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Vidal-Veuthey B, González D, Cárdenas JP. Role of microbial secreted proteins in gut microbiota-host interactions. Front Cell Infect Microbiol 2022; 12:964710. [PMID: 35967863 PMCID: PMC9373040 DOI: 10.3389/fcimb.2022.964710] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Accepted: 07/06/2022] [Indexed: 11/30/2022] Open
Abstract
The mammalian gut microbiota comprises a variety of commensals including potential probiotics and pathobionts, influencing the host itself. Members of the microbiota can intervene with host physiology by several mechanisms, including the secretion of a relatively well-reported set of metabolic products. Another microbiota influence mechanism is the use of secreted proteins (i.e., the secretome), impacting both the host and other community members. While widely reported and studied in pathogens, this mechanism remains understood to a lesser extent in commensals, and this knowledge is increasing in recent years. In the following minireview, we assess the current literature covering different studies, concerning the functions of secretable proteins from members of the gut microbiota (including commensals, pathobionts, and probiotics). Their effect on host physiology and health, and how these effects can be harnessed by postbiotic products, are also discussed.
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Affiliation(s)
- Boris Vidal-Veuthey
- Centro de Genómica y Bioinformática, Facultad de Ciencias, Ingeniería y Tecnología, Universidad Mayor, Huechuraba, Chile
| | - Dámariz González
- Centro de Genómica y Bioinformática, Facultad de Ciencias, Ingeniería y Tecnología, Universidad Mayor, Huechuraba, Chile
| | - Juan P. Cárdenas
- Centro de Genómica y Bioinformática, Facultad de Ciencias, Ingeniería y Tecnología, Universidad Mayor, Huechuraba, Chile
- Escuela de Biotecnología, Facultad de Ciencias, Ingeniería y Tecnología, Universidad Mayor, Santiago, Chile
- *Correspondence: Juan P. Cárdenas,
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2
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Xia P, Lian S, Wu Y, Yan L, Quan G, Zhu G. Zinc is an important inter-kingdom signal between the host and microbe. Vet Res 2021; 52:39. [PMID: 33663613 PMCID: PMC7931793 DOI: 10.1186/s13567-021-00913-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2020] [Accepted: 02/08/2021] [Indexed: 12/15/2022] Open
Abstract
Zinc (Zn) is an essential trace element in living organisms and plays a vital role in the regulation of both microbial virulence and host immune responses. A growing number of studies have shown that zinc deficiency or the internal Zn concentration does not meet the needs of animals and microbes, leading to an imbalance in zinc homeostasis and intracellular signalling pathway dysregulation. Competition for zinc ions (Zn2+) between microbes and the host exists in the use of Zn2+ to maintain cell structure and physiological functions. It also affects the interplay between microbial virulence factors and their specific receptors in the host. This review will focus on the role of Zn in the crosstalk between the host and microbe, especially for changes in microbial pathogenesis and nociceptive neuron-immune interactions, as it may lead to new ways to prevent or treat microbial infections.
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Affiliation(s)
- Pengpeng Xia
- College of Veterinary Medicine (Institute of Comparative Medicine), Yangzhou University, Yangzhou, 225009, China. .,Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, 225009, China. .,Joint International Research Laboratory of Agriculture and Agri-Product Safety of Ministry of Education of China, Yangzhou University, Yangzhou, 225009, China.
| | - Siqi Lian
- College of Veterinary Medicine (Institute of Comparative Medicine), Yangzhou University, Yangzhou, 225009, China.,Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, 225009, China.,Joint International Research Laboratory of Agriculture and Agri-Product Safety of Ministry of Education of China, Yangzhou University, Yangzhou, 225009, China
| | - Yunping Wu
- College of Veterinary Medicine (Institute of Comparative Medicine), Yangzhou University, Yangzhou, 225009, China.,Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, 225009, China.,Joint International Research Laboratory of Agriculture and Agri-Product Safety of Ministry of Education of China, Yangzhou University, Yangzhou, 225009, China
| | - Li Yan
- College of Veterinary Medicine (Institute of Comparative Medicine), Yangzhou University, Yangzhou, 225009, China.,Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, 225009, China.,Joint International Research Laboratory of Agriculture and Agri-Product Safety of Ministry of Education of China, Yangzhou University, Yangzhou, 225009, China
| | - Guomei Quan
- College of Veterinary Medicine (Institute of Comparative Medicine), Yangzhou University, Yangzhou, 225009, China.,Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, 225009, China.,Joint International Research Laboratory of Agriculture and Agri-Product Safety of Ministry of Education of China, Yangzhou University, Yangzhou, 225009, China
| | - Guoqiang Zhu
- College of Veterinary Medicine (Institute of Comparative Medicine), Yangzhou University, Yangzhou, 225009, China. .,Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, 225009, China. .,Joint International Research Laboratory of Agriculture and Agri-Product Safety of Ministry of Education of China, Yangzhou University, Yangzhou, 225009, China.
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3
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Jeffrey MP, MacPherson CW, Mathieu O, Tompkins TA, Green-Johnson JM. Secretome-Mediated Interactions with Intestinal Epithelial Cells: A Role for Secretome Components from Lactobacillus rhamnosus R0011 in the Attenuation of Salmonella enterica Serovar Typhimurium Secretome and TNF-α-Induced Proinflammatory Responses. THE JOURNAL OF IMMUNOLOGY 2020; 204:2523-2534. [PMID: 32238458 DOI: 10.4049/jimmunol.1901440] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2019] [Accepted: 02/26/2020] [Indexed: 12/13/2022]
Abstract
Recent evidence suggests that lactic acid bacteria communicate with host cells via secretome components to influence immune responses but less is known about gut-pathogen secretomes, impact of lactic acid bacteria secretomes on host-pathogen interactions, and the mechanisms underlying these interactions. Genome-wide microarrays and cytokine profiling were used to interrogate the impact of the Lactobacillus rhamnosus R0011 secretome (LrS) on TNF-α and Salmonella enterica subsp. enterica serovar Typhimurium secretome (STS)-induced outcomes in human intestinal epithelial cells. The LrS attenuated both TNF-α- and STS-induced gene expression involved in NF-κB and MAPK activation, as well as expression of genes involved in other immune-related signaling pathways. Specifically, the LrS induced the expression of dual specificity phosphatase 1 (DUSP1), activating transcription factor 3 (ATF3), and tribbles pseudokinase 3 (TRIB3), negative regulators of innate immune signaling, in HT-29 intestinal epithelial cells challenged with TNF-α or STS. TNF-α- and STS-induced acetylation of H3 and H4 histones was attenuated by the LrS, as was the production of TNF-α- and STS-induced proinflammatory cytokines and chemokines. Interestingly, the LrS induced production of macrophage migration inhibitory factor (MIF), a cytokine involved in host-microbe interactions at the gut interface. We propose that the LrS attenuates proinflammatory mediator expression through increased transcription of negative regulators of innate immune activity and changes in global H3 and H4 histone acetylation. To our knowledge, these findings provide novel insights into the complex multifaceted mechanisms of action behind secretome-mediated interdomain communication at the gut-mucosal interface.
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Affiliation(s)
- Michael P Jeffrey
- Applied Bioscience Graduate Program and the Faculty of Science, Ontario Technical University, Oshawa, Ontario L1G 0C5, Canada; and
| | - Chad W MacPherson
- Rosell Institute for Microbiome and Probiotics, Montreal, Quebec H4P 2R2, Canada
| | - Olivier Mathieu
- Rosell Institute for Microbiome and Probiotics, Montreal, Quebec H4P 2R2, Canada
| | - Thomas A Tompkins
- Rosell Institute for Microbiome and Probiotics, Montreal, Quebec H4P 2R2, Canada
| | - Julia M Green-Johnson
- Applied Bioscience Graduate Program and the Faculty of Science, Ontario Technical University, Oshawa, Ontario L1G 0C5, Canada; and
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4
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Jeffrey MP, Strap JL, Jones Taggart H, Green-Johnson JM. Suppression of Intestinal Epithelial Cell Chemokine Production by Lactobacillus rhamnosus R0011 and Lactobacillus helveticus R0389 Is Mediated by Secreted Bioactive Molecules. Front Immunol 2018; 9:2639. [PMID: 30524427 PMCID: PMC6262363 DOI: 10.3389/fimmu.2018.02639] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2018] [Accepted: 10/26/2018] [Indexed: 12/21/2022] Open
Abstract
Host intestinal epithelial cells (IEC) present at the gastrointestinal interface are exposed to pathogenic and non-pathogenic bacteria and their products. Certain probiotic lactic acid bacteria (LAB) have been associated with a range of host-immune modulatory activities including down-regulation of pro-inflammatory gene expression and cytokine production by IEC, with growing evidence suggesting that these bacteria secrete bioactive molecules with immunomodulatory activity. The aim of this study was to determine whether two lactobacilli with immunomodulatory activity [Lactobacillus rhamnosus R0011 (Lr) and Lactobacillus helveticus R0389 (Lh)], produce soluble mediators able to influence IEC responses to Pattern Recognition Receptor (PRR) ligands and pro-inflammatory cytokines [Tumor Necrosis Factor α (TNFα), Interleukin-1β (IL-1β)], signals inducing IEC chemokine production during infection. To this end, the effects of cell-free supernatants (CFS) from Lr and Lh on IEC production of the pro-inflammatory chemokines interleukin (IL)-8 and cytokine-induced neutrophil chemoattractant 1 (CINC-1) induced by a range of host- or pathogen-derived pro-inflammatory stimuli were determined, and the impact on human HT-29 IEC and a primary IEC line (rat IEC-6) was compared. The Lr-CFS and Lh-CFS did not significantly modulate basal IL-8 production from HT-29 IECs or CINC-1 production from IEC-6 cells. However, both Lr-CFS and Lh-CFS significantly down-regulated IL-8 production from HT-29 IECs challenged with varied PRR ligands. Lr-CFS and Lh-CFS had differential effects on PRR-induced CINC-1 production by rat IEC-6 IECs, with no significant down-regulation of CINC-1 observed from IEC-6 IECs cultured with Lh-CFS. Further analysis of the Lr-CFS revealed down-regulation of IL-8 production induced by the pro-inflammatory cytokines IL-1β and TNFα Preliminary characterization of the bioactive constituent(s) of the Lr-CFS indicates that it is resistant to treatment with DNase, RNase, and an acidic protease, but is sensitive to alterations in pH. Taken together, these results indicate that these lactobacilli secrete bioactive molecules of low molecular weight that may modulate host innate immune activity through interactions with IEC.
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Affiliation(s)
- Michael P Jeffrey
- Applied Bioscience Graduate Program, University of Ontario Institute of Technology, Oshawa, ON, Canada
| | - Janice L Strap
- Applied Bioscience Graduate Program, University of Ontario Institute of Technology, Oshawa, ON, Canada.,Faculty of Science, University of Ontario Institute of Technology, Oshawa, ON, Canada
| | - Holly Jones Taggart
- Applied Bioscience Graduate Program, University of Ontario Institute of Technology, Oshawa, ON, Canada.,Faculty of Health Sciences, University of Ontario Institute of Technology, Oshawa, ON, Canada
| | - Julia M Green-Johnson
- Applied Bioscience Graduate Program, University of Ontario Institute of Technology, Oshawa, ON, Canada.,Faculty of Science, University of Ontario Institute of Technology, Oshawa, ON, Canada
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5
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Abstract
Osteoporosis, characterized by low bone mass and micro-architectural deterioration of bone tissue with increased risk of fracture, can be categorized into two forms: primary and secondary, depending on whether it occurs as part of the natural aging process (estrogen deficiency) or as part of disease pathology. In both forms bone loss is due to an imbalance in the bone remodeling process, with resorption/formation skewed more toward bone loss. Recent studies and emerging evidence consistently demonstrate the potential of the intestinal microbiota to modulate bone health. This review discusses the process of bone remodeling and the pathology of osteoporosis and introduces the intestinal microbiota and its potential to influence bone health. In particular, we highlight recent murine studies that examine how probiotic supplementation can both increase bone density in healthy individuals and protect against primary (estrogen deficiency) as well as secondary osteoporosis. Potential mechanisms are described to account for how probiotic treatments could be exerting their beneficial effect on bone health.
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6
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Meng D, Zhu W, Ganguli K, Shi HN, Walker WA. Anti-inflammatory effects of Bifidobacterium longum subsp infantis secretions on fetal human enterocytes are mediated by TLR-4 receptors. Am J Physiol Gastrointest Liver Physiol 2016; 311:G744-G753. [PMID: 27562058 PMCID: PMC5142200 DOI: 10.1152/ajpgi.00090.2016] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/01/2016] [Accepted: 08/17/2016] [Indexed: 01/31/2023]
Abstract
The therapeutic and preventive application of probiotics for necrotizing enterocolitis (NEC) has been supported by more and more experimental and clinical evidence in which Toll-like receptor 4 (TLR-4) exerts a significant role. In immune cells, probiotics not only regulate the expression of TLR-4 but also use the TLR-4 to modulate the immune response. Probiotics may also use the TLR-4 in immature enterocytes for anti-inflammation. Here we demonstrate that probiotic conditioned media (PCM) from Bifidobacterium longum supp infantis but not isolated organisms attenuates interleukin-6 (IL-6) induction in response to IL-1β by using TLR-4 in a human fetal small intestinal epithelial cell line (H4 cells), human fetal small intestinal xenografts, mouse fetal small intestinal organ culture tissues, and primary NEC enterocytes. Furthermore, we show that PCM, using TLR-4, downregulates the mRNA expression of interleukin-1 receptor-associated kinase 2 (IRAK-2), a common adapter protein shared by IL-1β and TLR-4 signaling. PCM also reduces the phosphorylation of the activator-protein 1 (AP-1) transcription factors c-Jun and c-Fos in response to IL-1β stimulation in a TLR-4-dependent manner. This study suggests that PCM may use TLR-4 through IRAK-2 and via AP-1 to prevent IL-1β-induced IL-6 induction in immature enterocytes. Based on these observations, the combined use of probiotics and anti-TLR-4 therapy to prevent NEC may not be a good strategy.
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Affiliation(s)
- Di Meng
- Mucosal Immunology and Biology Research Center, Massachusetts General Hospital for Children, Harvard Medical School, Boston, Massachusetts
| | - Weishu Zhu
- Mucosal Immunology and Biology Research Center, Massachusetts General Hospital for Children, Harvard Medical School, Boston, Massachusetts
| | - Kriston Ganguli
- Mucosal Immunology and Biology Research Center, Massachusetts General Hospital for Children, Harvard Medical School, Boston, Massachusetts
| | - Hai Ning Shi
- Mucosal Immunology and Biology Research Center, Massachusetts General Hospital for Children, Harvard Medical School, Boston, Massachusetts
| | - W Allan Walker
- Mucosal Immunology and Biology Research Center, Massachusetts General Hospital for Children, Harvard Medical School, Boston, Massachusetts
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7
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GAO JISHENG, WU HONGWEI, LIU JINFENG. Importance of gut microbiota in health and diseases of new born infants. Exp Ther Med 2016; 12:28-32. [PMID: 27347013 PMCID: PMC4906629 DOI: 10.3892/etm.2016.3253] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2015] [Accepted: 04/11/2016] [Indexed: 12/21/2022] Open
Abstract
The multifarious assortment of microorganisms present in gut of humans is termed as gut microbiota. These include 1,000 species accompanied by approximately 2 million genes in an individual adult. The gut microbiota has multifactorial protective roles against allergic reactions, inflammation, cardiac pathological states and even in the state of malignant carcinogenesis existing in humans. By contrast, adverse alterations in the microbiota result in chronic pathological states, including autoimmune diseases, cancer and circulatory system obstructions. Gut bacteria also maintain sensitivity towards nutritional changes as well as antibiotics. The present review article focused on the importance of gut bacteria in newborn infants with special reference to their protective role in various pediatric pathological states linked with gut bacteria. In addition, the importance of probiotics in relation to gut microbiota are to be discussed.
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Affiliation(s)
- JISHENG GAO
- Department of Neonatology, Xuzhou Chlidren's Hospital, Xuzhou, Jiangsu 221002, P.R. China
| | - HONGWEI WU
- Department of Neonatology, Xuzhou Chlidren's Hospital, Xuzhou, Jiangsu 221002, P.R. China
| | - JINFENG LIU
- Department of Neonatology, Xuzhou Chlidren's Hospital, Xuzhou, Jiangsu 221002, P.R. China
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8
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Dimitrovski D, Cencič A, Winkelhausen E, Langerholc T. Lactobacillus plantarum extracellular metabolites: In vitro assessment of probiotic effects on normal and cancerogenic human cells. Int Dairy J 2014. [DOI: 10.1016/j.idairyj.2014.07.009] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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9
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Brosnahan AJ, Merriman JA, Salgado-Pabón W, Ford B, Schlievert PM. Enterococcus faecalis inhibits superantigen toxic shock syndrome toxin-1-induced interleukin-8 from human vaginal epithelial cells through tetramic acids. PLoS One 2013; 8:e61255. [PMID: 23613823 PMCID: PMC3632545 DOI: 10.1371/journal.pone.0061255] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2011] [Accepted: 03/11/2013] [Indexed: 11/18/2022] Open
Abstract
The vaginal mucosa can be colonized by many bacteria including commensal organisms and potential pathogens, such as Staphylococcus aureus. Some strains of S. aureus produce the superantigen toxic shock syndrome toxin-1, which can penetrate the vaginal epithelium to cause toxic shock syndrome. We have observed that a female was mono-colonized with Enterococcus faecalis vaginally as tested in aerobic culture, even upon repeated culture for six months, suggesting this organism was negatively influencing colonization by other bacteria. In recent studies, we demonstrated an "outside-in" mechanism of cytokine signaling and consequent inflammation that facilitates the ability of potential pathogens to initiate infection from mucosal surfaces. Thus, we hypothesized that this strain of E. faecalis may make anti-inflammatory factors which block disease progression of more pathogenic organisms. E. faecalis MN1 inhibited interleukin-8 production from human vaginal epithelial cells in response to the vaginal pathogens Candida albicans, Gardnerella vaginalis, and Neisseria gonorrhoeae, as well as to toxic shock syndrome toxin-1. We further demonstrated that this organism secretes two tetramic acid compounds which appear responsible for inhibition of interleukin-8 production, as well as inhibition of T cell proliferation due to toxic shock syndrome toxin-1. Microbicides that include anti-inflammatory molecules, such as these tetramic acid compounds naturally produced by E. faecalis MN1, may be useful in prevention of diseases that develop from vaginal infections.
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Affiliation(s)
- Amanda J. Brosnahan
- Department of Microbiology, University of Minnesota Medical School, Minneapolis, Minnesota, United States of America
| | - Joseph A. Merriman
- Department of Microbiology, University of Iowa Carver College of Medicine, Iowa City, Iowa, United States of America
| | - Wilmara Salgado-Pabón
- Department of Microbiology, University of Iowa Carver College of Medicine, Iowa City, Iowa, United States of America
| | - Bradley Ford
- Department of Pathology, University of Iowa Carver College of Medicine, Iowa City, Iowa, United States of America
| | - Patrick M. Schlievert
- Department of Microbiology, University of Minnesota Medical School, Minneapolis, Minnesota, United States of America
- Department of Microbiology, University of Iowa Carver College of Medicine, Iowa City, Iowa, United States of America
- * E-mail:
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10
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Ganguli K, Meng D, Rautava S, Lu L, Walker WA, Nanthakumar N. Probiotics prevent necrotizing enterocolitis by modulating enterocyte genes that regulate innate immune-mediated inflammation. Am J Physiol Gastrointest Liver Physiol 2013; 304:G132-41. [PMID: 23139215 PMCID: PMC3543644 DOI: 10.1152/ajpgi.00142.2012] [Citation(s) in RCA: 112] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/06/2012] [Accepted: 11/03/2012] [Indexed: 01/31/2023]
Abstract
Necrotizing enterocolitis (NEC), an extensive intestinal inflammatory disease of premature infants, is caused, in part, by an excessive inflammatory response to initial bacterial colonization due to the immature expression of innate immune response genes. In a randomized placebo-controlled clinical trial, supplementation of very low birth weight infants with probiotics significantly reduced the incidence of NEC. The primary goal of this study was to determine whether secreted products of these two clinically effective probiotic strains, Bifidobacterium infantis and Lactobacillus acidophilus, prevented NEC by accelerating the maturation of intestinal innate immune response genes and whether both strains are required for this effect. After exposure to probiotic conditioned media (PCM), immature human enterocytes, immature human intestinal xenografts, and primary enterocyte cultures of NEC tissue (NEC-IEC) were assayed for an IL-8 and IL-6 response to inflammatory stimuli. The latter two models were also assayed for innate immune response gene expression. In the immature xenograft, PCM exposure significantly attenuated LPS and IL-1β-induced IL-8 and IL-6 expression, decreased TLR2 mRNA and TLR4 mRNA, and increased mRNA levels of specific negative regulators of inflammation, SIGIRR and Tollip. In NEC-IEC, PCM decreased TLR2-dependent IL-8 and IL-6 induction and increased SIGIRR and Tollip expression. The attenuated inflammatory response with PCM was reversed with Tollip siRNA-mediated knockdown. The anti-inflammatory secreted factor is a 5- to 10-kDa molecule resistant to DNase, RNase, protease, heat stress, and acid exposure. B. infantis-conditioned media showed superior anti-inflammatory properties to that of L. acidophilus in immature human enterocytes, suggesting a strain specificity to this effect. We conclude that PCM promotes maturation of innate immune response gene expression, potentially explaining the protective effects of probiotics in clinical NEC.
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MESH Headings
- Animals
- Bifidobacterium/growth & development
- Bifidobacterium/metabolism
- Cells, Cultured
- Culture Media, Conditioned/metabolism
- Enterocolitis, Necrotizing/genetics
- Enterocolitis, Necrotizing/immunology
- Enterocolitis, Necrotizing/microbiology
- Enterocolitis, Necrotizing/prevention & control
- Enterocytes/immunology
- Enterocytes/microbiology
- Gene Expression Regulation
- Humans
- Immunity, Innate/genetics
- Inflammation Mediators/metabolism
- Interleukin-6/metabolism
- Interleukin-8/metabolism
- Intestine, Small/immunology
- Intestine, Small/microbiology
- Intestine, Small/transplantation
- Intracellular Signaling Peptides and Proteins/genetics
- Intracellular Signaling Peptides and Proteins/metabolism
- Lactobacillus acidophilus/growth & development
- Lactobacillus acidophilus/metabolism
- Mice
- Mice, SCID
- Organ Culture Techniques
- Primary Cell Culture
- Probiotics
- RNA Interference
- Receptors, Interleukin-1/genetics
- Receptors, Interleukin-1/metabolism
- Toll-Like Receptor 2/genetics
- Toll-Like Receptor 2/metabolism
- Toll-Like Receptor 4/genetics
- Toll-Like Receptor 4/metabolism
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Affiliation(s)
- Kriston Ganguli
- Mucosal Immunology Laboratory, Division of Pediatric Gastroenterology, Massachusetts General Hospital for Children, 114 16th St. (114-3503), Charlestown, MA 02192-4404, USA.
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11
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Singh V, Raheja G, Borthakur A, Kumar A, Gill RK, Alakkam A, Malakooti J, Dudeja PK. Lactobacillus acidophilus upregulates intestinal NHE3 expression and function. Am J Physiol Gastrointest Liver Physiol 2012; 303:G1393-401. [PMID: 23086913 PMCID: PMC3532544 DOI: 10.1152/ajpgi.00345.2012] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
A major mechanism of electroneutral NaCl absorption in the human ileum and colon involves coupling of Na(+)/H(+) and Cl(-)/HCO(3)(-) exchangers. Disturbances in these mechanisms have been implicated in diarrheal conditions. Probiotics such as Lactobacillus have been indicated to be beneficial in the management of gastrointestinal disorders, including diarrhea. However, the molecular mechanisms underlying antidiarrheal effects of probiotics have not been fully understood. We have previously demonstrated Lactobacillus acidophilus (LA) to stimulate Cl(-)/HCO3- exchange activity via an increase in the surface levels and expression of the Cl(-)/HCO3- exchanger DRA in vitro and in vivo. However, the effects of LA on NHE3, the Na(+)/H(+) exchanger involved in the coupled electroneutral NaCl absorption, are not known. Current studies were, therefore, undertaken to investigate the effects of LA on the function and expression of NHE3 and to determine the mechanisms involved. Treatment of Caco2 cells with LA or its conditioned culture supernatant (CS) for 8-24 h resulted in a significant increase in Na(+)/H(+) exchange activity, mRNA, and protein levels of NHE3. LA-CS upregulation of NHE3 function and expression was also observed in SK-CO15 cells, a human colonic adenocarcinoma cell line. Additionally, LA treatment increased NHE3 promoter activity, suggesting involvement of transcriptional mechanisms. In vivo, mice gavaged with live LA showed significant increase in NHE3 mRNA and protein expression in the ileum and colonic regions. In conclusion, LA-induced increase in NHE3 expression may contribute to the upregulation of intestinal electrolyte absorption and might underlie the potential antidiarrheal effects of probiotics.
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Affiliation(s)
- Varsha Singh
- Section of Digestive Diseases and Nutrition, Department of Medicine, University of Illinois at Chicago and Jesse Brown VA Medical Center, Chicago, Illinois
| | - Geetu Raheja
- Section of Digestive Diseases and Nutrition, Department of Medicine, University of Illinois at Chicago and Jesse Brown VA Medical Center, Chicago, Illinois
| | - Alip Borthakur
- Section of Digestive Diseases and Nutrition, Department of Medicine, University of Illinois at Chicago and Jesse Brown VA Medical Center, Chicago, Illinois
| | - Anoop Kumar
- Section of Digestive Diseases and Nutrition, Department of Medicine, University of Illinois at Chicago and Jesse Brown VA Medical Center, Chicago, Illinois
| | - Ravinder K. Gill
- Section of Digestive Diseases and Nutrition, Department of Medicine, University of Illinois at Chicago and Jesse Brown VA Medical Center, Chicago, Illinois
| | - Anas Alakkam
- Section of Digestive Diseases and Nutrition, Department of Medicine, University of Illinois at Chicago and Jesse Brown VA Medical Center, Chicago, Illinois
| | - Jaleh Malakooti
- Section of Digestive Diseases and Nutrition, Department of Medicine, University of Illinois at Chicago and Jesse Brown VA Medical Center, Chicago, Illinois
| | - Pradeep K. Dudeja
- Section of Digestive Diseases and Nutrition, Department of Medicine, University of Illinois at Chicago and Jesse Brown VA Medical Center, Chicago, Illinois
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12
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Okamoto K, Fujiya M, Nata T, Ueno N, Inaba Y, Ishikawa C, Ito T, Moriichi K, Tanabe H, Mizukami Y, Chang EB, Kohgo Y. Competence and sporulation factor derived from Bacillus subtilis improves epithelial cell injury in intestinal inflammation via immunomodulation and cytoprotection. Int J Colorectal Dis 2012; 27:1039-46. [PMID: 22297864 DOI: 10.1007/s00384-012-1416-8] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 01/20/2012] [Indexed: 02/04/2023]
Abstract
INTRODUCTION Probiotics are defined as live microorganisms that, when administered in adequate amounts, confer a health benefit on the host. These probiotic effects are considered to be displayed through the mediation of effective molecules derived from these bacteria because live bacteria as well as their conditioned media exhibit beneficial effects in many cases. However, many of the probiotic-derived molecules which mediate such benefits have so far been poorly characterized. We previously found that competence and sporulation factor (CSF) activates the Akt and p38 MAPK pathways and protects epithelial cells from oxidant stress in the mammalian intestine. The purpose of this study is to determine the CSF effect on reducing intestinal inflammation. METHODS AND RESULTS A protein array demonstrated that CSF induced the anti-inflammatory cytokine, IL-10, and decreased the release of pro-inflammatory mediators, IL-4, IL-6 and CXCL-1, induced by TNF-α in Caco2/bbe cells. CSF also induced the cytoprotective protein Hsp 27 in Caco2/bbe cells. The histological score of intestinal inflammation in 2% dextran sodium sulfate (DSS)-treated mice with the administration of 10 nM CSF was significantly lower than that of control mice. CSF also improved the survival rate of mice treated with a lethal concentration of DSS. CONCLUSION Therefore, CSF is a potentially effective treatment for intestinal inflammation.
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Affiliation(s)
- Kotaro Okamoto
- Division of Gastroenterology and Hematology/Oncology, Department of Medicine, Asahikawa Medical University, 2-1, Midorigaoka-higashi, Asahikawa, Hokkaido 078-8510, Japan
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Khokhlova EV, Smeianov VV, Efimov BA, Kafarskaia LI, Pavlova SI, Shkoporov AN. Anti-inflammatory properties of intestinal Bifidobacterium strains isolated from healthy infants. Microbiol Immunol 2012; 56:27-39. [PMID: 22040047 DOI: 10.1111/j.1348-0421.2011.00398.x] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Certain Bifidobacterium strains have been shown to inhibit inflammatory responses in intestinal epithelial cells. However, the precise mechanisms of these effects, including the chemical nature of the active compounds, remain to be elucidated. Here partial characterization of the anti-inflammatory properties of Bifidobacterium strains isolated from feces of healthy infants is reported. It was found that conditioned media (CM) of all strains studied are capable of attenuating tumor necrosis factor-α (TNF-α) and lipopolysaccharide- (LPS) induced inflammatory responses in the HT-29 cell line. In contrast, neither killed bifidobacterial cells, nor cell-free extracts showed such activities. Further investigations resulted in attribution of this activity to heat-stable, non-lipophilic compound(s) resistant to protease and nuclease treatments and of molecular weight less than 3 kDa. The anti-inflammatory effects were dose- and time-dependent and associated with inhibition of IκB phosphorylation and nuclear factor-κ light chain enhancer of activated B cells (NF-κB)-dependent promoter activation. The combined treatments of cells with CMs and either LPS or TNF-α, but not with CMs alone, resulted in upregulation of transforming growth factor-β1, IκBζ, and p21(CIP) mRNAs. Our data suggest certain species-specificities of the anti-inflammatory properties of bifidobacteria. This observation should prompt additional validation studies using larger set of strains and employing the tools of comparative genomics.
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Affiliation(s)
- Ekaterina V Khokhlova
- Department of Microbiology and Virology, Russian State Medical University, Moscow, Russia
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14
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Saksena S, Goyal S, Raheja G, Singh V, Akhtar M, Nazir TM, Alrefai WA, Gill RK, Dudeja PK. Upregulation of P-glycoprotein by probiotics in intestinal epithelial cells and in the dextran sulfate sodium model of colitis in mice. Am J Physiol Gastrointest Liver Physiol 2011; 300:G1115-23. [PMID: 21350189 PMCID: PMC3119110 DOI: 10.1152/ajpgi.00027.2011] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
P-glycoprotein (P-gp) mediates efflux of xenobiotics and bacterial toxins from the intestinal mucosa into the lumen. Dysregulation of P-gp has been implicated in inflammatory bowel disease. Certain probiotics have been shown to be effective in treating inflammatory bowel disease. However, direct effects of probiotics on P-gp are not known. Current studies examined the effects of Lactobacilli on P-gp function and expression in intestinal epithelial cells. Caco-2 monolayers and a mouse model of dextran sulfate sodium-induced colitis were utilized. P-gp activity was measured as verapamil-sensitive [(3)H]digoxin transepithelial flux. Multidrug resistant 1 (MDR1)/P-gp expression was measured by real-time quantitative PCR and immunoblotting. Culture supernatant (CS; 1:10 or 1:50, 24 h) of Lactobacillus acidophilus or Lactobacillus rhamnosus treatment of differentiated Caco-2 monolayers (21 days postplating) increased (∼3-fold) MDR1/P-gp mRNA and protein levels. L. acidophilus or L. rhamnosus CS stimulated P-gp activity (∼2-fold, P < 0.05) via phosphoinositide 3-kinase and ERK1/2 MAPK pathways. In mice, L. acidophilus or L. rhamnosus treatment (3 × 10(9) colony-forming units) increased mdr1a/P-gp mRNA and protein expression in the ileum and colon (2- to 3-fold). In the dextran sulfate sodium (DSS)-induced colitis model (3% DSS in drinking water for 7 days), the degree of colitis as judged by histological damage and myeloperoxidase activity was reduced by L. acidophilus. L. acidophilus treatment to DSS-treated mice blocked the reduced expression of mdr1a/P-gp mRNA and protein in the distal colon. These findings suggest that Lactobacilli or their soluble factors stimulate P-gp expression and function under normal and inflammatory conditions. These data provide insights into a novel mechanism involving P-gp upregulation in beneficial effects of probiotics in intestinal inflammatory disorders.
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Affiliation(s)
- Seema Saksena
- Section of Digestive Diseases and Nutrition, Department of Medicine, University of Illinois at Chicago, Jesse Brown Veterans Affairs Medical Center, 60612, USA.
| | - Sonia Goyal
- 1Section of Digestive Diseases and Nutrition, Department of Medicine, and
| | - Geetu Raheja
- 1Section of Digestive Diseases and Nutrition, Department of Medicine, and
| | - Varsha Singh
- 1Section of Digestive Diseases and Nutrition, Department of Medicine, and
| | - Maria Akhtar
- 1Section of Digestive Diseases and Nutrition, Department of Medicine, and
| | - Talat M. Nazir
- 2Department of Pathology, University of Illinois at Chicago and Jesse Brown Veterans Affairs Medical Center, Chicago, Illinois
| | - Waddah A. Alrefai
- 1Section of Digestive Diseases and Nutrition, Department of Medicine, and
| | - Ravinder K. Gill
- 1Section of Digestive Diseases and Nutrition, Department of Medicine, and
| | - Pradeep K. Dudeja
- 1Section of Digestive Diseases and Nutrition, Department of Medicine, and
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Cilieborg MS, Thymann T, Siggers R, Boye M, Bering SB, Jensen BB, Sangild PT. The incidence of necrotizing enterocolitis is increased following probiotic administration to preterm pigs. J Nutr 2011; 141:223-30. [PMID: 21178092 DOI: 10.3945/jn.110.128561] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Preterm birth and necrotizing enterocolitis (NEC) is associated with inappropriate gut colonization and immunity, which may be improved by probiotic bacteria. Using a preterm pig model of NEC, we investigated the effects of probiotics on intestinal structure, function, microbiology, and immunology in the immediate postnatal period. Just after birth, caesarean-delivered preterm pigs were inoculated with Lactobacillus paracasei, Bifidobacteria animalis, and Streptococcus thermophilus (total 2.4 × 10(10)/d) either as live (ProLive, n = 14) or gamma-irradiated dead bacteria (ProDead, n = 12) and compared with controls (n = 14). All pigs received parenteral nutrition for 2 d followed by enteral formula feeding until tissue collection on d 5. Compared with control pigs, intestinal weight was lower and NEC incidence was higher in both groups given probiotics (64-67 vs. 14%; P<0.01). Hexose absorption, brush border enzyme activities, and gut barrier function were lower in the ProDead group compared with the other groups (P < 0.05), whereas live probiotics induced higher expression of the proinflammatory cytokines IL-1α and IL-6 (P < 0.05). Probiotics minimally affected gut colonization, except that live probiotics induced a higher density of B. animalis and lower bacterial diversity in the distal intestinal mucosa and lower SCFA concentrations in the colon (P < 0.05). The detrimental effects of probiotic bacteria in this study may relate to the specific strain and dose combination and may have involved the very immature gut immune system and low NEC incidence in the control group. It remains to be determined whether similar adverse responses to probiotics occur in preterm infants.
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Affiliation(s)
- Malene S Cilieborg
- Department of Human Nutrition, Faculty of Life Sciences, University of Copenhagen, Frederiksberg C, Denmark
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Raheja G, Singh V, Ma K, Boumendjel R, Borthakur A, Gill RK, Saksena S, Alrefai WA, Ramaswamy K, Dudeja PK. Lactobacillus acidophilus stimulates the expression of SLC26A3 via a transcriptional mechanism. Am J Physiol Gastrointest Liver Physiol 2010; 298:G395-401. [PMID: 20044511 PMCID: PMC2838518 DOI: 10.1152/ajpgi.00465.2009] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Clinical efficacy of probiotics in treating various forms of diarrhea has been clearly established. However, mechanisms underlying antidiarrheal effects of probiotics are not completely defined. Diarrhea is caused either by decreased absorption or increased secretion of electrolytes and solutes in the intestine. In this regard, the electroneutral absorption of two major electrolytes, Na(+) and Cl(-), occurs mainly through the coupled operation of Na(+)/H(+) exchangers and Cl(-)/OH(-) exchangers. Previous studies from our laboratory have shown that Lactobacillus acidophilus (LA) acutely stimulated Cl(-)/OH(-) exchange activity via an increase in the surface levels of the apical anion exchanger SLC26A3 (DRA). However, whether probiotics influence SLC26A3 expression and promoter activity has not been examined. The present studies were, therefore, undertaken to investigate the long-term effects of LA on SLC26A3 expression and promoter activity. Treatment of Caco-2 cells with LA for 6-24 h resulted in a significant increase in Cl(-)/OH(-) exchange activity. DRA mRNA levels were also significantly elevated in response to LA treatment starting as early as 8 h. Additionally, the promoter activity of DRA was increased by more than twofold following 8 h LA treatment of Caco-2 cells. Similar to the in vitro studies, in vivo studies using mice gavaged with LA also showed significantly increased DRA mRNA ( approximately 4-fold) and protein expression in the colonic regions as assessed by Western blot analysis and immunofluorescence. In conclusion, increase in DRA promoter activity and expression may contribute to the upregulation of intestinal electrolyte absorption and might underlie the potential antidiarrheal effects of LA.
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Affiliation(s)
- Geetu Raheja
- Section of Digestive Diseases and Nutrition, Department of Medicine, University of Illinois at Chicago and Jesse Brown Veterans Affairs Medical Center, Chicago, Illinois
| | - Varsha Singh
- Section of Digestive Diseases and Nutrition, Department of Medicine, University of Illinois at Chicago and Jesse Brown Veterans Affairs Medical Center, Chicago, Illinois
| | - Ke Ma
- Section of Digestive Diseases and Nutrition, Department of Medicine, University of Illinois at Chicago and Jesse Brown Veterans Affairs Medical Center, Chicago, Illinois
| | - Redouane Boumendjel
- Section of Digestive Diseases and Nutrition, Department of Medicine, University of Illinois at Chicago and Jesse Brown Veterans Affairs Medical Center, Chicago, Illinois
| | - Alip Borthakur
- Section of Digestive Diseases and Nutrition, Department of Medicine, University of Illinois at Chicago and Jesse Brown Veterans Affairs Medical Center, Chicago, Illinois
| | - Ravinder K. Gill
- Section of Digestive Diseases and Nutrition, Department of Medicine, University of Illinois at Chicago and Jesse Brown Veterans Affairs Medical Center, Chicago, Illinois
| | - Seema Saksena
- Section of Digestive Diseases and Nutrition, Department of Medicine, University of Illinois at Chicago and Jesse Brown Veterans Affairs Medical Center, Chicago, Illinois
| | - Waddah A. Alrefai
- Section of Digestive Diseases and Nutrition, Department of Medicine, University of Illinois at Chicago and Jesse Brown Veterans Affairs Medical Center, Chicago, Illinois
| | - Krishnamurthy Ramaswamy
- Section of Digestive Diseases and Nutrition, Department of Medicine, University of Illinois at Chicago and Jesse Brown Veterans Affairs Medical Center, Chicago, Illinois
| | - Pradeep K. Dudeja
- Section of Digestive Diseases and Nutrition, Department of Medicine, University of Illinois at Chicago and Jesse Brown Veterans Affairs Medical Center, Chicago, Illinois
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Effect of four probiotic strains and Escherichia coli O157:H7 on tight junction integrity and cyclo-oxygenase expression. Res Microbiol 2008; 159:692-8. [PMID: 18783733 DOI: 10.1016/j.resmic.2008.08.002] [Citation(s) in RCA: 84] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2008] [Revised: 07/17/2008] [Accepted: 08/04/2008] [Indexed: 12/17/2022]
Abstract
Controversy exists as to whether contact between a probiotic bacterial cell and an epithelial cell in the gut is needed to confer beneficial effects of probiotics, or whether metabolites from probiotics are sufficient to cause this effect. To address this question, Caco-2 cells were treated with cell-free supernatants of four probiotics, Bifidobacterium lactis 420, Bifidobacterium lactis HN019, Lactobacillus acidophilus NCFM, Lactobacillus salivarius Ls-33, and by a cell-free supernatant of a pathogenic bacteria, Escherichia coli O157:H7 (EHEC). Tight junction integrity as well as expression of cyclo-oxygenases, which are prostaglandin-producing enzymes, were measured. Probiotic-specific as well as EHEC-specific effects on tight junction integrity and cyclo-oxygenase expression were evident, indicating that live bacterial cells were not necessary for the manifestation of the effects. B. lactis 420 cell-free supernatant increased tight junction integrity, while EHEC cell-free supernatant induced damage on tight junctions. In general, EHEC and probiotics had opposite effects upon cyclo-oxygenase expression. Furthermore, B. lactis 420 cell-free supernatant protected the tight junctions from EHEC-induced damage when administered prior to the cell-free supernatant of EHEC. These results indicate that probiotics produce bioactive metabolites, suggesting that consumption of specific probiotic bacteria might be beneficial in protecting intestinal epithelial cells from the deleterious effects of pathogenic bacteria.
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Antibiotic-induced perturbations of the intestinal microbiota alter host susceptibility to enteric infection. Infect Immun 2008; 76:4726-36. [PMID: 18678663 DOI: 10.1128/iai.00319-08] [Citation(s) in RCA: 361] [Impact Index Per Article: 22.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Intestinal microbiota comprises microbial communities that reside in the gastrointestinal tract and are critical to normal host physiology. Understanding the microbiota's role in host response to invading pathogens will further advance our knowledge of host-microbe interactions. Salmonella enterica serovar Typhimurium was used as a model enteric pathogen to investigate the effect of intestinal microbiota perturbation on host susceptibility to infection. Antibiotics were used to perturb the intestinal microbiota. C57BL/6 mice were treated with clinically relevant doses of streptomycin and vancomycin in drinking water for 2 days, followed by oral infection with Salmonella enterica serovar Typhimurium. Alterations in microbiota composition and numbers were evaluated by fluorescent in situ hybridization, differential plating, and Sybr green staining. Antibiotics had a dose-dependent effect on intestinal microbiota composition. The chosen antibiotic regimen did not significantly alter the total numbers of intestinal bacteria but altered the microbiota composition. Greater preinfection perturbations in the microbiota resulted in increased mouse susceptibility to Salmonella serovar Typhimurium intestinal colonization, greater postinfection alterations in the microbiota, and more severe intestinal pathology. These results suggest that antibiotic treatment alters the balance of the microbial community, which predisposes the host to Salmonella serovar Typhimurium infection, demonstrating the importance of a healthy microbiota in host response to enteric pathogens.
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Abstract
Necrotizing enterocolitis (NEC) is an inflammatory bowel disease largely affecting low birth weight, premature infants. Once acquired, NEC is accompanied by significant mortality and morbid sequelae. Our understanding of the pathophysiology of NEC continues to evolve, and the development of NEC is likely multifactorial with resultant bowel injury mediated through a final, common inflammatory pathway. The predisposition for NEC appears to involve the interplay between intestinal integrity and function, enteral feeding and bacterial colonization, and regulation of the gastrointestinal and systemic inflammatory response. Commensal organisms or probiotics have been shown to be crucial in the development and modulation of each of these factors within the intestinal epithelium. As a result, probiotic supplementation has been proposed as a promising new intervention for the prevention of NEC. To understand the potential utility of probiotics in NEC, we will discuss: the components of gut defense; the role of the intestinal ecosystem in modulating immunity and inflammation; bacterial colonization patterns in the preterm infant compared with patterns seen in the healthy, full-term infant; the evidence for probiotic use in other populations and diseases; and finally, the evidence of probiotic use specific to the preterm infant and NEC.
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Affiliation(s)
- Camilia R Martin
- Department of Pediatrics, Harvard Medical School, Beth Israel Deaconess Medical Center, Boston, MA, USA
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