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Jarzab M, Skorko-Glonek J. There Are No Insurmountable Barriers: Passage of the Helicobacter pylori VacA Toxin from Bacterial Cytoplasm to Eukaryotic Cell Organelle. Membranes (Basel) 2023; 14:11. [PMID: 38248700 PMCID: PMC10821523 DOI: 10.3390/membranes14010011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2023] [Revised: 12/20/2023] [Accepted: 12/23/2023] [Indexed: 01/23/2024]
Abstract
The Gram-negative bacterium Helicobacter pylori is a very successful pathogen, one of the most commonly identified causes of bacterial infections in humans worldwide. H. pylori produces several virulence factors that contribute to its persistence in the hostile host habitat and to its pathogenicity. The most extensively studied are cytotoxin-associated gene A (CagA) and vacuolating cytotoxin A (VacA). VacA is present in almost all H. pylori strains. As a secreted multifunctional toxin, it assists bacterial colonization, survival, and proliferation during long-lasting infections. To exert its effect on gastric epithelium and other cell types, VacA undergoes several modifications and crosses multiple membrane barriers. Once inside the gastric epithelial cell, VacA disrupts many cellular-signaling pathways and processes, leading mainly to changes in the efflux of various ions, the depolarization of membrane potential, and perturbations in endocytic trafficking and mitochondrial function. The most notable effect of VacA is the formation of vacuole-like structures, which may lead to apoptosis. This review focuses on the processes involved in VacA secretion, processing, and entry into host cells, with a particular emphasis on the interaction of the mature toxin with host membranes and the formation of transmembrane pores.
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Affiliation(s)
| | - Joanna Skorko-Glonek
- Department of General and Medical Biochemistry, Faculty of Biology, University of Gdansk, Wita Stwosza 59, 80-308 Gdansk, Poland;
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Atanda H, Balogun TA, Alshehri MM, Olivos-Ramirez G, Vilca-Quispe J, Chenet-Zuta M, Cárdenas-Cárdenas R, Delgado Wong H, Ropón-Palacios G, Umar HI. In silico study revealed the inhibitory activity of selected phytomolecules of C. rotundus against VacA implicated in gastric ulcer. J Biomol Struct Dyn 2023; 41:10713-10724. [PMID: 36571437 DOI: 10.1080/07391102.2022.2160814] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2022] [Accepted: 12/07/2022] [Indexed: 12/27/2022]
Abstract
Gastric ulcer is associated with weakening of the mucous coating of the stomach and damages to the intestinal lining. It is caused by H. pylori assisted by enzymes including VacA, which necessitates the need for inhibitors of VacA. Bioactive compounds from Cyperus rotundus have been documented to have anti-inflammatory activities. However, the mechanism of action of the phytochemicals is not characterized. This research aimed to assess, in silico, the potential of selected bioactive compounds against VacA based on the binding to its active sites. VacA and bioactive compounds structures were obtained from protein database and PubChem webserver, respectively. All compounds, including 2 controls, omeprazole and cimetidine were docked against the protein using AutoDock Vina and screened based on the binding energy. The selected complexes were subjected to pharmacokinetics and toxicity screening. Finally, molecular dynamics simulation and MMPBSA were carried out on two best compounds. 17 compounds interacted with the active site of VacA with higher binding affinities, with 7 of them - aureusidine, catechin, chlorogenic acid, isorhamnetin, isovitexin, oreintin, and vitexin having the best behaviours based on ADMET and druglikeness screening. Molecular dynamics and MMPBSA experiments of two of the hits corroborated good stability and binding energy for Ellagic Acid and Scirpusin B (ΔG = -14.38 and -13.20 kcal mol-1, respectively). These phytochemicals showed good pharmacokinetic profiles with respect to the control drugs. This study revealed that the identified compounds of C. rotundus may serve as VacA inhibitors and may be potent candidates for novel drug formulations in gastric ulcer treatment.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Halimat Atanda
- Department of Biotechnology, Federal University of Technology, Akure, Ondo State, Nigeria
- Computer-Aided Therapeutic Discovery and Design Group, FUTA, Akure, Ondo State, Nigeria
| | - Toheeb Adewale Balogun
- Computer-Aided Therapeutic Discovery and Design Group, FUTA, Akure, Ondo State, Nigeria
- Department of Biochemistry, Adekunle Ajasin University, Akungba-Akoko, Ondo State, Nigeria
| | - Mohammed M Alshehri
- Pharmaceutical Care Department, Ministry of National Guard-Health Affairs, Riyadh, Saudi Arabia
| | - Gustavo Olivos-Ramirez
- Laboratório de Modelagem Computacional - LaModel, Instituto de Ciências Exatas - ICEx, Universidade Federal de Alfenas - UNIFAL-MG, Alfenas, Brasil
| | - Julissa Vilca-Quispe
- Laboratório de Modelagem Computacional - LaModel, Instituto de Ciências Exatas - ICEx, Universidade Federal de Alfenas - UNIFAL-MG, Alfenas, Brasil
| | - Manuel Chenet-Zuta
- Universidad Nacional Tecnológica de Lima Sur UNTELS, Villa el Salvador, Perú
| | - Reyna Cárdenas-Cárdenas
- Facultad de Farmacia y Bioquímica, Universidad Nacional de la Amazonía Peruana, Iquitos, Peru
| | - Henry Delgado Wong
- Laboratorio de Farmacología y Toxicología de la Facultad de Farmacia y Bioquímica de la Universidad Nacional de la Amazonia Peruana, Villa el Salvador, Perú
| | - Georcki Ropón-Palacios
- Laboratório de Modelagem Computacional - LaModel, Instituto de Ciências Exatas - ICEx, Universidade Federal de Alfenas - UNIFAL-MG, Alfenas, Brasil
| | - Haruna Isiyaku Umar
- Computer-Aided Therapeutic Discovery and Design Group, FUTA, Akure, Ondo State, Nigeria
- Department of Biochemistry, Federal University of Technology, Akure, Ondo State, Nigeria
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Seeger AY, Zaidi F, Alhayek S, Jones RM, Zohair H, Holland RL, Kim IJ, Blanke SR. Host cell sensing and restoration of mitochondrial function and metabolism within Helicobacter pylori VacA intoxicated cells. mBio 2023; 14:e0211723. [PMID: 37815365 PMCID: PMC10653863 DOI: 10.1128/mbio.02117-23] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2023] [Accepted: 08/23/2023] [Indexed: 10/11/2023] Open
Abstract
IMPORTANCE Persistent human gastric infection with Helicobacter pylori is the single most important risk factor for development of gastric malignancy, which is one of the leading causes of cancer-related deaths worldwide. An important virulence factor for Hp colonization and severity of gastric disease is the protein exotoxin VacA, which is secreted by the bacterium and modulates functional properties of gastric cells. VacA acts by damaging mitochondria, which impairs host cell metabolism through impairment of energy production. Here, we demonstrate that intoxicated cells have the capacity to detect VacA-mediated damage, and orchestrate the repair of mitochondrial function, thereby restoring cellular health and vitality. This study provides new insights into cellular recognition and responses to intracellular-acting toxin modulation of host cell function, which could be relevant for the growing list of pathogenic microbes and viruses identified that target mitochondria as part of their virulence strategies.
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Affiliation(s)
- Ami Y. Seeger
- Department of Microbiology, University of Illinois, Urbana, Illinois, USA
| | - Faisal Zaidi
- Department of Microbiology, University of Illinois, Urbana, Illinois, USA
| | - Sammy Alhayek
- Department of Microbiology, University of Illinois, Urbana, Illinois, USA
| | - Rachel M. Jones
- Department of Microbiology, University of Illinois, Urbana, Illinois, USA
| | - Huzaifa Zohair
- Department of Microbiology, University of Illinois, Urbana, Illinois, USA
| | - Robin L. Holland
- Department of Pathobiology, University of Illinois, Urbana, Illinois, USA
| | - Ik-Jung Kim
- Department of Microbiology, University of Illinois, Urbana, Illinois, USA
- Buck Institute for Research on Aging, Novato, California, USA
| | - Steven R. Blanke
- Department of Microbiology, University of Illinois, Urbana, Illinois, USA
- Department of Pathobiology, University of Illinois, Urbana, Illinois, USA
- Department of Biomedical and Translational Medicine, University of Illinois, Urbana, Illinois, USA
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Holland RL, Bosi KD, Seeger AY, Blanke SR. Restoration of mitochondrial structure and function within Helicobacter pylori VacA intoxicated cells. Adv Microbiol 2023; 13:399-419. [PMID: 37654621 PMCID: PMC10470862 DOI: 10.4236/aim.2023.138026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/02/2023]
Abstract
The Helicobacter pylori vacuolating cytotoxin (VacA) is an intracellular, mitochondrial-targeting exotoxin that rapidly causes mitochondrial dysfunction and fragmentation. Although VacA targeting of mitochondria has been reported to alter overall cellular metabolism, there is little known about the consequences of extended exposure to the toxin. Here, we describe studies to address this gap in knowledge, which have revealed that mitochondrial dysfunction and fragmentation are followed by a time-dependent recovery of mitochondrial structure, mitochondrial transmembrane potential, and cellular ATP levels. Cells exposed to VacA also initially demonstrated a reduction in oxidative phosphorylation, as well as increase in compensatory aerobic glycolysis. These metabolic alterations were reversed in cells with limited toxin exposure, congruent with the recovery of mitochondrial transmembrane potential and the absence of cytochrome c release from the mitochondria. Taken together, these results are consistent with a model that mitochondrial structure and function are restored in VacA-intoxicated cells.
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Affiliation(s)
- Robin L. Holland
- Department of Pathobiology, College of Veterinary Medicine, University of Illinois Urbana-Champaign, Urbana, Illinois, 61801
| | - Kristopher D. Bosi
- Department of Microbiology, School of Molecular and Cellular Biology, University of Illinois Urbana-Champaign, Urbana, Illinois, 61801
| | - Ami Y. Seeger
- Department of Microbiology, School of Molecular and Cellular Biology, University of Illinois Urbana-Champaign, Urbana, Illinois, 61801
| | - Steven R. Blanke
- Department of Pathobiology, College of Veterinary Medicine, University of Illinois Urbana-Champaign, Urbana, Illinois, 61801
- Department of Microbiology, School of Molecular and Cellular Biology, University of Illinois Urbana-Champaign, Urbana, Illinois, 61801
- Biomedical and Translational Sciences Department, Carle Illinois College of Medicine, University of Illinois, Urbana, Illinois 61801
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Gholamhosseinzadeh E, Ghalehnoei H, Kazemi Veisari A, Sheidaei S, Goli HR. Frequency of significant virulence genes in gastric biopsies of Helicobacter pylori-positive patients with gastritis. AMB Express 2023; 13:67. [PMID: 37410296 DOI: 10.1186/s13568-023-01578-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2023] [Accepted: 06/28/2023] [Indexed: 07/07/2023] Open
Abstract
Helicobacter pylori is one of the most common bacteria affecting human societies worldwide, and is mainly associated with gastrointestinal complications due to different virulence factors. This study aimed to investigate some virulence genes of H. pylori in gastric biopsies of patients with gastritis in Sari city, North of Iran. Informed consent forms were obtained from the studied patients, and those who needed endoscopy were included in the study. To evaluate the prevalence of cagA, iceA1, iceA2, vacA, dupA, and oipA genes, gastric biopsies with positive or negative rapid urease test were collected from 50 patients (25 in each group) with gastro-duodenal diseases. The bacterial DNAs were extracted by a specific kit, and the presence of the genes was analyzed by PCR using specific primers. Eighteen (72%) biopsies from 25 H. pylori-positive samples were cagA-positive, while 17 (68%) biopsies contained the vacA gene, and 11 (44%) samples had both vacA and cagA genes. However, 16 (64%), 12 (48%), 13 (52%), and 14 (56%) biopsies contained dupA, iceA1, iceA2, and oipA genes, respectively. Due to the significant role of the studied virulence factors in the pathogenicity of H. pylori, the high prevalence of these factors in biopsies of patients with gastritis is a concern needing to the management in this region.
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Affiliation(s)
- Ebrahim Gholamhosseinzadeh
- Immunogenetics Research Center, Faculty of Medicine, Mazandaran University of Medical Sciences, Sari, Iran
- Department of Medical Microbiology and Virology, Faculty of Medicine, Mazandaran University of Medical Sciences, Sari, Iran
| | - Hossein Ghalehnoei
- Department of Medical Biotechnology, School of Advanced Technologies in Medicine, Mazandaran University of Medical Sciences, Sari, Iran
| | - Arash Kazemi Veisari
- Gut and Liver Research Center, Non-Communicable Disease Institute, Mazandaran University of Medical Sciences, Sari, Iran
| | - Somayeh Sheidaei
- Department of Pathology, Faculty of Medicine, Mazandaran University of Medical Sciences, Sari, Iran
| | - Hamid Reza Goli
- Immunogenetics Research Center, Faculty of Medicine, Mazandaran University of Medical Sciences, Sari, Iran.
- Department of Medical Microbiology and Virology, Faculty of Medicine, Mazandaran University of Medical Sciences, Sari, Iran.
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Chaturvedi M, Mishra M, Pandey A, Gupta J, Pandey J, Gupta S, Malik MZ, Somvanshi P, Chaturvedi R. Oxidative Products of Curcumin Rather Than Curcumin Bind to Helicobacter Pylori Virulence Factor VacA and Are Required to Inhibit Its Vacuolation Activity. Molecules 2022; 27:molecules27196727. [PMID: 36235264 PMCID: PMC9572645 DOI: 10.3390/molecules27196727] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/13/2022] [Revised: 09/19/2022] [Accepted: 09/23/2022] [Indexed: 11/05/2022]
Abstract
Curcumin is a hydrophobic polyphenol derived from turmeric with potent anti-oxidant, anti-microbial, anti-inflammatory and anti-carcinogenic effects. Curcumin is degraded into various derivatives under in vitro and in vivo conditions, and it appears that its degradation may be responsible for the pharmacological effects of curcumin. The primary risk factor for the cause of gastric cancer is Helicobacter pylori (H. pylori). A virulence factor vacuolating cytotoxic A (VacA) is secreted by H. pylori as a 88 kDa monomer (p88), which can be fragmented into a 33 kDa N-terminal domain (p33) and a 55 kDa C-terminal domain (p55). Recently it has been reported that curcumin oxidation is required to inhibit the activity of another major H.pylori toxin CagA. We performed molecular docking of curcumin and its oxidative derivatives with p33 and p55 domains of VacA. Further, we have examined the effect of the oxidation of curcumin on the vacuolation activity of VacA protein. We observed the binding of curcumin to the p55 domain of VacA at five different sites with moderate binding affinities. Curcumin did not bind to p33 domain of VacA. Remarkably, cyclobutyl cyclopentadione and dihydroxy cyclopentadione, which are oxidized products of curcumin, showed a higher binding affinity with VacA protein at all sites except one as compared to parent curcumin itself. However, cyclobutyl cyclopentadione showed a significant binding affinity for the active site 5 of the p55 protein. Active site five (312-422) of p55 domain of VacA plays a crucial role in VacA-mediated vacuole formation. Invitro experiments showed that curcumin inhibited the vacuolation activity of H. pylori in human gastric cell line AGS cells whereas acetyl and diacetyl curcumin, which cannot be oxidized, failed to inhibit the vacuolation in AGS cells after H. pylori infection. Here our data showed that oxidation is essential for the activity of curcumin in inhibiting the vacuolation activity of H. pylori. Synthesis of these oxidized curcumin derivatives could potentially provide new therapeutic drug molecules for inhibiting H. pylori-mediated pathogenesis.
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Affiliation(s)
- Maya Chaturvedi
- School of Biotechnology, Jawaharlal Nehru University, New Delhi 110067, India
- Department of Energy and Environment, TERI School of Advanced Studies, New Delhi 110067, India
| | - Mohit Mishra
- School of Biotechnology, Jawaharlal Nehru University, New Delhi 110067, India
| | - Achyut Pandey
- School of Biotechnology, Jawaharlal Nehru University, New Delhi 110067, India
| | - Jyoti Gupta
- School of Biotechnology, Jawaharlal Nehru University, New Delhi 110067, India
| | - Jyoti Pandey
- School of Biotechnology, Jawaharlal Nehru University, New Delhi 110067, India
| | - Shilpi Gupta
- School of Biotechnology, Jawaharlal Nehru University, New Delhi 110067, India
| | - Md. Zubbair Malik
- School of Biotechnology, Jawaharlal Nehru University, New Delhi 110067, India
- Department of Genetics and Bioinformatics, Dasman Diabetes Institute, Dasman, P.O. Box 1180, Kuwait City 15462, Kuwait
| | - Pallavi Somvanshi
- School of Computational and Integrative Sciences, Jawaharlal Nehru University, New Delhi 110067, India
- Special Center for System Medicine, Jawaharlal Nehru University, New Delhi 110067, India
| | - Rupesh Chaturvedi
- School of Biotechnology, Jawaharlal Nehru University, New Delhi 110067, India
- Special Center for System Medicine, Jawaharlal Nehru University, New Delhi 110067, India
- Nanofluidiks Pvt. Ltd., Jawaharlal Nehru University-Foundation for Innovation, New Delhi 110067, India
- Correspondence:
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Barzigar R, Haraprasad N, Kumar BYS, Mehran MJ, Fakrudin B. Transient recombinant expression of highly immunogenic CagA, VacA and NapA in Nicotiana benthamiana. Biotechnol Rep (Amst) 2022; 33:e00699. [PMID: 35028298 PMCID: PMC8739878 DOI: 10.1016/j.btre.2021.e00699] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Revised: 12/22/2021] [Accepted: 12/28/2021] [Indexed: 11/26/2022]
Abstract
Interest in the plant-based transient production of recombinant immunogenic antigens has tremendously progressed because plants are cost-effective, easily selectable, free of mammalian contamination, and support complex post-translational modifications. Nicotiana benthamiana is a convenient system for transient expression of recombinant antigens. The present study documented a platform for rapid production of Helicobacter pylori CagA, VacA and NapA antigens three days (first harvest, FH) and six days (second harvest, SH) after agro-infiltration using a syringe. In this study, CagA, VacA and NapA antigen genes from Helicobacter pylori were cloned into the binary vector pBI121 and transformed into Nicotiana benthamiana by the Agrobacterium-mediated process. Leaves of four to five weeks old Nicotiana benthamiana plants were agroinfiltrated with EHA105 subtype of Agrobacterium tumefaciens strain containing cloned CagA (pBI121-CagA), VacA (pBI121-VacA) and NapA (pBI121-NapA) constructs. The transient expression and accumulation of the recombinant genes containing CagA, VacA and NapA expression cassettes were confirmed using qRT-PCR by comparing the relative expression at FH and SH post-infiltration with the non-infiltrated (control) samples and using ELISA at 1/5 and 1/10 dilution ratios. The qRT-PCR findings showed that Agrobacterium-mediated syringe infiltration of leaves of four to five weeks old Nicotiana benthamiana plants produced significantly higher transcript levels of CagA (about 8-fold and 7-fold), VacA (38-fold and 24-fold) and NapA (7-fold and 5-fold) genes at FH and SH compared to the control sample. Besides, the maximum amount of CagA, VacA and NapA antigens were detected at the FH stage compared to the SH stage, when the antibody concentrations of the agro-infiltrated leaf extracts containing these recombinant antigens were diluted in a 1/5 ratio. This study has developed evidence to support that recombinant CagA, VacA and NapA can be transiently produced in Nicotiana benthamiana plants.
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Affiliation(s)
- Rambod Barzigar
- JSS Research Foundation, SJCE Technical Campus, Mysore 570006 India
| | | | - Basaralu Yadurappa Sathish Kumar
- JSS Research Foundation, SJCE Technical Campus, Mysore 570006 India
- Postgraduate Department of Biotechnology, JSS College, Ooty Road, Mysore 570025 India
| | | | - Bashasab Fakrudin
- Department of Biotechnology and Crop Improvement, College of Horticulture, University of Horticulture Sciences Campus, GKVK Post, Bengaluru 560065 India
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Dai J, Zhao J, Mao L, Hu Y, Lv B. Study on the value of antibiotic-resistant gene detection in Helicobacter pylori in China. Exp Ther Med 2022; 23:228. [PMID: 35222705 PMCID: PMC8815056 DOI: 10.3892/etm.2022.11153] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2021] [Accepted: 11/03/2021] [Indexed: 11/05/2022] Open
Abstract
The aim of the present study was to explore the value of detecting antibiotic-resistant genes in Helicobacter pylori (H. pylori) and the association between genotype and antibiotic resistance. Two gastric mucosa samples from each H. pylori-positive patient were collected. Each patient's H. pylori sample was cultured in vitro, and the agar plate dilution method was conducted. In addition, all patient samples were analyzed for the detection of antibiotic resistance-related mutant genes and VacA gene genotypes. The association between VacA genotypes and antibiotic resistance was also determined and the value of mutant gene detection in predicting H. pylori resistance to antibiotics was evaluated. In total, 133 H. pylori-positive patients were enrolled. A total of 22 strains of H. pylori failed to grow in in vitro culture and 25 strains were negative in a H. pylori gene test. Among 108 strains detected by PCR, a total of 39 VacA s1m1 strains, 69 VacA s1m2 strains and no VacA s2 strain were identified. There was no significant association between VacA genotypes and antibiotic resistance. The mutation rates of G616A in the rdxA gene, T87A, G91A, A91G and G91T in the gyrA gene and A2143G and A2142G in the 23S rRNA gene were 32.1, 32.3, 22.6, 12.9, 6.5, 81.8 and 0.0%, respectively. Among these mutant sites, the mutation coincidence rates were as follows, according to the agar plate dilution method: rdxA G616A (81.8%), gyrA G91T (66.7%), gyrA G91A (54.5%), 23 S rRNA A2143G (49.1%), gyrA T87A (45.5%), gyrA A91G (33.3%), penicillin-binding protein 1 (PBP1) C556G (0.0%), PBP1 A562T (0.0%), PBP1 A562G (0.0%) and 16 S rRNA 926-927 (AT-GT) (0.0%). VacA m subtypes were not associated with H. pylori antibiotic resistance. In conclusion, the present findings suggested that the detection of related mutant genes had a clinical application value in predicting the antibiotic resistance of H. pylori, particularly resistance to clarithromycin and levofloxacin.
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Affiliation(s)
- Jinfeng Dai
- Department of Gastroenterology, The First Affiliated Hospital, Zhejiang Chinese Medical University, Hangzhou, Zhejiang 310006, P.R. China
| | - Jing Zhao
- Department of Gastroenterology, The First Affiliated Hospital, Zhejiang Chinese Medical University, Hangzhou, Zhejiang 310006, P.R. China
| | - Liqi Mao
- Department of Gastroenterology, The First Affiliated Hospital, Zhejiang Chinese Medical University, Hangzhou, Zhejiang 310006, P.R. China
| | - Yue Hu
- Department of Gastroenterology, The First Affiliated Hospital, Zhejiang Chinese Medical University, Hangzhou, Zhejiang 310006, P.R. China
| | - Bin Lv
- Department of Gastroenterology, The First Affiliated Hospital, Zhejiang Chinese Medical University, Hangzhou, Zhejiang 310006, P.R. China
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Sharafutdinov I, Knorr J, Soltan Esmaeili D, Backert S, Tegtmeyer N. Cortactin Promotes Effective AGS Cell Scattering by Helicobacter pylori CagA, but Not Cellular Vacuolization and Apoptosis Induced by the Vacuolating Cytotoxin VacA. Pathogens 2021; 11:3. [PMID: 35055951 DOI: 10.3390/pathogens11010003] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Revised: 11/24/2021] [Accepted: 11/25/2021] [Indexed: 12/15/2022] Open
Abstract
Cortactin is an actin-binding protein and actin-nucleation promoting factor regulating cytoskeletal rearrangements in eukaryotes. Helicobacter pylori is a gastric pathogen that exploits cortactin to its own benefit. During infection of gastric epithelial cells, H. pylori hijacks multiple cellular signaling pathways, leading to the disruption of key cell functions. Two bacterial virulence factors play important roles in this scenario, the vacuolating cytotoxin VacA and the translocated effector protein CagA of the cag type IV secretion system (T4SS). Specifically, by overruling the phosphorylation status of cortactin, H. pylori alternates the activity of molecular interaction partners of this important protein, thereby manipulating the performance of cytoskeletal rearrangements, endosomal trafficking and cell movement. Based on shRNA knockdown and other studies, it was previously reported that VacA utilizes cortactin for its cellular uptake, intracellular travel and induction of apoptosis by a mitochondria-dependent mechanism, while CagA induces cell scattering, motility and elongation. To investigate the role of cortactin in these phenotypes in more detail, we produced a complete knockout mutant of cortactin in the gastric adenocarcinoma cell line AGS by CRISPR-Cas9. These cells were infected with H. pylori wild-type or various isogenic mutant strains. Unexpectedly, cortactin deficiency did not prevent the uptake and formation of VacA-dependent vacuoles, nor the induction of apoptosis by internalized VacA, while the induction of T4SS- and CagA-dependent AGS cell movement and elongation were strongly reduced. Thus, we provide evidence that cortactin is required for the function of internalized CagA, but not VacA.
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Cheok YY, Lee CYQ, Cheong HC, Vadivelu J, Looi CY, Abdullah S, Wong WF. An Overview of Helicobacter pylori Survival Tactics in the Hostile Human Stomach Environment. Microorganisms 2021; 9:microorganisms9122502. [PMID: 34946105 PMCID: PMC8705132 DOI: 10.3390/microorganisms9122502] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2021] [Revised: 11/28/2021] [Accepted: 11/29/2021] [Indexed: 12/17/2022] Open
Abstract
Helicobacter pylori is well established as a causative agent for gastritis, peptic ulcer, and gastric cancer. Armed with various inimitable virulence factors, this Gram-negative bacterium is one of few microorganisms that is capable of circumventing the harsh environment of the stomach. The unique spiral structure, flagella, and outer membrane proteins accelerate H. pylori movement within the viscous gastric mucosal layers while facilitating its attachment to the epithelial cells. Furthermore, secretion of urease from H. pylori eases the acidic pH within the stomach, thus creating a niche for bacteria survival and replication. Upon gaining a foothold in the gastric epithelial lining, bacterial protein CagA is injected into host cells through a type IV secretion system (T4SS), which together with VacA, damage the gastric epithelial cells. H. pylori does not only establishes colonization in the stomach, but also manipulates the host immune system to permit long-term persistence. Prolonged H. pylori infection causes chronic inflammation that precedes gastric cancer. The current review provides a brief outlook on H. pylori survival tactics, bacterial-host interaction and their importance in therapeutic intervention as well as vaccine development.
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Affiliation(s)
- Yi Ying Cheok
- Department of Medical Microbiology, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia; (Y.Y.C.); (C.Y.Q.L.); (H.C.C.); (J.V.)
| | - Chalystha Yie Qin Lee
- Department of Medical Microbiology, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia; (Y.Y.C.); (C.Y.Q.L.); (H.C.C.); (J.V.)
| | - Heng Choon Cheong
- Department of Medical Microbiology, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia; (Y.Y.C.); (C.Y.Q.L.); (H.C.C.); (J.V.)
| | - Jamuna Vadivelu
- Department of Medical Microbiology, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia; (Y.Y.C.); (C.Y.Q.L.); (H.C.C.); (J.V.)
| | - Chung Yeng Looi
- School of Biosciences, Faculty of Health & Medical Sciences, Taylor’s University, Subang Jaya 47500, Malaysia;
| | - Suhailah Abdullah
- Department of Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia;
| | - Won Fen Wong
- Department of Medical Microbiology, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia; (Y.Y.C.); (C.Y.Q.L.); (H.C.C.); (J.V.)
- Correspondence:
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11
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MubarakAli D, Akshaya T, Sathya R, Irfan N. Study on the Interaction of Algal Peptides on Virulence Factors of Helicobacter pylori: In Silico Approach. Appl Biochem Biotechnol 2021; 194:37-53. [PMID: 34762267 PMCID: PMC8581125 DOI: 10.1007/s12010-021-03716-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Accepted: 10/08/2021] [Indexed: 11/25/2022]
Abstract
In the Asian region, Helicobacter pylori infects about 80% populations, which is most leading cause of peptic ulcers, and it is an asymptomatic infection. Studies reported that the particular bacteria carry specific virulence factors that leads to severe complications. These virulence factors can be used as a drug targets to inhibit their growth and pathogenicity. Chronic infection with H. pylori virulence factors are CagA, VacA and HtrA positive strains the risk factor of gastric cancer. In this study, we aimed to study the antagonistic interaction pattern between the potential eight algal peptides against the virulence factors of H. pylori through in silico analysis intended to treat peptic ulcer and prevent the further complications such as cancer. The proteins of virulent factors are docked using C-Docker algorithm and calculated the bind energy of the complexes. The results showed that the peptide derived from a green alga, Tetradesmus sp. are active against the three virulent factors such as cag-A, vac-A, and Htr-A with multiple hydrogen, vdW, electrostatic interactions, and mild π-hydrophobic bindings with the libdock energy score for CagA, VacA and HtrA are 175.625, 158.603 and 89.397 kcal/mol. These primes and the peptide lead to develop a better and potential inhibitors against H. pylori infection.
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Affiliation(s)
- Davoodbasha MubarakAli
- School of Life Sciences, B.S. Abdur Rahman Crescent Institute of Science and Technology, Chennai, Tamil Nadu, India.
| | - Thirusangu Akshaya
- School of Life Sciences, B.S. Abdur Rahman Crescent Institute of Science and Technology, Chennai, Tamil Nadu, India
| | - Raghunathan Sathya
- School of Life Sciences, B.S. Abdur Rahman Crescent Institute of Science and Technology, Chennai, Tamil Nadu, India
| | - Navabshan Irfan
- Crescent School of Pharmacy, B.S. Abdur Rahman Crescent Institute of Science and Technology, Chennai, Tamil Nadu, India
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12
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Carlosama-Rosero YH, Acosta-Astaiza CP, Sierra-Torres CH, Bolaños-Bravo HJ. Helicobacter pylori genotypes associated with gastric cancer and dysplasia in Colombian patients. Rev Gastroenterol Mex (Engl Ed) 2021; 87:181-187. [PMID: 34656500 DOI: 10.1016/j.rgmxen.2021.09.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/27/2020] [Accepted: 01/13/2021] [Indexed: 12/17/2022] Open
Abstract
INTRODUCTION AND AIMS Colombia has high incidence levels of gastric cancer that can be explained by the genetic variability of Helicobacter pylori (H. pylori). Our aim was to establish the relation of the H. pylori CagA and VacA genotypes to dysplasia and gastric cancer, in a high-risk population. MATERIAL AND METHODS A case-control study was conducted on 202 patients from a high-risk cancer zone. Patients with dysplasia and gastric cancer (cases) and patients with nonatrophic gastritis (controls) were included. Endoscopic sampling and histologic classification were carried out according to the Sydney system and the Lauren classification. Genetic information was obtained through polymerase chain reaction on paraffin blocks. The measures of association of the variables of interest were evaluated in bivariate and multivariate models. A P<0.05 was considered statistically significant and the SPSS version 25 program was employed. RESULTS Age above 50 years (OR: 23.76; CI: 8.40-67.17; P=0.000) and the VacA s1m1 genotype (OR: 6.18; CI: 1.25-30.51; P=0.025) were associated with higher risk for developing dysplasia and gastric cancer. The CagA+ genotype was not found to be a risk factor for developing those pathologies (OR: 1.02; CI: 0.39-2.62; P=0.965). CONCLUSIONS The H. pylori VacA genotypes are markers for the development of gastric cancer. That information could be used to create a risk index in a predictive model to optimize the healthcare of higher-risk patients.
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Affiliation(s)
- Y H Carlosama-Rosero
- Grupo Interdisciplinario de Investigación en Salud-Enfermedad, Universidad Cooperativa de Colombia, Pasto, Colombia.
| | - C P Acosta-Astaiza
- Grupo de Investigación en Genética Humana y Aplicada, Universidad del Cauca, Popayán, Colombia
| | - C H Sierra-Torres
- Grupo de Investigación en Genética Humana y Aplicada, Universidad del Cauca, Popayán, Colombia
| | - H J Bolaños-Bravo
- Grupo de Investigación en Genética Humana y Aplicada, Universidad del Cauca, Popayán, Colombia
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13
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Ichihara A, Ojima H, Gotoh K, Matsushita O, Take S, Okada H, Watanabe A, Yokota K. Serodiagnosis and Bacterial Genome of Helicobacter pylori Infection. Toxins (Basel) 2021; 13:467. [PMID: 34357939 DOI: 10.3390/toxins13070467] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Revised: 06/18/2021] [Accepted: 06/28/2021] [Indexed: 11/16/2022] Open
Abstract
The infection caused by Helicobacter pylori is associated with several diseases, including gastric cancer. Several methods for the diagnosis of H. pylori infection exist, including endoscopy, the urea breath test, and the fecal antigen test, which is the serum antibody titer test that is often used since it is a simple and highly sensitive test. In this context, this study aims to find the association between different antibody reactivities and the organization of bacterial genomes. Next-generation sequences were performed to determine the genome sequences of four strains of antigens with different reactivity. The search was performed on the common genes, with the homology analysis conducted using a genome ring and dot plot analysis. The two antigens of the highly reactive strains showed a high gene homology, and Western blots for CagA and VacA also showed high expression levels of proteins. In the poorly responsive antigen strains, it was found that the inversion occurred around the vacA gene in the genome. The structure of bacterial genomes might contribute to the poor reactivity exhibited by the antibodies of patients. In the future, an accurate serodiagnosis could be performed by using a strain with few gene mutations of the antigen used for the antibody titer test of H. pylori.
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14
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Chew Y, Chung HY, Lin PY, Wu DC, Huang SK, Kao MC. Outer Membrane Vesicle Production by Helicobacter pylori Represents an Approach for the Delivery of Virulence Factors CagA, VacA and UreA into Human Gastric Adenocarcinoma (AGS) Cells. Int J Mol Sci 2021; 22:3942. [PMID: 33920443 DOI: 10.3390/ijms22083942] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2021] [Revised: 04/07/2021] [Accepted: 04/09/2021] [Indexed: 01/18/2023] Open
Abstract
Helicobacter pylori infection is the etiology of several gastric-related diseases including gastric cancer. Cytotoxin associated gene A (CagA), vacuolating cytotoxin A (VacA) and α-subunit of urease (UreA) are three major virulence factors of H. pylori, and each of them has a distinct entry pathway and pathogenic mechanism during bacterial infection. H. pylori can shed outer membrane vesicles (OMVs). Therefore, it would be interesting to explore the production kinetics of H. pylori OMVs and its connection with the entry of key virulence factors into host cells. Here, we isolated OMVs from H. pylori 26,695 strain and characterized their properties and interaction kinetics with human gastric adenocarcinoma (AGS) cells. We found that the generation of OMVs and the presence of CagA, VacA and UreA in OMVs were a lasting event throughout different phases of bacterial growth. H. pylori OMVs entered AGS cells mainly through macropinocytosis/phagocytosis. Furthermore, CagA, VacA and UreA could enter AGS cells via OMVs and the treatment with H. pylori OMVs would cause cell death. Comparison of H. pylori 26,695 and clinical strains suggested that the production and characteristics of OMVs are not only limited to laboratory strains commonly in use, but a general phenomenon to most H. pylori strains.
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15
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Carlosama-Rosero YH, Acosta-Astaiza CP, Sierra-Torres CH, Bolaños-Bravo HJ. Helicobacter pylori genotypes associated with gastric cancer and dysplasia in Colombian patients. Rev Gastroenterol Mex (Engl Ed) 2021; 87:S0375-0906(21)00031-8. [PMID: 33789817 DOI: 10.1016/j.rgmx.2021.01.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2020] [Revised: 12/10/2020] [Accepted: 01/13/2021] [Indexed: 01/07/2023]
Abstract
INTRODUCTION AND AIMS Colombia has high incidence levels of gastric cancer that can be explained by the genetic variability of Helicobacter pylori (H. pylori). Our aim was to establish the relation of the H. pylori CagA and VacA genotypes to dysplasia and gastric cancer, in a high-risk population. MATERIAL AND METHODS A case-control study was conducted on 202 patients from a high-risk cancer zone. Patients with dysplasia and gastric cancer (cases) and patients with nonatrophic gastritis (controls) were included. Endoscopic sampling and histologic classification were carried out according to the Sydney system and the Lauren classification. Genetic information was obtained through polymerase chain reaction on paraffin blocks. The measures of association of the variables of interest were evaluated in bivariate and multivariate models. A P<0.05 was considered statistically significant and the SPSS version 25 program was employed. RESULTS Age above 50 years (OR: 23.76; CI: 8.40-67.17; P=0.000) and the VacA s1m1 genotype (OR: 6.18; CI: 1.25-30.51; P=0.025) were associated with higher risk for developing dysplasia and gastric cancer. The CagA+ genotype was not found to be a risk factor for developing those pathologies (OR: 1.02; CI: 0.39-2.62; P=0.965). CONCLUSIONS The H. pylori VacA genotypes are markers for the development of gastric cancer. That information could be used to create a risk index in a predictive model to optimize the healthcare of higher-risk patients.
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Affiliation(s)
- Y H Carlosama-Rosero
- Grupo Interdisciplinario de Investigación en Salud-Enfermedad, Universidad Cooperativa de Colombia, Pasto, Colombia.
| | - C P Acosta-Astaiza
- Grupo de Investigación en Genética Humana y Aplicada, Universidad del Cauca, Popayán, Colombia
| | - C H Sierra-Torres
- Grupo de Investigación en Genética Humana y Aplicada, Universidad del Cauca, Popayán, Colombia
| | - H J Bolaños-Bravo
- Grupo de Investigación en Genética Humana y Aplicada, Universidad del Cauca, Popayán, Colombia
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16
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Segawa T, Ohno Y, Tsuchida S, Ushida K, Yoshioka M. Helicobacter delphinicola sp. nov., isolated from common bottlenose dolphins Tursiops truncatus with gastric diseases. Dis Aquat Organ 2020; 141:157-169. [PMID: 33030444 DOI: 10.3354/dao03511] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Gastritis and gastric ulcers are well-recognized symptoms in cetaceans, and the genus Helicobacter is considered as the main cause. In this study, we examined the gastric fluid of captive common bottlenose dolphins Tursiops truncatus with gastric diseases in order to isolate the organisms responsible for diagnosis and treatment. Four Gram-negative, rod-shaped isolates (TSBT, TSH1, TSZ, and TSH3) with tightly coiled spirals with 2-4 turns and 2-6 bipolar, sheathed flagella, were obtained from gastric fluids of common bottlenose dolphins with gastric diseases. Phylogenetic analysis, based on 16S rRNA, atpA, and 60 kDa heat-shock protein (hsp60) genes, demonstrated that these isolates form a novel lineage within the genus Helicobacter. Analyses of 16S rRNA, atpA, and hsp60 gene sequences showed that isolate TSBT was most closely related to H. cetorum MIT99-5656T (98.5% similarity), H. pylori ATCC 43504T (76.7% similarity), and H. pylori ATCC 43504T (78.0% similarity), respectively. Type strains of Helicobacter showing resistance to 2% NaCl have not been reported previously; however, these novel isolates were resistant to 2% NaCl. Culture supernatant of some isolates induced intracellular vacuolization in mammalian cultured cells. These data, together with the different morphological and biochemical characteristics of the isolates, reveal that these isolates represent a novel species for which we propose the name Helicobacter delphinicola sp. nov. with type strain TSBT (= JCM 32789T = TSD-183T). Future studies will confirm whether H. delphinicola plays a role in lesion etiopathogenesis in cetaceans.
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Affiliation(s)
- Takao Segawa
- Cetacean Research Center, Graduate School of Bioresources, Mie University, 1577 Kurimamachiya, Tsu, Mie 514-8507, Japan
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17
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Abstract
The original strategies developed by Helicobacter pylori to persistently colonise its host and to deregulate its cellular functions make this bacterium an outstanding model to study host-pathogen interaction and the mechanisms responsible for bacterial-induced carcinogenesis. During the last year, significant results were obtained on the role of bacterial factors essential for gastric colonisation such as spiral shape maintenance, orientation through chemotaxis and the formation of bacteria clonal population islands inside the gastric glands. Particularities of the H pylori cell surface, a structure important for immune escape, were demonstrated. New insights in the bacterial stress response revealed the importance of DNA methylation-mediated regulation. Further findings were reported on H pylori components that mediate natural transformation and mechanisms of bacterial DNA horizontal transfer which maintain a high level of H pylori genetic variability. Within-host evolution was found to be niche-specific and probably associated with physiological differences between the antral and oxyntic gastric mucosa. In addition, with the progress of CryoEM, high-resolution structures of the major virulence factors, VacA and CagT4SS, were obtained. The use of gastric organoid models fostered research revealing, preferential accumulation of bacteria at the site of injury during infection. Several studies further characterised the role of CagA in the oncogenic properties of H pylori, identifying the activation of novel CagA-dependent pathways, leading to the promotion of genetic instabilities, epithelial-to-mesenchymal transition and finally carcinogenesis. Recent studies also highlight that microRNA-mediated regulation and epigenetic modifications, through DNA methylation, are key events in the H pylori-induced tumorigenesis process.
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Affiliation(s)
- Milica Denic
- Département de Microbiologie, Institut Pasteur, UMR CNRS 2001, Unité Pathogenèse de Helicobacter, Paris, France.,Sorbonne Paris Cité, Cellule Pasteur, Université Paris Diderot, Paris, France
| | - Eliette Touati
- Département de Microbiologie, Institut Pasteur, UMR CNRS 2001, Unité Pathogenèse de Helicobacter, Paris, France
| | - Hilde De Reuse
- Département de Microbiologie, Institut Pasteur, UMR CNRS 2001, Unité Pathogenèse de Helicobacter, Paris, France
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18
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Jarzab M, Posselt G, Meisner-Kober N, Wessler S. Helicobacter pylori-Derived Outer Membrane Vesicles (OMVs): Role in Bacterial Pathogenesis? Microorganisms 2020; 8:E1328. [PMID: 32878302 DOI: 10.3390/microorganisms8091328] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Revised: 08/24/2020] [Accepted: 08/31/2020] [Indexed: 01/06/2023] Open
Abstract
Persistent infections with the human pathogen Helicobacter pylori (H. pylori) have been closely associated with the induction and progression of a wide range of gastric disorders, including acute and chronic gastritis, ulceration in the stomach and duodenum, mucosa-associated lymphoid tissue (MALT) lymphoma, and gastric adenocarcinoma. The pathogenesis of H. pylori is determined by a complicated network of manifold mechanisms of pathogen–host interactions, which involves a coordinated interplay of H. pylori pathogenicity and virulence factors with host cells. While these molecular and cellular mechanisms have been intensively investigated to date, the knowledge about outer membrane vesicles (OMVs) derived from H. pylori and their implication in bacterial pathogenesis is not well developed. In this review, we summarize the current knowledge on H. pylori-derived OMVs.
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19
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Abstract
Introduction Helicobacter pylori causes, via the influence of several virulence factors, persistent infection of the stomach, which leads to severe complications. Vacuolating cytotoxin A (VacA) is observed in almost all clinical strains of H. pylori; however, only some strains produce the toxigenic and pathogenic VacA, which is influenced by the gene sequence variations. VacA exerts its action by causing cell vacuolation and apoptosis. We performed a PubMed search to review the latest literatures published in English language. Areas covered Articles regarding H. pylori VacA and its genotypes, architecture, internalization, and role in gastric infection and pathogenicity are reviewed. We included the search for recently published literature until January 2020. Expert opinion H. pylori VacA plays a crucial role in severe gastric pathogenicity. In addition, VacA mediated in vivo bacterial survival leads to persistent infection and an enhanced bacterial evasion from the action of antibiotics and the innate host defense system, which leads to drug evasion. VacA as a co-stimulator for the CagA phosphorylation may exert a synergistic effect playing an important role in the CagA-mediated pathogenicity.
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Affiliation(s)
- Shamshul Ansari
- Department of Microbiology, Chitwan Medical College , Bharatpur, Nepal
| | - Yoshio Yamaoka
- Department of Environmental and Preventive Medicine, Oita University Faculty of Medicine , Yufu, Oita, Japan.,Global Oita Medical Advanced Research Center for Health , Yufu, Oita, Japan.,Department of Medicine, Gastroenterology and Hepatology Section, Baylor College of Medicine , Houston, TX, USA.,Borneo Medical and Health Research Centre, Universiti Malaysia Sabah , Kota Kinabaru, Malaysia
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20
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Sukri A, Hanafiah A, Mohamad Zin N, Kosai NR. Epidemiology and role of Helicobacter pylori virulence factors in gastric cancer carcinogenesis. APMIS 2020; 128:150-161. [PMID: 32352605 DOI: 10.1111/apm.13034] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Accepted: 02/09/2020] [Indexed: 02/06/2023]
Abstract
Infection with Helicobacter pylori is associated with the development of gastric cancer. Although the prevalence of gastric cancer has declined throughout years due to improvement in early screening strategy, mortality due to gastric cancer has not changed. Incidence and mortality due to gastric cancer are higher in developing countries as compared to developed countries. Diagnosis and prognosis of gastric cancer are still poor with patients usually diagnosed with cancer at an advanced stage. Eradication of H. pylori is pertinent for the prevention of gastric cancer. However, the rise in antimicrobial resistance among H. pylori isolates has complicated the prevention strategy. H. pylori express multiple virulence factors for survival in the hostile acid gastric environment. The expression of oncogenic protein cytotoxin-associated gene A (CagA), vacuolating cytotoxin A (VacA), and outer inflammatory protein is essential for H. pylori to exert pathogenesis towards the host. Interestingly, <3% of H. pylori-infected subjects develop gastric cancer, suggesting a unique way of interaction between the host's immune response and H. pylori virulence factors. This article is aimed to review the epidemiology and role of H. pylori in gastric carcinogenesis. A better understanding of the interaction between H. pylori virulence factors and host is required for better gastric cancer prevention.
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Affiliation(s)
- Asif Sukri
- Programme of Biomedical Science, Faculty of Health Science, Universiti Kebangsaan Malaysia, Kuala Lumpur, Malaysia
| | - Alfizah Hanafiah
- Department of Medical Microbiology and Immunology, Faculty of Medicine, Universiti Kebangsaan Malaysia, Kuala Lumpur, Malaysia
| | - Noraziah Mohamad Zin
- Programme of Biomedical Science, Faculty of Health Science, Universiti Kebangsaan Malaysia, Kuala Lumpur, Malaysia
| | - Nik Ritza Kosai
- Department of Surgery, Faculty of Medicine, Universiti Kebangsaan Malaysia, Kuala Lumpur, Malaysia
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21
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Seeger AY, Ringling MD, Zohair H, Blanke SR. Risk factors associated with gastric malignancy during chronic Helicobacter pylori Infection. Med Res Arch 2020; 8:2068. [PMID: 37655156 PMCID: PMC10470974 DOI: 10.18103/mra.v8i3.2068] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/02/2023]
Abstract
Chronic Helicobacter pylori (Hp) infection is considered to be the single most important risk factor for the development of gastric adenocarcinoma in humans, which is a leading cause of cancer-related death worldwide. Nonetheless, Hp infection does not always progress to malignancy, and, gastric adenocarcinoma can occur in the absence of detectable Hp carriage, highlighting the complex and multifactorial nature of gastric cancer. Here we review known contributors to gastric malignancy, including Hp virulence factors, host genetic variation, and multiple environmental variables. In addition, we assess emerging evidence that resident gastric microflora in humans might impact disease progression in Hp-infected individuals. Molecular approaches for microbe identification have revealed differences in the gastric microbiota composition between cancer and non-cancerous patients, as well as infected and uninfected individuals. Although the reasons underlying differences in microbial community structures are not entirely understood, gastric atrophy and hypochlorhydria that accompany chronic Hp infection may be a critical driver of gastric dysbiosis that promote colonization of microbes that contribute to increased risk of malignancy. Defining the importance and role of the gastric microbiota as a potential risk factor for Hp-associated gastric cancer is a vital and exciting area of current research.
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Affiliation(s)
- Ami Y. Seeger
- Department of Microbiology, School of Molecular and Cellular Biology, College of Liberal Arts and Sciences, University of Illinois Urbana-Champaign, Urbana, Illinois, 61801
| | - Megan D. Ringling
- Department of Microbiology, School of Molecular and Cellular Biology, College of Liberal Arts and Sciences, University of Illinois Urbana-Champaign, Urbana, Illinois, 61801
| | - Huzaifa Zohair
- Department of Microbiology, School of Molecular and Cellular Biology, College of Liberal Arts and Sciences, University of Illinois Urbana-Champaign, Urbana, Illinois, 61801
| | - Steven R. Blanke
- Department of Microbiology, School of Molecular and Cellular Biology, College of Liberal Arts and Sciences, University of Illinois Urbana-Champaign, Urbana, Illinois, 61801
- Department of Pathobiology, College of Veterinary Medicine, University of Illinois Urbana-Champaign, Urbana, Illinois, 61801
- Biomedical and Translational Sciences Department, Carle Illinois College of Medicine, University of Illinois Urbana-Champaign, Urbana, Illinois, 61801
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22
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Hanafiah A, Lopes BS. Genetic diversity and virulence characteristics of Helicobacter pylori isolates in different human ethnic groups. Infect Genet Evol 2019; 78:104135. [PMID: 31837482 DOI: 10.1016/j.meegid.2019.104135] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2019] [Revised: 12/03/2019] [Accepted: 12/06/2019] [Indexed: 02/07/2023]
Abstract
Helicobacter pylori is the most predominant bacterium in almost 50% of the world's population and colonization causes a persistent inflammatory response leading to chronic gastritis. It shows high genetic diversity and individuals generally harbour a distinct bacterial population. With the advancement of whole-genome sequencing technology, new H. pylori subpopulations have been identified that show admixture between various H. pylori strains. Genotypic variation of H. pylori may be related to the presence of virulence factors among strains and is associated with different outcomes of infection in different individuals. This review summarizes the genetic diversity in H. pylori strain populations and its virulence characteristics responsible for variable outcomes in different ethnic groups.
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Affiliation(s)
- Alfizah Hanafiah
- Department of Medical Microbiology & Immunology, Faculty of Medicine, Universiti Kebangsaan Malaysia, 56000 Cheras, Kuala Lumpur, Malaysia.
| | - Bruno S Lopes
- Department of Medical Microbiology, School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, 0:025 Polwarth Building, Aberdeen AB25 2ZD, United Kingdom.
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23
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Sgouras D, Tegtmeyer N, Wessler S. Activity and Functional Importance of Helicobacter pylori Virulence Factors. Adv Exp Med Biol 2019; 1149:35-56. [PMID: 31016624 DOI: 10.1007/5584_2019_358] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Helicobacter pylori is a very successful Gram-negative pathogen colonizing the stomach of humans worldwide. Infections with this bacterium can generate pathologies ranging from chronic gastritis and peptic ulceration to gastric cancer. The best characterized H. pylori virulence factors that cause direct cell damage include an effector protein encoded by the cytotoxin-associated gene A (CagA), a type IV secretion system (T4SS) encoded in the cag-pathogenicity island (cag PAI), vacuolating cytotoxin A (VacA), γ-glutamyl transpeptidase (GGT), high temperature requirement A (HtrA, a serine protease) and cholesterol glycosyl-transferase (CGT). Since these H. pylori factors are either surface-exposed, secreted or translocated, they can directly interact with host cell molecules and are able to hijack cellular functions. Studies on these bacterial factors have progressed substantially in recent years. Here, we review the current status in the characterization of signaling cascades by these factors in vivo and in vitro, which comprise the disruption of cell-to-cell junctions, induction of membrane rearrangements, cytoskeletal dynamics, proliferative, pro-inflammatory, as well as, pro-apoptotic and anti-apoptotic responses or immune evasion. The impact of these signal transduction modules in the pathogenesis of H. pylori infections is discussed.
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24
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Capurro MI, Prashar A, Jones NL. MCOLN1/TRPML1 inhibition - a novel strategy used by Helicobacter pylori to escape autophagic killing and antibiotic eradication therapy in vivo. Autophagy 2019; 16:169-170. [PMID: 31599196 DOI: 10.1080/15548627.2019.1677322] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
Abstract
Inhibition of host macroautophagy/autophagy is one of the strategies used by several intracellular pathogens, including H. pylori, to escape killing. Here we discuss our recent work that revealed the novel mechanism by which the vacuolating cytotoxin A (VacA) produced by H. pylori inhibits lysosomal and autophagic killing. We discovered that VacA impairs the activity of the lysosomal calcium channel MCOLN1/TRPML1 leading to the formation of enlarged, dysfunctional lysosomes and autophagosomes that serve as an intracellular niche, which allows the bacteria to escape eradication therapy.
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Affiliation(s)
| | | | - Nicola L Jones
- Cell Biology Program.,Division of Gastroenterology, Hepatology and Nutrition, The Hospital for Sick Children, Toronto, ON, Canada.,Department of Paediatrics and Physiology, University of Toronto, Toronto, ON, Canada
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25
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Knorr J, Ricci V, Hatakeyama M, Backert S. Classification of Helicobacter pylori Virulence Factors: Is CagA a Toxin or Not? Trends Microbiol 2019; 27:731-8. [DOI: 10.1016/j.tim.2019.04.010] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2019] [Revised: 04/16/2019] [Accepted: 04/26/2019] [Indexed: 12/20/2022]
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26
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Abstract
In this review, we shall focus on the last year progression understanding the pathogenesis of Helicobacter pylori infection in the light of recent data related to adaptation of H pylori to the harsh acidic environment in the stomach, colonization of gastric mucosa via interaction with mucin 5 (MUC5AC) and other host cell receptors, the ability to form biofilm, interference with the host metabolic pathways, and induction of neuroimmune cross-talk as well as downregulation of gastric barrier homeostasis and its consequences for the disease development. The role of the membrane vesicles of these bacteria has been emphasized as an important source of virulence factors. Furthermore, we shall describe molecular and functional studies on new aspects of VacA and CagA virulence, including the role of urease in the upregulation of VacA toxicity, an epithelial-mesenchymal transition mediated by CagA, and the role of interaction of HopQ adhesin with carcinoembryonic antigen-related cell adhesion molecules (CEACAMs) in CagA translocation into the host cells by the type IV secretion system (T4SS). The role of molecular mimicry between a common sequence (ATVLA) of H pylori heat shock protein (Hsp) B and human Hsp60 in the induction of potentially autoreactive antibodies is discussed. All these new data illustrate further progress in understanding H pylori pathogenicity and facilitate the search for new therapeutic targets as well as development of immunoprophylaxis methods based on new chimeric UreB and HpA proteins.
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Affiliation(s)
- Magdalena Chmiela
- Laboratory of GastroimmunologyDepartment of Immunology and Infectious BiologyInstitute of Microbiology, Biotechnology and ImmunologyFaculty of Biology and Environmental ProtectionUniversity of ŁódźŁódźPoland
| | - Juozas Kupcinskas
- Institute for Digestive ResearchAcademy of MedicineLithuanian University of Health SciencesKaunasLithuania,Department of GastroenterologyAcademy of MedicineLithuanian University of Health ScienceKaunasLithuania
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27
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Guo L, Hong D, Wang S, Zhang F, Tang F, Wu T, Chu Y, Liu H, He M, Yang H, Yin R, Liu K. Therapeutic Protection Against H. pylori Infection in Mongolian Gerbils by Oral Immunization With a Tetravalent Epitope-Based Vaccine With Polysaccharide Adjuvant. Front Immunol 2019; 10:1185. [PMID: 31191547 PMCID: PMC6546824 DOI: 10.3389/fimmu.2019.01185] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2018] [Accepted: 05/09/2019] [Indexed: 12/28/2022] Open
Abstract
Urease is an effective target for design of a therapeutic epitope vaccine against Helicobacter pylori (H. pylori). In our previous studies, an epitope vaccine CTB-UE containing Th and B epitopes from H. pylori urease was constructed, and the CTB-UE vaccine could provide therapeutic effect on H. pylori infection in mice. However, a multivalent vaccine, combining different antigens participating in different aspects of H. pylori colonization and pathogenesis, may be more effective as a therapeutic vaccine than a univalent vaccine targetting urease. Therefore, a multivalent epitope vaccine FVpE, containing Th1-type immune adjuvant NAP, three selected functional fragments from CagA and VacA, and an urease multi-epitope peptide (UE) from CTB-UE, was constructed in this study and expected to obtain better sterilizing immunity than the univalent epitope vaccine CTB-UE. The therapeutic effect of multivalent epitope vaccine FVpE with polysaccharide adjuvant (PA) was evaluated in H. pylori-infected Mongolian gerbil model. The results showed that both FvpE and CTB-UE vaccine could induce similar levels of specific antibodies against H. pylori urease, and had similar inhibition effect on H. pylori urease activity. However, only FVpE could induce high levels of specific antibodies to CagA, VacA, and NAP. In addition, oral therapeutic immunization with FVpE plus PA significantly reduced the number of H. pylori colonies in the stomach of Mongolian gerbils compared with oral immunization with CTB-UE plus PA, or FVpE only, and the FVpE vaccine with PA even exhibited sterilizing immunity. The protection of FVpE was related to the mixed CD4+ T cell responses and epitope-specific antibodies against various H. pylori antigens. These results indicate that a multivalent epitope vaccine targetting various H. pylori antigens could be a promising candidate against H. pylori infection.
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Affiliation(s)
- Le Guo
- Ningxia Key Laboratory of Clinical and Pathogenic Microbiology, General Hospital of Ningxia Medical University, Yinchuan, China.,Ningxia Key Laboratory of Cerebrocranial Diseases, Ningxia Medical University, Yinchuan, China.,Department of Medical Laboratory, School of Clinical Medicine, Ningxia Medical University, Yinchuan, China
| | - Dantong Hong
- Department of Medical Laboratory, School of Clinical Medicine, Ningxia Medical University, Yinchuan, China
| | - Shue Wang
- Department of Medical Laboratory, School of Clinical Medicine, Ningxia Medical University, Yinchuan, China
| | - Fan Zhang
- Department of Medical Laboratory, School of Clinical Medicine, Ningxia Medical University, Yinchuan, China
| | - Feng Tang
- Research Center for High Altitude Medicine, Qinghai University, Xining, China
| | - Tao Wu
- Clinical Laboratory, People's Hospital of Ningxia Hui Autonomous Region, Yinchuan, China
| | - Yuankui Chu
- Department of Medical Laboratory, School of Clinical Medicine, Ningxia Medical University, Yinchuan, China
| | - Hongpeng Liu
- Department of Medical Laboratory, School of Clinical Medicine, Ningxia Medical University, Yinchuan, China
| | - Meng He
- Department of Medical Laboratory, School of Clinical Medicine, Ningxia Medical University, Yinchuan, China
| | - Hua Yang
- Department of Medical Laboratory, School of Clinical Medicine, Ningxia Medical University, Yinchuan, China
| | - Runting Yin
- Center for Cell Therapy, Affiliated Hospital of Jiangsu University, Zhenjiang, China
| | - Kunmei Liu
- Ningxia Key Laboratory of Cerebrocranial Diseases, Ningxia Medical University, Yinchuan, China.,Department of Medical Laboratory, School of Clinical Medicine, Ningxia Medical University, Yinchuan, China
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28
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Tserentogtokh T, Gantuya B, Subsomwong P, Oyuntsetseg K, Bolor D, Erdene-Ochir Y, Azzaya D, Davaadorj D, Uchida T, Matsuhisa T, Yamaoka Y. Western-Type Helicobacter pylori CagA are the Most Frequent Type in Mongolian Patients. Cancers (Basel) 2019; 11:cancers11050725. [PMID: 31137742 PMCID: PMC6562502 DOI: 10.3390/cancers11050725] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2019] [Revised: 04/27/2019] [Accepted: 05/22/2019] [Indexed: 12/21/2022] Open
Abstract
Helicobacter pylori infection possessing East-Asian-type CagA is associated with carcinogenesis. Mongolia has the highest mortality rate from gastric cancer. Therefore, we evaluated the CagA status in the Mongolian population. High risk and gastric cancer patients were determined using endoscopy and histological examination. H. pylori strains were isolated from different locations in Mongolia. The CagA subtypes (East-Asian-type or Western-type, based on sequencing of Glu-Pro-Ile-Tyr-Ala (EPIYA) segments) and vacA genotypes (s and m regions) were determined using PCR-based sequencing and PCR, respectively. In total, 368 patients were examined (341 gastritis, 10 peptic ulcer, and 17 gastric cancer). Sixty-two (16.8%) strains were cagA-negative and 306 (83.1%) were cagA-positive (293 Western-type, 12 East-Asian-type, and one hybrid type). All cagA-negative strains were isolated from gastritis patients. In the gastritis group, 78.6% (268/341) had Western-type CagA, 2.9% (10/341) had East-Asian-type, and 18.2% (61/341) were cagA-negative. However, all H. pylori from gastric cancer patients possessed Western-type CagA. Histological analyses showed that East-Asian-type CagA was the most virulent strains, followed by Western-type and cagA-negative strains. This finding agreed with the current consensus. CagA-positive strains were the most virulent type. However, the fact that different CagA types can explain the high incidence of gastric cancer might be inapplicable in Mongolia.
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Affiliation(s)
- Tegshee Tserentogtokh
- Department of Gastroenterology, Mongolian National University of Medical Sciences, Ulaanbaatar city 14210, Mongolia.
- Department of Endoscopy, Medipas hospital, Orkhon province, Bayan-Undur soum, Zest bag 61029 , Mongolia.
| | - Boldbaatar Gantuya
- Department of Gastroenterology, Mongolian National University of Medical Sciences, Ulaanbaatar city 14210, Mongolia.
- Department of Environmental and Preventive Medicine, Oita University Faculty of Medicine, Yufu city 879-5593, Japan.
| | - Phawinee Subsomwong
- Department of Environmental and Preventive Medicine, Oita University Faculty of Medicine, Yufu city 879-5593, Japan.
| | - Khasag Oyuntsetseg
- Department of Gastroenterology, Mongolian National University of Medical Sciences, Ulaanbaatar city 14210, Mongolia.
| | - Dashdorj Bolor
- Department of Endoscopy, National Cancer Center, Ulaanbaatar city 13370, Mongolia.
| | - Yansan Erdene-Ochir
- Department of General Surgery National Cancer Center, Ulaanbaatar city 13370, Mongolia.
| | - Dashdorj Azzaya
- Department of Environmental and Preventive Medicine, Oita University Faculty of Medicine, Yufu city 879-5593, Japan.
| | - Duger Davaadorj
- Department of Gastroenterology, Mongolian National University of Medical Sciences, Ulaanbaatar city 14210, Mongolia.
| | - Tomohisa Uchida
- Department of Molecular Pathology, Oita University Faculty of Medicine, Yufu city 879-5593, Japan.
| | - Takeshi Matsuhisa
- Department of Endoscopy, Nippon Medical University Tama Nagayama Hospital, Tokyo 113-8602, Japan.
| | - Yoshio Yamaoka
- Department of Environmental and Preventive Medicine, Oita University Faculty of Medicine, Yufu city 879-5593, Japan.
- Global Oita Medical Advanced Research Center for Health, Yufu city 879-5593, Japan.
- Department of Medicine, Gastroenterology and Hepatology section, Baylor College of Medicine, Houston, TX 77030, USA.
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29
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Gutiérrez-Escobar AJ, Bravo MM, Acevedo O, Backert S. Molecular evolution of the VacA p55 binding domain of Helicobacter pylori in mestizos from a high gastric cancer region of Colombia. PeerJ 2019; 7:e6634. [PMID: 31119065 PMCID: PMC6507892 DOI: 10.7717/peerj.6634] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2018] [Accepted: 02/18/2019] [Indexed: 11/20/2022] Open
Abstract
The stomach bacterium Helicobacter pylori is one of the most prevalent pathogens in humans, closely linked with serious diseases such as gastric cancer. The microbe has been associated with its host for more than 100,000 years and escorted modern humans out of Africa. H. pylori is predominantly transmitted within families and dispersed globally, resulting in distinct phylogeographic patterns, which can be utilized to investigate migrations and bioturbation events in human history. Latin America was affected by several human migratory waves due to the Spanish colonisation that drastically changed the genetic load and composition of the bacteria and its host. Genetic evidence indicates that independent evolutionary lines of H. pylori have evolved in mestizos from Colombia and other countries in the region during more than 500 years since colonisation. The vacuolating cytotoxin VacA represents a major virulence factor of the pathogen comprising two domains, p33 and p55, the latter of which is essential for binding to the host epithelial cell. The evolution of the VacA toxin in Colombia has been strongly biased due to the effects of Spanish colonization. However, the variation patterns and microevolution of the p55 domain have not yet been described for this population. In the present study, we determined the genetic polymorphisms and deviations in the neutral model of molecular evolution in the p55 domain of 101 clinical H. pylori isolates collected in Bogotá, a city located in Andean mountains characterized by its high gastric cancer risk and its dominant mestizo population. The microevolutionary patterns of the p55 domain were shaped by recombination, purifying and episodic diversifying positive selection. Furthermore, amino acid positions 261 and 321 in the p55 domain of VacA show a high variability among mestizos clinical subsets, suggesting that natural selection in H. pylori may operate differentially in patients with different gastric diseases.
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Affiliation(s)
- Andrés J. Gutiérrez-Escobar
- Universidad de Ciencias Aplicadas y Ambientales U.D.C.A. Doctorado en Ciencias Biológicas, Pontificia Universidad Javeriana., Bogotá, Colombia
- Division of Microbiology, Department of Biology, Friedrich Alexander University Erlangen/Nuremberg, Erlangen, Germany
| | - María M. Bravo
- Grupo de Investigación en Biología del Cáncer, Instituto Nacional de Cancerología, Bogotá, Colombia
| | - Orlando Acevedo
- Grupo de Biofísica y Bioquímica Estructural, Facultad de Ciencias, Pontifica Universidad Javeriana, Bogotá, Colombia
| | - Steffen Backert
- Division of Microbiology, Department of Biology, Friedrich Alexander University Erlangen/Nuremberg, Erlangen, Germany
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30
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Caston RR, Loh JT, Voss BJ, McDonald WH, Scholz MB, McClain MS, Cover TL. Effect of environmental salt concentration on the Helicobacter pylori exoproteome. J Proteomics 2019; 202:103374. [PMID: 31063819 DOI: 10.1016/j.jprot.2019.05.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2019] [Revised: 04/20/2019] [Accepted: 05/02/2019] [Indexed: 02/07/2023]
Abstract
Helicobacter pylori infection and a high salt diet are each risk factors for gastric cancer. In this study, we tested the hypothesis that environmental salt concentration influences the composition of the H. pylori exoproteome. H. pylori was cultured in media containing varying concentrations of sodium chloride, and aliquots were fractionated and analyzed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). We identified proteins that were selectively released into the extracellular space, and we identified selectively released proteins that were differentially abundant in culture supernatants, depending on the environmental salt concentration. We also used RNA-seq analysis to identify genes that were differentially expressed in response to environmental salt concentration. The salt-responsive proteins identified by proteomic analysis and salt-responsive genes identified by RNA-seq analysis were mostly non-concordant, but the secreted toxin VacA was salt-responsive in both analyses. Western blot analysis confirmed that VacA levels in the culture supernatant were increased in response to high salt conditions, and quantitative RT-qPCR experiments confirmed that vacA transcription was upregulated in response to high salt conditions. These results indicate that environmental salt concentration influences the composition of the H. pylori exoproteome, which could contribute to the increased risk of gastric cancer associated with a high salt diet. SIGNIFICANCE: Helicobacter pylori-induced alterations in the gastric mucosa have been attributed, at least in part, to the actions of secreted H. pylori proteins. In this study, we show that H. pylori growth in high salt concentrations leads to increased levels of a secreted VacA toxin. Salt-induced alterations in the composition of the H. pylori exoproteome is relevant to the increased risk of gastric cancer associated with consumption of a high salt diet.
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Affiliation(s)
- Rhonda R Caston
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - John T Loh
- Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Bradley J Voss
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - W Hayes McDonald
- Proteomics Laboratory, Mass Spectrometry Research Center, Vanderbilt University School of Medicine, Nashville, TN, USA; Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Matthew B Scholz
- Vanderbilt Technologies for Advanced Genetics (VANTAGE), Vanderbilt University Medical Center, Nashville, TN, USA
| | - Mark S McClain
- Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Timothy L Cover
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, TN, USA; Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN, USA; Veterans Affairs Tennessee Valley Healthcare System, Nashville, TN, USA.
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31
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Foegeding NJ, Raghunathan K, Campbell AM, Kim SW, Lau KS, Kenworthy AK, Cover TL, Ohi MD. Intracellular Degradation of Helicobacter pylori VacA Toxin as a Determinant of Gastric Epithelial Cell Viability. Infect Immun 2019; 87:e00783-18. [PMID: 30692181 DOI: 10.1128/IAI.00783-18] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2018] [Accepted: 01/23/2019] [Indexed: 12/19/2022] Open
Abstract
Helicobacter pylori VacA is a secreted pore-forming toxin that induces cell vacuolation in vitro and contributes to the pathogenesis of gastric cancer and peptic ulcer disease. We observed that purified VacA has relatively little effect on the viability of AGS gastric epithelial cells, but the presence of exogenous weak bases such as ammonium chloride (NH4Cl) enhances the susceptibility of these cells to VacA-induced vacuolation and cell death. Therefore, we tested the hypothesis that NH4Cl augments VacA toxicity by altering the intracellular trafficking of VacA or inhibiting intracellular VacA degradation. We observed VacA colocalization with LAMP1- and LC3-positive vesicles in both the presence and absence of NH4Cl, indicating that NH4Cl does not alter VacA trafficking to lysosomes or autophagosomes. Conversely, we found that supplemental NH4Cl significantly increases the intracellular stability of VacA. By conducting experiments using chemical inhibitors, stable ATG5 knockdown cell lines, and ATG16L1 knockout cells (generated using CRISPR/Cas9), we show that VacA degradation is independent of autophagy and proteasome activity but dependent on lysosomal acidification. We conclude that weak bases like ammonia, potentially generated during H. pylori infection by urease and other enzymes, enhance VacA toxicity by inhibiting toxin degradation.
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32
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Lee MH, Yang JY, Cho Y, Woo HJ, Kwon HJ, Kim DH, Park M, Moon C, Yeon MJ, Kim HW, Seo WD, Kim SH, Kim JB. Inhibitory Effects of Menadione on Helicobacter pylori Growth and Helicobacter pylori-Induced Inflammation via NF-κB Inhibition. Int J Mol Sci 2019; 20:ijms20051169. [PMID: 30866458 PMCID: PMC6429389 DOI: 10.3390/ijms20051169] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2019] [Revised: 03/01/2019] [Accepted: 03/04/2019] [Indexed: 12/19/2022] Open
Abstract
H. pylori is classified as a group I carcinogen by WHO because of its involvement in gastric cancer development. Several reports have suggested anti-bacterial effects of menadione, although the effect of menadione on major virulence factors of H. pylori and H. pylori-induced inflammation is yet to be elucidated. In this study, therefore, we demonstrated that menadione has anti-H. pylori and anti-inflammatory effects. Menadione inhibited growth of H. pylori reference strains and clinical isolates. Menadione reduced expression of vacA in H. pylori, and translocation of VacA protein into AGS (gastric adenocarcinoma cell) was also decreased by menadione treatment. This result was concordant with decreased apoptosis in AGS cells infected with H. pylori. Moreover, cytotoxin-associated protein A (CagA) translocation into H. pylori-infected AGS cells was also decreased by menadione. Menadione inhibited expression of several type IV secretion system (T4SS) components, including virB2, virB7, virB8, and virB10, that are responsible for translocation of CagA into host cells. In particular, menadione inhibited nuclear factor kappa-light-chain-enhancer of activated B cell (NF-κB) activation and thereby reduced expression of the proinflammatory cytokines such as IL-1β, IL-6, IL-8, and TNF-α in AGS as well as in THP-1 (monocytic leukemia cell) cell lines. Collectively, these results suggest the anti-bacterial and anti-inflammatory effects of menadione against H. pylori.
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Affiliation(s)
- Min Ho Lee
- Department of Biomedical Laboratory Science, College of Health Sciences, Yonsei University, Wonju 26493, Korea.
- Forensic DNA Division, National Forensic Service, Wonju 26460, Korea.
| | - Ji Yeong Yang
- Department of Biomedical Laboratory Science, College of Health Sciences, Yonsei University, Wonju 26493, Korea.
| | - Yoonjung Cho
- Forensic DNA Division, National Forensic Service, Wonju 26460, Korea.
| | - Hyun Jun Woo
- Department of Clinical Laboratory Science, College of Medical Sciences, Daegu Haany University, Gyeongsan 38610, Korea.
| | - Hye Jin Kwon
- Department of Biomedical Laboratory Science, College of Health Sciences, Yonsei University, Wonju 26493, Korea.
| | - Do Hyun Kim
- Department of Biomedical Laboratory Science, College of Health Sciences, Yonsei University, Wonju 26493, Korea.
| | - Min Park
- Department of Biomedical Laboratory Science, Daekyeung University, Gyeongsan 38547, Korea.
| | - Cheol Moon
- Department of Clinical Laboratory Science, Semyung University, Jecheon 27136, Korea.
| | - Min Ji Yeon
- Natural Products Research Center, Korea Institute of Science and Technology (KIST) Gangneung 25451, Korea.
| | - Hyun Woo Kim
- Department of Biomedical Laboratory Science, College of Health Sciences, Yonsei University, Wonju 26493, Korea.
| | - Woo-Duck Seo
- National Institute of Crop Science (NICS), Rural Development Administration (RDA), Wanju-Gun 55365, Korea.
| | - Sa-Hyun Kim
- Department of Clinical Laboratory Science, Semyung University, Jecheon 27136, Korea.
| | - Jong-Bae Kim
- Department of Biomedical Laboratory Science, College of Health Sciences, Yonsei University, Wonju 26493, Korea.
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33
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Abstract
Helicobacter pylori chronically infects nearly half the world's population, yet most of those infected remain asymptomatic throughout their lifetime. The outcome of infection-peptic ulcer disease or gastric cancer versus asymptomatic colonization-is a product of host genetics, environmental influences, and differences in bacterial virulence factors. Here, we review the current understanding of the cag pathogenicity island (cagPAI), the vacuolating cytotoxin (VacA), and a large family of outer membrane proteins (OMPs), which are among the best understood H. pylori virulence determinants that contribute to disease. Each of these virulence factors is characterized by allelic and phenotypic diversity that is apparent within and across individuals, as well as over time, and modulates inflammation. From the bacterial perspective, inflammation is probably a necessary evil because it promotes nutrient acquisition, but at the cost of reduction in bacterial load and therefore decreases the chance of transmission to a new host. The general picture that emerges is one of a chronic bacterial infection that is dependent on both inducing and carefully regulating the host inflammatory response. A better understanding of these regulatory mechanisms may have implications for the control of chronic inflammatory diseases that are increasingly common causes of human morbidity and mortality.
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Affiliation(s)
- Sundus Javed
- Department of Medicine, Department of Microbiology & Immunology, Center for Comparative Medicine, University of California, Davis School of Medicine, Davis, CA, 95616, USA.,Department of Biosciences, COMSATS Institute of Information Technology, Islamabad, Pakistan
| | - Emma C Skoog
- Department of Medicine, Department of Microbiology & Immunology, Center for Comparative Medicine, University of California, Davis School of Medicine, Davis, CA, 95616, USA
| | - Jay V Solnick
- Department of Medicine, Department of Microbiology & Immunology, Center for Comparative Medicine, University of California, Davis School of Medicine, Davis, CA, 95616, USA. .,Center for Comparative Medicine, University of California, Davis, Davis, CA, 95616, USA.
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34
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Yeon MJ, Lee MH, Kim DH, Yang JY, Woo HJ, Kwon HJ, Moon C, Kim SH, Kim JB. Anti-inflammatory effects of Kaempferol on Helicobacter pylori-induced inflammation. Biosci Biotechnol Biochem 2018; 83:166-173. [PMID: 30286691 DOI: 10.1080/09168451.2018.1528140] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Inflammation induced by Helicobacter pylori infection related to gastric carcinogenesis. In this study, we have investigated the anti-inflammatory effect and its mechanism of kaempferol in the inflammatory response caused by H. pylori infection in vitro. We found that kaempferol reduced the expression of pro-inflammatory cytokines (TNF-α, IL-1β, and IL-8) and production of IL-8 in AGS cells. In addition, kaempferol suppressed translocation of cytotoxin-associated gene A (CagA) and vacuolating cytotoxin A (VacA) of H. pylori to AGS cells. It was due to decreased transcription of type IV secretion system (T4SS) components involved in CagA injection and secretion system subunit protein A (SecA) of type V secretion system (T5SS) involved in VacA secretion by kaempferol. In conclusion, kaempferol shows the anti-inflammatory effect by suppressing the translocation of CagA and VacA proteins and leading to the down-regulation of pro-inflammatory cytokines. Abbreviations: CagA: cytotoxin-associated gene A; VacA: vacuolating cytotoxin A; T4SS: type IV secretion systems; SecA: secretion system subunit protein A; T5SS: type V secretion system.
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Affiliation(s)
- Min Ji Yeon
- a Department of Biomedical Laboratory Science, College of Health Sciences , Yonsei University , Wonju , Republic of Korea
| | - Min Ho Lee
- b Forensic DNA Division , National Forensic Service , Wonju , Republic of Korea
| | - Do Hyun Kim
- a Department of Biomedical Laboratory Science, College of Health Sciences , Yonsei University , Wonju , Republic of Korea
| | - Ji Yeong Yang
- a Department of Biomedical Laboratory Science, College of Health Sciences , Yonsei University , Wonju , Republic of Korea
| | - Hyun Jun Woo
- a Department of Biomedical Laboratory Science, College of Health Sciences , Yonsei University , Wonju , Republic of Korea
| | - Hye Jin Kwon
- a Department of Biomedical Laboratory Science, College of Health Sciences , Yonsei University , Wonju , Republic of Korea
| | - Cheol Moon
- c Department of Clinical Laboratory Science , Semyung University , Jecheon , Republic of Korea
| | - Sa-Hyun Kim
- c Department of Clinical Laboratory Science , Semyung University , Jecheon , Republic of Korea
| | - Jong-Bae Kim
- a Department of Biomedical Laboratory Science, College of Health Sciences , Yonsei University , Wonju , Republic of Korea
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35
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Kim IJ, Lee J, Oh SJ, Yoon MS, Jang SS, Holland RL, Reno ML, Hamad MN, Maeda T, Chung HJ, Chen J, Blanke SR. Helicobacter pylori Infection Modulates Host Cell Metabolism through VacA-Dependent Inhibition of mTORC1. Cell Host Microbe 2018; 23:583-593.e8. [PMID: 29746831 DOI: 10.1016/j.chom.2018.04.006] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2017] [Revised: 03/15/2018] [Accepted: 04/17/2018] [Indexed: 12/15/2022]
Abstract
Helicobacter pylori (Hp) vacuolating cytotoxin (VacA) is a bacterial exotoxin that enters host cells and induces mitochondrial dysfunction. However, the extent to which VacA-dependent mitochondrial perturbations affect overall cellular metabolism is poorly understood. We report that VacA perturbations in mitochondria are linked to alterations in cellular amino acid homeostasis, which results in the inhibition of mammalian target of rapamycin complex 1 (mTORC1) and subsequent autophagy. mTORC1, which regulates cellular metabolism during nutrient stress, is inhibited during Hp infection by a VacA-dependent mechanism. This VacA-dependent inhibition of mTORC1 signaling is linked to the dissociation of mTORC1 from the lysosomal surface and results in activation of cellular autophagy through the Unc 51-like kinase 1 (Ulk1) complex. VacA intoxication results in reduced cellular amino acids, and bolstering amino acid pools prevents VacA-mediated mTORC1 inhibition. Overall, these studies support a model that Hp modulate host cell metabolism through the action of VacA at mitochondria.
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Affiliation(s)
- Ik-Jung Kim
- Department of Microbiology, University of Illinois, Urbana, IL 61801, USA
| | - Jeongmin Lee
- Department of Biochemistry, University of Illinois, Urbana, IL 61801, USA
| | - Seung J Oh
- Department of Biochemistry, University of Illinois, Urbana, IL 61801, USA
| | - Mee-Sup Yoon
- Department of Cell and Developmental Biology, University of Illinois, Urbana, IL 61801, USA; Department of Molecular Medicine, School of Medicine, Gachon University, Incheon 406-840, Republic of Korea
| | - Sung-Soo Jang
- Department of Molecular and Integrative Physiology, University of Illinois, Urbana, IL 61801, USA
| | - Robin L Holland
- Department of Pathobiology, University of Illinois, Urbana, IL 61801, USA
| | - Michael L Reno
- Department of Microbiology, University of Illinois, Urbana, IL 61801, USA
| | - Mohammed N Hamad
- Department of Microbiology, University of Illinois, Urbana, IL 61801, USA
| | - Tatsuya Maeda
- Institute of Molecular and Cellular Biosciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-0032, Japan
| | - Hee Jung Chung
- Department of Molecular and Integrative Physiology, University of Illinois, Urbana, IL 61801, USA
| | - Jie Chen
- Department of Cell and Developmental Biology, University of Illinois, Urbana, IL 61801, USA
| | - Steven R Blanke
- Department of Microbiology, University of Illinois, Urbana, IL 61801, USA; Institute for Genomic Biology, University of Illinois, Urbana, IL 61801, USA; Lead Contact.
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Raghunathan K, Foegeding NJ, Campbell AM, Cover TL, Ohi MD, Kenworthy AK. Determinants of Raft Partitioning of the Helicobacter pylori Pore-Forming Toxin VacA. Infect Immun 2018; 86:e00872-17. [PMID: 29531133 DOI: 10.1128/IAI.00872-17] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Helicobacter pylori, a Gram-negative bacterium, is a well-known risk factor for gastric cancer. H. pylori vacuolating cytotoxin A (VacA) is a secreted pore-forming toxin that induces a wide range of cellular responses. Like many other bacterial toxins, VacA has been hypothesized to utilize lipid rafts to gain entry into host cells. Here, we used giant plasma membrane vesicles (GPMVs) as a model system to understand the preferential partitioning of VacA into lipid rafts. We show that a wild-type (WT) toxin predominantly associates with the raft phase. Acid activation of VacA enhances binding of the toxin to GPMVs but is not required for raft partitioning. VacA mutant proteins with alterations at the amino terminus (resulting in impaired membrane channel formation) and a nonoligomerizing VacA mutant protein retain the ability to preferentially associate with lipid rafts. Consistent with these results, the isolated VacA p55 domain was capable of binding to lipid rafts. We conclude that the affinity of VacA for rafts is independent of its capacity to oligomerize or form membrane channels.
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Brennan DE, Dowd C, O’Morain C, McNamara D, Smith SM. Can bacterial virulence factors predict antibiotic resistant Helicobacter pylori infection? World J Gastroenterol 2018; 24:971-981. [PMID: 29531461 PMCID: PMC5840472 DOI: 10.3748/wjg.v24.i9.971] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/10/2018] [Revised: 02/05/2018] [Accepted: 02/09/2018] [Indexed: 02/06/2023] Open
Abstract
AIM To evaluate the association between virulence factor status and antibiotic resistance in Helicobacter pylori (H. pylori)-infected patients in Ireland.
METHODS DNA was extracted from antral and corpus biopsies obtained from 165 H. pylori-infected patients. Genotyping for clarithromycin and fluoroquinolone-mediating mutations was performed using the Genotype HelicoDR assay. cagA and vacA genotypes were investigated using PCR.
RESULTS Primary, secondary and overall resistance rates for clarithromycin were 50.5% (n = 53/105), 78.3% (n = 47/60) and 60.6% (n = 100/165), respectively. Primary, secondary and overall resistance rates for fluoroquinolones were 15.2% (n = 16/105) and 28.3% (n = 17/60) and 20% (n = 33/165), respectively. Resistance to both antibiotics was 12.4% (n = 13/105) in treatment-naïve patients, 25% (n = 15/60) in those previously treated and 17% (n = 28/165) overall. A cagA-positive genotype was detected in 22.4% (n = 37/165) of patient samples. The dominant vacA genotype was S1/M2 at 44.8% (n = 74/165), followed by S2/M2 at 26.7% (n = 44/165), S1/M1 at 23.6% (n = 39/165) and S2/M1 at 4.8% (n = 8/165). Primary clarithromycin resistance was significantly lower in cagA-positive strains than in cagA-negative strains [32% (n = 8/25) vs 56.3% (n = 45/80) P = 0.03]. Similarly, in patients infected with more virulent H. pylori strains bearing the vacA s1 genotype, primary clarithromycin resistance was significantly lower than in those infected with less virulent strains bearing the vacA s2 genotype, [41% (n = 32/78) vs 77.8% (n = 21/27) P = 0.0001]. No statistically significant association was found between primary fluoroquinolone resistance and virulence factor status.
CONCLUSION Genotypic H. pylori clarithromycin resistance is high and cagA-negative strains are dominant in our population. Less virulent (cagA-negative and vacA S2-containing) strains of H. pylori are associated with primary clarithromycin resistance.
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Affiliation(s)
- Denise E Brennan
- Department of Clinical Medicine, School of Medicine, Trinity College Dublin, Dublin D2, Ireland
| | - Colin Dowd
- Department of Clinical Medicine, School of Medicine, Trinity College Dublin, Dublin D2, Ireland
| | - Colm O’Morain
- Department of Clinical Medicine, School of Medicine, Trinity College Dublin, Dublin D2, Ireland
| | - Deirdre McNamara
- Department of Clinical Medicine, School of Medicine, Trinity College Dublin, Dublin D2, Ireland
| | - Sinéad M Smith
- Department of Clinical Medicine, School of Medicine, Trinity College Dublin, Dublin D2, Ireland
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Atrisco-Morales J, Martínez-Santos VI, Román-Román A, Alarcón-Millán J, De Sampedro-Reyes J, Cruz-Del Carmen I, Martínez-Carrillo DN, Fernández-Tilapa G. vacA s1m1 genotype and cagA EPIYA-ABC pattern are predominant among Helicobacter pylori strains isolated from Mexican patients with chronic gastritis. J Med Microbiol 2018; 67:314-324. [PMID: 29458667 PMCID: PMC5882077 DOI: 10.1099/jmm.0.000660] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Purpose Virulent genotypes of Helicobacter pylori vacA s1m1/cagA+/babA2+ have been associated with severe gastric diseases. VacA, CagA and BabA are polymorphic proteins, and their association with the disease is allele-dependent. The aims of this work were: (i) to determine the prevalence of H. pylori by type of chronic gastritis; (ii) to describe the frequency of cagA, babA2 and vacA genotypes in strains from patients with different types of chronic gastritis; (iii) to characterize the variable region of cagA alleles. Methodology A total of 164 patients with chronic gastritis were studied. Altogether, 50 H. pylori strains were isolated, and the status of cagA, babA2 and vacA genotypes was examined by PCR. cagA EPIYA segment identification was performed using PCR and sequencing of cagA fragments of six randomly selected strains. Results/Key findings The overall prevalence of H. pylori was 30.5 %. Eighty percent of the isolated strains were vacA s1m1, and the cagA and babA2 genes were detected in 74 and 32 % of the strains, respectively. The most frequent genotypes were vacA s1m1/cagA+/babA2- and vacA s1m1/cagA+/babA2+, with 40 % (20/50) and 28 % (14/50), respectively. In cagA+, the most frequent EPIYA motif was -ABC (78.4 %), and EPIYA-ABCC and -ABCCC motifs were found in 10.8 % of the strains. A modified EPIYT-B motif was found in 66.6 % of the sequenced strains. Conclusion H. pylori strains carrying vacA s1m1, cagA+ and babA2- genotypes were the most prevalent in patients with chronic gastritis from the south of Mexico. In the cagA+ strains, the EPIYA-ABC motif was the most common.
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Affiliation(s)
- Josefina Atrisco-Morales
- Laboratorio de Investigación Clínica, Facultad de Ciencias Químico-Biológicas, Universidad Autónoma de Guerrero, Av. Lázaro Cárdenas s/n C.U. Sur. Chilpancingo, Guerrero, C.P. 39090, Mexico
| | - Verónica I Martínez-Santos
- CONACYT Research Fellow- Universidad Autónoma de Guerrero, Facultad de Ciencias Químico-Biológicas, Universidad Autónoma de Guerrero, Guerrero, Mexico
| | - Adolfo Román-Román
- Laboratorio de Investigación en Bacteriología, Facultad de Ciencias Químico-Biológicas, Universidad Autónoma de Guerrero, Guerrero, Mexico
| | - Judit Alarcón-Millán
- Laboratorio de Investigación en Bacteriología, Facultad de Ciencias Químico-Biológicas, Universidad Autónoma de Guerrero, Guerrero, Mexico
| | | | | | - Dinorah N Martínez-Carrillo
- Laboratorio de Investigación Clínica, Facultad de Ciencias Químico-Biológicas, Universidad Autónoma de Guerrero, Av. Lázaro Cárdenas s/n C.U. Sur. Chilpancingo, Guerrero, C.P. 39090, Mexico
| | - Gloria Fernández-Tilapa
- Laboratorio de Investigación Clínica, Facultad de Ciencias Químico-Biológicas, Universidad Autónoma de Guerrero, Av. Lázaro Cárdenas s/n C.U. Sur. Chilpancingo, Guerrero, C.P. 39090, Mexico
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Nakano M, Yahiro K, Yamasaki E, Kurazono H, Akada J, Yamaoka Y, Niidome T, Hatakeyama M, Suzuki H, Yamamoto T, Moss J, Isomoto H, Hirayama T. Helicobacter pylori VacA, acting through receptor protein tyrosine phosphatase α, is crucial for CagA phosphorylation in human duodenum carcinoma cell line AZ-521. Dis Model Mech 2017; 9:1473-1481. [PMID: 27935824 PMCID: PMC5200893 DOI: 10.1242/dmm.025361] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2016] [Accepted: 10/11/2016] [Indexed: 12/16/2022] Open
Abstract
Helicobacter pylori, a major cause of gastroduodenal diseases, produces vacuolating cytotoxin (VacA) and cytotoxin-associated gene A (CagA), which seem to be involved in virulence. VacA exhibits pleiotropic actions in gastroduodenal disorders via its specific receptors. Recently, we found that VacA induced the phosphorylation of cellular Src kinase (Src) at Tyr418 in AZ-521 cells. Silencing of receptor protein tyrosine phosphatase (RPTP)α, a VacA receptor, reduced VacA-induced Src phosphorylation. Src is responsible for tyrosine phosphorylation of CagA at its Glu-Pro-Ile-Tyr-Ala (EPIYA) variant C (EPIYA-C) motif in Helicobacterpylori-infected gastric epithelial cells, resulting in binding of CagA to SHP-2 phosphatase. Challenging AZ-521 cells with wild-type H. pylori induced phosphorylation of CagA, but this did not occur when challenged with a vacA gene-disrupted mutant strain. CagA phosphorylation was observed in cells infected with a vacA gene-disrupted mutant strain after addition of purified VacA, suggesting that VacA is required for H. pylori-induced CagA phosphorylation. Following siRNA-mediated RPTPα knockdown in AZ-521 cells, infection with wild-type H. pylori and treatment with VacA did not induce CagA phosphorylation. Taken together, these results support our conclusion that VacA mediates CagA phosphorylation through RPTPα in AZ-521 cells. These data indicate the possibility that Src phosphorylation induced by VacA is mediated through RPTPα, resulting in activation of Src, leading to CagA phosphorylation at Tyr972 in AZ-521 cells. Summary: The authors show a newly identified role of VacA in Helicobacter pylori infection through induction of tyrosine phosphorylation of CagA acting through the VacA receptor RPTPα.
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Affiliation(s)
- Masayuki Nakano
- Department of Bacteriology, Institute of Tropical Medicine, Nagasaki University, 1-12-4, Sakamoto, Nagasaki 852-8523, Japan .,Department of International Health, Institute of Tropical Medicine, Nagasaki University, 1-12-4, Sakamoto, Nagasaki 852-8523, Japan
| | - Kinnosuke Yahiro
- Department of Molecular Infectiology, Graduate School of Medicine, Chiba University, 1-8-1, Inohana, Chuo-ku, Chiba 260-8670, Japan
| | - Eiki Yamasaki
- Division of Food Hygiene, Department of Animal and Food Hygiene, Obihiro University of Agriculture and Veterinary Medicine, Nishi 2-11, Inada-cho, Obihiro, Hokkaido 080-8555, Japan
| | - Hisao Kurazono
- Division of Food Hygiene, Department of Animal and Food Hygiene, Obihiro University of Agriculture and Veterinary Medicine, Nishi 2-11, Inada-cho, Obihiro, Hokkaido 080-8555, Japan
| | - Junko Akada
- Department of Environmental and Preventive Medicine, Oita University Faculty of Medicine, Idaigaoka 1-1, Yufu, Oita 879-5593, Japan
| | - Yoshio Yamaoka
- Department of Environmental and Preventive Medicine, Oita University Faculty of Medicine, Idaigaoka 1-1, Yufu, Oita 879-5593, Japan.,Department of Medicine, Gastroenterology and Hepatology Section, Baylor College of Medicine, Houston, TX 77030, USA
| | - Takuro Niidome
- Department of Applied Chemistry and Biochemistry, Graduate School of Science and Technology, Kumamoto University, 2-39-1 Kurokami, Chuo-ku, Kumamoto 860-8555, Japan
| | - Masanori Hatakeyama
- Division of Microbiology, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-Ku, Tokyo 113-0033, Japan
| | - Hidekazu Suzuki
- Medical Education Center, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan
| | - Taro Yamamoto
- Department of International Health, Institute of Tropical Medicine, Nagasaki University, 1-12-4, Sakamoto, Nagasaki 852-8523, Japan
| | - Joel Moss
- Cardiovascular and Pulmonary Branch, NHLBI, National Institutes of Health, Bethesda, MD 20892-1590, USA
| | - Hajime Isomoto
- Division of Medicine and Clinical Science, Tottori University Faculty of Medicine, 86 Nishi-cho, Yonago, Tottori 683-8503, Japan
| | - Toshiya Hirayama
- Department of Bacteriology, Institute of Tropical Medicine, Nagasaki University, 1-12-4, Sakamoto, Nagasaki 852-8523, Japan
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INAGAKI TOMOKO, NISHIUMI SHIN, ITO YOSHIYUKI, YAMAKAWA AKIYO, YAMAZAKI YUKINAO, YOSHIDA MASARU, AZUMA TAKESHI. Associations Between CagA, VacA, and the Clinical Outcomes of Helicobacter Pylori Infections in Okinawa, Japan. Kobe J Med Sci 2017; 63:E58-E67. [PMID: 29434176 PMCID: PMC5826021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 07/19/2017] [Accepted: 08/25/2017] [Indexed: 06/08/2023]
Abstract
Helicobacter pylori, which is involved in the pathogenesis of gastroduodenal disease, produces CagA and VacA as major virulence factors. CagA is classified into East Asian and Western types based on the number and sequences of its Glu-Pro-Ile-Tyr-Ala motifs. The vacA gene has three polymorphic regions: the signal (s), intermediate (i), and middle (m) regions. The lowest gastric cancer mortality rate is seen in Okinawa. On the Japanese mainland (Honshu), most H. pylori produce s1/m1-VacA, which exhibits strong toxicity, and East Asian-type CagA. However, the H. pylori detected in Okinawa produces s1/m2-VacA, which exhibits weak toxicity, or s2/m2-VacA, which is non-toxic, and Western-type CagA. Studies about the i-region of vacA have been performed around the world, but there have been few such studies in Japan. Therefore, the aim of this study was to assess the relationships between the clinical outcomes of H. pylori infections in Okinawa, vacA (especially the i-region genotype), and cagA. H. pylori strains that were collected from patients with gastric cancer or gastric ulcers in Okinawa only produced the i1-type VacA virulence factor. The vacuolating cytotoxin activity of i1-type VacA was stronger than that of i2-type VacA, suggesting that the i-region genotype of vacA is closely associated with vacuolating cytotoxin activity. These results indicate that the i-region genotype of vacA is a useful marker of both H. pylori virulence and the clinical outcomes of H. pylori infections in Okinawa, Japan.
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Affiliation(s)
- TOMOKO INAGAKI
- Division of Gastroenterology, Department of Internal Medicine, Kobe University Graduate School of Medicine, Kobe, Japan
| | - SHIN NISHIUMI
- Division of Gastroenterology, Department of Internal Medicine, Kobe University Graduate School of Medicine, Kobe, Japan
| | | | | | | | - MASARU YOSHIDA
- Division of Gastroenterology, Department of Internal Medicine, Kobe University Graduate School of Medicine, Kobe, Japan
- Division of Metabolomics Research, Department of Internal Related, Kobe University Graduate School of Medicine, Kobe, Japan
| | - TAKESHI AZUMA
- Division of Gastroenterology, Department of Internal Medicine, Kobe University Graduate School of Medicine, Kobe, Japan
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Álvarez A, Uribe F, Canales J, Romero C, Soza A, Peña MA, Antonelli M, Almarza O, Cerda O, Toledo H. KCTD5 and Ubiquitin Proteasome Signaling Are Required for Helicobacter pylori Adherence. Front Cell Infect Microbiol 2017; 7:450. [PMID: 29114497 PMCID: PMC5660694 DOI: 10.3389/fcimb.2017.00450] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2017] [Accepted: 10/04/2017] [Indexed: 12/19/2022] Open
Abstract
In order to establish infection, bacterial pathogens modulate host cellular processes by using virulence factors, which are delivered from the bacteria to the host cell leading to cellular reprogramming. In this context, several pathogens regulate the ubiquitin proteasome system in order to regulate the cellular effectors required for their successful colonization and persistance. In this study, we investigated how Helicobacter pylori affect the ubiquitination of the host proteins to achieve the adherence to the cells, using AGS gastric epithelial cells cultured with H. pylori strains, H. pylori 26695 and two isogenic mutants H. pylori cag::cat and vacA::apha3, to characterize the ability of H. pylori to reprogram the ubiquitin proteasome systems. The infection assays suggest that the ubiquitination of the total proteins does not change when cells were co-culture with H. pylori. We also found that the proteasome activity is necessary for H. pylori adhesion to AGS cells and the adherence increases when the level of KCTD5, an adaptor of Cullin-3, decrease. Moreover, we found that KCTD5 is ubiquitinated and degraded by the proteasome system and that CagA and VacA played no role on reducing KCTD5 levels. Furthermore, H. pylori impaired KCTD5 ubiquitination and did not increase global proteasome function. These results suggest that H. pylori affect the ubiquitin-proteasome system (UPS) to facilitate the adhesion of this microorganism to establish stable colonization in the gastric epithelium and improve our understanding of how H. pylori hijack host systems to establish the adherence.
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Affiliation(s)
- Alhejandra Álvarez
- Molecular and Cellular Biology Program, Faculty of Medicine, Instituto de Ciencias Biomédicas (ICBM), Universidad de Chile, Santiago, Chile
| | - Felipe Uribe
- Molecular and Cellular Biology Program, Faculty of Medicine, Instituto de Ciencias Biomédicas (ICBM), Universidad de Chile, Santiago, Chile
| | - Jimena Canales
- Molecular and Cellular Biology Program, Faculty of Medicine, Instituto de Ciencias Biomédicas (ICBM), Universidad de Chile, Santiago, Chile
| | - Cristóbal Romero
- Molecular and Cellular Biology Program, Faculty of Medicine, Instituto de Ciencias Biomédicas (ICBM), Universidad de Chile, Santiago, Chile
| | - Andrea Soza
- Department of Biological and Chemical Sciences, Faculty of Science, Universidad San Sebastián, Santiago, Chile
| | - María A Peña
- Molecular and Cellular Biology Program, Faculty of Medicine, Instituto de Ciencias Biomédicas (ICBM), Universidad de Chile, Santiago, Chile
| | - Marcelo Antonelli
- Molecular and Cellular Biology Program, Faculty of Medicine, Instituto de Ciencias Biomédicas (ICBM), Universidad de Chile, Santiago, Chile
| | - Oscar Almarza
- Molecular and Cellular Biology Program, Faculty of Medicine, Instituto de Ciencias Biomédicas (ICBM), Universidad de Chile, Santiago, Chile
| | - Oscar Cerda
- Molecular and Cellular Biology Program, Faculty of Medicine, Instituto de Ciencias Biomédicas (ICBM), Universidad de Chile, Santiago, Chile.,Millennium Nucleus of Ion Channels-Associated Diseases (MiNICAD), Santiago, Chile
| | - Héctor Toledo
- Molecular and Cellular Biology Program, Faculty of Medicine, Instituto de Ciencias Biomédicas (ICBM), Universidad de Chile, Santiago, Chile
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Link A, Langner C, Schirrmeister W, Habendorf W, Weigt J, Venerito M, Tammer I, Schlüter D, Schlaermann P, Meyer TF, Wex T, Malfertheiner P. Helicobacter pylori vacA genotype is a predominant determinant of immune response to Helicobacter pylori CagA. World J Gastroenterol 2017; 23:4712-4723. [PMID: 28765692 PMCID: PMC5514636 DOI: 10.3748/wjg.v23.i26.4712] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/19/2017] [Revised: 04/05/2017] [Accepted: 05/19/2017] [Indexed: 02/06/2023] Open
Abstract
AIM To evaluate the frequency of Helicobacter pylori (H. pylori) CagA antibodies in H. pylori infected subjects and to identify potential histopathological and bacterial factors related to H. pylori CagA-immune response.
METHODS Systematic data to H. pylori isolates, blood samples, gastric biopsies for histological and molecular analyses were available from 99 prospectively recruited subjects. Serological profile (anti-H. pylori, anti-CagA) was correlated with H. pylori isolates (cagA, EPIYA, vacA s/m genotype), histology (Sydney classification) and mucosal interleukin-8 (IL-8) mRNA and protein expression. Selected H. pylori strains were assessed for H. pylori CagA protein expression and IL-8 induction in co-cultivation model with AGS cells.
RESULTS Thirty point three percent of microbiologically confirmed H. pylori infected patients were seropositive for CagA. Majority of H. pylori isolates were cagA gene positive (93.9%) with following vacA polymorphisms: 42.4% vacA s1m1, 23.2% s1m2 and 34.3% s2m2. Anti-CagA-IgG seropositivity was strongly associated with atrophic gastritis, increased mucosal inflammation according to the Sydney score, IL-8 and cagA mRNA expression. VacA s and m polymorphisms were the major determinants for positive (vacA s1m1) or negative (vacA s2m2) anti-CagA serological immune response, which also correlated with the in vitro inflammatory potential in AGS cells. In vitro co-cultivation of representative H. pylori strains with AGS cells confirmed functional CagA translocation, which showed only partial correlation with CagA seropositivity in patients, supporting vacA as major co-determinant of the immune response.
CONCLUSION Serological immune response to H. pylori cagA+ strain in H. pylori infected patients is strongly associated with vacA polymorphism, suggesting the crucial role of bacterial factors in immune and clinical phenotype of the infection.
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Fahimi F, Tohidkia MR, Fouladi M, Aghabeygi R, Samadi N, Omidi Y. Pleiotropic cytotoxicity of VacA toxin in host cells and its impact on immunotherapy. ACTA ACUST UNITED AC 2017; 7:59-71. [PMID: 28546954 PMCID: PMC5439391 DOI: 10.15171/bi.2017.08] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2017] [Revised: 02/09/2017] [Accepted: 02/13/2017] [Indexed: 12/17/2022]
Abstract
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Introduction: In the recent decades, a number of studies have highlighted the importance of Helicobacter pylori in the initiation and development of peptic ulcer and gastric cancer. Some potential virulence factors (e.g., urease, CagA, VacA, BabA) are exploited by this microorganism, facilitating its persistence through evading human defense mechanisms. Among these toxins and enzymes, vacuolating toxin A (VacA) is of a great importance in the pathogenesis of H. pylori. VacA toxin shows different pattern of cytotoxicity through binding to different cell surface receptors in various cells.
Methods: To highlight attempts in treatment for H. pylori infection, here, we discussed the VacA potential as a candidate for development of vaccine and targeted immunotherapy. Furthermore, we reviewed the related literature to provide key insights on association of the genetic variants of VacA with the toxicity of the toxin in cells.
Results: A number of investigations on the receptor(s) binding of VacA toxin confirmed the pleiotropic nature of VacA that uses a unique mechanism for internalization through some membrane components such as lipid rafts and glycophosphatidylinositol (GPI)-anchored proteins (GPI-AP). Considering the high potency of VacA toxin in the clinical presentations in infection and assisting persistence and colonization of H. pylori, it is considered as one of the pivotal components in production vaccines and monoclonal antibodies (mAbs).
Conclusion: It is possible to generate mAbs with a considerable potential to convert into secretory immunoglobulins that could penetrate into the niche of H. pylori and inhibit its normal functionalities. Further, conjugation of H. pylori targeting Ab fragments with the toxic agents or drug delivery systems (DDSs) offers new generation of H. pylori treatments.
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Affiliation(s)
- Farnaz Fahimi
- Research Center for Pharmaceutical Nanotechnology, Biomedicine Institute, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Mohammad Reza Tohidkia
- Research Center for Pharmaceutical Nanotechnology, Biomedicine Institute, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Mehdi Fouladi
- Research Center for Pharmaceutical Nanotechnology, Biomedicine Institute, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Reza Aghabeygi
- School of Advanced Biomedical Sciences, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Naser Samadi
- School of Advanced Biomedical Sciences, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Yadollah Omidi
- Research Center for Pharmaceutical Nanotechnology, Biomedicine Institute, Tabriz University of Medical Sciences, Tabriz, Iran.,School of Advanced Biomedical Sciences, Tabriz University of Medical Sciences, Tabriz, Iran.,Department of Pharmaceutics, Faculty of Pharmacy, Tabriz University of Medical Sciences, Tabriz, Iran
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Backert S, Schmidt TP, Harrer A, Wessler S. Exploiting the Gastric Epithelial Barrier: Helicobacter pylori’s Attack on Tight and Adherens Junctions. In: Tegtmeyer N, Backert S, editors. Molecular Pathogenesis and Signal Transduction by Helicobacter pylori. Cham: Springer International Publishing; 2017. pp. 195-226. [DOI: 10.1007/978-3-319-50520-6_9] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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Abstract
Helicobacter pylori is estimated to infect more than half of the worlds human population and represents a major risk factor for chronic gastritis, peptic ulcer disease, MALT lymphoma, and gastric adenocarcinoma. H. pylori infection and clinical consequences are controlled by highly complex interactions between the host, colonizing bacteria, and environmental parameters. Important bacterial determinants linked with gastric disease development include the cag pathogenicity island encoding a type IV secretion system (T4SS), the translocated effector protein CagA, vacuolating cytotoxin VacA, adhesin BabA, urease, serine protease HtrA, secreted outer membrane vesicles, and many others. The high quantity of these factors and allelic changes in the corresponding genes reveals a sophisticated picture and problems in evaluating the impact of each distinct component. Extensive work has been performed to pinpoint molecular processes related to H. pylori-triggered pathogenesis using Mongolian gerbils, mice, primary tissues, as well as novel in vitro model systems such as gastroids. The manipulation of host signaling cascades by the bacterium appears to be crucial for inducing pathogenic downstream activities and gastric disease progression. Here, we review the most recent advances in this important research area.
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Affiliation(s)
- Steffen Backert
- Division of Microbiology, Department of Biology, Friedrich Alexander University Erlangen-Nuremberg, Erlangen, Germany
| | - Matthias Neddermann
- Division of Microbiology, Department of Biology, Friedrich Alexander University Erlangen-Nuremberg, Erlangen, Germany
| | - Gunter Maubach
- Institute of Experimental Internal Medicine, Otto von Guericke University, Magdeburg, Germany
| | - Michael Naumann
- Institute of Experimental Internal Medicine, Otto von Guericke University, Magdeburg, Germany
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Abstract
One of the major toxins secreted by H. pylori is the Vacuolating cytotoxin A (VacA) named after its ability to induce the formation of “vacuole”-like membrane vesicles in the cytoplasm of gastric cells. VacA has been associated with the disruption of mitochondrial functions, stimulation of apoptosis, blockade of T cell proliferation and promotion of regulatory T cells, thereby making it a promising vaccine target. Immunity to bacterial virulence factors is well known to protect humans against bacterial infections; hence, detoxified VacA has been evaluated as a vaccine antigen. Our short review summarizes the pre-clinical and clinical data that have been published on the use of VacA in the development of the H. pylori vaccine.
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Kyrillos A, Arora G, Murray B, Rosenwald AG. The Presence of Phage Orthologous Genes in Helicobacter pylori Correlates with the Presence of the Virulence Factors CagA and VacA. Helicobacter 2016; 21:226-33. [PMID: 26612095 DOI: 10.1111/hel.12282] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
BACKGROUND The bacterium Helicobacter pylori is associated with ulcers and the development of gastric cancer. Several genes, including cytotoxin-associated gene A (CagA) and vacuolating cytotoxin A (VacA), are associated with increased gastric cancer risk. Some strains of H. pylori also contain sequences related to bacteriophage phiHP33; however, the significance of these phage-related sequences remains unknown. MATERIALS AND METHODS We assessed the extent to which phiHP33-related sequences are present in 335 H. pylori strains using homology searches then mapped shared genes between phiHP33 and H. pylori strains onto an existing phylogeny. RESULTS One hundred and twenty-one H. pylori strains contain phage orthologous sequences, and the presence of the phage-related sequences correlates with the presence of CagA and VacA. Mapping of the phage orthologs onto a phylogeny of H. pylori is consistent with the hypothesis that these genes were acquired by horizontal gene transfer. CONCLUSIONS phiHP33 phage orthologous sequences might be of significance in understanding virulence of different H. pylori strains.
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Affiliation(s)
| | - Gaurav Arora
- Department of Biology, Georgetown University, Washington, DC, USA
| | - Bradley Murray
- Department of Biology, Georgetown University, Washington, DC, USA
| | - Anne G Rosenwald
- Department of Biology, Georgetown University, Washington, DC, USA
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Noche CD, Njajou O, Etoa FX. No Association between CagA- and VacA-Positive Strains of Helicobacter pylori and Primary Open-Angle Glaucoma: A Case-Control Study. Ophthalmol Eye Dis 2016; 8:1-4. [PMID: 26917977 PMCID: PMC4758802 DOI: 10.4137/oed.s35895] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Revised: 12/03/2015] [Accepted: 12/04/2015] [Indexed: 12/20/2022]
Abstract
INTRODUCTION Glaucoma is a public health issue worldwide, particularly in Africa. In Cameroon, the prevalence rate of primary open-angle glaucoma (POAG) ranges between 4.5% and 8.2%. Helicobacter pylori (HP) has been implicated in digestive and extra-digestive diseases, including glaucoma. The objective of this work was to evaluate the implication of CagA- and VacA-positive strains of HP in POAG using a case-control design. METHODS An analytical study was conducted from October 2013 to December 2013. Participants were recruited in eye care centers in Yaoundé. Enzyme-linked immunosorbent assays (ELISAs) were carried out in the La Grace Laboratory in Yaoundé. RESULTS The total sample consisted of 50 POAG patients and 31 controls with a mean age of 58.5 ± 12.2 years and 45.5 ± 14.6 years, respectively. The prevalence rates of HP in the POAG and control groups were 74% (37/50) and 87% (27/31), respectively (P = 0.125). The prevalence rates of CagA-positive HP seropositivity in the POAG and control groups were 26% and 22.58%, respectively (P = 0.47), and the prevalence rates of VacA-positive HP participants were 6% and 0%, respectively (P = 0.22). CONCLUSION The HP prevalence rates among POAG patients and controls were 74% and 87%, respectively. There was no significant difference between prevalence rates of HP in the POAG and control groups. There was no association between POAG and CagA- or VacA-positive HP infection.
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Affiliation(s)
- C Domngang Noche
- Faculty of Health Sciences, Université des Montagnes, Bangangté, Cameroon.; Faculty of Sciences, Department of Microbiology, Université de Yaoundé I, Yaoundé, Cameroon
| | - O Njajou
- Faculty of Health Sciences, Université des Montagnes, Bangangté, Cameroon
| | - F X Etoa
- Faculty of Sciences, Department of Microbiology, Université de Yaoundé I, Yaoundé, Cameroon
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Chang H, Chen D, Ni B, Zuo Q, Wang C, Han R, Lan C. Cortactin Mediates Apoptosis of Gastric Epithelial Cells Induced by VacA Protein of Helicobacter pylori. Dig Dis Sci 2016; 61:80-90. [PMID: 26289258 DOI: 10.1007/s10620-015-3836-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/04/2015] [Accepted: 07/30/2015] [Indexed: 12/11/2022]
Abstract
BACKGROUND Vacuolating cytotoxin antigen (VacA) is one of the major virulence factors in Helicobacter pylori (H. pylori), which is responsible for cell vacuolar degeneration and apoptotic cell death. A candidate host factor which mediates this process is cortactin, a protein associated with the processes of colonization and adhesion of H. pylori in gastric epithelium. AIM To investigate the role of cortactin in VacA-induced apoptosis of gastric epithelial cells. METHODS Cortactin expression and shRNA lentiviral constructs were developed and transduced into the human gastric cancer cell line, AGS. VacA protein was purified from H. pylori cultures, acid-activated, and co-incubated with the transduced cell populations. Apoptosis was detected by flow cytometry, and the levels of the pro- and anti-apoptotic proteins Bax and Bcl-2 were determined by Western blot. RESULTS Acid-activated purified VacA induced apoptosis in the parental AGS cells. Increased expression of cortactin (AGS/cortactin) led to a greater percentage of cells undergoing apoptosis. In contrast, knockdown of cortactin with shRNA (AGS/cortactin-shRNA) decreased the percentage of apoptotic cells. The protein levels of pro- and anti-apoptotic proteins Bax and Bcl-2 were increased and decreased in AGS/cortactin cells relative to the parental AGS cells. In the AGS/cortactin-shRNA cells, Bax protein levels were decreased, while Bcl-2 protein was increased. CONCLUSIONS The results indicate that cortactin is involved in the regulation of apoptosis induced by VacA in gastric cells.
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Snider CA, Voss BJ, McDonald WH, Cover TL. Growth phase-dependent composition of the Helicobacter pylori exoproteome. J Proteomics 2016; 130:94-107. [PMID: 26363098 DOI: 10.1016/j.jprot.2015.08.025] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2015] [Revised: 08/28/2015] [Accepted: 08/31/2015] [Indexed: 12/11/2022]
Abstract
Helicobacter pylori colonizes the human stomach and is associated with an increased risk of gastric cancer and peptic ulcer disease. Analysis of H. pylori protein secretion is complicated by the occurrence of bacterial autolysis. In this study, we analyzed the exoproteome of H. pylori at multiple phases of bacterial growth and identified 74 proteins that are selectively released into the extracellular space. These include proteins known to cause alterations in host cells, antigenic proteins, and additional proteins that have not yet been studied in any detail. The composition of the H. pylori exoproteome is dependent on the phase of bacterial growth. For example, the proportional abundance of the vacuolating toxin VacA in culture supernatant is higher during late growth phases than early growth phases, whereas the proportional abundance of many other proteins is higher during early growth phases. We detected marked variation in the subcellular localization of putative secreted proteins within soluble and membrane fractions derived from intact bacteria. By providing a comprehensive view of the H. pylori exoproteome, these results provide new insights into the array of secreted H. pylori proteins that may cause alterations in the gastric environment.
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