Changes in the human gut microbiota composition caused by Helicobacter pylori eradication therapy: A systematic review and meta-analysis

Indole-3-Lactic Acid Derived from Lacticaseibacillus paracasei Inhibits Helicobacter pylori Infection via Destruction of Bacteria Cells, Protection of Gastric Mucosa Epithelial Cells, and Alleviation of Inflammation

Indole-3-lactic acid (ILA) has exhibited antimicrobial properties. However, its role in inhibiting Helicobacter pylori infection remains elusive. This study investigated the inhibitory effect of ILA produced by Lacticaseibacillus paracasei on H. pylori, which was further confirmed by cell and animal experiments. 5 mg/mL ILA was sufficient to directly inhibit the growth of H. pylori in vitro, with a urease inhibitory activity reaching 60.94 ± 1.03%, and the cell morphology and structure were destroyed. ILA inhibited 56.5% adhesion of H. pylori to GES-1 and significantly reduced the number of apoptotic cells. Furthermore, ILA suppresses H. pylori colonization by approximately 38% to 63%, reduced inflammation and oxidative stress in H. pylori-infected mice, and enhanced the enrichment and variety of gut microbiota, notably fostering the growth of beneficial bacteria such as Lactobacillus and Bifidobacterium strains. The results support that ILA derived from Lactobacillus can be applicated as a novel prebiotic in anti-H. pylori functional foods.

Structure-based design of small molecule inhibitors of the cagT4SS ATPase Cagα of Helicobacter pylori

We here describe the structure-based design of small molecule inhibitors of the type IV secretion system of Helicobacter pylori. The secretion system is encoded by the cag pathogenicity island, and we chose Cagα, a hexameric ATPase and member of the family of VirB11-like proteins, as target for inhibitor design. We first solved the crystal structure of Cagα in a complex with the previously identified small molecule inhibitor 1G2. The molecule binds at the interface between two Cagα subunits and mutagenesis of the binding site identified Cagα residues F39 and R73 as critical for 1G2 binding. Based on the inhibitor binding site we synthesized 98 small molecule derivates of 1G2 to improve binding of the inhibitor. We used the production of interleukin-8 of gastric cancer cells during H. pylori infection to screen the potency of inhibitors and we identified five molecules (1G2_1313, 1G2_1338, 1G2_2886, 1G2_2889, and 1G2_2902) that have similar or higher potency than 1G2. Differential scanning fluorimetry suggested that these five molecules bind Cagα, and enzyme assays demonstrated that some are more potent ATPase inhibitors than 1G2. Finally, scanning electron microscopy revealed that 1G2 and its derivatives inhibit the assembly of T4SS-determined extracellular pili suggesting a mechanism for their anti-virulence effect.

A review for non-antibiotic treatment of Helicobacter pylori: new insight

Gastric ulcers and gastric cancer are brought on by the Helicobacter pylori bacteria, which colonizes under the stomach mucous membrane. Different medication regimens are used to remove it, but the illness returns and becomes more resistant, which lowers the treatment rates. Additionally, this bacterium now exhibits a skyrocketing level of multi-drug resistance, necessitating recurrent therapeutic treatments. The negative effects of synthetic medications in comparison to conventional therapies are another significant factor in favor of non-pharmacological therapy. The most significant side effects of popular anti-gastric ulcer medications include nausea, vomiting, and diarrhea. Stomach ulcers have previously been treated with herbal remedies and complementary treatments like probiotics. When probiotics are ingested, the host experiences several advantages that may be brought about by altering the bacterial flora in the digestive system. Additionally, stronger-acting chemical compounds and plant extracts can be employed to treat patients. In this article, we look at the substances and medications that are utilized in place of synthetic stomach ulcer-curing treatments.

The effect of supplementing with Saccharomyces boulardii on bismuth quadruple therapy for eradicating Helicobacter pylori: a systematic review and meta-analysis of randomized controlled trials

Background and objective

It remains uncertain if the addition of Saccharomyces boulardii (S. boulardii) to bismuth quadruple therapy (BQT) recommended in the current guidelines can enhance the Helicobacter pylori (H. pylori) eradication rate and decrease the incidence of adverse events. We therefore conducted a meta-analysis of randomized controlled trials (RCTs) to address this issue.

Methods

We performed comprehensive searches in PubMed, Embase, Web of Science, and Cochrane library databases from the inception of the databases through to November 1, 2023. A meta-analysis was conducted to determine the pooled relative risk (RR) with 95% confidence intervals (CI) using a random-effects model. We utilized the revised Cochrane Risk of Bias Tool to assess the risk of bias of included studies.

Results

A total of six RCTs (1,404 patients) included in this meta-analysis. The results of the intention-to-treat analysis showed that the combination of S. boulardii with BQT had a higher eradication rate than BQT alone (87.0% versus 83.3%), with a pooled RR of 1.05 (95% CI: 1.00-1.10, p = 0.03). In the per-protocol analysis, however, there was no statistical significance between the two groups in the eradication rate (93.7% versus 91.0%, RR = 1.03, 95% CI: 1.00-1.06, p = 0.07). The combination of S. boulardii and BQT had a significantly lower rate of overall adverse events (22% vs. 39%, RR = 0.56, 95% CI: 0.44-0.70, p < 0.00001), diarrhea (7.9% vs. 25.7%, RR = 0.29, 95% CI: 0.17-0.48, p < 0.00001), constipation (2.9% vs. 8.4%, RR = 0.35, 95% CI: 0.14-0.88, p = 0.03) and abdominal distention (4.9% vs. 12.7%, RR = 0.41, 95% CI: 0.23-0.72, p = 0.002) than BQT alone. For the assessment of risk of bias, five studies were deemed to have some concerns, while one study was judged to have a low risk.

Conclusion

Current evidence suggests that supplementation with S. boulardii in BQT may not have a major effect on the H. pylori eradication rate, but significantly reduces the incidence of overall adverse events, diarrhea, abdominal distention and constipation. Combining S. Boulardii with BQT can help alleviate symptoms, potentially improving patient adherence.

Systematic review registration

https://osf.io/n9z7c.

Life at the borderlands: microbiomes of interfaces critical to One Health

Microbiomes are foundational components of the environment that provide essential services relating to food security, carbon sequestration, human health, and the overall well-being of ecosystems. Microbiota exert their effects primarily through complex interactions at interfaces with their plant, animal, and human hosts, as well as within the soil environment. This review aims to explore the ecological, evolutionary, and molecular processes governing the establishment and function of microbiome-host relationships, specifically at interfaces critical to One Health-a transdisciplinary framework that recognizes that the health outcomes of people, animals, plants, and the environment are tightly interconnected. Within the context of One Health, the core principles underpinning microbiome assembly will be discussed in detail, including biofilm formation, microbial recruitment strategies, mechanisms of microbial attachment, community succession, and the effect these processes have on host function and health. Finally, this review will catalogue recent advances in microbiology and microbial ecology methods that can be used to profile microbial interfaces, with particular attention to multi-omic, advanced imaging, and modelling approaches. These technologies are essential for delineating the general and specific principles governing microbiome assembly and functions, mapping microbial interconnectivity across varying spatial and temporal scales, and for the establishment of predictive frameworks that will guide the development of targeted microbiome-interventions to deliver One Health outcomes.

Update on the association between Helicobacter pylori infection and asthma in terms of microbiota and immunity

H. pylori is a gram-negative bacterium that is usually acquired in childhood and can persistently colonize the gastric mucosa of humans, affecting approximately half of the world's population. In recent years, the prevalence of H. pylori infection has steadily reduced while the risk of allergic diseases has steadily climbed. As a result, epidemiological research indicates a strong negative association between the two. Moreover, numerous experimental studies have demonstrated that eradicating H. pylori increases the risk of allergic diseases. Hence, it is hypothesized that H. pylori infection may act as a safeguard against allergic diseases. The hygiene hypothesis, alterations in gut microbiota, the development of tolerogenic dendritic cells, and helper T cells could all be involved in H. pylori's ability to protect against asthma. Furthermore, Studies on mice models have indicated that H. pylori and its extracts are crucial in the management of asthma. We reviewed the in-depth studies on the most recent developments in the relationship between H. pylori infection and allergic diseases, and we discussed potential mechanisms of the infection's protective effect on asthma in terms of microbiota and immunity. We also investigated the prospect of the application of H. pylori and its related components in asthma, so as to provide a new perspective for the prevention or treatment of allergic diseases.

Research trends on the relationship between Helicobacter pylori and microbiota: A bibliometric analysis

BACKGROUND

Increasing evidence has indicated that Helicobacter pylori infection is associated with the complex microbiota in the digestive tract of the human body. We aimed to assess the research trends and hotspots in the field of H. pylori and microbiota using a quantitative method.

MATERIALS AND METHODS

The clinical studies on H. pylori and microbiota published from 2001 to 2022 were extracted from the Web of Science database. We visualized and analyzed countries/regions, institutions, authors, journals, and keywords through VOSviewer and CiteSpace software. The test techniques, specimen type, as well as microbiota variation after H. pylori infection and eradication were also evaluated.

RESULTS

A total of 98 publications were finally identified, and the number of annual papers increased gradually. China showed its dominant position in the publication outputs, and Nanchang University was the most productive institution. Cong He, Xu Shu, and Yin Zhu published the highest number of papers, whereas Helicobacter was the most productive journal. "Helicobacter pylori" ranked highest in the keyword occurrences. 16S rRNA gene sequencing was the most frequently used method for microbiota analysis. Fecal samples had the highest frequency of use, followed by gastric mucosa and saliva. H. pylori infection was associated with the alterations of microbiota through the digestive tract, characterized by the enrichment of Helicobacter in the stomach. Triple and quadruple therapy were the most utilized eradication regimens, and probiotics supplementation therapy has been proven to reduce side effects and restore microbial diversity.

CONCLUSIONS

This bibliometric analysis provides an overview of advancements in the field of H. pylori and microbiota. While numerous studies have been conducted on the correlation between H. pylori and the alterations of microbiota, future research is warranted to investigate the mechanisms underlying the interplay between H. pylori and other microbes in the development of related diseases.

Crosstalk between Helicobacter pylori and gastrointestinal microbiota in various gastroduodenal diseases-A systematic review

Gastroduodenal diseases have prevailed for a long time and more so due to dominance of gut bacteria Helicobacter pylori in most of the cases. But habitation by other gut microbiota in gastroduodenal diseases and the relationship between Helicobacter pylori and gastrointestinal microbiota in different gastroduodenal diseases is somewhat being unravelled in the current times. For this systematic review, we did a literature search of various gastroduodenal diseases and the effect on gut microbiota pertaining to it. A search of the online bibliographic databases PUBMED and PUBMED CENTRAL was carried out to identify articles published between 1977 and May 2022. The analysis of these selected studies highlighted the inhabitation of other gut microbiota such as Fusobacteria, Bacteroidetes, Streptococcaceae, Prevotellaceae, Fusobacteriaceae, and many others. Interplay between these microbiota and H. pylori have also been noted which suggested that gastroduodenal diseases and gut microbiota are intertwined by a symbiotic association regardless of the H. pylori status. The relationship between the gut microbiota and many gastroduodenal diseases, such as gastritis, gastric cancer, lymphomas, and ulcers, demonstrates the dysbiosis of the gut microbiota in both the presence and absence of H. pylori. The evolving ways for eliminating H. pylori are provided along with inhibiting qualities of other species on H. pylori. Most significant member of our gut system is Helicobacter pylori which has been associated with numerous diseases like gastric cancer, gastritis, duodenal ulcer.

Efficacy and safety of vonoprazan-amoxicillin dual therapy for Helicobacter pylori first-line treatment: a single-center, randomized, controlled trial

Background

With the increase in antibiotic resistance, the success rate of Helicobacter pylori (H. pylori) eradication therapy has declined in recent years. Vonoprazan-amoxicillin (VA) dual therapy has been reported to be a promising regimen.

Objectives

To compare the efficacy and safety of VA dual therapy and bismuth quadruple therapy containing amoxicillin and clarithromycin for H. pylori first-line eradication, and to further analyze the effects of clarithromycin resistance on eradication rate.

Design

This study was a single-center, open-label, randomized controlled trial.

Methods

Treatment-naïve H. pylori-infected patients were randomly allocated 1:1 to the VA group (vonoprazan 20 mg twice daily and amoxicillin 750 mg four times daily, for 14 days) or the RBAC group (rabeprazole 10 mg, bismuth potassium citrate 220 mg, amoxicillin 1000 mg and clarithromycin 500 mg twice daily, for 14 days). H. pylori clarithromycin resistance and CYP2C19 gene polymorphisms were detected with real-time polymerase chain reaction (PCR) technique. The eradication rates and adverse events were analyzed.

Results

A total of 151 patients were enrolled. The intention-to-treat (ITT), modified intention-to-treat (mITT), and per-protocol (PP) eradication rates and their 95% confidence intervals (95% CIs) were 94.6% (86.0-98.3%), 98.6% (91.3-99.9%), and 98.5% (90.9-99.9%) for VA group and 87.0% (77.0-93.3%), 91.8% (82.3-96.6%), and 93% (83.7-97.4%) for RBAC group. The eradication rate of the VA group was noninferior to the RBAC group in ITT, mITT, and PP analyses (p < 0.0001). In patients infected with strains of clarithromycin resistance point mutation, the eradication rate of the RBAC group decreased to lower than 90%, but the difference from the VA group did not achieve statistical significance (ITT eradication rate: 81.5% in the RBAC group and 96.2% in the VA group, p = 0.192). The incidence of adverse events in the VA group was 39.2%, which was significantly lower than that in the RBAC group (79.2%, p = 0.000).

Conclusion

The efficacy of VA dual therapy is noninferior to RBAC in H. pylori first-line eradication, with fewer adverse reactions.

Registration

This study was registered at the Chinese Clinical Trial Registry (ChiCTR2100052550) on 30 October 2021.

The Influence of Helicobacter pylori on Human Gastric and Gut Microbiota

Helicobacter pylori is a Gram-negative bacterium that is able to colonize the human stomach, whose high prevalence has a major impact on human health, due to its association with several gastric and extra-gastric disorders, including gastric cancer. The gastric microenvironment is deeply affected by H. pylori colonization, with consequent effects on the gastrointestinal microbiota, exerted via the regulation of various factors, including gastric acidity, host immune responses, antimicrobial peptides, and virulence factors. The eradication therapy required to treat H. pylori infection can also have detrimental consequences for the gut microbiota, leading to a decreased alpha diversity. Notably, therapy regimens integrated with probiotics have been shown to reduce the negative effects of antibiotic therapy on the gut microbiota. These eradication therapies combined with probiotics have also higher rates of eradication, when compared to standard treatments, and are associated with reduced side effects, improving the patient's compliance. In light of the deep impact of gut microbiota alterations on human health, the present article aims to provide an overview of the complex interaction between H. pylori and the gastrointestinal microbiota, focusing also on the consequences of eradication therapies and the effects of probiotic supplementation.

Dual therapy for Helicobacter pylori infection

ABSTRACT

Bismuth-containing quadruple therapy (BQT) has long been recommended for Helicobacter pylori ( H. pylori ) eradication in China. Meanwhile, in the latest national consensus in China, dual therapy (DT) comprising an acid suppressor and amoxicillin has also been recommended. In recent years, the eradication rate of H. pylori has reached >90% using DT, which has been used not only as a first-line treatment but also as a rescue treatment. Compared with BQT, DT has great potential for H. pylori eradication; however, it has some limitations. This review summarizes the development of DT and its application in H. pylori eradication. The H. pylori eradication rates of DT were comparable to or even higher than those of BQT or standard triple therapy, especially in the first-line treatment. The incidence of adverse events associated with DT was lower than that with other therapies. Furthermore, there were no significant differences in the effects of dual and quadruple therapies on gastrointestinal microecology. In the short term, H. pylori eradication causes certain fluctuations in the gastrointestinal microbiota; however, in the long term, the gastrointestinal microbiota eventually returns to its normal state. In the penicillin-naïve population, patients receiving DT have a high eradiation rate, better compliance, lower incidence of adverse reactions, and lower primary and secondary resistance to amoxicillin. These findings suggest the safety, efficacy, and potential of DT for H. pylori eradication.

Efficacy of <i>Saccharomyces boulardii</i> CNCM I-745 probiotic drug in the prevention and treatment of diarrhea in hospitalized patients with new coronavirus infection COVID-19

Aim. To evaluate the efficacy of Saccharomyces boulardii (S. boulardii) CNCM I-745 probiotic drug in preventing and treating diarrhea in hospitalized patients with COVID-19. Materials and methods. A prospective comparative study was conducted in two parallel groups. The study included males and females aged 18 to 60 with the following diagnosis confirmed by polymerase chain reaction: U07.2 Coronavirus infection COVID-19, caused by SARS-CoV-2 virus (grade 13 pneumonia according to CT scan). All patients received antibiotic therapy. The patients were subdivided into two equal groups (n=60) depending on the administration of S. boulardii CNCM I-745 probiotic drug in addition to standard treatment. The probiotic was prescribed by the attending physician; the dose was 2 capsules per day (500 mg/day) 30 min before the meal for 10 days. All patients were monitored for main clinical, laboratory, and instrumental parameters during the study. In addition, the symptom of diarrhea (stool with a frequency of more than 3 times a day of type 6 and 7 according to the Bristol stool scale), including its frequency, duration, and the number of bowel movements of loose stool per day were precisely evaluated in both groups. Results. In the overall patient pool, diarrhea was reported in 21.7% of in-patients during the observation period (95% confidence interval [CI] 14.229.1) with a mean duration of 4.6154 days (95% CI 3.7910-5.4398). The incidence of diarrhea in group 1 was 13.3% (95% CI 4.522.2), and in group 2, it was 30.0% (95% CI 18.141.9). Relative risk showed that the use of the S. boulardii CNCM I-745 probiotic drug leads to a significant reduction in the risk of diarrhea in hospitalized patients with COVID-19 infection receiving antibiotic therapy (odds ratio [OR] 0.3590, 95% CI 0.14210.9069; p=0.0303). In group 1, the duration of diarrhea was 3.1250 days (95% CI 2.58923.6608) versus 5.2778 days (95% CI 4.22906.3265) in group 2, p=0.0112. The mean daily frequency of loose stools in patients with diarrhea in group 1 was 3.2500 (95% CI 2.65883.8412) versus 4.3889 (95% CI 3.72525.0525) in group 2, p=0.0272. The secondary endpoint, duration of hospital stay, was also significantly shorter in group 1 patients 11.6833 days (95% CI 11.204212.1625) versus 12.7333 days (95% CI 12.135713.3309) in group 2, p=0.0120. Conclusion. The present prospective comparative study demonstrated that adding S. boulardii CNCM I-745 probiotic drug into the standard treatment regimen of patients with new coronavirus infection COVID-19 receiving antibiotic therapy helps reduce the incidence of diarrhea and its severity during hospitalization, as well as the duration of hospital stay.

Probiotics modulate gastrointestinal microbiota after Helicobacter pylori eradication: A multicenter randomized double-blind placebo-controlled trial

BACKGROUND

Helicobacter pylori (H. pylori) eradication has been reported to cause short-term disruption of gut microbiota. It is acknowledged that probiotics supplementation mitigates side effects induced by H. pylori eradication, yet its role on alleviating dysbiosis of microbiota is obscure.

OBJECTIVES

To evaluate the impact of probiotics on gastrointestinal microbiota after eradication therapy.

METHODS

This was a multicenter, double-blinded, randomized trial done at seven centers in China. A total of 276 treatment-naïve H. pylori-positive patients were randomly assigned to receive 14-day bismuth-containing quadruple therapy (esomeprazole, bismuth, amoxicillin, furazolidone) combined with probiotics (Bifidobacterium Tetragenous viable Bacteria Tablets) (n=140) or placebo (n=136) for 28 days. Saliva, gastric mucosa and fecal samples were collected before and after therapy for 16S rRNA gene sequencing.

RESULTS

The incidence of gastrointestinal adverse events was lower in probiotics group compared to placebo group (23.6% vs 37.7%, p=0.016), while there was no significant difference in eradication rate. We found dramatic perturbations of gut microbiota immediately following eradication, with the predominance of Proteobacteria in replacement of commensal Firmicutes and Bacteroidetes, and gradually restored after two weeks. The reduction of gut Bacteroidetes caused by eradication drugs was neutralized with probiotics supplementation. The gastric microbiota was completely reconstituted with H. pylori depleted and other taxa flourished. Of note, patients treated with probiotics showed smaller fluctuations of gastric microbiota compared to those with placebo. We also observed changes of saliva microbiota after H. pylori eradication, illustrated by the overgrowth of Neisseria and depletion of Streptococcus. The expansion of some pathogenic genera, including Porphyromonas, Leptotrichia, in the mouth was suppressed by probiotics.

CONCLUSION

This study not only demonstrated the beneficial effect of probiotics implementation on side events during H. pylori eradication but also provided a comprehensive profile of microbiome alterations along gastrointestinal tract that modulated by probiotics.

Effects of Helicobacter pylori Therapy on Gut Microbiota: A Systematic Review and Meta-Analysis

BACKGROUND

Although indications for evaluation and treatment of Helicobacter pylori infection are broadening to include primary prevention for gastric adenocarcinoma, potential adverse effects on gut microbiota have been raised. We performed a systematic review and meta-analysis to evaluate the effects of H. pylori therapy on gut microbiota.

METHODS

PubMed, EMBASE, Cochrane Library, and Web of Science (to 4/2021) were searched for studies quantitatively evaluating microbiota before and after H. pylori therapy. Meta-analysis was performed to assess early (<1 year) and long-term (≥1 year) effects on gut microbiota after H. pylori treatment. Subgroup analysis evaluating the effects of H. pylori therapy with addition of probiotics on gut microbiota was also performed.

RESULTS

Thirty studies (N = 1,218) met the criteria. Early after H. pylori therapy, intestinal microbial diversity was reduced in nearly all studies. At the genus level, reduction in the abundance of Enterococcus, while increase in Lactobacillus, Bifidobacterium, and Bacteroides counts were observed. However, Enterococcus, Lactobacillus, Bifidobacterium, and Bacteroides counts remained stable in patients who received probiotics with H. pylori therapy. At the phylum level, the relative abundance of Actinobacteria and Firmicutes increased after treatment. At ≥1 year, intestinal microbial diversity normalized in six of seven studies. No differences in the relative abundance of Actinobacteria, Firmicute, Bacteroidetes, and Proteobacteria were observed ≥1 year after therapy.

CONCLUSION

The impact of H. pylori therapy on gut microbiota appears transient with early changes largely resolving after 1 year. Probiotics may reduce the early impact of H. pylori therapy on gut microbiota.

Analysis of oral microbiota alterations induced by Helicobacter pylori infection and vonoprazan-amoxicillin dual therapy for Helicobacter pylori eradication

BACKGROUND

The oral cavity is considered a potential reservoir of Helicobacter pylori (H. pylori), and the imbalance of oral microbiota directly reflects the health of the host. We aimed to explore the relationship among oral microbiota, H. pylori infection, and vonoprazan-amoxicillin (VA) dual therapy for H. pylori eradication.

METHODS

Helicobacter pylori-positive patients were randomized into low- or high-dose VA dual therapy (i.e., amoxicillin 1 g b.i.d. or t.i.d. and vonoprazan 20 mg b.i.d) for 7 or 10 days. H. pylori-negative patients served as normal controls. Saliva samples were collected from 41 H. pylori-positive patients and 13 H. pylori-negative patients. The oral microbiota was analyzed by 16S rRNA gene sequencing, followed by bioinformatics analysis.

RESULTS

Helicobacter pylori-positive patients had higher richness and diversity and better evenness of oral microbiota than normal controls. Beta diversity analysis estimated by Bray-Curtis or weighted UniFrac showed distinct clustering between H. pylori-positive patients and normal controls. The number of bacterial interactions was reduced in H. pylori-positive patients compared with that in negative patients. Forty-one patients evaluated before and after successful H. pylori eradication were divided into low (L-VA) and high dose (H-VA) amoxicillin dose groups. The alpha and beta diversity of the oral microbiota between L-VA and H-VA patients exhibited no differences at the three time points (before eradication, after eradication, and at confirmation of H. pylori infection cure).

CONCLUSION

Helicobacter pylori infection could alter the diversity, composition, and bacterial interactions of the oral microbiota. Both L-VA and H-VA dual therapy showed minimal influence on the oral microbiota.

Gut Microbiota Dysbiosis in the Development and Progression of Gastric Cancer

Objectives

This study aims to explore gut microbiota dysbiosis in the histological stages of gastric cancer (GC).

Methods

Feces samples and clinical characteristics were collected from patients with different stages of GC, including 15 superficial gastritis (SG), 13 atrophic gastritis (AG), 8 gastric mucosal atypical hyperplasia (GMAH), and 15 advanced GC cases. The diversity and composition of gut microbiota among the four groups were determined by sequencing the V4 region of bacterial 16S rRNA genes.

Results

Reduced gut microbial alpha diversity and altered dissimilarity of the microbial community structure were found among the four groups. In addition, 18 species, 6 species, 6 species, and 16 species of bacteria were enriched in the SG, AG, GMAH, and GC groups, respectively, using the linear discriminant analysis (LDA) effect size (LEfSe) analyses. Besides, we found that two new genera, Scardovia and Halomonas, are associated with GC and the metabolic pathways of Genetic information processing and Circulatory System were more abundant in the GC group compared with noncancer groups.

Conclusions

We identified differences in microbial compositional changes across stages of GC. Six genera and two metabolic pathways were more abundant in the GC group than noncancer groups, suggesting that these findings may contribute to the therapy strategies in GC in the near feature.

The double-edged sword of probiotic supplementation on gut microbiota structure in Helicobacter pylori management

As Helicobacter pylori management has become more challenging and less efficient over the last decade, the interest in innovative interventions is growing by the day. Probiotic co-supplementation to antibiotic therapies is reported in several studies, presenting a moderate reduction in drug-related side effects and a promotion in positive treatment outcomes. However, the significance of gut microbiota involvement in the competence of probiotic co-supplementation is emphasized by a few researchers, indicating the alteration in the host gastrointestinal microbiota following probiotic and drug uptake. Due to the lack of long-term follow-up studies to determine the efficiency of probiotic intervention in H. pylori eradication, and the delicate interaction of the gut microbiota with the host wellness, this review aims to discuss the gut microbiota alteration by probiotic co-supplementation in H. pylori management to predict the comprehensive effectiveness of probiotic oral administration.Abbreviations: acyl-CoA- acyl-coenzyme A; AMP- antimicrobial peptide; AMPK- AMP-activated protein kinase; AP-1- activator protein 1; BA- bile acid; BAR- bile acid receptor; BCAA- branched-chain amino acid; C2- acetate; C3- propionate; C4- butyrate; C5- valeric acid; CagA- Cytotoxin-associated gene A; cAMP- cyclic adenosine monophosphate; CD- Crohn's disease; CDI- C. difficile infection; COX-2- cyclooxygenase-2; DC- dendritic cell; EMT- epithelial-mesenchymal transition; FMO- flavin monooxygenases; FXR- farnesoid X receptor; GPBAR1- G-protein-coupled bile acid receptor 1; GPR4- G protein-coupled receptor 4; H2O2- hydrogen peroxide; HCC- hepatocellular carcinoma; HSC- hepatic stellate cell; IBD- inflammatory bowel disease; IBS- irritable bowel syndrome; IFN-γ- interferon-gamma; IgA immunoglobulin A; IL- interleukin; iNOS- induced nitric oxide synthase; JAK1- janus kinase 1; JAM-A- junctional adhesion molecule A; LAB- lactic acid bacteria; LPS- lipopolysaccharide; MALT- mucosa-associated lymphoid tissue; MAMP- microbe-associated molecular pattern; MCP-1- monocyte chemoattractant protein-1; MDR- multiple drug resistance; mTOR- mammalian target of rapamycin; MUC- mucin; NAFLD- nonalcoholic fatty liver disease; NF-κB- nuclear factor kappa B; NK- natural killer; NLRP3- NLR family pyrin domain containing 3; NOC- N-nitroso compounds; NOD- nucleotide-binding oligomerization domain; PICRUSt- phylogenetic investigation of communities by reconstruction of unobserved states; PRR- pattern recognition receptor; RA- retinoic acid; RNS- reactive nitrogen species; ROS- reactive oxygen species; rRNA- ribosomal RNA; SCFA- short-chain fatty acids; SDR- single drug resistance; SIgA- secretory immunoglobulin A; STAT3- signal transducer and activator of transcription 3; T1D- type 1 diabetes; T2D- type 2 diabetes; Th17- T helper 17; TLR- toll-like receptor; TMAO- trimethylamine N-oxide; TML- trimethyllysine; TNF-α- tumor necrosis factor-alpha; Tr1- type 1 regulatory T cell; Treg- regulatory T cell; UC- ulcerative colitis; VacA- Vacuolating toxin A.

Altered Gut Microbiota and Short-Chain Fatty Acids After Vonoprazan-Amoxicillin Dual Therapy for Helicobacter pylori Eradication

The combination of vonoprazan (VPZ) and amoxicillin (VA therapy) has been shown to achieve acceptable eradication rates for Helicobacter pylori (H. pylori). Herein, our aim was to explore the short-term effect of VA therapy on the gut microbiota and short-chain fatty acids (SCFAs) using human fecal samples. A total of 119 H. pylori-positive patients were randomized into low- or high-dose VA therapy (i.e., amoxicillin 1 g b.i.d. or t.i.d. and VPZ 20 mg b.i.d.) for 7 or 10 days. Thirteen H. pylori-negative patients served as controls. Fecal samples were collected from H. pylori-positive and H. pylori-negative patients. The gut microbiota and SCFAs were analyzed using 16S rRNA gene sequencing and gas chromatography–mass spectrometry, respectively. The gut microbiota in H. pylori-positive patients exhibited increased richness, diversity, and better evenness than matched patients. Fifty-three patients studied before and after H. pylori eradication were divided into low (L-VA) and high (H-VA) amoxicillin dose groups. The diversity and composition of the gut microbiota among L-VA patients exhibited no differences at the three time points. However, among H-VA patients, diversity was decreased, and the microbial composition was altered immediately after H-VA eradication but was restored by the confirmation time point. The decreased abundance of Anaerostipes, Dialister, and Lachnospira induced by H-VA was associated with altered SCFA levels. VA dual therapy for H. pylori eradication has minimal negative effects on gut microbiota and SCFAs.

Effect of Helicobacter Pylori Eradication on Human Gastric Microbiota: A Systematic Review and Meta-Analysis

Background

Helicobacter pylori (H. pylori) infection is a major risk factor for gastric cancer and eradication of H. pylori is recommended as an effective gastric cancer prevention strategy. The infected individuals show microbial dysbiosis of gastric microbiota. In recent years, agrowing number of studies have focused on gastric microbiota changes following H. pylori eradication. In the present study, we aim to evaluate the influence of successful H. pylori eradication on the short-term and long-term alterations of human gastric microbiota using a method of systematic review and meta-analysis.

Methods

We did a systematic search based on three databases (PubMed, EMBASE, and Web of Science) in November 2021. Additional articles were also identified by reviewing references cited in the included papers. Human studies that reported changes in gastric microbiota following successful H. pylori eradication were enrolled. PROSPERO registration number: CRD42021293796.

Results

In total, nine studies enrolling 546 participants were included. Regarding quadruple therapy, alpha diversity indexes increased within 1 month after eradication; significant differences in gastric microbial community structure between before and after eradication were also seen within 1 month. The trends of the above-mentioned diversity changes persisted with a follow-up of 6 months. The microbial composition altered significantly after eradication and the relative abundance of H. pylori-related taxa decreased. Accordingly, gastric commonly dominant commensals were enriched. Bioinformatic analyses of microbiota functions showed that bacteria reproduction-related pathways were down-regulated and pathways of gastric acid secretion, etc. were up-regulated. For triple therapy, similar trends of alpha diversity and beta diversity changes were observed in the short-term and long-term follow-up. Also, after eradication, H. pylori was not the gastric dominant bacteria and similar changes in gastric microbial composition were found. For gastric microbial interactions, a decrease in microbial interactions was seen after eradication. Additionally, regarding whether successful H. pylori eradication could restore gastric microbiota to uninfected status, the results remain controversial.

Conclusion

In conclusion, successful H. pylori eradication could reverse the gastric microbiota dysbiosis and show beneficial effects on gastric microbiota. Our findings may provide new insight for exploring the role of H. pylori and the whole gastric microbiota in gastric carcinogenesis.

Helicobacter pylori may participate in the development of inflammatory bowel disease by modulating the intestinal microbiota

Inflammatory bowel disease (IBD) is a non-specific inflammatory disease of the gastrointestinal (GI) tract that is generally accepted to be closely related to intestinal dysbiosis in the host. GI infections contribute a key role in the pathogenesis of IBD; however, although the results of recent clinical studies have revealed an inverse correlation between Helicobacter pylori (H. pylori) infection and IBD, the exact mechanism underlying the development of IBD remains unclear. H. pylori, as a star microorganism, has been a focus for decades, and recent preclinical and real-world studies have demonstrated that H. pylori not only affects the changes in the gastric microbiota and microenvironment but also influences the intestinal microbiota, indicating a potential correlation with IBD. Detailed analysis revealed that H. pylori infection increased the diversity of the intestinal microbiota, reduced the abundance of Bacteroidetes, augmented the abundance of Firmicutes, and produced short-chain fatty acid-producing bacteria such as Akkermansia. All these factors may decrease vulnerability to IBD. Further studies investigating the H. pylori-intestinal microbiota metabolite axis should be performed to understand the mechanism underlying the development of IBD.

Transcriptome Analysis of the Response of Mature Helicobacter pylori Biofilm to Different Doses of Lactobacillus salivarius LN12 with Amoxicillin and Clarithromycin

Helicobacter pylori is a gastrointestinal pathogen with a high infection rate. Probiotics are clinically used as an adjuvant to improve the cure rate and reduce the side effects of antibiotic treatment for H. pylori. This study is the first to explore the effects of a cell-free supernatant of high- or low-dose Lactobacillus salivarius LN12 combined with amoxicillin (AMX) and clarithromycin (CLR) on H. pylori 3192 biofilms in terms of the biofilm biomass, survival rates, biofilm structure, and transcriptome. The results showed that the combination of the CFS of high-dose LN12 with AMX and CLR had stronger effects on the biofilm biomass, survival rate, and structure of H. pylori 3192 biofilms. H. pylori 3192 biofilms may increase the expression of NADH-related genes and downregulate flagellar assembly and quorum sensing-related receptor genes to deal with the stronger stress effects of high-dose LN12 with AMX and CLR. In conclusion, the biofilm biomass, survival rate, structure, and transcriptome results showed that the combination of LN12 CFS with AMX and CLR had dose effects. We recommend that compared with low doses, high doses of L. salivarus LN12 combined with AMX and CLR may be more effective for H. pylori biofilm than low doses.

Probiotics as the live microscopic fighters against Helicobacter pylori gastric infections

Background

Helicobacter pylori (H. pylori) is the causative agent of stomach diseases such as duodenal ulcer and gastric cancer, in this regard incomplete eradication of this bacterium has become to a serious concern. Probiotics are a group of the beneficial bacteria which increase the cure rate of H. pylori infections through various mechanisms such as competitive inhibition, co-aggregation ability, enhancing mucus production, production of bacteriocins, and modulating immune response.

Result

In this study, according to the received articles, the anti-H. pylori activities of probiotics were reviewed. Based on studies, administration of standard antibiotic therapy combined with probiotics plays an important role in the effective treatment of H. pylori infection. According to the literature, Lactobacillus casei, Lactobacillus reuteri, Lactobacillus rhamnosus GG, and Saccharomyces boulardii can effectively eradicate H. pylori infection. Our results showed that in addition to decrease gastrointestinal symptoms, probiotics can reduce the side effects of antibiotics (especially diarrhea) by altering the intestinal microbiome.

Conclusion

Nevertheless, antagonist activities of probiotics are H. pylori strain-specific. In general, these bacteria can be used for therapeutic purposes such as adjuvant therapy, drug-delivery system, as well as enhancing immune system against H. pylori infection.

Impact of Helicobacter pylori infection on gut microbiota

A number of studies have revealed the association between Helicobacter pylori (H. pylori) infection and the gut microbiota. More than half of the investigations on the impact of H. pylori on the gut microbiota have been the sub-analyses of the influence of eradication therapy. It was observed that H. pylori eradication altered gut microbiota within a short period after eradication, and majority of the alterations took a long period of time to reverse back to the original. Changes in the gut microbiota within a short period after eradication may be attributed to antibiotics and proton pump inhibitors. Modification of gastric acidity in the stomach caused by a long-term H. pylori infection alters the gut microbiota. Analysis of the gut microbiota should be conducted in a large population, adjusting for considerable biases associated with the composition of the gut microbiota, such as age, sex, body mass index, diet and the virulence of H. pylori.

A Randomised, Controlled Trial: Effect of a Multi-Strain Fermented Milk on the Gut Microbiota Recovery after Helicobacter pylori Therapy

Helicobacter pylori (Hp) eradication therapy alters gut microbiota, provoking gastrointestinal (GI) symptoms that could be improved by probiotics. The study aim was to assess the effect in Hp patients of a Test fermented milk containing yogurt and Lacticaseibacillus (L. paracasei CNCM I-1518 and I-3689, L. rhamnosus CNCM I-3690) strains on antibiotic associated diarrhea (AAD) (primary aim), GI-symptoms, gut microbiota, and metabolites. A randomised, double-blind, controlled trial was performed on 136 adults under 14-day Hp treatment, receiving the Test or Control product for 28 days. AAD and GI-symptoms were reported and feces analysed for relative and quantitative gut microbiome composition, short chain fatty acids (SCFA), and calprotectin concentrations, and viability of ingested strains. No effect of Test product was observed on AAD or GI-symptoms. Hp treatment induced a significant alteration in bacterial and fungal composition, a decrease of bacterial count and alpha-diversity, an increase of Candida and calprotectin, and a decrease of SCFA concentrations. Following Hp treatment, in the Test as compared to Control group, intra-subject beta-diversity distance from baseline was lower (p_adj = 0.02), some Enterobacteriaceae, including Escherichia-Shigella (p_adj = 0.0082) and Klebsiella (p_adj = 0.013), were less abundant, and concentrations of major SCFA (p = 0.035) and valerate (p = 0.045) were higher. Viable Lacticaseibacillus strains were detected during product consumption in feces. Results suggest that, in patients under Hp treatment, the consumption of a multi-strain fermented milk can induce a modest but significant faster recovery of the microbiota composition (beta-diversity) and of SCFA production and limit the increase of potentially pathogenic bacteria.

Rejuvenation of Helicobacter pylori-Associated Atrophic Gastritis Through Concerted Actions of Placenta-Derived Mesenchymal Stem Cells Prevented Gastric Cancer

Chronic Helicobacter pylori infection causes gastric cancer via the progression of precancerous chronic atrophic gastritis (CAG). Therefore, repairing gastric atrophy could be a useful strategy in preventing H. pylori-associated gastric carcinogenesis. Although eradication of the bacterial pathogen offers one solution to this association, this study was designed to evaluate an alternative approach using mesenchymal stem cells to treat CAG and prevent carcinogenesis. Here, we used human placenta-derived mesenchymal stem cells (PD-MSCs) and their conditioned medium (CM) to treat H. pylori-associated CAG in a mice/cell model to explore their therapeutic effects and elucidate their molecular mechanisms. We compared the changes in the fecal microbiomes in response to PD-MSC treatments, and chronic H. pylori-infected mice were given ten treatments with PD-MSCs before being sacrificed for end point assays at around 36 weeks of age. These animals presented with significant reductions in the mean body weights of the control group, which were eradicated following PD-MSC treatment (p < 0.01). Significant changes in various pathological parameters including inflammation, gastric atrophy, erosions/ulcers, and dysplastic changes were noted in the control group (p < 0.01), but these were all significantly reduced in the PD-MSC/CM-treated groups. Lgr5+, Ki-67, H⁺/K⁺-ATPase, and Musashi-1 expressions were all significantly increased in the treated animals, while inflammatory mediators, MMP, and apoptotic executors were significantly decreased in the PD-MSC group compared to the control group (p < 0.001). Our model showed that H. pylori-initiated, high-salt diet-promoted gastric atrophic gastritis resulted in significant changes in the fecal microbiome at the phylum/genus level and that PD-MSC/CM interventions facilitated a return to more normal microbial communities. In conclusion, administration of PD-MSCs or their conditioned medium may present a novel rejuvenating agent in preventing the progression of H. pylori-associated premalignant lesions.

The Effect of Helicobacter pylori Eradication on Lipid Levels: A Meta-Analysis

Introduction:Helicobacter pylori (H. pylori) infection is positively associated with cardiovascular diseases, but the involvement of lipids in this association remains unclear. The present study reviewed the changes in circulating lipid levels following H. pylori eradication. Methods: A PubMed database was searched until December 2020 to identify randomized control trials (RCTs) and non-RCTs investigating the effect of H. pylori eradication on the lipid levels in inverse variance-weighted, random-effects meta-analyses. Results: A total of 24 studies (four RCTs and 20 non-RCTs) with 5270 participants were identified. The post-eradication levels were increased for high-density lipoprotein cholesterol (HDL-C; mean difference (MD) 2.28 mg/dL, 95% confidence interval (CI) 1.90 to 2.66) and triglyceride (TG; MD 3.22 mg/dL, 95% CI 1.13 to 5.31) compared with the pre-eradication levels. H. pylori eradication resulted in little to no difference in the low-density lipoprotein-cholesterol levels (MD −2.33 mg/dL, 95% CI −4.92 to 0.26). In the analyses of RCTs only, the findings for elevated HDL-C levels, but not TG, were robust. Conclusions:H. pylori eradication increases the HDL-C levels. Further studies are needed to elucidate the effects of lipid changes following H. pylori eradication on cardiovascular diseases.

[Efficacy of butyric acid inclusion in eradication regimens for Helicobacter pylori infection: a meta-analysis of controlled trials]

AIM

Systematization of data on the efficacy and safety of butyric acid inclusion in eradication therapy (ET) regimens for Helicobacter pylori infection.

METHODS

Research searches were carried out in the electronic databases MEDLINE/PubMed, EMBASE, Cochrane, Google Scholar, the Russian Science Citation Index (RSCI) until November 2020. All controlled studies comparing the efficacy and/or safety of including butyric acid in ET regimens for H. pylori infection were included in the final analysis.

RESULTS

The meta-analysis included 6 controlled studies (1 Italy, 5 Russia) involving 736 patients (381 in the ET groups with butyric acid; 355 in the comparison groups). The pooled eradication efficiency in the butyric acid groups was 90.23% (95% confidence interval CI 86.73493.069), while in the comparison groups it was 65.69% (95% CI 60.44170.669). Meta-analysis showed that the addition of butyric acid to ET regimens significantly increased the eradication efficiency (odds ratio OR 5.355, 95% CI 3.5048.184; p0.001). There was no significant heterogeneity between results (p=0.1408; I2=42.1%). The addition of butyric acid to ET regimens significantly reduces the risk of diarrhea (OR 0.225, 95% CI 0.09230.549; p=0.001; I2=34.21%) and abdominal distention (OR 0.357, 95% CI 0.1550.818; p=0.015; I2=80.13%) by the end of the 1st week of treatment.

CONCLUSION

The present meta-analysis demonstrated that the inclusion of butyric acid in ET regimens for H. pylori infection significantly increases the effectiveness of treatment and reduce the incidence of side effects. Apparently, the increase in the effectiveness of eradication is due to an increase in patient compliance with treatment due to an improvement in the safety profile of therapy.

Gut microbiota changes related to Helicobacter pylori eradication with vonoprazan containing triple therapy among adolescents: a prospective multicenter study

Currently, it is unclear whether treating Helicobacter pylori (H. pylori) infection is safe among adolescents. This study aimed to evaluate the safety of H. pylori eradication therapy by examining gut microbiota changes in adolescents 3 months after the therapy. H. pylori-infected adolescents were enrolled in this study. Their stool samples were collected at the following three time points: before treatment, 1-2 days after completion of treatment, and time of eradication successful judgment. We assessed the relative abundance, alpha-diversity, and beta-diversity of the gut microbiota and adverse events. The number of isolated Actinobacteria decreased immediately after eradication therapy in the 16 students included in the study, and it returned to pretreatment condition at the eradication judgment point. There was no change in the relative abundance at genus level. The alpha-diversity was lost immediately after eradication therapy; however, it recovered at the time of eradication judgment, and it was restored to pretreatment condition. Meanwhile, none of the participants experienced serious adverse events. H. pylori eradication therapy is safe for adolescents with respect to gut microbiota changes associated with H. pylori eradication therapy. Therefore, further long-term evaluations of gut microbiota changes following eradication therapy are warranted.

Gut Microbiota: The Missing Link Between Helicobacter pylori Infection and Metabolic Disorders?

Helicobacter pylori (H. pylori) is a gram-negative bacterium that infects approximately 4.4 billion individuals worldwide. Although the majority of infected individuals remain asymptomatic, this bacterium colonizes the gastric mucosa causing the development of various clinical conditions as peptic ulcers, chronic gastritis and gastric adenocarcinomas and mucosa-associated lymphoid tissue lymphomas, but complications are not limited to gastric ones. Extradigestive pathologies, including metabolic disturbances such as diabetes, obesity and nonalcoholic fatty liver disease, have also been associated with H. pylori infection. However, the underlying mechanisms connecting H. pylori with extragastric metabolic diseases needs to be clarified. Notably, the latest studies on the topic have confirmed that H. pylori infection modulates gut microbiota in humans. Damage in the gut bacterial community (dysbiosis) has been widely related to metabolic dysregulation by affecting adiposity, host energy balance, carbohydrate metabolism, and hormonal modulation, among others. Taking into account that Type 2 diabetic patients are more prone to be H. pylori positive, gut microbiota emerges as putative key factor responsible for this interaction. In this regard, the therapy of choice for H. pylori eradication, based on proton pump inhibitor combined with two or more antibiotics, also alters gut microbiota composition, but consequences on metabolic health of the patients has been scarcely explored. Recent studies from our group showed that, despite decreasing gut bacterial diversity, conventional H. pylori eradication therapy is related to positive changes in glucose and lipid profiles. The mechanistic insights explaining these effects should also be addressed in future research. This review will deal with the role of gut microbiota as the linking factor between H. pylori infection and metabolic diseases, and discussed the impact that gut bacterial modulation by H. pylori eradication treatment can also have in host's metabolism. For this purpose, new evidence from the latest human studies published in more recent years will be analyzed.

The interplay between Helicobacter pylori and gastrointestinal microbiota

The complex population of microbes in the human gastrointestinal (GI) tract interacts with itself and with the host, exerting a deep influence on health and disease development. The development of modern sequencing technology has enabled us to gain insight into GI microbes. Helicobacter pylori colonization significantly affects the gastric microenvironment, which in turn affects gastric microbiota and may be correlated with colonic microbiota changes. Crosstalk between H. pylori and GI commensal flora may play a role in H. pylori-related carcinogenicity and extragastric manifestations. We review current knowledge on how H. pylori shapes GI microbiota with a specific focus on its impact on the stomach and colon. We also review current evidence on colonic microbiota changes attributed to eradication therapy based on the clinical studies performed to date.