scholarly journals Natural History of Gastric Mucosal Cytokine Expression in Helicobacter pylori Gastritis in Mongolian Gerbils

2005 ◽  
Vol 73 (4) ◽  
pp. 2205-2212 ◽  
Author(s):  
Yoshio Yamaoka ◽  
Kazuyoshi Yamauchi ◽  
Hiroyoshi Ota ◽  
Atsushi Sugiyama ◽  
Satoshi Ishizone ◽  
...  
Keyword(s):  
Helicobacter Pylori ◽  
Gastric Ulcers ◽  
Mongolian Gerbils ◽  
Mrna Levels ◽  
Hyperplastic Polyps ◽  
Fundic Mucosa ◽  
Reverse Transcription Pcr ◽  
Pyloric Mucosa ◽  
Ifn Γ ◽  
H Pylori

ABSTRACT Data regarding the chronological changes in gastric mucosal cytokines in the different phases of Helicobacter pylori infection are unavailable. We examined Mongolian gerbils for up to 52 weeks after H. pylori (ATCC 43504) inoculation. Levels of mRNAs of mucosal cytokines (interleukin-1β [IL-1β], gamma interferon [IFN-γ], IL-4, IL-6, and IL-10) were assessed using real-time reverse transcription-PCR. Starting 26 weeks after H. pylori inoculation, two clinicohistologic patterns appeared: gastric ulcers in 32% and hyperplastic polyps in 68% of gerbils. High levels of mucosal IL-1β mRNA were observed early in the infection, reaching maximum at 4 weeks and then rapidly declining. Mucosal IFN-γ mRNA also reached maximal levels at 4 weeks but remained high thereafter. Both IL-1β and IFN-γ mRNA levels were consistently higher in the pyloric mucosa than in the fundic mucosa. In contrast, IL-4, IL-6, and IL-10 mRNA levels peaked at 8 to 26 weeks and levels were similar in the pyloric mucosa and the fundic mucosa. IFN-γ mRNA levels were significantly higher in gerbils with ulcers than in those with hyperplastic polyps (median IFN-γ/glyceraldehyde-3-phosphate dehydrogenase ratio × 100,000 = 650 versus 338, respectively [antrum], and 172 versus 40, respectively [corpus]) (P < 0.05). We propose that the different outcomes (e.g., ulcers or hyperplastic polyps) might relate to imbalances among cytokines.

scholarly journals Coinfection with Enterohepatic Helicobacter Species Can Ameliorate or Promote Helicobacter pylori-Induced Gastric Pathology in C57BL/6 Mice

2011 ◽  
Vol 79 (10) ◽  
pp. 3861-3871 ◽  
Author(s):  
Zhongming Ge ◽  
Yan Feng ◽  
Sureshkumar Muthupalani ◽  
Laura Lemke Eurell ◽  
Nancy S. Taylor ◽  
...  
Keyword(s):  
Helicobacter Pylori ◽  
Interleukin 17 ◽  
Mrna Levels ◽  
Cytokine Mrna ◽  
Content Type ◽  
Time Points ◽  
Gastric Pathology ◽  
Tnf Α ◽  
Ifn Γ ◽  
H Pylori

ABSTRACTTo investigate how different enterohepaticHelicobacterspecies (EHS) influenceHelicobacter pylorigastric pathology, C57BL/6 mice were infected withHelicobacter hepaticusorHelicobacter muridarum, followed byH. pyloriinfection 2 weeks later. Compared toH. pylori-infected mice, mice infected withH. muridarumandH. pylori(HmHp mice) developed significantly lower histopathologic activity index (HAI) scores (P< 0.0001) at 6 and 11 months postinoculation (MPI). However, mice infected withH. hepaticusandH. pylori(HhHp mice) developed more severe gastric pathology at 6 MPI (P= 0.01), with a HAI at 11 MPI (P= 0.8) similar to that ofH. pylori-infected mice.H. muridarum-mediated attenuation of gastritis in coinfected mice was associated with significant downregulation of proinflammatory Th1 (interlukin-1beta [Il-1β], gamma interferon [Ifn-γ], and tumor necrosis factor-alpha [Tnf-α]) cytokines at both time points and Th17 (Il-17A) cytokine mRNA levels at 6 MPI in murine stomachs compared to those ofH. pylori-infected mice (P< 0.01). Coinfection withH. hepaticusalso suppressedH. pylori-induced elevation of gastric Th1 cytokinesIfn-γandTnf-α(P< 0.0001) but increased Th17 cytokine mRNA levels (P= 0.028) at 6 MPI. Furthermore, mRNA levels ofIl-17Awere positively correlated with the severity of helicobacter-induced gastric pathology (HhHp>H. pylori>HmHp) (at 6 MPI,r2= 0.92,P< 0.0001; at 11 MPI,r2= 0.82,P< 0.002). Despite disparate effects on gastritis, colonization levels of gastricH. pyloriwere increased in HhHp mice (at 6 MPI) and HmHp mice (at both time points) compared to those in mono-H. pylori-infected mice. These data suggest that despite consistent downregulation of Th1 responses, EHS coinfection either attenuated or promoted the severity ofH. pylori-induced gastric pathology in C57BL/6 mice. This modulation was related to the variable effects of EHS on gastric interleukin 17 (IL-17) responses toH. pyloriinfection.

Perfil Epidemiológico de Pacientes Submetidos à Biópsia Gástrica em um Hospital Escola do Sul de Minas Gerais/ Epidemiological Profile of Patients Undergo Gastric Biopsy in a School Hospital of Minas Gerais

1970 ◽  
Vol 4 (3) ◽  
pp. 48-57
Author(s):  
Isabela Maria A. Ribeiro Simões ◽  
Ana Carolina Mauad Coli ◽  
Roseane de Souza Candido Irulegui
Keyword(s):  
Helicobacter Pylori ◽  
Age Groups ◽  
Epidemiological Data ◽  
Minas Gerais ◽  
Gastric Biopsy ◽  
Gastric Ulcers ◽  
Histopathological Diagnosis ◽  
Gastric Diseases ◽  
H Pylori ◽  
Epidemiological Profile

Objetivo: Determinar a prevalência de lesões benignas e neoplasia gástrica através do estudo de biópsias realizadas em um Hospital Escola do Sul de Minas Gerais, no período entre 2007 e 2011. Materiais e Métodos: A pesquisa documental foi quantitativa e retrospectiva, baseada na análise dos registros de biópsias e prontuários. Realizou-se o levantamento de dados referentes à idade, gênero, cor, profissão, diagnóstico histopatológico e presença de Helicobacter pylori nas amostras. Resultados: O número total de biópsias gástricas analisadas foi de 1225, cujo perfil populacional encontrado foi: idade média de 56,75 anos, sexo masculino (52%), cor branca (81,9 %), aposentado (30%). Os diagnósticos mais frequentes foram: gastrites (71,9%), pólipos (14,2%), adenocarcinomas (5,9%), úlceras gástricas (6%), linfomas (0,4%), sem alterações (0,4%) e outros (1,2%). Em outros, encontram-se achados de malignidade, metaplasia e xantelasma gástrico. Em relação à presença de Helicobacter pylori nas amostras, o resultado encontrado foi de24% positivas, 46% negativas e 30% não pesquisadas. Conclusão: Os resultados confirmam a alta frequência das doenças gástricas e sua incidência nas diversas faixas etárias, além do envolvimento do H. pylori em tais afecções. É de grande importância a caracterização dos dados epidemiológicos, o que permite prováveis direcionamentos para programas de prevenção e informação para a população. Palavras-chave: biópsia gástrica, gastropatia, perfil epidemiológico.  ABSTRACTObjective: To determine the prevalence of benign lesions and gastric cancer through study of biopsies performed at a school hospital in southern Minas Gerais, in the period between 2007 and 2011.Materials and Methods: The research was quantitative and retrospective, based on analysis of biopsies records and medical records. We conducted the survey data regarding age, sex, color, profession, histopathological diagnosis and the presence of Helicobacter pylori in the samples. Results: The total number of gastric biopsies analyzed was 1225. Population listing was found: mean age of 56.75 years, male (52%), white (81.9%), retired (30%). The most frequent diagnoses were gastritis (71.9%), polyps (14.2%), adenocarcinomas (5.9%), gastric ulcers (6%), lymphoma (0.4%), unchanged (0, 4%) and others (1.2%). In others, there are: findings of malignancy, metaplasia, gastric xanthelasma. Regarding the presence of Helicobacter pylori in the sample, the result was: 24% positive, 46% negative, 30% non searched. Conclusion: The results confirm the high frequency of gastric diseases and their incidence in the various age groups additionally to the involvement of H. pylori in such conditions. It is of great importance to characterize the epidemiological data, allowing probable directions for prevention and information programs for population. Keywords: gastric biopsy, gastropathy, epidemiological profile

scholarly journals Selective killing of Helicobacter pylori with pH-responsive helix–coil conformation transitionable antimicrobial polypeptides

2017 ◽  
Vol 114 (48) ◽  
pp. 12675-12680 ◽  
Author(s):  
Menghua Xiong ◽  
Yan Bao ◽  
Xin Xu ◽  
Hua Wang ◽  
Zhiyuan Han ◽  
...  
Keyword(s):  
Helicobacter Pylori ◽  
Triple Therapy ◽  
Helical Structure ◽  
Commensal Bacteria ◽  
Gastric Ulcers ◽  
Normal Tissues ◽  
Minimal Toxicity ◽  
Antimicrobial Polypeptides ◽  
H Pylori ◽  
Drug Resistant Strains

Current clinical treatment of Helicobacter pylori infection, the main etiological factor in the development of gastritis, gastric ulcers, and gastric carcinoma, requires a combination of at least two antibiotics and one proton pump inhibitor. However, such triple therapy suffers from progressively decreased therapeutic efficacy due to the drug resistance and undesired killing of the commensal bacteria due to poor selectivity. Here, we report the development of antimicrobial polypeptide-based monotherapy, which can specifically kill H. pylori under acidic pH in the stomach while inducing minimal toxicity to commensal bacteria under physiological pH. Specifically, we designed a class of pH-sensitive, helix–coil conformation transitionable antimicrobial polypeptides (HCT-AMPs) (PGA)m-r-(PHLG-MHH)n, bearing randomly distributed negatively charged glutamic acid and positively charged poly(γ-6-N-(methyldihexylammonium)hexyl-l-glutamate) (PHLG-MHH) residues. The HCT-AMPs showed unappreciable toxicity at physiological pH when they adopted random coiled conformation. Under acidic condition in the stomach, they transformed to the helical structure and exhibited potent antibacterial activity against H. pylori, including clinically isolated drug-resistant strains. After oral gavage, the HCT-AMPs afforded comparable H. pylori killing efficacy to the triple-therapy approach while inducing minimal toxicity against normal tissues and commensal bacteria, in comparison with the remarkable killing of commensal bacteria by 65% and 86% in the ileal contents and feces, respectively, following triple therapy. This strategy renders an effective approach to specifically target and kill H. pylori in the stomach while not harming the commensal bacteria/normal tissues.

scholarly journals TIFA Signaling in Gastric Epithelial Cells Initiates the cag Type 4 Secretion System-Dependent Innate Immune Response to Helicobacter pylori Infection

mBio ◽  
2017 ◽  
Vol 8 (4) ◽  
Author(s):  
Alevtina Gall ◽  
Ryan G. Gaudet ◽  
Scott D. Gray-Owen ◽  
Nina R. Salama
Keyword(s):  
Immune Response ◽  
Helicobacter Pylori ◽  
Epithelial Cells ◽  
Inflammatory Response ◽  
Secretion System ◽  
Innate Immune ◽  
Gastric Ulcers ◽  
Bacterial Clearance ◽  
Gastric Epithelial Cells ◽  
H Pylori

ABSTRACT Helicobacter pylori is a bacterial pathogen that colonizes the human stomach, causing inflammation which, in some cases, leads to gastric ulcers and cancer. The clinical outcome of infection depends on a complex interplay of bacterial, host genetic, and environmental factors. Although H. pylori is recognized by both the innate and adaptive immune systems, this rarely results in bacterial clearance. Gastric epithelial cells are the first line of defense against H. pylori and alert the immune system to bacterial presence. Cytosolic delivery of proinflammatory bacterial factors through the cag type 4 secretion system ( cag -T4SS) has long been appreciated as the major mechanism by which gastric epithelial cells detect H. pylori . Classically attributed to the peptidoglycan sensor NOD1, recent work has highlighted the role of NOD1-independent pathways in detecting H. pylori ; however, the bacterial and host factors involved have remained unknown. Here, we show that bacterially derived heptose-1,7-bisphosphate (HBP), a metabolic precursor in lipopolysaccharide (LPS) biosynthesis, is delivered to the host cytosol through the cag -T4SS, where it activates the host tumor necrosis factor receptor-associated factor (TRAF)-interacting protein with forkhead-associated domain (TIFA)-dependent cytosolic surveillance pathway. This response, which is independent of NOD1, drives robust NF-κB-dependent inflammation within hours of infection and precedes NOD1 activation. We also found that the CagA toxin contributes to the NF-κB-driven response subsequent to TIFA and NOD1 activation. Taken together, our results indicate that the sequential activation of TIFA, NOD1, and CagA delivery drives the initial inflammatory response in gastric epithelial cells, orchestrating the subsequent recruitment of immune cells and leading to chronic gastritis. IMPORTANCE H. pylori is a globally prevalent cause of gastric and duodenal ulcers and cancer. H. pylori antibiotic resistance is rapidly increasing, and a vaccine remains elusive. The earliest immune response to H. pylori is initiated by gastric epithelial cells and sets the stage for the subsequent immunopathogenesis. This study revealed that host TIFA and H. pylori -derived HBP are critical effectors of innate immune signaling that account for much of the inflammatory response to H. pylori in gastric epithelial cells. HBP is delivered to the host cell via the cag -T4SS at a time point that precedes activation of the previously described NOD1 and CagA inflammatory pathways. Manipulation of the TIFA-driven immune response in the host and/or targeting of ADP-heptose biosynthesis enzymes in H. pylori may therefore provide novel strategies that may be therapeutically harnessed to achieve bacterial clearance.

scholarly journals Helicobacter Pylori Targets the EPHA2 Receptor Tyrosine Kinase in Gastric Cells Modulating Key Cellular Functions

Cells ◽  
2020 ◽  
Vol 9 (2) ◽  
pp. 513 ◽  
Author(s):  
Marina Leite ◽  
Miguel S. Marques ◽  
Joana Melo ◽  
Marta T. Pinto ◽  
Bruno Cavadas ◽  
...  
Keyword(s):  
Helicobacter Pylori ◽  
Tyrosine Kinase ◽  
Signaling Pathways ◽  
Receptor Tyrosine Kinase ◽  
Tyrosine Kinases ◽  
Receptor Tyrosine Kinases ◽  
Receptor Activation ◽  
Degradation Pathway ◽  
Mrna Levels ◽  
H Pylori

Helicobacter pylori, a stomach-colonizing Gram-negative bacterium, is the main etiological factor of various gastroduodenal diseases, including gastric adenocarcinoma. By establishing a life-long infection of the gastric mucosa, H. pylori continuously activates host-signaling pathways, in particular those associated with receptor tyrosine kinases. Using two different gastric epithelial cell lines, we show that H. pylori targets the receptor tyrosine kinase EPHA2. For long periods of time post-infection, H. pylori induces EPHA2 protein downregulation without affecting its mRNA levels, an effect preceded by receptor activation via phosphorylation. EPHA2 receptor downregulation occurs via the lysosomal degradation pathway and is independent of the H. pylori virulence factors CagA, VacA, and T4SS. Using small interfering RNA, we show that EPHA2 knockdown affects cell–cell and cell–matrix adhesion, invasion, and angiogenesis, which are critical cellular processes in early gastric lesions and carcinogenesis mediated by the bacteria. This work contributes to the unraveling of the underlying mechanisms of H. pylori–host interactions and associated diseases. Additionally, it raises awareness for potential interference between H. pylori infection and the efficacy of gastric cancer therapies targeting receptors tyrosine kinases, given that infection affects the steady-state levels and dynamics of some receptor tyrosine kinases (RTKs) and their signaling pathways.

scholarly journals Molecular Characterization of a Flagellar Export Locus of Helicobacter pylori

1999 ◽  
Vol 67 (5) ◽  
pp. 2060-2070 ◽  
Author(s):  
Steffen Porwollik ◽  
Brian Noonan ◽  
Paul W. O’Toole
Keyword(s):  
Helicobacter Pylori ◽  
Virulence Factor ◽  
Housekeeping Genes ◽  
Reading Frame ◽  
Reverse Transcription Pcr ◽  
Mutant Strains ◽  
H Pylori ◽  
Export Protein ◽  
Successful Colonization

ABSTRACT Motility of Helicobacter species has been shown to be essential for successful colonization of the host. We have investigated the organization of a flagellar export locus in Helicobacter pylori. A 7-kb fragment of the H. pylori CCUG 17874 genome was cloned and sequenced, revealing an operon comprising an open reading frame of unknown function (ORF03), essential housekeeping genes (ileS and murB), flagellar export genes (fliI and fliQ), and a homolog to a gene implicated in virulence factor transport in other pathogens (virB11). A promoter for this operon, showing similarity to the Escherichia coli ς70 consensus, was identified by primer extension. Cotranscription of the genes in the operon was demonstrated by reverse transcription-PCR, and transcription of virB11, fliI, fliQ, andmurB was detected in human or mouse biopsies obtained from infected hosts. The genetic organization of this locus was conserved in a panel of H. pylori clinical isolates. EngineeredfliI and fliQ mutant strains were completely aflagellate and nonmotile, whereas a virB11 mutant still produced flagella. The fliI and fliQ mutant strains produced reduced levels of flagellin and the hook protein FlgE. Production of OMP4, a member of the outer membrane protein family identified in H. pylori 26695, was reduced in both thevirB11 mutant and the fliI mutant, suggesting related functions of the virulence factor export protein (VirB11) and the flagellar export component (FliI).

scholarly journals Prevalence of Helicobacter pylori infection among patients undergoing upper gastrointestinal endoscopy

2015 ◽  
Vol 3 (1) ◽  
Author(s):  
Vudumula Vijaya Lakshmi
Keyword(s):  
Duodenal Ulcer ◽  
Helicobacter Pylori ◽  
Normal Population ◽  
Gastric Ulcers ◽  
Upper Gastrointestinal Endoscopy ◽  
Contributing Factors ◽  
Duodenal Ulcers ◽  
Female Ratio ◽  
Ulcer Disease ◽  
H Pylori

Helicobacter pylori (H. pylori) has a role in the multifactorial etiology of peptic ulcer disease. A link between H. pylori infection and duodenal ulcer disease is now established. Other contributing factors and their interaction with the organism may initiate the ulcerative process. The fact that eradication of H. pylori infection leads to a long-term cure in the majority of duodenal ulcer patients and the fact that the prevalence of infection is higher in ulcer patients than in the normal population are cogent arguments in favor of it being the primary cause of the ulceration. This study was under taken at the Department of surgery, Narayana medical college, Nellore from January 2007 to July 2008. A total of 150 patients with duodenal ulcers, gastric ulcers, antral gastritis, gastric carcinoma and dyspepsia of any kind were studied. Maximum number of cases were in the age group of 31 years to 50 years among both sexes and number of cases gradually decreased after 50 years of age in males and females. Males were more in number and male to female ratio is (2.75:1) approximately 3:1.

scholarly journals Expressions of MMPs and TIMP-1 in Gastric Ulcers May DifferentiateH. pylori-Infected from NSAID-Related Ulcers

2012 ◽  
Vol 2012 ◽  
pp. 1-9 ◽  
Author(s):  
Hsiu-Chi Cheng ◽  
Hsiao-Bai Yang ◽  
Wei-Lun Chang ◽  
Wei-Ying Chen ◽  
Yi-Chun Yeh ◽  
...  
Keyword(s):  
Helicobacter Pylori ◽  
Gastric Ulcer ◽  
Epithelial Cells ◽  
Matrix Metalloproteinases ◽  
Matrix Metalloproteinase ◽  
Immunohistochemical Staining ◽  
Gastric Ulcers ◽  
Matrix Metalloproteinase 1 ◽  
Two Factors ◽  
H Pylori

Background. Two major causes of gastric ulcers areHelicobacter pylori(H. pylori) infection and nonsteroidal anti-inflammatory drug (NSAID) use.Aims. This study aimed to determine if there were different expressions of matrix metalloproteinases (MMPs) and tissue inhibitor of matrix metalloproteinase-1 (TIMP-1) betweenH. pylori-infected and NSAID-related ulcers.Methods. The 126 gastric ulcer patients (H. pyloriinfectedn=46; NSAID relatedn=30; combined with two factorsn=50) provided ulcer and nonulcer tissues for assessment of MMP-3, -7, and -9 and TIMP-1 expression by immunohistochemical staining.Results. Gastric ulcer tissues had significantly higher MMP-3, -7, and -9 and TIMP-1 expressions than nonulcer tissues (P<0.05).H. pylori-infected gastric ulcers had even higher MMP-7, MMP-9, and TIMP-1 expressions in epithelial cells than NSAID-related gastric ulcers (P<0.05). In patients with the two combined factors, gastric ulcers expressed similar proportions of antral ulcers and MMP-7 and MMP-9 intensities to NSAID-related gastric ulcers, but lower MMP-9 and TIMP-1 thanH. pylori-infected gastric ulcers (P<0.05).Conclusions. H. pylori-infected gastric ulcers express higher MMP-7, MMP-9, and TIMP-1 than NSAID-related ulcers. In patients with the two combined factors, ulcer location and MMP-7 and MMP-9 intensities are similar to NSAID use.

scholarly journals Role of Gamma Interferon in Helicobacter pylori Induction of Inflammatory Mediators during Murine Infection

2002 ◽  
Vol 70 (6) ◽  
pp. 3295-3299 ◽  
Author(s):  
Marygorret Obonyo ◽  
Donald G. Guiney ◽  
Julia Harwood ◽  
Joshua Fierer ◽  
Sheri P. Cole
Keyword(s):  
Helicobacter Pylori ◽  
Gene Knockout ◽  
Gamma Interferon ◽  
Epithelial Cell Line ◽  
Inos Mrna ◽  
Inflammatory Protein ◽  
Ifn Γ ◽  
H Pylori ◽  
Oxide Synthase

ABSTRACT Gamma interferon (IFN-γ) has been proposed to play an important role in Helicobacter-related gastritis. Using the IFN-γ gene knockout (IFN-γ−/−) mouse model and a murine gastric epithelial cell line, GSM06, we demonstrated that Helicobacter pylori maximally induced macrophage inflammatory protein-2 (MIP-2) and inducible nitric oxide synthase (iNOS) mRNA only in wild-type mice. MIP-2 and iNOS mRNA were also induced by H. pylori in GSM06 cells. Induction of cyclooxygenase 2 mRNA through IFN-γ was demonstrated in GSM06 cells. These data indicate that IFN-γ mediates the induction of MIP-2 and iNOS mRNA expression by H. pylori in mice.

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