of the microbiota, for future applications of precision medicine and primary prevention.
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Affiliation(s)
- Alessio Fasano
- Research Centre for Immunology and Mucosal Biology and Division of Pediatric Gastroenterology and Nutrition, Massachusetts General Hospital for Children - Harvard Medical School, Boston, USA, MA.
- Mucosal Immunology and Biology Research Center and Division of Pediatric Gastroenterology and Nutrition, Mass General for Children - Harvard Medical School, Boston, MA, USA.
| | - Mariarosaria Matera
- Neonatologist, Neurodevelopmental Clinics and Pediatric Clinical Microbiomic - Misericordia Hospital, Grosseto, Italy
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Serena G, Fasano A. Use of Probiotics to Prevent Celiac Disease and IBD in Pediatrics. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2018; 1125:69-81. [PMID: 30565165 DOI: 10.1007/5584_2018_317] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The incidence of chronic inflammatory diseases (CIDs) is increasing worldwide. Their dramatic rise associated with limited effective strategies to slow down these epidemics calls for a better understanding of their pathophysiology in order to decrease the burdens on childhood. Several cross-sectional studies have demonstrated the association between intestinal dysbiosis and active diseases. Although informative, these studies do not mechanistically link alterations of the microflora with disease pathogenesis and, therefore, with potential therapeutic targets. More prospective studies are needed to determine whether intestinal dysbiosis plays a causative role in the onset and development of CIDs. Furthermore, given the complexity of the microflora interaction with the host, it is necessary to design a systems-level model of interactions between the host and the development of disease by integrating microbiome, metagenomics, metatranscriptomics, and metabolomics with either clinical either environmental data.In this chapter we will discuss the current knowledge regarding the microbiome's contribution to celiac disease and inflammatory bowel disease with a particular focus on how probiotics may be used as potential preventive therapy for CIDs.
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Affiliation(s)
- Gloria Serena
- Mucosal Immunology and Biology Research Center and Division of Pediatric Gastroenterology and Nutrition, Massachusetts General Hospital for Children - Harvard Medical School, Boston, MA, USA.
| | - Alessio Fasano
- Mucosal Immunology and Biology Research Center and Division of Pediatric Gastroenterology and Nutrition, Massachusetts General Hospital for Children - Harvard Medical School, Boston, MA, USA
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Martin VJ, Leonard MM, Fiechtner L, Fasano A. Transitioning From Descriptive to Mechanistic Understanding of the Microbiome: The Need for a Prospective Longitudinal Approach to Predicting Disease. J Pediatr 2016; 179:240-248. [PMID: 27634626 PMCID: PMC5479769 DOI: 10.1016/j.jpeds.2016.08.049] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/03/2016] [Revised: 07/15/2016] [Accepted: 08/16/2016] [Indexed: 12/11/2022]
Affiliation(s)
| | | | | | - Alessio Fasano
- Department of Pediatric Gastroenterology and Nutrition, Massachusetts General Hospital for Children, Boston, MA.
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Wright EK, Kamm MA, Teo SM, Inouye M, Wagner J, Kirkwood CD. Recent advances in characterizing the gastrointestinal microbiome in Crohn's disease: a systematic review. Inflamm Bowel Dis 2015; 21:1219-28. [PMID: 25844959 PMCID: PMC4450900 DOI: 10.1097/mib.0000000000000382] [Citation(s) in RCA: 103] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/03/2015] [Accepted: 02/03/2015] [Indexed: 12/12/2022]
Abstract
BACKGROUND The intestinal microbiota is involved in the pathogenesis of inflammatory bowel disease. A reduction in the diversity of the intestinal microbiota as well as specific taxonomic and functional shifts have been reported in Crohn's disease and may play a central role in the inflammatory process. The aim was to systematically review recent developments in the structural and functional changes observed in the gastrointestinal microbiome in patients with Crohn's Disease. RESULTS Seventy-two abstracts were included in this review. The effects of host genetics, disease phenotype, and inflammatory bowel disease treatment on the gastrointestinal microbiome in Crohn's disease were reviewed, and taxonomic shifts in patients with early and established disease were described. The relative abundance of Bacteroidetes is increased and Firmicutes decreased in Crohn's disease compared with healthy controls. Enterobacteriaceae, specifically Eschericia coli, is enriched in Crohn's disease. Faecalibacterium prausnitzii is found at lower abundance in Crohn's disease and in those with postoperative recurrence. Observed functional changes include major shifts in oxidative stress pathways, a decrease in butanoate and propanoate metabolism gene expression, lower levels of butyrate, and other short-chain fatty acids, decreased carbohydrate metabolism, and decreased amino acid biosynthesis. CONCLUSIONS Changes in microbial composition and function have been described, although a causative role remains to be established. Larger, prospective, and longitudinal studies are required with deep interrogation of the microbiome if causality is to be determined, and refined microbial manipulation is to emerge as a focused therapy.
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Affiliation(s)
- Emily K. Wright
- Department of Gastroenterology, St Vincent's Hospital Melbourne, Australia
- Department of Pathology, University of Melbourne, Australia
| | - Michael A. Kamm
- Department of Gastroenterology, St Vincent's Hospital Melbourne, Australia
- Department of Pathology, University of Melbourne, Australia
- Imperial College, London, United Kingdom; and
| | - Shu Mei Teo
- Department of Pathology, University of Melbourne, Australia
| | - Michael Inouye
- Department of Pathology, University of Melbourne, Australia
| | - Josef Wagner
- Enteric Virus Group, Murdoch Children's Research Institute, Melbourne, Australia
| | - Carl D. Kirkwood
- Enteric Virus Group, Murdoch Children's Research Institute, Melbourne, Australia
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Stecher B, Berry D, Loy A. Colonization resistance and microbial ecophysiology: using gnotobiotic mouse models and single-cell technology to explore the intestinal jungle. FEMS Microbiol Rev 2013; 37:793-829. [PMID: 23662775 DOI: 10.1111/1574-6976.12024] [Citation(s) in RCA: 76] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2013] [Revised: 04/11/2013] [Accepted: 04/18/2013] [Indexed: 12/14/2022] Open
Abstract
The highly diverse intestinal microbiota forms a structured community engaged in constant communication with itself and its host and is characterized by extensive ecological interactions. A key benefit that the microbiota affords its host is its ability to protect against infections in a process termed colonization resistance (CR), which remains insufficiently understood. In this review, we connect basic concepts of CR with new insights from recent years and highlight key technological advances in the field of microbial ecology. We present a selection of statistical and bioinformatics tools used to generate hypotheses about synergistic and antagonistic interactions in microbial ecosystems from metagenomic datasets. We emphasize the importance of experimentally testing these hypotheses and discuss the value of gnotobiotic mouse models for investigating specific aspects related to microbiota-host-pathogen interactions in a well-defined experimental system. We further introduce new developments in the area of single-cell analysis using fluorescence in situ hybridization in combination with metabolic stable isotope labeling technologies for studying the in vivo activities of complex community members. These approaches promise to yield novel insights into the mechanisms of CR and intestinal ecophysiology in general, and give researchers the means to experimentally test hypotheses in vivo at varying levels of biological and ecological complexity.
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Affiliation(s)
- Bärbel Stecher
- Max von Pettenkofer Institute of Hygiene and Medical Microbiology, Ludwig-Maximilians-University of Munich, Munich, Germany.
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Tjellström B, Högberg L, Stenhammar L, Magnusson KE, Midtvedt T, Norin E, Sundqvist T. Effect of exclusive enteral nutrition on gut microflora function in children with Crohn's disease. Scand J Gastroenterol 2012; 47:1454-9. [PMID: 23016828 DOI: 10.3109/00365521.2012.703234] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
OBJECTIVE Exclusive enteral nutrition (EEN) is a first-line treatment in children with active Crohn's disease (CD) but is seldom used in adults with active disease. The mode of action of EEN in suppressing mucosal inflammation is not fully understood, but modulation of intestinal microflora activity is one possible explanation. The aim of this study was to investigate the effect of 6-week EEN in children with active CD, with special reference to intestinal microflora function. MATERIALS AND METHODS Fecal samples from 18 children (11 boys, 7 girls; median age 13.5 years) with active CD (13 children with small bowel/colonic and 5 with perianal disease) were analyzed for short chain fatty acid (SCFA) pattern as marker of gut microflora function. The children were studied before and after EEN treatment. Results from 12 healthy teenagers were used for comparison. RESULTS Eleven (79%) of the children with small bowel/colonic CD responded clinically positively to EEN treatment showing decreased levels of pro-inflammatory acetic acid as well as increased concentrations of anti-inflammatory butyric acids and also of valeric acids, similar to the levels in healthy age-matched children. In children with active perianal CD, however, EEN had no positive effect on clinical status or inflammatory parameters. CONCLUSIONS The authors present new data supporting the hypothesis that the well-documented anti-inflammatory effect of EEN in children with active small bowel/colonic CD is brought about by modulation of gut microflora activity, resulting in an anti-inflammatory SCFA pattern. By contrast, none of the children with perianal disease showed clinical or biochemical improvement after EEN treatment.
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Affiliation(s)
- Bo Tjellström
- Department of Microbiology, Karolinska Institute, Tumor and Cell Biology, Stockholm, Sweden.
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Hansom D, Littlejohn MG, Clancy MJ. Pyogenic ventriculitis following enteral bacterial translocation in a patient with small bowel obstruction. Scott Med J 2012; 57:60. [PMID: 22408220 DOI: 10.1258/smj.2011.011276] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The authors present a rare case of ventriculitis secondary to cerebro spinal fluid (CSF) colonization with Escherichia coli species in a 65-year-old woman. Passage of bacterial organisms from the lumen of the gastrointestinal tract to the bloodstream or lymphatic tissue is known as translocation. Once in the bloodstream, particular bacteria are able to cross the blood-brain barrier and migrate to CSF. Elective abdominal surgery, intestinal obstruction, colorectal cancer, ischaemic reperfusion injury and pancreatitis have all increased the risk of this phenomenon. This account highlights particular events in presentation and management of such a case, followed by a brief literature review.
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Affiliation(s)
- D Hansom
- Department of Surgery - Professorial Unit, Western Infirmary, Glasgow, Scotland, UK.
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Vermeiren J, Van den Abbeele P, Laukens D, Vigsnaes LK, De Vos M, Boon N, Van de Wiele T. Decreased colonization of fecal Clostridium coccoides/Eubacterium rectale species from ulcerative colitis patients in an in vitro dynamic gut model with mucin environment. FEMS Microbiol Ecol 2011; 79:685-96. [PMID: 22092917 DOI: 10.1111/j.1574-6941.2011.01252.x] [Citation(s) in RCA: 90] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2011] [Revised: 10/28/2011] [Accepted: 11/02/2011] [Indexed: 12/16/2022] Open
Abstract
The mucus layer in the colon, acting as a barrier to prevent invasion of pathogens, is thinner and discontinuous in patients with ulcerative colitis (UC). A recent developed in vitro dynamic gut model, the M-SHIME, was used to compare long-term colonization of the mucin layer by the microbiota from six healthy volunteers (HV) and six UC patients and thus distinguish the mucin adhered from the luminal microbiota. Although under the same nutritional conditions, short-chain fatty acid production by the luminal communities from UC patients showed a tendency toward a lower butyrate production. A more in-depth community analysis of those microbial groups known to produce butyrate revealed that the diversity of the Clostridium coccoides/Eubacterium rectale and Clostridium leptum group, and counts of Faecalibacterium prausnitzii were lower in the luminal fractions of the UC samples. Counts of Roseburia spp. were lower in the mucosal fractions of the UC samples. qPCR analysis for butyryl-CoA:acetate CoA transferase, responsible for butyrate production, displayed a lower abundance in both the luminal and mucosal fractions of the UC samples. The M-SHIME model revealed depletion in butyrate producing microbial communities not restricted to the luminal but also in the mucosal samples from UC patients compared to HV.
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Affiliation(s)
- Joan Vermeiren
- Laboratory of Microbial Ecology and Technology, Ghent University, Gent, Belgium
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Use of stable isotopes to measure the metabolic activity of the human intestinal microbiota. Appl Environ Microbiol 2011; 77:8009-14. [PMID: 21948826 DOI: 10.1128/aem.05573-11] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The human intestinal microbiota is a complex biological system comprising a vast repertoire of microbes with considerable metabolic activity relevant to both bacterial growth and host health. Greater strides have been made in the analysis of microbial diversity than in the measurement of functional activity, particularly in vivo. Stable isotope probing offers a new approach by coupling measurements of metabolic activity with microbial identification. Using a low-enrichment labeling strategy in vitro, this study has identified metabolically active bacterial groups via magnetic-bead capture methodology and stable isotope ratio analysis. Using five probes (EUB338, Bac303, Bif164, EREC482, and Clep866), changes in the activities of key intestinal microbial groups were successfully measured by exploiting tracers of de novo RNA synthesis. Perturbation of the nutrient source with oligofructose generated changes in the activity of bifidobacteria as expected, but also in the Bacteroides-Prevotella group, the Eubacterium rectale-Clostridium coccoides group, and the Clostridium leptum subgroup. Changes in activity were also observed in response to the medium type. This study suggests that changes in the functional activity of the gut microbiota can be assessed using tracers of de novo nucleic acid synthesis combined with measurement of low isotopic enrichment in 16S rRNA. Such tracers potentially limit substrate bias because they are universally available to bacteria. This low-enrichment labeling approach does not depend on the commercial availability of specific labeled substrates and can be easily translated to in vivo probing experiments of the functional activity of the microbiota in the human gut.
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Horz HP, Conrads G. Methanogenic Archaea and oral infections - ways to unravel the black box. J Oral Microbiol 2011; 3. [PMID: 21541092 PMCID: PMC3086593 DOI: 10.3402/jom.v3i0.5940] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2010] [Revised: 01/25/2011] [Accepted: 01/26/2011] [Indexed: 02/06/2023] Open
Abstract
Archaea, organisms that make up the third domain of cellular life are members of the human oral microflora. They are strikingly less diverse than oral bacteria and appear to be relatively rare with respect to their numerical abundance. Since they have been exclusively found in association with oral infections such as periodontitis and apical periodontitis and given their unique physiology and energy metabolism, it is highly plausible that they are more than just secondary colonizers of infected areas, but instead are actively involved in the overall poly-microbial infection process. Conversely, it is a highly challenging task to clearly demonstrate their possible active participation – mostly due to the difficulty to grow them in routine microbiology laboratories. This current review points out the importance for understanding the medical impact of methanogens and aims at devising strategies for elucidating the true function of archaea in the oral ecosystem.
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Affiliation(s)
- Hans-Peter Horz
- Division of Oral Microbiology and Immunology, RWTH Aachen University Hospital, Aachen, Germany
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van Ommen B, El-Sohemy A, Hesketh J, Kaput J, Fenech M, Evelo CT, McArdle HJ, Bouwman J, Lietz G, Mathers JC, Fairweather-Tait S, van Kranen H, Elliott R, Wopereis S, Ferguson LR, Méplan C, Perozzi G, Allen L, Rivero D. The Micronutrient Genomics Project: a community-driven knowledge base for micronutrient research. GENES AND NUTRITION 2010; 5:285-96. [PMID: 21189865 PMCID: PMC2989004 DOI: 10.1007/s12263-010-0192-8] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/17/2010] [Accepted: 10/13/2010] [Indexed: 01/19/2023]
Abstract
Micronutrients influence multiple metabolic pathways including oxidative and inflammatory processes. Optimum micronutrient supply is important for the maintenance of homeostasis in metabolism and, ultimately, for maintaining good health. With advances in systems biology and genomics technologies, it is becoming feasible to assess the activity of single and multiple micronutrients in their complete biological context. Existing research collects fragments of information, which are not stored systematically and are thus not optimally disseminated. The Micronutrient Genomics Project (MGP) was established as a community-driven project to facilitate the development of systematic capture, storage, management, analyses, and dissemination of data and knowledge generated by biological studies focused on micronutrient–genome interactions. Specifically, the MGP creates a public portal and open-source bioinformatics toolbox for all “omics” information and evaluation of micronutrient and health studies. The core of the project focuses on access to, and visualization of, genetic/genomic, transcriptomic, proteomic and metabolomic information related to micronutrients. For each micronutrient, an expert group is or will be established combining the various relevant areas (including genetics, nutrition, biochemistry, and epidemiology). Each expert group will (1) collect all available knowledge, (2) collaborate with bioinformatics teams towards constructing the pathways and biological networks, and (3) publish their findings on a regular basis. The project is coordinated in a transparent manner, regular meetings are organized and dissemination is arranged through tools, a toolbox web portal, a communications website and dedicated publications.
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Affiliation(s)
- Ben van Ommen
- TNO Quality of Life, P.O. box 360, 3700 AJ Zeist, The Netherlands
| | - Ahmed El-Sohemy
- Department of Nutritional Sciences, University of Toronto, 150 College Street, Toronto, ON M5S 3E2 Canada
| | - John Hesketh
- Institute for Cell and Molecular Biosciences, Newcastle University Medical School and Human Nutrition Research Centre, Newcastle-upon-Tyne, NE2 4HH UK
| | - Jim Kaput
- Division of Personalized Nutrition and Medicine, National Center for Toxicological Research, Food and Drug Administration, 3900 NCTR Road, Jefferson, AR 72079 USA
| | - Michael Fenech
- CSIRO Food and Nutritional Sciences, PO Box 10041, Adelaide BC, SA 5000 Australia
| | - Chris T. Evelo
- Department of Bioinformatics—BiGCaT, Maastricht University, Maastricht, The Netherlands
| | - Harry J. McArdle
- Rowett Institute of Nutrition and Health, University of Aberdeen, Aberdeen, AB21 9SB UK
| | - Jildau Bouwman
- TNO Quality of Life, P.O. box 360, 3700 AJ Zeist, The Netherlands
| | - Georg Lietz
- Human Nutrition Research Centre, School of Agriculture, Food and Rural Development, Newcastle University, Kings Road, Agriculture Building, Newcastle upon Tyne, NE1 7RU UK
| | - John C. Mathers
- Human Nutrition Research Centre, Institute for Ageing and Health, Newcastle University, Newcastle upon Tyne, NE2 4HH UK
| | - Sue Fairweather-Tait
- School of Medicine, Health Policy and Practice, University of East Anglia, Norwich, NR4 7TJ UK
| | | | - Ruan Elliott
- Institute of Food Research, Norwich Research Park, Norwich, NR4 7UA UK
| | - Suzan Wopereis
- TNO Quality of Life, P.O. box 360, 3700 AJ Zeist, The Netherlands
| | - Lynnette R. Ferguson
- Discipline of Nutrition, Faculty of Medical and Health Sciences, The University of Auckland, Auckland, New Zealand
| | - Catherine Méplan
- Institute for Cell and Molecular Biosciences, Newcastle University Medical School and Human Nutrition Research Centre, Newcastle-upon-Tyne, NE2 4HH UK
| | - Giuditta Perozzi
- Department of Nutritional Sciences—INRAN, National Research Institute on Food & Nutrition, Via Ardeatina 546, 00178 Rome, Italy
| | - Lindsay Allen
- USDA, ARS Western Human Nutrition Research Center, University of California, 530 W. Health Sciences Drive, Davis, CA 95616 USA
| | - Damariz Rivero
- Department of Pharmacology, University of Florence, Viale Pieraccini 6, 50139 Florence, Italy
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McCullagh JSO. Mixed-mode chromatography/isotope ratio mass spectrometry. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2010; 24:483-494. [PMID: 20162548 DOI: 10.1002/rcm.4322] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Liquid chromatography coupled to molecular mass spectrometry (LC/MS) has been a standard technique since the early 1970s but liquid chromatography coupled to high-precision isotope ratio mass spectrometry (LC/IRMS) has only been available commercially since 2004. This development has, for the first time, enabled natural abundance and low enrichment delta(13)C measurements to be applied to individual analytes in aqueous mixtures creating new opportunities for IRMS applications, particularly for the isotopic study of biological molecules. A growing number of applications have been published in a range of areas including amino acid metabolism, carbohydrates studies, quantification of cellular and plasma metabolites, dietary tracer and nucleic acid studies. There is strong potential to extend these to new compounds and complex matrices but several challenges face the development of LC/IRMS methods. To achieve accurate isotopic measurements, HPLC separations must provide baseline-resolution between analyte peaks; however, the design of current liquid interfaces places severe restrictions on compatible flow rates and in particular mobile phase compositions. These create a significant challenge on which reports associated with LC/IRMS have not previously focused. Accordingly, this paper will address aspects of chromatography in the context of LC/IRMS, in particular focusing on mixed-mode separations and their benefits in light of these restrictions. It aims to provide an overview of mixed-mode stationary phases and of ways to improve high aqueous separations through manipulation of parameters such as column length, temperature and mobile phase pH. The results of several practical experiments are given using proteogenic amino acids and nucleosides both of which are of noted importance in the LC/IRMS literature. This communication aims to demonstrate that mixed-mode stationary phases provide a flexible approach given the constraints of LC/IRMS interface design and acts as a practical guide for the development of new chromatographic methods compatible with LC/IRMS applications.
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Affiliation(s)
- James S O McCullagh
- Chemistry Research Laboratory, University of Oxford, Mansfield Rd, Oxford OX1 3TA, UK.
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The involvement of heat-shock proteins in the pathogenesis of autoimmune arthritis: a critical appraisal. Semin Arthritis Rheum 2009; 40:164-75. [PMID: 19969325 DOI: 10.1016/j.semarthrit.2009.10.002] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2009] [Revised: 09/23/2009] [Accepted: 10/04/2009] [Indexed: 01/31/2023]
Abstract
OBJECTIVES To review the literature on the role of heat-shock proteins (HSPs) in the pathogenesis of autoimmune arthritis in animal models and patients with rheumatoid arthritis (RA). METHODS The published literature in Medline (PubMed), including our published work on the cell-mediated as well as humoral immune response to various HSPs, was reviewed. Studies in the preclinical animal models of arthritis as well as RA were examined critically and the data are presented. RESULTS In experimental arthritis, disease induction by different arthritogenic stimuli, including an adjuvant, led to immune response to mycobacterial HSP65 (BHSP65). However, attempts to induce arthritis by a purified HSP have not met with success. There are several reports of a significant immune response to HSP65 in RA patients. However, the issue of cause and effect is difficult to address. Nevertheless, several studies in animal models and a couple of clinical trials in RA patients have shown the beneficial effect of HSPs against autoimmune arthritis. CONCLUSIONS There is a clear association between immune response to HSPs, particularly HSP65, and the initiation and propagation of autoimmune arthritis in experimental models. The correlation is relatively less convincing in RA patients. In both cases, the ability of HSPs to modulate arthritis offers support, albeit an indirect one, for the involvement of these antigens in the disease process.
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Barclay AR, Russell RK, Wilson ML, Gilmour WH, Satsangi J, Wilson DC. Systematic review: the role of breastfeeding in the development of pediatric inflammatory bowel disease. J Pediatr 2009; 155:421-6. [PMID: 19464699 DOI: 10.1016/j.jpeds.2009.03.017] [Citation(s) in RCA: 138] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/27/2008] [Revised: 01/13/2009] [Accepted: 03/10/2009] [Indexed: 02/08/2023]
Abstract
OBJECTIVES To assess the current evidence for the role of breastfeeding in the development of early onset inflammatory bowel disease (IBD) with a systematic review. STUDY DESIGN An electronic database search was performed (January 1966-January 2008) with keywords related to IBD and breastfeeding, looking specifically for studies that reported outcome in early-onset disease (<16 years of age) and "any exposure" to breast milk as the variables. Meta-analysis of studies included for review was then performed by using a random effects model, and results were expressed as odds ratios (OR) with 95% CIs. RESULTS A total of 79 articles were identified, 20 of which were found describing breastfeeding in relation to the development of IBD; 8 of these articles included separate early-onset groups. One study did not describe "any exposure" to breast milk for the early onset group, so 7 studies were included in the meta-analysis. Breast milk exposure had a significant protective effect (OR, 0.69; 95% CI, 0.51-0.94; P = .02) in developing early-onset IBD. A non-significant difference was demonstrated for ulcerative colitis and Crohn's disease individually (OR, 0.72; 95% CI, 0.51-1.02; P = .06; OR, 0.64; 95% CI, 0.38-1.07; P = .09, respectively). CONCLUSIONS The current evidence demonstrates a possible protective effect for breast milk in the development of early onset IBD. However, the quality of existing data is generally poor. These findings need to be investigated in well-designed prospective studies.
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Dong Y, Manfredini F, Dimopoulos G. Implication of the mosquito midgut microbiota in the defense against malaria parasites. PLoS Pathog 2009; 5:e1000423. [PMID: 19424427 PMCID: PMC2673032 DOI: 10.1371/journal.ppat.1000423] [Citation(s) in RCA: 525] [Impact Index Per Article: 35.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2009] [Accepted: 04/09/2009] [Indexed: 01/20/2023] Open
Abstract
Malaria-transmitting mosquitoes are continuously exposed to microbes, including their midgut microbiota. This naturally acquired microbial flora can modulate the mosquito's vectorial capacity by inhibiting the development of Plasmodium and other human pathogens through an unknown mechanism. We have undertaken a comprehensive functional genomic approach to elucidate the molecular interplay between the bacterial co-infection and the development of the human malaria parasite Plasmodium falciparum in its natural vector Anopheles gambiae. Global transcription profiling of septic and aseptic mosquitoes identified a significant subset of immune genes that were mostly up-regulated by the mosquito's microbial flora, including several anti-Plasmodium factors. Microbe-free aseptic mosquitoes displayed an increased susceptibility to Plasmodium infection while co-feeding mosquitoes with bacteria and P. falciparum gametocytes resulted in lower than normal infection levels. Infection analyses suggest the bacteria-mediated anti-Plasmodium effect is mediated by the mosquitoes' antimicrobial immune responses, plausibly through activation of basal immunity. We show that the microbiota can modulate the anti-Plasmodium effects of some immune genes. In sum, the microbiota plays an essential role in modulating the mosquito's capacity to sustain Plasmodium infection. The Anopheles gambiae mosquito that transmits the malaria-causing parasite Plasmodium has an intestinal bacterial flora, or microbiota, which comprises a variety of species. Elimination of this microbiota with antibiotic treatment will render the Anopheles mosquito more susceptible to Plasmodium infection. In this study we show that these bacteria can inhibit the infection of the mosquito with the human malaria parasite Plasmodium falciparum through a mechanism that involves the mosquito's immune system. Our study suggests that the microbial flora of mosquitoes is stimulating a basal immune activity, which comprises several factors with known anti-Plasmodium activity. The same immune factors that are needed to control the mosquito's microbiota are also defending against the malaria parasite Plasmodium. This complex interplay among the mosquito's microbiota, the innate immune system, and the Plasmodium parasite may have significant implications for the transmission of malaria in the field where the bacterial exposure of mosquitoes may differ greatly between ecological niches.
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Affiliation(s)
- Yuemei Dong
- W. Harry Feinstone Department of Molecular Microbiology and Immunology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, Maryland, United States of America
| | - Fabio Manfredini
- W. Harry Feinstone Department of Molecular Microbiology and Immunology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, Maryland, United States of America
| | - George Dimopoulos
- W. Harry Feinstone Department of Molecular Microbiology and Immunology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, Maryland, United States of America
- * E-mail:
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