Does Helicobacter pylori-induced inflammation of gastric mucosa determine the severity of symptoms in functional dyspepsia?

Low-grade duodenal eosinophilia is associated with cagA in Helicobacter pylori-related dyspepsia

BACKGROUND AND AIM

Functional dyspepsia (FD) is a multifactorial disorder. Helicobacter pylori (H. pylori)-related dyspepsia (HpD) may be considered a separate entity. Duodenal eosinophilia is a potential pathogenic mechanism in FD. However, the impact of duodenal eosinophilia and H. pylori virulence genes in HpD was not explored. We aim to evaluate the association of H. pylori virulence genes and low-grade duodenal eosinophilia in HpD.

METHODS

A multi-center cross-sectional study was conducted. A total of 301 patients who meet Rome-III criteria were selected before upper endoscopy, and 95 patients were included after normal endoscopy and positive H. pylori in gastric biopsies were assessed. Clinical parameters, H. pylori virulence genes (cagA, oipA, and vacA) and duodenal histology were evaluated.

RESULTS

Sixty-nine (72%) patients had epigastric pain syndrome (EPS), 17 (18%) post-prandial distress syndrome (PDS) and 9 (10%) EPS/PDS overlap. FD syndromes were not associated with cagA or oipA strains. A significantly trend of vacA s1/m1 (78%) and s1/m2 (80%) positive strains in EPS was observed. Histological duodenal grading of chronic inflammation, low-grade duodenal eosinophilia and intra-epithelial lymphocytes showed no difference in oipA and vacA strains. Low-grade duodenal eosinophilia was significant in cagA positive strain, and the OR for low-grade duodenal eosinophilia with H. pylori cagA positive strain was 4.2 (95% CI, 1.78-9.93). Adjusting for age, gender, smoking, diabetes, alcohol, PPI, and NSAID, the OR was 5.44 (1.989-14.902).

CONCLUSION

Our findings suggest that low-grade duodenal eosinophilia is significantly associated with cagA strain in HpD.

Zhizhu Kuanzhong Capsule in treating patients with functional dyspepsia postprandial distress syndrome: study protocol for a multicenter, randomized, double-blind, placebo-controlled, parallel-group clinical trial

Background

Functional dyspepsia (FD) is one of the most common functional gastrointestinal disorders. Based on the various symptoms present in patients with functional dyspepsia postprandial distress syndrome (FD-PDS), routine agents such as acid suppressants, prokinetic drugs, and centrally acting drugs, offer limited treatment choices with potential side effects. As a preliminary clinical trial showed that the marketed product Zhizhu Kuanzhong Capsule (ZZKZ) can improve symptoms in FD-PDS patients, our study aims to provide further evidence on the clinical efficacy and safety of ZZKZ in the treatment of patients with FD-PDS.

Methods

In this multicenter, randomized, patient- and investigator-blinded, placebo-controlled, parallel-group clinical trial, we will recruit patients with FD-PDS from 18 hospitals in China and Australia. The trial will enroll patients with FD-PDS based on the Rome IV diagnostic criteria. A total of 480 eligible patients will be randomized 1:1 into either ZZKZ or placebo group with 8 weeks of treatment and 4 weeks of follow-up. The primary endpoint will be measured by a self-rated Visual Analogue Score (VAS) for the degree of discomfort with both symptoms of postprandial fullness and early satiation, recorded once a day and 7 days a week. The primary analysis will aim to compare the response rate for FD-PDS VAS score between the groups before and after 8 weeks of treatment with an alpha level of 0.05 (2-sided).

Discussion

This trial aims to strengthen the evidence for the efficacy and safety of ZZKZ, a marketed product, in treating FD-PDS. Compared to the previous clinical trial that targeted FD-PDS, this trial will have an 8-week double-blind treatment period to investigate the effect of long-term mediation through comparison with the placebo group.

Trial registration

ClinicalTrials.gov NCT03825692. Registered on 28 January 2019

Supplementary Information

The online version contains supplementary material available at 10.1186/s13063-022-06396-5.

Quercetin Improves Mitochondrial Function and Inflammation in H2O2-Induced Oxidative Stress Damage in the Gastric Mucosal Epithelial Cell by Regulating the PI3K/AKT Signaling Pathway

Functional dyspepsia (FD) is one of the most common functional gastrointestinal disorders, the therapeutic strategy of which it is limited due to its complex pathogenesis. Oxidative stress-induced damage in gastric mucosal epithelial cells is related to the pathogenesis and development of FD. Quercetin (Que) is one of the active ingredients of Zhishi that showed antioxidant, antiapoptotic, and anti-inflammatory effects. The aim of this study is to investigate the effect of Que on oxidative stress-induced gastric mucosal epithelial cells damage and its underlying molecular mechanism. The gastric mucosal epithelial cell line GES-1 was treated with 200 μM of H₂O₂ to construct an oxidative stress-induced damage model. The H₂O₂ cells were then administrated with different concentrations of Que. The results indicated that high concentration of Que (100 μM) showed cytotoxicity in H₂O₂-induced GES-1 cells. However, appropriate concentration of Que (25 and 50 μM) alleviated the oxidative stress damage induced by H₂O₂, as demonstrated by the increase of proliferation, decrease of ROS generation, apoptosis, inflammation, and alleviation of mitochondrial function and cell barrier. In addition, Que increased the activation of phosphorylation of PI3K and AKT decreased by H₂O₂. To investigate whether Que alleviated the oxidative stress damage in GES-1 cells by the PI3K/AKT signaling pathway, the GES-1 cells were treated with Que (25 μM) combined with and without LY294002, the PI3K inhibitor. The results showed that LY294002 suppressed the alleviation effect on Que in H₂O₂-induced GES-1 cells. In conclusion, the current study demonstrates that Que alleviates oxidative stress damage in GES-1 cells by improving mitochondrial function and mucosal barrier and suppressing inflammation through regulating the PI3K/AKT signaling pathway, indicating the potential therapeutic effects of Que on FD.

Functional Dyspepsia: Diagnostic and Therapeutic Approaches

Functional dyspepsia is a common functional gastrointestinal (GI) disorder of gastroduodenal origin, diagnosed clinically in the presence of prototypical symptoms of epigastric pain and meal-related symptoms, and without structural explanation. The most recent diagnostic criteria provide for two functional dyspepsia subtypes, epigastric pain syndrome (EPS) and post-prandial distress syndrome (PDS) based on the predominant symptom pattern. The evaluation of dyspepsia should keep laboratory, imaging, and invasive testing to a minimum, as extensive or repetitive investigations are of rather low diagnostic yield in the absence of localizing symptoms or alarm features. Factors with etiopathologic relationships to functional dyspepsia include micro-inflammation, GI infections, abnormalities of gastroduodenal motility, visceral hypersensitivity, disturbances along the brain-gut axis, and psychological factors; all of these causative mechanisms have potential to partially explain symptoms in some functional dyspepsia patients, thus providing a rationale for the efficacy of a diversity of therapeutic approaches to functional dyspepsia. Management of dyspepsia symptoms relies upon both pharmacologic treatments and non-pharmacologic approaches, including psychological and complementary interventions. The evidence in support of established functional dyspepsia therapies is reviewed, and forms the basis for an effective functional dyspepsia treatment strategy emphasizing the patient's current symptom severity, pattern, and impact on the function and quality of life of the individual.

Comparison of clinical symptoms after Helicobacter pylori eradication in functional dyspepsia patients based on endoscopic view of antral gastropathy

Functional dyspepsia is a common gastric disease that can be associated with Helicobacter pylori infection. The aim of this study is to evaluate antral endoscopy of individuals who presented with functional dyspepsia, H. pylori infection status and the effects of eradication therapy on the symptoms. Following the diagnosis of dyspepsia as per Rome III criteria, 260 individuals who were eligible for the study underwent upper gastrointestinal endoscopy and were divided into four groups of 65 according to the endoscopic view, grades I, II, III and IV (negative). Stool antigen test was also performed for all patients to identify H. pylori infection. The early signs of dyspepsia were assessed by a standard questionnaire. In all groups, omeprazole, amoxicillin, clarithromycin and metronidazole were used for eradication treatment, and 1 month after the treatment, a faecal antigen test was repeated to evaluate the eradication of H. pylori. There was no statistically significant difference between the groups in terms of clinical symptoms before treatment. The highest response to eradication treatment was seen in individuals with antral gastropathy grade III (66.2%) and the lowest response was in patients without antral gastropathy Grade IV (32.3%). This difference was statistically significant. There was no statistically significant relationship between the participants in terms of family history, age, gender and response to treatment. Eradicating H. pylori reduces the symptoms of dyspepsia. The response of eradication therapy was greatest among the patients with grade III antral gastropathy.

Weikangning therapy in functional dyspepsia and the protective role of Nrf2

Functional dyspepsia (FD) is a non-organic gastrointestinal disorder that has a marked negative impact on quality of life. Compared with conventional pharmacological therapies, the traditional Chinese medicine weikangning (WKN) is a safe and effective treatment for FD. The present study aimed to determine the molecular mechanisms underlying the efficacy of WKN. The effect of different concentrations of WKN on the proliferation of the human gastric mucosal epithelial cell line GES-1 was assessed. The optimal WKN concentration to promote cell proliferation was determined, and this concentration was used to examine the effect of WKN compared with a domperidone-treated positive control group on the antioxidant capacity of GES-1 cells. The effect of WKN treatment on the growth and antioxidant activity of GES-1 cells was also assessed following nuclear factor erythroid 2 like 2 (Nrf2) knockdown. The optimal WKN dose for promoting cell growth was determined to be 0.025 mg/ml; at this concentration the expression of the antioxidant proteins glutathione S-transferase P and superoxide dismutase 2 (SOD2) were significantly elevated (P<0.0001). Furthermore, the amount of reduced glutathione and activity of SOD2 were significantly increased (P<0.0001 and P<0.01, respectively), and malondialdehyde content was significantly decreased, compared with the controls (P<0.001). With WKN treatment, the transcription of Nrf2 and its downstream genes were significantly upregulated (P<0.01), and the level and nuclear distribution of Nrf2 protein was also markedly increased. Following Nrf2 silencing, the protective antioxidant effects of WKN treatment were impaired and GES-1 cell proliferation decreased. The results of the present study suggest that the efficacy of WKN in protecting gastric mucosal epithelial cells in FD is antioxidant-dependent and mediated by Nrf2 activation.

The Role of H. pylori CagA in Regulating Hormones of Functional Dyspepsia Patients

Helicobacter pylori (H. pylori, Hp) colonizes the stomachs of approximately 20%–80% of humans throughout the world. The Word Healthy Organization (WHO) classified H. pylori as a group 1 carcinogenic factor in 1994. Recently, an increasing number of studies has shown an association between H. pylori infection and various extragastric diseases. Functional dyspepsia (FD) is considered a biopsychosocial disorder with multifactorial pathogenesis, and studies have shown that infection with CagA-positive H. pylori strains could explain some of the symptoms of functional dyspepsia. Moreover, CagA-positive H. pylori strains have been shown to affect the secretion of several hormones, including 5-HT, ghrelin, dopamine, and gastrin, and altered levels of these hormones might be the cause of the psychological disorders of functional dyspepsia patients. This review describes the mutual effects of H. pylori and hormones in functional dyspepsia and provides new insight into the pathogenesis of functional dyspepsia.

Paediatric Rome III Criteria-Related Abdominal Pain Is Associated With Helicobacter pylori and Not With Calprotectin

OBJECTIVES

Abdominal pain-related functional gastrointestinal disorders in children include functional dyspepsia, functional abdominal pain, irritable bowel syndrome, and abdominal migraine. We aimed to evaluate a possible association between functional abdominal pain disorders and Helicobacter pylori infection and faecal calprotectin level.

METHODS

Prospective observational study including consecutive children with functional gastrointestinal disorders fulfilling Rome III criteria (cases) and age/sex-matched healthy controls. H pylori has been detected by biopsy-based tests and stool-antigen detection, faecal calprotectin by enzyme-linked immunosorbent assay.

RESULTS

A total of 56 cases (27 with functional dyspepsia) and 56 controls were enrolled. H pylori being detected in 17 of 56 cases (30.4%) and 4 of 56 controls (7.1%, odds ratio: 5.7; 95% confidence interval [CI]: 1.8-18.2, P = 0.003). H pylori was detected significantly more frequently in cases with functional dyspepsia (14/27, 51.9% odds ratio: 14.0; 95% CI: 3.9-49.7, P = 0.00001) than in controls and not in cases with other well-recognized functional gastrointestinal complaints (3/29, 10.3%). The median faecal calprotectin level was similar in cases (7.8 μg/g, 95% CI: 7.8-8.4) including those with gastritis, and controls (9.1 μg/g, 95% CI: 7.8-11.3). Gastritis features were more frequent in H pylori-infected and noninfected cases with functional dyspepsia (27/27, 100%) than in cases with other abdominal functional complaints (15/29, 51.7%, P = 0.007).

CONCLUSIONS

H pylori gastritis and noninfectious gastritis were associated with functional dyspepsia in children referred for abdominal pain-related functional gastrointestinal disorders while faecal calprotectin is not a predictor of gastritis and is similar in children with functional abdominal pain symptoms and in controls.

Distinct aetiopathogenesis in subgroups of functional dyspepsia according to the Rome III criteria

BACKGROUND AND OBJECTIVE

Whether there is distinct pathogenesis in subgroups of functional dyspepsia (FD), the postprandial distress syndrome (PDS) and epigastric pain syndrome (EPS) remains controversial. We aimed to identify the risk factors of FD and its subgroups in the Chinese population.

METHODS

Patients with dyspepsia and healthy subjects who underwent gastric cancer screening were enrolled in this multicentre study from 2010 to 2012. All patients were evaluated by questionnaire, oesophagoduodenoscopy, histological examination and Helicobacter pylori tests. Subgroups of FD were classified according to the Rome III criteria. Psychiatric stress was assessed by the short form Brief Symptom Rating Scale. CagA and VacA genotypes were determined by PCR.

RESULTS

Of 2378 patients screened for eligibility, 771 and 491 fulfilled the diagnostic criteria of uninvestigated dyspepsia and FD, respectively. 298 (60.7%) and 353 (71.9%) individuals were diagnosed with EPS and PDS, respectively, whereas 169 (34.4%) had the overlap syndrome. As compared with 1031 healthy controls, PDS and EPS shared some common risk factors, including younger age (OR 0.95; 99.5% CI 0.93 to 0.98), non-steroidal anti-inflammatory drugs (OR 6.60; 99.5% CI 3.13 to 13.90), anxiety (OR 3.41; 99.5% CI 2.01 to 5.77) and concomitant IBS (OR 6.89; 99.5% CI 3.41 to 13.94). By contrast, H. pylori (OR 1.86; 99.5% CI 1.01 to 3.45), unmarried status (OR 4.22; 99.5% CI 2.02 to 8.81), sleep disturbance (OR 2.56; 99.5% CI 1.29 to 5.07) and depression (OR 2.34; 99.5% CI 1.04 to 5.36) were associated with PDS. Moderate to severe antral atrophy and CagA positive strains were also more prevalent in PDS.

CONCLUSIONS

Different risk factors exist among FD subgroups based on the Rome III criteria, indicating distinct aetiopathogenesis of the subdivisions that may necessitate different therapeutic strategies.

Systematic review with meta-analysis: post-infectious functional dyspepsia

BACKGROUND

The prevalence of functional dyspepsia (FD) following infectious gastroenteritis has not been systematically reviewed.

AIM

To conduct a systematic review and calculate the summary odds ratio (OR) for the development of FD following infectious gastroenteritis, as compared to a control population.

METHODS

Published studies in PubMed, EmBASE, and Cochrane Database and abstracts from standard sources were screened for eligible studies. Data from studies meeting inclusion criteria were pooled for meta-analysis.

RESULTS

Nineteen studies were eligible for inclusion. The mean prevalence of FD following acute gastroenteritis (AGE) was 9.55% (FD, n = 909; AGE, n = 9517) in adult populations. The summary OR for the development of post-infectious FD was 2.54 (95% CI = 1.76-3.65) at more than 6 months after AGE, as compared to the prevalence in controls within the same population. This is compared with the summary OR (3.51; 95% CI = 2.05-6.00) for the development of post-infectious irritable bowel syndrome (IBS) in the same population at more than 6 months after AGE. There was significant statistical heterogeneity with an I(2) of 72.8% for the summary OR of post-infectious FD. Several pathogens, including Salmonella spp., Escherichia coli O157, Campylobacter jejuni, Giardia lamblia and Norovirus have been shown to be associated with post-infectious FD symptoms.

CONCLUSIONS

Infectious gastroenteritis is associated with an increased risk for subsequent dyspepsia as well as for irritable bowel syndrome. Post-infectious FD and post-infectious irritable bowel syndrome may represent different aspects of the same pathophysiology. Further studies will be needed to determine this.

Rome III criteria cannot distinguish patients with chronic gastritis from those functional dyspepsia patients

BACKGROUND

Functional dyspepsia is thought to be a diagnosis made after excluding endoscopically detectable lesions by the current Rome III criteria. However, whether these "functional dyspepsia" patients were diagnosed appropriately is still controversial.

MATERIALS AND METHODS

A total of 223 patients diagnosed with functional dyspepsia by Rome III criteria were enrolled. All patients were submitted to endoscopic examination, rapid urease test, and histologic evaluation. We also appraised the effect of a 7-day treatment based on the Glasgow Dyspepsia Severity Score.

RESULTS

Helicobacter pylori infection and neutrophil infiltration were found in 37.7% and 36.3% cases, respectively, and were both more frequent in the subgroup with epigastric pain symptom (EPS) than in the other two subgroups. In addition, neutrophil infiltration was more common and severe in the H. pylori-positive individuals than in the patients without infection (Mann-Whitney U-test = 431.500, p < .001). The treatment was useful in symptom improvement of all three subgroups, and the EPS subgroup had the greatest change of symptom scores before and after treatment as compared with the subgroup with postprandial distress symptom (PDS) and PDS/EPS subgroup (χ(2) = 42.745, p < .001), and the eradication of H. pylori revealed a statistical significant difference in different subgroups (χ(2) = 11.300, p = .001).

CONCLUSIONS

Our findings showed that many H. pylori-positive subjects diagnosed as "functional dyspepsia" were actually chronic gastritis patients, especially the EPS cases who are more likely to be patients with "active gastritis under microscope," and also benefit most from the treatment of proton-pump inhibitors or eradication of H. pylori.

Effect of Helicobacter pylori Eradication on Functional Dyspepsia

Background/Aims

This study evaluated the effect of Helicobacter pylori eradication on functional dyspepsia (FD), and the relationship between the changes of histological gastritis and FD symptom responses.

Methods

A total of 213 FD patients diagnosed by Rome III criteria were consecutively enrolled. H. pylori tests and gastritis grade by the Sydney system were performed before and 1 year after the proton pump based-eradication therapy for 7 days. Serum levels of pepsinogen, and genetic polymorphisms IL-6, IL-8 and IL-10 were investigated.

Results

Total of 91 patients completed the 1 year follow-up. When the response rate of dyspepsia was compared at 1 year between the non-eradicated group (n = 24) and eradicated group (n = 67), each group showed complete response of 62.5% and 62.7%; satisfactory response (≥ 50%) of 0.0% and 19.4%; partial response (< 50%) of 12.5% and 11.9%; and refractory response of 25.0% and 6.0%, respectively (P = 0.015). In addition, the responder group (complete + satisfactory response) at 1 year showed improvement of activity and chronic inflammation in both the antrum and corpus (all P < 0.001). Multivariate analysis showed that H. pylori eradication (OR, 5.81; 95% CI, 1.07-31.59) and symptom improvement at 3 month (OR, 28.90; 95% CI, 5.29-157.82) were associated with the improvement of dyspepsia at 1 year. Among the successfully eradicated FD patients (n = 67), male (P = 0.013) and higher initial BMI (P = 0.016) were associated with the improvement of dyspepsia at 1 year.

Conclusions

H. pylori eradication improved FD symptoms, as well as gastritis at 1 year, suggesting that inflammation mediates FD.

Should we still subcategorize helicobacter pylori-associated dyspepsia as functional disease?

Functional dyspepsia is a group of disorders featuring symptoms believed to be derived from the stomach and duodenum such as upper abdominal discomfort, pain, postprandial fullness and early satiety. A key diagnostic requisite is the absence of organic, metabolic, or systemic disorders to explain "dyspeptic symptoms." Therefore, when peptic ulcer diseases (including scars), erosive esophagitis and upper gastrointestinal malignancies are found at endoscopic examinations, the diagnosis of functional dyspepsia is excluded. One notable exception, however, is Helicobacter pylori infection. According to the Rome III definition, H. pylori infection is included in functional dyspepsia. This is an obvious deviation from the diagnostic principle of functional dyspepsia, since H. pylori infection is a definite cause of mucosal inflammation, which affects a number of important gastric physiologies such as acid secretion, gastric endocrine function and motility. The chronic persistent nature of infection also results in more dramatic mucosal changes such as atrophy or intestinal metaplasia, the presence of which in the esophagus (Barrett's esophagus) precludes the diagnosis of functional dyspepsia. Since careful endoscopic examination can diagnose reliably H. pylori infection not only in Japan but also in Western contries, it is now feasible and more logical to exclude patients with chronic gastritis caused by H. pylori infection as having dyspeptic symptoms. It is time to establish the Asian consensus to declare that H. pylori infection should be separated from functional dyspepsia.

Symptom-based tendencies of Helicobacter pylori eradication in patients with functional dyspepsia

AIM: To investigate whether there were symptom-based tendencies in the Helicobacter pylori (H. pylori) eradication in functional dyspepsia (FD) patients.

METHODS: A randomized, single-blind, placebo-controlled study of H. pylori eradication for FD was conducted. A total of 195 FD patients with H. pylori infection were divided into two groups: 98 patients in the treatment group were treated with rabeprazole 10 mg twice daily for 2 wk, amoxicillin 1.0 g and clarithromycin 0.5 g twice daily for 1 wk; 97 patients in the placebo group were given placebos as control. Symptoms of FD, such as postprandial fullness, early satiety, nausea, belching, epigastric pain and epigastric burning, were assessed 3 mo after H. pylori eradication.

RESULTS: By per-protocol analysis in patients with successful H. pylori eradication, higher effective rates of 77.2% and 82% were achieved in the patients with epigastric pain and epigastric burning than those in the placebo group (P < 0.05). The effective rates for postprandial fullness, early satiety, nausea and belching were 46%, 36%, 52.5% and 33.3%, respectively, and there was no significant difference from the placebo group (39.3%, 27.1%, 39.1% and 31.4%) (P > 0.05). In 84 patients who received H. pylori eradication therapy, the effective rates for epigastric pain (73.8%) and epigastric burning (80.7%) were higher than those in the placebo group (P < 0.05). The effective rates for postprandial fullness, early satiety, nausea and belching were 41.4%, 33.3%, 50% and 31.4%, respectively, and did not differ from those in the placebo group (P > 0.05). By intention-to-treat analysis, patients with epigastric pain and epigastric burning in the treatment group achieved higher effective rates of 60.8% and 65.7% than the placebo group (33.3% and 31.8%) (P < 0.05). The effective rates for postprandial fullness, early satiety, nausea and belching were 34.8%, 27.9%, 41.1% and 26.7% respectively in the treatment group, with no significant difference from those in the placebo group (34.8%, 23.9%, 35.3% and 27.1%) (P > 0.05).

CONCLUSION: The efficacy of H. pylori eradication has symptom-based tendencies in FD patients. It may be effective in the subgroup of FD patients with epigastric pain syndrome.

What is the difference between Helicobacter pylori-associated dyspepsia and functional dyspepsia?

Advances in basic and clinical research have revealed that Helicobacter pylori (H. pylori) infection plays an important role in the development of gastroduodenal dysmotility and hypersensitivity, as also in dyspepsia symptoms. In addition, recent studies have proposed an inflammation-immunological model for the pathogenesis of functional dyspepsia. Since H. pylori is the major microbe that provokes a gastroduodenal inflammatory response, it should not be overlooked when considering the pathophysiology of dyspepsia symptoms. In fact, population-based studies have demonstrated that H. pylori is detected more frequently in dyspepsia patients. However, although many clinical studies tried to reveal the association of H. pylori infection with gastric motility dysfunction or hypersensitivity, the results have been conflicting. On the other hand, many etiological features were revealed for the development of H. pylori-associated dyspepsia, such as abnormal ghrelin or leptic secretion, altered expression of muscle-specific microRNAs, and duodenal inflammatory cell infiltration. In addition, therapeutic strategy for H. pylori-associated dyspepsia would be different from H. pylori-negative functional dyspepsia. This review focuses the issue of whether H. pylori-associated dyspepsia should be considered as a different disease entity from functional dyspepsia.