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Jing S, Lin L, Li J, Pan J, Qiao X. Causal relationship between Helicobacter pylori infection and IgA nephropathy: a bidirectional two-sample mendelian randomization study. Ren Fail 2024; 46:2371055. [PMID: 38946159 PMCID: PMC467090 DOI: 10.1080/0886022x.2024.2371055] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2024] [Accepted: 06/17/2024] [Indexed: 07/02/2024] Open
Abstract
IgA nephropathy (IgAN) is one of the most common primary glomerulonephritis, and serum Helicobacter pylori (H. pylori) antibody levels are increased in patients with IgA N, but the role of H. pylori infection in the pathogenesis of IgAN is unclear. In this study, we investigated whether there is a causal relationship and reverse causality between IgAN and H. pylori infection by using a bidirectional two-sample Mendelian randomization (MR) analysis. This study was estimated using inverse variance weighted (IVW), MR-Egger and weighted median methods, with the IVW method having the strongest statistical efficacy. Seven common serum H. pylori antibodies were selected as exposure factors for positive MR analysis. The results showed that there was no evidence of a causal relationship between H. pylori infection and IgAN. Reverse MR analysis showed that there was also no evidence that the occurrence of IgAN leads to an increased risk of H. pylori infection.
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Affiliation(s)
- Shuhui Jing
- Department of Nephrology, Second Hospital of Shanxi Medical University, Taiyuan, People’s Republic of China
- Shanxi Kidney Disease Institute, Taiyuan, People’s Republic of China
- Kidney Research Center of Shanxi Medical University, Taiyuan, People’s Republic of China
| | - Ling Lin
- Department of Nephrology, Second Hospital of Shanxi Medical University, Taiyuan, People’s Republic of China
- Shanxi Kidney Disease Institute, Taiyuan, People’s Republic of China
- Kidney Research Center of Shanxi Medical University, Taiyuan, People’s Republic of China
| | - Jiaxing Li
- Department of General Surgery, The Second Hospital of Shanxi Medical University, Taiyuan, People’s Republic of China
| | - Juan Pan
- Department of Nephrology, Second Hospital of Shanxi Medical University, Taiyuan, People’s Republic of China
- Shanxi Kidney Disease Institute, Taiyuan, People’s Republic of China
- Kidney Research Center of Shanxi Medical University, Taiyuan, People’s Republic of China
| | - Xi Qiao
- Department of Nephrology, Second Hospital of Shanxi Medical University, Taiyuan, People’s Republic of China
- Shanxi Kidney Disease Institute, Taiyuan, People’s Republic of China
- Kidney Research Center of Shanxi Medical University, Taiyuan, People’s Republic of China
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2
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Lee YT, Senturk M, Guan Y, Wang MC. Bacteria-organelle communication in physiology and disease. J Cell Biol 2024; 223:e202310134. [PMID: 38748249 PMCID: PMC11096858 DOI: 10.1083/jcb.202310134] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2023] [Revised: 04/03/2024] [Accepted: 05/03/2024] [Indexed: 05/18/2024] Open
Abstract
Bacteria, omnipresent in our environment and coexisting within our body, exert dual beneficial and pathogenic influences. These microorganisms engage in intricate interactions with the human body, impacting both human health and disease. Simultaneously, certain organelles within our cells share an evolutionary relationship with bacteria, particularly mitochondria, best known for their energy production role and their dynamic interaction with each other and other organelles. In recent years, communication between bacteria and mitochondria has emerged as a new mechanism for regulating the host's physiology and pathology. In this review, we delve into the dynamic communications between bacteria and host mitochondria, shedding light on their collaborative regulation of host immune response, metabolism, aging, and longevity. Additionally, we discuss bacterial interactions with other organelles, including chloroplasts, lysosomes, and the endoplasmic reticulum (ER).
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Affiliation(s)
- Yi-Tang Lee
- Waisman Center, University of Wisconsin, Madison, WI, USA
- Huffington Center on Aging, Baylor College of Medicine, Houston, TX, USA
- Integrative Program of Molecular and Biochemical Sciences, Baylor College of Medicine, Houston, TX, USA
| | - Mumine Senturk
- Huffington Center on Aging, Baylor College of Medicine, Houston, TX, USA
- Howard Hughes Medical Institute, Baylor College of Medicine, Houston, TX, USA
| | - Youchen Guan
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX, USA
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA
| | - Meng C. Wang
- Howard Hughes Medical Institute, Baylor College of Medicine, Houston, TX, USA
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA
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3
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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 2023; 14:11. [PMID: 38248700 PMCID: PMC10821523 DOI: 10.3390/membranes14010011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [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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4
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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] [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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5
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Holland RL, Bosi KD, Seeger AY, Blanke SR. Restoration of mitochondrial structure and function within Helicobacter pylori VacA intoxicated cells. ADVANCES IN MICROBIOLOGY 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] [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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6
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Maurice NM, Sadikot RT. Mitochondrial Dysfunction in Bacterial Infections. Pathogens 2023; 12:1005. [PMID: 37623965 PMCID: PMC10458073 DOI: 10.3390/pathogens12081005] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2023] [Revised: 07/23/2023] [Accepted: 07/26/2023] [Indexed: 08/26/2023] Open
Abstract
Mitochondria are critical in numerous cellular processes, including energy generation. Bacterial pathogens target host cell mitochondria through various mechanisms to disturb the host response and improve bacterial survival. We review recent advances in the understanding of how bacteria cause mitochondrial dysfunction through perturbations in mitochondrial cell-death pathways, energy production, mitochondrial dynamics, mitochondrial quality control, DNA repair, and the mitochondrial unfolded protein response. We also briefly highlight possible therapeutic approaches aimed at restoring the host mitochondrial function as a novel strategy to enhance the host response to bacterial infection.
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Affiliation(s)
- Nicholas M. Maurice
- Department of Medicine, Division of Pulmonary, Allergy, Critical Care, and Sleep Medicine, Emory University School of Medicine, Atlanta, GA 30322, USA
- Atlanta Veterans Affairs Health Care System, Decatur, GA 30033, USA
| | - Ruxana T. Sadikot
- VA Nebraska Western Iowa Health Care System, Omaha, NE 68105, USA
- Division of Pulmonary, Critical Care & Sleep, Department of Internal Medicine, University of Nebraska Medical Center, Omaha, NE 68198, USA
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7
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Reyes VE. Helicobacter pylori and Its Role in Gastric Cancer. Microorganisms 2023; 11:1312. [PMID: 37317287 PMCID: PMC10220541 DOI: 10.3390/microorganisms11051312] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2023] [Revised: 05/08/2023] [Accepted: 05/15/2023] [Indexed: 06/16/2023] Open
Abstract
Gastric cancer is a challenging public health concern worldwide and remains a leading cause of cancer-related mortality. The primary risk factor implicated in gastric cancer development is infection with Helicobacter pylori. H. pylori induces chronic inflammation affecting the gastric epithelium, which can lead to DNA damage and the promotion of precancerous lesions. Disease manifestations associated with H. pylori are attributed to virulence factors with multiple activities, and its capacity to subvert host immunity. One of the most significant H. pylori virulence determinants is the cagPAI gene cluster, which encodes a type IV secretion system and the CagA toxin. This secretion system allows H. pylori to inject the CagA oncoprotein into host cells, causing multiple cellular perturbations. Despite the high prevalence of H. pylori infection, only a small percentage of affected individuals develop significant clinical outcomes, while most remain asymptomatic. Therefore, understanding how H. pylori triggers carcinogenesis and its immune evasion mechanisms is critical in preventing gastric cancer and mitigating the burden of this life-threatening disease. This review aims to provide an overview of our current understanding of H. pylori infection, its association with gastric cancer and other gastric diseases, and how it subverts the host immune system to establish persistent infection.
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Affiliation(s)
- Victor E Reyes
- Department of Pediatrics and Microbiology & Immunology, University of Texas Medical Branch, 301 University Blvd., Galveston, TX 77555-0372, USA
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8
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Beccaceci G, Sigal M. Unwelcome guests - the role of gland-associated Helicobacter pylori infection in gastric carcinogenesis. Front Oncol 2023; 13:1171003. [PMID: 37152042 PMCID: PMC10160455 DOI: 10.3389/fonc.2023.1171003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Accepted: 04/04/2023] [Indexed: 05/09/2023] Open
Abstract
Helicobacter pylori (H. pylori) are Gram-negative bacteria that cause chronic gastritis and are considered the main risk factor for the development of gastric cancer. H. pylori have evolved to survive the harsh luminal environment of the stomach and are known to cause damage and signaling aberrations in gastric epithelial cells, which can result in premalignant and malignant pathology. As well as colonizing the gastric mucus and surface epithelial cells, a subpopulation of H. pylori can invade deep into the gastric glands and directly interact with progenitor and stem cells. Gland colonization therefore bears the potential to cause direct injury to long-lived cells. Moreover, this bacterial subpopulation triggers a series of host responses that cause an enhanced proliferation of stem cells. Here, we review recent insights into how gastric gland colonization by H. pylori is established, the resulting pro-carcinogenic epithelial signaling alterations, as well as new insights into stem cell responses to infection. Together these point towards a critical role of gland-associated H. pylori in the development of gastric cancer.
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Affiliation(s)
- Giulia Beccaceci
- Medical Department, Division of Gastroenterology and Hepatology, Charité-Universtitätsmedizin Berlin, Berlin, Germany
- The Berlin Institute for Medical Systems Biology (BIMSB), Max Delbrück Center for Molecular Medicine, Berlin, Germany
| | - Michael Sigal
- Medical Department, Division of Gastroenterology and Hepatology, Charité-Universtitätsmedizin Berlin, Berlin, Germany
- The Berlin Institute for Medical Systems Biology (BIMSB), Max Delbrück Center for Molecular Medicine, Berlin, Germany
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9
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Waguia Kontchou C, Häcker G. Role of mitochondrial outer membrane permeabilization during bacterial infection. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2023; 374:83-127. [PMID: 36858657 DOI: 10.1016/bs.ircmb.2022.10.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Beyond the initial 'powerhouse' view, mitochondria have numerous functions in their mammalian cell and contribute to many physiological processes, and many of these we understand only partially. The control of apoptosis by mitochondria is firmly established. Many questions remain however how this function is embedded into physiology, and how other signaling pathways regulate mitochondrial apoptosis; the interplay of bacteria with the mitochondrial apoptosis pathway is one such example. The outer mitochondrial membrane regulates both import into mitochondria and the release of intermembrane, and in some situations also matrix components from mitochondria, and these mitochondrial components can have signaling function in the cytosol. One function is the induction of apoptotic cell death. An exciting, more recently discovered function is the regulation of inflammation. Mitochondrial molecules, both proteins and nucleic acids, have inflammatory activity when released from mitochondria, an activity whose regulation is intertwined with the activation of apoptotic caspases. Bacterial infection can have more general effects on mitochondrial apoptosis-regulation, through effects on host transcription and other pathways, such as signals controlled by pattern recognition. Some specialized bacteria have products that more specifically regulate signaling to the outer mitochondrial membrane, and to apoptosis; both pro- and anti-apoptotic mechanisms have been reported. Among the intriguing recent findings in this area are signaling contributions of porins and the sub-lethal release of intermembrane constituents. We will here review the literature and place the new developments into the established context of mitochondrial signaling during the contact of bacterial pathogens with human cells.
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Affiliation(s)
- Collins Waguia Kontchou
- Institute of Medical Microbiology and Hygiene, Medical Center-University of Freiburg, Faculty of Medicine, Freiburg, Germany
| | - Georg Häcker
- Institute of Medical Microbiology and Hygiene, Medical Center-University of Freiburg, Faculty of Medicine, Freiburg, Germany; BIOSS Centre for Biological Signalling Studies, University of Freiburg, Freiburg, Germany.
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10
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Humic substances from composted fennel residues control the inflammation induced by Helicobacter pylori infection in AGS cells. PLoS One 2023; 18:e0281631. [PMID: 36893132 PMCID: PMC9997894 DOI: 10.1371/journal.pone.0281631] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2022] [Accepted: 01/28/2023] [Indexed: 03/10/2023] Open
Abstract
Helicobacter pylori (H. pylori) is a common human pathogen causing inflammation. Recent studies have suggested a sophisticated interplay between mitochondria, innate immunity and inflammatory response, thus proposing mitochondrial disfunction as the hallmark of severe inflammatory disorders. In this study, humic substances isolated from composted fennel residues (HS-FEN) were tested as potential therapeutical strategy to restore the mitochondrial physiology and control the inflammation associated with H. pylori infection. The molecular features of HS-FEN were characterized by infrared spectrometry, thermochemolysis-GC/MS, NMR spectroscopy, and high-performance size-exclusion chromatography (HPSEC), which revealed the presence of aromatic polyphenolic components arranged in a rather stable conformation. In vitro results showed antioxidant and anti-inflammatory properties of HS-FEN, that was found to increase the expression level of OPA-1 and SOD-2 genes and in AGS cells stimulated with H. pylori culture filtrate (Hpcf) and concomitantly decrease the expression level of Drp-1 gene and IL-12, IL-17 and G-CSF proteins. The hydrophobic features of HS, their conformational arrangement and large content of bioactive molecules may explain the beneficial effects of HS-FEN, that may potentially become an interesting source of anti-inflammatory agents capable to counteract or prevent the H. pylori-related inflammatory disorders.
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11
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Torres J, Touati E. Mitochondrial Function in Health and Disease: Responses to Helicobacter pylori Metabolism and Impact in Gastric Cancer Development. Curr Top Microbiol Immunol 2023; 444:53-81. [PMID: 38231215 DOI: 10.1007/978-3-031-47331-9_3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2024]
Abstract
Mitochondria are major cellular organelles that play an essential role in metabolism, stress response, immunity, and cell fate. Mitochondria are organized in a network with other cellular compartments, functioning as a signaling hub to maintain cells' health. Mitochondrial dysfunctions and genome alterations are associated with diseases including cancer. Mitochondria are a preferential target for pathogens, which have developed various mechanisms to hijack cellular functions for their benefit. Helicobacter pylori is recognized as the major risk factor for gastric cancer development. H. pylori induces oxidative stress and chronic gastric inflammation associated with mitochondrial dysfunction. Its pro-apoptotic cytotoxin VacA interacts with the mitochondrial inner membrane, leading to increased permeability and decreased ATP production. Furthermore, H. pylori induces mitochondrial DNA damage and mutation, concomitant with the development of gastric intraepithelial neoplasia as observed in infected mice. In this chapter, we present diverse aspects of the role of mitochondria as energy supplier and signaling hubs and their adaptation to stress conditions. The metabolic activity of mitochondria is directly linked to biosynthetic pathways. While H. pylori virulence factors and derived metabolites are essential for gastric colonization and niche adaptation, they may also impact mitochondrial function and metabolism, and may have consequences in gastric pathogenesis. Importantly, during its long way to reach the gastric epithelium, H. pylori faces various cellular types along the gastric mucosa. We discuss how the mitochondrial response of these different cells is affected by H. pylori and impacts the colonization and bacterium niche adaptation and point to areas that remain to be investigated.
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Affiliation(s)
- Javier Torres
- Unidad de Investigacion en Enfermedades Infecciosas, UMAE Pediatriıa, Instituto Mexicano del Seguro Social, Ciudad de Mexico, Mexico
| | - Eliette Touati
- Equipe DMic01-Infection, Génotoxicité et Cancer, Département de Microbiologie, UMR CNRS 6047, Institut Pasteur, Université Paris Cité, F-75015, Paris, France.
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12
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Naumann M, Ferino L, Sharafutdinov I, Backert S. Gastric Epithelial Barrier Disruption, Inflammation and Oncogenic Signal Transduction by Helicobacter pylori. Curr Top Microbiol Immunol 2023; 444:207-238. [PMID: 38231220 DOI: 10.1007/978-3-031-47331-9_8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2024]
Abstract
Helicobacter pylori exemplifies one of the most favourable bacterial pathogens worldwide. The bacterium colonizes the gastric mucosa in about half of the human population and constitutes a major risk factor for triggering gastric diseases such as stomach cancer. H. pylori infection represents a prime example of chronic inflammation and cancer-inducing bacterial pathogens. The microbe utilizes a remarkable set of virulence factors and strategies to control cellular checkpoints of inflammation and oncogenic signal transduction. This chapter emphasizes on the pathogenicity determinants of H. pylori such as the cytotoxin-associated genes pathogenicity island (cagPAI)-encoded type-IV secretion system (T4SS), effector protein CagA, lipopolysaccharide (LPS) metabolite ADP-glycero-β-D-manno-heptose (ADP-heptose), cytotoxin VacA, serine protease HtrA, and urease, and how they manipulate various key host cell signaling networks in the gastric epithelium. In particular, we highlight the H. pylori-induced disruption of cell-to-cell junctions, pro-inflammatory activities, as well as proliferative, pro-apoptotic and anti-apoptotic responses. Here we review these hijacked signal transduction events and their impact on gastric disease development.
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Affiliation(s)
- Michael Naumann
- Institute of Experimental Internal Medicine, Medical Faculty, Otto Von Guericke University, Leipziger Str. 44, 39120, Magdeburg, Germany.
| | - Lorena Ferino
- Institute of Experimental Internal Medicine, Medical Faculty, Otto Von Guericke University, Leipziger Str. 44, 39120, Magdeburg, Germany
| | - Irshad Sharafutdinov
- Dept. Biology, Division of Microbiology, Friedrich-Alexander-Universität Erlangen-Nürnberg, Staudtstr. 5, 91058, Erlangen, Germany
| | - Steffen Backert
- Dept. Biology, Division of Microbiology, Friedrich-Alexander-Universität Erlangen-Nürnberg, Staudtstr. 5, 91058, Erlangen, Germany.
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13
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Chen G, Tan Z, Liu Y, Weng T, Xia L, Lu Y. Function and Characterization of an Alanine Dehydrogenase Homolog From Nocardia seriolae. Front Vet Sci 2022; 8:801990. [PMID: 35097049 PMCID: PMC8790279 DOI: 10.3389/fvets.2021.801990] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Accepted: 11/22/2021] [Indexed: 01/05/2023] Open
Abstract
Fish nocardiosis is a chronic, systemic, granulomatous disease in aquaculture. Nocardia seriolae has been reported to be one of the main pathogenic bacteria of fish nocardiosis. There are few studies on the associated virulence factors and pathogenesis of N. seriolae. Alanine dehydrogenase (ALD), which may be a secreted protein, was discovered by analysis using bioinformatics methods throughout the whole genomic sequence of N. seriolae. Nevertheless, the roles of ALD and its homologs in the pathogenesis of N. seriolae are not demonstrated. In this study, the function of N. seriolae ALD (NsALD) was preliminarily investigated by gene cloning, host cell subcellular localization, secreted protein identification, and cell apoptosis detection. Identification of the extracellular products of N. seriolae via mass spectrometry (MS) analysis revealed that NsALD is a secreted protein. In addition, subcellular localization of NsALD-GFP recombinant protein in fathead minnow (FHM) cells showed that the strong green fluorescence co-localized with the mitochondria. Moreover, apoptosis assays demonstrated that the overexpression of NsALD induces apoptosis in FHM cells. This study may lay the foundation for further exploration of the function of NsALD and facilitate further understanding of the pathogenic mechanism and the associated virulence factors of N. seriolae.
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Affiliation(s)
- Guoquan Chen
- Guangdong Provincial Key Laboratory of Pathogenic Biology and Epidemiology for Aquatic Economic Animals, Fisheries College of Guangdong Ocean University, Zhanjiang, China
- Guangdong Provincial Engineering Research Center for Aquatic Animal Health Assessment, Shenzhen Public Service Platform for Evaluation of Marine Economic Animal Seedings, Shenzhen Institute of Guangdong Ocean University, Shenzhen, China
| | - Ziyang Tan
- Guangdong Provincial Key Laboratory of Pathogenic Biology and Epidemiology for Aquatic Economic Animals, Fisheries College of Guangdong Ocean University, Zhanjiang, China
| | - Yansheng Liu
- Guangdong Provincial Key Laboratory of Pathogenic Biology and Epidemiology for Aquatic Economic Animals, Fisheries College of Guangdong Ocean University, Zhanjiang, China
- Guangdong Provincial Engineering Research Center for Aquatic Animal Health Assessment, Shenzhen Public Service Platform for Evaluation of Marine Economic Animal Seedings, Shenzhen Institute of Guangdong Ocean University, Shenzhen, China
| | - Tingting Weng
- Guangdong Provincial Key Laboratory of Pathogenic Biology and Epidemiology for Aquatic Economic Animals, Fisheries College of Guangdong Ocean University, Zhanjiang, China
- Guangdong Provincial Engineering Research Center for Aquatic Animal Health Assessment, Shenzhen Public Service Platform for Evaluation of Marine Economic Animal Seedings, Shenzhen Institute of Guangdong Ocean University, Shenzhen, China
| | - Liqun Xia
- Guangdong Provincial Key Laboratory of Pathogenic Biology and Epidemiology for Aquatic Economic Animals, Fisheries College of Guangdong Ocean University, Zhanjiang, China
- Guangdong Provincial Engineering Research Center for Aquatic Animal Health Assessment, Shenzhen Public Service Platform for Evaluation of Marine Economic Animal Seedings, Shenzhen Institute of Guangdong Ocean University, Shenzhen, China
- *Correspondence: Liqun Xia
| | - Yishan Lu
- Guangdong Provincial Key Laboratory of Pathogenic Biology and Epidemiology for Aquatic Economic Animals, Fisheries College of Guangdong Ocean University, Zhanjiang, China
- Guangdong Provincial Engineering Research Center for Aquatic Animal Health Assessment, Shenzhen Public Service Platform for Evaluation of Marine Economic Animal Seedings, Shenzhen Institute of Guangdong Ocean University, Shenzhen, China
- Yishan Lu
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14
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Abstract
The intimate involvement of pathogens with the heightened risk for developing certain cancers is an area of research that has captured a great deal of attention over the last 10 years. One firmly established paradigm that highlights this aspect of disease progression is in the instance of Helicobacter pylori infection and the contribution it makes in elevating the risk for developing gastric cancer. Whilst the molecular mechanisms that pinpoint the contribution that this microorganism inflicts towards host cells during gastric cancer initiation have come into greater focus, another picture that has also emerged is one that implicates the host's immune system, and the chronic inflammation that can arise therefrom, as being a central contributory factor in disease progression. Consequently, when taken with the underlying role that the extracellular matrix plays in the development of most cancers, and how this dynamic can be modulated by proteases expressed from the tumor or inflammatory cells, a complex and detailed relationship shared between the individual cellular components and their surroundings is coming into focus. In this review article, we draw attention to the emerging role played by the cathepsin proteases in modulating the stage-specific progression of Helicobacter pylori-initiated gastric cancer and the underlying immune response, while highlighting the therapeutic significance of this dynamic and how it may be amenable for novel intervention strategies within a basic research or clinical setting.
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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:pathogens11010003. [PMID: 35055951 PMCID: PMC8777890 DOI: 10.3390/pathogens11010003] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [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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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:ijms22083942. [PMID: 33920443 PMCID: PMC8069053 DOI: 10.3390/ijms22083942] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [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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Liu XZ, Zhang YM, Jia NY, Zhang H. Helicobacter pylori infection is associated with elevated galactose-deficient IgA1 in IgA nephropathy. Ren Fail 2020; 42:539-546. [PMID: 32524871 PMCID: PMC7946026 DOI: 10.1080/0886022x.2020.1772295] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2020] [Revised: 05/14/2020] [Accepted: 05/14/2020] [Indexed: 02/07/2023] Open
Abstract
Background: Mucosal immunity plays an important role in the pathogenesis of IgA nephropathy (IgAN). This study aimed to investigate if infection of Helicobacter pylori (H. pylori), a common bacteria in the gastrointestinal tract, associated with IgAN.Methods: This study included 261 patients with IgAN and 46 healthy controls. Clinical information and plasma samples were collected from patients and healthy controls. H. pylori infection was confirmed by western blot. Plasma IgA1 and galactose-deficient IgA1 (Gd-IgA1) levels were detected by specific enzyme-linked immunosorbent assay.Results: Total H. pylori infection rates showed no statistical differences between IgAN patients and healthy controls, but the infection rates of type I H. pylori in IgAN patients were significantly higher than those in healthy controls (44.4 vs. 28.3%, p = 0.040). Compared with uninfected patients, the systolic blood pressure, 24-h proteinuria, and blood urea nitrogen levels were significantly higher in patients with H. pylori infection (126.0 ± 15.5 vs. 119.6 ± 14.5 mmHg, p = 0.010; 1.8 ± 2.7 vs. 1.2 ± 1.4 g/24h, p = 0.013; 7.9 ± 5.4 vs. 6.7 ± 3.9 μmol/L, p = 0.042), especially in patients with type I infection (126.5 ± 15.4 vs. 119.6 ± 14.5 mmHg, p = 0.002; 1.9 ± 2.9 vs. 1.2 ± 1.4 g/24 h, p = 0.033; 8.1 ± 5.6 vs. 6.7 ± 3.9 μmol/L, p = 0.041). Similarly, patients with IgAN and type I H. pylori infection showed higher plasma Gd-IgA1 levels than uninfected patients (5.5 ± 2.2 vs. 4.5 ± 2.2 μg/mL, p = 0.037).Conclusions: Virulent type I H. pylori infection is more common in patients with IgAN. Patients with IgAN and type I H. pylori infection showed lower renal function and higher underglycosylation of plasma IgA1.
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Affiliation(s)
- Xing-Zi Liu
- Renal Division, Peking University First Hospital, Peking University Institute of Nephrology, Beijing, People’s Republic of China
- Key Laboratory of Renal Disease, Ministry of Health of China, Key Laboratory of Chronic Kidney Disease Prevention and Treatment (Peking University), Ministry of Education, Beijing, People’s Republic of China
| | - Yue-Miao Zhang
- Renal Division, Peking University First Hospital, Peking University Institute of Nephrology, Beijing, People’s Republic of China
- Key Laboratory of Renal Disease, Ministry of Health of China, Key Laboratory of Chronic Kidney Disease Prevention and Treatment (Peking University), Ministry of Education, Beijing, People’s Republic of China
| | - Ni-Ya Jia
- Renal Division, Peking University First Hospital, Peking University Institute of Nephrology, Beijing, People’s Republic of China
- Key Laboratory of Renal Disease, Ministry of Health of China, Key Laboratory of Chronic Kidney Disease Prevention and Treatment (Peking University), Ministry of Education, Beijing, People’s Republic of China
| | - Hong Zhang
- Renal Division, Peking University First Hospital, Peking University Institute of Nephrology, Beijing, People’s Republic of China
- Key Laboratory of Renal Disease, Ministry of Health of China, Key Laboratory of Chronic Kidney Disease Prevention and Treatment (Peking University), Ministry of Education, Beijing, People’s Republic of China
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Helicobacter pylori-Derived Outer Membrane Vesicles (OMVs): Role in Bacterial Pathogenesis? Microorganisms 2020; 8:microorganisms8091328. [PMID: 32878302 PMCID: PMC7564109 DOI: 10.3390/microorganisms8091328] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [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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Boquet P. In Memoriam to Vittorio Ricci, Professor of Pathology at Pavia University. Toxins (Basel) 2020; 12:toxins12060401. [PMID: 32560515 PMCID: PMC7354507 DOI: 10.3390/toxins12060401] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Accepted: 06/11/2020] [Indexed: 11/30/2022] Open
Affiliation(s)
- Patrice Boquet
- Department of Clinical Bacteriology, Nice University Hospital, 151 Route St Antoine de Ginestiere, 06202 Nice, France
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20
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Yang JY, Kim P, Jeong SH, Lee SW, Myung YS, Baeg MK, Kim JB. The Effects of Sulglycotide on the Adhesion and the Inflammation of Helicobacter Pylori. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2020; 17:E2918. [PMID: 32340212 PMCID: PMC7215434 DOI: 10.3390/ijerph17082918] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Accepted: 04/23/2020] [Indexed: 01/05/2023]
Abstract
Helicobacter pylori (H. pylori) is a primary etiologic factor in gastric diseases. Sulglycotide is a glycopeptide derived from pig duodenal mucin. Esterification of its carbohydrate chains with sulfate groups creates a potent gastroprotective agent used to treat various gastric diseases. We investigated the inhibitory effects of sulglycotide on adhesion and inflammation after H. pylori infection in human gastric adenocarcinoma cells (AGS cells). H. pylori reference strain 60190 (ATCC 49503) was cultured on Brucella agar supplemented with 10% bovine serum. Sulgylcotide-mediated growth inhibition of H. pylori was evaluated using the broth dilution method. Inhibition of H. pylori adhesion to AGS cells by sulglycotide was assessed using a urease assay. Effects of sulglycotide on the translocation of virulence factors was measured using western blot to detect cytotoxin-associated protein A (CagA) and vacuolating cytotoxin A (VacA) proteins. Inhibition of IL-8 secretion was measured using enzyme-linked immunosorbent assay (ELISA) to determine the effects of sulglycotide on inflammation. Sulglycotide did not inhibit the growth of H. pylori, however, after six and 12 hours of infection on AGS cells, H. pylori adhesion was significantly inhibited by approximately 60% by various concentrations of sulglycotide. Sulglycotide decreased H. pylori virulence factor (CagA and VacA) translocation to AGS cells and inhibited IL-8 secretion. Sulglycotide inhibited H. pylori adhesion and inflammation after infection of AGS cells in vitro. These results support the use of sulglycotide to treat H. pylori infections.
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Affiliation(s)
- Ji Yeong Yang
- Department of Biomedical Laboratory Science, College of Health Sciences, Yonsei University, Wonju 26493, Korea;
| | - Pumsoo Kim
- Division of Gastroenterology, Department of Internal Medicine, Catholic Kwandong University International St. Mary’s Hospital, Incheon 22711, Korea; (P.K.); (Y.S.M.); (M.K.B.)
| | - Seok-Hoo Jeong
- Division of Gastroenterology, Department of Internal Medicine, Catholic Kwandong University International St. Mary’s Hospital, Incheon 22711, Korea; (P.K.); (Y.S.M.); (M.K.B.)
| | | | - Yu Sik Myung
- Division of Gastroenterology, Department of Internal Medicine, Catholic Kwandong University International St. Mary’s Hospital, Incheon 22711, Korea; (P.K.); (Y.S.M.); (M.K.B.)
| | - Myong Ki Baeg
- Division of Gastroenterology, Department of Internal Medicine, Catholic Kwandong University International St. Mary’s Hospital, Incheon 22711, Korea; (P.K.); (Y.S.M.); (M.K.B.)
| | - Jong-Bae Kim
- Department of Biomedical Laboratory Science, College of Health Sciences, Yonsei University, Wonju 26493, Korea;
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Guillermo Espinoza-Contreras J, Idalia Torres-Ruiz M, Ariel Waller-González L, De Jesús Ramírez-García J, Torres-López J, Ventura-Juárez J, Verónica Moreno-Córdova E, Ernesto López-Ramos J, Humberto Muñoz-Ortega M, Eugenia Vargas-Camaño M, González-Segovia R. Immunological markers and Helicobacter pylori in patients with stomach cancer: Expression and correlation. Biomed Rep 2020; 12:233-243. [PMID: 32257186 PMCID: PMC7100142 DOI: 10.3892/br.2020.1285] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Accepted: 01/17/2020] [Indexed: 01/22/2023] Open
Abstract
Programmed death-ligand 1 (PD-L1) and ICOS-L (also referred to as B7 homolog 1 and 2, respectively) modulate the immune inflammatory response. The aim of the present study was to examine the expression levels of these inflammatory mediators in two groups of patients with an Helicobacter pylori (H. pylori) infection; patients with and without gastric cancer. The association between bacterial virulence factors, CagA and VacA, was also examined, as well as their correlation with the inflammatory profile. Endoscopy analysis indicated that 18 patients suffered from cancer and 28 patients suffered from other gastric pathologies. PCR and reverse transcription-quantitative PCR were used to analyze gastric biopsies and determine the expression levels of the inflammatory modulators PD-L1 and ICOS-L, transcription factors, cytokines and other genes associated with inflammation and pathogenicity. All 46 patients were determined positive for markers of H. pylori. Patients with stomach cancer had lower levels of ICOS-L (P<0.05) and GATA3 (P<0.01), a negative correlation between CagA and IL-17 (P<0.05), a positive correlation between CagA and IL-10 (P<0.05), a negative correlation between vacA-m1 and retinoid orphan receptor γt (RORγt) (P<0.001), and a positive correlation between RORγt and ICOS-L (P<0.001). The reduced levels of ICOS-L and GATA3 along with the negative correlation between CagA and IL-17, and between vacA-m1 and RORγt were all associated with an increased risk of gastric cancer in the present cohort.
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Affiliation(s)
| | - Miriam Idalia Torres-Ruiz
- Departamento de Endoscopia, Centro Médico Nacional 20 de Noviembre ISSSTE, Ciudad de México, CP 03229, México
| | - Luis Ariel Waller-González
- Departamento de Endoscopia, Centro Médico Nacional 20 de Noviembre ISSSTE, Ciudad de México, CP 03229, México
| | | | - Javier Torres-López
- Unidad de Investigación Médica en Enfermedades Infecciosas y Parasitarias UMAE, Hospital de Pediatría, IMSS, Ciudad de México, CP 06720, México
| | - Javier Ventura-Juárez
- Departamento de Morfología, Universidad Autónoma de Aguascalientes, Aguascalientes Ags, CP 20131, México
| | | | - Juan Ernesto López-Ramos
- Departamento de Microbiología, Universidad Autónoma de Aguascalientes, Aguascalientes Ags, CP 20131, México
| | | | - María Eugenia Vargas-Camaño
- Servicio de Inmunología Clínica y Alergía, Centro Médico Nacional 20 Noviembre ISSSTE, Ciudad de México, CP 03229, México
| | - Rodolfo González-Segovia
- Departamento de Microbiología, Universidad Autónoma de Aguascalientes, Aguascalientes Ags, CP 20131, México
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Toracchio S, Caruso RA, Perconti S, Rigoli L, Betri E, Neri M, Verginelli F, Mariani-Costantini R. Evolutionarily-Related Helicobacter pylori Genotypes and Gastric Intraepithelial Neoplasia in a High-Risk Area of Northern Italy. Microorganisms 2020; 8:microorganisms8030324. [PMID: 32110918 PMCID: PMC7142731 DOI: 10.3390/microorganisms8030324] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2020] [Revised: 02/22/2020] [Accepted: 02/24/2020] [Indexed: 01/11/2023] Open
Abstract
Helicobacter pylori (Hp) is the major recognized risk factor for non-cardia gastric cancer (GC), but only a fraction of infected subjects develop GC, thus GC risk might reflect other genetic/environmental cofactors and/or differences in virulence among infectious Hp strains. Focusing on a high GC risk area of Northern Italy (Cremona, Lombardy) and using archived paraffin-embedded biopsies, we investigated the associations between the Hp vacA and cagA genotype variants and gastric intraepithelial neoplasia (GIN, 33 cases) versus non-neoplastic gastroduodenal lesions (NNGDLs, 37 cases). The glmM gene and the cagA and vacA (s and m) genotypes were determined by polymerase chain reaction (PCR) and sequencing. Hp was confirmed in 37/37 (100%) NNGDLs and detected in 9/33 GINs (27%), consistently with the well-known Hp loss in GC. CagA was detected in 4/9 Hp-positive GINs and in 29/37 NNGDLs. The vacA s1a and m1 subtypes were more common in GINs than in NNGDLs (6/7 vs. 12/34, p=0.014, for s1a; 7/7 vs. 18/34, p=0.020 for m1), with significant vacA s genotype-specific variance. The GIN-associated vacA s1a sequences clustered together, suggesting that aggressive Hp strains from a unique founder contribute to GC in the high-risk area studied.
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Affiliation(s)
- Sonia Toracchio
- Center for Advanced Studies (CAST/CeSI-MeT), “G. d’Annunzio” University of Chieti-Pescara, 66100 Chieti, Italy; (S.T.); (S.P.); (M.N.)
| | - Rosario Alberto Caruso
- Department of Human Pathology in Adult and Developmental Age “Gaetano Barresi”, Section of Pathology, University of Messina, 98123 Messina, Italy; (R.A.C.); (L.R.)
| | - Silvia Perconti
- Center for Advanced Studies (CAST/CeSI-MeT), “G. d’Annunzio” University of Chieti-Pescara, 66100 Chieti, Italy; (S.T.); (S.P.); (M.N.)
- Department of Medical, Oral and Biotechnological Sciences, “G. d’Annunzio” University of Chieti-Pescara, 66100 Chieti, Italy
| | - Luciana Rigoli
- Department of Human Pathology in Adult and Developmental Age “Gaetano Barresi”, Section of Pathology, University of Messina, 98123 Messina, Italy; (R.A.C.); (L.R.)
| | - Enrico Betri
- Department of Pathology, Istituti Ospitalieri, 26100 Cremona, Italy;
| | - Matteo Neri
- Center for Advanced Studies (CAST/CeSI-MeT), “G. d’Annunzio” University of Chieti-Pescara, 66100 Chieti, Italy; (S.T.); (S.P.); (M.N.)
- Department of Medicine and Aging Science, “G. d’Annunzio” University of Chieti-Pescara, 66100 Chieti, Italy
| | - Fabio Verginelli
- Center for Advanced Studies (CAST/CeSI-MeT), “G. d’Annunzio” University of Chieti-Pescara, 66100 Chieti, Italy; (S.T.); (S.P.); (M.N.)
- Department of Pharmacy, G. d’Annunzio University of Chieti-Pescara, 66100 Chieti, Italy
- Correspondence: (F.V.); (R.M.-C.); Tel.: +39-08713554576 (F.V.); +39-0871541496 (R.M.-C.)
| | - Renato Mariani-Costantini
- Center for Advanced Studies (CAST/CeSI-MeT), “G. d’Annunzio” University of Chieti-Pescara, 66100 Chieti, Italy; (S.T.); (S.P.); (M.N.)
- Department of Medical, Oral and Biotechnological Sciences, “G. d’Annunzio” University of Chieti-Pescara, 66100 Chieti, Italy
- Correspondence: (F.V.); (R.M.-C.); Tel.: +39-08713554576 (F.V.); +39-0871541496 (R.M.-C.)
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Tiku V, Tan MW, Dikic I. Mitochondrial Functions in Infection and Immunity. Trends Cell Biol 2020; 30:263-275. [PMID: 32200805 PMCID: PMC7126537 DOI: 10.1016/j.tcb.2020.01.006] [Citation(s) in RCA: 193] [Impact Index Per Article: 48.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2019] [Revised: 01/16/2020] [Accepted: 01/17/2020] [Indexed: 12/21/2022]
Abstract
Mitochondria have a central role in regulating a range of cellular activities and host responses upon bacterial infection. Multiple pathogens affect mitochondria dynamics and functions to influence their intracellular survival or evade host immunity. On the other side, major host responses elicited against infections are directly dependent on mitochondrial functions, thus placing mitochondria centrally in maintaining homeostasis upon infection. In this review, we summarize how different bacteria and viruses impact morphological and functional changes in host mitochondria and how this manipulation can influence microbial pathogenesis as well as the host cell metabolism and immune responses. Bacteria and viruses have evolved specific ways of targeting mitochondria to perturb mitochondrial function that can prove to be beneficial for these microbes. Many bacteria and viruses use specific virulence mechanisms to modulate mitochondrial dynamics, leading to either mitochondrial fusion or fission. Mitochondrial metabolism can also be impacted by bacterial and viral infections. While in some cases bacteria and viruses induce the mitochondrial cell death pathway, in others cell death is inhibited promoting intracellular bacterial and viral proliferation. Mitochondria regulate different innate immune signaling pathways induced upon bacterial or viral infections.
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Affiliation(s)
- Varnesh Tiku
- Department of Infectious Diseases, Genentech Inc, South San Francisco, USA
| | - Man-Wah Tan
- Department of Infectious Diseases, Genentech Inc, South San Francisco, USA.
| | - Ivan Dikic
- Department of Infectious Diseases, Genentech Inc, South San Francisco, USA; Institute for Biochemistry II. Goethe University Clinic, Frankfurt, Germany.
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Hanafiah A, Lopes BS. Genetic diversity and virulence characteristics of Helicobacter pylori isolates in different human ethnic groups. INFECTION GENETICS AND EVOLUTION 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] [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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25
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Brito C, Cabanes D, Sarmento Mesquita F, Sousa S. Mechanisms protecting host cells against bacterial pore-forming toxins. Cell Mol Life Sci 2019; 76:1319-1339. [PMID: 30591958 PMCID: PMC6420883 DOI: 10.1007/s00018-018-2992-8] [Citation(s) in RCA: 88] [Impact Index Per Article: 17.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2018] [Revised: 12/06/2018] [Accepted: 12/10/2018] [Indexed: 12/19/2022]
Abstract
Pore-forming toxins (PFTs) are key virulence determinants produced and secreted by a variety of human bacterial pathogens. They disrupt the plasma membrane (PM) by generating stable protein pores, which allow uncontrolled exchanges between the extracellular and intracellular milieus, dramatically disturbing cellular homeostasis. In recent years, many advances were made regarding the characterization of conserved repair mechanisms that allow eukaryotic cells to recover from mechanical disruption of the PM membrane. However, the specificities of the cell recovery pathways that protect host cells against PFT-induced damage remain remarkably elusive. During bacterial infections, the coordinated action of such cell recovery processes defines the outcome of infected cells and is, thus, critical for our understanding of bacterial pathogenesis. Here, we review the cellular pathways reported to be involved in the response to bacterial PFTs and discuss their impact in single-cell recovery and infection.
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Affiliation(s)
- Cláudia Brito
- i3S-Instituto de Investigação e Inovação em Saúde, IBMC, Universidade do Porto, Rua Alfredo Allen, 208, 4200-135, Porto, Portugal
- Programa Doutoral em Biologia Molecular e Celular (MCbiology), Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto, Rua Jorge de Viterbo Ferreira 228, 4050-313, Porto, Portugal
| | - Didier Cabanes
- i3S-Instituto de Investigação e Inovação em Saúde, IBMC, Universidade do Porto, Rua Alfredo Allen, 208, 4200-135, Porto, Portugal
| | - Francisco Sarmento Mesquita
- i3S-Instituto de Investigação e Inovação em Saúde, IBMC, Universidade do Porto, Rua Alfredo Allen, 208, 4200-135, Porto, Portugal.
- Global Health Institute, School of Life Science, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland.
| | - Sandra Sousa
- i3S-Instituto de Investigação e Inovação em Saúde, IBMC, Universidade do Porto, Rua Alfredo Allen, 208, 4200-135, Porto, Portugal.
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Intracellular Degradation of Helicobacter pylori VacA Toxin as a Determinant of Gastric Epithelial Cell Viability. Infect Immun 2019; 87:IAI.00783-18. [PMID: 30692181 DOI: 10.1128/iai.00783-18] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [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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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] [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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Chronic Infections: A Possible Scenario for Autophagy and Senescence Cross-Talk. Cells 2018; 7:cells7100162. [PMID: 30308990 PMCID: PMC6210027 DOI: 10.3390/cells7100162] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2018] [Revised: 10/04/2018] [Accepted: 10/07/2018] [Indexed: 02/07/2023] Open
Abstract
Multiple tissues and systems in the organism undergo modifications during aging due to an accumulation of damaged proteins, lipids, and genetic material. To counteract this process, the cells are equipped with specific mechanisms, such as autophagy and senescence. Particularly, the immune system undergoes a process called immunosenescence, giving rise to a chronic inflammatory status of the organism, with a decreased ability to counteract antigens. The obvious result of this process is a reduced defence capacity. Currently, there is evidence that some pathogens are able to accelerate the immunosenescence process for their own benefit. Although to date numerous reports show the autophagy–senescence relationship, or the connection between pathogens with autophagy or senescence, the link between the three actors remains unexplored. In this review, we have summarized current knowledge about important issues related to aging, senescence, and autophagy.
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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: 51] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [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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30
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Shapla UM, Raihan J, Islam A, Alam F, Solayman N, Gan SH, Hossen S, Khalil I. Propolis: The future therapy against Helicobacter pylori-mediated gastrointestinal diseases. J Appl Biomed 2018. [DOI: 10.1016/j.jab.2017.10.007] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
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31
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Necchi V, Sommi P, Vanoli A, Fiocca R, Ricci V, Solcia E. Natural history of Helicobacter pylori VacA toxin in human gastric epithelium in vivo: vacuoles and beyond. Sci Rep 2017; 7:14526. [PMID: 29109534 PMCID: PMC5673961 DOI: 10.1038/s41598-017-15204-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2017] [Accepted: 10/23/2017] [Indexed: 02/08/2023] Open
Abstract
Uptake, intracellular trafficking and pathologic effects of VacA toxin from Helicobacter pylori have been widely investigated in vitro. However, no systematic analysis investigated VacA intracellular distribution and fate in H. pylori-infected human gastric epithelium in vivo, using ultrastructural immunocytochemistry that combines precise toxin localization with analysis of the overall cell ultrastructure and intercompartimental/interorganellar relationships. By immunogold procedure, in this study we investigated gastric biopsies taken from dyspeptic patients to characterize the overall toxin’s journey inside human gastric epithelial cells in vivo. Endocytic pits were found to take up VacA at sites of bacterial adhesion, leading to a population of peripheral endosomes, which in deeper (juxtanuclear) cytoplasm enlarged and fused each other to form large VacA-containing vacuoles (VCVs). These directly opened into endoplasmic reticulum (ER) cisternae, which in turn enveloped mitochondria and contacted the Golgi apparatus. In all such organelles we found toxin molecules, often coupled with structural damage. These findings suggest direct toxin transfer from VCVs to other target organelles such as ER/Golgi and mitochondria. VacA-induced cytotoxic changes were associated with the appearance of auto(phago)lysosomes containing VacA, polyubiquitinated proteins, p62/SQSTM1 protein, cathepsin D, damaged mitochondria and bacterial remnants, thus leading to persistent cell accumulation of degradative products.
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Affiliation(s)
- Vittorio Necchi
- Department of Molecular Medicine, Pathologic Anatomy and Human Physiology Units, University of Pavia, Pavia, Italy.,Centro Grandi Strumenti, University of Pavia, Pavia, Italy
| | - Patrizia Sommi
- Department of Molecular Medicine, Pathologic Anatomy and Human Physiology Units, University of Pavia, Pavia, Italy
| | - Alessandro Vanoli
- Department of Molecular Medicine, Pathologic Anatomy and Human Physiology Units, University of Pavia, Pavia, Italy
| | - Roberto Fiocca
- Department of Surgical and Diagnostic Sciences, Pathology Unit, University of Genova and IRCCS S. Martino, Genova, Italy
| | - Vittorio Ricci
- Department of Molecular Medicine, Pathologic Anatomy and Human Physiology Units, University of Pavia, Pavia, Italy.
| | - Enrico Solcia
- Department of Molecular Medicine, Pathologic Anatomy and Human Physiology Units, University of Pavia, Pavia, Italy.,Pathologic Anatomy Service, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy
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32
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McClain MS, Beckett AC, Cover TL. Helicobacter pylori Vacuolating Toxin and Gastric Cancer. Toxins (Basel) 2017; 9:toxins9100316. [PMID: 29023421 PMCID: PMC5666363 DOI: 10.3390/toxins9100316] [Citation(s) in RCA: 97] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2017] [Revised: 10/03/2017] [Accepted: 10/05/2017] [Indexed: 12/13/2022] Open
Abstract
Helicobacter pylori VacA is a channel-forming toxin unrelated to other known bacterial toxins. Most H. pylori strains contain a vacA gene, but there is marked variation among strains in VacA toxin activity. This variation is attributable to strain-specific variations in VacA amino acid sequences, as well as variations in the levels of VacA transcription and secretion. In this review, we discuss epidemiologic studies showing an association between specific vacA allelic types and gastric cancer, as well as studies that have used animal models to investigate VacA activities relevant to gastric cancer. We also discuss the mechanisms by which VacA-induced cellular alterations may contribute to the pathogenesis of gastric cancer.
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Affiliation(s)
- Mark S McClain
- Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN 37232, USA.
| | - Amber C Beckett
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, TN 37232, USA.
| | - Timothy L Cover
- Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN 37232, USA.
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, TN 37232, USA.
- Veterans Affairs Tennessee Valley Healthcare System, Nashville, TN 37212, USA.
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33
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Al-Maleki AR, Loke MF, Lui SY, Ramli NSK, Khosravi Y, Ng CG, Venkatraman G, Goh KL, Ho B, Vadivelu J. Helicobacter pylori outer inflammatory protein A (OipA) suppresses apoptosis of AGS gastric cells in vitro. Cell Microbiol 2017; 19. [PMID: 28776327 DOI: 10.1111/cmi.12771] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2016] [Revised: 07/02/2017] [Accepted: 07/26/2017] [Indexed: 12/12/2022]
Abstract
Outer inflammatory protein A (OipA) is an important virulence factor associated with gastric cancer and ulcer development; however, the results have not been well established and turned out to be controversial. This study aims to elucidate the role of OipA in Helicobacter pylori infection using clinical strains harbouring oipA "on" and "off" motifs. Proteomics analysis was performed on AGS cell pre-infection and postinfection with H. pylori oipA "on" and "off" strains, using liquid chromatography/mass spectrometry. AGS apoptosis and cell cycle assays were performed. Moreover, expression of vacuolating cytotoxin A (VacA) was screened using Western blotting. AGS proteins that have been suggested previously to play a role or associated with gastric disease were down-regulated postinfection with oipA "off" strains comparing to oipA "on" strains. Furthermore, oipA "off" and ΔoipA cause higher level of AGS cells apoptosis and G0/G1 cell-cycle arrest than oipA "on" strains. Interestingly, deletion of oipA increased bacterial VacA production. The capability of H. pylori to induce apoptosis and suppress expression of proteins having roles in human disease in the absence of oipA suggests that strains not expressing OipA may be less virulent or may even be protective against carcinogenesis compared those expressing OipA. This potentially explains the higher incidence of gastric cancer in East Asia where oipA "on" strains predominates.
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Affiliation(s)
- Anis Rageh Al-Maleki
- Department of Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Mun Fai Loke
- Department of Medical Microbiology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia.,Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Sook Yin Lui
- Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Nur Siti Khadijah Ramli
- Department of Medical Microbiology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Yalda Khosravi
- Department of Medical Microbiology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Chow Goon Ng
- Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Gopinath Venkatraman
- Department of Medical Microbiology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Khean-Lee Goh
- Department of Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Bow Ho
- Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore.,Singapore Precision Medicine Centre Pte Ltd, Singapore, Singapore
| | - Jamuna Vadivelu
- Department of Medical Microbiology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
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34
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Floch P, Mégraud F, Lehours P. Helicobacter pylori Strains and Gastric MALT Lymphoma. Toxins (Basel) 2017; 9:toxins9040132. [PMID: 28397767 PMCID: PMC5408206 DOI: 10.3390/toxins9040132] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2017] [Revised: 03/27/2017] [Accepted: 04/03/2017] [Indexed: 02/07/2023] Open
Abstract
This article summarizes the main findings concerning Helicobacter pylori associated with gastric MALT lymphoma (GML). Considered together, GML strains based on their virulence factor profile appear to be less virulent than those associated with peptic ulcers or gastric adenocarcinoma. A particular Lewis antigen profile has been identified in GML strains and could represent an alternative adaptive mechanism to escape the host immune response thereby allowing continuous antigenic stimulation of infiltrating lymphocytes.
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Affiliation(s)
- Pauline Floch
- INSERM, Univ. Bordeaux, UMR1053 Bordeaux Research In Translational Oncology, BaRITOn, F-33000 Bordeaux, France.
| | - Francis Mégraud
- INSERM, Univ. Bordeaux, UMR1053 Bordeaux Research In Translational Oncology, BaRITOn, F-33000 Bordeaux, France.
| | - Philippe Lehours
- INSERM, Univ. Bordeaux, UMR1053 Bordeaux Research In Translational Oncology, BaRITOn, F-33000 Bordeaux, France.
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35
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Pyburn TM, Foegeding NJ, González-Rivera C, McDonald NA, Gould KL, Cover TL, Ohi MD. Structural organization of membrane-inserted hexamers formed by Helicobacter pylori VacA toxin. Mol Microbiol 2016; 102:22-36. [PMID: 27309820 PMCID: PMC5035229 DOI: 10.1111/mmi.13443] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/13/2016] [Indexed: 01/08/2023]
Abstract
Helicobacter pylori colonizes the human stomach and is a potential cause of peptic ulceration or gastric adenocarcinoma. H. pylori secretes a pore-forming toxin known as vacuolating cytotoxin A (VacA). The 88 kDa secreted VacA protein, composed of an N-terminal p33 domain and a C-terminal p55 domain, assembles into water-soluble oligomers. The structural organization of membrane-bound VacA has not been characterized in any detail and the role(s) of specific VacA domains in membrane binding and insertion are unclear. We show that membrane-bound VacA organizes into hexameric oligomers. Comparison of the two-dimensional averages of membrane-bound and soluble VacA hexamers generated using single particle electron microscopy reveals a structural difference in the central region of the oligomers (corresponding to the p33 domain), suggesting that membrane association triggers a structural change in the p33 domain. Analyses of the isolated p55 domain and VacA variants demonstrate that while the p55 domain can bind membranes, the p33 domain is required for membrane insertion. Surprisingly, neither VacA oligomerization nor the presence of putative transmembrane GXXXG repeats in the p33 domain is required for membrane insertion. These findings provide new insights into the process by which VacA binds and inserts into the lipid bilayer to form membrane channels.
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Affiliation(s)
- Tasia M Pyburn
- Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, TN, 37232
| | - Nora J Foegeding
- Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, TN, 37232
| | - Christian González-Rivera
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, TN, 37232
| | - Nathan A McDonald
- Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, TN, 37232
| | - Kathleen L Gould
- Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, TN, 37232
| | - Timothy L Cover
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, TN, 37232
- Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN, 37232
- Veterans Affairs Tennessee Valley Healthcare System, Nashville, TN, 37212
| | - Melanie D Ohi
- Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, TN, 37232.
- Center for Structural Biology, Vanderbilt University School of Medicine, Nashville, TN, 37232.
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Li Q, Liu J, Gong Y, Yuan Y. Serum VacA antibody is associated with risks of peptic ulcer and gastric cancer: A meta-analysis. Microb Pathog 2016; 99:220-228. [PMID: 27568203 DOI: 10.1016/j.micpath.2016.08.030] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2016] [Revised: 07/27/2016] [Accepted: 08/23/2016] [Indexed: 12/17/2022]
Abstract
BACKGROUND Increasing studies have investigated the relationship between the status of H. pylori vacA antibody and risks of peptic ulcer disease (PUD) and gastric cancer (GC). However, the results were controversial. The aim of this meta-analysis is to clarify whether serum vacA antibody is associated with risks of PUD and GC. METHODS Databases including PubMed, Embase, Web of knowledge, Wanfang, Chinese National Knowledge Infrastructure (CNKI), OVID, Karger and Scopus were systematically searched for potentially eligible literature. Odds ratios (OR) and their 95% confidence interval (CI) were adopted to assess the strength of association. RESULTS Serum VacA antibody was associated with increased risk of PUD compared with gastritis/functional dyspepsia (FD) (OR = 1.96, 95%CI = 1.56-2.46, P < 0.001). Serum VacA antibody was significantly associated with increased risk of gastric ulcer (GU) and duodenal ulcer (DU) compared with gastritis/FD (GU: OR = 1.64, 95%CI = 1.02-2.62, P = 0.042; DU: OR = 2.06, 95%CI = 1.50-2.84, P < 0.001, respectively). Significant increased risk of GC was found in serum VacA antibody positive subjects compared with serum VacA antibody negative individuals (OR = 2.78, 95%CI = 1.98-3.89, P < 0.001). There was no significant publication bias in all of the comparisons. CONCLUSIONS Serum VacA antibody was significantly associated with increased risks of peptic ulcer disease, gastric ulcer and duodenal ulcer compared with gastritis and functional dyspepsia controls. Significant association was also found between serum VacA antibody and gastric cancer risk. Serum VacA antibody might be a potential biomarker for the prediction of risks of PUD and GC.
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Affiliation(s)
- Qiuping Li
- Tumor Etiology and Screening Department of Cancer Institute and General Surgery, The First Affiliated Hospital of China Medical University, and Key Laboratory of Cancer Etiology and Prevention (China Medical University), Liaoning Provincial Education Department, Shenyang 110001, China
| | - Jingwei Liu
- Tumor Etiology and Screening Department of Cancer Institute and General Surgery, The First Affiliated Hospital of China Medical University, and Key Laboratory of Cancer Etiology and Prevention (China Medical University), Liaoning Provincial Education Department, Shenyang 110001, China
| | - Yuehua Gong
- Tumor Etiology and Screening Department of Cancer Institute and General Surgery, The First Affiliated Hospital of China Medical University, and Key Laboratory of Cancer Etiology and Prevention (China Medical University), Liaoning Provincial Education Department, Shenyang 110001, China.
| | - Yuan Yuan
- Tumor Etiology and Screening Department of Cancer Institute and General Surgery, The First Affiliated Hospital of China Medical University, and Key Laboratory of Cancer Etiology and Prevention (China Medical University), Liaoning Provincial Education Department, Shenyang 110001, China.
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A Nonoligomerizing Mutant Form of Helicobacter pylori VacA Allows Structural Analysis of the p33 Domain. Infect Immun 2016; 84:2662-70. [PMID: 27382020 PMCID: PMC4995914 DOI: 10.1128/iai.00254-16] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2016] [Accepted: 06/24/2016] [Indexed: 12/17/2022] Open
Abstract
Helicobacter pylori secretes a pore-forming VacA toxin that has structural features and activities substantially different from those of other known bacterial toxins. VacA can assemble into multiple types of water-soluble flower-shaped oligomeric structures, and most VacA activities are dependent on its capacity to oligomerize. The 88-kDa secreted VacA protein can undergo limited proteolysis to yield two domains, designated p33 and p55. The p33 domain is required for membrane channel formation and intracellular toxic activities, and the p55 domain has an important role in mediating VacA binding to cells. Previous studies showed that the p55 domain has a predominantly β-helical structure, but no structural data are available for the p33 domain. We report here the purification and analysis of a nonoligomerizing mutant form of VacA secreted by H. pylori The nonoligomerizing 88-kDa mutant protein retains the capacity to enter host cells but lacks detectable toxic activity. Analysis of crystals formed by the monomeric protein reveals that the β-helical structure of the p55 domain extends into the C-terminal portion of p33. Fitting the p88 structural model into an electron microscopy map of hexamers formed by wild-type VacA (predicted to be structurally similar to VacA membrane channels) reveals that p55 and the β-helical segment of p33 localize to peripheral arms but do not occupy the central region of the hexamers. We propose that the amino-terminal portion of p33 is unstructured when VacA is in a monomeric form and that it undergoes a conformational change during oligomer assembly.
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38
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Nair MRB, Chouhan D, Sen Gupta S, Chattopadhyay S. Fermented Foods: Are They Tasty Medicines for Helicobacter pylori Associated Peptic Ulcer and Gastric Cancer? Front Microbiol 2016; 7:1148. [PMID: 27504109 PMCID: PMC4958626 DOI: 10.3389/fmicb.2016.01148] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2016] [Accepted: 07/11/2016] [Indexed: 12/21/2022] Open
Abstract
More than a million people die every year due to gastric cancer and peptic ulcer. Helicobacter pylori infection in stomach is the most important reason for these diseases. Interestingly, only 10-20% of the H. pylori infected individuals suffer from these gastric diseases and rest of the infected individuals remain asymptomatic. The genotypes of H. pylori, host genetic background, lifestyle including smoking and diet may determine clinical outcomes. People from different geographical regions have different food habits, which also include several unique fermented products of plant and animal origins. When consumed raw, the fermented foods bring in fresh inocula of microbes to gastrointestinal tract and several strains of these microbes, like Lactobacillus and Saccharomyces are known probiotics. In vitro and in vivo experiments as well as clinical trials suggest that several probiotics have anti-H. pylori effects. Here we discuss the possibility of using natural probiotics present in traditional fermented food and beverages to obtain protection against H. pylori induced gastric diseases.
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Affiliation(s)
| | | | | | - Santanu Chattopadhyay
- Microbiome Research Facility, Microbiome Biology, Rajiv Gandhi Centre for BiotechnologyTrivandrum, India
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39
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Ricci V. Relationship between VacA Toxin and Host Cell Autophagy in Helicobacter pylori Infection of the Human Stomach: A Few Answers, Many Questions. Toxins (Basel) 2016; 8:toxins8070203. [PMID: 27376331 PMCID: PMC4963836 DOI: 10.3390/toxins8070203] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2016] [Revised: 06/14/2016] [Accepted: 06/17/2016] [Indexed: 02/06/2023] Open
Abstract
Helicobacter pylori is a Gram-negative bacterium that colonizes the stomach of about half the global population and represents the greatest risk factor for gastric malignancy. The relevance of H. pylori for gastric cancer development is equivalent to that of tobacco smoking for lung cancer. VacA toxin seems to play a pivotal role in the overall strategy of H. pylori towards achieving persistent gastric colonization. This strategy appears to involve the modulation of host cell autophagy. After an overview of autophagy and its role in infection and carcinogenesis, I critically review current knowledge about the action of VacA on host cell autophagy during H. pylori infection of the human stomach. Although VacA is a key player in modulation of H. pylori-induced autophagy, a few discrepancies in the data are also evident and many questions remain to be answered. We are thus still far from a definitive understanding of the molecular mechanisms through which VacA affects autophagy and the consequences of this toxin action on the overall pathogenic activity of H. pylori.
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Affiliation(s)
- Vittorio Ricci
- Department of Molecular Medicine, Human Physiology Unit, University of Pavia Medical School, Via Forlanini 6, 27100 Pavia, Italy.
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40
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Utsch C, Haas R. VacA's Induction of VacA-Containing Vacuoles (VCVs) and Their Immunomodulatory Activities on Human T Cells. Toxins (Basel) 2016; 8:toxins8060190. [PMID: 27322323 PMCID: PMC4926156 DOI: 10.3390/toxins8060190] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2016] [Revised: 06/11/2016] [Accepted: 06/15/2016] [Indexed: 12/11/2022] Open
Abstract
Vacuolating cytotoxin A (VacA) is a secreted pore-forming toxin and one of the major virulence factors of Helicobacter pylori (H. pylori), which actively supports the persistence and survival of the bacteria in the special ecological niche of the human stomach. H. pylori genomes harbor different allelic forms of the vacA gene, which translate into functionally distinct VacA toxin types. VacA internalizes into various cell types via membrane or specific receptor interactions finally forming acidic endocytic VacA-containing vacuoles (VCVs). In this review, we focus on different characteristics of VacA, its interaction with host cells, the formation and protein content of VCVs and their intracellular transport into human T cells, which finally leads to the immunosuppressive phenotype of VacA. Immunomodulatory activities of VacA on human T cells are discussed with a focus on T-cell proliferation and calcium signaling.
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Affiliation(s)
- Ciara Utsch
- Max von Pettenkofer-Institut für Hygiene und Medizinische Mikrobiologie, Ludwig-Maximilians-Universität, Pettenkoferstraße 9a, München D-80336, Germany
| | - Rainer Haas
- Max von Pettenkofer-Institut für Hygiene und Medizinische Mikrobiologie, Ludwig-Maximilians-Universität, Pettenkoferstraße 9a, München D-80336, Germany.
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Foegeding NJ, Caston RR, McClain MS, Ohi MD, Cover TL. An Overview of Helicobacter pylori VacA Toxin Biology. Toxins (Basel) 2016; 8:toxins8060173. [PMID: 27271669 PMCID: PMC4926140 DOI: 10.3390/toxins8060173] [Citation(s) in RCA: 129] [Impact Index Per Article: 16.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2016] [Revised: 05/18/2016] [Accepted: 05/27/2016] [Indexed: 12/11/2022] Open
Abstract
The VacA toxin secreted by Helicobacter pylori enhances the ability of the bacteria to colonize the stomach and contributes to the pathogenesis of gastric adenocarcinoma and peptic ulcer disease. The amino acid sequence and structure of VacA are unrelated to corresponding features of other known bacterial toxins. VacA is classified as a pore-forming toxin, and many of its effects on host cells are attributed to formation of channels in intracellular sites. The most extensively studied VacA activity is its capacity to stimulate vacuole formation, but the toxin has many additional effects on host cells. Multiple cell types are susceptible to VacA, including gastric epithelial cells, parietal cells, T cells, and other types of immune cells. This review focuses on the wide range of VacA actions that are detectable in vitro, as well as actions of VacA in vivo that are relevant for H. pylori colonization of the stomach and development of gastric disease.
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Affiliation(s)
- Nora J Foegeding
- Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA.
| | - Rhonda R Caston
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA.
| | - Mark S McClain
- Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN 37232, USA.
| | - Melanie D Ohi
- Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA.
- Center for Structural Biology, Vanderbilt University, Nashville, TN 37232, USA.
| | - Timothy L Cover
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA.
- Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN 37232, USA.
- Veterans Affairs Tennessee Valley Healthcare System, Nashville, TN 37212, USA.
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Yahiro K, Hirayama T, Moss J, Noda M. New Insights into VacA Intoxication Mediated through Its Cell Surface Receptors. Toxins (Basel) 2016; 8:toxins8050152. [PMID: 27187473 PMCID: PMC4885067 DOI: 10.3390/toxins8050152] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2016] [Revised: 05/05/2016] [Accepted: 05/06/2016] [Indexed: 12/17/2022] Open
Abstract
Helicobacter pylori (H. pylori), a major cause of gastroduodenal diseases, produces VacA, a vacuolating cytotoxin associated with gastric inflammation and ulceration. The C-terminal domain of VacA plays a crucial role in receptor recognition on target cells. We have previously identified three proteins (i.e., RPTPα, RPTPβ, and LRP1) that serve as VacA receptors. These receptors contribute to the internalization of VacA into epithelial cells, activate signal transduction pathways, and contribute to cell death and gastric ulceration. In addition, other factors (e.g., CD18, sphingomyelin) have also been identified as cell-surface, VacA-binding proteins. Since we believe that, following interactions with its host cell receptors, VacA participates in events leading to disease, a better understanding of the cellular function of VacA receptors may provide valuable information regarding the mechanisms underlying the pleiotropic actions of VacA and the pathogenesis of H. pylori-mediated disease. In this review, we focus on VacA receptors and their role in events leading to cell damage.
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Affiliation(s)
- Kinnosuke Yahiro
- Department of Molecular Infectiology, Graduate School of Medicine, Chiba University, 1-8-1, Inohana, Chuo-ku, Chiba 260-8670, Japan.
| | - Toshiya Hirayama
- Department of Bacteriology, Institute of Tropical Medicine, Nagasaki University, 1-12-4, Sakamoto, Nagasaki 852-8523, Japan.
| | - Joel Moss
- Cardiovascular and Pulmonary Branch, NHLBI, NIH, Building 10, Room 6D03, MSC 1590, Bethesda, MD 20892-1590, USA.
| | - Masatoshi Noda
- Department of Molecular Infectiology, Graduate School of Medicine, Chiba University, 1-8-1, Inohana, Chuo-ku, Chiba 260-8670, Japan.
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43
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Kwon YC, Kim S, Lee YS, Lee JC, Cho MJ, Lee WK, Kang HL, Song JY, Baik SC, Ro HS. Novel nuclear targeting coiled-coil protein of Helicobacter pylori showing Ca2+-independent, Mg2+-dependent DNase I activity. J Microbiol 2016; 54:387-95. [DOI: 10.1007/s12275-016-5631-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Revised: 03/30/2016] [Accepted: 03/30/2016] [Indexed: 01/02/2023]
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Khalilpour A, Kazemzadeh-Narbat M, Tamayol A, Oklu R, Khademhosseini A. Biomarkers and diagnostic tools for detection of Helicobacter pylori. Appl Microbiol Biotechnol 2016; 100:4723-34. [DOI: 10.1007/s00253-016-7495-7] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2016] [Revised: 03/21/2016] [Accepted: 03/22/2016] [Indexed: 12/13/2022]
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45
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Al-Ezzy AIA. Immunomodulatory Effect of H. Pylori CagA Genotype and Gastric Hormones On Gastric Versus Inflammatory Cells Fas Gene Expression in Iraqi Patients with Gastroduodenal Disorders. Open Access Maced J Med Sci 2016; 4:364-373. [PMID: 27703557 PMCID: PMC5042617 DOI: 10.3889/oamjms.2016.032] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2016] [Revised: 02/19/2016] [Accepted: 02/20/2016] [Indexed: 02/06/2023] Open
Abstract
AIM: To evaluate the Immunomodulatory effects of CagA expression; pepsinogen I, II & gastrin-17 on PMNs and lymphocytes Fas expression in inflammatory and gastric cells; demographic distribution of Fas molecule in gastric tissue and inflammatory cells. METHODS: Gastroduodenal biopsies were taken from 80 patients for histopathology and H. pylori diagnosis. Serum samples were used for evaluation of pepsinogen I (PGI); (PGII); gastrin-17 (G-17). RESULTS: Significant difference (p < 0.001) in lymphocytes & PMNs Fas expression; epithelial & lamina propria Fas localization among H. pylori associated gastric disorders. No correlation between grade of lymphocytes & PMNs Fas expression in gastric epithelia; lamina propria and types of gastric disorder. Significant difference (p < 0.001) in total gastric Fas expression, epithelial Fas; lamina propria and gastric gland Fas expression according to CagA, PGI; PGII; PGI/PGII; Gastrin-17. Total gastric Fas expression has significant correlation with CagA, PGII levels. Gastric epithelial and gastric lamina propria Fas expression have significant correlation with CagA, PGI; PGII levels. Significant difference (p < 0.001) was found in lymphocytes & PMNs Fas expression; epithelial & lamina propria localization of lymphocytes & PMNs Fas expression according to CagA, PGI; PGII; PGI/PGII; Gastrin-17. Lymphocytes Fas expression have correlation with PGI, PGII, PGI/PGII. PMNs Fas expression have correlation with PGI, PGII. CONCLUSION: Fas gene expression and localization on gastric and inflammatory cells affected directly by H. pylori CagA and indirectly by gastric hormones. This contributes to progression of various gastric disorders according to severity of CagA induced gastric pathology and gastric hormones disturbance throughout the course of infection and disease.
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Affiliation(s)
- Ali Ibrahim Ali Al-Ezzy
- Department of Pathology, College of Veterinary Medicine, Diyala University, Baquba, Diyala Province, Iraq
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Valenzuela MA, Canales J, Corvalán AH, Quest AFG. Helicobacter pylori-induced inflammation and epigenetic changes during gastric carcinogenesis. World J Gastroenterol 2015; 21:12742-12756. [PMID: 26668499 PMCID: PMC4671030 DOI: 10.3748/wjg.v21.i45.12742] [Citation(s) in RCA: 79] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/27/2015] [Revised: 08/08/2015] [Accepted: 10/13/2015] [Indexed: 02/06/2023] Open
Abstract
The sequence of events associated with the development of gastric cancer has been described as “the gastric precancerous cascade”. This cascade is a dynamic process that includes lesions, such as atrophic gastritis, intestinal metaplasia and dysplasia. According to this model, Helicobacter pylori (H. pylori) infection targets the normal gastric mucosa causing non-atrophic gastritis, an initiating lesion that can be cured by clearing H. pylori with antibiotics or that may then linger in the case of chronic infection and progress to atrophic gastritis. The presence of virulence factors in the infecting H. pylori drives the carcinogenesis process. Independent epidemiological and animal studies have confirmed the sequential progression of these precancerous lesions. Particularly long-term follow-up studies estimated a risk of 0.1% for atrophic gastritis/intestinal metaplasia and 6% in case of dysplasia for the long-term development of gastric cancer. With this in mind, a better understanding of the genetic and epigenetic changes associated with progression of the cascade is critical in determining the risk of gastric cancer associated with H. pylori infection. In this review, we will summarize some of the most relevant mechanisms and focus predominantly but not exclusively on the discussion of gene promoter methylation and miRNAs in this context.
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IL-4 Protects the Mitochondria Against TNFα and IFNγ Induced Insult During Clearance of Infection with Citrobacter rodentium and Escherichia coli. Sci Rep 2015; 5:15434. [PMID: 26481427 PMCID: PMC4613366 DOI: 10.1038/srep15434] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2015] [Accepted: 09/24/2015] [Indexed: 11/08/2022] Open
Abstract
Citrobacter rodentium is a murine pathogen that serves as a model for enteropathogenic Escherichia coli. C. rodentium infection reduced the quantity and activity of mitochondrial respiratory complexes I and IV, as well as phosphorylation capacity, mitochondrial transmembrane potential and ATP generation at day 10, 14 and 19 post infection. Cytokine mRNA quantification showed increased levels of IFNγ, TNFα, IL-4, IL-6, and IL-12 during infection. The effects of adding these cytokines, C. rodentium and E. coli were hence elucidated using an in vitro colonic mucosa. Both infection and TNFα, individually and combined with IFNγ, decreased complex I and IV enzyme levels and mitochondrial function. However, IL-4 reversed these effects, and IL-6 protected against loss of complex IV. Both in vivo and in vitro, the dysfunction appeared caused by nitric oxide-generation, and was alleviated by an antioxidant targeting mitochondria. IFNγ −/− mice, containing a similar pathogen burden but higher IL-4 and IL-6, displayed no loss of any of the four complexes. Thus, the cytokine environment appears to be a more important determinant of mitochondrial function than direct actions of the pathogen. As IFNγ and TNFα levels increase during clearance of infection, the concomitant increase in IL-4 and IL-6 protects mitochondrial function.
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48
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Helicobacter pylori CagA Suppresses Apoptosis through Activation of AKT in a Nontransformed Epithelial Cell Model of Glandular Acini Formation. BIOMED RESEARCH INTERNATIONAL 2015; 2015:761501. [PMID: 26557697 PMCID: PMC4628739 DOI: 10.1155/2015/761501] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/04/2015] [Revised: 04/16/2015] [Accepted: 04/20/2015] [Indexed: 02/07/2023]
Abstract
H. pylori infection is the most important environmental risk to develop gastric cancer, mainly through its virulence factor CagA. In vitro models of CagA function have demonstrated a phosphoprotein activity targeting multiple cellular signaling pathways, while cagA transgenic mice develop carcinomas of the gastrointestinal tract, supporting oncogenic functions. However, it is still not completely clear how CagA alters cellular processes associated with carcinogenic events. In this study, we evaluated the capacity of H. pylori CagA positive and negative strains to alter nontransformed MCF-10A glandular acini formation. We found that CagA positive strains inhibited lumen formation arguing for an evasion of apoptosis activity of central acini cells. In agreement, CagA positive strains induced a cell survival activity that correlated with phosphorylation of AKT and of proapoptotic proteins BIM and BAD. Anoikis is a specific type of apoptosis characterized by AKT and BIM activation and it is the mechanism responsible for lumen formation of MCF-10A acini in vitro and mammary glands in vivo. Anoikis resistance is also a common mechanism of invading tumor cells. Our data support that CagA positive strains signaling function targets the AKT and BIM signaling pathway and this could contribute to its oncogenic activity through anoikis evasion.
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49
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Lekakarn H, Promdonkoy B, Boonserm P. Interaction of Lysinibacillus sphaericus binary toxin with mosquito larval gut cells: Binding and internalization. J Invertebr Pathol 2015; 132:125-131. [PMID: 26408968 DOI: 10.1016/j.jip.2015.09.010] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2015] [Revised: 07/29/2015] [Accepted: 09/23/2015] [Indexed: 01/02/2023]
Abstract
The binary toxin produced by Lysinibacillus sphaericus is composed of BinA and BinB subunits. Together, but not separately, the two subunits are highly toxic to Culex quinquefasciatus larvae, but show no toxicity to Aedes aegypti. The molecular mechanism underlying intoxication has not been clearly elucidated. The present study compares the binding and the internalization of binary toxin into the midgut epithelial cells of susceptible C. quinquefasciatus mosquito larvae with those of Bin-refractory A. aegypti. The guts from larvae fed with fluorescently labeled toxin were dissected and analyzed using a confocal laser scanning microscope. When fed with a mixture of both components, co-localization of BinA and BinB was detected both on the cell surface and in the cytoplasm of Culex larval gut cells. However, administration of BinA alone resulted in localization only on the cell membrane, whereas BinB alone was detected both on the cell membrane and inside the cytoplasm. In contrast, when a mixture of both components, or each individual component, was fed to Aedes larvae, BinA and BinB were unable to reach the cytoplasm and were localized only on the cell membrane. These results are consistent with the suggestion that the internalization of BinA is essential for toxicity, and that BinB is required for this internalization into susceptible larval gut cells.
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Affiliation(s)
- Hataikarn Lekakarn
- Institute of Molecular Biosciences, Mahidol University, Salaya, Phuttamonthon, Nakhon Pathom 73170, Thailand
| | - Boonhiang Promdonkoy
- National Center for Genetic Engineering and Biotechnology, National Science and Technology Development Agency, 113 Pahonyothin Road, Khlong Luang, Pathumthani 12120, Thailand
| | - Panadda Boonserm
- Institute of Molecular Biosciences, Mahidol University, Salaya, Phuttamonthon, Nakhon Pathom 73170, Thailand.
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50
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Amilon KR, Letley DP, Winter JA, Robinson K, Atherton JC. Expression of the Helicobacter pylori virulence factor vacuolating cytotoxin A (vacA) is influenced by a potential stem-loop structure in the 5' untranslated region of the transcript. Mol Microbiol 2015; 98:831-46. [PMID: 26259667 PMCID: PMC4843948 DOI: 10.1111/mmi.13160] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/08/2015] [Indexed: 01/03/2023]
Abstract
The vacuolating cytotoxin, VacA, is an important virulence factor secreted by the gastric pathogen Helicobacter pylori. Certain vacA genotypes are strongly associated with disease risk, but the association is not absolute. The factors determining vacA gene expression are not fully understood, and the mechanisms of its regulation are elusive. We have identified a potential mRNA stem‐loop forming structure in the 5′ untranslated region (UTR) of the vacA transcript. Using site‐directed mutagenesis, we found that disruption of the stem‐loop structure reduced steady‐state mRNA levels between two‐ and sixfold (P = 0.0005) and decreased mRNA half‐life compared with wild type (P = 0.03). This led to a marked reduction in VacA protein levels and overall toxin activity. Additionally, during stressful environmental conditions of acid pH or high environmental salt concentrations, when general transcription of vacA was decreased or increased respectively, the stabilising effects of the stem‐loop were even more pronounced. Our results suggest that the stem‐loop structure in the vacA 5′ UTR is an important determinant of vacA expression through stabilisation of the vacA mRNA transcript and that the stabilising effect is of particular importance during conditions of environmental stress.
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Affiliation(s)
- Karin R Amilon
- Nottingham Digestive Diseases Biomedical Research Unit, School of Medicine, University of Nottingham, Nottingham, UK
| | - Darren P Letley
- Nottingham Digestive Diseases Biomedical Research Unit, School of Medicine, University of Nottingham, Nottingham, UK
| | - Jody A Winter
- Nottingham Digestive Diseases Biomedical Research Unit, School of Medicine, University of Nottingham, Nottingham, UK
| | - Karen Robinson
- Nottingham Digestive Diseases Biomedical Research Unit, School of Medicine, University of Nottingham, Nottingham, UK
| | - John C Atherton
- Nottingham Digestive Diseases Biomedical Research Unit, School of Medicine, University of Nottingham, Nottingham, UK
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