How does Helicobacter pylori cause mucosal damage? Its effect on acid and gastrin physiology

Uncovering the role of traditional Chinese medicine in immune-metabolic balance of gastritis from the perspective of Cold and Hot: Jin Hong Tablets as a case study

Chronic gastritis (CG) is a common inflammatory disease of chronic inflammatory lesion of gastric mucosa and in the diagnosis of gastritis in traditional Chinese medicine (TCM), CG can be classified into Cold ZHENG (syndrome in TCM) and Hot ZHENG. However, the molecular features of Cold/Hot ZHENG in CG and the mechanism of Cold/Hot herbs in formulae for CG remained unclear. In this study, we collected a transcriptomics data including 35 patients of Cold/Hot ZHENG CG and 3 scRNA-seq CG samples. And 25 formulae for CG and 89 herbs recorded in these formulae were also collected. We conduct a comprehensive analysis based on the combination of transcriptomics datasets and machine learning algorithms, to discover biomarkers for Cold/Hot ZHENG CG. Then the target profiles of the collected formulae and Cold/Hot herbs were predicted to uncover the features and biomarkers of them against Cold/Hot ZHENG CG. These biomarkers suggest that Hot ZHENG CG might be characterized by over-inflammation and exuberant metabolism, and Cold ZHENG CG showed a trend of suppression in immune regulation and energy metabolism. Biomarkers and specific pathways of Hot herbs tend to regulate immune responses and energy metabolism, while those of Cold herbs are more likely to participate in anti-inflammatory effects. Finally, the findings were verified based on public transcriptomics datasets, as well as transcriptomics and ELISA detection, taking Jin Hong tablets as a case study. Biomarkers like leptin and IL-6 together with proportions of immune cells showed significant changes after the intervention. These findings might reflect the mechanism and build a bridge between macro and micro views of Cold/Hot ZHENG as well as Cold/Hot herbs.

Risk prediction model for gastric cancer within 5 years in healthy Korean adults

BACKGROUND

Although endoscopy is commonly used for gastric cancer screening in South Korea, predictive models that integrate endoscopy results are scarce. We aimed to develop a 5-year gastric cancer risk prediction model using endoscopy results as a predictor.

METHODS

We developed a predictive model using the cohort data of the Kangbuk Samsung Health Study from 2011 to 2019. Among the 260,407 participants aged ≥20 years who did not have any previous history of cancer, 435 cases of gastric cancer were observed. A Cox proportional hazard regression model was used to evaluate the predictors and calculate the 5-year risk of gastric cancer. Harrell's C-statistics and Nam-D'Agostino χ2 test were used to measure the quality of discrimination and calibration ability, respectively.

RESULTS

We included age, sex, smoking status, alcohol consumption, family history of cancer, and previous results for endoscopy in the risk prediction model. This model showed sufficient discrimination ability [development cohort: C-Statistics: 0.800, 95% confidence interval (CI) 0.770-0.829; validation cohort: C-Statistics: 0.799, 95% CI 0.743-0.856]. It also performed well with effective calibration (development cohort: χ2 = 13.65, P = 0.135; validation cohort: χ2 = 15.57, P = 0.056).

CONCLUSION

Our prediction model, including young adults, showed good discrimination and calibration. Furthermore, this model considered a fixed time interval of 5 years to predict the risk of developing gastric cancer, considering endoscopic results. Thus, it could be clinically useful, especially for adults with endoscopic results.

Morning exercise affects the absorption of oral levothyroxine: a single center pilot study

PURPOSE

Levothyroxine (LT4) is the first-line hormone replacement therapy for hypothyroidism. Several factors which have an influence on oral LT4 absorption have been previously described; however, the influence of exercise on oral LT4 absorption has not been reported, yet. It was aimed to investigate the possible effect of morning exercise, right after LT4 ingestion, on the absorption of LT4 tablets in this study.

PATIENTS AND METHODS

Patients with primary hypothyroidism who fulfilled the inclusion criteria were offered to participate in a 6-week morning exercise programme and those who agreed to participate were enrolled in our study. Patients were required to have a walk for 30 min with a regular speed right after taking their daily LT4 treatments and start having breakfast the first hour after LT4 intake. Pre- and post-exercise TSH levels were recorded and TSH percentage change was calculated.

RESULTS

All patients had decreased TSH levels after the exercise programme. There was a significant decrease in TSH levels (p < 0.001). A significant positive correlation between TSH percentage change and daily dose of LT4 per kg of body weight was also shown.

CONCLUSIONS

This is the first study which demonstrates the significant positive effect of morning exercise on the absorption of LT4 tablets. In addition to that, it was also found that as the daily dose of LT4 increases, the percentage decrease of TSH level becomes greater.

Strategies of Helicobacter pylori in evading host innate and adaptive immunity: insights and prospects for therapeutic targeting

Helicobacter pylori (H. pylori) is the predominant pathogen causing chronic gastric mucosal infections globally. During the period from 2011 to 2022, the global prevalence of H. pylori infection was estimated at 43.1%, while in China, it was slightly higher at approximately 44.2%. Persistent colonization by H. pylori can lead to gastritis, peptic ulcers, and malignancies such as mucosa-associated lymphoid tissue (MALT) lymphomas and gastric adenocarcinomas. Despite eliciting robust immune responses from the host, H. pylori thrives in the gastric mucosa by modulating host immunity, particularly by altering the functions of innate and adaptive immune cells, and dampening inflammatory responses adverse to its survival, posing challenges to clinical management. The interaction between H. pylori and host immune defenses is intricate, involving evasion of host recognition by modifying surface molecules, manipulating macrophage functionality, and modulating T cell responses to evade immune surveillance. This review analyzes the immunopathogenic and immune evasion mechanisms of H. pylori, underscoring the importance of identifying new therapeutic targets and developing effective treatment strategies, and discusses how the development of vaccines against H. pylori offers new hope for eradicating such infections.

Do atrophic gastritis and intestinal metaplasia reverse after Helicobacter pylori eradication?

BACKGROUND

It's still controversial whether Helicobacter pylori (H. pylori) eradication can reverse atrophic gastritis (AG) and intestinal metaplasia (IM). Therefore, we performed a meta-analysis to estimate the effect of H. pylori eradication on AG and IM.

METHODS

We searched the PubMed, Web of Science and EMBASE datasets through April 2023 for epidemiological studies, which provided mean glandular atrophy (GA) or IM score before and after H. pylori eradication, or provided ORs, RRs or HRs and 95% CIs for the association of AG or IM with H. pylori eradication. Weighted mean difference (WMD) and pooled ORs and 95%CIs were used to estimate the effect of H. pylori eradication on AG and IM.

RESULTS

Twenty articles with a total of 5242 participants were included in this meta-analysis. H. pylori eradication significantly decreased GA score in the antrum (WMD -0.36; 95% CI: -0.52, -0.19, p < 0.01), GA score in the corpus (WMD -0.35; 95% CI: -0.52, -0.19, p < 0.01), IM score in the antrum (WMD -0.16; 95% CI: -0.26, -0.07, p < 0.01) and IM score in the corpus (WMD -0.20; 95% CI: -0.37, -0.04, p = 0.01). H. pylori eradication significantly improved AG (pooled OR 2.96; 95% CI: 1.70, 5.14, p < 0.01) and IM (pooled OR 2.41; 95% CI: 1.24, 4.70, p < 0.01). The association remained significant in the subgroup analyses by study design, sites of lesions, regions and follow-up time. Although Publication bias was observed for AG, the association remained significant after trim-and-fill adjustment.

CONCLUSIONS

H. pylori eradication could significantly improve AG and IM at early stage.

Oral nanomedicine biointeractions in the gastrointestinal tract in health and disease

Oral administration is the preferred route of administration based on the convenience for and compliance of the patient. Oral nanomedicines have been developed to overcome the limitations of free drugs and overcome gastrointestinal (GI) barriers, which are heterogeneous across healthy and diseased populations. This review aims to provide a comprehensive overview and comparison of the oral nanomedicine biointeractions in the gastrointestinal tract (GIT) in health and disease (GI and extra-GI diseases) and highlight emerging strategies that exploit these differences for oral nanomedicine-based treatment. We introduce the key GI barriers related to oral delivery and summarize their pathological changes in various diseases. We discuss nanomedicine biointeractions in the GIT in health by describing the general biointeractions based on the type of oral nanomedicine and advanced biointeractions facilitated by advanced strategies applied in this field. We then discuss nanomedicine biointeractions in different diseases and explore how pathological characteristics have been harnessed to advance the development of oral nanomedicine.

Relationship Between Recreational Cannabis Use and Helicobacter pylori Infection

Background: Cannabis plant extracts suppress gastric acid secretion and inflammation, and promote gastroduodenal ulcer healing, all of which are triggered by Helicobacter Pylori infection (HPI). Here, we evaluate the association between cannabis use and HPI among a representative community sample. Materials and Methods: We identified respondents who completed cannabis use questions and were tested for HPI (H. pylori IgG antibody seropositivity) from the National Health and Nutrition Examination Survey III dataset (n=4556). Cannabis usage was categorized as ever-use (ever, never), cumulative lifetime use (>10-times, 1-10-times, never), or recent use (>31-days-ago, within-31-days, never). We calculated the crude and adjusted risk (prevalence rate ratio, cPRR and aPRR) of having HPI with cannabis use using generalized Poisson models (SAS 9.4). The models were adjusted for demographics and risk factors for HPI. Results: The prevalence of HPI was lower among ever versus never cannabis users (18.6% vs. 33%, p<0.0001). Cannabis use was associated with a decreased risk of HPI (cPRR: 0.56 confidence interval [95% CI: 0.47-0.67]; p<0.0001), which persisted after adjusting for demographics (aPRR: 0.75 [95% CI: 0.63-0.90]; p=0.0016) and comorbidities (aPRR: 0.79 [95% CI: 0.66-0.95]; p=0.0145). Further, individuals with >10-times lifetime cannabis use had a decreased risk of HPI compared with those with 1-10-times lifetime use (aPRR: 0.70 [95% CI: 0.55-0.89]; p=0.0011) and never-users (aPRR: 0.65 [95% CI: 0.50-0.84]; p=0.0002). Conclusion: Recreational cannabis use is associated with diminished risk of HPI. These observations suggest the need for additional research assessing the effects of medical cannabis formulations on HPI.

Is There a Relationship Between Helicobacter Pylori and GERD Before Laparoscopic Sleeve Gastrectomy?

AIM

The aim of this study is to determine the prevalence of Helicobacter pylori (HP) in patients before laparoscopic sleeve gastrectomy (LSG) and to reveal whether HP is associated with gastroesophageal reflux disease (GERD) before LSG.

METHODS

The study included 435 patients who underwent primary LSG between April 2018 and September 2021. All patients underwent preoperative endoscopy. All patients were investigated for the presence of HP. No treatment for HP eradication was given to any of the patients. Patients were divided into 2 groups HP (+) and HP(-), and compared for GERD, complications, and weight loss before and after LSG.

RESULTS

The mean age of the patients was 38.3±11 years (56.1% female), and the mean BMI was 44.2±7.1 kg/m 2 . Symptomatic GERD was found in 102 (23.4%) patients. Endoscopy showed hiatal hernia in 42 (9.7%) patients, and these patients also underwent hiatal hernia repair in the same session. HP was (+) in 125 (28.7%) patients. HP (+) patients were assigned to Group A, while HP (-) patients were assigned to Group B. In the preoperative period, the rate of symptomatic GERD was 22.4% (n=28/125) in Group A and 23.9% (n=74/310) in Group B ( P =0.74). The mean follow-up period was 17±5.7 (range, 12 to 28) months. The mean BMI decreased to 28.3±4.9 kg/m 2 at 12 months after LSG. Given the association between HP and GERD after LSG, it was 25.6% (n=32/125) in Group A and 20% (n=62/310) in Group B ( P =0.2). In addition, there was no difference between the 2 groups in terms of weight loss.

CONCLUSION

This study showed no difference between patients with or without HP infection in terms of GERD before LSG.

Chronic Stress-Related Gastroenteric Pathology in Cheetah: Relation between Intrinsic and Extrinsic Factors

Simple Summary

The cheetah is the fastest land mammal. Habitat destruction, high mortality due to other predators, and illegal wildlife trade has led to a decrease in the wild population. Currently, the global adult population present in their natural habitat is estimated to be 7100 individuals. In captivity, the population suffers from limited reproduction and disease. Both the wild and captive populations have reduced genetic diversity from a historic bottleneck, leading to increased ecological and environmental vulnerability. Over the years, conservation programs have been developed for habitat protection, management of human–animal conflict, and the study of disease and genetics. Among these, the one with the greatest prevalence in captivity is chronic gastritis. This review analyzes the scientific literature on gastric pathology in cheetah, with the potential causes divided into “extrinsic factors”, such as living conditions and diet, and “intrinsic factors”, including the presence of Helicobacter-like organisms and the genetic predisposition.

Abstract

The rapid decline of cheetah (Acinonyx jubatus) throughout their range and long-term studies of captive breeding has increased conservation action for this species including the study of chronic diseases. Gastritis is one of the captive diseases that leads to high mortality presented with symptoms including vomiting, diarrhea, anorexia, and weight loss. The disease presents different histological lesions in the gastrointestinal tract that are characterized by inconstant and different clinical appearance in captive and free-range cheetahs. The aim of this review is to summarize the causes of chronic gastritis in the cheetah. Factors including diet, living conditions, infections with gastric Helicobacter-like organisms (GHLOs), the lack of genetic polymorphism and the cheetah’s specific-immunocompetence are analyzed. All studies on gastroenteric cheetah pathologies, conducted between 1991 (to the best of our knowledge, the first report on online databases) and 2021, are included in this review, highlighting the possible correlation between stress-related captive conditions and chronic gastric pathology.

Helicobacter pylori infection and iron deficiency in non-elderly adults participating in a health check-up program

BACKGROUND/AIMS

Helicobacter pylori infection is presumably associated with iron deficiency and iron deficiency anemia (IDA). This study aimed to evaluate the relationship between H. pylori infection and the decline in iron stores in non-elderly adults during their health check-ups.

METHODS

We identified a total of 1,069 subjects who were tested for iron, ferritin, and total iron-binding capacity during their health check-ups, from January 2016 to May 2017. Of these, subjects who underwent endoscopy via rapid urease test and those aged 65 years or below were finally enrolled.

RESULTS

Overall, 281 subjects were enrolled, and 187 patients (66.5%) tested positive for H. pylori. The mean age was 36.1 years (range, 22 to 65), and 176 subjects (62.6%) were male. The mean levels of hemoglobin (14.1 ± 1.7 g/dL vs. 14.6 ± 1.4 g/dL, p = 0.019) and ferritin (121.7 ± 106.9 ng/mL vs. 151.8 ± 107.8 ng/mL, p = 0.027) in the H. pylori-positive group were significantly lower than those in the H. pylori-negative group. Iron deficiency (ferritin < 30 ng/mL) was more common in patients with H. pylori infection (p = 0.002). There was no significant difference in anemia (hemoglobin < 13 g/dL in men, < 12 g/dL in women) or IDA (anemia, ferritin < 10 ng/mL, and transferrin saturation < 16%) with H. pylori. Logistic regression analysis demonstrated that female sex (odds ratio, 197.559; 95% confidence interval, 26.461 to 1,475.015) and H. pylori infection (odds ratio, 3.033; 95% confidence interval, 1.216 to 7.567) were factors associated with iron deficiency.

CONCLUSION

H. pylori infection is associated with iron deficiency, suggesting a decline in iron stores among infected non-elderly adults.

A double helix-shaped optical fiber sensor for non-endoscopic diagnosis of gastrin-17

Non-endoscopic tools for the diagnostic evaluation of patients should be promoted in the field of biomedical assay and the need for highly sensitive, efficient, low-cost, and user-friendly sensors must be considered.

Evidence based guidelines for the treatment of Helicobacter pylori infection in Korea 2020

Helicobacter pylori infection is one of the most common infectious diseases worldwide. H. pylori is responsible for substantial gastrointestinal morbidity with a high disease burden. Since the revision of the H. pylori Clinical Practice Guidelines in 2013 in Korea, the eradication rate of H. pylori has gradually decreased with the use of a clarithromycin based triple therapy. According to a nationwide randomized controlled study by the Korean College of Helicobacter and Upper Gastrointestinal Research released in 2018, the intention-to-treat eradication rate was only 63.9%, which was mostly due to increased antimicrobial resistance to clarithromycin. The clinical practice guidelines for treatment of H. pylori were updated based on evidence-based medicine from a meta-analysis conducted on a target group receiving the latest level of eradication therapy. The draft recommendations developed based on the meta-analysis were finalized after expert consensus on three recommendations regarding the indication for treatment and eight recommendations on the treatment itself. These guidelines were designed to provide clinical evidence for the treatment of H. pylori to patients, nurses, medical school students, policymakers, and clinicians. These may differ from current medical insurance standards, and will be revised if more evidence emerges in the future.

Helicobacter pylori, Sleeve Gastrectomy, and Gastroesophageal Reflux Disease; Is there a Relation?

PURPOSE

Sleeve gastrectomy (SG) is an effective bariatric procedure, yet can be associated with complications as gastroesophageal reflux disease (GERD). The present study aimed to investigate the prevalence of Helicobacter pylori (H. pylori) in SG specimens, its relation with GERD, and its impact on postoperative outcomes.

METHODS

All SG specimens received in the pathology laboratory were reviewed. The prevalence of H. pylori in SG specimens was recorded. Patients with H. pylori infection who received triple therapy were compared with patients without H pylori in terms of baseline characteristics, preoperative GERD and its outcome postoperatively, development of new-onset GERD, staple line complications, and weight loss.

RESULTS

The records of 176 patients were reviewed; 69 (39.2%) were positively tested on H. pylori infection. Patients with H. pylori had higher body mass index (BMI) (RR = 1.51), greater incidence of preoperative GERD (RR = 1.67), and complained more of dyspepsia (RR = 1.87). Eradication of H. pylori was achieved in 67 (97.1%) of 69 patients. Postoperative improvement in GERD symptoms (44.4% Vs 19%, p = 0.036) and dyspepsia (85.7% Vs 51.7%, p = 0.007) was higher in patients with H. pylori with confirmed eradication of infection than patients without H. pylori. Both groups had similar operation time, postoperative BMI, excess weight loss, staple line complications, and new-onset GERD.

CONCLUSIONS

More than one-third of patients with morbid obesity had H. pylori infection. Morbidly obese patients with H. pylori infection may be more prone to develop GERD symptoms; yet after eradication of the infection, they may also experience better improvement in symptoms after SG.

Evidence-Based Guidelines for the Treatment of Helicobacter pylori Infection in Korea 2020

Helicobacter pylori infection is one of the most common infectious diseases worldwide. Although the prevalence of H. pylori is gradually decreasing, approximately half of the world&#039;s population still becomes infected with this disease. H. pylori is responsible for substantial gastrointestinal morbidity worldwide, with a high disease burden. It is the most common cause of gastric and duodenal ulcers and gastric cancer. Since the revision of the H. pylori clinical practice guidelines in 2013 in Korea, the eradication rate of H. pylori has gradually decreased with the use of a clarithromycin-based triple therapy for 7 days. According to a nationwide randomized controlled study conducted by the Korean College of Helicobacter and Upper Gastrointestinal Research released in 2018, the intention-to-treat eradication rate was only 63.9%, which was mostly due to increased antimicrobial resistance, especially from clarithromycin. The clinical practice guidelines for the treatment of H. pylori were updated according to evidence-based medicine from a meta-analysis conducted on a target group receiving the latest level of eradication therapy. The draft recommendations developed based on the meta-analysis were finalized after an expert consensus on three recommendations regarding the indication for treatment and eight recommendations for the treatment itself. These guidelines were designed to provide clinical evidence for the treatment (including primary care treatment) of H. pylori infection to patients, nurses, medical school students, policymakers, and clinicians. These may differ from current medical insurance standards and will be revised if more evidence emerges in the future.

Evidence-based Guidelines for the Treatment of Helicobacter pylori Infection in Korea: 2020 Revised Edition

Helicobacter pylori (H. pylori) infection is one of the most common infectious diseases worldwide. Although its incidence is gradually decreasing, about half of the world's population still get infected. H. pylori infection is responsible for substantial gastrointestinal morbidity worldwide. It is the most common cause of gastric and duodenal ulcers as well as gastric cancer. Since the revision of the H. pylori Clinical Practice Guidelines in 2013, the eradication rate of H. pylori has gradually decreased with the use of classical triple therapy, wherein amoxicillin, clarithromycin, and proton pump inhibitors are administered, for 7 days. According to a nationwide randomized controlled study conducted by the Korean College of Helicobacter and Upper Gastrointestinal Research released in 2018, the intention-to-treat eradication rate was only 63.9%, which was due to increased antimicrobial resistance induced by the use of antibiotics, especially clarithromycin. The update of clinical practice guideline for treatment of H. pylori was developed based on evidence-based medicine by conducting a meta-analysis. The draft recommendations were finalized after expert consensus on three recommendations regarding the indication for treatment and eight recommendations on the treatment itself. These guidelines are designed to provide patients, nurses, medical school students, policymakers, and clinicians with clinical evidence to guide primary care and treatment of H. pylori infection. These may differ from current medical insurance standards and will be revised further, if necessary, based on research-based evidence.

Helicobacter pylori, Sleeve Gastrectomy, and Gastroesophageal Reflux Disease; Is there a Relation?

PURPOSE

Sleeve gastrectomy (SG) is an effective bariatric procedure, yet can be associated with complications as gastroesophageal reflux disease (GERD). The present study aimed to investigate the prevalence of Helicobacter pylori (H. pylori) in SG specimens, its relation with GERD, and its impact on postoperative outcomes.

METHODS

All SG specimens received in the pathology laboratory were reviewed. The prevalence of H. pylori in SG specimens was recorded. Patients with H. pylori infection who received triple therapy were compared with patients without H pylori in terms of baseline characteristics, preoperative GERD and its outcome postoperatively, development of new-onset GERD, staple line complications, and weight loss.

RESULTS

The records of 176 patients were reviewed; 69 (39.2%) were positively tested on H. pylori infection. Patients with H. pylori had higher body mass index (BMI) (RR = 1.51), greater incidence of preoperative GERD (RR = 1.67), and complained more of dyspepsia (RR = 1.87). Eradication of H. pylori was achieved in 67 (97.1%) of 69 patients. Postoperative improvement in GERD symptoms (44.4% Vs 19%, p = 0.036) and dyspepsia (85.7% Vs 51.7%, p = 0.007) was higher in patients with H. pylori with confirmed eradication of infection than patients without H. pylori. Both groups had similar operation time, postoperative BMI, excess weight loss, staple line complications, and new-onset GERD.

CONCLUSIONS

More than one-third of patients with morbid obesity had H. pylori infection. Morbidly obese patients with H. pylori infection may be more prone to develop GERD symptoms; yet after eradication of the infection, they may also experience better improvement in symptoms after SG.

Clostridium difficile-associated disease and Helicobacter pylori seroprevalence: A case-control study

BACKGROUND

Helicobacter pylori inhabits the stomach and causes persistent inflammation, with changes in gastric acidity. However, it is unclear whether the presence of H pylori plays a role in Clostridium difficile-associated disease (CDAD). The study's aim was to examine relationships of H pylori seroprevalence and serum pepsinogens (PGs), as markers of gastric inflammation, with CDAD.

MATERIALS AND METHODS

A case-control study was conducted among 49 CDAD cases and 54 controls (median age 82 years). Using enzyme-linked immunosorbent assays, sera were tested for H pylori IgG antibody, and PGI and PGII levels. Helicobacter pylori-positive samples were tested for IgG antibody to recombinant cytotoxin-associated gene A (CagA) virulent protein. Logistic regression models were fitted.

RESULTS

Cases and controls were comparable in age (P = .5) and sex distribution (females 62% vs 57%, P = .6). Helicobacter pylori IgG seroprevalence was 47%, of whom 23% were CagA seropositives. Among cases compared to controls, 43% vs 28% were H pylori seropositive but lacking CagA IgG antibody: adjusted odd ratio (OR) 3.43 (95% confidence intervals [CI] 1.29-9.10); 18% vs 4% were positive for CagA phenotype: adjusted OR 9.32 (95% CI 1.61-53.76). This association was not affected by PG levels.

CONCLUSIONS

Helicobacter pylori infection, especially with CagA virulent phenotype, might predispose to C difficile infection in elderly patients.

Asymptomatic Helicobacter Pylori Infection in Preschool Children and Young Women Does Not Predict Iron Bioavailability from Iron-Fortified Foods

Helicobacter pylori infection is common in low-income countries. It has been associated with iron deficiency and reduced efficacy of iron supplementation. Whether H. pylori infection affects iron absorption from fortified and biofortified foods is unclear. Our objective was to assess whether asymptomatic H. pylori infection predicts dietary iron bioavailability in women and children, two main target groups of iron fortification programs. We did a pooled analysis of studies in women of reproductive age and preschool children that were conducted in Benin, Senegal and Haiti using stable iron isotope tracers to measure erythrocyte iron incorporation. We used mixed models to assess whether asymptomatic H. pylori infection predicted fractional iron absorption from ferrous sulfate, ferrous fumarate or NaFeEDTA, controlling for age, hemoglobin, iron status (serum ferritin), inflammation (C-reactive protein), and test meal. The analysis included 213 iron bioavailability measurements from 80 women and 235 measurements from 90 children; 51.3% of women and 54.4% of children were seropositive for H. pylori. In both women and children, hemoglobin (Hb), serum ferritin (SF), and C-reactive protein (CRP) did not differ between the seropositive and seronegative groups. Geometric mean (95% CI) fractional iron absorption (%), adjusted for SF, was 8.97% (7.64, 10.54) and 6.06% (4.80, 7.67) in H. pylori positive and negative women (p = 0.274), and 9.02% (7.68, 10.59) and 7.44% (6.01, 9.20) in H. pylori positive and negative children (p = 0.479). Our data suggest asymptomatic H. pylori infection does not predict fractional iron absorption from iron fortificants given to preschool children or young women in low-income settings.

Modification of the Gastric Mucosal Microbiota by a Strain-Specific Helicobacter pylori Oncoprotein and Carcinogenic Histologic Phenotype

Microbial communities are essential for the maintenance of human health, and when these communities are altered, hosts can become susceptible to inflammation and disease. Dysbiosis contributes to gastrointestinal cancers, and specific bacterial species are associated with this phenotype. This study uses a robust and reproducible animal model to demonstrate that H. pylori infection induces gastric dysbiosis in a cagA-dependent manner and further that dysbiosis and altered microbial community structure parallel the severity of H. pylori-induced gastric injury. Ultimately, such models of H. pylori infection and cancer that can effectively evaluate multiple determinants simultaneously may yield effective strategies for manipulating the gastric microbiota to prevent the development of gastric cancer.

Helicobacter pylori is the strongest risk factor for gastric adenocarcinoma; however, most infected individuals never develop this malignancy. Strain-specific microbial factors, such as the oncoprotein CagA, as well as environmental conditions, such as iron deficiency, augment cancer risk. Importantly, dysbiosis of the gastric microbiota is also associated with gastric cancer. To investigate the combinatorial effects of these determinants in an in vivo model of gastric cancer, Mongolian gerbils were infected with the carcinogenic cag⁺H. pylori strain 7.13 or a 7.13 cagA isogenic mutant, and microbial DNA extracted from gastric tissue was analyzed by 16S rRNA sequencing. Infection with H. pylori significantly increased gastric inflammation and injury, decreased α-diversity, and altered microbial community structure in a cagA-dependent manner. The effect of iron deficiency on gastric microbial communities was also investigated within the context of infection. H. pylori-induced injury was augmented under conditions of iron deficiency, but despite differences in gastric pathology, there were no significant differences in α- or β-diversity, phyla, or operational taxonomic unit (OTU) abundance among infected gerbils maintained on iron-replete or iron-depleted diets. However, when microbial composition was stratified based solely on the severity of histologic injury, significant differences in α- and β-diversity were present among gerbils harboring premalignant or malignant lesions compared to gerbils with gastritis alone. This study demonstrates that H. pylori decreases gastric microbial diversity and community structure in a cagA-dependent manner and that as carcinogenesis progresses, there are corresponding alterations in community structure that parallel the severity of disease.

The Difference of Serum Gastrin-17 Level Based on Gastritis Severity and Helicobacter Pylori Infection

BACKGROUND

Gastritis was defined as the histological presence of gastric mucosal inflammation. One of the most common aetiology was H. pylori. Gastrin-17 was a hormone that was secreted by G cells. H. pylori infection induced increased in gastrin-17 in gastritis. Therefore, this study was to investigate the relationship of gastrin-17 with gastritis severity and H. pylori infection.

AIM

To determine the difference in serum Gastrin-17 level based on gastritis severity and H. pylori infection.

METHODS

A cross-sectional study enrolling 45 patients with gastritis was conducted in Haji Adam Malik General Hospital between April and July 2018. Endoscopy and biopsy examinations were performed to confirm the diagnosis of gastritis. Gastritis severity was assessed using the Updated Sydney System. The presence of H. pylori infection was detected by a Campylobacter-like organism (CLO) examination. Gastrin-17 level and demographic data were also gathered. The analysis was done using Mann Whitney and Kruskal-Wallis test. P-value of < 0.05 was considered statistically significant.

RESULTS

Serum Gastrin-17 level was significantly different based on gastritis severity (P = 0.001 according to neutrophils infiltration and P = 0.023 according to degree of atrophy), H. pylori infection (P = 0.038), and combined gastritis severity and H. pylori infection (P < 0.001). Serum Gastrin-17 level was higher in subjects with severe neutrophils infiltration, without atrophy, and with H. pylori infection.

CONCLUSION

There was a significant difference in serum Gastrin-17 level based on gastritis severity and H. pylori infection.

An updated systematic review and meta-analysis on the association between Helicobacter pylori infection and iron deficiency anemia

BACKGROUND

We conducted an updated systematic review and meta-analysis to examine the prevalence of depleted iron stores among persons infected with Helicobacter pylori compared to uninfected ones. We also assessed the impact of anti-H. pylori eradication therapy plus iron therapy on ferritin and hemoglobin levels compared to iron therapy alone.

METHODS

A literature search was conducted using the databases Medline, the Cochrane Library, Cochrane Central Register of Controlled Trials, EMBASE, and the Science Citation Index Expanded. Observational studies with methodological quality score of 13 (median score) and above, on a scale of 0-16, and all randomized controlled trials (RCTs) were eligible for the meta-analyses. Pooled point estimates and 95% confidence intervals (CI) were obtained using the random effects model.

RESULTS

Compared to uninfected persons, H. pylori-infected individuals showed increased likelihood of iron deficiency anemia (14 observational studies); pooled OR 1.72 (95% CI 1.23-2.42); iron deficiency (pooled OR 1.33; 95% CI 1.15-1.54; 30 studies); and anemia (pooled OR 1.15; 95% CI 1.00-1.32; 23 studies). Meta-analyses of seven RCTs showed increased ferritin, standardized mean difference (SMD) 0.53 (95% 0.21-0.85), but not hemoglobin, SMD 0.36 (95% -0.07 to 0.78), Pv=.1, following anti-H. pylori eradication therapy plus iron therapy as compared with iron therapy alone. Significant heterogeneity was found among studies, as well as evidence of publication bias.

CONCLUSIONS

Current evidence indicates increased likelihood of depleted iron stores in relation to H. pylori infection. H. pylori eradication therapy, added to iron therapy, might be beneficial in increasing ferritin and hemoglobin levels.

Clinical features and management of type I gastric carcinoids

Type I gastric carcinoids (TIGCs) are related to chronic atrophic gastritis and are characterized by hypergastrinemia and hyperplasia of enterochromaffin-like cells. TIGCs are the most frequently diagnosed of all gastric carcinoids, accounting for about 70-80 %. Endoscopically, TIGCs are present as small (<10 mm), polypoid lesions or, more frequently, as smooth, rounded submucosal lesions. Histologically, TIGCs arise in the deep mucosa, with some invading the submucosa. Most TIGCs are well-differentiated tumors, with metastasis being rare. Therefore, patients with TIGCs generally have an excellent prognosis. Among the currently available treatment options are total gastrectomy, partial resection, antrectomy, endoscopic resection, and endoscopic surveillance, although no consensus has been reached on their optimal management. Further studies are needed to develop better management options for patients with TIGC.

Age-dependent association among Helicobacter pylori infection, serum pepsinogen levels and immune response of children to live oral cholera vaccine CVD 103-HgR

Background

Through its effects on gastric secretion, we hypothesized that Helicobacter pylori infection may influence oral immunization. Accordingly, we examined the association between H. pylori infection, serum pepsinogen (PG) (measures for H. pylori gastritis) and vibriocidal antibody (a correlate of protection) seroconversion following oral immunization with CVD 103-HgR live cholera vaccine among children of different ages.

Methods

Sera from 422 Chilean children who were vaccinated with a single dose of CVD 103-HgR were tested by ELISA for serum IgG antibodies to H. pylori, PG I and PG II levels and antibodies to Shigella flexneri 2a lipopolysaccharide and hepatitis A virus (as markers of low socioeconomic status and exposure to enteric pathogens).

Results

The likelihood of vibriocidal antibody seroconversion following vaccination with CVD 103-HgR was significantly decreased in H. pylori-seropositive children age 6 months to 4 years with PG II>8 µg/L (adjusted OR 0.14 (95% CI 0.03–0.61; P = 0.009), and also in H. pylori seropositives with lower PG II level (adjusted OR 0.34, 95% CI 0.14–0.83; P = 0.017), compared to H. pylori-seronegatives. H. pylori-seropositive children aged 5–9 years with serum PG I>30 µg/L (indicating more severe gastritis) had higher odds of vibriocidal seroconversion than those with lower PG I levels (adjusted OR 4.41, 95%CI 1.26–15.38; P = 0.02). There was no significant association between exposures to S. flexneri 2a or hepatitis A virus and vibriocidal seroconversion.

Conclusions

As H. pylori gastritis progresses with increasing pediatric age in developing country venues, changes in gastric secretion ensue that we believe explain the observed differences in age-related immune responses to immunization with live oral cholera vaccine. The effect of H. pylori and changes of gastric acid secretion on the immunogenicity of various oral vaccines should be studied in different developing, transitional and industrialized country settings.

The prevalence of helicobacter pylori infection in patients with reflux esophagitis - our experience

Introduction and aim:

The role of Helicobacter pylori in esophageal disease has not been clearly defined. To clarify this issue, we analyzed 120 patients with histologically confirmed esophageal disease.

Material and methods:

In this prospective study, 120 patients who underwent upper endoscopy examination were included; among them 70 patients with clinically, endoscopically and histologically confirmed GERD, and 50 patients with BE. This investigation was performed in the Clinic of Gastrohepatology in Prishtina, during the period: June 2009–December 2011. Each patient was investigated for H. pylori infection, by performing biopsy for HUT test.

Results:

In BE group, H. pylori infection was present in 16.0% of patients. In GERD group, H. pylori infection was present in 42.9%, and in patients of the control group, in 52.0% of cases. So, in BE group, the prevalence of H. pylori infection showed less significant difference, compared to the control group (P = 0.003) and in GERD group (P = 0.0035). Between GERD group and the control group there was no significant difference (GERD vs. G control. P = 0.421).

Conclusion:

The prevalence of H. pylori infection in patients with BE (16%) was lower in comparison with patients with GERD (42.9%) and with control group (p <0.01). The prevalence of H. pylori infection in patients with BE, especially those with LSBE (9.1%) was very low, which indicates a possible protective role of this microorganism.

Helicobacter pylori infection affects immune responses following vaccination of typhoid-naive U.S. adults with attenuated Salmonella typhi oral vaccine CVD 908-htrA

BACKGROUND

 We examined the association between Helicobacter pylori infection and the immune response following oral immunization of US adults with attenuated Salmonella Typhi vaccine CVD 908-htrA.

METHODS

 Baseline sera from 74 volunteers without a history of typhoid fever who were immunized orally with CVD 908-htrA were tested by enzyme-linked immunosorbent assay for immunoglobin G (IgG) antibodies to H. pylori, hepatitis A antibodies (a marker of low socioeconomic status and exposure to enteric infections), and pepsinogen (PG) I and II levels (measures of gastric inflammation). IgG against S. Typhi lipopolysaccharide (LPS) O and flagella was measured before and 28 days following immunization; a ≥4-fold increase in titer from baseline constituted seroconversion.

RESULTS

 Seroconversion of S. Typhi IgG LPS antibodies was significantly higher among vaccinees infected with H. pylori versus uninfected subjects: adjusted odds ratio (OR) 3.8, 95% confidence interval (CI), 1.1-12.6 (P = .03). A low PG I:PG II ratio (<5), indicating more advanced corpus gastritis, increased the odds of seroconversion of IgG S. Typhi flagella antibody (adjusted OR 6.4, 95% CI, 1.3-31.4; P = .02). Hepatitis A infection did not influence the immune response to CVD 908-htrA.

CONCLUSIONS

 H. pylori infection and gastric inflammation may enhance humoral immunity to oral attenuated S. Typhi vaccine.

Helicobacter pylori infection in functional dyspepsia

Functional dyspepsia is the most common reason for patients to experience chronic epigastric pain or discomfort. The causes of functional dyspepsia are multifactorial but Helicobacter pylori infection is one likely candidate. Infection with this bacterial pathogen clearly results in chronic mucosal inflammation in the stomach and duodenum, which, in turn, might lead to abnormalities in gastroduodenal motility and sensitivity. Chronic gastritis might also affect a variety of endocrine functions of the stomach including the production of the gastrointestinal hormones and neurotransmitters somatostatin, gastrin and ghrelin. Although these abnormalities might generate symptoms in some patients with functional dyspepsia, the clinical evidence needs to be critically evaluated before this hypothesis can be confirmed. A Cochrane review reported that eradication of H. pylori in these patients had a small but statistically significant long-term effect on symptom relief when compared with placebo, lasting at least 12 months after 1 week of eradication therapy. The efficacy of eradication therapy was seen in all symptom subtypes of functional dyspepsia, but was more marked in Asian than Western patients. This evidence has led to alterations in most of the major guidelines throughout the world, which now recommend H. pylori eradication in patients with functional dyspepsia if they test positive for this bacterium.

Helicobacter pylori induction of the gastrin promoter through GC-rich DNA elements

BACKGROUND

Helicobacter pylori (H. pylori) infection has been linked to the development of chronic gastritis, duodenal ulcer disease, and gastric cancer. Helicobacter pylori- infected patients and animal models develop hypergastrinemia, chronic gastritis, and gastric atrophy. Since gastrin is an important regulator of gastric acid secretion and cell growth, H. pylori regulation of this hormone has been implicated in its pathogenesis.

OBJECTIVES

To investigate the effect of H. pylori on gastrin gene expression in mice and of human bacterial isolates on gastrin mRNA expressed in a human cell line.

METHODS

Gastrin mRNA was measured by qRT-PCR in H. pylori-infected mice. H. pylori were co-cultured with AGS cells to study regulation of human gastrin gene expression. Various MAP kinases were implicated in signal transduction from the bacteria using specific inhibitors. Gastrin reporter constructs and gel shift assays were used to map DNA responsive elements.

RESULTS

In addition to an increase in gastrin mRNA in H. pylori-infected mice, H. pylori induced the endogenous human gastrin gene through MAP kinase-dependent signaling but not NFκB-dependent signaling. Activation of gastrin through MAPK signaling did not require CagA or VacA virulence factors. Transfection studies demonstrated that a GC-rich motif mediated H. pylori-induction of the gastrin promoter and that the motif inducibly binds Sp1 and Sp3 transcription factors.

CONCLUSIONS

Direct contact of live H. pylori bacteria with human cells is sufficient to induce gastrin gene expression.

The role of serum pepsinogen and gastrin test for the detection of gastric cancer in Korea

BACKGROUND AND AIM

This study was performed to determine whether serum pepsinogen (PG) and gastrin testing can be used to detect gastric cancer in Korea.

METHODS

Serum levels of PG I (sPGI) and sPGII, PG I/II ratios, and gastrin levels were measured in 1006 patients with gastroduodenal diseases including cancer. Follow-up tests were performed 1 year after Helicobacter pylori eradication.

RESULTS

sPGI and sPGII levels increased and PG I/II ratios decreased in line with the severity of activity, chronic inflammation, and the presence of H. pylori (p < .01). In contrast, sPGI levels and PG I/II ratios decreased in proportion with the severity of atrophic gastritis (AG)/intestinal metaplasia (p < .01). Gastrin levels were found to be correlated with chronic inflammation negatively in the antrum but positively in the corpus. H. pylori eradication reduced sPGI, sPGII, and gastrin levels, and increased PG I/II ratios to the levels of H. pylori-negative patients, and was found to be correlated with reductions in activity and chronic inflammation of gastritis. The sensitivity and specificity of a PG I/II ratio of < or = 3.0 for the detection of dysplasia or cancer were 55.8-62.3% and 61%, respectively. In addition, sPGI and sPGII levels of intestinal-type cancer were significantly lower than those of the diffuse type, respectively (p = .008 and p = .05, respectively). Gastric cancer risk was highest in the H. pylori-positive, low PGI/II ratio (< or = 3.0) group with an odds ratio of 5.52 (confidence interval: 2.83-10.77).

CONCLUSION

PG I/II ratio (< or = 3.0) was found to be a reliable marker for the detection of dysplasia or gastric cancer, especially of the intestinal type. This detection power of PG I/II ratio (< or = 3.0) significantly increased in the presence of H. pylori, and thus, provides a means of selecting those at high risk of developing gastric cancer in Korea.

Molecular mechanisms in therapy of acid-related diseases

Inhibition of gastric acid secretion is the mainstay of the treatment of gastroesophageal reflux disease and peptic ulceration; therapies to inhibit acid are among the best-selling drugs worldwide. Highly effective agents targeting the histamine H2 receptor were first identified in the 1970s. These were followed by the development of irreversible inhibitors of the parietal cell hydrogen-potassium ATPase (the proton pump inhibitors) that inhibit acid secretion much more effectively. Reviewed here are the chemistry, biological targets and pharmacology of these drugs, with reference to their current and evolving clinical utilities. Future directions in the development of acid inhibitory drugs include modifications of current agents and the emergence of a novel class of agents, the acid pump antagonists.

Does Helicobacter pylori infection per se cause gastric cancer or duodenal ulcer? Inadequate evidence in Mongolian gerbils and inbred mice

A role for Helicobacter pylori infection in the development of gastric cancer in humans is well established; however, evidence for its carcinogenicity in animals remains inadequate. Mongolian gerbils and mice are commonly used to investigate the carcinogenicity of H. pylori, yet it is unclear whether H. pylori infection per se causes gastric cancer or duodenal ulcers in these animal models. Gastric adenocarcinoma in the gerbils was reported over 10 years ago, but this species has proved an unreliable model for studying H. pylori infection-associated gastric cancer. Helicobacter pylori infection alone appears insufficient to induce gastric cancer in these animals; additional carcinogenic insult is required. The development of invasive adenocarcinoma in inbred mice is rare regardless of the mouse or bacterial strain, and many long-term studies have failed to induce gastric cancer in these animals. Helicobacter pylori infection is also an established causative factor for duodenal ulcer in humans. However, few studies have attempted to develop animal models of H. pylori infection-induced duodenal ulcer. We therefore conclude that both Mongolian gerbils and inbred mice may be inadequate models for studying H. pylori infection-associated gastric cancer and that there is no animal model of H. pylori infection-induced duodenal ulcer.

Helicobacter pylori infection and related gastrointestinal diseases

Helicobacter pylori has been implicated in the pathogenesis of a number of digestive tract disorders, such as chronic active gastritis, peptic ulceration, gastric cancer, and mucosa-associated lymphoid tissue lymphoma. Disease outcome is dependent on many factors, including bacterial genotype, host physiology and genetics, and environmental factors such as diet. Researchers continue to explore the complexities of H. pylori infection, seeking to explain why some individuals have asymptomatic infection, whereas others experience clinical disease. The importance of treating H. pylori infection in patients with gastrointestinal problems has been confirmed in recent years, with clinical trials showing that cure of infection can prevent duodenal ulcer and, to a lesser extent, gastric ulcer recurrence; cure early stage mucosa-associated lymphoid tissue lymphoma; and reduce the chances of developing gastric cancer in high-risk individuals.

Attack and defence in the gastric epithelium - a delicate balance

The gastric epithelium is a complex structure formed into tubular branched gastric glands. The glands contain a wide variety of cell types concerned with the secretion of hydrochloric acid, proteases, mucus and a range of signalling molecules. All cell types originate from stem cells in the neck region of the gland, before migrating and differentiating to assume their characteristic positions and functions. Endocrine and local paracrine mediators are of crucial importance for maintaining structural and functional integrity of the epithelium, in the face of a hostile luminal environment. The first such mediator to be recognized, the hormone gastrin, was identified over a century ago and is now established as the major physiological stimulant of gastric acid secretion. Recent studies, including those using mice that overexpress or lack the gastrin gene, suggest a number of previously unrecognized roles for this hormone in the regulation of cellular proliferation, migration and differentiation. This review focuses on the identification of hitherto unsuspected gastrin-regulated genes and discusses the paracrine cascades that contribute to the maintenance of gastric epithelial architecture and secretory function. Helicobacter infection is also considered in cases where it shares targets and signalling mechanisms with gastrin.

Using serum pepsinogens wisely in a clinical practice

Serum pepsinogen (PG) has been used as biomarkers of gastric inflammation and mucosal status, including atrophic change, before the discovery of Helicobacter pylori (H. pylori). Serum pepsinogen I (PG I) and pepsinogen II (PG II) levels are known to increase in the presence of H. pylori-related nonatrophic chronic gastritis. The measurement of serum PG provides much information on the presence of intestinal metaplasia as well as atrophic gastritis. The eradication of H. pylori provokes a significant change in serum PG values: it reduces both PG I and PG II and elevates the PG I to PG II ratio. Recently, the serum PG test method has been the first screening step in Japan, as well as photofluorography. Serum PG tests are used to screen for high risk subjects with atrophic gastritis, rather than as a test for cancer itself. Unlike photofluorography or endoscopy, serum PG screening can identify non-ulcerated differentiated asymptomatic cancer, irrespective of the size and location of the lesion. Most cases detected by the PG method are asymptomatic early gastric cancers and are limited to the mucosa, which are particularly well suited for endoscopic treatment. The PG method can contribute greatly to the patients' quality of life.

A comparative study of intragastric acidity during post-breakfast and pre-dinner administration of low-dose proton pump inhibitors: a randomized three-way crossover study

BACKGROUND

The absorption and bioavailability of proton pump inhibitors is influenced by food intake. Proton pump inhibitors bind to the parietal cell active proton pump, which is maximally stimulated after dinner: usually the largest meal of the day. However, it has not been fully clarified whether the efficacy of proton pump inhibitors differs between post-breakfast and pre-dinner dosing.

AIM

To perform a pH-monitoring study to clarify this issue for two low-dose proton pump inhibitors.

SUBJECTS AND METHODS

The subjects were 20 healthy male volunteers (seven Helicobacter pylori-positive and 13 H. pylori-negative), who were divided into two groups of 10 and administered 15 mg lansoprazole or 10 mg rabeprazole, respectively. All subjects underwent ambulatory intragastric 24-h pH- monitoring under three conditions allocated randomly: (i) without medication, (ii) seventh day of post-breakfast administration and (iii) eighth day of pre-dinner administration of each drug.

RESULTS

There was no significant difference in the percentage time during which pH > or =4.0 in the 24-h period between post-breakfast and pre-dinner administration of both drugs (56.6% vs. 55.8%; P = 0.557), although intragastric acidity during administration of both drugs was significantly lower than that without medication.

CONCLUSIONS

The timing of drug administration does not significantly influence the efficacy of low-dose proton pump inhibitors.

Tolerance to H2 receptor antagonist correlates well with the decline in efficacy against gastroesophageal reflux in patients with gastroesophageal reflux disease

BACKGROUND AND AIM

The attenuated antisecretory activity of H2 receptor antagonists (H2RA) during continuous administration is known as the tolerance phenomenon. The authors recently clarified that presence or absence of Helicobacter pylori infection influences the occurrence of the tolerance phenomenon. The aim of this study was to clarify whether tolerance to H2RA is correlated with attenuation of the inhibitory effect against gastroesophageal acid reflux in patients with gastroesophageal reflux disease (GERD).

METHODS

Ten male patients with GERD symptoms and abnormal gastroesophageal reflux were investigated by pH monitoring on days 1 and 15 of continuous oral famotidine administration at 20 mg twice daily, and H. pylori infection was examined using the urea breath test.

RESULTS

Intragastric and intraesophageal acidity were significantly decreased on the first day of famotidine administration, but then increased during the 15-day administration period in seven patients who were negative for H. pylori. In contrast, the efficacy of famotidine against gastric acid secretion and gastroesophageal acid reflux was not attenuated in three H. pylori-positive patients. The changes in GERD symptoms were correlated with the change in the degree of gastroesophageal reflux.

CONCLUSION

The presence or absence of tolerance to H2RA during 15-day administration is correlated with the efficacy for inhibition of gastroesophageal acid reflux.

Cholecystokinin and gastrin receptors

Cholecystokinin and gastrin receptors (CCK1R and CCK2R) are G protein-coupled receptors that have been the subject of intensive research in the last 10 years with corresponding advances in the understanding of their functioning and physiology. In this review, we first describe general properties of the receptors, such as the different signaling pathways used to exert short- and long-term effects and the structural data that explain their binding properties, activation, and regulation. We then focus on peripheral cholecystokinin receptors by describing their tissue distribution and physiological actions. Finally, pathophysiological peripheral actions of cholecystokinin receptors and their relevance in clinical disorders are reviewed.

Low pH and Helicobacter pylori increase nuclear factor kappa B binding in gastric epithelial cells: a common pathway for epithelial cell injury?

Helicobacter pylori infection results in peptic ulceration and chronic gastritis through mechanisms which are not fully elucidated. Live H. pylori activate the pro-inflammatory transcription factor NF-kappaB in gastric epithelial cells. Patients may have peptic ulcer disease in the absence of H. pylori infection; therefore other factors contribute to the inflammatory process. Maximal acid output in patients with H. pylori infection and duodenal ulceration is significantly increased indicating a role for acid in the pathogenesis of mucosal ulceration. The effect of low pH on NF-kappaB activation in gastric epithelial cells has not been studied. Human gastric epithelial cells (AGS) were exposed to a range of pH changes in the presence or absence of H. pylori. NF-kappaB DNA-binding and cytosolic IkappaB-alpha were measured using electrophoretic mobility shift assay and Western blotting. NF-kappaB DNA-binding in gastric epithelial cells dramatically increased when the pH of the culture medium decreased. Increases in NF-kappaB nuclear binding were paralleled by decreasing amounts of cytosolic IkappaB-alpha. These findings were similar but less potent than those observed when cells were exposed to H. pylori. Low pH resulted in enhancement of H. pylori-induced NF-kappaB nuclear binding. DNA binding of NF-kappaB activation secondary to low pH was attenuated by PD98059 but not by SB203580. Similar to H. pylori, low pH potently and independently augments NF-kappaB nuclear binding in AGS cells and such activation appears to be mediated through MEK1-dependant signaling pathways.

Helicobacter pylori infection influences symptomatic response to anti-secretory therapy in patients with GORD--crossover comparative study with famotidine and low-dose lansoprazole

BACKGROUND AND AIM

Helicobacter pylori infection was reported to affect gastric acid secretion. We investigated the heartburn symptoms of patients with gastro-oesophageal reflux disease during sequential treatment with 40 mg of famotidine or 15 mg of lansoprazole to clarify whether H. pylori infection influences symptomatic response to anti-secretory therapy.

SUBJECTS AND METHODS

The subjects were 33 gastro-oesophageal reflux disease patients, who had already been treated with a full dose of H2 receptor antagonist. First, famotidine at 20 mg b.i.d. was administered to the patients for 8 weeks. Second, famotidine was replaced with 15 mg of lansoprazole once in the morning for 8 weeks. Finally, 20 mg of famotidine was administered b.i.d. for 8 weeks instead of lansoprazole. Gastro-oesophageal reflux disease symptoms were assessed using an original visual analogue scale.

RESULTS

The sequential symptomatic responses to famotidine and lansoprazole administration indicated that gastro-oesophageal reflux disease symptoms of patients during low-dose lansoprazole treatment were significantly less than those during famotidine treatment. Remission of symptoms was obtained significantly more often by famotidine therapy in patients with H. pylori infection than in patients without H. pylori infection.

CONCLUSION

Low-dose lansoprazole is more effective than full-dose famotidine for the control of symptoms in patients with gastro-oesophageal reflux disease, and H. pylori infection influences the symptomatic response to H2 receptor antagonists.

Direct measurement of gastric H+/K+-ATPase activities in patients with or without Helicobacter pylori-associated chronic gastritis

AIM: The role of Helicobacter pylori (H pylori ) infection in gastric acid secretion of patients with chronic gastritis remains controversial. This study was designed to elucidate the effect of H pylori on H⁺/K⁺-ATPase activities in gastric biopsy specimens.

METHODS: Eighty-two patients with chronic gastritis who had undergone upper endoscopy were included in this study. H pylori infection was confirmed by rapid urease test and histology. Gastric H⁺/K⁺-ATPase activities and serum gastrin concentrations were measured by an enzymatic method and radioimmunoassay, respectively. For those patients who received triple therapy for eradicating H pylori, changes in the activity of gastric H⁺/K⁺-ATPase and serum gastrin levels were also measured.

RESULTS: The mean gastric H⁺/K⁺-ATPase activity in H pylori-positive group (42 patients) was slightly higher than that in H pylori-negative group (29 patients) (169.65±52.9 and 161.38±43.85 nmol P_i/(mg·h), respectively, P = 0.301). After eradication of H pylori, the gastric H⁺/K⁺-ATPase activities slightly decreased compared to prior therapy (165.03±59.50 and 158.42±38.93 nmol P_i/(mg·h), respectively, P = 0.805). The mean basal gastrin concentration was slightly higher in H pylori-positive patients than in H pylori-negative patients (87.92±39.65 pg/mL vs 75.04± 42.57 pg/mL, P = 0.228). The gastrin levels fell significantly after the eradication of H pylori. (Before treatment 87.00±30.78 pg/mL, after treatment 64.73±18.96 pg/mL, P = 0.015).

CONCLUSION: Gastric H⁺/K⁺-ATPase activities are not associated with H pylori status in patients with chronic gastritis.

Histamine-2 receptor expression in gastric mucosa before and after Helicobacter pylori cure

BACKGROUND

Helicobacter pylori infection prevents the occurrence of the tolerance phenomenon of Histamine-2 (H2) receptor antagonists. Gastro-esophageal reflux disease develops in some cases with the restoration of acid secretion after H. pylori eradication therapy.

AIM

To clarify the mechanisms of H2 receptor restoration after the eradication of H. pylori on parietal cells.

METHODS

We enrolled 80 consecutive asymptomatic male patients with H. pylori infection, having chronic gastritis with or without the presence of peptic ulcers. Biopsy specimens from the greater curvatures at the mid-corpus of the stomach were obtained endoscopically from all subjects before and 12 weeks after the eradication of H. pylori. Degrees of gastric atrophy were evaluated by serum pepsinogen levels. The amounts of mRNA expression of H2 receptor were evaluated in each subject's gastric mucosa by real time reverse transcriptase-polymerase chain reaction (RT-PCR).

RESULTS

H2 receptor mRNA expression levels significantly correlated with serum pepsinogens I and II ratios. The expression level of H2 receptor mRNA was lower in subjects with hypergastrinemia. The median expression level of H2 receptor after H. pylori eradication was threefold greater than prior to treatment. In addition, its restoration became more pronounced in subjects with severe gastric atrophy. However, a comparatively low restoration of H2 receptor mRNA was found in subjects with hypergastrinemia.

CONCLUSIONS

H2 receptor mRNA levels decrease with the progression of gastric atrophy induced by H. pylori infection, and are restored after H. pylori eradication. Such expression levels of H2 receptor may explain a part of the tolerance phenomenon to H2 receptor antagonists.

Restoration of heat shock protein70 suppresses gastric mucosal inducible nitric oxide synthase expression induced by Helicobacter pylori

Heat shock proteins (HSPs) are crucial for the maintenance of cell integrity during normal cellular growth as well as during pathophysiological conditions. While functioning mainly as molecular chaperones, HSPs also appear to be involved in diverse biological activities, such as apoptosis, carcinogenesis, and cytoprotection from cytotoxic damage. Infection with Helicobacter pylori causes inflammation in the gastric mucosa, leading to gastritis, gastric ulcers, duodenal ulcer disease, and even gastric cancer, but the role of HSPs in H. pylori-associated gastropathy is not known. Using two-dimensional electrophoretic analysis, we have observed significant shifts in HSP profiles after H. pylori infection in RGM-1 cells. We therefore evaluated the effect of treatments that induce HSPs on H. pylori-induced inducible nitric oxide synthase (iNOS) expression. We found that H. pylori infection significantly attenuated the expression of HSP70, whereas exposure of cells to noncytotoxic heat shock or geranylgeranylacetone restored HSP70 expression, as well as suppressing the expression of iNOS, a major cause of H. pylori-induced gastric tissue damage. Our results suggest that induction of HSP70 confers cytoprotection against H. pylori infection by inhibiting the expression of iNOS. In conclusion, these results provide important insights into the flux in HSPs profiles in response to H. pylori infection and highlight the cytoprotective role of HSP70 in H. pylori infection.

Clinical endocrinology and metabolism. Gastrin

The gastric hormone gastrin stimulates gastric acid secretion and epithelial cell proliferation. Multiple active products are generated from the precursor, preprogastrin, including the well-characterized amidated gastrins acting at the cholecystokinin-2 (CCK-2, or gastrin-CCK(B)) receptor, and others that may be growth factors in a range of cancers. Plasma concentrations of the amidated gastrins are elevated as a consequence of gastrin-secreting tumours (gastrinomas) and in conditions in which the normal inhibition of the antral G-cell by acid is depressed, for example chronic atrophic gastritis and prolonged treatment with proton pump inhibitors. There may also be increased gastrin release in Helicobacter pylori infection. Provocative tests for the diagnosis of gastrinoma include the secretin and calcium infusion tests. Hypergastrinaemia is associated with enterochromaffin-like (ECL) cell proliferation; the factors that determine progression to ECL cell dysplasia and gastric ECL cell carcinoid tumours are discussed. Several strategies for inhibiting the effects of gastrin are under evaluation, and their potential application is discussed.

Gastrin: old hormone, new functions

It is exactly a century since the gastric hormone gastrin was first described as a blood-borne regulator of gastric acid secretion. The identities of the main active forms of the hormone (the "classical gastrins") and their cellular and molecular sites of action in regulating acid secretion have all attracted sustained attention. However, recent work on peptides derived from the gastrin precursor that do not stimulate acid secretion ("non-classical gastrins"), together with studies on mice over-expressing the gene, or in which the gastrin gene has been deleted, suggest hitherto unsuspected roles in regulating cell proliferation, migration, and differentiation. Moreover, microarray and proteomic studies have identified previously unsuspected target genes of the classical gastrins. Some of the newer actions have implications for our understanding of the progression to cancer in oesophagus, stomach, pancreas and colon, all of which have recently been linked in one way or another to dysfunctional signalling involving products of the gastrin gene. The present review focuses on recent progress in understanding the biology of both classical and non-classical gastrins.

Helicobacter pylori infection prevents the occurrence of the tolerance phenomenon of histamine H2 receptor antagonists

BACKGROUND

The attenuated anti-secretory activity of H2 receptor antagonists (H2RA) during continuous administration is referred to as the tolerance phenomenon. However, it is not clarified whether Helicobacter pylori infection affects the occurrence of tolerance to H2RA. It is also not clarified whether the tolerance phenomenon occurs to a new H2RA, lafutidine.

AIM

To investigate the occurrence of the tolerance phenomenon in subjects with and without H. pylori infection during the continuous administration of lafutidine and famotidine.

SUBJECTS AND METHODS

Subjects were 20 healthy male volunteers (seven H. pylori positive and 13 H. pylori negative cases). All subjects were examined by ambulatory intragastric pH monitoring five times without medication, on the first and 15th day of the administration of 20 mg b.d. famotidine and 10 mg b.d. lafutidine in a cross-over fashion.

RESULTS

The tolerance phenomenon was not observed in H. pylori-positive subjects during the 15-day-long administration of both H2RAs. In contrast, the tolerance phenomenon was observed in H. pylori negative subjects, which has been previously reported.

CONCLUSIONS

This study demonstrated that H. pylori infection affects the tolerance phenomenon during continuous administration of H2RAs.

Improvement in serum pepsinogens and gastrin in long-term monitoring after eradication of Helicobacter pylori: comparison with H. pylori-negative patients

BACKGROUND

A decrease in pepsinogen and gastrin levels 1-3 months after Helicobacter pylori eradication is well known. However, few data are available on the long-term progression of these decreases beyond 1 year after eradication, and there has been no investigation into whether pepsinogen and gastrin levels return to normal levels as defined by data from H. pylori-negative patients with dyspepsia.

AIM

We studied the effect of H. pylori eradication on pepsinogen and gastrin levels for more than 1 year, and compared levels to those in H. pylori-negative patients with dyspepsia. We also investigated the effect of H. pylori eradication on the course of atrophic corpus gastritis as reflected by histology, and on PGI levels and PG I/II ratio.

METHODS

We enrolled 172 H. pylori-positive patients with dyspepsia who had undergone successful eradication therapy of more than 1 year's duration and 101 non-treated H. pylori-negative patients with dyspepsia. H. pylori status was assessed at entry and at each endoscopy after eradication by culture, histological results, the rapid urease test and the urea breath test. In both groups, patients were evaluated for fasting serum pepsinogen I and II and gastrin using a radioimmunoassay technique, and underwent detailed histological assessment according to the updated Sydney System.

RESULTS

In the H. pylori-negative patients, mean serum pepsinogen I and II, I/II ratio and gastrin levels were 52.6 +/- 20.8 ng/mL, 9.2 +/- 4.2 ng/mL, 6.0 +/- 1.7 and 53.5 +/- 29.2 pg/mL, respectively. In H. pylori-positive patients with long-term eradication, pepsinogen I and II, I/II ratio and gastrin levels were 81.3 +/- 46.6 ng/mL, 25.9 +/- 17.1 ng/mL, 3.4 +/- 1.3 and 131.9 +/- 130.8 pg/mL, respectively, before treatment. At 1-3 months after eradication, serum pepsinogen I and II levels in the H. pylori-positive patients decreased to levels similar to those in the negative patients, whereas pepsinogen I/II ratio and gastrin levels remained lower and higher, respectively, than in the negative patients. Serum pepsinogen I/II ratio and gastrin levels then became similar between the groups at 12-15 months after eradication. In histological findings, inflammation and neutrophil activity decreased by 1-3 months, and atrophy in the corpus and metaplasia in the antrum decreased by 12-15 months.

CONCLUSION

The results suggest that atrophic corpus gastritis and superficial gastritis are reversible, as indicated by both histological and serological findings in a long-term follow-up study.

Chronic Helicobacter pylori infection results in gastric hypoacidity and hypergastrinemia in wild-type mice but vagally induced hypersecretion in gastrin-deficient mice

Helicobacter pylori infection is a causal factor of gastric cancer (which is associated with low gastric acid secretion) or duodenal ulcer (high acid secretion). Parietal cells and ECL cells in the stomach are controlled by gastrin, which plays a crucial role in the regulation of acid secretion. The present study was undertaken to identify a possible role of gastrin in determining the different responses of the parietal cells and ECL cells to chronic H. pylori infection. Wild-type (C57BL/6J) gastrin(+/+) mice and gastrin(-/-) knockout mice, generated through targeted gene disruption and backcrossed eight times to C57BL/6J, were infected with H. pylori for 9 months. The acid output was measured 4 h after pylorus ligation (known to cause vagal excitation). The gastric mucosa was examined by immunocytochemistry with antisera to alpha-subunit of H+/K(+)-ATPase for the parietal cells, and to histamine and vesicle monoamine transporter-2 for the ECL cells, and by quantitative electron microscopy. In infected gastrin(+/+) mice, the acid output and the percentage of secreting parietal cells (freely fed state) were 20-30% of the values in uninfected controls, while the density and ultrastructure of parietal cells were normal. The infected mice had hypergastrinemia and displayed hypertrophy and hyperplasia of ECL cells. Although uninfected gastrin(-/-) mice had lower the acid output than uninfected gastrin(+/+) mice, there was a higher acid output (approximately 3 times) in infected gastrin(-/-) mice than their uninfected homologues. The numbers of parietal cells and ECL cells remained unchanged in infected gastrin(-/-) mice. In conclusion, chronic H. pylori infection results to impaired parietal-cell function (acid hyposecretion), hypergastrinemia and hyperplasia of ECL cells in wild-type mice but leads to vagally induced hypersecretion in gastrin-deficient mice.

Helicobacter pyloriInduces Plasminogen Activator Inhibitor 2 in Gastric Epithelial Cells through Nuclear Factor-κB and RhoA

The gastric pathogen Helicobacter pylori is associated with a progression to gastric cancer. The specific targets of H. pylori that might influence this progression are still unclear. Previous studies indicated that the gastric hormone gastrin, which may be increased in H. pylori infection, stimulates gastric expression of plasminogen activator inhibitor (PAI)-2, which is an inhibitor of the urokinase plasminogen activator and has previously been shown to be increased in gastric adenocarcinoma. Here, we report that H. pylori also increases PAI-2 expression. In gastric biopsies of H. pylori-positive subjects there was increased PAI-2, including subjects with plasma gastrin concentrations in the normal range. PAI-2 was expressed mainly in chief and mucous cells. In a gastric cancer cell line (AGS), H. pylori increased PAI-2 expression, which was associated with inhibition of H. pylori-stimulated cell invasion and apoptosis. The induction of PAI-2 by H. pylori was mediated by release of interleukin-8 and activation of cyclooxygenase-2, and interestingly, gastrin stimulated PAI-2 expression by similar paracrine pathways. The activation of NFkappaB was required for interleukin-8 and cyclooxygenase-2 activation but did not occur in cells responding to these paracrine mediators. The data suggest that induction of PAI-2 is a specific target in H. pylori infection, mediated at least partly by paracrine factors; induction of PAI-2 inhibits cell invasion and apoptosis and is a candidate for influencing the progression to gastric cancer.

New molecular targets for treatment of peptic ulcer disease

Most patients with peptic ulcer disease are currently treated with proton pump inhibitors or histamine H(2) receptor antagonists. The long-term use of these compounds has been associated with two potential problems. Firstly, proton pump inhibitors may induce enterochromaffin-like (ECL) cell hyperplasia. Secondly, ulcers may relapse despite maintenance therapy with histamine H(2) antagonists. This has been the rationale for the development of new antisecretory agents, including antagonists against gastrin and gastrin releasing peptide (GRP), as well as ligands to histamine H(3) receptors. Several potent, high affinity cholecystokinin (CCK)-2 receptor antagonists have recently been identified such as L-365260, YM-022, RP-73870, S-0509, spiroglumide and itriglumide (CR-2945). Current data suggest that they all have antisecretory and anti-ulcer effects. In addition to reducing acid production, CCK-2 receptor antagonists may possibly also accelerate gastric emptying, a combination of functions which could potentially be beneficial in patients with functional dyspepsia. Receptors for bombesin and its mammalian counterpart GRP have been localised in the brain, spinal cord and enteric nerve fibres of the gut as well as on secretory cells and smooth muscle cells of the intestinal tract. Current data clearly indicate that endogenous GRP is involved in the regulation of basal and postprandial acid secretion. However, at this stage it is not clear whether GRP agonists or GRP antagonists can be developed into useful drugs. The peptide has a wide range of biological effects and it is likely that analogues of GRP or antagonists of the peptide affect not only gastric acid secretion but also induce considerable side effects. Histamine plays a central role in the stimulation of acid secretion. After their detection in the brain, H(3) receptors have been identified in a variety of tissues including perivascular nerve terminals, enteric ganglia of the ileum and lung, and ECL cells. Despite many studies, the role of H(3) receptors in the regulation of gastric acid secretion is still unclear. Controversial data have been presented, and study results largely depend on the species and experimental models. It seems unlikely that proton pump inhibitors or H(2) receptor antagonists will be replaced in the near future by new antisecretory agents. The current shortcomings of the new compounds include mainly their reduced clinical effectiveness and pharmacological limitations. However, the development of these new antisecretory compounds provides interesting tools to assess the physiological and pharmacological role of different receptors within the gastrointestinal tract. The use of CCK-2 receptor antagonists in patients with functional dyspepsia and Zollinger-Ellison syndrome should be examined in randomised, controlled trials.