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Wang X, Zhao G, Shao S, Yao Y. Helicobacter pylori triggers inflammation and oncogenic transformation by perturbing the immune microenvironment. Biochim Biophys Acta Rev Cancer 2024; 1879:189139. [PMID: 38897421 DOI: 10.1016/j.bbcan.2024.189139] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2024] [Revised: 06/09/2024] [Accepted: 06/14/2024] [Indexed: 06/21/2024]
Abstract
The immune microenvironment plays a critical regulatory role in the pathogenesis of Helicobacter pylori (H. pylori). Understanding the mechanisms that drive the transition from chronic inflammation to cancer may provide new insights for early detection of gastric cancer. Although chronic inflammation is frequent in precancerous gastric conditions, the monitoring function of the inflammatory microenvironment in the progression from H. pylori-induced chronic inflammation to gastric cancer remains unclear. This literature review summarizes significant findings on how H. pylori triggers inflammatory responses and facilitates cancer development through the immune microenvironment. Furthermore, the implications for future research and clinical applications are also addressed. The review is divided into four main sections: inflammatory response and immune evasion mechanisms induced by H. pylori, immune dysregulation associated with gastric cancer, therapeutic implications, and future perspectives on H. pylori-induced gastric carcinogenesis with a focus on the immune microenvironment.
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Affiliation(s)
- Xiuping Wang
- Department of Clinical Laboratory, Affiliated Kunshan Hospital of Jiangsu University, Kunshan 215300, Jiangsu, China
| | - Guang Zhao
- Department of Clinical Laboratory, Affiliated Kunshan Hospital of Jiangsu University, Kunshan 215300, Jiangsu, China; Department of Emergency Medicine, Kunshan Hospital Affiliated to Jiangsu University, Kunshan 215300, Jiangsu, China
| | - Shihe Shao
- School of Medicine, Jiangsu University, Zhenjiang 212013, Jiangsu, China.
| | - Yongliang Yao
- Department of Clinical Laboratory, Affiliated Kunshan Hospital of Jiangsu University, Kunshan 215300, Jiangsu, China.
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2
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Shirani M, Shariati S, Bazdar M, Sojoudi Ghamnak F, Moradi M, Shams Khozani R, Taki E, Arabsorkhi Z, Heidary M, Eskandari DB. The immunopathogenesis of Helicobacter pylori-induced gastric cancer: a narrative review. Front Microbiol 2024; 15:1395403. [PMID: 39035439 PMCID: PMC11258019 DOI: 10.3389/fmicb.2024.1395403] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2024] [Accepted: 05/06/2024] [Indexed: 07/23/2024] Open
Abstract
Helicobacter pylori infection is a well-established risk factor for the development of gastric cancer (GC). Understanding the immunopathogenesis underlying this association is crucial for developing effective preventive and therapeutic strategies. This narrative review comprehensively explores the immunopathogenesis of H. pylori-induced GC by delving into several key aspects, emphasizing the pivotal roles played by H. pylori virulence factors, including cytotoxin-associated gene A (cagA) and vacuolating cytotoxin A (vacA), blood group antigen-binding adhesin (babA), and sialic acid binding adhesin (sabA). Moreover, the review focuses on the role of toll-like receptors (TLRs) and cytokines in the complex interplay between chronic infection and gastric carcinogenesis. Finally, the study examines the association between H. pylori evasion of the innate and adaptive immune response and development of GC. A comprehensive understanding of the immunopathogenesis of H. pylori-induced GC is essential for designing targeted interventions to prevent and manage this disease. Further research is warranted to elucidate the intricate immune responses involved and identify potential therapeutic targets to improve patient outcomes.
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Affiliation(s)
- Maryam Shirani
- Toxicology Research Center, Medical Basic Sciences Research Institute, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
| | - Saeedeh Shariati
- Toxicology Research Center, Medical Basic Sciences Research Institute, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
- Student Research Committee, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
| | - Monireh Bazdar
- School of Medicine, Razi Hospital, Ilam University of Medical Sciences, Ilam, Iran
| | | | - Melika Moradi
- Department of Microbiology, Faculty of Medicine, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
| | | | - Elahe Taki
- Department of Microbiology, School of Medicine, Kermanshah University of Medical Sciences, Kermanshah, Iran
| | - Zahra Arabsorkhi
- Department of Medical Genetics, National Institute of Genetic Engineering and Biotechnology, Tehran, Iran
| | - Mohsen Heidary
- Department of Laboratory Sciences, School of Paramedical Sciences, Sabzevar University of Medical Sciences, Sabzevar, Iran
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3
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Yang H, Wang L, Zhang M, Hu B. The Role of Adhesion in Helicobacter pylori Persistent Colonization. Curr Microbiol 2023; 80:185. [PMID: 37071212 DOI: 10.1007/s00284-023-03264-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2022] [Accepted: 03/10/2023] [Indexed: 04/19/2023]
Abstract
Helicobacter pylori (H. pylori) has coevolved with its human host for more than 100 000 years. It can safely colonize around the epithelium of gastric glands via their specific microstructures and proteins. Unless patients receive eradication treatment, H. pylori infection is always lifelong. However, few studies have discussed the reasons. This review will focus on the adhesion of H. pylori from the oral cavity to gastric mucosa and summarize the possible binding and translocation characteristics. Adhesion is the first step for persistent colonization after the directional motility, and factors related to adhesion are necessary. Outer membrane proteins, such as the blood group antigen binding adhesin (BabA) and the sialic acid binding adhesin (SabA), play pivotal roles in binding to human mucins and cellular surfaces. And this may offer different perspectives on eradication.
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Affiliation(s)
- Hang Yang
- Department of Gastroenterology, West China Hospital, Sichuan University, No.37, Guo Xue Alley, Wu Hou District, Chengdu City, 610041, Sichuan Province, China
| | - Lixia Wang
- The Second Department of Gastroenterology, The First Affiliated Hospital of Dalian Medical University, Dalian, Liaoning, China
| | - Miao Zhang
- Department of Gastroenterology, West China Hospital, Sichuan University, No.37, Guo Xue Alley, Wu Hou District, Chengdu City, 610041, Sichuan Province, China
| | - Bing Hu
- Department of Gastroenterology, West China Hospital, Sichuan University, No.37, Guo Xue Alley, Wu Hou District, Chengdu City, 610041, Sichuan Province, China.
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Luo Q, Liu N, Pu S, Zhuang Z, Gong H, Zhang D. A review on the research progress on non-pharmacological therapy of Helicobacter pylori. Front Microbiol 2023; 14:1134254. [PMID: 37007498 PMCID: PMC10063898 DOI: 10.3389/fmicb.2023.1134254] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2022] [Accepted: 03/03/2023] [Indexed: 03/19/2023] Open
Abstract
Helicobacter pylori is a pathogenic microorganism that mainly resides in the human stomach and is the major cause of chronic gastritis, peptic ulcer and gastric cancer. Up to now, the treatment of Helicobacter pylori has been predominantly based on a combination of antibiotics and proton pump inhibitors. However, the increasing antibiotic resistance greatly limits the efficacy of anti-Helicobacter pylori treatment. Turning to non-antibiotic or non-pharmacological treatment is expected to solve this problem and may become a new strategy for treating Helicobacter pylori. In this review, we outline Helicobacter pylori's colonization and virulence mechanisms. Moreover, a series of non-pharmacological treatment methods for Helicobacter pylori and their mechanisms are carefully summarized, including probiotics, oxygen-rich environment or hyperbaric oxygen therapy, antibacterial photodynamic therapy, nanomaterials, antimicrobial peptide therapy, phage therapy and modified lysins. Finally, we provide a comprehensive overview of the challenges and perspectives in developing new medical technologies for treating Helicobacter pylori without drugs.
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Affiliation(s)
- Qian Luo
- Department of Gastroenterology, The Second Clinical Medical College of Lanzhou University, LanZhou University Second Hospital, Lanzhou, China
| | - Na Liu
- Department of Gastroenterology, The Second Clinical Medical College of Lanzhou University, LanZhou University Second Hospital, Lanzhou, China
| | - Sugui Pu
- Department of Gastroenterology, The Second Clinical Medical College of Lanzhou University, LanZhou University Second Hospital, Lanzhou, China
| | - Ze Zhuang
- Department of Gastroenterology, The Second Clinical Medical College of Lanzhou University, LanZhou University Second Hospital, Lanzhou, China
| | - Hang Gong
- Department of Gastroenterology, The Second Clinical Medical College of Lanzhou University, LanZhou University Second Hospital, Lanzhou, China
| | - Dekui Zhang
- Department of Gastroenterology, The Second Clinical Medical College of Lanzhou University, LanZhou University Second Hospital, Lanzhou, China
- Key Laboratory of Digestive Diseases, LanZhou University Second Hospital, Lanzhou, China
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Baskaradoss JK, Behbehani E, Karched M. Effect of Miswak Chewing Sticks on Oral Helicobacter Pylori under both fasting and non-fasting conditions – A preliminary cross-over randomized clinical trial. J Herb Med 2023. [DOI: 10.1016/j.hermed.2023.100646] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/07/2023]
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Helicobacter pylori Chronic-Stage Inflammation Undergoes Fluctuations That Are Altered in tlpA Mutants. Infect Immun 2023; 91:e0032222. [PMID: 36533917 PMCID: PMC9872690 DOI: 10.1128/iai.00322-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Helicobacter pylori colonizes half of the world's population and is responsible for a significant disease burden by causing gastritis, peptic ulcers, and gastric cancer. The development of host inflammation drives these diseases, but there are still open questions in the field about how H. pylori controls this process. We characterized H. pylori inflammation using an 8-month mouse infection time course and comparison of the wild type (WT) and a previously identified mutant lacking the TlpA chemoreceptor that causes elevated inflammation. Our work shows that H. pylori chronic-stage corpus inflammation undergoes surprising fluctuations, with changes in Th17 and eosinophil numbers. The H. pylori tlpA mutant changed the inflammation temporal characteristics, resulting in different inflammation from the wild type at some time points. tlpA mutants have equivalent total and gland colonization in late-stage infections. During early infection, in contrast, they show elevated gland and total colonization compared to those by WT. Our results suggest the chronic inflammation setting is dynamic and may be influenced by colonization properties of early infection.
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Serebrova S, Kurguzova D, Krasnykh L, Vasilenko G, Drozdov V, Lazareva N, Shikh E, Zhuravleva M, Rykova S, Eremenko N, Kareva E, Mirzaev K, Sychev D, Prokofiev A. Potential factors of Helicobacter pylori resistance to clarithromycin. Drug Metab Pers Ther 2022; 37:383-391. [PMID: 36027921 DOI: 10.1515/dmpt-2021-0193] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2021] [Accepted: 03/07/2022] [Indexed: 12/13/2022]
Abstract
OBJECTIVES A comparative dissolution kinetics test (CDKT) and bioequivalence studies of generic proton pump inhibitors (PPIs) do not model pharmacological acid suppression (PAS) and pathological duodenogastric reflux (PDGR). This study aimed to model them in CDKT to assess drugs stability and potential pantoprazole-clarithromycin interactions. METHODS In CDKT, PDGR (dissolution medium pH 7.00 ± 0.05, preexposure at pH 1.20 ± 0.05) and PAS (pH 4.00 ± 0.05) were modelled for original pantoprazole (OP) and its generics (GP1-4). In CDKT with high-performance liquid chromatography, dissolution gastric medium in adequate (pH 4.00 ± 0.05) and inadequate (pH 1.20 ± 0.05) PAS were modelled for original clarithromycin (OC) and its generics (GC1-4). RESULTS After exposure in pH 7.00 ± 0.05, pantoprazole was released from GP1 within 10 min in the amount of 68.8%. In рН 4.00 ± 0.05, 83.0% and 81.5% of pantoprazole were released from GP1 and GP4. When OP, GP2 and GP3 were placed in pH 7.00 ± 0.05, pantoprazole was released in amount: 99.4%, 88.0% and 98.2%. Clarithromycin releasing from OC, GC1, GC2, GC3, GC4 in pH 4.00 ± 0.05 was 93.5%, 91.6%, 92.9%, 79.4% and 83.0%. In pH 1.20 ± 0.05: 9.7%, 6.7%, 8.5%, 33.3%, 28.8%. CONCLUSIONS Destruction of enteric coats of some local pantoprazole generics in CDKT-models might be a potential factor for inadequate therapy.
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Affiliation(s)
- Svetlana Serebrova
- Scientific Centre for Expert Evaluation of Medicinal Products, Moscow, Russian Federation.,I.M. Sechenov First Moscow State Medical University (Sechenov University), Moscow, Russian Federation
| | - Daria Kurguzova
- I.M. Sechenov First Moscow State Medical University (Sechenov University), Moscow, Russian Federation
| | - Lyudmila Krasnykh
- Scientific Centre for Expert Evaluation of Medicinal Products, Moscow, Russian Federation
| | - Galina Vasilenko
- Scientific Centre for Expert Evaluation of Medicinal Products, Moscow, Russian Federation
| | - Vladimir Drozdov
- I.M. Sechenov First Moscow State Medical University (Sechenov University), Moscow, Russian Federation
| | - Natalia Lazareva
- I.M. Sechenov First Moscow State Medical University (Sechenov University), Moscow, Russian Federation
| | - Eugenia Shikh
- Scientific Centre for Expert Evaluation of Medicinal Products, Moscow, Russian Federation.,I.M. Sechenov First Moscow State Medical University (Sechenov University), Moscow, Russian Federation
| | - Marina Zhuravleva
- Scientific Centre for Expert Evaluation of Medicinal Products, Moscow, Russian Federation.,I.M. Sechenov First Moscow State Medical University (Sechenov University), Moscow, Russian Federation
| | - Svetlana Rykova
- I.M. Sechenov First Moscow State Medical University (Sechenov University), Moscow, Russian Federation
| | - Natalia Eremenko
- Scientific Centre for Expert Evaluation of Medicinal Products, Moscow, Russian Federation.,I.M. Sechenov First Moscow State Medical University (Sechenov University), Moscow, Russian Federation
| | - Elena Kareva
- I.M. Sechenov First Moscow State Medical University (Sechenov University), Moscow, Russian Federation
| | - Karin Mirzaev
- Federal State Budgetary Educational Institution of Further Professional Education "Russian Medical Academy of Continuous Professional Education" of The Ministry of Healthcare of The Russian Federation, Moscow, Russian Federation
| | - Dmitriy Sychev
- Federal State Budgetary Educational Institution of Further Professional Education "Russian Medical Academy of Continuous Professional Education" of The Ministry of Healthcare of The Russian Federation, Moscow, Russian Federation
| | - Alexey Prokofiev
- Scientific Centre for Expert Evaluation of Medicinal Products, Moscow, Russian Federation.,I.M. Sechenov First Moscow State Medical University (Sechenov University), Moscow, Russian Federation
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Iwasaki T, Maruyama A, Inui Y, Sakurai T, Kawano T. In vitro transcytosis of Helicobacter pylori histidine-rich protein through gastric epithelial-like cells and the blood-brain barrier. Biosci Biotechnol Biochem 2022; 86:321-330. [PMID: 34935901 DOI: 10.1093/bbb/zbab221] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2021] [Accepted: 12/07/2021] [Indexed: 11/14/2022]
Abstract
Recent epidemiological studies have supported the correlation between Helicobacter pylori infection and the development of Alzheimer's disease. HpHpn, a histidine-rich H. pylori protein, forms amyloid-like oligomers; it may be a pathogenic factor for Alzheimer's disease progression. HpHpn may also be transported from the gastric epithelium to the brain. However, HpHpn is secreted from H. pylori on the outer surface of gastric epithelia; therefore, the hypothesized movement of HpHpn across the gastric epithelium to the blood remains controversial. Here, we found the HpHpn showed acidic pH-dependent cellular uptake and subsequent secretion in human gastric epithelial-like carcinoma cells. Furthermore, HpHpn exhibited in vitro permeability across the blood-brain barrier. Although further in vivo experiments are required, our findings suggest that in vitro transcytosis of HpHpn in gastric epithelial cells and the blood-brain barrier may provide new insights into the correlation between H. pylori infections and Alzheimer's disease progression.
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Affiliation(s)
- Takashi Iwasaki
- Department of Bioresource Science, Faculty of Agriculture, Tottori University, Tottori, Japan
- Department of Agricultural Science, Graduate School of Sustainability Science, Tottori University, Tottori, Japan
| | - Aiki Maruyama
- Department of Bioresource Science, Faculty of Agriculture, Tottori University, Tottori, Japan
| | - Yurika Inui
- Department of Bioresource Science, Faculty of Agriculture, Tottori University, Tottori, Japan
| | - Toshihiko Sakurai
- Department of Chemistry and Biotechnology, Graduate School of Engineering, Tottori University, Tottori, Japan
| | - Tsuyoshi Kawano
- Department of Bioresource Science, Faculty of Agriculture, Tottori University, Tottori, Japan
- Department of Agricultural Science, Graduate School of Sustainability Science, Tottori University, Tottori, Japan
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Swietnicki W. Secretory System Components as Potential Prophylactic Targets for Bacterial Pathogens. Biomolecules 2021; 11:892. [PMID: 34203937 PMCID: PMC8232601 DOI: 10.3390/biom11060892] [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] [Subscribe] [Scholar Register] [Received: 04/22/2021] [Revised: 06/13/2021] [Accepted: 06/14/2021] [Indexed: 01/18/2023] Open
Abstract
Bacterial secretory systems are essential for virulence in human pathogens. The systems have become a target of alternative antibacterial strategies based on small molecules and antibodies. Strategies to use components of the systems to design prophylactics have been less publicized despite vaccines being the preferred solution to dealing with bacterial infections. In the current review, strategies to design vaccines against selected pathogens are presented and connected to the biology of the system. The examples are given for Y. pestis, S. enterica, B. anthracis, S. flexneri, and other human pathogens, and discussed in terms of effectiveness and long-term protection.
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Affiliation(s)
- Wieslaw Swietnicki
- Department of Immunology of Infectious Diseases, Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, ul. R. Weigla 12, 53-114 Wroclaw, Poland
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Effect of pH on the Supramolecular Structure of Helicobacter pylori Urease by Molecular Dynamics Simulations. Polymers (Basel) 2020; 12:polym12112713. [PMID: 33212749 PMCID: PMC7696613 DOI: 10.3390/polym12112713] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Revised: 11/09/2020] [Accepted: 11/11/2020] [Indexed: 12/24/2022] Open
Abstract
The effect of pH on the supramolecular structure of Helicobacter pylori urease was studied by means of molecular dynamics simulations at seven different pHs. Appropriate urease charge distributions were calculated using a semi-grand canonical Monte Carlo (SGCMC) procedure that assigns each residue’s charge state depending on the assigned individual pKa obtained by PROPKA. The effect of pH on protein stability has been analyzed through root-mean-square deviation (RMSD), radius of gyration (RG), solvent-accessible surface area (SASA), hydrogen bonds (HB) and salt bridges (SB). Urease catalyses the hydrolysis of urea in 12 active sites that are covered by mobile regions that act like flaps. The mobility of these flaps is increased at acidic pHs. However, extreme acidic conditions cause urease to have the least number of stabilizing interactions. This initiates the process of denaturalization, wherein the four (αβ)3 subunits of the global structure ((αβ)3)4 of urease start to separate.
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Sukhan DS, Vernygorodskyi SV, Haidukov NV, Ludkevich HP. Molecular and Genetic Aspects of Helicobacter pylori Interaction with Cells of Gastric Mucosa. CYTOL GENET+ 2020. [DOI: 10.3103/s0095452720020139] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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Ji J, Yang H. Using Probiotics as Supplementation for Helicobacter pylori Antibiotic Therapy. Int J Mol Sci 2020; 21:E1136. [PMID: 32046317 PMCID: PMC7037652 DOI: 10.3390/ijms21031136] [Citation(s) in RCA: 64] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Revised: 02/05/2020] [Accepted: 02/07/2020] [Indexed: 02/07/2023] Open
Abstract
Helicobacter pylori is a well-known pathogen that is highly prevalent in the world population, and H. pylori infection is potentially hazardous to humans because of its relationship to various gastrointestinal diseases, such as gastric ulcers, chronic gastritis, and gastric carcinoma. Therefore, the clinical guidelines recommend taking antibiotic therapy to eradicate the pathogen, which usually leads to the desired therapeutic effect. However, some failure cases of this therapy indicate that the increasing antibiotic resistance and side effects may affect the therapeutic effect. Here we propose that using probiotics as supplementation for antibiotic therapy may provide an extra help. Recent studies have shown that probiotic supplementation therapy has promising application prospects; it can enhance the antibiotic effect to achieve a better therapeutic result and maintain the balance of the host gastrointestinal microbiota. In summary, under global conditions of increasing H. pylori prevalence, probiotic supplementation therapy is worthy of further studies for future clinical application.
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Affiliation(s)
| | - Hong Yang
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 201100, China;
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The Interaction of Helicobacter pylori with TFF1 and Its Role in Mediating the Tropism of the Bacteria Within the Stomach. Int J Mol Sci 2019; 20:ijms20184400. [PMID: 31500233 PMCID: PMC6769565 DOI: 10.3390/ijms20184400] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2019] [Revised: 08/27/2019] [Accepted: 09/06/2019] [Indexed: 02/07/2023] Open
Abstract
Helicobacter pylori colonises the human stomach and has tropism for the gastric mucin, MUC5AC. The majority of organisms live in the adherent mucus layer within their preferred location, close to the epithelial surface where the pH is near neutral. Trefoil factor 1 (TFF1) is a small trefoil protein co-expressed with the gastric mucin MUC5AC in surface foveolar cells and co-secreted with MUC5AC into gastric mucus. Helicobacter pylori binds with greater avidity to TFF1 dimer, which is present in gastric mucus, than to TFF1 monomer. Binding of H. pylori to TFF1 is mediated by the core oligosaccharide subunit of H. pylori lipopolysaccharide at pH 5.0–6.0. Treatment of H. pylori lipopolysaccharide with mannosidase or glucosidase inhibits its interaction with TFF1. Both TFF1 and H. pylori have a propensity for binding to mucins with terminal non-reducing α- or β-linked N-acetyl-d-glucosamine or α-(2,3) linked sialic acid or Gal-3-SO42−. These findings are strong evidence that TFF1 has carbohydrate-binding properties that may involve a conserved patch of aromatic hydrophobic residues on the surface of its trefoil domain. The pH-dependent lectin properties of TFF1 may serve to locate H. pylori deep in the gastric mucus layer close to the epithelium rather than at the epithelial surface. This restricted localisation could limit the interaction of H. pylori with epithelial cells and the subsequent host signalling events that promote inflammation.
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Increased anti-Helicobacter pylori effect of the probiotic Lactobacillus fermentum UCO-979C strain encapsulated in carrageenan evaluated in gastric simulations under fasting conditions. Food Res Int 2019; 121:812-816. [DOI: 10.1016/j.foodres.2018.12.064] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2018] [Revised: 12/07/2018] [Accepted: 12/30/2018] [Indexed: 12/14/2022]
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Gonciarz W, Walencka M, Moran AP, Hinc K, Obuchowski M, Chmiela M. Upregulation of MUC5AC production and deposition of LEWIS determinants by HELICOBACTER PYLORI facilitate gastric tissue colonization and the maintenance of infection. J Biomed Sci 2019; 26:23. [PMID: 30841890 PMCID: PMC6402143 DOI: 10.1186/s12929-019-0515-z] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2018] [Accepted: 02/19/2019] [Indexed: 02/07/2023] Open
Abstract
Background Helicobacter pylori bacteria colonize human gastric mucosa, cause chronic inflammation, peptic ulcers and gastric cancer. Colonization is mediated by H. pylori adhesins, which preferentially bind mucin 5 (MUC5AC) and Lewis (Le) determinants. The aim of this study was to evaluate the influence of H. pylori and their components on MUC5AC production and deposition of LeX/LeY in gastric epithelial cells in relation to bacterial adhesion using Caviae porcellus primary gastric epithelial cells and an in vivo model of experimental H. pylori infection in these animals. Methods MUCA5C and LeX/LeY were induced in vitro by live H. pylori reference strain CCUG 17874 (2 × 107 CFU/ml), H. pylori glycine acid extract (GE), 10 μg/ml; cytotoxin associated gene A (CagA) protein, 1 μl/ml; UreA urease subunit, 5 μg/ml; lipopolysaccharide (LPS) 25 ng/ml and imaged by fluorescence microscopy after anti-MUC5AC or anti-LeX/LeY FITC antibody staining. Bacterial adhesion was imaged by using anti-H. pylori FITC antibodies. The animals were inoculated per os with H. pylori (3 times in 2 days intervals, 1 × 1010 CFU/ml). After 7 or 28 days an infection and inflammation were assessed by histological, serological and molecular methods. Gastric tissue sections of infected and control animals were screend for MUCA5C and LeX, and H. pylori adhesion as above. Results MUC5AC production and deposition of Lewis determinants, especially LeX were upregulated in the milieu of live H. pylori as well as GE, CagA, UreA or LPS in vitro and in vivo during infection, more effectively in the acute (7 days) than in the chronic (28 days) phase of infection. This was related to enhanced adhesion of H. pylori, which was abrogated by anti-MUC5AC and anti-LeX or anti-LeY antibody treatment. Conclusions Modulation of MUCA5C production and LeX/LeY deposition in the gastric mucosa by H. pylori can significantly increase gastric tissue colonization during H. pylori infection.
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Affiliation(s)
- Weronika Gonciarz
- Division of Gastroimmunology, Department of Immunology and Infectious Biology, Institute of Microbiology, Biotechnology and Immunology, Faculty of Biology and Environmental Protection, University of Łódź, Banacha 12/16, 90-237, Łódź, Poland
| | - Maria Walencka
- Division of Gastroimmunology, Department of Immunology and Infectious Biology, Institute of Microbiology, Biotechnology and Immunology, Faculty of Biology and Environmental Protection, University of Łódź, Banacha 12/16, 90-237, Łódź, Poland
| | - Anthony P Moran
- Department of Microbiology, School of Natural Sciences, National University of Ireland Galway, Galway, Ireland
| | - Krzysztof Hinc
- Laboratory of Molecular Bacteriology, Intercollegiate Faculty of Biotechnology UG-MUG, Medical University of Gdańsk, 80-210, Gdańsk, Poland
| | - Michał Obuchowski
- Laboratory of Molecular Bacteriology, Intercollegiate Faculty of Biotechnology UG-MUG, Medical University of Gdańsk, 80-210, Gdańsk, Poland
| | - Magdalena Chmiela
- Division of Gastroimmunology, Department of Immunology and Infectious Biology, Institute of Microbiology, Biotechnology and Immunology, Faculty of Biology and Environmental Protection, University of Łódź, Banacha 12/16, 90-237, Łódź, Poland.
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Morey P, Meyer TF. The Sweeping Role of Cholesterol Depletion in the Persistence of Helicobacter pylori Infections. Curr Top Microbiol Immunol 2019; 421:209-227. [PMID: 31123891 DOI: 10.1007/978-3-030-15138-6_9] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The ability of Helicobacter pylori to persist lifelong in the human gastric mucosa is a striking phenomenon. It is even more surprising since infection is typically associated with a vivid inflammatory response. Recent studies revealed the mechanism by which this pathogen inhibits the epithelial responses to IFN-γ and other central inflammatory cytokines in order to abolish an effective antimicrobial defense. The mechanism is based on the modification and depletion of cholesterol by the pathogen's cholesterol-α-glucosyltransferase. It abrogates the assembly of numerous cytokine receptors due to the reduction of lipid rafts. Particularly, the receptors for IFN-γ, IL-22, and IL-6 then fail to assemble properly and to activate JAK/STAT signaling. Consequently, cholesterol depletion prevents the release of antimicrobial peptides, including the highly effective β-defensin-3. Intriguingly, the inhibition is spatially restricted to heavily infected cells, while the surrounding epithelium continues to respond normally to cytokine stimulation, thus providing a platform of the intense inflammation typically observed in H. pylori infections. It appears that pathogen and host establish a homeostatic balance between tightly colonized and rather inflamed sites. This homeostasis is influenced by the levels of available cholesterol, which potentially exacerbate H. pylori-induced inflammation. The observed blockage of epithelial effector mechanisms by H. pylori constitutes a convincing explanation for the previous failures of T-cell-based vaccination against H. pylori, since infected epithelial cells remain inert upon stimulation by effector cytokines. Moreover, the mechanism provides a rationale for the carcinogenic action of this pathogen in that persistent infection and chronic inflammation represent a pro-carcinogenic environment. Thus, cholesterol-α-glucosyltransferase has been revealed as a central pathogenesis determinant of H. pylori.
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Affiliation(s)
- Pau Morey
- Instituto Universitario de Investigación en Ciencias de la Salud (IUNICS), Universidad de las Islas Baleares, Palma de Mallorca, Spain.
| | - Thomas F Meyer
- Department of Molecular Biology, Max Planck Institute for Infection Biology, Berlin, Germany.
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Jie W, Qinghong X, Zhitao C. Association of Helicobacter pylori infection with gastroesophageal reflux disease. J Int Med Res 2018; 47:748-753. [PMID: 30453813 PMCID: PMC6381500 DOI: 10.1177/0300060518809871] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Objective Many studies have shown that Helicobacter pylori (Hp) is negatively correlated with gastroesophageal reflux disease (GERD). Moreover, some studies deny that eradication of Hp increases the incidence of GERD. Therefore, we investigated the association of Hp infection with GERD. Methods In this retrospective analysis, patients with peptic ulcers were used as a blank control group. We used logistic regression to analyze the relationship between Hp infection and GERD. We analyzed 953 patients with peptic ulcers, 180 patients with both peptic ulcers and GERD, and 298 patients with GERD. Results Among the patients with GERD, 75.6% (136/180) and 36.2% (108/298) of those with and without peptic ulcers, respectively, had Hp infection, and the difference was statistically significant. Among patients with peptic ulcers, 75.6% (136/180) and 67.4% (642/953) of those with and without GERD, respectively, had Hp infection. The incidence of GERD in patients with Hp-positive and -negative peptic ulcers was 17.5% (136/778) and 12.4% (44/355), respectively. These differences were also statistically significant. Conclusion In the analysis of patients with GERD, the prevalence of Hp infection was higher among patients with than without peptic ulcers.
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Affiliation(s)
- Wu Jie
- 1 Department of Gastroenterology, The Central Hospital of Wuhan, Tongji Medical College, Huazhong University of Science and Technology; Key Laboratory for Molecular Diagnosis of Hubei Province, The Central Hospital of Wuhan, Tongji Medical College, Huazhong University of Science and Technology; Wuhan, Hubei Province, China.,2 Medical College of Jianghan University, Wuhan, Hubei Province, China
| | - Xu Qinghong
- 1 Department of Gastroenterology, The Central Hospital of Wuhan, Tongji Medical College, Huazhong University of Science and Technology; Key Laboratory for Molecular Diagnosis of Hubei Province, The Central Hospital of Wuhan, Tongji Medical College, Huazhong University of Science and Technology; Wuhan, Hubei Province, China.,2 Medical College of Jianghan University, Wuhan, Hubei Province, China
| | - Chen Zhitao
- 1 Department of Gastroenterology, The Central Hospital of Wuhan, Tongji Medical College, Huazhong University of Science and Technology; Key Laboratory for Molecular Diagnosis of Hubei Province, The Central Hospital of Wuhan, Tongji Medical College, Huazhong University of Science and Technology; Wuhan, Hubei Province, China
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18
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Karkhah A, Ebrahimpour S, Rostamtabar M, Koppolu V, Darvish S, Vasigala VKR, Validi M, Nouri HR. Helicobacter pylori evasion strategies of the host innate and adaptive immune responses to survive and develop gastrointestinal diseases. Microbiol Res 2018; 218:49-57. [PMID: 30454658 DOI: 10.1016/j.micres.2018.09.011] [Citation(s) in RCA: 52] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2018] [Revised: 09/09/2018] [Accepted: 09/28/2018] [Indexed: 02/08/2023]
Abstract
Helicobacter pylori (H. pylori) is a bacterial pathogen that resides in more than half of the human population and has co-evolved with humans for more than 58,000 years. This bacterium is orally transmitted during childhood and is a key cause of chronic gastritis, peptic ulcers and two malignant cancers including MALT (mucosa-associated lymphoid tissue) lymphoma and adenocarcinoma. Despite the strong innate and adaptive immune responses, H. pylori has a long-term survival in the gastric mucosa. In addition to the virulence factors, survival of H. pylori is strongly influenced by the ability of bacteria to escape, disrupt and manipulate the host immune system. This bacterium can escape from recognition by innate immune receptors via altering its surface molecules. Moreover, H. pylori subverts adaptive immune response by modulation of effector T cell. In this review, we discuss the immune-pathogenicity of H. pylori by focusing on its ability to manipulate the innate and acquired immune responses to increase its survival in the gastric mucosa, leading up to gastrointestinal disorders. We also highlight the mechanisms that resulted to the persistence of H. pylori in gastric mucosa.
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Affiliation(s)
- Ahmad Karkhah
- Student Research Committee, Babol University of Medical Sciences, Babol, Iran; Cellular and Molecular Biology Research Center, Health Research Institute, Babol University of Medical Sciences, Babol, Iran
| | - Soheil Ebrahimpour
- Infectious Diseases and Tropical Medicine Research Center, Health Research Institute, Babol University of Medical Sciences, Babol, Iran
| | - Maryam Rostamtabar
- Student Research Committee, Babol University of Medical Sciences, Babol, Iran
| | - Veerendra Koppolu
- Scientist Biopharmaceutical Development Medimmune Gaithersburg, MD, 20878 USA
| | - Sorena Darvish
- Student Research Committee, Babol University of Medical Sciences, Babol, Iran
| | | | - Majid Validi
- Clinical Biochemistry Research Center, Basic Health Sciences Institute, Shahrekord University of Medical Sciences, Shahrekord, Iran
| | - Hamid Reza Nouri
- Cellular and Molecular Biology Research Center, Health Research Institute, Babol University of Medical Sciences, Babol, Iran; Immunoregulation Research Center, Health Research Institute, Babol University of Medical Sciences, Babol, Iran.
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19
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Johnson KS, Ottemann KM. Colonization, localization, and inflammation: the roles of H. pylori chemotaxis in vivo. Curr Opin Microbiol 2017; 41:51-57. [PMID: 29202336 DOI: 10.1016/j.mib.2017.11.019] [Citation(s) in RCA: 72] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2017] [Revised: 10/27/2017] [Accepted: 11/16/2017] [Indexed: 12/18/2022]
Abstract
Helicobacter pylori is a Gram-negative bacterium that infects half of the world's population, causing gastritis, peptic ulcers, and gastric cancer. To establish chronic stomach infection, H. pylori utilizes chemotaxis, driven by a conserved signal transduction system. Chemotaxis allows H. pylori to sense an array of environmental and bacterial signals within the stomach, guiding its motility towards its preferred niche within the gastric mucosa and glands. Fine-tuned localization, regulated by the chemotaxis system, enables robust colonization during the acute stage of infection. During chronic infection, chemotaxis helps maintain bacterial populations and modulates the host immune response. Given its importance in host colonization and disease, chemotaxis is an attractive target for future treatments against H. pylori infections.
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Affiliation(s)
- Kevin S Johnson
- Department of Microbiology and Environmental Toxicology, University of California Santa Cruz, Santa Cruz, CA 95064, USA
| | - Karen M Ottemann
- Department of Microbiology and Environmental Toxicology, University of California Santa Cruz, Santa Cruz, CA 95064, USA.
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20
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Lerner A, Arleevskaya M, Schmiedl A, Matthias T. Microbes and Viruses Are Bugging the Gut in Celiac Disease. Are They Friends or Foes? Front Microbiol 2017; 8:1392. [PMID: 28824555 PMCID: PMC5539691 DOI: 10.3389/fmicb.2017.01392] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2017] [Accepted: 07/10/2017] [Indexed: 12/17/2022] Open
Abstract
The links between microorganisms/viruses and autoimmunity are complex and multidirectional. A huge number of studies demonstrated the triggering impact of microbes and viruses as the major environmental factors on the autoimmune and inflammatory diseases. However, growing evidences suggest that infectious agents can also play a protective role or even abrogate these processes. This protective crosstalk between microbes/viruses and us might represent a mutual beneficial equilibrium relationship between two cohabiting ecosystems. The protective pathways might involve post-translational modification of proteins, decreased intestinal permeability, Th1 to Th2 immune shift, induction of apoptosis, auto-aggressive cells relocation from the target organ, immunosuppressive extracellular vesicles and down regulation of auto-reactive cells by the microbial derived proteins. Our analysis demonstrates that the interaction of the microorganisms/viruses and celiac disease (CD) is always a set of multidirectional processes. A deeper inquiry into the CD interplay with Herpes viruses and Helicobacter pylori demonstrates that the role of these infections, suggested to be potential CD protectors, is not as controversial as for the other infectious agents. The outcome of these interactions might be due to a balance between these multidirectional processes.
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Affiliation(s)
- Aaron Lerner
- The Ruth and Bruce Rappaport Faculty of Medicine, Technion Israel Institute of TechnologyHaifa, Israel.,Department of Research, AESKU.KIPP InstituteWendelsheim, Germany
| | - Marina Arleevskaya
- Central Research Laboratory, Kazan State Medical Academy KazanKazan, Russia
| | - Andreas Schmiedl
- Department of Research, AESKU.KIPP InstituteWendelsheim, Germany
| | - Torsten Matthias
- Department of Research, AESKU.KIPP InstituteWendelsheim, Germany
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21
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Abstract
BACKGROUND Helicobacter pylori is well adapted to colonize the epithelial surface of the human gastric mucosa and can cause persistent infections. In order to infect the gastric mucosa, it has to survive in the gastric acidic pH. This organism has well developed mechanisms to neutralize the effects of acidic pH. OBJECTIVE This review article was designed to summarize the various functional and molecular aspects by which the bacterium can combat and survive the gastric acidic pH in order to establish the persistent infections. METHODS We used the keywords (acid acclimation, gastric acidic environment, H. pylori and survival) in combination or alone for pubmed search of recent scientific literatures. One hundred and forty one papers published between 1989 and 2016 were sorted out. The articles published with only abstracts, other than in English language, case reports and reviews were excluded. RESULTS Many literatures describing the role of several factors in acid survival were found. Recently, the role of several other factors has been claimed to participate in acid survival. CONCLUSION In conclusion, this organism has well characterized mechanisms for acid survival.
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Affiliation(s)
- Shamshul Ansari
- Department of Environmental and Preventive Medicine, Oita University Faculty of Medicine, Yufu, Japan
| | - Yoshio Yamaoka
- Department of Environmental and Preventive Medicine, Oita University Faculty of Medicine, Yufu, Japan,Department of Medicine-Gastroenterology, Baylor College of Medicine, Houston, Texas, USA,Corresponding author: Yoshio Yamaoka, MD, PhD, Department of Environmental and Preventive Medicine, Oita University Faculty of Medicine, 1-1 Idaigaoka, Hasama-machi, Yufu-City, Oita 879-5593, Japan, Tel: +81-97-586-5740; Fax: +81-97-586-5749,
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22
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The Human Stomach in Health and Disease: Infection Strategies by Helicobacter pylori. Curr Top Microbiol Immunol 2017; 400:1-26. [PMID: 28124147 DOI: 10.1007/978-3-319-50520-6_1] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Helicobacter pylori is a bacterial pathogen which commonly colonizes the human gastric mucosa from early childhood and persists throughout life. In the vast majority of cases, the infection is asymptomatic. H. pylori is the leading cause of peptic ulcer disease and gastric cancer, however, and these outcomes occur in 10-15% of those infected. Gastric adenocarcinoma is the third most common cause of cancer-associated death, and peptic ulcer disease is a significant cause of morbidity. Disease risk is related to the interplay of numerous bacterial host and environmental factors, many of which influence chronic inflammation and damage to the gastric mucosa. This chapter summarizes what is known about health and disease in H. pylori infection, and highlights the need for additional research in this area.
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23
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Behrens W, Schweinitzer T, McMurry JL, Loewen PC, Buettner FFR, Menz S, Josenhans C. Localisation and protein-protein interactions of the Helicobacter pylori taxis sensor TlpD and their connection to metabolic functions. Sci Rep 2016; 6:23582. [PMID: 27045738 PMCID: PMC4820699 DOI: 10.1038/srep23582] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2015] [Accepted: 03/09/2016] [Indexed: 12/24/2022] Open
Abstract
The Helicobacter pylori energy sensor TlpD determines tactic behaviour under low energy conditions and is important in vivo. We explored protein-protein interactions of TlpD and their impact on TlpD localisation and function. Pull-down of tagged TlpD identified protein interaction partners of TlpD, which included the chemotaxis histidine kinase CheAY2, the central metabolic enzyme aconitase (AcnB) and the detoxifying enzyme catalase (KatA). We confirmed that KatA and AcnB physically interact with TlpD. While the TlpD-dependent behavioural response appeared not influenced in the interactor mutants katA and acnB in steady-state behavioural assays, acetone carboxylase subunit (acxC) mutant behaviour was altered. TlpD was localised in a bipolar subcellular pattern in media of high energy. We observed a significant change in TlpD localisation towards the cell body in cheAY2-, catalase- or aconitase-deficient bacteria or in bacteria incubated under low energy conditions, including oxidative stress or respiratory inhibition. Inactivation of tlpD resulted in an increased sensitivity to iron limitation and oxidative stress and influenced the H. pylori transcriptome. Oxidative stress, iron limitation and overexpressing the iron-sulfur repair system nifSU altered TlpD-dependent behaviour. We propose that TlpD localisation is instructed by metabolic activity and protein interactions, and its sensory activity is linked to iron-sulfur cluster integrity.
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Affiliation(s)
- Wiebke Behrens
- Institute of Medical Microbiology and Hospital Epidemiology, Hannover Medical School, Hannover, Germany
| | - Tobias Schweinitzer
- Institute of Medical Microbiology and Hospital Epidemiology, Hannover Medical School, Hannover, Germany
| | - Jonathan L McMurry
- Department of Molecular &Cellular Biology, Kennesaw State University, Kennesaw, GA, USA
| | - Peter C Loewen
- Department of Microbiology, University of Manitoba, Winnipeg, Canada
| | - Falk F R Buettner
- Institute for Cellular Chemistry, Hannover Medical School, Hannover, Germany
| | - Sarah Menz
- Institute of Medical Microbiology and Hospital Epidemiology, Hannover Medical School, Hannover, Germany
| | - Christine Josenhans
- Institute of Medical Microbiology and Hospital Epidemiology, Hannover Medical School, Hannover, Germany.,German Center of Infection Research, partner site Hannover-Braunschweig, Germany
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24
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Chang CC, Kuo WS, Chen YC, Perng CL, Lin HJ, Ou YH. Fragmentation of CagA Reduces Hummingbird Phenotype Induction by Helicobactor pylori. PLoS One 2016; 11:e0150061. [PMID: 26934189 PMCID: PMC4775065 DOI: 10.1371/journal.pone.0150061] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2015] [Accepted: 02/09/2016] [Indexed: 12/20/2022] Open
Abstract
Infection with Helicobacter pylori (H. pylori) has been linked to various gastro-intestinal diseases; nevertheless it remains to be clarified why only a minority of infected individuals develop illness. Studies from the West have indicated that the cagA gene and the associated EPIYA genotype of H. pylori is closely linked to the development of severe gastritis and gastric carcinoma; however, as yet no consistent correlation has been found among the bacteria from East Asia. In addition to genotype variation, the CagA protein undergoes fragmentation; however, the functional significance of fragmentation with respect to H. pylori infection remains unknown. In this study, we isolated 594 H. pylori colonies from 99 patients and examined the fragmentation patterns of CagA protein using immunoblotting. By analyzing the ability of the isolates to induce the host cell morphological transition to the highly invasive hummingbird phenotype, we demonstrated that H. pylori colonies with substantial CagA fragmentation are less potent in terms of causing this morphological transition. Our results uncovered a functional role for CagA fragmentation with respect to H. pylori-induced hummingbird phenotype formation and these findings suggest the possibility that the post-translational processing of CagA may be involved in H. pylori infection pathogenesis.
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Affiliation(s)
- Chih-Chi Chang
- Department of Biotechnology and Laboratory Science in Medicine, School of Biomedical Science and Engineering, National Yang-Ming University, Taipei, Taiwan
| | - Wein-Shung Kuo
- Intensive Care Unit, Cheng-Hsin General Hospital, Taipei, Taiwan
| | - Ying-Chieh Chen
- Division of Digestive Medicine, Taipei City Hospital Yangming Branch, Taipei, Taiwan
| | - Chin-Lin Perng
- Division of Gastroenterology, Department of Medicine, VGH-Taipei, Taiwan, and School of Medicine, National Yang-Ming University, Taipei, Taiwan
| | - Hwai-Jeng Lin
- Division of Gastroenterology and Hepatology, Department of Internal Medicine, Taipei Medical University, Shuang-Ho Hospital, New Taipei City, Taiwan, and Division of Gastroenterology and Hepatology, Department of Internal Medicine, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan
- * E-mail: (HJL); (YHO)
| | - Yueh-Hsing Ou
- Department of Biotechnology and Laboratory Science in Medicine, School of Biomedical Science and Engineering, National Yang-Ming University, Taipei, Taiwan
- * E-mail: (HJL); (YHO)
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25
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Keilberg D, Ottemann KM. HowHelicobacter pylorisenses, targets and interacts with the gastric epithelium. Environ Microbiol 2016; 18:791-806. [DOI: 10.1111/1462-2920.13222] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2015] [Revised: 01/05/2016] [Accepted: 01/10/2016] [Indexed: 12/18/2022]
Affiliation(s)
- Daniela Keilberg
- Department of Microbiology and Environmental Toxicology; University of California Santa Cruz; 1156 High Street METX Santa Cruz CA 95064 USA
| | - Karen M. Ottemann
- Department of Microbiology and Environmental Toxicology; University of California Santa Cruz; 1156 High Street METX Santa Cruz CA 95064 USA
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26
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Abstract
Viral and bacterial infections are involved in the development of human cancers, such as liver, nasopharyngeal, cervical, head and neck, and gastric cancers. Aberrant DNA methylation is frequently present in these cancers, and some of the aberrantly methylated genes are causally involved in cancer development and progression. Notably, aberrant DNA methylation can be present even in non-cancerous or precancerous tissues, and its levels correlate with the risk of cancer development, producing a so-called 'epigenetic field for cancerization'. Mechanistically, most viral or bacterial infections induce DNA methylation indirectly via chronic inflammation, but recent studies have indicated that some viruses have direct effects on the epigenetic machinery of host cells. From a translational viewpoint, a recent multicenter prospective cohort study demonstrated that assessment of the extent of alterations in DNA methylation in non-cancerous tissues can be used to predict cancer risk. Furthermore, suppression of aberrant DNA methylation was shown to be a useful strategy for cancer prevention in an animal model. Here, we review the involvement of aberrant DNA methylation in various types of infection-associated cancers, along with individual induction mechanisms, and we discuss the application of these findings for cancer prevention, diagnosis, and therapy.
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Affiliation(s)
- Naoko Hattori
- Division of Epigenomics, National Cancer Center Research Institute, 5-1-1 Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan
| | - Toshikazu Ushijima
- Division of Epigenomics, National Cancer Center Research Institute, 5-1-1 Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan.
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27
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Amieva M, Peek RM. Pathobiology of Helicobacter pylori-Induced Gastric Cancer. Gastroenterology 2016; 150:64-78. [PMID: 26385073 PMCID: PMC4691563 DOI: 10.1053/j.gastro.2015.09.004] [Citation(s) in RCA: 572] [Impact Index Per Article: 71.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/07/2015] [Revised: 09/01/2015] [Accepted: 09/03/2015] [Indexed: 02/07/2023]
Abstract
Colonization of the human stomach by Helicobacter pylori and its role in causing gastric cancer is one of the richest examples of a complex relationship among human cells, microbes, and their environment. It is also a puzzle of enormous medical importance given the incidence and lethality of gastric cancer worldwide. We review recent findings that have changed how we view these relationships and affected the direction of gastric cancer research. For example, recent data have indicated that subtle mismatches between host and microbe genetic traits greatly affect the risk of gastric cancer. The ability of H pylori and its oncoprotein CagA to reprogram epithelial cells and activate properties of stemness show the sophisticated relationship between H pylori and progenitor cells in the gastric mucosa. The observation that cell-associated H pylori can colonize the gastric glands and directly affect precursor and stem cells supports these observations. The ability to mimic these interactions in human gastric organoid cultures as well as animal models will allow investigators to more fully unravel the extent of H pylori control on the renewing gastric epithelium. Finally, our realization that external environmental factors, such as dietary components and essential micronutrients, as well as the gastrointestinal microbiota, can change the balance between H pylori's activity as a commensal or a pathogen has provided direction to studies aimed at defining the full carcinogenic potential of this organism.
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Affiliation(s)
- Manuel Amieva
- Department of Microbiology and Immunology, Stanford University, Palo Alto, California; Department of Pediatrics, Stanford University, Palo Alto, California
| | - Richard M Peek
- Division of Gastroenterology, Hepatology, and Nutrition, Department of Medicine, Vanderbilt University, Nashville, Tennessee; Department of Cancer Biology, Vanderbilt University, Nashville, Tennessee.
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28
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Fontenete S, Leite M, Guimarães N, Madureira P, Ferreira RM, Figueiredo C, Wengel J, Azevedo NF. Towards Fluorescence In Vivo Hybridization (FIVH) Detection of H. pylori in Gastric Mucosa Using Advanced LNA Probes. PLoS One 2015; 10:e0125494. [PMID: 25915865 PMCID: PMC4410960 DOI: 10.1371/journal.pone.0125494] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2014] [Accepted: 03/12/2015] [Indexed: 12/13/2022] Open
Abstract
In recent years, there have been several attempts to improve the diagnosis of infection caused by Helicobacter pylori. Fluorescence in situ hybridization (FISH) is a commonly used technique to detect H. pylori infection but it requires biopsies from the stomach. Thus, the development of an in vivo FISH-based method (FIVH) that directly detects and allows the visualization of the bacterium within the human body would significantly reduce the time of analysis, allowing the diagnosis to be performed during endoscopy. In a previous study we designed and synthesized a phosphorothioate locked nucleic acid (LNA)/ 2’ O-methyl RNA (2’OMe) probe using standard phosphoramidite chemistry and FISH hybridization was then successfully performed both on adhered and suspended bacteria at 37°C. In this work we simplified, shortened and adapted FISH to work at gastric pH values, meaning that the hybridization step now takes only 30 minutes and, in addition to the buffer, uses only urea and probe at non-toxic concentrations. Importantly, the sensitivity and specificity of the FISH method was maintained in the range of conditions tested, even at low stringency conditions (e.g., low pH). In conclusion, this methodology is a promising approach that might be used in vivo in the future in combination with a confocal laser endomicroscope for H. pylori visualization.
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Affiliation(s)
- Sílvia Fontenete
- LEPABE, Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Porto, Portugal
- Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
- IPATIMUP, Institute of Molecular Pathology and Immunology of the University of Porto, Porto, Portugal
- Nucleic Acid Center, Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, Odense M, Denmark
- ICBAS, Institute of Biomedical Sciences Abel Salazar, University of Porto, Porto, Portugal
- * E-mail:
| | - Marina Leite
- Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
- IPATIMUP, Institute of Molecular Pathology and Immunology of the University of Porto, Porto, Portugal
| | - Nuno Guimarães
- LEPABE, Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Porto, Portugal
- Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
- IPATIMUP, Institute of Molecular Pathology and Immunology of the University of Porto, Porto, Portugal
- Nucleic Acid Center, Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, Odense M, Denmark
| | - Pedro Madureira
- Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
- ICBAS, Institute of Biomedical Sciences Abel Salazar, University of Porto, Porto, Portugal
- IBMC, Institute for Molecular Biology and Cell Biology, Porto, Portugal
| | - Rui Manuel Ferreira
- Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
- IPATIMUP, Institute of Molecular Pathology and Immunology of the University of Porto, Porto, Portugal
| | - Céu Figueiredo
- Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
- IPATIMUP, Institute of Molecular Pathology and Immunology of the University of Porto, Porto, Portugal
- FMUP, Faculty of Medicine of Porto University, Porto, Portugal
| | - Jesper Wengel
- IPATIMUP, Institute of Molecular Pathology and Immunology of the University of Porto, Porto, Portugal
| | - Nuno Filipe Azevedo
- LEPABE, Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Porto, Portugal
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Fonseca FM, Etchebehere RM, Queiroz DMDM, Rocha AMC, Junqueira IS, Fonseca DND, Rodrigues ALB, Crema E, de Oliveira AG. Histological and endoscopic features of the stomachs of patients with Chagas disease in the era of Helicobacter pylori. Rev Soc Bras Med Trop 2014; 47:739-46. [DOI: 10.1590/0037-8682-0180-2014] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2014] [Accepted: 11/27/2014] [Indexed: 11/22/2022] Open
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30
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Dunne C, Dolan B, Clyne M. Factors that mediate colonization of the human stomach by Helicobacter pylori. World J Gastroenterol 2014; 20:5610-24. [PMID: 24914320 PMCID: PMC4024769 DOI: 10.3748/wjg.v20.i19.5610] [Citation(s) in RCA: 74] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/25/2013] [Revised: 12/04/2013] [Accepted: 01/19/2014] [Indexed: 02/06/2023] Open
Abstract
Helicobacter pylori (H. pylori) colonizes the stomach of humans and causes chronic infection. The majority of bacteria live in the mucus layer overlying the gastric epithelial cells and only a small proportion of bacteria are found interacting with the epithelial cells. The bacteria living in the gastric mucus may act as a reservoir of infection for the underlying cells which is essential for the development of disease. Colonization of gastric mucus is likely to be key to the establishment of chronic infection. How H. pylori manages to colonise and survive in the hostile environment of the human stomach and avoid removal by mucus flow and killing by gastric acid is the subject of this review. We also discuss how bacterial and host factors may together go some way to explaining the susceptibility to colonization and the outcome of infection in different individuals. H. pylori infection of the gastric mucosa has become a paradigm for chronic infection. Understanding of why H. pylori is such a successful pathogen may help us understand how other bacterial species colonise mucosal surfaces and cause disease.
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Abstract
Some host-adapted bacterial pathogens are capable of causing persistent infections in humans. For example, Helicobacter pylori inhabits the human gastric mucosa and persistence can be lifelong. Salmonella enterica serovar Typhi causes systemic infections that involve colonization of the reticuloendothelial system and some individuals become lifelong carriers. In this review, I compare and contrast the different lifestyles of Helicobacter and Salmonella within the host and the strategies they have evolved to persist in mammalian hosts. Persistently infected carriers serve as the reservoirs for these pathogens, and the carrier state is an essential feature that is required for survival of the bacteria within a restricted host population. Therefore, investigating the chronic carrier state should provide insight into bacterial survival strategies, as well as new therapeutic approaches for treatments.
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Affiliation(s)
- Denise M Monack
- Department of Microbiology and Immunology, Stanford University School of Medicine, Stanford, California 94305
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Bansil R, Celli JP, Hardcastle JM, Turner BS. The Influence of Mucus Microstructure and Rheology in Helicobacter pylori Infection. Front Immunol 2013; 4:310. [PMID: 24133493 PMCID: PMC3794295 DOI: 10.3389/fimmu.2013.00310] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2013] [Accepted: 09/16/2013] [Indexed: 12/24/2022] Open
Abstract
The bacterium Helicobacter pylori (H. pylori), has evolved to survive in the highly acidic environment of the stomach and colonize on the epithelial surface of the gastric mucosa. Its pathogenic effects are well known to cause gastritis, peptic ulcers, and gastric cancer. In order to infect the stomach and establish colonies on the mucus epithelial surface, the bacterium has to move across the gel-like gastric mucus lining of the stomach under acidic conditions. In this review we address the question of how the bacterium gets past the protective mucus barrier from a biophysical perspective. We begin by reviewing the molecular structure of gastric mucin and discuss the current state of understanding concerning mucin polymerization and low pH induced gelation. We then focus on the viscoelasticity of mucin in view of its relevance to the transport of particles and bacteria across mucus, the key first step in H. pylori infection. The second part of the review focuses on the motility of H. pylori in mucin solutions and gels, and how infection with H. pylori in turn impacts the viscoelastic properties of mucin. We present recent microscopic results tracking the motion of H. pylori in mucin solutions and gels. We then discuss how the biochemical strategy of urea hydrolysis required for survival in the acid is also relevant to the mechanism that enables flagella-driven swimming across the mucus gel layer. Other aspects of the influence of H. pylori infection such as, altering gastric mucin expression, its rate of production and its composition, and the influence of mucin on factors controlling H. pylori virulence and proliferation are briefly discussed with references to relevant literature.
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Affiliation(s)
- Rama Bansil
- Department of Physics, Boston University , Boston, MA , USA
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Role of energy sensor TlpD of Helicobacter pylori in gerbil colonization and genome analyses after adaptation in the gerbil. Infect Immun 2013; 81:3534-51. [PMID: 23836820 DOI: 10.1128/iai.00750-13] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Helicobacter pylori maintains colonization in its human host using a limited set of taxis sensors. TlpD is a proposed energy taxis sensor of H. pylori and dominant under environmental conditions of low bacterial energy yield. We studied the impact of H. pylori TlpD on colonization in vivo using a gerbil infection model which closely mimics the gastric physiology of humans. A gerbil-adapted H. pylori strain, HP87 P7, showed energy-dependent behavior, while its isogenic tlpD mutant lost it. A TlpD-complemented strain regained the wild-type phenotype. Infection of gerbils with the complemented strain demonstrated that TlpD is important for persistent infection in the antrum and corpus and suggested a role of TlpD in horizontal navigation and persistent corpus colonization. As a part of the full characterization of the model and to gain insight into the genetic basis of H. pylori adaptation to the gerbil, we determined the complete genome sequences of the gerbil-adapted strain HP87 P7, two HP87 P7 tlpD mutants before and after gerbil passage, and the original human isolate, HP87. The integrity of the genome, including that of a functional cag pathogenicity island, was maintained after gerbil adaptation. Genetic and phenotypic differences between the strains were observed. Major differences between the gerbil-adapted strain and the human isolate emerged, including evidence of recent recombination. Passage of the tlpD mutant through the gerbil selected for gain-of-function variation in a fucosyltransferase gene, futC (HP0093). In conclusion, a gerbil-adapted H. pylori strain with a stable genome has helped to establish that TlpD has important functions for persistent colonization in the stomach.
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Salama NR, Hartung ML, Müller A. Life in the human stomach: persistence strategies of the bacterial pathogen Helicobacter pylori. Nat Rev Microbiol 2013; 11:385-99. [PMID: 23652324 DOI: 10.1038/nrmicro3016] [Citation(s) in RCA: 442] [Impact Index Per Article: 40.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The bacterial pathogen Helicobacter pylori has co-evolved with humans and colonizes approximately 50% of the human population, but only causes overt gastric disease in a subset of infected hosts. In this Review, we discuss the pathogenesis of H. pylori and the mechanisms it uses to promote persistent colonization of the gastric mucosa, with a focus on recent insights into the role of the virulence factors vacuolating cytotoxin (VacA), cytotoxin-associated gene A (CagA) and CagL. We also describe the immunobiology of H. pylori infection and highlight how this bacterium manipulates the innate and adaptive immune systems of the host to promote its own persistence.
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Affiliation(s)
- Nina R Salama
- Division of Human Biology, Fred Hutchinson Cancer Research Center, 1100 Fairview Avenue North, Mailstop C3-168, Seattle, Washington 981091024, USA.
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Alka K, Windle HJ, Cornally D, Ryan BJ, Henehan GTM. A short chain NAD(H)-dependent alcohol dehydrogenase (HpSCADH) from Helicobacter pylori: a role in growth under neutral and acidic conditions. Int J Biochem Cell Biol 2013; 45:1347-55. [PMID: 23583739 DOI: 10.1016/j.biocel.2013.04.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2012] [Revised: 03/27/2013] [Accepted: 04/03/2013] [Indexed: 11/18/2022]
Abstract
Toxic aldehydes produced by alcohol dehydrogenases have been implicated in the pathogenesis of Helicobacter pylori-related damage to the gastric mucosa. Despite this, the enzymes that might be responsible for producing such aldehydes have not been fully described. It was, therefore, of considerable interest to characterize the alcohol oxidizing enzymes in this pathogen. Previous work in this laboratory characterized two such H. pylori enzymes that had broad specificity for a range of aromatic alcohol substrates. However, an enzyme with specificity for aliphatic alcohols is likely to be required in order that H. pylori can metabolize the wide range of substrates encountered in the gastric mucosa. In this study we describe HpSCADH, an alcohol dehydrogenase from H. pylori 26695 with broad specificity for aliphatic alcohols. HpSCADH was classified in the cD1e subfamily of classical short chain alcohol dehydrogenases. The enzyme was a monomer of approximately 29kDa with a preference for NAD(+) as cofactor. Pyrazole was found to be a competitive inhibitor of HpSCADH. The physiological role of this enzyme was explored by construction of an HpSCADH isogenic mutant. At pH 7.0 the mutant showed reduced growth which became more pronounced when the pH was lowered to 5.0. When pyrazole was added to wild type H. pylori cells it caused growth profiles to be reduced to match those of the isogenic mutant suggesting that HpSCADH inhibition alone was responsible for growth impairment. Taken together, the data relating to the alcohol metabolizing enzymes of this pathogen indicate that they play an important role in H. pylori growth and adaptation to acidic environments. The therapeutic potential of targeting H. pylori alcohol dehydrogenases is discussed.
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Affiliation(s)
- Kumari Alka
- School of Food Science and Environmental Health, Dublin Institute of Technology, Marlborough Street, Dublin 1, Ireland
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Effect of gastric environment on Helicobacter pylori adhesion to a mucoadhesive polymer. Acta Biomater 2013; 9:5208-15. [PMID: 22995406 DOI: 10.1016/j.actbio.2012.09.011] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2012] [Revised: 09/10/2012] [Accepted: 09/11/2012] [Indexed: 12/24/2022]
Abstract
Helicobacter pylori infection has been associated with several gastric diseases. This bacterium colonizes the gastric mucosa of half of the world's population, and available treatments are unsuccessful in practically one in every five patients. Mucoadhesive polymers, such as chitosan, are being investigated as gastric drug delivery systems. However, since chitosan is also known for its antimicrobial properties, this work aims to evaluate H. pylori interactions with chitosan under simulated gastric environments, namely using various pHs (2.6, 4 and 6), pepsin and urea. To enable the visualization of adherent bacteria, ultrathin chitosan films were produced by spin-coating on gold/glass surfaces, cross-linked with genipin and characterized by Fourier transform infrared reflection absorption spectroscopy, ellipsometry and electrokinetic analysis. Films with homogeneous thickness of 11.7±0.6 nm were produced, and were stable and protonated at all the pHs used. Furthermore, they adsorbed pepsin in all these pHs, in contrast to urea, of which a small adsorption was only observed at pH 6. H. pylori binding to chitosan was higher at pH2.6 although most of adherent bacteria were dead. The presence of pepsin decreased bacterial adhesion, but increased its viability while in a more stressed morphology (coccoid form). The presence of urea did not affect the amount, morphology or viability of chitosan-adherent bacteria. In suspension, the decrease in pH changed H. pylori zeta potential from negative to positive. Moreover, bacteria were only culturable when incubated in pH 6 with and without urea (without pepsin). This work demonstrates that chitosan has the capacity to bind and kill H. pylori in a range of pHs independently of urea. This opens new perspectives for the application of chitosan-based materials to the elimination of H. pylori gastric colonization, though pepsin might appear to be an obstacle.
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Bücker R, Azevedo-Vethacke M, Groll C, Garten D, Josenhans C, Suerbaum S, Schreiber S. Helicobacter pylori colonization critically depends on postprandial gastric conditions. Sci Rep 2012; 2:994. [PMID: 23251780 PMCID: PMC3524519 DOI: 10.1038/srep00994] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2012] [Accepted: 11/28/2012] [Indexed: 12/14/2022] Open
Abstract
The risk of Helicobacter pylori infection is highest in childhood, but the colonization process of the stomach mucosa is poorly understood. We used anesthetized Mongolian gerbils to study the initial stages of H. pylori colonization. Prandial and postprandial gastric conditions characteristic of humans of different ages were simulated. The fraction of bacteria that reached the deep mucus layer varied strongly with the modelled postprandial conditions. Colonization success was weak with fast gastric reacidification typical of adults. The efficiency of deep mucus entry was also low with a slow pH decrease as seen in pH profiles simulating the situation in babies. Initial colonization was most efficient under conditions simulating the postprandial reacidification and pepsin activation profiles in young children. In conclusion, initial H. pylori colonization depends on age-related gastric physiology, providing evidence from an in vivo infection model that suggests an explanation why the bacterium is predominantly acquired in early childhood.
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Affiliation(s)
- Roland Bücker
- Institut für Physiologie, Ruhr-Universität Bochum, Im Lottental 36, 44801 Bochum, Germany
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Tsang J, Smith TG, Pereira LE, Hoover TR. Insertion mutations in Helicobacter pylori flhA reveal strain differences in RpoN-dependent gene expression. MICROBIOLOGY-SGM 2012; 159:58-67. [PMID: 23154969 DOI: 10.1099/mic.0.059063-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Flagellar biogenesis in the gastric pathogen Helicobacter pylori involves a transcriptional hierarchy that utilizes all three sigma factors found in this bacterium (RpoD, RpoN and FliA). Transcription of the RpoN-dependent genes requires the sensor kinase FlgS and response regulator FlgR. It is thought that FlgS senses some cellular cue to regulate transcription of the RpoN-dependent flagellar genes, but this signal has yet to be identified. Previous studies showed that transcription of the RpoN-dependent genes is inhibited by mutations in flhA, which encodes a membrane-bound component of the flagellar protein export apparatus. We found that depending on the H. pylori strain used, insertion mutations in flhA had different effects on expression of RpoN-dependent genes. Mutations in flhA in H. pylori strains B128 and ATCC 43504 (the type strain) were generated by inserting a chloramphenicol resistance cassette so as to effectively eliminate expression of the gene (ΔflhA), or within the gene following codon 77 (designated flhA77) or codon 454 (designated flhA454), which could allow expression of truncated FlhA proteins. All three flhA mutations severely inhibited transcription of the RpoN-dependent genes flaB and flgE in H. pylori B128. In contrast, levels of flaB and flgE transcripts in H. pylori ATCC 43504 bearing either flhA77 or flhA454, but not ΔflhA, were ~60 % of wild-type levels. The FlhA(454) variant was detected in membrane fractions prepared from H. pylori ATCC 43504 but not H. pylori B128, which may account for the phenotypic differences in the flhA mutations of the two strains. Taken together, these findings suggest that only the N-terminal region of FlhA is needed for transcription of the RpoN regulon. Interestingly, expression of an flaB'-'xylE reporter gene in H. pylori ATCC 43504 bearing the flhA77 allele was about eightfold higher than that of a strain with the wild-type allele, suggesting that expression of flaB is not only regulated at the level of transcription but also regulated post-transcriptionally.
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Affiliation(s)
- Jennifer Tsang
- Department of Microbiology, University of Georgia, Athens, GA 30602, USA
| | - Todd G Smith
- Department of Microbiology, University of Georgia, Athens, GA 30602, USA
| | - Lara E Pereira
- Department of Microbiology, University of Georgia, Athens, GA 30602, USA
| | - Timothy R Hoover
- Department of Microbiology, University of Georgia, Athens, GA 30602, USA
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Fonseca FM, Queiroz DMDM, Rocha AMC, Prata A, Crema E, Rodrigues Junior V, Ramirez LE, Oliveira AGD. Seroprevalence of Helicobacter pylori infection in chagasic and nonchagasic patients from the same geographical region of Brazil. Rev Soc Bras Med Trop 2012; 45:194-8. [PMID: 22534991 DOI: 10.1590/s0037-86822012000200011] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2011] [Accepted: 09/30/2011] [Indexed: 11/22/2022] Open
Abstract
INTRODUCTION In this study, we evaluated the seroprevalence of Helicobacter pylori infection among chagasic and non-chagasic subjects as well as among the subgroups of chagasic patients with the indeterminate, cardiac, digestive, and cardiodigestive clinical forms. METHODS The evaluated subjects were from the Triângulo Mineiro region, Minas Gerais, Brazil. Chagasic patients showed positive reactions to the conventional serological tests used and were classified according to the clinical form of their disease. Immunoglobulin G antibodies specific to H. pylori were measured using a commercial enzyme-linked immunosorbent assay kit. RESULTS The overall H. pylori prevalence was 77.1% (239/310) in chagasic and 69.1% (168/243) in non-chagasic patients. This difference was statistically significant even after adjustment for age and sex (odds ratio = 1.57; 95% confidence interval, 1.02-2.42; p = 0.04) in multivariate analysis. The prevalence of infection increased with age in the non-chagasic group (p = 0.007, χ² for trend), but not in the chagasic group (p = 0.15, χ² for trend). H. pylori infection was not associated with digestive or other clinical forms of Chagas disease (p = 0.27). CONCLUSIONS Our findings demonstrate that chagasic patients have a higher prevalence of H. pylori compared to non-chagasic subjects; a similar prevalence was found among the diverse clinical forms of the disease. The factors contributing to the frequent co-infection with H. pylori and Trypanosoma cruzi as well as its effects on the clinical outcome deserve further study.
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Chaperone-dependent mechanisms for acid resistance in enteric bacteria. Trends Microbiol 2012; 20:328-35. [DOI: 10.1016/j.tim.2012.03.001] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2011] [Revised: 02/26/2012] [Accepted: 03/02/2012] [Indexed: 01/13/2023]
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Sycuro LK, Wyckoff TJ, Biboy J, Born P, Pincus Z, Vollmer W, Salama NR. Multiple peptidoglycan modification networks modulate Helicobacter pylori's cell shape, motility, and colonization potential. PLoS Pathog 2012; 8:e1002603. [PMID: 22457625 PMCID: PMC3310797 DOI: 10.1371/journal.ppat.1002603] [Citation(s) in RCA: 106] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2011] [Accepted: 01/05/2012] [Indexed: 12/14/2022] Open
Abstract
Helical cell shape of the gastric pathogen Helicobacter pylori has been suggested to promote virulence through viscosity-dependent enhancement of swimming velocity. However, H. pylori csd1 mutants, which are curved but lack helical twist, show normal velocity in viscous polymer solutions and the reason for their deficiency in stomach colonization has remained unclear. Characterization of new rod shaped mutants identified Csd4, a DL-carboxypeptidase of peptidoglycan (PG) tripeptide monomers and Csd5, a putative scaffolding protein. Morphological and biochemical studies indicated Csd4 tripeptide cleavage and Csd1 crosslinking relaxation modify the PG sacculus through independent networks that coordinately generate helical shape. csd4 mutants show attenuation of stomach colonization, but no change in proinflammatory cytokine induction, despite four-fold higher levels of Nod1-agonist tripeptides in the PG sacculus. Motility analysis of similarly shaped mutants bearing distinct alterations in PG modifications revealed deficits associated with shape, but only in gel-like media and not viscous solutions. As gastric mucus displays viscoelastic gel-like properties, our results suggest enhanced penetration of the mucus barrier underlies the fitness advantage conferred by H. pylori's characteristic shape.
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Affiliation(s)
- Laura K. Sycuro
- Molecular and Cellular Biology Graduate Program, Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
- Division of Human Biology, Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
| | - Timna J. Wyckoff
- Division of Human Biology, Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
- Division of Science and Mathematics, University of Minnesota, Morris, Minnesota, United States of America
| | - Jacob Biboy
- Centre for Bacterial Cell Biology, Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Petra Born
- Centre for Bacterial Cell Biology, Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Zachary Pincus
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, Connecticut, United States of America
| | - Waldemar Vollmer
- Centre for Bacterial Cell Biology, Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Nina R. Salama
- Molecular and Cellular Biology Graduate Program, Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
- * E-mail:
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Lara-Ramírez EE, Segura-Cabrera A, Guo X, Yu G, García-Pérez CA, Rodríguez-Pérez MA. New implications on genomic adaptation derived from the Helicobacter pylori genome comparison. PLoS One 2011; 6:e17300. [PMID: 21387011 PMCID: PMC3046158 DOI: 10.1371/journal.pone.0017300] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2010] [Accepted: 01/28/2011] [Indexed: 02/07/2023] Open
Abstract
Background Helicobacter pylori has a reduced genome and lives in a tough environment for long-term persistence. It evolved with its particular characteristics for biological adaptation. Because several H. pylori genome sequences are available, comparative analysis could help to better understand genomic adaptation of this particular bacterium. Principal Findings We analyzed nine H. pylori genomes with emphasis on microevolution from a different perspective. Inversion was an important factor to shape the genome structure. Illegitimate recombination not only led to genomic inversion but also inverted fragment duplication, both of which contributed to the creation of new genes and gene family, and further, homological recombination contributed to events of inversion. Based on the information of genomic rearrangement, the first genome scaffold structure of H. pylori last common ancestor was produced. The core genome consists of 1186 genes, of which 22 genes could particularly adapt to human stomach niche. H. pylori contains high proportion of pseudogenes whose genesis was principally caused by homopolynucleotide (HPN) mutations. Such mutations are reversible and facilitate the control of gene expression through the change of DNA structure. The reversible mutations and a quasi-panmictic feature could allow such genes or gene fragments frequently transferred within or between populations. Hence, pseudogenes could be a reservoir of adaptation materials and the HPN mutations could be favorable to H. pylori adaptation, leading to HPN accumulation on the genomes, which corresponds to a special feature of Helicobacter species: extremely high HPN composition of genome. Conclusion Our research demonstrated that both genome content and structure of H. pylori have been highly adapted to its particular life style.
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Affiliation(s)
| | - Aldo Segura-Cabrera
- Centro de Biotecnología Genómica, Instituto Politécnico Nacional, Reynosa, México
| | - Xianwu Guo
- Centro de Biotecnología Genómica, Instituto Politécnico Nacional, Reynosa, México
- * E-mail:
| | - Gongxin Yu
- Department of Biological Sciences, Boise State University, Boise, Idaho, United States of America
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Increase in acid tolerance of Campylobacter jejuni through coincubation with amoebae. Appl Environ Microbiol 2010; 76:4194-200. [PMID: 20453130 DOI: 10.1128/aem.01219-09] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Campylobacter jejuni is a recognized and common gastrointestinal pathogen in most parts of the world. Human infections are often food borne, and the bacterium is frequent among poultry and other food animals. However, much less is known about the epidemiology of C. jejuni in the environment and what mechanisms the bacterium depends on to tolerate low pH. The sensitive nature of C. jejuni stands in contrast to the fact that it is difficult to eradicate from poultry production, and even more contradictory is the fact that the bacterium is able to survive the acidic passage through the human stomach. Here we expand the knowledge on C. jejuni acid tolerance by looking at protozoa as a potential epidemiological pathway of infection. Our results showed that when C. jejuni cells were coincubated with Acanthamoeba polyphaga in acidified phosphate-buffered saline (PBS) or tap water, the bacteria could tolerate pHs far below those in their normal range, even surviving at pH 4 for 20 h and at pH 2 for 5 h. Interestingly, moderately acidic conditions (pH 4 and 5) were shown to trigger C. jejuni motility as well as to increase adhesion/internalization of bacteria into A. polyphaga. Taken together, the results suggest that protozoa may act as protective hosts against harsh conditions and might be a potential risk factor for C. jejuni infections. These findings may be important for our understanding of C. jejuni passage through the gastrointestinal tract and for hygiene practices used in poultry settings.
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Schweinitzer T, Josenhans C. Bacterial energy taxis: a global strategy? Arch Microbiol 2010; 192:507-20. [PMID: 20411245 PMCID: PMC2886117 DOI: 10.1007/s00203-010-0575-7] [Citation(s) in RCA: 73] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2010] [Revised: 03/31/2010] [Accepted: 04/06/2010] [Indexed: 12/24/2022]
Abstract
A functional energy metabolism is one of the most important requirements for survival of all kinds of organisms including bacteria. Therefore, many bacteria actively seek conditions of optimal metabolic activity, a behaviour which can be termed "energy taxis". Motility, combined with the sensory perception of the internal energetic conditions, is prerequisite for tactic responses to different energy levels and metabolic yields. Diverse mechanisms of energy sensing and tactic response have evolved among various bacteria. Many of the known energy taxis sensors group among the methyl-accepting chemotaxis protein (MCP)-like sensors. This review summarizes recent advances in the field of energy taxis and explores the current concept that energy taxis is an important part of the bacterial behavioural repertoire in order to navigate towards more favourable metabolic niches and to survive in a specific habitat.
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Affiliation(s)
- Tobias Schweinitzer
- Institute for Medical Microbiology and Hospital Epidemiology, Hannover Medical School, Carl-Neuberg-Strasse 1, 30625 Hannover, Germany
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Hu L, Liu L, Tan QH, Zhou L, Chen ZH, Liu YL. Isolation and culture of clinical strains of Helicobacter pylori from patients in Guizhou Province. Shijie Huaren Xiaohua Zazhi 2009; 17:2830-2834. [DOI: 10.11569/wcjd.v17.i27.2830] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM: To isolate and culture the clinical strains of Helicobacter pylori (H. pylori) from patients in Guizhou Province, and to determine the clinical features of patients from whom H. pylori strains were isolated and cultured successfully.
METHODS: Ninety-eight patients suffering from upper gastrointestinal symptoms underwent antral biopsy for isolation and culture of H. pylori strains. The ethnic group, disease, age, gender, and family history of gastritis or H. pylori were compared among patients who were positive for H. pylori.
RESULTS: The total positive rate of H. pylori was 38% (37/98). No significant difference was noted in the positive rate of
H. pylori between Han ethnic patients 36% (29/80) and other minority ethnic patients (36% vs 44%, P > 0.05). However, the positive rate of H. pylori in Miao ethnic patients was significantly higher than that in Han ethnic patients (P < 0.05). The positive rates of H. pylori in patients with erosive gastritis (39%, 11/28) and peptic ulcer (46%, 24/52) were significantly higher than that in patients suffering from gastritis or gastric cancer (both P < 0.05). The positive rate of H. pylori was significantly higher in patients aged 30-60 years than in patients aged 60-80 years (45% vs 21%, P < 0.05). The positive rate of H. pyloriwas significantly higher in male patients than in female ones (48% vs 24%, P < 0.05). No significant difference was noted in the positive rate of H. pylori between patients with and without a family history of gastritis.
CONCLUSION: This study represents the first successful isolation and culture of clinical strains of H. pylori from patients in Guizhou province, which provides a basis for future basic and clinical research of H. pylori infection in this area.
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Fischer W, Prassl S, Haas R. Virulence Mechanisms and Persistence Strategies of the Human Gastric Pathogen Helicobacter pylori. Curr Top Microbiol Immunol 2009; 337:129-71. [DOI: 10.1007/978-3-642-01846-6_5] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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Specific therapeutic schemes of omeprazole affect the orientation of Helicobacter pylori. Antimicrob Agents Chemother 2009; 53:3511-4. [PMID: 19487446 DOI: 10.1128/aac.00158-09] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Until now, it has been unclear how proton pump inhibitors (PPIs) support Helicobacter pylori therapy. We tested whether the PPI omeprazole acts on the spatial orientation of H. pylori in the gastric mucus of infected Mongolian gerbils. Following repetitive PPI administration once daily but not following single doses or administration every 8 h, the bacterial spatial distribution changed, indicating a loss of orientation. Therefore, the therapeutic scheme of PPI administration may affect efficiency of treatment.
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Amieva MR, El-Omar EM. Host-bacterial interactions in Helicobacter pylori infection. Gastroenterology 2008; 134:306-23. [PMID: 18166359 DOI: 10.1053/j.gastro.2007.11.009] [Citation(s) in RCA: 370] [Impact Index Per Article: 23.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/21/2007] [Accepted: 10/21/2007] [Indexed: 02/07/2023]
Abstract
Helicobacter pylori are spiral-shaped gram-negative bacteria with polar flagella that live near the surface of the human gastric mucosa. They have evolved intricate mechanisms to avoid the bactericidal acid in the gastric lumen and to survive near, to attach to, and to communicate with the human gastric epithelium and host immune system. This interaction sometimes results in severe gastric pathology. H pylori infection is the strongest known risk factor for the development of gastroduodenal ulcers, with infection being present in 60%-80% of gastric and 95% of duodenal ulcers.(1)H pylori is also the first bacterium to be classified as a definite carcinogen by the World Health Organization's International Agency for Research on Cancer because of its epidemiologic relationship to gastric adenocarcinoma and gastric mucosa-associated lymphoid tissue lymphoma.(2) In the last 25 years, since H pylori was first described and cultured, a complete paradigm shift has occurred in our clinical approach to these gastric diseases, and more than 20,000 scientific publications have appeared on the subject. From the medical point of view, H pylori is a formidable pathogen responsible for much morbidity and mortality worldwide. However, H pylori infection occurs in approximately half of the world population, with disease being an exception rather than the rule. Understanding how this organism interacts with its host is essential for formulating an intelligent strategy for dealing with its most important clinical consequences. This review offers an insight into H pylori host-bacterial interactions.
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Affiliation(s)
- Manuel R Amieva
- Department of Microbiology and Immunology, Stanford University School of Medicine, Stanford, California, USA
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O'Gara EA, Maslin DJ, Nevill AM, Hill DJ. The effect of simulated gastric environments on the anti-Helicobacter activity of garlic oil. J Appl Microbiol 2007; 104:1324-31. [PMID: 18028365 DOI: 10.1111/j.1365-2672.2007.03637.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
AIMS To investigate the effects of simulated gastric conditions upon the anti-Helicobacter pylori effects of garlic oil (GO). METHODS AND RESULTS Time course viability experiments assessed the anti-H. pylori activity of GO (16 and 32 microg ml(-1)) in simulated gastric environments. Rapid anti-H. pylori action of GO was observed in artificial gastric juice. Mucus (1-5%) was strongly protective of H. pylori both alone and in the presence of GO, but its protective effect was antagonized by GO. Peptone (5-15 g l(-1)) caused a dose-dependent reduction in the anti-H. pylori activity of GO. Rapeseed oil (5.7-17 g l(-1)) greatly diminished the anti-H. pylori activity of GO. Dextrin (44 and 133 g l(-1)) exhibited direct anti-H. pylori effects and added to those of GO. Simulated meal mixtures decreased but did not eliminate the anti-H. pylori activity of 32 mug ml(-1) GO. CONCLUSIONS The anti-H. pylori activity of GO was noticeably affected by food materials and mucin. However, substantial activity remained under simulated gastric conditions. Further investigation of the therapeutic potential of GO against H. pylori is therefore warranted. SIGNIFICANCE AND IMPACT OF THE STUDY Garlic oil may be useful as an alternative treatment against H. pylori, a major cause of gastrointestinal infections in humans.
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Affiliation(s)
- E A O'Gara
- Research Institute in Healthcare Science, University of Wolverhampton, School of Applied Sciences, Wolverhampton, United Kingdom.
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Clyne M, Dolan B, Reeves EP. Bacterial factors that mediate colonization of the stomach and virulence of Helicobacter pylori. FEMS Microbiol Lett 2007; 268:135-43. [PMID: 17313591 DOI: 10.1111/j.1574-6968.2007.00648.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Helicobacter pylori is a Gram-negative microaerophilic organism that colonizes the gastric mucosa of humans. Helicobacter pylori is one of the most common infections in humans and results in the development of gastritis in all infected individuals, although the majority of people are asymptomatic. A subset of infected people develop serious disease including duodenal ulceration and gastric cancer. Helicobacter pylori exhibits many striking characteristics. It lives in the hostile environment of the stomach and displays a very strict host and tissue tropism. Despite a vigorous immune response, infection persists for the lifetime of the host unless eradicated with antimicrobials. Why H. pylori is so pathogenic in some individuals and not in others is unknown but is thought to be due to a variety of host, environmental and bacterial factors. In this review, some of the bacterial factors that mediate colonization of the gastric mucosa and play a role in the pathogenesis of this organism have been considered.
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Affiliation(s)
- Marguerite Clyne
- UCD School of Medicine and Medical Science, The Children's Research Ctr, Our Lady's Children's Hospital Crumlin, Dublin, Ireland.
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