3-Pentylcatechol, a Non-Allergenic Urushiol Derivative, Displays Anti-Helicobacter pylori Activity In Vivo

We previously reported that 3-pentylcatechol (PC), a synthetic non-allergenic urushiol derivative, inhibited the growth of Helicobacter pylori in an in vitro assay using nutrient agar and broth. In this study, we aimed to investigate the in vivo antimicrobial activity of PC against H. pylori growing in the stomach mucous membrane. Four-week-old male C57BL/6 mice (n = 4) were orally inoculated with H. pylori Sydney Strain-1 (SS-1) for 8 weeks. Thereafter, the mice received PC (1, 5, and 15 mg/kg) and triple therapy (omeprazole, 0.7 mg/kg; metronidazole, 16.7 mg/kg; clarithromycin, 16.7 mg/kg, reference groups) once daily for 10 days. Infiltration of inflammatory cells in gastric tissue was greater in the H. pylori-infected group compared with the control group and lower in both the triple therapy- and PC-treated groups. In addition, upregulation of cytokine mRNA was reversed after infection, upon administration of triple therapy and PC. Interestingly, PC was more effective than triple therapy at all doses, even at 1/15th the dose of triple therapy. In addition, PC demonstrated synergism with triple therapy, even at low concentrations. The results suggest that PC may be more effective against H. pylori than established antibiotics.

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A Novel 3-Deoxy-d-manno-Octulosonic Acid (Kdo) Hydrolase That Removes the Outer Kdo Sugar of Helicobacter pylori Lipopolysaccharide

Journal of Bacteriology ◽

10.1128/jb.187.10.3374-3383.2005 ◽

2005 ◽

Vol 187 (10) ◽

pp. 3374-3383 ◽

Cited By ~ 34

Author(s):

Christopher Stead ◽

An Tran ◽

Donald Ferguson ◽

Sara McGrath ◽

Robert Cotter ◽

...

Keyword(s):

Helicobacter Pylori ◽

Lipid A ◽

In Vitro Assay ◽

Spectrometric Analysis ◽

Vitro Assay ◽

The Core ◽

H Pylori

ABSTRACT The lipid A domain anchors lipopolysaccharide (LPS) to the outer membrane and is typically a disaccharide of glucosamine that is both acylated and phosphorylated. The core and O-antigen carbohydrate domains are linked to the lipid A moiety through the eight-carbon sugar 3-deoxy-d-manno-octulosonic acid known as Kdo. Helicobacter pylori LPS has been characterized as having a single Kdo residue attached to lipid A, predicting in vivo a monofunctional Kdo transferase (WaaA). However, using an in vitro assay system we demonstrate that H. pylori WaaA is a bifunctional enzyme transferring two Kdo sugars to the tetra-acylated lipid A precursor lipid IVA. In the present work we report the discovery of a Kdo hydrolase in membranes of H. pylori capable of removing the outer Kdo sugar from Kdo2-lipid A. Enzymatic removal of the Kdo group was dependent upon prior removal of the 1-phosphate group from the lipid A domain, and mass spectrometric analysis of the reaction product confirmed the enzymatic removal of a single Kdo residue by the Kdo-trimming enzyme. This is the first characterization of a Kdo hydrolase involved in the modification of gram-negative bacterial LPS.

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SpoT-mediated NapA upregulation promotes oxidative stress-induced Helicobacter pylori biofilm formation and confers multidrug resistance

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.00152-21 ◽

2021 ◽

Author(s):

Yican Zhao ◽

Yuying Cai ◽

Zhenghong Chen ◽

Huanjie Li ◽

Zhengzheng Xu ◽

...

Keyword(s):

Helicobacter Pylori ◽

Multidrug Resistance ◽

Biofilm Formation ◽

Drug Resistant ◽

Low Concentrations ◽

Target Molecules ◽

H Pylori ◽

Insight Into

Recently, there is increased incidence of drug-resistant Helicobacter pylori infection. Biofilm formation confers multidrug resistance to bacteria. Moreover, it has been found that the formation of biofilm on the surface of gastric mucosa is an important reason for the difficulty of eradication of H. pylori. The mechanisms underlying H. pylori biofilm formation in vivo have not been elucidated. Reactive oxygen species (ROS) released by the host immune cells in response to H. pylori infection cannot effectively clear the pathogen. Moreover, the extracellular matrix of the biofilm protects the bacteria against ROS-mediated toxicity. This study hypothesized that ROS can promote H. pylori biofilm formation and treatment with low concentrations of hydrogen peroxide (H2O2) promoted this process in vitro. The comparative transcriptome analysis of planktonic and biofilm-forming cells revealed that the expression of SpoT, a (p)ppGpp (guanosine 3'-diphosphate 5'-triphosphate and guanosine 3',5'-bispyrophosphate) synthetase/hydrolase, is upregulated in H2O2-induced biofilms and that knockout of spoT inhibited H. pylori biofilm formation. Additionally, this study examined the key target molecules involved in SpoT regulation using weighted gene co-expression network analysis. The analysis revealed that neutrophil-activating protein (NapA; HP0243) promoted H2O2-induced biofilm formation and conferred multidrug resistance. Furthermore, vitamin C exhibited anti-H. pylori biofilm activity and downregulated the expression of napA in vitro. These findings provide novel insight into the clearance of H. pylori biofilms.

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l-Serine, d- and l-proline and alanine as respiratory substrates of Helicobacter pylori: correlation between in vitro and in vivo amino acid levels

Microbiology ◽

10.1099/mic.0.26203-0 ◽

2003 ◽

Vol 149 (8) ◽

pp. 2023-2030 ◽

Cited By ~ 37

Author(s):

Kumiko Nagata ◽

Yoko Nagata ◽

Tadashi Sato ◽

Masayuki A. Fujino ◽

Kazuhiko Nakajima ◽

...

Keyword(s):

Amino Acids ◽

Helicobacter Pylori ◽

Oxygen Uptake ◽

Energy Sources ◽

Whole Cells ◽

Low Concentrations ◽

Amino Acid Levels ◽

H Pylori

Helicobacter pylori whole cells showed high rates of oxygen uptake with l-serine and l-proline as respiratory substrates, and somewhat lower rates with d-alanine and d-proline. These respiratory activities were inhibited by rotenone and antimycin A at low concentrations. Since pyruvate was produced from l-serine and d- and l-alanine in whole cells, the respiratory activities with these amino acids as substrates occurred via pyruvate. Whole cells showed 2,6-dichlorophenolindophenol (DCIP)-reducing activities with d- and l-proline and d-alanine as substrates, suggesting that hydrogen removed from these amino acids also participated in oxygen uptake by the whole cells. High amounts of l-proline, d- and l-alanine, and l-serine were present in H. pylori cells, and these amino acids also predominated in samples of human gastric juice. H. pylori seems to utilize d- and l-proline, d-alanine and l-serine as important energy sources in its habitat of the mucous layer of the stomach.

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In Vitro and In Vivo Inhibition of Helicobacter pylori by Lactobacillus casei Strain Shirota

Applied and Environmental Microbiology ◽

10.1128/aem.70.1.518-526.2004 ◽

2004 ◽

Vol 70 (1) ◽

pp. 518-526 ◽

Cited By ~ 188

Author(s):

D. Sgouras ◽

P. Maragkoudakis ◽

K. Petraki ◽

B. Martinez-Gonzalez ◽

E. Eriotou ◽

...

Keyword(s):

Helicobacter Pylori ◽

Lactobacillus Casei ◽

Clinical Isolates ◽

Mucosal Inflammation ◽

Control Group ◽

Study Group ◽

Milk Product ◽

H Pylori

ABSTRACT We studied the potential inhibitory effect of Lactobacillus casei strain Shirota (from the fermented milk product Yakult [Yakult Ltd., Tokyo, Japan]) on Helicobacter pylori by using (i) in vitro inhibition assays with H. pylori SS1 (Sydney strain 1) and nine H. pylori clinical isolates and (ii) the in vivo H. pylori SS1 mouse model of infection over a period of 9 months. In vitro activity against H. pylori SS1 and all of the clinical isolates was observed in the presence of viable L. casei strain Shirota cells but not in the cell-free culture supernatant, although there was profound inhibition of urease activity. In vivo experiments were performed by oral administration of L. casei strain Shirota in the water supply over a period of 9 months to 6-week-old C57BL/6 mice previously infected with H. pylori SS1 (study group; n = 25). Appropriate control groups of H. pylori-infected but untreated animals (n = 25) and uninfected animals given L. casei strain Shirota (n = 25) also were included in the study. H. pylori colonization and development of gastritis were assessed at 1, 2, 3, 6, and 9 months postinfection. A significant reduction in the levels of H. pylori colonization was observed in the antrum and body mucosa in vivo in the lactobacillus-treated study group, as assessed by viable cultures, compared to the levels in the H. pylori-infected control group. This reduction was accompanied by a significant decline in the associated chronic and active gastric mucosal inflammation observed at each time point throughout the observation period. A trend toward a decrease in the anti-H. pylori immunoglobulin G response was measured in the serum of the animals treated with lactobacillus, although this decrease was not significant.

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Enhanced fitness of a Helicobacter pylori babA mutant in a murine model

Infection and Immunity ◽

10.1128/iai.00725-20 ◽

2021 ◽

Author(s):

M. Lorena Harvey ◽

Aung Soe Lin ◽

Lili Sun ◽

Tatsuki Koyama ◽

Jennifer H. B. Shuman ◽

...

Keyword(s):

Helicobacter Pylori ◽

Outer Membrane Proteins ◽

Population Diversity ◽

Fitness Advantage ◽

Neutral Locus ◽

Mutant Strains ◽

Bacterial Fitness ◽

H Pylori

Helicobacter pylori genomes encode >60 predicted outer membrane proteins (OMPs). Several OMPs in the Hop family act as adhesins, but the functions of most Hop proteins are unknown. To identify hop mutant strains that exhibit altered fitness in vivo compared to fitness in vitro , we used a genetic barcoding method that allowed us to track changes in the proportional abundance of H. pylori strains within a mixed population. We generated a library of hop mutant strains, each containing a unique nucleotide barcode, as well as a library of control strains, each containing a nucleotide barcode in an intergenic region predicted to be a neutral locus unrelated to bacterial fitness. We orogastrically inoculated each of the libraries into mice and analyzed compositional changes in the populations over time in vivo compared to changes detected in the populations during library passage in vitro . The control library proliferated as a relatively stable community in vitro, but there was a reduction in the population diversity of this library in vivo and marked variation in the dominant strains recovered from individual animals, consistent with the existence of a non-selective bottleneck in vivo . We did not identify any OMP mutants exhibiting fitness defects exclusively in vivo without corresponding fitness defects in vitro . Conversely, a babA mutant exhibited a strong fitness advantage in vivo but not in vitro . These findings, when taken together with results of other studies, suggest that production of BabA may have differential effects on H. pylori fitness depending on the environmental conditions.

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Lactobacillus johnsonii La1 Attenuates Helicobacter pylori-Associated Gastritis and Reduces Levels of Proinflammatory Chemokines in C57BL/6 Mice

Clinical and Diagnostic Laboratory Immunology ◽

10.1128/cdli.12.12.1378-1386.2005 ◽

2005 ◽

Vol 12 (12) ◽

pp. 1378-1386 ◽

Cited By ~ 56

Author(s):

Dionyssios N. Sgouras ◽

Effrosini G. Panayotopoulou ◽

Beatriz Martinez-Gonzalez ◽

Kalliopi Petraki ◽

Spyros Michopoulos ◽

...

Keyword(s):

Helicobacter Pylori ◽

Lamina Propria ◽

Serum Levels ◽

Favorable Effect ◽

Lactobacillus Johnsonii ◽

Ags Cells ◽

Inflammatory Infiltration ◽

H Pylori

ABSTRACT In clinical settings, Lactobacillus johnsonii La1 administration has been reported to have a favorable effect on Helicobacter pylori-associated gastritis, although the mechanism remains unclear. We administered, continuously through the water supply, live La1 to H. pylori-infected C57BL/6 mice and followed colonization, the development of H. pylori-associated gastritis in the lamina propria, and the levels of proinflammatory chemokines macrophage inflammatory protein 2 (MIP-2) and keratinocyte-derived cytokine (KC) in the serum and gastric tissue over a period of 3 months. We documented a significant attenuation in both lymphocytic (P = 0.038) and neutrophilic (P = 0.003) inflammatory infiltration in the lamina propria as well as in the circulating levels of anti-H. pylori immunoglobulin G antibodies (P = 0.003), although we did not observe a suppressive effect of La1 on H. pylori colonizing numbers. Other lactobacilli, such as L. amylovorus DCE 471 and L. acidophilus IBB 801, did not attenuate H. pylori-associated gastritis to the same extent. MIP-2 serum levels were distinctly reduced during the early stages of H. pylori infection in the La1-treated animals, as were gastric mucosal levels of MIP-2 and KC. Finally, we also observed a significant reduction (P = 0.046) in H. pylori-induced interleukin-8 secretion by human adenocarcinoma AGS cells in vitro in the presence of neutralized (pH 6.8) La1 spent culture supernatants, without concomitant loss of H. pylori viability. These observations suggest that during the early infection stages, administration of La1 can attenuate H. pylori-induced gastritis in vivo, possibly by reducing proinflammatory chemotactic signals responsible for the recruitment of lymphocytes and neutrophils in the lamina propria.

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Therapeutic effects of Zuojin Pill on Helicobacter pylori-induced chronic atrophic gastritis through JMJD2B/COX-2/VEGF signaling axis

10.21203/rs.3.rs-20652/v2 ◽

2020 ◽

Author(s):

Shihua Wu ◽

Chunmei Bao ◽

Ruilin Wang ◽

Xiaomei Zhang ◽

Sijia Gao ◽

...

Keyword(s):

Helicobacter Pylori ◽

Cell Viability ◽

Atrophic Gastritis ◽

Chronic Atrophic Gastritis ◽

Gastric Mucosal Damage ◽

Therapeutic Effects ◽

Cox 2 ◽

H Pylori

Abstract Background: Zuojin Pill (ZJP), a famous Chinese medicinal formula, widely accepted for treatment of chronic atrophic gastritis (CAG) in China. This study aimed to explore the therapeutic effects and mechanisms of ZJP in Helicobacter pylori (H. pylori) - induced chronic atrophic gastritis (CAG) in vivo and in vitro. Methods: CAG rat model was induced by H. pylori. ZJP (0.63, 1.26, and 2.52 g/kg, respectively) was administered orally for four weeks. Therapeutic effects of ZJP were identified by H&E staining and serum indices. In addition, cell viability, morphology and proliferation were detected by cell counting kit-8 (CCK8) and high-content screening assay (HCS), respectively. Moreover, relative mRNA expression and protein expression related to JMJD2B/COX-2/VEGF axis was detected to investigate the potential mechanisms of ZJP in CAG. Results: Results showed the symptoms (weight loss and gastric mucosa damage) of CAG were alleviated, and the contents of TNF-α in serum was markedly decreased after treating with ZJP. Moreover, cell viability, proliferation and morphology changes of GES-1 cells were ameliorated by ZJP intervention. In addition, proinflammatory genes and JMJD2B/COX-2/VEGF axis related genes were suppressed by ZJP administration in vitro and in vivo. Meanwhile, immunohistochemistry (IHC) and western blot confirmed down-regulation of these genes by ZJP intervention. Conclusion: ZJP treatment can alleviate gastric mucosal damage induced by H. pylori via JMJD2B/COX-2/VEGF axis.

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Detection of High Titers of Antibody against Helicobacter Cysteine-Rich Proteins A, B, C, and E in Helicobacter pylori-Infected Individuals

Clinical and Diagnostic Laboratory Immunology ◽

10.1128/cdli.10.4.542-545.2003 ◽

2003 ◽

Vol 10 (4) ◽

pp. 542-545 ◽

Cited By ~ 12

Author(s):

Peer R. E. Mittl ◽

Lucas Lüthy ◽

Christoph Reinhardt ◽

Hellen Joller

Keyword(s):

Helicobacter Pylori ◽

Immune System ◽

Control Group ◽

Clear Correlation ◽

Weak Correlation ◽

The Family ◽

Genome Level ◽

Immunological Assays ◽

H Pylori

ABSTRACT The family of Helicobacter cysteine-rich proteins (Hcp) constitutes one of the largest protein families that are specific for proteobacteria from the delta/epsilon subgroup. Most of the proteins belonging to this family have so far only been recognized on the genome level. To investigate the expression of Hcp proteins in vivo we analyzed titers of antibody against HcpA (HP0211), HcpB (HP0336), HcpC (HP1098), and HcpE (HP0235) in sera from 30 Helicobacter pylori-positive individuals and in a control group of six H. pylori-negative individuals. Significantly higher titers of antibody were observed for H. pylori-positive individuals (P < 0.00005). The highest and lowest titers were observed for HcpC (Δ mean = 1.06) and HcpB (Δ mean = 0.333), respectively. There is a clear correlation among anti-HcpA, -HcpC, and -HcpE immunoglobulin G titers in H. pylori-positive individuals (correlation > 0.7), but there is only a weak correlation for HcpB (correlation < 0.4). These results confirm that Hcp proteins are expressed by H. pylori under natural environmental conditions and that these proteins are recognized by the immune system of the host. The observed correlations are in agreement with the expected distribution of Hcp proteins among H. pylori strains. HcpA, HcpC, and HcpE are present in the genomes of strains 26695 and J99, whereas HcpB is absent from most strains. Since Hcp proteins are specific for H. pylori, immunological assays including Hcp proteins might be of value to detect H. pylori infection and perhaps to distinguish among different groups of H. pylori-positive patients.

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Helicobacter pylori Containing Only Cytoplasmic Urease Is Susceptible to Acid

Infection and Immunity ◽

10.1128/iai.66.11.5060-5066.1998 ◽

1998 ◽

Vol 66 (11) ◽

pp. 5060-5066 ◽

Cited By ~ 49

Author(s):

Partha Krishnamurthy ◽

Mary Parlow ◽

Jason B. Zitzer ◽

Nimish B. Vakil ◽

Harry L. T. Mobley ◽

...

Keyword(s):

Helicobacter Pylori ◽

Urease Activity ◽

Acid Resistance ◽

Etiologic Agent ◽

Stationary Phase Culture ◽

Colonization Factor ◽

Acid Environment ◽

H Pylori

ABSTRACT Helicobacter pylori, an important etiologic agent in a variety of gastroduodenal diseases, produces large amounts of urease as an essential colonization factor. We have demonstrated previously that urease is located within the cytoplasm and on the surface of H. pylori both in vivo and in stationary-phase culture. The purpose of the present study was to assess the relative contributions of cytoplasmic and surface-localized urease to the ability of H. pylori to survive exposure to acid in the presence of urea. Toward this end, we compared the acid resistance in vitro of H. pylori cells which possessed only cytoplasmic urease to that of bacteria which possessed both cytoplasmic and surface-localized or extracellular urease. Bacteria with only cytoplasmic urease activity were generated by using freshly subcultured bacteria or by treating repeatedly subcultured H. pylori with flurofamide (1 μM), a potent, but poorly diffusible urease inhibitor. H. pyloriwith cytoplasmic and surface-located urease activity survived in an acid environment when 5 mM urea was present. In contrast, H. pylori with only cytoplasmic urease shows significantly reduced survival when exposed to acid in the presence of 5 mM urea. Similarly,Escherichia coli SE5000 expressing H. pyloriurease and the Ni2+ transport protein NixA, which expresses cytoplasmic urease activity at levels similar to those in wild-typeH. pylori, survived minimally when exposed to acid in the presence of 5 to 50 mM urea. We conclude that cytoplasmic urease activity alone is not sufficient (although cytoplasmic urease activity is likely to be necessary) to allow survival of H. pyloriin acid; the activity of surface-localized urease is essential for resistance of H. pylori to acid under the assay conditions used. Therefore, the mechanism whereby urease becomes associated with the surface of H. pylori, which involves release of the enzyme from bacteria due to autolysis followed by adsorption of the enzyme to the surface of intact bacteria (“altruistic autolysis”), is essential for survival of H. pylori in an acid environment. The ability of H. pylori to survive exposure to low pH is likely to depend on a combination of both cytoplasmic and surface-associated urease activities.

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Discovery and Validation of Novel Methylation Markers in Helicobacter pylori-Associated Gastric Cancer

Disease Markers ◽

10.1155/2021/4391133 ◽

2021 ◽

Vol 2021 ◽

pp. 1-11

Author(s):

Huan Wang ◽

Nian-Shuang Li ◽

Cong He ◽

Chuan Xie ◽

Yin Zhu ◽

...

Keyword(s):

Gene Expression ◽

Gastric Cancer ◽

Dna Methylation ◽

Helicobacter Pylori ◽

Gene Expression Data ◽

Functional Enrichment ◽

Expression Data ◽

H Pylori

Previous studies have shown that abnormal methylation is an early key event in the pathogenesis of most human cancers, contributing to the development of tumors. However, little attention has been given to the potential of DNA methylation patterns as markers for Helicobacter pylori- (H. pylori-) associated gastric cancer (GC). In this study, an integrated analysis of DNA methylation and gene expression was conducted to identify some potential key epigenetic markers in H. pylori-associated GC. DNA methylation data of 28 H. pylori-positive and 168 H. pylori-negative GC samples were compared and analyzed. We also analyzed the gene expression data of 18 H. pylori-positive and 145 H. pylori-negative GC cases. Finally, the results were verified by in vitro and in vivo experiments. A total of 5609 differentially methylated regions associated with 2454 differentially methylated genes were identified. A total of 228 differentially expressed genes were identified from the gene expression data of H. pylori-positive and H. pylori-negative GC cases. The screened genes were analyzed for functional enrichment. Subsequently, we obtained 28 genes regulated by methylation through a Venn diagram, and we identified five genes (GSTO2, HUS1, INTS1, TMEM184A, and TMEM190) downregulated by hypermethylation. HUS1, GSTO2, and TMEM190 were expressed at lower levels in GC than in adjacent samples ( P < 0.05 ). Moreover, H. pylori infection decreased HUS1, GSTO2, and TMEM190 expression in vitro and in vivo. Our study identified HUS1, GSTO2, and TMEM190 as novel methylation markers for H. pylori-associated GC.

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