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Dupont HL. Review article: evidence for the role of gut microbiota in irritable bowel syndrome and its potential influence on therapeutic targets. Aliment Pharmacol Ther 2014; 39:1033-42. [PMID: 24665829 DOI: 10.1111/apt.12728] [Citation(s) in RCA: 109] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/04/2013] [Revised: 11/18/2013] [Accepted: 03/06/2014] [Indexed: 12/12/2022]
Abstract
BACKGROUND Irritable bowel syndrome (IBS) is a prevalent gastrointestinal disease with a substantial social and economic burden. Treatment options remain limited and research on the aetiology and pathophysiology of this multifactorial disease is ongoing. AIM To discuss the potential role of gut microbiota in the pathophysiology of IBS and to identify possible interactions with pathophysiologic targets in IBS. METHODS Articles were identified via a PubMed database search ['irritable bowel syndrome' AND (anti-bacterial OR antibiotic OR flora OR microbiota OR microflora OR probiotic)]. English-language articles were screened for relevance. Full review of publications for the relevant studies was conducted, including additional publications that were identified from individual article reference lists. RESULTS The role of gut microbiota in IBS is supported by varying lines of evidence from animal and human studies. For example, post-infectious IBS in humans is well documented. In addition, certain probiotics and nonsystemic antibiotics appear to be efficacious in the treatment of IBS. Mechanisms involved in improving IBS symptoms likely go beyond mere changes in the composition of the gut microbiota, and accumulating animal data support the interplay of microbiota with other IBS targets, such as the gut-brain axis, visceral hypersensitivity, mucosal inflammation and motility. CONCLUSION The role of the gut microbiota is still being elucidated; however, it appears to be one of several important factors that contributes to the aetiology and pathophysiology of the irritable bowel syndrome.
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Affiliation(s)
- H L Dupont
- St Luke's Medical Center, and Baylor College of Medicine, The University of Texas School of Public Health, Houston, TX, USA
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IV ECO, III ECO, Johnson DA. Clinical update for the diagnosis and treatment of Clostridium difficile infection. World J Gastrointest Pharmacol Ther 2014; 5:1-26. [PMID: 24729930 PMCID: PMC3951810 DOI: 10.4292/wjgpt.v5.i1.1] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/17/2013] [Revised: 10/06/2013] [Accepted: 12/09/2013] [Indexed: 02/06/2023] Open
Abstract
Clostridium difficile infection (CDI) presents a rapidly evolving challenge in the battle against hospital-acquired infections. Recent advances in CDI diagnosis and management include rapid changes in diagnostic approach with the introduction of newer tests, such as detection of glutamate dehydrogenase in stool and polymerase chain reaction to detect the gene for toxin production, which will soon revolutionize the diagnostic approach to CDI. New medications and multiple medical society guidelines have introduced changing concepts in the definitions of severity of CDI and the choice of therapeutic agents, while rapid expansion of data on the efficacy of fecal microbiota transplantation heralds a revolutionary change in the management of patients suffering multiple relapses of CDI. Through a comprehensive review of current medical literature, this article aims to offer an intensive review of the current state of CDI diagnosis, discuss the strengths and limitations of available laboratory tests, compare both current and future treatments options and offer recommendations for best practice strategies.
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Prantera C, Scribano ML. Rifaximin and Crohn’s disease. World J Gastroenterol 2013; 19:7487-7488. [PMID: 24259983 PMCID: PMC3831234 DOI: 10.3748/wjg.v19.i42.7487] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/02/2013] [Revised: 09/02/2013] [Accepted: 09/17/2013] [Indexed: 02/06/2023] Open
Abstract
In a recent article, Longman and Swaminath analyzed our paper on the use of rifaximin in patients with moderately active Crohn’s disease (CD). Here we report some considerations concerning their article. The exploratory post-hoc subgroup analysis showed that early-stage disease and, differently from that written by Longman and Swaminath, also colonic involvement seemed to be associated with a significant higher efficacy of rifaximin-EIR 800 mg twice daily. Early-stage disease is generally considered as the more easily treatable phase of CD, and the better response to rifaximin in Crohn’s colitis is in accordance with the high concentration of bacteria in the colon. In addition, patients with C reactive protein level > 5 mg/L achieved remission more significantly than patients with normal values, thus suggesting that the symptoms were probably caused by inflammation instead of by non-inflammatory causes. We also analyze the role of rifaximin against gut bacteria and the clinical situations that could obtain the best results from antibiotics.
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Darkoh C, Brown EL, Kaplan HB, DuPont HL. Bile salt inhibition of host cell damage by Clostridium difficile toxins. PLoS One 2013; 8:e79631. [PMID: 24244530 PMCID: PMC3823588 DOI: 10.1371/journal.pone.0079631] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2013] [Accepted: 09/21/2013] [Indexed: 02/06/2023] Open
Abstract
Virulent Clostridium difficile strains produce toxin A and/or toxin B that are the etiological agents of diarrhea and pseudomembranous colitis. Treatment of C. difficile infections (CDI) has been hampered by resistance to multiple antibiotics, sporulation, emergence of strains with increased virulence, recurrence of the infection, and the lack of drugs that preserve or restore the colonic bacterial flora. As a result, there is new interest in non-antibiotic CDI treatments. The human conjugated bile salt taurocholate was previously shown in our laboratory to inhibit C. difficile toxin A and B activities in an in vitro assay. Here we demonstrate for the first time in an ex vivo assay that taurocholate can protect Caco-2 colonic epithelial cells from the damaging effects of the C. difficile toxins. Using caspase-3 and lactate dehydrogenase assays, we have demonstrated that taurocholate reduced the extent of toxin B-induced apoptosis and cell membrane damage. Confluent Caco-2 cells cultured with toxin B induced elevated caspase-3 activity. Remarkably, addition of 5 mM taurocholate reduced caspase-3 activity in cells treated with 2, 4, 6, and 12 µg/ml of toxin B by 99%, 78%, 64%, and 60%, respectively. Furthermore, spent culture medium from Caco-2 cells incubated with both toxin B and taurocholate exhibited significantly decreased lactate dehydrogenase activity compared to spent culture medium from cells incubated with toxin B only. Our results suggest that the mechanism of taurocholate-mediated inhibition functions at the level of toxin activity since taurocholate did not affect C. difficile growth and toxin production. These findings open up a new avenue for the development of non-antibiotic therapeutics for CDI treatment.
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Affiliation(s)
- Charles Darkoh
- The University of Texas School of Public Health, Division of Epidemiology, Human Genetics and Environmental Sciences, Center For Infectious Diseases, Houston, Texas, United States of America
- The University of Texas Graduate School of Biomedical Sciences, Houston, Texas, United States of America
- * E-mail:
| | - Eric L. Brown
- The University of Texas School of Public Health, Division of Epidemiology, Human Genetics and Environmental Sciences, Center For Infectious Diseases, Houston, Texas, United States of America
| | - Heidi B. Kaplan
- The University of Texas Graduate School of Biomedical Sciences, Houston, Texas, United States of America
- The University of Texas Medical School, Houston, Texas, United States of America
| | - Herbert L. DuPont
- The University of Texas School of Public Health, Division of Epidemiology, Human Genetics and Environmental Sciences, Center For Infectious Diseases, Houston, Texas, United States of America
- The University of Texas Graduate School of Biomedical Sciences, Houston, Texas, United States of America
- The University of Texas Medical School, Houston, Texas, United States of America
- St. Luke's Episcopal Hospital, Houston, Texas, United States of America
- Baylor College of Medicine, Houston, Texas, United States of America
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Schrodt C, McHugh EE, Gawinowicz MA, DuPont HL, Brown EL. Rifaximin-mediated changes to the epithelial cell proteome: 2-D gel analysis. PLoS One 2013; 8:e68550. [PMID: 23922656 PMCID: PMC3724845 DOI: 10.1371/journal.pone.0068550] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2013] [Accepted: 05/30/2013] [Indexed: 12/11/2022] Open
Abstract
Rifaximin is a semi-synthetic rifamycin derivative that is used to treat different conditions including bacterial diarrhea and hepatic encephalopathy. Rifaximin is of particular interest because it is poorly adsorbed in the intestines and has minimal effect on colonic microflora. We previously demonstrated that rifaximin affected epithelial cell physiology by altering infectivity by enteric pathogens and baseline inflammation suggesting that rifaximin conferred cytoprotection against colonization and infection. Effects of rifaximin on epithelial cells were further examined by comparing the protein expression profile of cells pretreated with rifaximin, rifampin (control antibiotic), or media (untreated). Two-dimensional (2-D) gel electrophoresis identified 36 protein spots that were up- or down-regulated by over 1.7-fold in rifaximin treated cells compared to controls. 15 of these spots were down-regulated, including annexin A5, intestinal-type alkaline phosphatase, histone H4, and histone-binding protein RbbP4. 21 spots were up-regulated, including heat shock protein (HSP) 90α and fascin. Many of the identified proteins are associated with cell structure and cytoskeleton, transcription and translation, and cellular metabolism. These data suggested that in addition to its antimicrobial properties, rifaximin may alter host cell physiology that provides cytoprotective effects against bacterial pathogens.
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Affiliation(s)
- Caroline Schrodt
- Center for Infectious Diseases, the University of Texas School of Public Health, Houston, Texas, United States of America
| | - Erin E. McHugh
- Center for Infectious Diseases, the University of Texas School of Public Health, Houston, Texas, United States of America
| | - Mary Ann Gawinowicz
- Protein Core Facility, Columbia University College, New York, New York, United States of America
| | - Herbert L. DuPont
- Center for Infectious Diseases, the University of Texas School of Public Health, Houston, Texas, United States of America
- Internal Medicine Services, St. Luke’s Episcopal Hospital and Department of Medicine, Infectious Diseases Section, Baylor College of Medicine, Houston, Texas, United States of America
| | - Eric L. Brown
- Center for Infectious Diseases, the University of Texas School of Public Health, Houston, Texas, United States of America
- * E-mail:
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Modulation of the fecal bile acid profile by gut microbiota in cirrhosis. J Hepatol 2013; 58:949-55. [PMID: 23333527 PMCID: PMC3936319 DOI: 10.1016/j.jhep.2013.01.003] [Citation(s) in RCA: 567] [Impact Index Per Article: 51.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/25/2012] [Revised: 11/01/2012] [Accepted: 01/03/2013] [Indexed: 02/07/2023]
Abstract
BACKGROUND & AIMS The 7α-dehydroxylation of primary bile acids (BAs), chenodeoxycholic (CDCA) and cholic acid (CA) into the secondary BAs, lithocholic (LCA) and deoxycholic acid (DCA), is a key function of the gut microbiota. We aimed at studying the linkage between fecal BAs and gut microbiota in cirrhosis since this could help understand cirrhosis progression. METHODS Fecal microbiota were analyzed by culture-independent multitagged-pyrosequencing, fecal BAs using HPLC and serum BAs using LC-MS in controls, early (Child A) and advanced cirrhotics (Child B/C). A subgroup of early cirrhotics underwent BA and microbiota analysis before/after eight weeks of rifaximin. RESULTS Cross-sectional: 47 cirrhotics (24 advanced) and 14 controls were included. In feces, advanced cirrhotics had the lowest total, secondary, secondary/primary BA ratios, and the highest primary BAs compared to early cirrhotics and controls. Secondary fecal BAs were detectable in all controls but in a significantly lower proportion of cirrhotics (p<0.002). Serum primary BAs were higher in advanced cirrhotics compared to the rest. Cirrhotics, compared to controls, had a higher Enterobacteriaceae (potentially pathogenic) but lower Lachonospiraceae, Ruminococcaceae and Blautia (7α-dehydroxylating bacteria) abundance. CDCA was positively correlated with Enterobacteriaceae (r=0.57, p<0.008) while Ruminococcaceae were positively correlated with DCA (r=0.4, p<0.05). A positive correlation between Ruminococcaceae and DCA/CA (r=0.82, p<0.012) and Blautia with LCA/CDCA (r=0.61, p<0.03) was also seen. Prospective study: post-rifaximin, six early cirrhotics had reduction in Veillonellaceae and in secondary/primary BA ratios. CONCLUSIONS Cirrhosis, especially advanced disease, is associated with a decreased conversion of primary to secondary fecal BAs, which is linked to abundance of key gut microbiome taxa.
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Bajaj JS, Heuman DM, Sanyal AJ, Hylemon PB, Sterling RK, Stravitz RT, Fuchs M, Ridlon JM, Daita K, Monteith P, Noble NA, White MB, Fisher A, Sikaroodi M, Rangwala H, Gillevet PM. Modulation of the metabiome by rifaximin in patients with cirrhosis and minimal hepatic encephalopathy. PLoS One 2013; 8:e60042. [PMID: 23565181 PMCID: PMC3615021 DOI: 10.1371/journal.pone.0060042] [Citation(s) in RCA: 314] [Impact Index Per Article: 28.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2012] [Accepted: 02/19/2013] [Indexed: 12/12/2022] Open
Abstract
UNLABELLED Hepatic encephalopathy (HE) represents a dysfunctional gut-liver-brain axis in cirrhosis which can negatively impact outcomes. This altered gut-brain relationship has been treated using gut-selective antibiotics such as rifaximin, that improve cognitive function in HE, especially its subclinical form, minimal HE (MHE). However, the precise mechanism of the action of rifaximin in MHE is unclear. We hypothesized that modulation of gut microbiota and their end-products by rifaximin would affect the gut-brain axis and improve cognitive performance in cirrhosis. Aim To perform a systems biology analysis of the microbiome, metabolome and cognitive change after rifaximin in MHE. METHODS Twenty cirrhotics with MHE underwent cognitive testing, endotoxin analysis, urine/serum metabolomics (GC and LC-MS) and fecal microbiome assessment (multi-tagged pyrosequencing) at baseline and 8 weeks post-rifaximin 550 mg BID. Changes in cognition, endotoxin, serum/urine metabolites (and microbiome were analyzed using recommended systems biology techniques. Specifically, correlation networks between microbiota and metabolome were analyzed before and after rifaximin. RESULTS There was a significant improvement in cognition(six of seven tests improved, p<0.01) and endotoxemia (0.55 to 0.48 Eu/ml, p = 0.02) after rifaximin. There was a significant increase in serum saturated (myristic, caprylic, palmitic, palmitoleic, oleic and eicosanoic) and unsaturated (linoleic, linolenic, gamma-linolenic and arachnidonic) fatty acids post-rifaximin. No significant microbial change apart from a modest decrease in Veillonellaceae and increase in Eubacteriaceae was observed. Rifaximin resulted in a significant reduction in network connectivity and clustering on the correlation networks. The networks centered on Enterobacteriaceae, Porphyromonadaceae and Bacteroidaceae indicated a shift from pathogenic to beneficial metabolite linkages and better cognition while those centered on autochthonous taxa remained similar. CONCLUSIONS Rifaximin is associated with improved cognitive function and endotoxemia in MHE, which is accompanied by alteration of gut bacterial linkages with metabolites without significant change in microbial abundance. TRIAL REGISTRATION ClinicalTrials.gov NCT01069133.
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Affiliation(s)
- Jasmohan S Bajaj
- Division of Gastroenterology, Hepatology and Nutrition, Virginia Commonwealth University and McGuire Veterans Affairs Medical Center, Richmond, Virginia, United States of America.
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Nikolova B, Kostadinova A, Dimitrov B, Zhelev Z, Bakalova R, Aoki I, Saga T, Tsoneva I. Fluorescent imaging for assessment of the effect of combined application of electroporation and rifampicin on HaCaT cells as a new therapeutic approach for psoriasis. SENSORS 2013; 13:3625-34. [PMID: 23493125 PMCID: PMC3658765 DOI: 10.3390/s130303625] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/11/2013] [Revised: 02/13/2013] [Accepted: 03/06/2013] [Indexed: 11/26/2022]
Abstract
The study aimed to clarify the role of electric pulses in combination with chemotherapy on the viability of keratinocyte cell line HaCaT, in the context of its application as a new therapeutic approach for psoriasis. The data show that electroporation of HaCaT cells in combination with rifampicin induces cytoskeleton disruption and increases permeability of cell monolayer due to cell-cell junctions' interruption, visualized by fluorescent imaging of E-cadherin and actin integrity. This was accompanied with synergistic reduction of cell viability. The study proposes a new opportunity for more effective skin treatment than chemotherapy. The future application of this electrochemotherapeutic approach for combined local treatment of psoriasis may have serous benefits because of a high possibility to avoid side-effects of conventional chemotherapy.
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Affiliation(s)
- Biliana Nikolova
- Institute of Biophysics and Biomedical Engineering, Bulgarian Academy of Sciences, Acad.G. Bonchev Str., bl. 21, Sofia 1113, Bulgaria; E-Mails: (B.N.); (A.K.); (B.D.); (Z.Z.); (I.T.)
| | - Anelia Kostadinova
- Institute of Biophysics and Biomedical Engineering, Bulgarian Academy of Sciences, Acad.G. Bonchev Str., bl. 21, Sofia 1113, Bulgaria; E-Mails: (B.N.); (A.K.); (B.D.); (Z.Z.); (I.T.)
| | - Borislav Dimitrov
- Institute of Biophysics and Biomedical Engineering, Bulgarian Academy of Sciences, Acad.G. Bonchev Str., bl. 21, Sofia 1113, Bulgaria; E-Mails: (B.N.); (A.K.); (B.D.); (Z.Z.); (I.T.)
| | - Zhivko Zhelev
- Institute of Biophysics and Biomedical Engineering, Bulgarian Academy of Sciences, Acad.G. Bonchev Str., bl. 21, Sofia 1113, Bulgaria; E-Mails: (B.N.); (A.K.); (B.D.); (Z.Z.); (I.T.)
- Medical Faculty, Trakia University, 11 Armeiska Str., Stara Zagora 6000, Bulgaria
| | - Rumiana Bakalova
- Molecular Imaging Center, National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage-ku, Chiba 263-8555, Japan; E-Mails: (I.A.); (T.S.)
- Medical Faculty, Sofia University, 1 Koziak Str., Sofia 1407, Bulgaria
- Author to whom correspondence should be addressed; E-Mail: ; Tel.: +81-42-206-3274; Fax: +81-42-206-9470
| | - Ichio Aoki
- Molecular Imaging Center, National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage-ku, Chiba 263-8555, Japan; E-Mails: (I.A.); (T.S.)
| | - Tsuneo Saga
- Molecular Imaging Center, National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage-ku, Chiba 263-8555, Japan; E-Mails: (I.A.); (T.S.)
| | - Iana Tsoneva
- Institute of Biophysics and Biomedical Engineering, Bulgarian Academy of Sciences, Acad.G. Bonchev Str., bl. 21, Sofia 1113, Bulgaria; E-Mails: (B.N.); (A.K.); (B.D.); (Z.Z.); (I.T.)
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Koo HL, Sabounchi S, Huang DB, DuPont HL. Rifaximin therapy of irritable bowel syndrome. CLINICAL MEDICINE INSIGHTS. GASTROENTEROLOGY 2012; 5:31-41. [PMID: 24833932 PMCID: PMC3987760 DOI: 10.4137/cgast.s7382] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Irritable bowel syndrome (IBS) is a common gastrointestinal disorder characterized by abdominal pain and altered bowel habits in the absence of specific organic pathology. Although the underlying pathogenesis of IBS is not well-understood, small intestinal bacterial overgrowth (SIBO) or other abnormalities in the gut flora is believed to contribute to the development of a subset of IBS cases. Rifaximin is a poorly absorbed antimicrobial with activity against enteric pathogens. A number of studies have shown a significant improvement in IBS symptoms with antibiotic therapy including rifaximin. In this review, we discuss the pharmacokinetics, in vitro susceptibility profile, and efficacy and safety data from clinical trials of rifaximin treatment of IBS.
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Affiliation(s)
- Hoonmo L Koo
- Baylor College of Medicine, Houston, TX. ; University of Texas at Houston School of Public Health, Houston, TX
| | | | | | - Herbert L DuPont
- Baylor College of Medicine, Houston, TX. ; University of Texas at Houston School of Public Health, Houston, TX. ; St. Luke's Episcopal Hospital
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Bielaszewska M, Idelevich EA, Zhang W, Bauwens A, Schaumburg F, Mellmann A, Peters G, Karch H. Effects of antibiotics on Shiga toxin 2 production and bacteriophage induction by epidemic Escherichia coli O104:H4 strain. Antimicrob Agents Chemother 2012; 56:3277-82. [PMID: 22391549 PMCID: PMC3370775 DOI: 10.1128/aac.06315-11] [Citation(s) in RCA: 145] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
The role of antibiotics in treatment of enterohemorrhagic Escherichia coli (EHEC) infections is controversial because of concerns about triggering hemolytic-uremic syndrome (HUS) by increasing Shiga toxin (Stx) production. During the recent large EHEC O104:H4 outbreak, antibiotic therapy was indicated for some patients. We tested a diverse panel of antibiotics to which the outbreak strain is susceptible to interrogate the effects of subinhibitory antibiotic concentrations on induction of stx(2)-harboring bacteriophages, stx(2) transcription, and Stx2 production in this emerging pathogen. Ciprofloxacin significantly increased stx(2)-harboring phage induction and Stx2 production in outbreak isolates (P values of <0.001 to <0.05), while fosfomycin, gentamicin, and kanamycin insignificantly influenced them (P > 0.1) and chloramphenicol, meropenem, azithromycin, rifaximin, and tigecycline significantly decreased them (P ≤ 0.05). Ciprofloxacin and chloramphenicol significantly upregulated and downregulated stx(2) transcription, respectively (P < 0.01); the other antibiotics had insignificant effects (P > 0.1). Meropenem, azithromycin, and rifaximin, which were used for necessary therapeutic or prophylactic interventions during the EHEC O104:H4 outbreak, as well as tigecycline, neither induced stx(2)-harboring phages nor increased stx(2) transcription or Stx2 production in the outbreak strain. These antibiotics might represent therapeutic options for patients with EHEC O104:H4 infection if antibiotic treatment is inevitable. We await further analysis of the epidemic to determine if usage of these agents was associated with an altered risk of developing HUS.
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Affiliation(s)
- Martina Bielaszewska
- Institute of Hygiene and the National Consulting Laboratory for Hemolytic Uremic Syndrome, University of Münster, Münster, Germany
| | | | - Wenlan Zhang
- Institute of Hygiene and the National Consulting Laboratory for Hemolytic Uremic Syndrome, University of Münster, Münster, Germany
| | - Andreas Bauwens
- Institute of Hygiene and the National Consulting Laboratory for Hemolytic Uremic Syndrome, University of Münster, Münster, Germany
| | - Frieder Schaumburg
- Institute of Medical Microbiology, University of Münster, Münster, Germany
| | - Alexander Mellmann
- Institute of Hygiene and the National Consulting Laboratory for Hemolytic Uremic Syndrome, University of Münster, Münster, Germany
- Interdisciplinary Center of Clinical Research (IZKF), University of Münster, Münster, Germany
| | - Georg Peters
- Institute of Medical Microbiology, University of Münster, Münster, Germany
- Interdisciplinary Center of Clinical Research (IZKF), University of Münster, Münster, Germany
| | - Helge Karch
- Institute of Hygiene and the National Consulting Laboratory for Hemolytic Uremic Syndrome, University of Münster, Münster, Germany
- Interdisciplinary Center of Clinical Research (IZKF), University of Münster, Münster, Germany
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Lv XB, Lian GY, Wang HR, Song E, Yao H, Wang MH. Renal function at hospital admission and mortality due to acute kidney injury after myocardial infarction. PLoS One 2012. [PMID: 23717443 DOI: 10.1371/journal.pone] [Citation(s) in RCA: 487] [Impact Index Per Article: 40.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND The role of an impaired estimated glomerular filtration rate (eGFR) at hospital admission in the outcome of acute kidney injury (AKI) after acute myocardial infarction (AMI) has been underreported. The aim of this study was to assess the influence of an admission eGFR<60 mL/min/1.73 m(2) on the incidence and early and late mortality of AMI-associated AKI. METHODS A prospective study of 828 AMI patients was performed. AKI was defined as a serum creatinine increase of ≥ 50% from the time of admission (RIFLE criteria) in the first 7 days of hospitalization. Patients were divided into subgroups according to their eGFR upon hospital admission (MDRD formula, mL/min/1.73 m(2)) and the development of AKI: eGFR ≥ 60 without AKI, eGFR<60 without AKI, eGFR ≥ 60 with AKI and eGFR<60 with AKI. RESULTS Overall, 14.6% of the patients in this study developed AKI. The admission eGFR had no impact on the incidence of AKI. However, the admission eGFR was associated with the outcome of AMI-associated AKI. The adjusted hazard ratios (AHR, Cox multivariate analysis) for 30-day mortality were 2.00 (95% CI 1.11-3.61) for eGFR<60 without AKI, 4.76 (95% CI 2.45-9.26) for eGFR ≥ 60 with AKI and 6.27 (95% CI 3.20-12.29) for eGFR<60 with AKI. Only an admission eGFR of <60 with AKI was significantly associated with a 30-day to 1-year mortality hazard (AHR 3.05, 95% CI 1.50-6.19). CONCLUSIONS AKI development was associated with an increased early mortality hazard in AMI patients with either preserved or impaired admission eGFR. Only the association of impaired admission eGFR and AKI was associated with an increased hazard for late mortality among these patients.
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Affiliation(s)
- Xiao-Bin Lv
- Medical Research Center Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou 510120, China
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Intestinal decontamination inhibits TLR4 dependent fibronectin-mediated cross-talk between stellate cells and endothelial cells in liver fibrosis in mice. J Hepatol 2012; 56:893-9. [PMID: 22173161 PMCID: PMC3307873 DOI: 10.1016/j.jhep.2011.11.013] [Citation(s) in RCA: 105] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/21/2011] [Revised: 10/26/2011] [Accepted: 11/03/2011] [Indexed: 02/07/2023]
Abstract
BACKGROUND & AIMS Liver fibrosis is associated with angiogenesis and leads to portal hypertension. Certain antibiotics reduce complications of liver failure in humans, however, the effects of antibiotics on the pathologic alterations of the disease are not fully understood. The aim of this study was to test whether the non-absorbable antibiotic rifaximin could attenuate fibrosis progression and portal hypertension in vivo, and explore potential mechanisms in vitro. METHODS The effect of rifaximin on portal pressure, fibrosis, and angiogenesis was examined in wild type and Toll-like receptor 4 (TLR4) mutant mice after bile duct ligation (BDL). In vitro studies were carried out to evaluate the effect of the bacterial product and TLR agonist lipopolysaccharide (LPS) on paracrine interactions between hepatic stellate cells (HSC) and liver endothelial cells (LEC) that lead to fibrosis and portal hypertension. RESULTS Portal pressure, fibrosis, and angiogenesis were significantly lower in BDL mice receiving rifaximin compared to BDL mice receiving vehicle. Studies in TLR4 mutant mice confirmed that the effect of rifaximin was dependent on LPS/TLR4 pathway. Fibronectin (FN) was increased in the BDL liver and was reduced by rifaximin administration and thus, was explored further in vitro as a potential mediator of paracrine interactions of HSC and LEC. In vitro, LPS promoted FN production from HSC. Furthermore, HSC-derived FN promoted LEC migration and angiogenesis. CONCLUSIONS These studies expand our understanding of the relationship of intestinal microbiota with fibrosis development by identifying FN as a TLR4 dependent mediator of the matrix and vascular changes that characterize cirrhosis.
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Prantera C, Lochs H, Grimaldi M, Danese S, Scribano ML, Gionchetti P. Rifaximin-extended intestinal release induces remission in patients with moderately active Crohn's disease. Gastroenterology 2012; 142:473-481.e4. [PMID: 22155172 DOI: 10.1053/j.gastro.2011.11.032] [Citation(s) in RCA: 128] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/13/2011] [Revised: 10/28/2011] [Accepted: 11/19/2011] [Indexed: 12/13/2022]
Abstract
BACKGROUND & AIMS Bacteria might be involved in the development and persistence of inflammation in patients with Crohn's disease (CD), and antibiotics could be used in therapy. We performed a clinical phase 2 trial to determine whether a gastroresistant formulation of rifaximin (extended intestinal release [EIR]) induced remission in patients with moderately active CD. METHODS We performed a multicenter, randomized, double-blind trial of the efficacy and safety of 400, 800, and 1200 mg rifaximin-EIR, given twice daily to 402 patients with moderately active CD for 12 weeks. Data from patients given rifaximin-EIR were compared with those from individuals given placebo, and collected during a 12-week follow-up period. The primary end point was remission (Crohn's Disease Activity Index <150) at the end of the treatment period. RESULTS At the end of the 12-week treatment period, 62% of patients who received the 800-mg dosage of rifaximin-EIR (61 of 98) were in remission, compared with 43% of patients who received placebo (43 of 101) (P = .005). A difference was maintained throughout the 12-week follow-up period (45% [40 of 89] vs 29% [28 of 98]; P = .02). Remission was achieved by 54% (56 of 104) and 47% (47 of 99) of the patients given the 400-mg and 1200-mg dosages of rifaximin-EIR, respectively; these rates did not differ from those of placebo. Patients given the 400-mg and 800-mg dosages of rifaximin-EIR had low rates of withdrawal from the study because of adverse events; rates were significantly higher among patients given the 1200-mg dosage (16% [16 of 99]). CONCLUSIONS Administration of 800 mg rifaximin-EIR twice daily for 12 weeks induced remission with few adverse events in patients with moderately active CD.
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Affiliation(s)
- Cosimo Prantera
- Gastroenterology Unit, San Camillo Forlanini Hospital, Rome, Italy.
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Garey KW, Ghantoji SS, Shah DN, Habib M, Arora V, Jiang ZD, DuPont HL. A randomized, double-blind, placebo-controlled pilot study to assess the ability of rifaximin to prevent recurrent diarrhoea in patients with Clostridium difficile infection. J Antimicrob Chemother 2011; 66:2850-5. [DOI: 10.1093/jac/dkr377] [Citation(s) in RCA: 135] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
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Abstract
Mucosal surfaces of the gut are colonized by large numbers of heterogeneous bacteria that contribute to intestinal health and disease. In genetically susceptible individuals, a 'pathogenic community' may arise, whereby abnormal gut flora contributes to alterations in the mucosa and local immune system leading to gastrointestinal disease. These diseases include enteric infections, such as Clostridium difficile infection, small intestinal bacterial overgrowth, functional gastrointestinal disorders (including IBS), IBD and colorectal cancer. Prebiotics, probiotics and synbiotics (a combination of prebiotics and probiotics) have the capacity to reverse pathologic changes in gut flora and local immunity. Intestinal health and disease need to be thoroughly characterized to understand the interplay between the indigenous microbiota, the immune system and genetic host factors. This Review provides a broad overview of the importance of the intestinal microbiota in chronic disorders of the gut.
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Abstract
INTRODUCTION Rifaximin is increasingly being used to treat acute and chronic gastrointestinal infections and disorders. The drug exerts its beneficial effect through a variety of gut-selective mechanisms involving the host intestinal microbiota. AREAS COVERED Abstracts of all publications listed in PubMed on the topic of rifaximin are reviewed to determine their potential value in the understanding of mechanisms of rifaximin activity. The author's extensive file on the drug is also used in the review. EXPERT OPINION Rifaximin inhibits a broad spectrum of bacteria in the bile-rich small bowel and susceptible bacteria in the aqueous colon, and alters microbial virulence and epithelial cell function. The different mechanisms of action of rifaximin potentially explain the use of the drug in widely varied diseases and syndromes.
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Affiliation(s)
- Herbert L DuPont
- The University of Texas School of Public Health, Baylor College of Medicine, St. Luke's Episcopal Hospital, Kelsey Research Foundation, 1200 Herman Pressler, Houston, TX 77030, USA.
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Abstract
Aerobic vaginitis (AV) is an alteration in vaginal bacterial flora that differs from bacterial vaginosis (BV). AV is characterised by an abnormal vaginal microflora accompanied by an increased localised inflammatory reaction and immune response, as opposed to the suppressed immune response that is characteristic of BV. Given the increased local production of interleukin (IL)-1, IL-6 and IL-8 associated with AV during pregnancy, not surprisingly AV is associated with an increased risk of preterm delivery, chorioamnionitis and funisitis of the fetus. There is no consensus on the optimal treatment for AV in pregnant or non-pregnant women, but a broader spectrum drug such as clindamycin is preferred above metronidazole to prevent infection-related preterm birth. The exact role of AV in pregnancy, the potential benefit of screening, and the use of newer local antibiotics, disinfectants, probiotics and immune modulators need further study.
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Affiliation(s)
- Ggg Donders
- Department of Obstetrics and Gynaecology, The Regional Hospital Heilig Hart Tienen and University Hospital Gasthuisberg Leuven, Belgium
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Maccaferri S, Vitali B, Klinder A, Brigidi P, Costabile A. Rifaximin modulates the colonic microbiota of patients with Crohn's disease: an in vitro approach using a continuous culture colonic model system--authors' response. J Antimicrob Chemother 2011. [DOI: 10.1093/jac/dkr080] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Smani Y, Domínguez-Herrera J, Pachón J. Rifampin Protects Human Lung Epithelial Cells Against Cytotoxicity Induced by Clinical Multi and Pandrug-resistant Acinetobacter baumannii. J Infect Dis 2011; 203:1110-9. [DOI: 10.1093/infdis/jiq159] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Abstract
Hepatic encephalopathy (HE) is a complication of cirrhosis, the severity of which can range from subtle, neurocognitive dysfunction (minimal HE) to more apparent and severe cognitive and motor manifestations with increasing grades of the condition (overt HE). Current treatment options are targeted at reducing the levels of ammonia and other gut-derived toxins, the purported culprits behind the pathogenesis of HE. One of these therapeutic options, the nonsystemic antibiotic rifaximin, is efficacious for the treatment of minimal and overt HE. However, HE may be a cyclic condition in which patients with overt HE enter remission following treatment and then relapse. Thus, safe, effective and well-tolerated treatments are needed to maintain HE remission. Rifaximin maintained HE remission more effectively than placebo in a large, randomized controlled trial. Rifaximin is safe and well-tolerated for the treatment of minimal and overt HE and for the maintenance of HE remission.
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Affiliation(s)
- Kevin Mullen
- Division of Gastroenterology, MetroHealth Medical Center, Case Western Reserve University, 2500 MetroHealth Drive, Cleveland, OH 44109, USA
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Maccaferri S, Vitali B, Klinder A, Kolida S, Ndagijimana M, Laghi L, Calanni F, Brigidi P, Gibson GR, Costabile A. Rifaximin modulates the colonic microbiota of patients with Crohn's disease: an in vitro approach using a continuous culture colonic model system. J Antimicrob Chemother 2010; 65:2556-65. [PMID: 20852272 DOI: 10.1093/jac/dkq345] [Citation(s) in RCA: 129] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
OBJECTIVES Rifaximin, a rifamycin derivative, has been reported to induce clinical remission of active Crohn's disease (CD), a chronic inflammatory bowel disorder. In order to understand how rifaximin affects the colonic microbiota and its metabolism, an in vitro human colonic model system was used in this study. METHODS We investigated the impact of the administration of 1800 mg/day of rifaximin on the faecal microbiota of four patients affected by colonic active CD [Crohn's disease activity index (CDAI > 200)] using a continuous culture colonic model system. We studied the effect of rifaximin on the human gut microbiota using fluorescence in situ hybridization, quantitative PCR and PCR-denaturing gradient gel electrophoresis. Furthermore, we investigated the effect of the antibiotic on microbial metabolic profiles, using (1)H-NMR and solid phase microextraction coupled with gas chromatography/mass spectrometry, and its potential genotoxicity and cytotoxicity, using Comet and growth curve assays. RESULTS Rifaximin did not affect the overall composition of the gut microbiota, whereas it caused an increase in concentration of Bifidobacterium, Atopobium and Faecalibacterium prausnitzii. A shift in microbial metabolism was observed, as shown by increases in short-chain fatty acids, propanol, decanol, nonanone and aromatic organic compounds, and decreases in ethanol, methanol and glutamate. No genotoxicity or cytotoxicity was attributed to rifaximin, and conversely rifaximin was shown to have a chemopreventive role by protecting against hydrogen peroxide-induced DNA damage. CONCLUSIONS We demonstrated that rifaximin, while not altering the overall structure of the human colonic microbiota, increased bifidobacteria and led to variation of metabolic profiles associated with potential beneficial effects on the host.
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Affiliation(s)
- Simone Maccaferri
- Department of Pharmaceutical Sciences, University of Bologna, Bologna, Italy
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