Gastric pathology associated with Helicobacter pylori

An insight into the anti-ulcerogenic potentials of medicinal herbs and their bioactive metabolites

ETHNOPHARMACOLOGICAL RELEVANCE

Peptic ulcer disease (PUD) ranks top among the most prominent gastrointestinal problems prevalent around the world. Long-term use of non-steroidal anti-inflammatory drugs, pathogenic infection by Helicobacter pylori, imbalances between gastrointestinal regulatory factors and pathological hyperacidity are major contributors towards the development of peptic ulcers. Although synthetic drugs of multiple pharmacological classes are abundantly available, inadequacy of such agents in ensuring complete recovery in not uncommon. Therefore, pharmacological explorations of herbal products including plant extracts and their respective isolated phytoconstituents, for potential gastroprotective and antiulcer properties, are regular practice among the scientific community. Moreover, the historical preferences of a significant share of world population towards herbal-based medication over modern synthetic drugs also contribute significantly to such endeavors.

AIM OF THE REVIEW

This review has endeavored to present ethnomedicinal and pharmacological prospects of a significant number of authenticated plant species in terms of their capacity to exert gastroprotection and antiulcer activities both in vitro and in vivo. The information delineated along the way was further subjected to critical analysis to ascertain the possible future prospects of such findings into designing plant-derived products in future for the treatment of peptic ulcer.

MATERIALS AND METHODS

Electronic version of prominent bibliographic databases, including Google Scholar, PubMed, Scopus, ScienceDirect, Wiley Online Library, SpringerLink, Web of Science, and MEDLINE were explored extensively for the identification and compilation of relevant information. The plant names and respective family names were verified through the Plant List (version 1.1) and World Flora Online 2021. All relevant chemical structures were verified through PubChem and SciFinder databases and illustrated with ChemDraw Ultra 12.0.

RESULTS

A colossal number of 97 plant species categorized under 58 diverse plant families have been discussed in the review for their gastroprotective and antiulcer properties. In vivo illustrations of the pharmacological properties were achieved for almost all the species under consideration. 29 individual phytoconstituents from these sources were also characterized with similar pharmacological potentials. Majority of the plant extracts as well as their constituents were found to exert their gastroprotective effects through antioxidative pathway featuring both enzymatic and nonenzymatic mechanism. Moreover, active inhibition of acid secretion, upregulation of gastroprotective mediators and downregulation of pro-inflammatory cytokines, were also associated with a prominent number of plants or products thereof.

CONCLUSIONS

Comparative evaluations of the plant sources for their antiulcer activities, both as individual and as combination formulations, are necessary to be conducted in human subjects under properly regulated clinical conditions. Moreover, the efficacy and safety of such products should also be evaluated against those of the currently available treatment options. This will further facilitate in ascertaining their suitability and superiority, if any, in the treatment of peptic ulcer diseases. Implementation of these endeavors may eventually lead to development of more efficient treatment options in the future.

Saccharomyces boulardii Allows Partial Patients to Avoid Reusing Bismuth Quadruple for Helicobacter pylori Rescue Therapy: A Single-Center Randomized Controlled Study

Background

The increasing rate of drug resistance often leads to Helicobacter pylori (H. pylori) eradication failure and needs the rescue therapy. Thus, the exploration of new rescue therapeutic regimens is important. The present study was designed to test the beneficial effects of Saccharomyces boulardii (S.boulardii) prior to H. pylori rescue therapy basing on bismuth quadruple.

Methods

One hundred H. pylori-infected patients were randomly divided into two groups: study group and control group. Patients in the study group (n=50) underwent two-stages therapy: patients started with S.boulardii monotherapy for 2 weeks, and then tested for H. pylori infection after resting for 4 weeks without any therapy, patients who were still positive for H. pylori continued with bismuth quadruple eradication therapy. For the control group (n=50), all patients were observed and were not treated with any gastric drugs or antibiotics for 6 weeks, then those who were still positive for H. pylori received the same eradication therapy as the study group. Eradication rate, adverse events and the cost-effectiveness of two regimens were analyzed in this study.

Results

The H.pylori eradication rate of ITT (intent-to-treat) analysis and PP (per-protocol) analysis in the first phase of treatment were significantly higher in the study group than the control groups respectively (28.0% vs 2.0%, p<0.001 and 30.4% vs 2.1% p<0.001). For the total treatment effect, there were no significant differences in the eradication rate of ITT analysis (78.0% vs 80.0%) or PP analysis (90.7% vs 88.9%) between the study group and the control group. The cost‐effectiveness ratio of the study group was slightly higher than that of the control group (8.95 vs 8.55). There were two patients in the study group and four patients in the control group with the adverse events, respectively. There was no significant difference on the incidence of adverse events between the two groups (p=0.68).

Conclusion

S.boulardii may serve as a beneficial treatment option before H. pylori rescue therapy since it callowed partial patients to avoid reusing bismuth quadruple.

Basic Traditional Chinese Medicinal Compound for Adjuvant Treatment of Helicobacter pylori-Related Gastritis: Implication for Anti-H. pylori-Related Gastritis Drug Discovery

This study was aimed at evaluating the efficacy of traditional Chinese medicine (TCM) in the adjuvant treatment of Helicobacter pylori-associated gastritis (HPAG) and exploring the molecular mechanism underlying the action of the basic TCM compounds against HPAG. Eight representative Chinese and British databases were combed for pertinent literature. In light of the basic principle of evidence-based medicine, this work rigorously stuck to the inclusion and exclusion of criteria so as to plump for qualified articles. Also, the data mining method was adopted to help determine the basic TCM compound for HPAG treatment. Furthermore, a network pharmacology-based strategy was used to uncover the underlying mechanisms of the basic TCM compound against HPAG. Ultimately, molecular docking was used for preliminary verification. TCM combined with triple or quadruple therapy against HPAG possessed more advantages in improving the total effective rate and H. pylori eradication rate than triple or quadruple therapy alone. The basic TCM plant materials against HPAG consisted of Citrus reticulata Blanco, Glycyrrhiza uralensis Fisch, Pinellia ternata (Thunb.) Breit, Coptis chinensis Franch, and Poria cocos (Schw.) Wolf. Quercetin, kaempferol, naringenin, baicalein, nobiletin, and hederagenin were determined as the key active ingredients of the basic TCM preparation against HPAG. Moreover, these ingredients played a therapeutic role by acting on AKT1, TP53, interleukin (IL)-6, VEGFA, CASP3, MAPK3, JUN, TNF, and MAPK8 via Pathways in cancer, PI3K-Akt signaling pathway, TNF signaling pathway, and MAPK signaling pathway. The results of molecular docking indicated that the key ingredients could bind stably with the core targets. The efficacy of the TCM in the adjuvant treatment of HPAG is worthy of affirmation. Compatible use of the key ingredients of the basic TCM compound is a novel idea of drug research with profound clinical significance and research value in the development of anti- H. pylori drugs.

HomA and HomB, outer membrane proteins of Helicobacter pylori down-regulate activation-induced cytidine deaminase (AID) and Ig switch germline transcription and thereby affect class switch recombination (CSR) of Ig genes in human B-cells

H. pylori is one of the major causes of chronic gastritis, peptic ulcer disease (PUD), gastric mucosa-associated lymphoid tissue lymphoma (MALT) and gastric carcinoma. H. pylori toxin VacA is responsible for host cell apoptosis, whereas CagA is known to aberrantly induce expression of activation-induced cytidine deaminase (AID) in gastric epithelial cells that causes mutations in oncogenes and tumour suppressor genes, leading to the transformation of normal cells into cancerous cells. Although, a significant amount of research has been conducted to understand the role of bacterial factors modulating deregulated host cell pathways, the interaction between H. pylori and immune cells of the marginal zone and its consequences are still not well understood. HomB and HomA, outer membrane proteins (OMPs) from H. pylori, which assist in the adhesion of bacteria to host cells, are found to be associated with H. pylori virulent strains and promote inflammation. Interestingly, we observed that the interaction of HomB/HomA OMPs with B-cells transiently downregulates AID expression and Ig switch germline transcription. Downregulation of AID leads to impairment of class switch recombination (CSR), resulting in significantly reduced switching to IgG and IgA antibodies. Besides, we examined the immune-suppressive response of B-cells and observed that the cells stimulated with HomA/B show upregulation in the levels of IL10, IL35, as well as PDL1, a T-cell inhibition marker. Our study suggests the potential role of OMPs in immune response modulation strategies used by the pathogen to evade the immune response. These results provide a better understanding of H. pylori pathogenesis and assist in identifying novel targets for therapy.

Temperatures Outside the Optimal Range for Helicobacter pylori Increase Its Harboring within Candida Yeast Cells

Simple Summary

Helicobacter pylori is associated with the development of diverse gastric pathologies. This bacterium has been shown to invade yeast to protect itself from environmental factors such as changes in pH, the presence of antibiotics or variations in nutrients that affect their viability. However, intra-yeast H. pylori has been reported from other sources, including food, or when the storage temperature is outside the optimal growth range for H. pylori, which is 30–37 °C. It is necessary to continue investigating the environmental factors that participate in the entry of the bacteria into yeast. In this work, it was evaluated whether temperature changes promote the entry of H. pylori into Candida and whether this endosymbiosis favors bacterial viability. It was observed that H. pylori significantly increased its invasiveness to yeast when these two microorganisms were co-cultured under 40 °C. The results support that H. pylori invades yeasts to protect itself from stressful environments, favoring its viability in these environments. In addition, it can be suggested that this microorganism would use yeast as a transmission vehicle, thereby contributing to its dissemination in the population. However, the latter still needs to be confirmed.

Abstract

Helicobacter pylori is capable of entering into yeast, but the factors driving this endosymbiosis remain unknown. This work aimed to determine if temperatures outside the optimal range for H. pylori increase its harboring within Candida. H. pylori strains were co-cultured with Candida strains in Brucella broth supplemented with 5% fetal bovine serum and incubated at 4, 25, 37 or 40 °C. After co-culturing, yeasts containing bacteria-like bodies (Y-BLBs) were observed by optical microscopy, and the bacterium were identified as H. pylori by FISH. The H. pylori 16S rRNA gene was amplified from the total DNA of Y-BLBs. The viability of intra-yeast H. pylori cells was confirmed using a viability assay. All H. pylori strains were capable of entering into all Candida strains assayed. The higher percentages of Y-BLBs are obtained at 40 °C with any of the Candida strains. H pylori also increased its harboring within yeast in co-cultures incubated at 25 °C when compared to those incubated at 37 °C. In conclusion, although H. pylori grew significantly at 40 °C, this temperature increased its harboring within Candida. The endosymbiosis between both microorganisms is strain-dependent and permits bacterial cells to remain viable under the stressing environmental conditions assayed.

Carbonic Anhydrases: New Perspectives on Protein Functional Role and Inhibition in Helicobacter pylori

Our understanding of the function of bacterial carbonic anhydrases (CAs, EC 4.2.1.1) has increased significantly in the last years. CAs are metalloenzymes able to modulate CO₂, HCO₃ ^- and H⁺ concentration through their crucial role in catalysis of reversible CO₂ hydration (CO₂ + H₂O ⇄ HCO₃ ^- + H⁺). In all living organisms, CA activity is linked to physiological processes, such as those related to the transport and supply of CO₂ or HCO₃ ^-, pH homeostasis, secretion of electrolytes, biosynthetic processes and photosynthesis. These important processes cannot be ensured by the very low rate of the non-catalyzed reaction of CO₂ hydration. It has been recently shown that CAs are important biomolecules for many bacteria involved in human infections, such as Vibrio cholerae, Brucella suis, Salmonella enterica, Pseudomonas aeruginosa, and Helicobacter pylori. In these species, CA activity promotes microorganism growth and adaptation in the host, or modulates bacterial toxin production and virulence. In this review, recent literature in this research field and some of the above-mentioned issues are discussed, namely: (i) the implication of CAs from bacterial pathogens in determining the microorganism growth and virulence; (ii) the druggability of these enzymes using classical CA inhibitors (CAIs) of the sulfonamide-type as examples; (iii) the role played by Helicobacter pylori CAs in the acid tolerance/adaptation of the microbe within the human abdomen; (iv) the role of CAs played in the outer membrane vesicles spawned by H. pylori in its planktonic and biofilm phenotypes; (v) the possibility of using H. pylori CAIs in combination with probiotic strains as a novel anti-ulcer treatment approach. The latter approach may represent an innovative and successful strategy to fight gastric infections in the era of increasing resistance of pathogenic bacteria to classical antibiotics.

Helicobacter pylori healthy South Asians

We aimed to estimate the pooled prevalence of Helicobacter pylori among asymptomatic South Asians based on available literature and highlight the importance of screening asymptomatic individuals and implementing preventive strategies for eradicating H. pylori. Electronic databases such as PubMed and Embase, a regional database of WHO South Asian Region, and gray literature sites were searched for relevant studies from 1983 to 5 May 2020. In addition, references of the included studies were thoroughly searched. The random-effect model was used to calculate the pooled prevalence with a 95% confidence interval (CI) along with subgroup analysis. Analysis of 19 studies showed a pooled prevalence of 56.5%, ranging from 10.3 to 91.7%. In subgroup analysis by country, the highest prevalence rate was reported from Bangladesh (86.3%, 95% CI: 0.806-0.921), whereas the lowest prevalence was from Sri Lanka (10.3%, 95% CI: 0.072-0.135). No differences were found between males and females. Prevalence among children and adolescents was 65.3% (95% CI: 0.529-0.777), greater than adults, 56.9% (95% CI: 0.353-0.785). The prevalence rate showed a decreasing trend upon comparison of studies conducted before and after 2000. Our analysis reveals the high prevalence of H. pylori infection among asymptomatic healthy populations in South Asia, particularly in children and adolescents. Public health awareness and sanitation interventions, pure drinking water, and respective strategies on a policy level to eradicate H. pylori and additional extensive multicentric cohort studies are necessary.

ABH and Lewis blood group systems and their relation to diagnosis and risk of Helicobacter pylori infection

BACKGROUND

Helicobacter pylori infection occurs in 50% of the world's population and represents a major risk factor for chronic gastritis, gastroduodenal ulcer and gastric cancer in developed and developing countries. The distribution of H. pylori virulence factors is diverse and varies geographically, such as the CagA and VacA genes, which have revealed association with disease status. Some findings show increased frequencies of these diseases in O Le (a-b +) and A Le (a-b +) blood type individuals, but other studies not found any relationship between these blood groups and H. pylori infection.

AIM

This study aimed to elucidate probable controversies described in the relationship between the ABH/Lewis blood groups and H. pylori, contributing to the severity of gastric diseases in northern the population of Belém -Pará.-Brazil.

METHODS

This cross-sectional study included 288 samples of patients separate into two groups with gastric cancer and chronic gastritis. Blood, saliva, and gastric biopsy were analyzed using modified Gram and hematoxylin-eosin staining techniques, the enzyme immunoassay Elisa and Multiplex PCR. The antigens expression of ABH and Lewis systems was determined through Dot-ELISA and direct hemagglutination. Proportions were compared in univariate analysis, while the relation between putative risk factors including H. pylori status and ABO/Lewis phenotype was performed using multivariable logistic regression analyses, P-value < 0.05 was considered significant.

RESULTS

The findings of this study demonstrate that the likelihood of developing gastric cancer increases threefold if the individual is from A1 Le (a-b +) blood group, has premalignant changes, and infection with H. pylori virulent strains (cagA+/vacA + s1m1).

CONCLUSION

Therefore, this study found a significant association between ABO and Lewis phenotypes and H. pylori cagA status into the relevance of the development of gastric carcinogenesis.

The promise and challenge of cancer microbiome research

Many microbial agents have been implicated as contributors to cancer genesis and development, and the search to identify and characterize new cancer-related organisms is ongoing. Modern developments in methodologies, especially culture-independent approaches, have accelerated and driven this research. Recent work has shed light on the multifaceted role that the community of organisms in and on the human body plays in cancer onset, development, detection, treatment, and outcome. Much remains to be discovered, however, as methodological variation and functional testing of statistical correlations need to be addressed for the field to advance.

Cost-Effectiveness Analysis of Helicobacter pylori Eradication Therapy for Prevention of Gastric Cancer: A Markov Model

BACKGROUND

Helicobacter pylori (H. pylori) eradication can reduce the prevalence of gastric cancer. However, whether H. pylori eradication therapy should be performed in infected patients, especially in asymptomatic cases, is still controversial.

AIMS

The aims of this study were to determine whether H. pylori screening and eradication could prevent gastric cancer in a cost-effective way, and further whether eradication therapy should be administered to asymptomatic individuals.

METHODS

Cost-effectiveness analysis was performed using a Markov model. We established two groups, each with 10,000 hypothetical Chinese individuals at the age of 40 years. Clinical outcomes and cost of H. pylori eradication were compared between the eradication and control groups.

RESULTS

There was a lower morbidity with gastric cancer in the eradication group than in the control group, which was most significant after running the model for 15 years. The eradication group experienced an average of 34.64 quality-adjusted life years (QALYs) per person, and the average cost was US $1706.52 per person. The control group exhibited an average of 32.63 QALYs per person, and the average cost was US $2045.10 per person. The cost-effectiveness analysis showed that eradication saved $1539 per LY per person and $168.45 per QALY per person.

CONCLUSIONS

H. pylori screening and eradication therapy effectively reduces the morbidity of gastric cancer and cancer-related costs in asymptomatic infected individuals. Therefore, we believe that H. pylori eradication can prevent gastric cancer in a cost-effective way.

Significance of TC9 and TH9 in Helicobacter pylori-induced gastritis

BACKGROUND

H pylori plays a critical role in the development of stomach cancer, especially in people affected by the bacteria at an early stage of life. Th9 cells and IL-9 play major roles in immune responses against various infections. IL-9 is influential in chronic or acute inflammation of the mucosa.

AIM

This study seeks to investigate the possible functions of Tc9, Th9 cells, and IL-9 level in patients with inflammation due to H pylori infection.

METHODS

Eighty-three patients with dyspepsia symptoms and twenty normal subjects with no sign and symptoms of dyspepsia were recruited. Frequencies of T-cell subsets were determined by flow cytometry. Levels of cytokines IL-9 family in the sera and supernatants of antigen-activated PBMCs patients were measured by ELISA and flow cytometry.

RESULTS

The participants included 56 females and 47 males with a mean age of 39.2 ± 15.3 years. We assigned the infected group into peptic ulcer and gastritis (chronic active and chronic). Frequencies of Tc9, Th17, Tc17, Th17/9, and Tc17/9 increased significantly in the peptic ulcer, chronic active, and chronic gastritis, compared with the uninfected and healthy control groups. A significant increase was seen in IL-9, IL-4, and IL-23 in the chronic active gastritis. Further observed was a significant increase in IL-21 and a decrease in IL-10 in the infected groups.

CONCLUSION

The results revealed that increased Tc9, Th17/9, and Tc17/9 cells appear to be influential in the progression and severity of H pylori infection. Also, increased IL-9 and IL-4 levels and Tc9, Tc17/9, and Th17/9 were seen in chronic active gastritis patients. These findings may provide useful information for a therapeutic targeting of chronic active H pylori infections.

Interleukin-32: Frenemy in cancer?

Interleukin-32 (IL-32) was originally identified in natural killer (NK) cells activated by IL-2 in 1992. Thus, it was named NK cell transcript 4 (NK4) because of its unknown function at that time. The function of IL-32 has been elucidated over the last decade. IL-32 is primarily considered to be a booster of inflammatory reactions because it is induced by pro-inflammatory cytokines and stimulates the production of those cytokines and vice versa. Therefore, many studies have been devoted to studying the roles of IL-32 in inflammation-associated cancers, including gastric, colon cancer, and hepatocellular carcinoma. At the same time, roles of IL-32 have also been discovered in other cancers. Collectively, IL-32 fosters the tumor progression by nuclear factor-κB (NF-κB)-mediated cytokines and metalloproteinase production, as well as stimulation of differentiation into immunosuppressive cell types in some cancer types. However, it is also able to induce tumor cell apoptosis and enhance NK and cytotoxic T cell sensitivity in other cancer types. In this review, we will address the function of each IL-32 isoform in different cancer types studied to date, and suggest further strategies to comprehensively elucidate the roles of IL-32 in a context-dependent manner.

Systematic review: Would susceptibility-guided treatment achieve acceptable cure rates for second-line Helicobacter pylori therapy as currently practiced?

BACKGROUND

Susceptibility-guided treatment has been proposed as a way to improve Helicobacter pylori eradication rates. Evidence on its efficacy for rescue therapy is very scarce. The aim of this study was to indirectly assess the applicability and effectiveness of susceptibility-guided treatment by evaluating (a) the rate of acceptance of endoscopy, (b) its success in detecting resistances, and (c) infection cure rates in patients harboring strains found to be susceptible to the antibiotics administered in clinical trials in which the efficacy of second-line treatments was reported.

METHODS

A systematic review of studies evaluating second-line H pylori treatment was carried out in multiple databases. Studies reporting antibiotic susceptibility evaluation and/or cure rates in patients harboring sensitive and resistant strains were selected. Data were extracted in duplicate.

RESULTS

The systematic review identified 36 eligible studies. Acceptance was evaluated in only one study of 60 patients, of whom only 38 agreed to endoscopy. Among the 2890 patients who received endoscopy and culture, resistances were finally determined in 86.5%. Cure rate was 72.5% in the 113 patients harboring a clarithromycin-susceptible strain after previous clarithromycin treatment, 93.5% in the 765 patients harboring a metronidazole-susceptible strain, and 83.8% in the 192 patients harboring a levofloxacin-susceptible strain. No studies with repeated administration of levofloxacin or metronidazole were found.

CONCLUSION

Even if the culture shows a clarithromycin-sensitive strain, repeating clarithromycin after a first failure should be discouraged. Susceptibility-guided treatment alone did not achieve adequate cure rates for rescue therapies. Additional measures are needed to design rescue treatments that consistently achieve excellent cure rates.

Gastric Microbiota in Helicobacter pylori-Negative and -Positive Gastritis Among High Incidence of Gastric Cancer Area

Helicobacter pylori (H. pylori) related chronic gastritis is a well-known major etiological factor for gastric cancer development. However, H. pylori-negative gastritis (HpN) is not well described. We aimed to examine gastric mucosal microbiota in HpN compared to H. pylori-positive gastritis (HpP) and H. pylori-negative non-gastritis group (control). Here, we studied 11 subjects with HpN, 40 with HpP and 24 controls. We performed endoscopy with six gastric biopsies. Comparison groups were defined based on strict histological criteria for the disease and H. pylori diagnosis. We used 16S rRNA gene amplicon sequencing to profile the gastric microbiota according to comparison groups. These results demonstrate that the HpP group had significantly lower bacterial richness by the operational taxonomic unit (OTU) counts, and Shannon and Simpson indices as compared to HpN or controls. The linear discriminant analysis effect size analysis showed the enrichment of Firmicutes, Fusobacteria, Bacteroidetes and Actinobacteria at phylum level in the HpN group. In the age-adjusted multivariate analysis, Streptococcus sp. and Haemophilus parainfluenzae were at a significantly increased risk for HpN (odds ratio 18.9 and 12.3, respectively) based on abundance. Treponema sp. was uniquely found in HpN based on occurrence. In this paper, we conclude that Streptococcus sp., Haemophilus parainfluenzae and Treponema sp. are candidate pathogenic bacterial species for HpN. These results if confirmed may have important clinical implications.

Analysis of key genes and signaling pathways involved in Helicobacter pylori-associated gastric cancer based on The Cancer Genome Atlas database and RNA sequencing data

BACKGROUND

Helicobacter pylori (H. pylori) infection is associated with the development of gastric cancer, although the mechanism is unclear. Herein, this study aimed to clarify the key genes and signaling pathways involved in H. pylori pathogenesis based on The Cancer Genome Atlas (TCGA) database and RNA sequencing analysis.

MATERIALS AND METHODS

Forty-nine gastric cancer samples (16 with H. pylori and 33 without H. pylori) and 35 cancer-adjacent normal samples from TCGA database were analyzed by bioinformatics. The differentially expressed genes between H. pylori-positive and H. pylori-negative patients were verified in 18 gastric cancer (GC) samples (9 with H. pylori and 9 without H. pylori), which were analyzed using RNA sequencing. Survival analysis was carried out to explore associations between the differentially expressed genes and prognosis. Bioinformatics analysis was performed to determine the signaling pathways associated with H. pylori.

RESULTS

The baseline level of clinical features from TCGA database and RNA sequencing showed no differences between the H. pylori-positive and H. pylori-negative GC groups (P > 0.05). TP53 was shown to be upregulated in the H. pylori-positive group in both TCGA database and RNA sequencing data, which also showed higher expression in the GC tissues than in adjacent normal tissues (P < 0.05). CCDC151, CHRNB2, GMPR2, HDGFRP2, and VSTM2L were shown to be downregulated in the H. pylori-positive group by both TCGA database and RNA sequencing, which also showed lower expression in the GC tissues than in adjacent normal tissues (P < 0.05). GC patients with low expression levels of HDGFRP2 had a poor prognosis (P < 0.05). Thirty-three signaling pathways and 10 biological processes were found to be positively associated with H. pylori infection (P < 0.05, FDR < 0.05).

CONCLUSIONS

These results indicate that some genes (TP53, CCDC151, CHRNB2, GMPR2, HDGFRP2, VSTM2L) and previously unidentified signaling pathways (eg, the Hippo signaling pathway) might play an important role in H. pylori-associated GC.

Prevalence of Helicobacter pylori resistance after failure of first-line therapy. A systematic review

There are no systematic data on the rates of antibiotic resistance after the failure of a first eradication treatment. The objective of this study was to determine the prevalence of secondary resistance to antibiotics by conducting a systematic review of studies evaluating the secondary resistance of Helicobacter pylori. We identified 31 studies (2,787 patients). Resistance was determined in 1,764 patients. A percentage of 99.1 of patients received clarithromycin as first-line treatment and 58.7% developed resistance. A percentage of 24.3 received metronidazole and 89.7% developed resistance. Secondary resistance to amoxicillin was extremely rare. Secondary resistance after first-line treatment was very common. These findings support the recommendation not to repeat clarithromycin or metronidazole after the failure of a first eradication treatment.

A comparative study on Helicobacter pylori infection in Tibetan and Han people from Tibet and Sichuan province

AIM

To compare the prevalence of Helicobacter pylori (H. pylori) infection in Tibetan and Han subjects from Tibet and Sichuan province.

METHODS

A retrospective study for investigating H. pylori infection was performed among Tibetan and Han subjects who underwent the ¹⁴C-urea breath test at the Tibetan Chengdu Branch Hospital and West China Hospital. The clinical characteristics (residential address, H. pylori infection status, etc.) were collected and recorded.

RESULTS

A total of 2163 subjects from Tibet (Tibetan/Han, 547/297) and Sichuan province (Tibetan/Han, 308/1011) were enrolled in this retrospective study. The overall H. pylori positive rate in Tibet was significantly lower than that in Sichuan province (50.8% vs 39.3%, P < 0.001). The H. pylori positive rate in Tibetan subjects from both Tibet and Sichuan was significantly higher than that in Han people (56.9% vs 39.7%, P < 0.001; 52.3% vs 35.4%, P < 0.001). No significant difference was observed in the H. pylori positive rate between Tibetan subjects from Tibet and Sichuan (P = 0.196) or Han subjects from Tibet and Sichuan (P = 0.192). The H. pylori positive rate of Han ethnic subjects significantly increased in the older age group (age < 45 vs age ≥ 45: 32.3% vs 40.5%, P = 0.002). However, the H. pylori positive rate of Tibetan subjects significantly decreased in the older age group (age < 45 vs age ≥ 45: 61.5% vs 50.0%, P = 0.001).

CONCLUSION

The H. pylori prevalence rate is higher in Tibetan subjects than in Han subjects from Sichuan province and Tibet. The H. pylori prevalence rate is positively correlated with age in Han subjects, but is negatively correlated with age in Tibetan subjects.

Systematic review, meta-analysis, and meta-regression: Successful second-line treatment for Helicobacter pylori

BACKGROUND

Multiple Helicobacter pylori second-line schedules have been described as potentially useful. It remains unclear, however, which are the best combinations, and which features of second-line treatments are related to better cure rates. The aim of this study was to determine that second-line treatments achieved excellent (>90%) cure rates by performing a systematic review and when possible a meta-analysis. A meta-regression was planned to determine the characteristics of treatments achieving excellent cure rates.

METHODS

A systematic review for studies evaluating second-line Helicobacter pylori treatment was carried out in multiple databases. A formal meta-analysis was performed when an adequate number of comparative studies was found, using RevMan5.3. A meta-regression for evaluating factors predicting cure rates >90% was performed using Stata Statistical Software.

RESULTS

The systematic review identified 115 eligible studies, including 203 evaluable treatment arms. The results were extremely heterogeneous, with 61 treatment arms (30%) achieving optimal (>90%) cure rates. The meta-analysis favored quadruple therapies over triple (83.2% vs 76.1%, OR: 0.59:0.38-0.93; P = .02) and 14-day quadruple treatments over 7-day treatments (91.2% vs 81.5%, OR; 95% CI: 0.42:0.24-0.73; P = .002), although the differences were significant only in the per-protocol analysis. The meta-regression did not find any particular characteristics of the studies to be associated with excellent cure rates.

CONCLUSION

Second-line Helicobacter pylori treatments achieving>90% cure rates are extremely heterogeneous. Quadruple therapy and 14-day treatments seem better than triple therapies and 7-day ones. No single characteristic of the treatments was related to excellent cure rates. Future approaches suitable for infectious diseases-thus considering antibiotic resistances-are needed to design rescue treatments that consistently achieve excellent cure rates.

Fifth Chinese National Consensus Report on the management of Helicobacter pylori infection

BACKGROUND

Since the 'Fourth Chinese National Consensus Report on the management of H. pylori infection' was published in 2012, three important consensuses (Kyoto global consensus report on H. pylori gastritis, The Toronto Consensus for the Treatment of H. pylori Infection in Adults and Management of H. pylori infection-the Maastricht V/Florence Consensus Report) have been published regarding the management of H. pylori infection.

MATERIALS AND METHODS

A Delphi method was adopted to develop the consensus of relevant 'statements'. First, the established 'statements' were sent to experts via email. Second, after undergoing two rounds of consultation, the initial statements were discussed face to face and revised in the conference item by item on 16 December 2016. Finally, 21 core members of conferees participated in the final vote of statements. Voting for each statement was performed using an electronic system with levels of agreements shown on the screen in real time.

RESULTS

Consensus contents contained a total of 48 "statements" and related 6 parts, including indications for H. pylori eradication, diagnosis, treatment, H. pylori and gastric cancer, H. pylori infection in special populations, H. pylori and gastrointestinal microbiota.

CONCLUSIONS

Recommendations are provided on the basis of the best available evidence.

vacA s1m1 genotype and cagA EPIYA-ABC pattern are predominant among Helicobacter pylori strains isolated from Mexican patients with chronic gastritis

Purpose

Virulent genotypes of Helicobacter pylori vacA s1m1/cagA⁺/babA2⁺ have been associated with severe gastric diseases. VacA, CagA and BabA are polymorphic proteins, and their association with the disease is allele-dependent. The aims of this work were: (i) to determine the prevalence of H. pylori by type of chronic gastritis; (ii) to describe the frequency of cagA, babA2 and vacA genotypes in strains from patients with different types of chronic gastritis; (iii) to characterize the variable region of cagA alleles.

Methodology

A total of 164 patients with chronic gastritis were studied. Altogether, 50 H. pylori strains were isolated, and the status of cagA, babA2 and vacA genotypes was examined by PCR. cagA EPIYA segment identification was performed using PCR and sequencing of cagA fragments of six randomly selected strains.

Results/Key findings

The overall prevalence of H. pylori was 30.5 %. Eighty percent of the isolated strains were vacA s1m1, and the cagA and babA2 genes were detected in 74 and 32 % of the strains, respectively. The most frequent genotypes were vacA s1m1/cagA⁺/babA2^- and vacA s1m1/cagA⁺/babA2⁺, with 40 % (20/50) and 28 % (14/50), respectively. In cagA⁺, the most frequent EPIYA motif was -ABC (78.4 %), and EPIYA-ABCC and -ABCCC motifs were found in 10.8 % of the strains. A modified EPIYT-B motif was found in 66.6 % of the sequenced strains.

Conclusion

H. pylori strains carrying vacA s1m1, cagA⁺ and babA2^- genotypes were the most prevalent in patients with chronic gastritis from the south of Mexico. In the cagA⁺ strains, the EPIYA-ABC motif was the most common.

Gastric TFF1 Expression from Acute to Chronic Helicobacter Infection

TFF1, a mucin-associated secreted peptide of gastric mucous cells, is known as a protective agent for stomach epithelium under different stimuli, but its role upon Helicobacter infection is still not clear. In this paper we characterized TFFs expression, with particular attention to TFF1, under Helicobacter infection in gastric cell lines. A mouse model was used to distinguish TFF1 mRNA expression between acute and chronic stages of Helicobacter infection. Our results show that TFF1 expression is induced in infected cells; in addition, the inflammatory response upon Helicobacter infection is inversely associated to pre-existing TFF1 protein levels. In infected mice, TFF1 is initially upregulated in gastric antrum in the acute phase of infection, along with IL-1β and IL-6. Then, expression of TFF1 is gradually silenced when the infection becomes chronic and IFN-γ, CXCL5, and CXCL15 reach higher levels. Our data suggest that TFF1 might help cells to counteract bacteria colonization and the development of a chronic inflammation.

No evidence to support a role for Helicobacter pylori infection and plasminogen binding protein in autoimmune pancreatitis and IgG4-related disease in a UK cohort

BACKGROUND AND OBJECTIVES

Helicobacter pylori (H.pylori) plasminogen binding protein (PBP) has been proposed as an antigen triggering autoimmune pancreatitis (AIP), the pancreatic manifestation of IgG4-related disease (IgG4-RD). We investigated exposure to H. pylori infection, cytokine response and immunological memory to H. pylori PBP in a prospective IgG4-RD cohort in the UK.

METHODS

Clinical and endoscopic evidence of peptic ulceration, serological H. pylori exposure and serum IgG4 levels were obtained in 55 IgG4-RD patients and 52 disease controls (DC) with autoimmune or inflammatory conditions with an elevated serum IgG4. Gastric and duodenal tissues were assessed for H. pylori and immunostained for IgG4. B and T cell ELISpot and cytokine luminex assays were used to detect immune responses to H. pylori PBP.

RESULTS

85% of IgG4-RD patients had pancreatic and/or biliary disease, 89% had extra-pancreatic manifestations, and 84% had an increased serum IgG4. Clinical dyspepsia (35.2%), gastritis (58%), peptic ulceration (7.4%) and H. pylori colonisation (24%) in IgG4-RD was similar to DC. In IgG4-RD, gastric tissue contained a chronic inflammatory infiltrate with a low IgG4+ plasma-cell count (<10/HPF; range 1-4/HPF), and duodenal specimens had an increased IgG4 count (>10/HPF; range 7-54) compared with DC (p < 0.01). Th1 and Th2 cytokine response and immunological B-cell memory to H. pylori PBP did not differ between IgG4-RD and DC.

CONCLUSIONS

In a prospective UK cohort, the prevalence of gastric ulceration, exposure to H. pylori, cytokine response and immunological memory to H. pylori PBP did not differ in IgG4-RD patients compared with DC. This study does not support a role for H. pylori PBP as a microbial antigen in IgG4-RD.

KEYWORDS FOR ABSTRACT

Peptic ulceration, Antigens, B cells, T cells, Interleukins, Helicobacter pylori.

Positive relationship between p42.3 gene and inflammation in chronic non-atrophic gastritis

OBJECTIVE

Gastric cancer (GC) is a typical type of inflammation-related tumor. The p42.3 gene is shown to be highly expressed in GC, but its association with gastritis remains unknown. We aimed to explore the relationship between gastric inflammation and p42.3 gene in vitro and in vivo.

METHODS

Normal gastric epithelial cells (GES-1) were treated with Helicobacter pylori (H. pylori) and tumor necrosis factor (TNF)-α. Total cell mRNA and protein were extracted and collected, and polymerase chain reaction and Western blot were performed to determine the relative expression of p42.3 gene. In total, 291 biopsy samples from patients with chronic non-atrophic gastritis were collected and immunohistochemistry was used to measure the p42.3 protein expression. The association between p42.3 protein expression and the clinicopathological characteristics of these patients were analyzed.

RESULTS

Both H. pylori and TNF-α significantly enhanced the p42.3 protein expression in GES-1 cells in a time and dose-dependent manner. In addition, p42.3 gene expression was positively associated with the severity of gastric mucosal inflammation and H. pylori infection (P = 0.000). Its expression was significantly more common in severe gastric inflammation and in H. pylori-infected cases.

CONCLUSION

p42.3 gene expression is associated with gastric mucosal inflammation that can be upregulated by TNF-α and H. pylori infection.

Synthesis and antimicrobial activity of novel substituted ethyl 2-(quinolin-4-yl)-propanoates

Substituted 4-hydroxyquinolines were synthesized from anilines and diethyl 2-(ethoxymethylene)malonate by the Gould-Jacobs reaction via cyclization of the intermediate anilinomethylenemalonate followed by hydrolysis and decarboxylation. The 4-hydroxyquinolines reacted with phosphorous oxychloride to form 4-chloroquinolines, which reacted on heating with diethyl sodiomethylmalonate in DMF to yield moderate yields of substituted ethyl 2-(quinolin-4-yl)propanoates, many of which showed potent antimicrobial activity against Helicobacter pylori.

Predictive value of neutrophil infiltration as a marker of Helicobacter pylori infection

AIM: To evaluate the predictive value of neutrophil infiltration as a marker of Helicobacter pylori (H. pylori) infection.

METHODS: A total of 315 patients with dyspepsia symptoms who underwent upper gastrointestinal endoscopy were enrolled in this study. Biopsies were evaluated using the updated Sydney system. The medication history of all patients in the preceding 4 wk was recorded. The diagnosis of H. pylori infection was based on ¹³C-urea breath test at least 4 wk after withdrawal of antisecretory drugs, antibiotics and related drugs. For the patients with subtotal gastrectomy, the diagnosis of H. pylori infection was based on anti-H. pylori immunoglobulin G (IgG) antibody. Serum anti-H. pylori IgG antibody was measured by enzyme-linked immunosorbent assays (Biohit, Finland).

RESULTS: The sensitivity, specificity, positive predictive value and negative predictive value of neutrophil infiltration in the diagnosis of H. pylori infection were 92.3%, 83.5%, 77.4% and 94.7%, respectively. Neutrophil infiltration of gastric mucosa in the histological analysis was strongly associated with H. pylori infection (77.4% vs 5.3% in the neutrophil infiltration negative group, P = 0.000). Moderate neutrophil infiltration was more frequent in H. pylori infection when compared to mild infiltration (81.8% and 75%, respectively), but did not reach statistical significance. For those patients with negative rapid urease test, H. pylori was detected in 73.2% of patients with positive neutrophil infiltration on histology. In patients with subtotal gastrectomy, the diagnostic accuracy of neutrophil infiltration in H. pylori infection was 50%.

CONCLUSION: Neutrophil infiltration is closely associated with H. pylori and may be recognized as a sign of this infection.

Helicobacter pylori: to stain or not to stain?

We performed a retrospective study to investigate the usefulness of immunohistochemical stains for the diagnosis of Helicobacter pylori (HP). We reviewed 200 consecutive gastric biopsy specimens, as well as immunohistochemical stains for HP. Of the biopsy specimens, 32 were positive for HP by immunohistochemical staining; of those, HP was seen on H&E stains in 29 cases (91%). The number of high-power fields required to detect HP on H&E-stained slides ranged from 1 to 25 (mean, 5.75). Combined significant (2+ or 3+) acute and chronic inflammation had a specificity of 98% and a negative predictive value of 97%. Our results show that, in our institution, HP can be seen relatively easily with H&E staining in the majority of cases; however, a small number of cases with significant inflammation can be missed if stains are not used.

1H NMR-based metabonomic applications to decipher gut microbial metabolic influence on mammalian health

Recent advances in molecular biology and microbiology have increased awareness on the importance of the gut microbiota to the overall mammalian host's health status. There is therefore increasing interest in nutrition research to characterise the molecular foundations of the gut microbial mammalian crosstalk at both physiological and biochemical pathway levels. Tackling these challenges can be achieved through systems biology strategies based on the measurement of metabolites to assess the highly complex metabolic exchanges between diverse biological compartments, including organs, biofluids and microbial symbionts. By opening a direct biochemical window into the metabolome, metabonomics is uniquely suited for the identification of biomarkers providing better understanding of these complex metabolic processes. Recent applications of top-down system biology based on (1)H NMR spectroscopy coupled to advanced chemometric modelling approaches provided compelling evidence that system-wide and organ-specific changes in biochemical processes may be finely tuned by gut microbial activities. This review aims at describing current advances in NMR-based metabonomics where the main objective is to discern the molecular pathways and biochemical mechanisms under the influence of the gut microbiota. Furthermore, emphasis is given on nutritional approaches, where the quest for homeostatic balance is dependent not only on the host but also on the nutritional modulation of the gut microbiota-host metabolic interactions, using, for instance, probiotics and prebiotics.

Effect of the period of extrinsic mechanical compression following sclerotherapy in veins in rabbit ears

PURPOSE: Research whether a post-sclerotherapy venous compression period of up to 120 hours is sufficient to avoid reperfusion in treated veins; whether there is a relationship between the inflammatory intensity in venous walls and adjacent tissue and the size of venous thrombosis; whether the intensity of the post-sclerotherapy inflammation varies with the period of compression; whether there is a relationship between the presence of hemosiderin in the tissues adjacent to the sclerosing blood vessels and venous blood clots. METHODS: Twenty eight rabbits, all male, were utilized, distributed into four groups (0, 24, 72 and 120). All the animals were administered with 0.25 ml of 1% polidoconal solution and, as a control, 0.25 ml of 0.9% sodium chloride solution in the marginal dorsal vein of the right and left ears, respectively. Mechanical compression was applied to the perfused stretch of the vein, except for the animals in group 0. The period of compression varied from 0 to 120 hours in the groups. An anatomopathological examination of the section of the right and left marginal dorsal veins of all the animals was conducted. RESULTS: There was no significant difference among the various compression periods, both in terms of the degree of vein thrombosis and in the inflammatory intensity in both ears of the various groups. A positive and significant correlation was observed between the inflammatory intensity and the size of the thrombus and in the occurrence of thrombi and hemosiderin. CONCLUSIONS: A compression period of up to 120 hours is not sufficient to prevent reperfusion in sclerosing blood vessels. The intensity of tissue inflammation is related to the size of the thrombus, but not to the compression period. The presence of hemosiderin in the tissues adjacent to the vessels subjected to sclerosis is related to the presence of venous coagulation.

Progress in genomics, metabolism and biotechnology of bifidobacteria

Members of the genus Bifidobacterium were first described over a century ago and were quickly associated with a healthy intestinal tract due to their numerical dominance in breast-fed babies as compared to bottle-fed infants. Health benefits elicited by bifidobacteria to its host, as supported by clinical trials, have led to their wide application as probiotic components of health-promoting foods, especially in fermented dairy products. However, the relative paucity of genetic tools available for bifidobacteria has impeded development of a comprehensive molecular understanding of this genus. In this review we present a summary of current knowledge on bifidobacterial metabolism, classification, physiology and genetics and outline the currently available methods for genetically accessing and manipulating the genus.

Ureases as a target for the treatment of gastric and urinary infections

Urease is known to be a major contributor to pathologies induced by Helicobacter pylori and Proteus species. In H pylori, urease allows the bacteria to survive in an acidic gastric environment during colonisation, playing an important role in the pathogenesis of gastric and peptic ulcers. Ureolytic activity also results in the production of ammonia in close proximity to the gastric epithelium, causing cell damage and inflammation. In the case of Proteus species (notably Proteus mirabilis) infection, stones are formed due to the presence of ammonia and carbon dioxide released by urease action. In addition, the ammonia released is able to damage the glycosaminoglycan layer, which protects the urothelial surface against bacterial infection. In this context, the administration of urease inhibitors may be an effective therapy for urease-dependent pathogenic bacteria. This is a review of the role of ureases in H pylori and Proteus species infections, focussing on the biochemical and clinical aspects of the most promising and/or potent urease inhibitors for the treatment of gastric and urinary tract infections.

Confocal laser endomicroscopy for diagnosis of Helicobacter pylori infection: a prospective study

BACKGROUND AND AIM

Confocal laser endomicroscopy (CLE) is a new endoscopy technique for subsurface analysis of the gastric mucosa and in vivo histology examination during endoscopy. We aimed to compare the clinical applicability and predictive power of CLE with the diagnosis of Helicobacter pylori infection in patients with gastrointestinal symptoms.

METHODS

A total of 103 consecutive patients scheduled to undergo endoscopy were enrolled. CLE image criteria for H. pylori infection were established in a pilot study of 20 patients, then images for 83 consecutive patients were prospectively evaluated, and data were correlated with the final diagnosis of H. pylori infection in a blinded manner.

RESULTS

We found good association between histopathology and CLE findings. H. pylori infection was identified by CLE with any of the following three features: white spots, neutrophils and microabscesses. The accuracy, sensitivity and specificity of CLE diagnosis of H. pylori infection were 92.8%, 89.2% and 95.7%, respectively. The mean kappa-value for interobserver agreement in the prediction of H. pylori infection was 0.78. Neutrophils were the best diagnostic feature and had good sensitivity (83.8%) and specificity (97.8%). H. pylori-associated changes were more common in the antrum than in the corpus among infected patients (P < 0.001).

CONCLUSIONS

H. pylori infection can be identified by specific cellular and subcellular changes of the surface gastric mucosa with CLE. CLE is a novel, useful method for predicting H. pylori infection in vivo during endoscopy.

A novel compound from celery seed with a bactericidal effect against Helicobacter pylori

Objectives

The aim was to purify and characterise an antimicrobial component from celery (Apium graveolens) seeds, which have been used for centuries as a herbal medicine with reported antibacterial effects.

Methods

A crude alcoholic extract of celery seeds was fractionated by organic solvent extractions, column chromatography and HPLC. Fractions were assayed for antimicrobial activity against the gastric pathogen Helicobacter pylori and other bacteria. The purified antibacterial component was characterised via MS and NMR. Preliminary investigation of its mechanism of action included morphological studies, incorporation of macromolecular precursors, membrane integrity and two-dimensional protein electrophoresis.

Key findings

The purified component, termed ‘compound with anti-Helicobacter activity’ (CAH), had potent bactericidal effects against H. pylori; the minimum inhibitory concentration and minimum bactericidal concentration were 3.15 μg/ml and 6.25–12.5 μg/ml, respectively. CAH (Mr = 384.23; empirical formula C24H32O4) had specific inhibitory effects on H. pylori and was not active against Campylobacter jejuni or Escherichia coli. MS and NMR data were consistent with a dimeric phthalide structure. The results appeared to rule out mechanisms that operated solely by loss of membrane integrity or inhibition of protein or nucleic acid synthesis.

Conclusions

CAH may be suitable for further investigation as a potent agent for treating H. pylori infections.

Partial protection against Helicobacter pylori in the absence of mast cells in mice

The goal of this study is to evaluate the contribution of mast cells to Helicobacter pylori immunity in a model of vaccine-induced protection. Mast cell-deficient Kitl(Sl)/Kitl(Sl-d) and control mice were immunized with H. pylori sonicate plus cholera toxin and challenged with H. pylori, and the bacterial loads, inflammatory infiltrates, and cytokine responses were evaluated and compared at 1, 2, and 4 weeks postchallenge. In vitro stimulation assays were performed using bone marrow-derived mast cells, and recall assays were performed with spleen cells of immunized mast cell-deficient and wild-type mice. Bacterial clearance was observed by 2 weeks postchallenge in mast cell-deficient mice. The bacterial load was reduced by 4.0 log CFU in wild-type mice and by 1.5 log CFU in mast cell-deficient mice. Neutrophil numbers in the gastric mucosa of immune Kitl(Sl)/Kitl(Sl-d) mice were lower than those for immune wild-type mice (P < 0.05). Levels of gastric interleukin-17 (IL-17) and tumor necrosis factor alpha (TNF-alpha) were also significantly lower in immune Kitl(Sl)/Kitl(Sl-d) mice than in wild-type mice (P < 0.001). Immunized mast cell-deficient and wild-type mouse spleen cells produced IFN-gamma and IL-17 in response to H. pylori antigen stimulation. TNF-alpha and CXC chemokines were detected in mast cell supernatants after 24 h of stimulation with H. pylori antigen. The results indicate that mast cells are not essential for but do contribute to vaccine-induced immunity and that mast cells contribute to neutrophil recruitment and inflammation in response to H. pylori.

Monitoring healthy metabolic trajectories with nutritional metabonomics

Metabonomics is a well established analytical approach for the analysis of physiological regulatory processes via the metabolic profiling of biofluids and tissues in living organisms. Its potential is fully exploited in the field of “nutrimetabonomics” that aims at assessing the metabolic effects of active ingredients and foods in individuals. Yet, one of the greatest challenges in nutrition research is to decipher the critical interactions between mammalian organisms and environmental factors, including the gut microbiota. “Nutrimetabonomics” is today foreseen as a powerful approach for future nutritional programs tailored at health maintenance and disease prevention.

Is a 7-day Helicobater pylori treatment enough for eradication and inactivation of gastric inflammatory activity?

AIM: To compare the efficacy of a 7-d vs 10-d triple therapy regarding H pylori eradication, endoscopic findings and histological gastric inflammatory inactivation in the Ecuadorian population.

METHODS: 136 patients with dyspepsia and H pylori infection were randomized in 2 groups (68 per group): group 1, 7-d therapy; group 2, 10-d therapy. Both groups received the same medication and daily dosage: omeprazole 20 mg bid, clarithromycin 500 mg bid and amoxicillin 1 g bid. Endoscopy was performed for histological assessment and H pylori infection status before and 8 wk after treatment.

RESULTS: H pylori was eradicated in 68% of group 1 vs 83.8% of group 2 for the intention-to-treat analysis (ITT) (P = 0.03; OR = 2.48; 95% CI, 1.1-5.8), and 68% in group 1 vs 88% in group 2 for the per-protocol analysis (PP) (P = 0.008; OR = 3.66; 95% CI, 1.4-10). Endoscopic gastric mucosa normalization was observed in 56.9% in group 1 vs 61.2% in group 2 for ITT, with similar results for the PP, the difference being statistically not significant. The rate of inflammatory inactivation was 69% in group 1 vs 88.7% in group 2 for ITT (P = 0.007; OR = 3.00; 95% CI, 1.2-7.5), and 69% in group 1 vs 96% in group 2 for PP (P = 0.0002; OR = 7.25; 95% CI, 2-26).

CONCLUSION: In this Ecuadorian population, the 10-d therapy was more effective than the 7-d therapy for H pylori eradication as well as for gastric mucosa inflammatory inactivation.

Probiotic modulation of symbiotic gut microbial-host metabolic interactions in a humanized microbiome mouse model

The transgenomic metabolic effects of exposure to either Lactobacillus paracasei or Lactobacillus rhamnosus probiotics have been measured and mapped in humanized extended genome mice (germ-free mice colonized with human baby flora). Statistical analysis of the compartmental fluctuations in diverse metabolic compartments, including biofluids, tissue and cecal short-chain fatty acids (SCFAs) in relation to microbial population modulation generated a novel top-down systems biology view of the host response to probiotic intervention. Probiotic exposure exerted microbiome modification and resulted in altered hepatic lipid metabolism coupled with lowered plasma lipoprotein levels and apparent stimulated glycolysis. Probiotic treatments also altered a diverse range of pathways outcomes, including amino-acid metabolism, methylamines and SCFAs. The novel application of hierarchical-principal component analysis allowed visualization of multicompartmental transgenomic metabolic interactions that could also be resolved at the compartment and pathway level. These integrated system investigations demonstrate the potential of metabolic profiling as a top-down systems biology driver for investigating the mechanistic basis of probiotic action and the therapeutic surveillance of the gut microbial activity related to dietary supplementation of probiotics.

Helicobacter pylori infection as a triggering factor of attacks in patients with hereditary angioedema

BACKGROUND

Helicobacter pylori infection is considered among the causative factors of urticaria and angioedema. Having conducted a study on 65 patients, Hungarian authors reported in 2001 that successful eradication of H. pylori is followed by a significant reduction in the number of attacks in patients with hereditary angioedema (HAE). The present study aimed to reinvestigate the relationship between H. pylori infection and the attack rate in the framework of an international collaborative study.

MATERIALS AND METHODS

Within the framework of the PREHAEAT project launched by the European Union, further 152 patients were studied in seven collaborating centers, and participants of the earlier study were followed up in order to detect any relationship between H. pylori infection and the occurrence of attacks in patients suffered from HAE.

RESULTS

The proportion of patients experiencing frequent (> or = 5 per year) abdominal attacks was higher (p = .002) among the H. pylori-infected participants of the international study who underwent eradication as compared to the rest of patients. Successful eradication of H. pylori significantly (p = .0006) reduced the number of attacks in these patients as well. Nine subjects of the previous Hungarian study who underwent eradication therapy for dyspepsia were followed up for an additional 4 years. In these patients, attack frequency remained consistently low.

CONCLUSIONS

As shown by experience from the Hungarian and the international trial, the number of frequent, edematous abdominal attacks may decrease substantially following the eradication of H. pylori from HAE patients infected with this pathogen. Therefore, screening of patients with HAE for H. pylori infection seems warranted. Eradication of H. pylori may lead to a marked reduction in disease severity.

The role of bacterial pathogens in cancer

The association of Helicobacter pylori with gastric cancer is the best-studied relationship between a bacterial infection and cancer. Other bacterial pathogens in humans and rodents are now being recognized as potentially having a direct role in carcinogenesis. Thus, it might be possible to understand the pathogenesis and prevention of certain cancers by studying the bacterial infections associated with them, and their effects on the host. However, the mechanisms by which bacteria contribute to cancer formation are complex, and recent investigations show that they involve the interplay between chronic inflammation, direct microbial effects on host cell physiology and, ultimately, changes in tissue stem cell homeostasis.

Helicobacter pylori persistence: an overview of interactions between H. pylori and host immune defenses

Helicobacter pylori is a gram-negative bacterium that persistently colonizes more than half of the global human population. In order to successfully colonize the human stomach, H. pylori must initially overcome multiple innate host defenses. Remarkably, H. pylori can persistently colonize the stomach for decades or an entire lifetime despite development of an acquired immune response. This review focuses on the immune response to H. pylori and the mechanisms by which H. pylori resists immune clearance. Three main sections of the review are devoted to (i) analysis of the immune response to H. pylori in humans, (ii) analysis of interactions of H. pylori with host immune defenses in animal models, and (iii) interactions of H. pylori with immune cells in vitro. The topics addressed in this review are important for understanding how H. pylori resists immune clearance and also are relevant for understanding the pathogenesis of diseases caused by H. pylori (peptic ulcer disease, gastric adenocarcinoma, and gastric lymphoma).

Urease activity does not reflect the degree of colonization by Helicobacter pylori in children

BACKGROUND

Urea breath test is an accurate method for the diagnosis of Helicobacter pylori infection in children. This test could estimate the bacterial load by measuring the urease activity in gastric mucosa. The aim of the study was to correlate the result of 13C-urea breath test (13C-UBT) and histological estimative for bacterial colonization and severity of inflammatory infiltrate.

METHODS

Forty-four patients (mean age 8.54 +/- 3.9 years) with dyspeptic symptoms were evaluated. Patients were evaluated through endoscopy and 13C-UBT. Helicobacter pylori infection was defined by histology, rapid urease test and 13C-UBT. Breath test results were expressed by delta over baseline (DOB) and urea hydrolysis rate (UHR). Test results were treated logarithmically for statistical analysis.

RESULTS

There was a significant inverse correlation between age and Log DOB (-0.501, P= 0.0005), but there was no relationship between Log UHR and age (-0.148, P= 0.336). The study did not find correlation between the breath test result and histological grades for mononuclear infiltrate, neutrophilic infiltrate and bacterial density.

CONCLUSION

The 13C-UBT does not estimate the severity of histological findings in children with Helicobacter pylori infection. The results of the breath test should be interpreted in a qualitative way.

Eradication of Helicobacter pylori and resolution of gastritis in the gastric mucosa of IL-10-deficient mice

BACKGROUND

Helicobacter pylori has been shown to induce pronounced gastric inflammation in the absence of interleukin-10 (IL-10) by 6 weeks post inoculation. The ability of IL-10(-/-) mice to eradicate H. pylori has not been demonstrated, possibly due to early sacrifice. Therefore, the long-term effect of enhanced gastritis on H. pylori colonization was determined in IL-10(-/-) mice.

METHODS

C57BL/6 and IL-10(-/-) mice were infected with H. pylori and assessed for the degree of gastritis, bacterial load, and in vitro T-cell recall response at 4 and 16 weeks of infection.

RESULTS

Infection of IL-10(-/-) mice resulted in significantly more severe gastritis than wild-type control mice and eradication of H. pylori by 4 weeks post inoculation. By 16 weeks, the level of gastritis in IL-10(-/-) was reduced to the levels observed in wild-type mice. Splenocytes from IL-10(-/-) mice were prone to produce significantly greater amounts of IFN-gamma than wild-type mice when stimulated with bacterial antigens.

CONCLUSIONS

These results indicate that the host is capable of spontaneously eradicating H. pylori from the gastric mucosa when inflammation is elevated beyond the chronic inflammation induced in wild-type mice, and that the gastritis dissipates following bacterial eradication. Additionally, these data provide support for a model of gastrointestinal immunity in which naturally occurring IL-10-producing regulatory T cells modulate the host response to gastrointestinal bacteria.

The relation of Helicobacter pylori to gastric adenocarcinoma and lymphoma: pathophysiology, epidemiology, screening, clinical presentation, treatment, and prevention

Helicobacter pylori infection may be the most common chronic bacterial infection worldwide; however, the prevalence varies between countries and is usually linked to socioeconomic conditions. Gastric cancer is one of the most frequent cancers in developing countries and usually about the seventh most common in developed countries. This article explores the relation of H. pylori to gastric adenocarcinoma and lymphoma. The pathophysiology, epidemiology, screening, clinical presentation, treatment, and prevention are discussed.

Clearance of Helicobacter pylori infection through immunization: the site of T cell activation contributes to vaccine efficacy

Helicobacter pylori vaccine development has progressed rapidly in animal models. Both H. pylori-associated pathogenesis and protective immunity are CD4+ T cell dependent, with no discernable phenotypic difference to distinguish pathogenic T cells from protective T cells. Functionally however, protective T cells promote enhanced inflammation upon H. pylori challenge. Additionally, only mouse models such as phagocyte oxidase- or IL-10-deficient mice that respond to H. pylori infection with intense gastritis are capable of demonstrating spontaneous eradication of the bacteria. These data, combined with recent descriptions of down-regulatory T cells in infected humans and mice, support an emerging model of H. pylori pathogenesis in which H. pylori induces inflammation that is limited by regulatory T cells in the stomach. Immunization therefore may succeed by activating T cells in peripheral lymph nodes that are capable of promoting qualitatively or quantitatively different inflammation when recruited to the stomach. Evidence in support of this model will be discussed.

Comparison of the effects of rebamipide with those of cimetidine on chronic gastritis associated with Helicobacter pylori in Mongolian gerbils

BACKGROUND AND AIMS

The effects of rebamipide on chronic gastritis associated with Helicobacter pylori have not been well-defined. We compared these effects of rebamipide with those of cimetidine in Mongolian gerbils infected with H. pylori.

METHODS

Mongolian gerbils with or without H. pylori were divided into 10 groups 6 weeks after inoculation and fed diets containing a drug (rebamipide or cimetidine) or control diet. All animals were sacrificed 4 weeks after grouping. Their stomachs were examined for histology, colonization by H. pylori, myeloperoxidase activity (myeloperoxidase), production of neutrophil chemokine (CINC/KC) and tumour necrosis factor-alpha (TNF-alpha), and serum gastrin levels.

RESULTS

H. pylori colonized all of the inoculated animals. Neither rebamipide nor cimetidine decreased myeloperoxidase activity, but each reduced wet stomach weight in H. pylori-infected animals. The amount of increase in CINC/KC and TNF-alpha in gastric tissue caused by H. pylori infection was decreased by treatment with rebamipide or cimetidine. H. pylori infection increased serum gastrin levels, and this increase was significantly enhanced by cimetidine but not rebamipide.

CONCLUSIONS

Rebamipide may improve H. pylori-infected chronic gastritis by preventing the production of inflammatory cytokines and chemokines, as does cimetidine, but may be preferable to cimetidine for long-term administration for treatment of H. pylori-infected chronic gastritis due to its effect on serum gastrin levels.

Pathologic features of reflux and Helicobacter pylori-associated carditis: a comparative study

Inflammation of the gastric cardia, which is the most proximal portion of the stomach, in most instances is the result of either gastroesophageal reflux disease or H. pylori infection. Histologic distinction between these two entities is important because the treatment, natural history, and risk of malignancy are different. Moreover, multilayered epithelium, a possible precursor to Barrett's esophagus, has only recently been described in the gastric cardia, and its relationship to gastroesophageal reflux disease is unknown. The aim of this study was to compare the histologic features of the gastric cardia and the prevalence of multilayered epithelium in patients with reflux versus H. pylori-associated carditis. Routinely processed hematoxylin and eosin-stained mucosal biopsies of the gastric cardia from 30 patients with reflux-associated carditis, 25 with H. pylori-associated carditis, and 30 control patients (no reflux, no H. pylori) were evaluated for a wide variety of histologic features such as goblet cell metaplasia, presence of multilayered epithelium, type of glandular epithelium (mucous, oxyntic, mixed mucous/oxyntic), pancreatic metaplasia, overall degree of inflammation, and the quantity of individual types of inflammatory cells. The clinical and histologic features were compared between the two study groups and controls. Clinically, the reflux carditis group (male/female ratio: 21/9, mean age 56 years) had a significantly higher male/female ratio (p <0.01) and a slightly higher mean age in comparison with the H. pylori group (male/female ratio: 9/16, mean age 50 years). Histologically, the reflux group had significantly less overall inflammation (p <0.05), with fewer plasma cells (p <0.04) and neutrophils (p <0.006), but a higher prevalence of multilayered epithelium [9 of 30 (30%) vs 1 of 25 (4%) in the H. pylori group, p = 0.01]. In the reflux carditis group, multilayered epithelium was significantly associated with neutrophilic inflammation (p <0.05), but not any other features of chronic carditis or with any of the specific epithelial cell types. The control group showed less inflammatory activity in comparison with the H. pylori group and a lower prevalence of multilayered epithelium and eosinophilic inflammation in comparison with the reflux group. The clinical and pathologic features of reflux carditis are distinct from H. pylori carditis and are characterized by less overall inflammation and fewer neutrophils and plasma cells. Multilayered epithelium not uncommonly occurs in the cardia of patients with gastroesophageal reflux disease but without Barrett's esophagus, further supporting our hypothesis that multilayered epithelium may represent an early precursor in the development of columnar metaplasia in Barrett's esophagus.