Significant Reduction in Helicobacter pylori Load in Humans with Non-viable Lactobacillus reuteri DSM17648: A Pilot Study

Lactobacillus reuteri compared with placebo as an adjuvant in Helicobacter pylori eradication therapy: a meta-analysis of randomized controlled trials

Background

Given the growing problem of antibiotic resistance, it is crucial to improve Helicobacter pylori (H. pylori) treatment interventions or provide adjunctive therapy. The objective of this meta-analysis was to evaluate whether Lactobacillus reuteri (L. reuteri) could improve H. pylori eradication rate, reduce the incidence of adverse events (AEs), and alleviate gastrointestinal symptoms.

Design

A meta-analysis of randomized controlled trials (RCTs) comparing L. reuteri supplementation therapy with placebo was conducted.

Sources and methods

We retrieved relevant studies from PubMed, Embase, and the Cochrane Library. The primary outcome was H. pylori eradication rate, and the scores on the Gastrointestinal Symptom Rating Scale and AEs were secondary outcomes.

Results

Eight RCTs including 1087 patients were included in this analysis. The L. reuteri supplementation group showed significantly higher H. pylori eradication rates in both intention-to-treat (ITT) and per-protocol (PP) analysis [ITT: 80.0% versus 72.6%; p = 0.005, relative risk (RR): 1.10; 95% confidence interval (CI): 1.03-1.17; number needed to treat (NNT) = 14; PP: 81.8% versus 75.0%; p = 0.006, RR: 1.09; 95% CI: 1.03-1.16; NNT = 15]. Patients treated with L. reuteri showed greater improvements in gastrointestinal symptoms (pooled mean difference: -2.43, 95% CI: -4.56 to -0.29, p = 0.03). The incidence of AEs was significantly reduced in the L. reuteri supplementation group based on ITT and PP analysis (ITT: p < 0.00001, RR: 0.72, 95% CI: 0.67-0.78; PP: p < 0.00001, RR: 0.70, 95% CI: 0.65-0.77).

Conclusion

The present meta-analysis demonstrated that supplementation with L. reuteri was beneficial for improving the eradication rate of H. pylori, reducing the overall incidence of side effects, and relieving gastrointestinal symptoms in patients during treatment. The findings provide new insights into clinical decision-making.

Trial registration PROSPERO

CRD42023424052.

A Bifidobacterium animalis subsp. lactis strain that can suppress Helicobacter pylori: isolation, in vitro and in vivo validation

The administration of probiotics is an effective approach for treatment of Helicobacter pylori, which is associated with human gastrointestinal diseases and cancers. To explore more effective probiotics for H. pylori infection elimination, bacteria from infant feces were screened in this study. We successfully isolated the Bifidobacterium animalis subsp. lactis strains and evaluated its efficacy to inhibit H. pylori growth in vitro and in vivo. The results showed that a B. animalis strain (named BB18) sustained a high survival rate after incubation in gastric juice. The rapid urease test suggested that B. animalis BB18 reduced pathogen loads in H. pylori-infected Mongolian gerbils. Alleviation of H. pylori infection-induced gastric mucosa damage and decreased levels inflammatory cytokines were observed after the B. animalis BB18 administration. These findings demonstrated that B. animalis BB18 can inhibit H. pylori infection both in vitro and in vivo, suggesting its potential application for the prevention and eradication therapy of H. pylori infection.

Lactobacilli and Klebsiella: Two Opposites in the Fight for Human Health

The problem of antibiotic resistance is currently very acute. Numerous research and development of new antibacterial drugs are being carried out that could help cope with various infectious agents. One of the promising directions for the search for new antibacterial drugs is the search among the probiotic strains present in the human gastrointestinal tract. This review is devoted to characteristics of one of these probiotic strains that have been studied to date: Limosilactobacillus reuteri. The review discusses its properties, synthesis of various compounds, as well as role of this strain in modulating various systems of the human body. The review also examines key characteristics of one of the most harmful among the currently known pathogenic organisms, Klebsiella, which is significantly resistant to antibiotics existing in medical practice, and also poses a great threat of nosocomial infections. Discussion of characteristics of the two strains, which have opposite effects on human health, may help in creation of new effective antibacterial drugs without significant side effects.

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.

Study of the effect of Lactobacillus crispatus FSCDJY67L3 on Helicobacter Pylori eradication: a double-blind randomized controlled clinical trial

Helicobacter pylori (H. pylori) is a gram-negative bacterium exhibiting high pathogenicity. Traditional antibiotic treatments are considered ineffective as the H. pylori resistance has increased. Recently, a quadruple therapy strategy of probiotics and antibiotics to eliminate H. pylori was proposed. Probiotics play a therapeutic role as supplements in this process. The present research screened a probiotic strain (Lactobacillus crispatus FSCDJY67L3) that co-aggregates strongly with H. pylori. L. crispatus FSCDJY67L3 was demonstrated to significantly reduce H. pylori load (14C breath test) in clinical trials with H. pylori-positive patients. The Gastrointestinal Symptom Rating Scale (GSRS) score decreased, indicating improvement in the gastrointestinal discomfort of patients. Furthermore, L. crispatus FSCDJY67L3 showed no change in the structure of the intestinal flora of patients. Routine blood indices and blood biochemical indices related to liver and kidney function were also not affected in the patients. Therefore, L. crispatus FSCDJY67L3 may be used clinically as a supplement for the treatment of H. pylori.

Clinical Trial Registration

https://www.chictr.org.cn/, Chinese Clinical Trial Registry (ChiCTR2100053710).

Lactiplantibacillus plantarum ZJ316 Reduces Helicobacter pylori Adhesion and Inflammation by Inhibiting the Expression of Adhesin and Urease Genes

SCOPE

The present study aims to investigate the anti-Helicobacter pylori (H. pylori) effects of Lactiplantibacillus plantarum ZJ316 (L. plantarum ZJ316) both in vitro and in vivo.

METHODS AND RESULTS

This study finds that L. plantarum ZJ316 effectively suppresses H. pylori adhesion in inhibition (Pre-ZJ316), competition (Co-ZJ316), and displacement (Post-ZJ316) assays, and Pre-ZJ316 displaying the most potent inhibitory effect with an impressive inhibition ratio of 70.14%. Upon anti-adhesion, L. plantarum ZJ316 significantly downregulates the expression of H. pylori virulence genes, including ureA, ureB, flaA, and sabA, with inhibition ratios of 46.83%, 24.02%, 21.42%, and 62.38% at 2 h, respectively. In addition, L. plantarum ZJ316 is observed to reduce the level of interleukin 8 (IL-8) and improve cell viability in infected AGS cells. Furthermore, in vivo studies show that supplementation with L. plantarum ZJ316 effectively hinders H. pylori colonization and significantly suppresses the infiltration of immune cells and IL-8 production with H. pylori infection, protecting host from inflammatory damage.

CONCLUSION

L. plantarum ZJ316 exhibits excellent adhesion inhibition on H. pylori, and may be used as a probiotic candidate in the prevention or adjuvant therapy of gastric disease caused by H. pylori.

Lactobacillus reuteri in digestive system diseases: focus on clinical trials and mechanisms

Objectives

Digestive system diseases have evolved into a growing global burden without sufficient therapeutic measures. Lactobacillus reuteri (L. reuteri) is considered as a new potential economical therapy for its probiotic effects in the gastrointestinal system. We have provided an overview of the researches supporting various L. reuteri strains' application in treating common digestive system diseases, including infantile colic, diarrhea, constipation, functional abdominal pain, Helicobacter pylori infection, inflammatory bowel disease, diverticulitis, colorectal cancer and liver diseases.

Methods

The summarized literature in this review was derived from databases including PubMed, Web of Science, and Google Scholar.

Results

The therapeutic effects of L. reuteri in digestive system diseases may depend on various direct and indirect mechanisms, including metabolite production as well as modulation of the intestinal microbiome, preservation of the gut barrier function, and regulation of the host immune system. These actions are largely strain-specific and depend on the activation or inhibition of various certain signal pathways. It is well evidenced that L. reuteri can be effective both as a prophylactic measure and as a preferred therapy for infantile colic, and it can also be recommended as an adjuvant strategy to diarrhea, constipation, Helicobacter pylori infection in therapeutic settings. While preclinical studies have shown the probiotic potential of L. reuteri in the management of functional abdominal pain, inflammatory bowel disease, diverticulitis, colorectal cancer and liver diseases, its application in these disease settings still needs further study.

Conclusion

This review focuses on the probiotic effects of L. reuteri on gut homeostasis via certain signaling pathways, and emphasizes the importance of these probiotics as a prospective treatment against several digestive system diseases.

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.

Characterization of adhesion, anti-adhesion, co-aggregation, and hydrophobicity of Helicobacter pylori and probiotic strains

Objectives

To characterize the adhesion ability of nine Helicobacter pylori strains and eight probiotics in human oral keratinocyte cells (H357 cells) in comparison to intestinal cells (Caco-2 and HIEC-6 cells). Subsequently, the anti-adhesion and co-aggregation abilities of the selected probiotic strains on H. pylori strains were investigated.

Methods

Nine H. pylori strains, including H. pylori ATCC43504 (type strain), and 8 clinical strains, were isolated from oral samples of three patients (one non-disease, one gastritis patient, and one gastric cancer patient). Eight selected probiotic strains were used, as follows: Lacticaseibacillus paracasei SD1, Lacticaseibacillus rhamnosus SD4, L. rhamnosus SD11, Limosilactobacillus fermentum SD7, L. rhamnosus GG, Limosilactobacillus reuteri ATCC-PTA6475, Lacticaseibacillus casei Shirota, and L. paracasei CNCM I-1572. The adhesion and anti-adhesion abilities of H. pylori and the probiotic strains were investigated in H357, Caco-2, and HIEC-6 cells. Co-aggregation at various pHs, hydrophobicity, and surface receptors of the cell lines for H. pylori strains were examined.

Results

All probiotic and H. pylori strains adhered to H357 significantly better than Caco-2, and HIEC-6 cells. Three probiotic strains (SD7, SD4, SD11) showed significantly higher adhesion than others. Of the clinical H. pylori strains, isolates from a gastric cancer patient had the highest adhesion ability to all of the cell lines tested. Probiotic strains that exhibited high adhesion ability provided high anti-adhesion and co-aggregation against H. pylori strains. Acidic conditions encouraged the co-aggregation of probiotics to H. pylori strains.

Conclusion

This study provides information relating to the adhesion abilities of clinical H. pylori and probiotic strains to the oral mucosa when compared to the intestinal mucosa. Certain probiotic strains may be useful for the successful eradication of H. pylori infection via anti-adhesion and co-aggregation.

Current and future perspectives for Helicobacter pylori treatment and management: From antibiotics to probiotics

Helicobacter pylori (H. pylori) is a Gram-negative anaerobic bacterium that colonizes the human stomach and is the leading cause of gastric diseases such as chronic gastritis and peptic ulcers, as well as the most definite and controllable risk factor for the development of gastric cancer. Currently, the regimen for H. pylori eradication has changed from triple to quadruple, the course of treatment has been extended, and the type and dose of antibiotics have been adjusted, with limited improvement in efficacy but gradually increasing side effects and repeated treatment failures in an increasing number of patients. In recent years, probiotics have become one of the most important tools for supporting intestinal health and immunity. Numerous in vitro studies, animal studies, and clinical observations have demonstrated that probiotics have the advantage of reducing side effects and increasing eradication rates in adjuvant anti-H. pylori therapy and are a valuable supplement to conventional therapy. However, many different types of probiotics are used as adjuncts against H. pylori, in various combinations, with different doses and timing, and the quality of clinical studies varies, making it difficult to standardize the results. In this paper, we focus on the risk, status, prevention, control, and treatment of H. pylori infection and review international consensus guidelines. We also summarize the available scientific evidence on using Limosilactobacillus reuteri (L. reuteri) as a critical probiotic for H. pylori treatment and discuss its clinical research and application from an evidence-based perspective.

Investigating the effect of quadruple therapy with Saccharomyces boulardii or Lactobacillus reuteri strain (DSMZ 17648) supplements on eradication of Helicobacter pylori and treatments adverse effects: a double-blind placebo-controlled randomized clinical trial

Background

The goal of this study was to investigate the effects of treatment with Saccharomyces boulardii and Lactobacillus reuteri on the eradication of Helicobacter pylori and Adverse effects (AEs) of the treatment.

Results

This study was a double-blind, randomized, placebo-controlled trial. And, eradication of H. pylori was reported comparing quadruple therapy include of PPI (proton pomp inhibitor), bismuth subcitrate, clarithromycin, and amoxicillin versus quadruple therapy supplemented with S. boulardii and L. reuteri DSMZ 17648. For this aim, a total of 156 patients were included in the current study; and patients positive for H. pylori infection (n = 156) were randomly assigned to 3 groups: 52 patients (Group P) received conventional quadruple therapy plus L. reuteri, 52 patients (Group S) received conventional quadruple therapy plus S. boulardii daily, for 2 weeks, and 52 patients were in the control group (Group C). At the end of the treatment period, all the subjects continued to take proton pump inhibitor (PPI) alone for 14 days, and then, no medication was given for 2 weeks again. During follow-up, gastrointestinal symptoms were assessed using an evaluation scale (Glasgow dyspepsia questionnaire [GDQ]), and AEs were assessed at 7, 14, 21, and 28 days. As a result, all patients completed the treatment protocol in all groups by the end of the study. Additionally, eradication therapy was effective for 94.2% of subjects in Group S, 92.3% of subjects in Group P, and 86.5% of subjects in the control group, with no differences between treatment arms. In Group S, the chance of developing symptoms of nausea (OR = 2.74), diarrhea (OR = 3.01), headache (OR = 10.51), abdominal pain (OR = 3.21), and anxiety (OR = 3.58) was significantly lower than in the control group (p < 0.05).

Conclusion

S. boulardii could significantly reduce some AEs of H. pylori eradication therapy, but effectiveness of Lactobacillus reuteri on these cases was not significant. It is recommended to conduct the future research with larger sample size in order to investigate the effect.

Trial registration: IRCT20200106046021N1, this trial was registered on Jan 14, 2020.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12876-022-02187-z.

Lactobacillus crispatus DSM25988 as novel bioactive agent to co-aggregate Streptococcus pyogenes and to exclude it by binding to human cells

Streptococcus pyogenes, a group A streptococcus, is the major bacterial pathogen responsible for acute bacterial infection of the human oropharynx and the causative agent of scarlet fever. Estimates of the global burden of S. pyogenes related diseases revealed 616 million cases of pharyngitis, and at least 517,000 deaths due to severe invasive diseases and sequelae. Here we describe Lactobacillus crispatus DSM25988 that was identified among hundreds of Lactobacillus strains (referring to all organisms that were classified as Lactobacillaceae until 2020) showing ability to prevent adhesion of S. pyogenes to Detroit 562 cells, and to exhibit a masking and co-aggregating effect on S. pyogenes in vitro. L. crispatus DSM25988 also inhibits invasion of cultured human epithelial pharyngeal cells by S. pyogenes. Competitive binding to fibronectin might be involved in the inhibition process. Antiviral activity of the L. crispatus DSM25988 cells were identified in an in vitro cell model demonstrating that L. crispatus effectively excludes viruses from epithelial cells using SARS-CoV2 proteins as a model. This finding points to the potential of DSM25988 to protect cells from virus infection. Biological activity is retained in heat treated cells. The heat-treated Lactobacillus strain was further developed into functional throat lozenges, wherein its biological activity is stably maintained in the formulation. Lozenges containing L. crispatus DSM25988 underwent testing in an uncontrolled, prospective user study in 44 subjects with symptoms of sore throat for a period of up to 14 days. The study data shows promising safety and efficacy of the medical device when used against symptoms of sore throat like scratchy feeling, hoarse voice and swallowing pain.

Probiotics in the treatment of Helicobacter pylori infection: reality and perspective

Helicobacter pylori (H. pylori) infection is one of the most common in the world today, associated with the development of acute or chronic inflammatory diseases of the gastroduodenal tract. In order to eradicate the pathogen, various antibacterial therapy regimens have been proposed, based on the use of several chemotherapeutic drugs and a proton pump inhibitor (PPI). However, recent studies indicate a decrease in antibiotic effectiveness due to both the growth rate of H. pylori resistance and side effects, often due to the development of dysbiosis. One of the promising areas of investigation is the treatment with probiotic therapy of helicobacteriosis. The use of probiotics, in the context of H. pylori infection, has two main reasons. The first is related to the use of certain probiotics to reduce the frequency of undesirable gastrointestinal consequences during H. pylori eradication therapy. The second is associated with the antagonistic effect of individual probiotics on H. pylori and the potentiation of the eradication effect. The purpose of this review was to summarize the latest data on the use of probiotics to enhance H. pylori eradication and to restore the gastrointestinal microbiota. Many unresolved questions, about the choice of the specific composition of the probiotic cocktail, dosage, duration of therapy, mechanisms of the antimicrobial action of probiotics, as well as possible negative consequences of such therapy, remain.

The efficacy of Lactobacillus acidophilus and rhamnosus in the reduction of bacterial load of Helicobacter pylori and modification of gut microbiota-a double-blind, placebo-controlled, randomized trial

BACKGROUND

Probiotics may alter the gut microbiota and may reduce antibiotic-related dysbiosis after H. pylori eradication. However, whether probiotics are effective in reducing the bacterial load of H. pylori and modifying the gut microbiota remains unknown. We aimed to assess the efficacy of Lactobacillus acidophilus and Lactobacillus rhamnosus in reducing the bacterial load of H. pylori and modifying the gut microbiota.

MATERIALS AND METHODS

In this double-blind, randomized, placebo-controlled trial, we recruited 40 adult subjects with moderate to high bacterial loads of H. pylori, defined as a mean delta over baseline (DOB) value of the ¹³ C-urea breath test (¹³ C-UBT) of 10 or greater every 4 days 6 times. Eligible subjects were randomized in a 1:1 ratio to receive either probiotics containing Lactobacillus acidophilus and Lactobacillus rhamnosus or placebo twice daily for 4 weeks. ¹³ C-UBT was measured weekly from the beginning of treatment to 2 weeks after treatment. Amplification of the V3 and V4 hypervariable regions of the 16S rRNA was performed for fecal microbiota.

RESULTS

A total of 40 subjects were randomized to receive probiotics or placebo. The DOB value was significantly lower in the probiotic group than in the placebo group after 4 weeks of treatment (26.0 vs. 18.5, p = .045). The DOB value was significantly reduced compared to that at baseline in the probiotic group (18.5 vs. 26.7, p = .001) but not in the placebo group (26.0 vs. 25.0, p = .648). However, the eradication rate for H. pylori was 0% in both groups. There was no significant difference in the DOB values between the two groups 1 and 2 weeks after discontinuation of the probiotics. There were also no significant changes observed in the α-diversity and β-diversity at week 4 compared to baseline in the probiotic group (p = .77 and 0.91) and the placebo group (p = .26 and 0.67).

CONCLUSIONS

Although the use of Lactobacillus acidophilus and Lactobacillus rhamnosus may reduce the bacterial load of H. pylori, there were no significant changes in the composition of gut microbiota. This trial is registered with ClinicalTrials.gov, NCT02725138.

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.

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.

Microbiome and cancer

The human microbiome constitutes a complex multikingdom community that symbiotically interacts with the host across multiple body sites. Host-microbiome interactions impact multiple physiological processes and a variety of multifactorial disease conditions. In the past decade, microbiome communities have been suggested to influence the development, progression, metastasis formation, and treatment response of multiple cancer types. While causal evidence of microbial impacts on cancer biology is only beginning to be unraveled, enhanced molecular understanding of such cancer-modulating interactions and impacts on cancer treatment are considered of major scientific importance and clinical relevance. In this review, we describe the molecular pathogenic mechanisms shared throughout microbial niches that contribute to the initiation and progression of cancer. We highlight advances, limitations, challenges, and prospects in understanding how the microbiome may causally impact cancer and its treatment responsiveness, and how microorganisms or their secreted bioactive metabolites may be potentially harnessed and targeted as precision cancer therapeutics.

Limosilactobacillus reuteri Strains as Adjuvants in the Management of Helicobacter pylori Infection

Helicobacter pylori (HP) is a Gram-negative bacterium which finds its suitable habitat in the stomach. The infection affects about half of the global population with high variability in prevalence among regions and for age. HP is the main causative agent of chronic active gastritis, peptic and duodenal ulcers, and may be the primary cause of gastric cancer or MALT lymphoma. Due to the high rate of failure of eradication therapy in various countries and the increase in antibiotic resistance reported in the literature, there is an ever wider need to seek alternative therapeutic treatments. Probiotics seem to be a promising solution. In particular, the Limosilactobacillus reuteri (L. reuteri) species is a Gram-positive bacterium and is commonly found in the microbiota of mammals. L. reuteri is able to survive the gastric acid environment and bile and to colonize the gastric mucosa. This species is able to inhibit the growth of several pathogenic bacteria through different mechanisms, keeping the homeostasis of the microbiota. In particular, it is able to secrete reuterin and reutericycline, substances that exhibit antimicrobial properties, among other molecules. Through the secretion of these and the formation of the biofilm, it has been found to strongly inhibit the growth of HP and, at higher concentrations, to kill it. Moreover, it reduces the expression of HP virulence factors. In clinical trials, L. reuteri has been shown to decrease HP load when used as a single treatment, but has not achieved statistical significance in curing infected patients. As an adjuvant of standard regimens with antibiotics and pump inhibitors, L. reuteri can be used not only to improve cure rates, but especially to decrease gastrointestinal symptoms, which are a common cause of lack of compliance and interruption of therapy, leading to new antibiotic resistance.

Helicobacter pylori: Perturbation and restoration of gut microbiome

Alternate remedies with natural products provides unlimited opportunities for new drug development. These can be either as pure compounds or as standardized set of compounds. The phytochemicals and secondary metabolites are in great demand for screening bioactive compounds and plays an important role towards drug development. Natural products have many advantages over to synthetic chemical drugs. Helicobacter pylori (H. pylori) a Gram-negative bacteria has been classified as Class I carcinogen by World Health Organization in 1994. Current treatment regimens for H. pylori is ‘triple therapy’ administrated for two weeks which includes a combination of two antibiotics like Amoxicillin and Clarithromycin and a proton pump inhibitor (PPI) like Lansoprazole, and for ‘quadruple therapy’ in addition to antibiotics and a PPI, Bismuth is used. Antibiotic resistance can be named as the main factor for failure of treatment of H. pylori infection. The need of the hour is to develop a herbal remedy that could combat the growth of H. pylori. Probiotics can also be used as ‘feasible’ tool for H. pylori infection management. Present review is an attempt to briefly discuss about the pathogenicity, genetic predisposition, perturbation of gut microbiota due to antibiotic treatment and restoration of healthy gut microbiota with phytochemicals and probiotics.

Interaction between Lactobacillus reuteri and periodontopathogenic bacteria using in vitro and in vivo (G. mellonella) approaches

Periodontitis is a multifactorial inflammatory disease, and the major cause of tooth loss in adults. New therapies have been proposed for its treatment, including the use of probiotics such as Lactobacillus reuteri. The objective of this study was to evaluate the antimicrobial effects of L. reuteri: live, heat-killed and culture filtrate (cell-free supernatant), on periodontopathogenic bacteria (Fusobacterium nucleatum and Aggregatibacter actinomycetemcomitans) in vitro, as well as the in vivo survival curve, hemocyte density and microbial recovery using Galleria mellonella. For in vitro assays, all preparations reduced colony forming units of F. nucleatum, while only live L. reuteri reduced the growth of A. actinomycetemcomitans. All treatments reduced periodontopathogenic bacteria growth in vivo. The treatment with the supernatant increased the survival of larvae infected with F. nucleatum more than the treatment with live L. reuteri, and none of the treatments altered the survival of A. actinomycetemcomitans-infected larvae. In addition, the treatment with L. reuteri preparations did not alter the hemocyte count of F. nucleatum- and A. actinomycetemcomitans-infected larvae. This study demonstrated that L. reuteri preparations exerted antimicrobial effects and increased the survival of G. mellonella infected by F. nucleatum, although only live L. reuteri was able to reduce the growth of A. actinomycetemcomitans in vitro.

Role of Sortase A in Lactobacillus gasseri Kx110A1 Adhesion to Gastric Epithelial Cells and Competitive Exclusion of Helicobacter pylori

We have previously shown that Lactobacillus gasseri Kx110A1, a human stomach isolate, can colonize mouse stomach and reduce the initial colonization of Helicobacter pylori. Here, we investigated the role of sortase-dependent proteins (SDPs) involved in these functions by the construction of a mutant for srtA, the gene encoding the housekeeping sortase that covalently anchors SDPs to the cell surface. The srtA mutant showed a decrease in hydrophobicity and autoaggregation under acidic conditions, indicating the effect of SDPs on cell surface properties. Correspondingly, the srtA mutant lost the capacity to adhere to gastric epithelial cells, thus resulting in an inability to provide a physical barrier to prevent H. pylori adherence. These results indicate that sortase A is a key determinant of the cell surface properties of L. gasseri Kx110A1 and contributes to Lactobacillus-mediated exclusion of H. pylori. Understanding the molecular mechanisms by which lactobacilli antagonize H. pylori might contribute to the development of novel therapeutic strategies that take advantage of health-promoting bacteria and reduce the burden of antibiotic resistance.

Probiotic therapy in Helicobacter pylori infection: a potential strategy against a serious pathogen?

Helicobacter pylori is a highly prevalent human pathogen responsible for chronic inflammation of the gastric tissues, gastroduodenal ulcers, and cancer. The treatment includes a pair of antibiotics with a proton pump inhibitor PPI. Despite the presence of different treatments, the infection rate is still increasing both in developed and developing states. The challenge of treatment failure is greatly due to the resistance of H. pylori to antibiotics and its side effects. Probiotics potential to cure H. pylori infection is well-documented. Probiotics combined with conventional treatment regime appear to have great potential in eradicating H. pylori infection, therefore, provide an excellent alternative approach to manage H. pylori load and its threatening disease outcome. Notably, anti-H. pylori activity of probiotics is strain specific,therefore establishing standard guidelines regarding the dose and formulation of individual strain is inevitable. This review is focused on probiotic's antagonism against H. pylori summarizing their three main potential aspects: their efficiency (i) as an alternative to H. pylori eradication treatment, (ii) as an adjunct to H. pylori eradication treatment and (iii) as a vaccine delivery vehicle.

The effect of Lactobacillus reuteri supplementation in Helicobacter pylori infection: a placebo-controlled, single-blind study

Background

Helicobacter pylori is the major cause of chronic gastritis, and considered as a risk factor for peptic ulcer and gastric cancer. The H. pylori standard antibiotic therapy fails in about 25–30% of cases, particularly because of the increasing occurrence of resistance to antibiotics. The aim of the current study was to investigate whether the strain Lactobacillus reuteri DSM17648 which has been previously shown to reduce Helicobacter pylori load additionally improves gastrointestinal symptoms in H. pylori positive subjects when used in a 28 days supplementation.

Methods

In a single-blinded, placebo controlled study 24 H. pylori-positive adults (13 females, 11 males; median age: 43.5) with mild dyspepsia (mean GSRS score: 11.82) received placebo for 28 days followed by Pylopass™ containing the L. reuteri DSM 17648 (2 × 10¹⁰ cells per day) for the following 28 days. After 28 days of Pylopass™ supplementation the change in H. pylori load was measured by ¹³C urea breath test (¹³C-UBT) and the change in symptoms were determined by the Gastrointestinal Symptom Rating Scale (GSRS). In addition, blood assessments were conducted to measure the physiological changes relevant in terms of safety.

Results

After a 28-day supplementation phase with Pylopass™ there was a trend for reduction of H. pylori load in 62.5% of the subjects and for the overall GSRS scores in 66.7% of subjects. The overall GSRS scores from baseline to day 56 following all 24 subjects undergoing the placebo phase followed by the Pylopass™ phase was significantly decreased (p = 0.005). The mean 13C-UBT δ value decreased by 22.5% during the Pylopass™ supplementation phase (− 3.14), while the mean 13C-UBT δ increased by 37.3% (+ 3.79) in the placebo phase. No side effects were reported in either study phase.

Conclusion

The results demonstrated that L. reuteri DSM17648 has the potential to suppress H. pylori infection, and may lead to an improvement of H. pylori-associated gastro intestinal symptoms. Further studies with adequate power should be performed.

Trial registration

Clinicaltrials.gov: NCT02051348 (January 30, 2014).

What Roles Do Probiotics Play in the Eradication of Helicobacter pylori? Current Knowledge and Ongoing Research

With the rising global prevalence of antibiotic resistance, the eradication rate of Helicobacter pylori (HP) is continuing to decrease. Probiotics are beneficial to human health and may be an adjunct therapy to increase the eradication rate of HP, lower treatment-associated side effects, and reduce HP-associated gastric inflammation. However, inconsistent test results have prevented conclusions about the therapeutic prowess of probiotics for HP. The mechanisms of actions of probiotics include the production of substances that inhibit or kill HP or compete with HP for the adhesion site on gastric epithelial cells. Probiotics can also reduce the release of inflammatory factors by regulating the local immune response of the host. We searched the available literature for full-length articles focusing on the role of probiotics in HP management. This review presents the latest advances in this area.

Considering gut microbiota disturbance in the management of Helicobacter pylori infection

Helicobacter pylori (Hp) infection produces drastic changes in the gastric microenvironment, which, in turn, influence the gastric microbiota composition and might be correlated with large intestinal microbiota changes. This excellent perturbing actor could trigger important modifications in the homeostatic functions exerted by gut commensals leading to a new gastrointestinal balance. At the same time, the therapeutic strategies used to eradicate Hp can modulate this physiological symbiosis, but can be also conversely affected by its properties. Area covered: The purpose of this review is to explore the reciprocal interplay between Hp infection and gut microbiota and analyze how microbial changes can influence the management of Hp eradication therapies. Expert commentary: While many studies have described Hp-dependent gut microbiota alterations, their clinical implications are only partially clear, as well as the mechanism of actions that sustain these processes. This represents a clear challenge for future research projects that will also need to understand which role is exerted by viruses, parasites, and yeasts.

Role of Lactobacillus reuteri in Human Health and Diseases

Lactobacillus reuteri (L. reuteri) is a well-studied probiotic bacterium that can colonize a large number of mammals. In humans, L. reuteri is found in different body sites, including the gastrointestinal tract, urinary tract, skin, and breast milk. The abundance of L. reuteri varies among different individuals. Several beneficial effects of L. reuteri have been noted. First, L. reuteri can produce antimicrobial molecules, such as organic acids, ethanol, and reuterin. Due to its antimicrobial activity, L. reuteri is able to inhibit the colonization of pathogenic microbes and remodel the commensal microbiota composition in the host. Second, L. reuteri can benefit the host immune system. For instance, some L. reuteri strains can reduce the production of pro-inflammatory cytokines while promoting regulatory T cell development and function. Third, bearing the ability to strengthen the intestinal barrier, the colonization of L. reuteri may decrease the microbial translocation from the gut lumen to the tissues. Microbial translocation across the intestinal epithelium has been hypothesized as an initiator of inflammation. Therefore, inflammatory diseases, including those located in the gut as well as in remote tissues, may be ameliorated by increasing the colonization of L. reuteri. Notably, the decrease in the abundance of L. reuteri in humans in the past decades is correlated with an increase in the incidences of inflammatory diseases over the same period of time. Direct supplementation or prebiotic modulation of L. reuteri may be an attractive preventive and/or therapeutic avenue against inflammatory diseases.

Probiotic monotherapy and Helicobacter pylori eradication: A systematic review with pooled-data analysis

AIM

To define probiotic monotherapy effect on Helicobacter pylori (H. pylori) status by performing a systematic review.

METHODS

Methods of analysis and inclusion criteria were based on PRISMA recommendations. Relevant publications were identified by searching PubMed, MEDLINE, Science Direct, and EMBASE. The end-point was to estimate eradication rate and urea breath test delta value before and after probiotic monotherapy across all studies and, overall, with a pooled data analysis. Adverse events of probiotic therapy were evaluated. The data were expressed as proportions/percentages, and 95%CIs were calculated. For continuous variables, we evaluated the weighted mean difference. Odd ratios (ORs) were calculated according to the Peto method for the comparison of eradication rates between probiotics and placebo.

RESULTS

Eleven studies were selected. Probiotics eradicated H. pylori in 50 out of 403 cases. The mean weighted eradication rate was 14% (95%CI: 2%-25%, P = 0.02). Lactobacilli eradicated the bacterium in 30 out of 235 patients, with a mean weighted rate of 16% (95%CI: 1%-31%). Saccharomyces boulardii achieved eradication in 6 out of 63 patients, with a pooled eradication rate of 12% (95%CI: 0%-29%). Multistrain combinations were effective in 14 out of 105 patients, with a pooled eradication rate of 14% (95%CI: 0%-43%). In the comparison of probiotics vs placebo, we found an OR of 7.91 in favor of probiotics (95%CI: 2.97-21.05, P < 0.001). Probiotics induced a mean reduction in delta values higher than placebo (8.61% with a 95%CI: 5.88-11.34, vs 0.19% for placebo, P < 0.001). Finally, no significant difference in adverse events was found between probiotics and placebo (OR = 1, 95%CI: 0.06-18.08).

CONCLUSION

Probiotics alone show a minimal effect on H. pylori clearance, thus suggesting a likely direct role.

The Esophageal and Gastric Microbiome in Health and Disease

The esophagus and stomach are host to their own population of bacteria, which differs in health and disease. Helicobacter pylori uniquely colonizes only gastric mucosa, but an increasing number of bacteria is now isolated from the gastric juice and gastric mucosa, including Lactobacillus. The presence of H pylori alters populations of other gastric bacteria with a marked reduction in diversity. Alterations in intragastric acidity may be the cause or the consequence of changes in the microbial populations of the stomach. Esophageal inflammation is associated with an altered microbiota in gastroesophageal reflux disease, Barrett's esophagus, eosinophilic esophagitis, and cancer.

Review of the role of probiotics in gastrointestinal diseases in adults

BACKGROUND

Probiotics may act as biological agents that modify the intestinal microbiota and certain cytokine profiles, which can lead to an improvement in certain gastrointestinal diseases.

OBJECTIVES

To conduct a review of the evidence of the role of probiotics in certain gastrointestinal diseases in adults.

SEARCH METHODS

Review conducted using appropriate descriptors, filters and limits in the PubMed database (MEDLINE).

SELECTION CRITERIA

The MeSH terms used were Probiotics [in the title] AND Gastrointestinal Diseases, with the following limits or filters: Types of study: Systematic Reviews, Meta-Analysis, Guideline, Practice Guideline, Consensus Development Conference (and Consensus Development Conference NIH), Randomized Controlled Trial, Controlled Clinical Trial and Clinical Trial; age: adults (19 or older); language: English and Spanish; in humans, and with at least one abstract.

DATA COLLECTION AND ANALYSIS

Full texts of all the Systematic Reviews and meta-analyses directly related to the review's objective were obtained, as well as the Randomised Controlled Trials of the studies that were considered relevant and of sufficient quality for this review.

MAIN RESULTS

Certain probiotics, different for each process, have proven to be effective and beneficial in cases of acute infectious diarrhoea, antibiotic-associated diarrhoea, Clostridium difficile-associated diarrhoea, pouchitis and Helicobacter pylori infection eradication.

AUTHORS' CONCLUSIONS

Although some probiotics have not demonstrated any benefit, there are certain gastrointestinal diseases in which the use of probiotics, true biological agents, can be recommended.

Potential role of probiotics in the management of gastric ulcer

Gastric ulcer is one of the most common chronic gastrointestinal diseases characterized by a significant defect in the mucosal barrier. Helicobacter pylori (H. pylori) infection and the frequent long-term use of non-steroidal anti-inflammatory drugs are major factors involved in gastric ulcer development. Acid inhibitors and antibiotics are commonly used to treat gastric ulcer. However, in the last few decades, the accumulating evidence for resistance to antibiotics and the side effects of antibiotics and acid inhibitors have drawn attention to the possible use of probiotics in the prevention and treatment of gastric ulcer. Probiotics are live microorganisms that when administered in adequate amounts confer health benefits on the host. Currently, the available experimental and clinical studies indicate that probiotics are promising for future applications in the management of gastric ulcers. This review aims to provide an overview of the general health benefits of probiotics on various systemic and gastrointestinal disorders with a special focus on gastric ulcer and the involved cellular and molecular mechanisms: i) Protection of gastric mucosal barrier; ii) upregulation of prostaglandins, mucus, growth factors and anti-inflammatory cytokines; iii) increased cell proliferation to apoptosis ratio; and iv) induction of angiogenesis. Finally, some of the available data on the possible use of probiotics in H. pylori eradication are discussed.

The Other Helicobacters

In the past year, a substantial number of (putative) novel Helicobacter species have been described, including Helicobacter himalayensis colonizing the Himalayan marmot and Helicobacter apodemus, colonizing the Korean striped field mouse. In addition, a putative novel gastric Helicobacter species was identified in wild gorillas and chimpanzees, for which the name "Candidatus H. homininae" was proposed. A high incidence of gastric non-H. pylori Helicobacter infection was described in China and multiple case reports have described the involvement of enterohepatic Helicobacter species, especially Helicobacter cinaedi, in a wide range of diseases. Several studies in rodent models further elucidated the mechanisms underlying the development of gastric mucosa-associated lymphoid tissue lymphoma during infection with gastric non-H. pylori Helicobacters. The effects of infection with gastric Helicobacters on the development of neuroinflammation were investigated and several enterohepatic Helicobacter species were shown to affect the composition of the gut microbiota, to influence vaccine efficiency as well as the progression of cancer in distant sites of the body.

Hypolipidemic effects and safety of Lactobacillus reuteri 263 in a hamster model of hyperlipidemia

We aimed to verify the beneficial effects of probiotic strain Lactobacillus reuteri 263 (Lr263) on hypolipidemic action in hamsters with hyperlipidemia induced by a 0.2% cholesterol and 10% lard diet (i.e., high-cholesterol diet (HCD)). Male Golden Syrian hamsters were randomly divided into two groups: normal (n = 8), standard diet (control), and experimental (n = 32), a HCD. After a two-week induction followed by a six-week supplementation with Lr263, the 32 hyperlipidemic hamsters were divided into four groups (n = 8 per group) to receive vehicle or Lr263 by oral gavage at 2.1, 4.2, or 10.5 × 10⁹ cells/kg/day for 6 weeks, designated the HCD, 1X, 2X and 5X groups, respectively. The efficacy and safety of Lr263 supplementation were evaluated by lipid profiles of serum, liver and feces and by clinical biochemistry and histopathology. HCD significantly increased serum levels of total cholesterol (TC), triacylglycerol (TG) cholesterol, high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C), LDL-C/HDL-C ratio, hepatic and fetal TC and TG levels, and degree of fatty liver as compared with controls. Lr263 supplementation dose dependently increased serum HDL-C level and decreased serum TC, TG, LDL-C levels, LDL-C/HDL-C ratio, hepatic TC and TG levels, and fecal TG level. In addition, Lr263 supplementation had few subchronic toxic effects. Lr263 could be a potential agent with a hypolipidemic pharmacological effect.

H. pylori and its modulation of gastrointestinal microbiota

The discovery of Helicobacter pylori (H. pylori) changed the dogma of the stomach as a sterile organ. H. pylori is an obligate pathogen in the human stomach and recognized as a definite carcinogen. Extensive research on the interaction of this bacterium with the gastric mucosa has been performed over the past three decades. The development of new nucleotide sequencing techniques and new biocomputational tools has opened the field for studying the diversity and complexity of the microbiome in the gastrointestinal tract independently of cultural methods. These techniques allow to better characterize further gastric bacteria. However, the differentiation of alive resident and transient microbes requires an analysis beyond the pure detection of bacterial genomic material applying a combination with metabolomic analyses. Currently, the interaction of gastric microbiota with each other, with H. pylori and with the host is addressed by extensive research. This review gives a concise overview on current knowledge on this topic.

Non-viable Lactobacillus reuteri DSMZ 17648 (Pylopass™) as a new approach to Helicobacter pylori control in humans

Prevalence of infections by Helicobacter pylori, a pathogen involved in a number of gastrointestinal diseases, remains high in developing countries. Management of infections by eradication is not always an option. Lactobacillus reuteri (L. reuteri) DSMZ17648 (Pylopass™/Lonza) specifically co-aggregates H. pylori in vitro and was shown to reduce ¹³C urea breath test in vivo. In this pilot study, we tried to replicate previous findings in an independent sample and to evaluate effects of spray-drying vs. freeze-drying of cultures. A single-blinded, placebo-controlled study was done in 22 H. pylori positive, asymptomatic adults. H. pylori levels were determined by ¹³C-urea-breath method after 14 days of supplementation, as well as after 6, 12, and 24 weeks follow-up. In the test group, but not in the placebo group, a significant reduction of H. pylori was observed. For the first time, spray-dried cells of L. reuteri DSMZ17648 have been used in a human study and results are in line with the first study results, supplementing with freeze-dried material. This is of special interest as spray-drying results in dead cell material, meaning that the effect of L. reuteri must be independent of its probiotic activity. These results confirm the potential of Pylopass™ as a novel way to reduce the load of H. pylori.