The Effect of Probiotics Supplementation on Gut Microbiota After Helicobacter pylori Eradication: A Multicenter Randomized Controlled Trial.Infect Dis Ther. 2021;10:317-333. [PMID: 33270205 DOI: 10.1007/s40121-020-00372-9]

Long-term effects of fecal microbiota transplantation on gut microbiota after Helicobacter pylori eradication with bismuth quadruple therapy: A randomized controlled trial

BACKGROUND

Eradicating Helicobacter pylori infection by bismuth quadruple therapy (BQT) is effective. However, the effect of BQT and subsequent fecal microbiota transplant (FMT) on the gut microbiota is less known.

MATERIALS AND METHODS

This prospective randomized controlled trial was conducted at a tertiary hospital in China from January 2019 to October 2020, with the primary endpoints the effect of BQT on the gut microbiota and the effect of FMT on the gut microbiota after bismuth quadruple therapy eradication therapy. A 14-day BQT with amoxicillin and clarithromycin was administered to H. pylori-positive subjects, and after eradication therapy, patients received a one-time FMT or placebo treatment. We then collected stool samples to assess the effects of 14-day BQT and FMT on the gut microbiota. 16 s rDNA and metagenomic sequencing were used to analyze the structure and function of intestinal flora. We also used Gastrointestinal Symptom Rating Scale (GSRS) to evaluate gastrointestinal symptom during treatment.

RESULTS

A total of 30 patients were recruited and 15 were assigned to either FMT or placebo groups. After eradication therapy, alpha-diversity was decreased in both groups. At the phylum level, the abundance of Bacteroidetes and Firmicutes decreased, while Proteobacteria increased. At the genus level, the abundance of beneficial bacteria decreased, while pathogenic bacteria increased. Eradication therapy reduced some resistance genes abundance while increased the resistance genes abundance linked to Escherichia coli. While they all returned to baseline by Week 10. Besides, the difference was observed in Week 10 by the diarrhea score between two groups. Compared to Week 2, the GSRS total score and diarrhea score decreased in Week 3 only in FMT group.

CONCLUSIONS

The balance of intestinal flora in patients can be considerably impacted by BQT in the short term, but it has reverted back to baseline by Week 10. FMT can alleviate gastrointestinal symptoms even if there was no evidence it promoted restoration of intestinal flora.

Role of probiotic as adjuvant in treating various infections: a systematic review and meta-analysis

BACKGROUND

Research on the advantages of probiotics has attracted increasing interest based on the number of publications, products, and public awareness of their benefits. This review evaluated the role of probiotics (single and multiple regimens) as an additional regimen to treat common infectious diseases, including Helicobacter. pylori, diarrheal infections, urinary tract infections (UTIs), upper respiratory tract infections (URTIs), and HIV infections.

METHODS

We searched randomized controlled trials from PubMed, Scopus, Embase, and Cochrane and identified 6,950 studies. Duplicates were removed, and titles and abstracts were filtered. Bias was evaluated using the Cochrane Risk of Bias Tool for Randomized Trials (ROB 1.0 and 2.0). The certainty of the evidence was evaluated using GRADE. Data were extracted and meta-analysis was performed using RevMan.

RESULTS

A total of 32 studies were included in this study (22 H. pylori studies, 2 diarrheal infection studies, 6 UTI studies, and 2 HIV infection studies). There was no study on URTI. Probiotics, in addition to primary treatment, could improve the eradication of H. pylori versus the control (RR: 1.09; 95% CI:1.04 - 1.13, p value = 0.001) and achieve a cure range of Nugent score in UTI patients (RR 1.38; 95% CI: 1.01 - 1.89, p value = 0.04). For eradicating H. pylori infection, subgroup analysis based on the therapy regimen showed that standard triple therapy was slightly superior compared to quadruple therapy in eradicating H. pylori (RR: 1.14 vs. 1.01, respectively). Single strain probiotics showed a similar effect to multiple strain probiotic regimens (both had an RR of 1.09). The effect estimates of the use of single strain probiotics as adjuvant therapy in eradicating H. pylori and the use of probiotics in UTI had a high certainty of evidence. Meta-analysis was not performed for infectious diarrheal because there were only two eligible studies with different probiotic supplementations and outcome parameters. Nonetheless, they showed that the diarrheal incidence was lower and complete remission of diarrheal was higher after the regimen of probiotics. Similarly, a meta-analysis was not performed for HIV infection because the two eligible studies used different designs and comparators with contradicting findings.

CONCLUSION

This meta-analysis showed beneficial use of single strain probiotics as adjuvant therapy in eradicating H. pylori and the use of probiotics in UTI. Probiotic supplementation might not be beneficial for patients given a quadruple therapy. Single-strain and multi-strain probiotic regimens had similar effects in increasing the eradication rate of H. pylori. Our study also suggested that the benefits of probiotics as an additional regimen in infectious diarrheal and HIV infections remain unclear; more studies are needed to confirm the benefits.

The Role of Probiotics in the Eradication of Helicobacter pylori and Overall Impact on Management of Peptic Ulcer: A Study Involving Patients Undergoing Triple Therapy in Bangladesh

Background Helicobacter pylori infection has been identified to cause constantly recurring inflammation, leading to gastrointestinal tract disorders, including carcinoma. The standard triple therapy (STT), used to eradicate H. pylori, includes two antimicrobials and a proton pump inhibitor for two weeks. Other drug regimens have also been developed since H. pylori exhibits antimicrobial resistance. These regimens, including probiotics, have been shown to lower adverse drug reactions (ADR), improve drug adherence, exert bacteriostatic effect, and reduce inflammation. Objective This study intended to explore probiotic intervention for improving eradication rates and mitigating adverse effects while administrating STT.  Methods This prospective study was conducted from May to December, 2021, in the Department of Gastroenterology of Ship International Hospital, Dhaka, Bangladesh, to observe the effects of probiotics inclusion along with STT on H. pylori eradication. A total of 100 patients aged ≥18 years who tested positive for H. pylori were included. The experimental group (n=50) was given STT and probiotics, and the control group (n=50) was given only STT without probiotics for 14 days. Necessary follow-up was done six weeks after treatment. An independent sample t-test, chi-square test, and multiple regression analysis were used for statistical analysis. Result The odds of getting rapid urease test (RUT) negative results from positive were 2.06 times higher (95%CI= 0.95, 3.22, p=0.054) in the experimental group. ADRs were crucially towering in the control group (p=0.045) compared to the probiotics group. The probiotics group had a lower risk of having adverse effects by 0.54 times (95%CI=0.19, 0.84, p=0.032) than the control group. Conclusion Using probiotics and STT together to eradicate H. pylori may lower ADR and improve treatment adherence. It may also help terminate H. pylori infection more effectively. More research is required as H. pylori is very contagious and can ultimately cause life-threatening gastric cancer.

Butyric Acid Supplementation Reduces Changes in the Taxonomic and Functional Composition of Gut Microbiota Caused by H. pylori Eradication Therapy

H. pylori eradication therapy leads to significant changes in the gut microbiome, including influence on the gut microbiome's functional potential. Probiotics are one of the most studied potential methods for reducing the microbiota-related consequences of antibiotics. However, the beneficial effects of probiotics are still under discussion. In addition, there are some concerns about the safety of probiotics, emphasizing the need for research of other therapeutic interventions. The aim of our study was to evaluate the influence of butyric acid+inulin supplements on gut microbiota changes (the gut microbiota composition, abundance of metabolic pathways, and gut resistome) caused by H. pylori eradication therapy.

MATERIALS AND METHODS

Twenty two H. pylori-positive patients, aged 19 to 64 years, were enrolled in the study and randomized into two treatment groups, as follows: (1) ECAB-14 (n = 11), with esomeprazole 20 mg, clarithromycin 500 mg, amoxicillin 1000 mg, and bismuthate tripotassium dicitrate 240 mg, twice daily, per os, for 14 days, and (2), ECAB-Z-14 (n = 11), with esomeprazole 20 mg, clarithromycin 500 mg, amoxicillin 1000 mg, and bismuthate tripotassium dicitrate 240 mg, twice daily, along with butyric acid+inulin (Zacofalk), two tablets daily, each containing 250 mg of butyric acid, and 250 mg of inulin, per os, for 14 days. Fecal samples were collected from each subject prior to eradication therapy (time point I), after the end of eradication therapy (time point II), and a month after the end of eradication therapy (time point III). The total DNA from the fecal samples was isolated for whole genome sequencing using the Illumina NextSeq 500 platform. Qualitative and quantitative changes in gut microbiota were assessed, including alpha and beta diversity, functional potential and antibiotic resistance gene profiling.

RESULTS

Gut microbiota alpha diversity significantly decreased compared with the baseline immediately after eradication therapy in both treatment groups (ECAB-14 and ECAB-Z-14). This diversity reached its baseline in the ECAB-Z-14 treatment group a month after the end of eradication therapy. However, in the ECAB-14 treatment arm, a reduction in the Shannon index was observed up to a month after the end of H. pylori eradication therapy. Fewer alterations in the gut microbiota functional potential were observed in the ECAB-Z-14 treatment group. The abundance of genes responsible for the metabolic pathway associated with butyrate production decreased only in the ECAB-14 treatment group. The prevalence of antibiotic-resistant genes in the gut microbiota increased significantly in both treatment groups by the end of treatment. However, more severe alterations were noted in the ECAB-14 treatment group.

CONCLUSIONS

H. pylori eradication therapy leads to taxonomic changes, a reduction in the alpha diversity index, and alterations in the functional potential of the gut microbiota and gut resistome. Taking butyric acid+inulin supplements during H. pylori eradication therapy could help maintain the gut microbiota in its initial state and facilitate its recovery after H. pylori eradication.

Effect of Lactobacillus plantarum ZFM4 in Helicobacter pylori-infected C57BL/6 mice: prevention is better than cure

Objectives

This study was performed to explore the preventive and therapeutic effects of Lactobacillus plantarum ZFM4 on H. pylori infections of the stomach tissue in C57BL/6 mice.

Methods

In this study, 40 specific-pathogen-free female C57BL/6 mice were randomly divided into five groups, namely, the control, ZFM4 pretreatment) ZFM4 pretreatment before H. pylori infected), model (H. pylori infected), triple therapy (H. pylori infected and treated with triple therapy), and ZFM4 treatment groups (H. pylori infected and treated with ZFM4). The preventive and therapeutic effects of Lactobacillus plantarum ZFM4 were evaluated in H. pylori-infected C57BL/6 mice by assessing gastric tissue morphology, inflammatory cytokine levels, microbial composition, and microbial diversity.

Results

Lactobacillus plantarum ZFM4 was able to survive in low gastric pH and play a role in preventing H. pylori infection. This was evident from a reduction in both, the gastric inflammatory response and expression of inflammatory factors caused by H. pylori infection. Lactobacillus plantarum ZFM4 could also inhibit the growth of H. pylori via its beneficial impact on the gastric microbiota.

Conclusion

Our findings suggest that Lactobacillus plantarum ZFM4 offers superior preventive effects against H. pylori infections when used alone. However, the therapeutic effect on established infections is weaker. Further clinical trials are needed to confirm the specific dosage, duration, and other aspects of administration.

The use of probiotics and prebiotics in decolonizing pathogenic bacteria from the gut; a systematic review and meta-analysis of clinical outcomes

Repeated exposure to antibiotics and changes in the diet and environment shift the gut microbial diversity and composition, making the host susceptible to pathogenic infection. The emergence and ongoing spread of AMR pathogens is a challenging public health issue. Recent evidence showed that probiotics and prebiotics may play a role in decolonizing drug-resistant pathogens by enhancing the colonization resistance in the gut. This review aims to analyze available evidence from human-controlled trials to determine the effect size of probiotic interventions in decolonizing AMR pathogenic bacteria from the gut. We further studied the effects of prebiotics in human and animal studies. PubMed, Embase, Web of Science, Scopus, and CINAHL were used to collect articles. The random-effects model meta-analysis was used to pool the data. GRADE Pro and Cochrane collaboration tools were used to assess the bias and quality of evidence. Out of 1395 citations, 29 RCTs were eligible, involving 2871 subjects who underwent either probiotics or placebo treatment to decolonize AMR pathogens. The persistence of pathogenic bacteria after treatment was 22%(probiotics) and 30.8%(placebo). The pooled odds ratio was 0.59(95% CI:0.43-0.81), favoring probiotics with moderate certainty (p = 0.0001) and low heterogeneity (I2 = 49.2%, p = 0.0001). The funnel plot showed no asymmetry in the study distribution (Kendall'sTau = -1.06, p = 0.445). In subgroup, C. difficile showed the highest decolonization (82.4%) in probiotics group. Lactobacillus-based probiotics and Saccharomyces boulardii decolonize 71% and 77% of pathogens effectively. The types of probiotics (p < 0.018) and pathogens (p < 0.02) significantly moderate the outcome of decolonization, whereas the dosages and regions of the studies were insignificant (p < 0.05). Prebiotics reduced the pathogens from 30% to 80% of initial challenges. Moderate certainty of evidence suggests that probiotics and prebiotics may decolonize pathogens through modulation of gut diversity. However, more clinical outcomes are required on particular strains to confirm the decolonization of the pathogens. Protocol registration: PROSPERO (ID = CRD42021276045).

Weizmannia coagulans BCF-01: a novel gastrogenic probiotic for Helicobacter pylori infection control

The widespread prevalence of Helicobacter pylori infection, particularly in China, contributes to the development of gastrointestinal diseases. Antibiotics have limitations, including adverse reactions and increased antibiotic resistance. Therefore, identification of novel gastrogenic probiotics capable of surviving the acidic gastric environment and effectively combating H. pylori infection has potential in restoring gastric microbiota homeostasis. Five novel strains of human gastrogenic Weizmannia coagulans (BCF-01-05) were isolated from healthy gastric mucosa and characterized using 16S rDNA identification. Acid resistance, H. pylori inhibition, and adherence to gastric epithelial cells were evaluated in in-vitro experiments and the molecular mechanism explored in in-vivo experiments. Among the gastric-derived W. coagulans strains, BCF-01 exhibited the strongest adhesion and H. pylori inhibition, warranting further in-vivo safety evaluation. Through 16S rRNA sequencing of a mouse model, BCF-01 was determined to significantly restore H. pylori-associated gastric dysbiosis and increase the abundance of potential probiotic bacteria. Furthermore, BCF-01 enhanced mucosal tight junction protein expression and inhibited the TLR4-NFκB-pyroptosis signaling pathway in macrophages, as demonstrated by qRT-PCR and western blotting.These findings highlight the potential of BCF-01 in the prevention and control of H. pylori infection. Specifically, treatment with BCF-01 effectively restored gastric microecology and improved H. pylori-mediated mucosal barrier destruction while reducing inflammation through inhibition of the TLR4-NFκB-pyroptosis signaling pathway in macrophages. BCF-01 is a promising alternative to traditional triple therapy for H. pylori infections, offering minimal side effects with high suitability for high-risk individuals.

Jute (Corchorus olitorius L.) Nanocrystalline Cellulose Inhibits Insect Virus via Gut Microbiota and Metabolism

Natural plant nanocrystalline cellulose (NCC), exhibiting a number of exceptional performance characteristics, is widely used in food fields. However, little is known about the relationship between NCC and the antiviral effect in animals. Here, we tested the function of NCC in antiviral methods utilizing honey bees as the model organism employing Israeli acute paralysis virus (IAPV), a typical RNA virus of honey bees. In both the lab and the field, we fed the IAPV-infected bees various doses of jute NCC (JNCC) under carefully controlled conditions. We found that JNCC can reduce IAPV proliferation and improve gut health. The metagenome profiling suggested that IAPV infection significantly decreased the abundance of gut core bacteria, while JNCC therapy considerably increased the abundance of the gut core bacteria Snodgrassella alvi and Lactobacillus Firm-4. Subsequent metabolome analysis further revealed that JNCC promoted the biosynthesis of fatty acids and unsaturated fatty acids, accelerated the purine metabolism, and then increased the expression of antimicrobial peptides (AMPs) and the genes involved in the Wnt and apoptosis signaling pathways against IAPV infection. Our results highlighted that JNCC could be considered as a prospective candidate agent against a viral infection.

Analysis of microbiota profile and nutritional status in male professional football players

BACKGROUND

The interest in the effect of gut microbiota on athlete health has increased in recent years. Available data indicate a relationship between gut microbiota composition and physical activity, suggesting that changes in the microbiota may contribute to the host's physical performance. Studies show that leaky gut syndrome is highly correlated with upper respiratory infections and gastrointestinal disorders in endurance sports. This study aims to reveal the relationship between microbiota profiles, and the nutritional status of football players who perform endurance exercises.

METHODS

Twenty male professional football players playing in one of the Turkish Football Federation Second League clubs participated in the study. Fecal samples were collected and stored at -86 °C, and the fecal microbiota was analyzed through 16s rRNA gene sequencing. The body composition of the football players was measured using a bioelectrical impedance analyzer. In addition, the 3-day food intake of the participants was recorded with the help of a dietitian.

RESULTS

In the microbiota of football players, four phyla, 10 genera, and four species with densities above 1% were found. Body fat percentage was observed to be negatively correlated with the species of Faecalibacterium prausnitzii and Bacteroides vulgatus and the genus of Faecalibacterium (P<0.05). Considering the nutritional status, the fat intake was found to be positively correlated with Actinobacteria and Blautia coccoides; energy and fiber intake with Prevotella and Prevotella copri (P<0.05). In addition, there was a negative correlation between carbohydrate intake and Faecalibacterium (P<0.05).

CONCLUSIONS

Our study is the first to reveal the microbiota profile of professional Turkish football players. It was found that football players' nutritional status and anthropometric measurements of are significantly related to phylum, genus and species ranks in the microbiota. These results support the bidirectional interaction between microbiota and sports. The relationship between microbiota and sports health/performance is thought to be further clarified with future studies.

Therapeutic Approach Targeting Gut Microbiome in Gastrointestinal Infectious Diseases

While emerging evidence highlights the significance of gut microbiome in gastrointestinal infectious diseases, treatments like Fecal Microbiota Transplantation (FMT) and probiotics are gaining popularity, especially for diarrhea patients. However, the specific role of the gut microbiome in different gastrointestinal infectious diseases remains uncertain. There is no consensus on whether gut modulation therapy is universally effective for all such infections. In this comprehensive review, we examine recent developments of the gut microbiome's involvement in several gastrointestinal infectious diseases, including infection of Helicobacter pylori, Clostridium difficile, Vibrio cholerae, enteric viruses, Salmonella enterica serovar Typhimurium, Pseudomonas aeruginosa Staphylococcus aureus, Candida albicans, and Giardia duodenalis. We have also incorporated information about fungi and engineered bacteria in gastrointestinal infectious diseases, aiming for a more comprehensive overview of the role of the gut microbiome. This review will provide insights into the pathogenic mechanisms of the gut microbiome while exploring the microbiome's potential in the prevention, diagnosis, prediction, and treatment of gastrointestinal infections.

Efficacy and safety of probiotic-supplemented bismuth quadruple therapy for the treatment of Helicobacter pylori infection: a systematic review and meta-analysis

OBJECTIVE

We performed a meta-analysis to determine whether the addition of probiotics to the bismuth quadruple therapy (BQT) for Helicobacter pylori would improve the incidence of eradication and reduce that of side effects.

METHODS

Randomized controlled trials matching the inclusion criteria were collected from PubMed, Embase, Web of Science, and The Cochrane Central Register of Controlled Trials. A Mantel-Haenszel random-effects model was used to calculate pooled risk ratios (RRs) and 95% confidence intervals (CIs) for the incidences of eradication rate, side effects as a whole, diarrhea, and other side effects.

RESULTS

Ten studies were selected for inclusion in the meta-analysis. The pooled RRs for the eradication rates in intention-to-treat and per-protocol analyses of the probiotic group vs. the control group were 1.07 (95% CI: 1.02-1.11) and 1.04 (95% CI: 1.00-1.07), respectively. Probiotic supplementation reduced the incidences of side effects (RR 0.58, 95% CI: 0.37-0.91), diarrhea (RR 0.41, 95% CI: 0.25-0.67), and bitter taste (RR 0.63, 95% CI: 0.40-0.99).

CONCLUSIONS

The results of this meta-analysis support the use of probiotics in combination with BQT in the clinical management of patients with H. pylori infection.

Human Gut Microbiota in Heart Failure: Trying to Unmask an Emerging Organ

There is a bidirectional relationship between the heart and the gut. The gut microbiota, the community of gut micro-organisms themselves, is an excellent gut-homeostasis keeper since it controls the growth of potentially harmful bacteria and protects the microbiota environment. There is evidence suggesting that a diet rich in fatty acids can be metabolized and converted by gut microbiota and hepatic enzymes to trimethyl-amine N-oxide (TMAO), a product that is associated with atherogenesis, platelet dysfunction, thrombotic events, coronary artery disease, stroke, heart failure (HF), and, ultimately, death. HF, by inducing gut ischemia, congestion, and, consequently, gut barrier dysfunction, promotes the intestinal leaking of micro-organisms and their products, facilitating their entrance into circulation and thus stimulating a low-grade inflammation associated with an immune response. Drugs used for HF may alter the gut microbiota, and, conversely, gut microbiota may modify the pharmacokinetic properties of the drugs. The modification of lifestyle based mainly on exercise and a Mediterranean diet, along with the use of pre- or probiotics, may be beneficial for the gut microbiota environment. The potential role of gut microbiota in HF development and progression is the subject of this review.

Effect of fucoidan on gut microbiota and its clinical efficacy in Helicobacter pylori eradication: A randomized controlled trial

OBJECTIVE

To assess the clinical efficacy of fucoidan-assisted standard quadruple therapy (SQT) in Helicobacter pylori (H. pylori) eradication and the improvement of gut microbiota.

METHODS

An open-label randomized controlled trial was conducted at the Affiliated Hospital of Qingdao University in Shandong Province, China. Ninety patients who tested positive for H. pylori were randomized to the standard quadruple therapy (SQT) group (SQ), SQT + fucoidan combination group (SF), and fucoidan + sequential SQT group (FS), respectively. Stool samples were collected for gut microbiota composition at baseline and after treatment.

RESULTS

After H. pylori eradication, the relative abundances of most conditional pathogens in the SQ decreased, while those of several beneficial bacteria increased or decreased (P < 0.05). In FS, the abundances of most beneficial bacteria increased gradually from baseline to week 12, while those of the conditional pathogens decreased (P < 0.05). The abundance of Bifidobacterium had a decreasing trend in SQ, but remained unchanged in SF and increased in FS (P < 0.05). The abundances of most beneficial bacteria were significantly higher in FS than in SQ and SF (P < 0.05). Addition of fucoidan enhanced symptom improvement during H. pylori eradication compared with SQT alone.

CONCLUSIONS

Fucoidan considerably improved gut dysbiosis during SQT for H. pylori eradication. Gut microbiota can be maintained by the addition of fucoidan before eradication therapy with SQT rather than by concomitant addition with therapy. Fucoidan-assisted SQT could relieve gastrointestinal symptoms during H. pylori eradication.

Probiotic supplementation during antibiotic treatment is unjustified in maintaining the gut microbiome diversity: a systematic review and meta-analysis

BACKGROUND

Probiotics are often used to prevent antibiotic-induced low-diversity dysbiosis, however their effect is not yet sufficiently summarized in this regard. We aimed to investigate the effects of concurrent probiotic supplementation on gut microbiome composition during antibiotic therapy.

METHODS

We performed a systematic review and meta-analysis of randomized controlled trials reporting the differences in gut microbiome diversity between patients on antibiotic therapy with and without concomitant probiotic supplementation. The systematic search was performed in three databases (MEDLINE (via PubMed), Embase, and Cochrane Central Register of Controlled Trials (CENTRAL)) without filters on 15 October 2021. A random-effects model was used to estimate pooled mean differences (MD) with 95% confidence intervals (CI). This review was registered on PROSPERO (CRD42021282983).

RESULTS

Of 11,769 identified articles, 15 were eligible in the systematic review and 5 in the meta-analyses. Quantitative data synthesis for Shannon (MD = 0.23, 95% CI: [(-)0.06-0.51]), Chao1 (MD = 11.59 [(-)18.42-41.60]) and observed OTUs (operational taxonomic unit) (MD = 17.15 [(-)9.43-43.73]) diversity indices revealed no significant difference between probiotic supplemented and control groups. Lacking data prevented meta-analyzing other diversity indices; however, most of the included studies reported no difference in the other reported α- and ß-diversity indices between the groups. Changes in the taxonomic composition varied across the eligible studies but tended to be similar in both groups. However, they showed a potential tendency to restore baseline levels in both groups after 3-8 weeks. This is the first meta-analysis and the most comprehensive review of the topic to date using high quality methods. The limited number of studies and low sample sizes are the main limitations of our study. Moreover, there was high variability across the studies regarding the indication of antibiotic therapy and the type, dose, and duration of antimicrobials and probiotics.

CONCLUSIONS

Our results showed that probiotic supplementation during antibiotic therapy was not found to be influential on gut microbiome diversity indices. Defining appropriate microbiome diversity indices, their standard ranges, and their clinical relevance would be crucial.

Probiotics and autoprobiotics for treatment of Helicobacter pylori infection

The article discusses various approaches for probiotic treatment of Helicobacter pylori (H. pylori) infection: Probiotics as an adjuvant treatment in the standard eradication therapy; probiotic strains as a monotherapy; and autoprobiotics as a monotherapy. Autoprobiotics refer to indigenous bifidobacteria, lactobacilli, or enterococci isolated from a specific individual, intended to restore his/her microbiota and improve his/her health. The potential mechanisms of probiotic action against H. pylori include correction of the gut microbiota, immunological effects (enhancement of humoral and cellular immunity, and reduction of oxidative stress), direct antagonistic effects against H. pylori (such as colonization resistance and bacteriocin synthesis), and stimulation of local immunological protection (strengthening of the mucous protective barrier and reduction of gastric mucosa inflammation). The incorporation of probiotics into comprehensive eradication therapy shows promise in optimizing the treatment of H. pylori infection. Probiotics can enhance the eradication rates of H. pylori, reduce the occurrence and severity of side effects, and improve patient compliance. Probiotic or autoprobiotic monotherapy can be considered as an alternative treatment approach in cases of allergic reactions and insufficient effectiveness of antibiotics. We recommend including probiotics as adjunctive medications in anti-H. pylori regimens. However, further randomized multicenter studies are necessary to investigate the effects of probiotics and autoprobiotics against H. pylori, in order to gain a better understanding of their mechanisms of action.

The Eradication of Helicobacter pylori Was Significantly Associated with Compositional Patterns of Orointestinal Axis Microbiota

BACKGROUND

Helicobacter pylori (H. pylori) is significantly linked to various diseases that seriously impact human health, such as gastric ulcers, chronic gastritis and gastric adenocarcinoma.

METHODS

The compositional shifts in bacterial communities of the orointestinal axis were surveyed pre/post-eradication of H. pylori. In total, 60 samples, including stool and salivary specimens, were collected from 15 H. pylori-positive individuals (HPP) before beginning and 2 months after receiving the eradication therapy. The V3-V4 regions of the 16S rRNA gene were sequenced using MiSeq.

RESULTS

Overall, oral microbiomes were collectively more diverse than the gut microbiomes (Kruskal-Wallis; p = 3.69 × 10^-5). Notably, the eradication of H. pylori was associated with a significant reduction in the bacterial diversity along the orointestinal axis (Wilcoxon rank sum test; p = 6.38 × 10^-3). Interestingly, the oral microbiome of HPP showed a positive correlation between Proteobacteria and Fusobacteria, in addition to a significant predominance of Streptococcus, in addition to Eubacterium_eligens, Haemophilus, Ruminococcaceae, Actinomyces and Staphylococcus. On the other hand, Fusobacterium, Veillonella, Catenibacterium, Neisseria and Prevotella were significantly enriched upon eradication of H. pylori. Generally, Bacteroidetes and Fusobacteria positively coexisted during H. pylori infection along the orointestinal axis (r = 0.67; p = 0.0006). The eradication of H. pylori was positively linked to two distinctive orotypes (O3 and O4). Orotype O4 was characterized by a robust abundance of Veillonella and Fusobacteria. The gut microbiomes during H. pylori infection showed a remarkable predominance of Clostridium_sensu_stricto_1 and Escherichia_Shigella. Likewise, Bifidobacterium and Faecalibacterium were significantly enriched upon eradication of H. pylori.

CONCLUSIONS

Finally, the impact of eradication therapy clearly existed on the representation of certain genera, especially in the oral microbiome, which requires particular concern in order to counteract and limit their subsequent threats.

2022 Chinese national clinical practice guideline on Helicobacter pylori eradication treatment

BACKGROUND

Helicobacter pylori ( H. pylori ) infection is an infectious disease with a prevalence rate of up to 50% worldwide. It can cause indigestion, gastritis, peptic ulcer, and gastric cancer. H. pylori eradication treatment can effectively control disease progression and reduce the risk of the above conditions. However, the escalating trend of antibiotic resistance presents a global challenge for H. pylori eradication. We aim to provide guidance on pharmacological treatment of H. pylori infection.

METHODS

This clinical practice guideline is developed following the World Health Organization's recommended process, adopting Grading of Recommendations Assessment, Development and Evaluation in assessing evidence quality, and utilizing Evidence to Decision framework to formulate clinical recommendations, minimizing bias and increasing transparency of the clinical practice guideline development process. We used the Reporting Items for practice Guidelines in HealThcare (RIGHT) statement and The Appraisal of Guidelines for Research and Evaluation II (AGREE II) as reporting and conduct guides to ensure the guideline's completeness and transparency.

RESULTS

Though decreasing in developed countries, the prevalence of H. pylori remains high in developing countries, causing a major public health burden. This clinical practice guideline contains 12 recommendations concerning pharmacological treatment for H. pylori eradication. Among them, it is worth highlighting that bismuth preparations are inexpensive, safe, and effective, consequently making bismuth quadruple therapy a preferred choice for initial and rescue treatment. In empirical treatment, high-dose dual therapy is equally effective compared with bismuth quadruple therapy.

CONCLUSIONS

The 12 recommendations in this clinical practice guideline are formed with consideration for stakeholders' values and preferences, resource use, feasibility, and acceptability. Recommendations are generalizable to resource limited settings with similar antibiotic resistance pattern as China, and lower middle-income countries facing comparable sociological and technical challenges.

REGISTRATION

Guidelines International Network (GIN) website, https://guidelines.ebmportal.com/node/69996 .

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.

Validity of food additive maltodextrin as placebo and effects on human gut physiology: systematic review of placebo-controlled clinical trials

PURPOSE

Maltodextrin (MDX) is a polysaccharide food additive commonly used as oral placebo/control to investigate treatments/interventions in humans. The aims of this study were to appraise the MDX effects on human physiology/gut microbiota, and to assess the validity of MDX as a placebo-control.

METHODS

We performed a systematic review of randomized-placebo-controlled clinical trials (RCTs) where MDX was used as an orally consumed placebo. Data were extracted from study results where effects (physiological/microbial) were attributed (or not) to MDX, and from study participant outcomes data, before-and-after MDX consumption, for post-publication 're-analysis' using paired-data statistics.

RESULTS

Of two hundred-sixteen studies on 'MDX/microbiome', seventy RCTs (n = 70) were selected for analysis. Supporting concerns regarding the validity of MDX as a placebo, the majority of RCTs (60%, CI 95% = 0.48-0.76; n = 42/70; Fisher-exact p = 0.001, expected < 5/70) reported MDX-induced physiological (38.1%, n = 16/42; p = 0.005), microbial metabolite (19%, n = 8/42; p = 0.013), or microbiome (50%, n = 21/42; p = 0.0001) effects. MDX-induced alterations on gut microbiome included changes in the Firmicutes and/or Bacteroidetes phyla, and Lactobacillus and/or Bifidobacterium species. Effects on various immunological, inflammatory markers, and gut function/permeability were also documented in 25.6% of the studies (n = 10/42). Notably, there was considerable variability in the direction of effects (decrease/increase), MDX dose, form (powder/pill), duration, and disease/populations studied. Overall, only 20% (n = 14/70; p = 0.026) of studies cross-referenced MDX as a justifiable/innocuous placebo, while 2.9% of studies (n = 2/70) acknowledged their data the opposite.

CONCLUSION

Orally-consumed MDX often (63.9% of RCTs) induces effects on human physiology/gut microbiota. Such effects question the validity of MDX as a placebo-control in human clinical trials.

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.

Effects of probiotics on gastric microbiota and its precombination with quadruple regimen for Helicobacter pylori eradication

OBJECTIVES

This study aimed to assess the efficacy and safety of probiotics for Helicobacter pylori (H. pylori) eradication therapy as well as their effects on gastric microbiota.

METHODS

Patients who had failed H. pylori eradication therapy for at least twice were prospectively enrolled during March 2019 and March 2021. A 2-week administration of compound Lactobacillus acidophilus probiotic (1 g thrice daily) followed by a 10-day quadruple bismuth-containing H. pylori eradication therapy was administrated. Endoscopy was performed, and gastric biopsy samples were obtained for drug sensitivity testing and 16S rRNA gene sequencing before and after probiotic treatment. Eradication was evaluated by the ¹³ C-urea breath test at least 4 weeks after treatment completion. Adverse events (AEs) were recorded.

RESULTS

Thirty-seven patients were included. Probiotic supplementation had no effects on the diversity, community structure, and composition of gastric microbiota and no inhibition on H. pylori activity. However, it increased some of the beneficial bacteria such as Blautia, Dorea, and Roseburia (P < 0.05). The overall eradication rate was 97.3% (95% confidence interval [CI] 91.8%-100%). AEs, mainly dizziness, nausea, diarrhea, and chest distress, were detected in six individuals, all of which were resolved upon cessation of antibiotic administration. Dyspeptic symptoms were improved after probiotic supplementation and at treatment completion (both P < 0.001).

CONCLUSIONS

H. pylori-infected individuals might benefit from probiotics followed by a quadruple bismuth-containing eradication therapy. Further studies with large sample sizes are warranted.

Metagenomic Changes of Gut Microbiota following Treatment of Helicobacter pylori Infection with a Simplified Low-Dose Quadruple Therapy with Bismuth or Lactobacillus reuteri

Background: Probiotic supplementation to antibiotic regimens against Helicobacter pylori infection has been proposed to improve eradication rate and to decrease detrimental effects on gut microbiota. Aims: To evaluate microbiota modifications due to a low-dose quadruple therapy with bismuth or Lactobacillus reuteri. Methods: Forty-six patients infected with H. pylori were prospectively enrolled in a single-centre, randomized controlled trial to receive b.i.d. with meals for 10 days low-dose quadruple therapy consisting of rabeprazole 20 mg and bismuth (two capsules of Pylera® plus 250 mg each of tetracycline and metronidazole), or the same dose of rabeprazole and antibiotics plus Gastrus® (L. reuteri), one tablet twice-a-day for 27 days. Stool samples were collected at the enrolment, at the end and 30–40 days after the treatment. Gut microbiota composition was investigated with 16S rRNA gene sequencing. Results: Eradication rate was by ITT 78% in both groups, and by PP analysis 85.7% and 95.5% for Gastrus® and bismuth group, respectively. Alpha and beta diversity decreased at the end of treatment and was associated with a reduction of bacterial genera beneficial for gut homeostasis, which was rescued 30–40 days later in both groups, suggesting a similar impact of the two regimens in challenging bacterial community complexity. Conclusions: Low-dose bismuth quadruple therapy proved to be effective with lower costs and amount of antibiotics and bismuth. Gastrus® might be an option for patients with contraindications to bismuth. L. reuteri was unable to significantly counteract dysbiosis induced by antibiotics. How to administer probiotics to prevent gut microbiota alterations remains an open question.

Effect of Probiotic-Assisted Eradication of cagA+/vacA s1m1 Helicobacter pylori on Intestinal Flora

Objective. We attempted to evaluate the effects of probiotic-assisted eradication of cytotoxin-associated gene A (cagA)+/vacuolating cytotoxin A (vacA) s1m1 Helicobacter pylori (H. pylori) on the intestinal flora, inflammatory factors, and clinical outcomes. Methods. A total of 180 patients with cagA+/vacA s1m1 H. pylori were randomly divided into two groups. Group A was treated with bismuth quadruple therapy (BQT). Group B was treated with S. boulardii in addition to BQT. The distribution of intestinal flora, serum interleukin-8 (IL-8), IL-17, tumor necrosis factor-α (TNF-α) levels, recovery time of clinical symptoms, total effective rate of clinical symptoms, H. pylori eradication rate, and adverse reactions were observed. Results. 2 weeks after treatment, the contents of Bifidobacterium, Bacteroides, and Lactobacillus in the intestinal tract of Group A decreased, while the amounts of Enterococcus and Enterobacter increased. In Group B, the contents of Bifidobacterium, Bacteroides, and Lactobacillus increased, while the amounts of Enterococcus and Enterobacter did not change significantly. Moreover, the trend of this flora change was still present at 4 weeks after treatment. Compared with Group A, Group B had lower IL-8, IL-17, and TNF-α levels, shorter recovery time of clinical symptoms, higher overall efficiency of clinical symptoms, and lower occurrence of adverse reactions. The eradication rate did not differ significantly between the two groups. Conclusion. BQT can lead to intestinal flora disorders in cagA+/vacA s1m1 H. pylori patients. S. boulardii can improve the distribution of intestinal flora, downregulate immune-inflammatory mediators, and modify clinical symptoms in patients.

Effects of non-viable Lactobacillus reuteri combining with 14-day standard triple therapy on Helicobacter pylori eradication: A randomized double-blind placebo-controlled trial

BACKGROUND

Viable probiotics have shown effects on the eradication of Helicobacter pylori, but the role of non-viable probiotics in H. pylori eradication is unclear. This study aimed to evaluate the effects of non-viable Lactobacillus reuteri DSM17648 combining with 14-day standard triple therapy on H. pylori eradication.

MATERIALS AND METHODS

Two hundred treatment-naive H. pylori-positive adult patients were randomized equally to receive non-viable L. reuteri DSM17648 (LR group) or placebo for 4 weeks, with the latter 2 weeks treated together with triple therapy. The Gastrointestinal Symptom Rating Scale (GSRS) was completed before and after treatment. Stool samples were collected for 16S rRNA gene sequencing at week0, week2, and week8.

RESULTS

Eradication rates in the LR group and the placebo group were 81.8% and 83.7% in ITT analysis (p = 0.730), 86.2% and 87.2% in PP analysis (p = 0.830), respectively. After treatment, the mean GSRS score decreased significantly in the LR group as compared with the placebo group (1.9 ± 0.2 vs. 2.7 ± 0.3; p = 0.030). Significantly less patients in the LR group as compared with the placebo group reported abdominal distention (5.1% vs. 16.3%; p = 0.010) and diarrhea (11.1% vs. 23.5%; p = 0.022). The relative abundance of Proteobacteria phylum and Escherichia-Shigella genus in the placebo group was about 4.0-fold and 8.1-fold of that in the LR group at wk2, respectively. Significant changes of diversity and enhancements of Fusicatenibacter, Subdoligranulum, and Faecalibacterium were observed in the LR group compared with the placebo group.

CONCLUSIONS

Supplementation of non-viable L. reuteri DSM17648 with triple therapy did not improve the eradication rate of H. pylori, but it helped to build up a beneficial microbial profile and reduced the frequencies of abdominal distention, diarrhea, and the GSRS score.

Helicobacter pylori Infection in Geriatric Patients: Current Situation and Treatment Regimens

Helicobacter pylori (H. pylori) has so far infected more than half the global population. It is the most important and controllable risk factor for gastric cancer. The elderly, who are at a higher incidence of the infection, are also commonly found to develop antibiotic resistance. The symptoms, diagnosis, clinical features (of gastric or extra-digestive diseases), and treatment of H. pylori infection in the elderly, are different from that in the non-elderly. Health conditions, including comorbidities and combined medication have limited the use of regular therapies in elderly patients. However, they can still benefit from eradication therapy, thus preventing gastric mucosal lesions and gastric cancer. In addition, new approaches, such as dual therapy and complementary therapy, have the potential to treat older patients with H. pylori infection.

Characterization of gut microbiome and metabolome in Helicobacter pylori patients in an underprivileged community in the United States

BACKGROUND

Helicobacter pylori (H. pylori), a bacterium that infects approximately half of the world’s population, is associated with various gastrointestinal diseases, including peptic ulcers, non-ulcer dyspepsia, gastric adenocarcinoma, and gastric lymphoma. As the burden of antibiotic resistance increases, the need for new adjunct therapies designed to facilitate H. pylori eradication and reduce negative distal outcomes associated with infection has become more pressing. Characterization of the interactions between H. pylori, the fecal microbiome, and fecal fatty acid metabolism, as well as the mechanisms underlying these interactions, may offer new therapeutic approaches.

AIM

To characterize the gut microbiome and metabolome in H. pylori patients in a socioeconomically challenged and underprivileged inner-city community.

METHODS

Stool samples from 19 H. pylori patients and 16 control subjects were analyzed. 16S rRNA gene sequencing was performed on normalized pooled amplicons using the Illumina MiSeq System using a MiSeq reagent kit v2. Alpha and beta diversity analyses were performed in QIIME 2. Non-targeted fatty acid analysis of the samples was carried out using gas chromatography-mass spectrometry, which measures the total content of 30 fatty acids in stool after conversion into their corresponding fatty acid methyl esters. Multi-dimensional scaling (MDS) was performed on Bray-Curtis distance matrices created from both the metabolomics and microbiome datasets and a Procrustes test was performed on the metabolomics and microbiome MDS coordinates.

RESULTS

Fecal microbiome analysis showed that alpha diversity was lowest in H. pylori patients over 40 years of age compared to control subjects of similar age group. Beta diversity analysis of the samples revealed significant differences in microbial community structure between H. pylori patients and control subjects across all ages. Thirty-eight and six taxa had lower and higher relative abundance in H. pylori patients, respectively. Taxa that were enriched in H. pylori patients included Atopobium, Gemellaceae, Micrococcaceae, Gemellales and Rothia (R. mucilaginosa). Notably, relative abundance of the phylum Verrucomicrobia was decreased in H. pylori patients compared to control subjects. Procrustes analysis showed a significant relationship between the microbiome and metabolome datasets. Stool samples from H. pylori patients showed increases in several fatty acids including the polyunsaturated fatty acids (PUFAs) 22:4n6, 22:5n3, 20:3n6 and 22:2n6, while decreases were noted in other fatty acids including the PUFA 18:3n6. The pattern of changes in fatty acid concentration correlated to the Bacteroidetes:Firmicutes ratio determined by 16S rRNA gene analysis.

CONCLUSION

This exploratory study demonstrates H. pylori-associated changes to the fecal microbiome and fecal fatty acid metabolism. Such changes may have implications for improving eradication rates and minimizing associated negative distal outcomes.

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.