Effect of Lactobacillus GG supplementation on antibiotic-associated gastrointestinal side effects during Helicobacter pylori eradication therapy: 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.

Lactobacillus rhamnosus GG supplementation on eradication rate and dyspepsia in Helicobacter pylori infection treated with three-in-one bismuth quadruple therapy

Introduction

Helicobacter pylori (Hp)-related dyspepsia has been related to gastroduodenal dysbiosis. The role of probiotic supplementation in the clinical management of Hp infection has been the object of several studies in terms of improvement of efficacy and tolerability of eradication treatments but data on their effects on the outcomes of post-eradication dyspepsia are lacking. The aim of the present study was to evaluate the influence of Lactobacillus rhamnosus GG (LGG) supplementation on bismuth quadruple therapy (BQT) in the clinical management of Hp-related infection both in terms of efficacy and tolerability and persistence of post-treatment dyspepsia.

Methods

A total of 164 (121 women) Hp-positive adult patients were enrolled in this pilot study and assigned to two different treatment regimens: group A received BQT for 10 days (three capsules qid, IPP bid) and group B received BQT for 10 days in combination with 6 × 10⁹CFU LGG (ATCC53103) taken for 24 days (7 days before, 10 days during, and 7 days after therapy). Eradication was assessed after 45 days using the ¹³C-urea breath test (¹³C-UBT). Dyspepsia, distinguished into postprandial distress syndrome (PDS) and epigastric pain syndrome (EPS), was assessed at the time of enrollment and 6 months after eradication.

Results

Approximately 98 patients were enrolled in group A and 66 patients in group B. At the enrollment, dyspepsia was present in 76.5% of group A and 86.5% of group B. No significant differences were observed in eradication rate between the 2 groups, both in intention-to-treat (ITT) analysis (82.3 vs. 75.0%) and per-protocol (PP) analysis (95 vs. 96%), and in the presence of side effects during the treatment (70.6 vs. 65.4%). At 6 months after eradication of Hp infection, the persistence of dyspepsia was statistically higher in patients of group A than in group B (38.8 vs. 16.1%; p = 0.032). The positive influence of LGG supplementation in improving post-eradication dyspepsia resulted in statistically more effectiveness in PDS dyspepsia, whose remission was 41.7% in group A and 84% in group B patients (p = 0.011).

Conclusion

In conclusion, LGG supplementation during Hp eradication therapy, even if not affecting eradication rates and therapy-related side effects, significantly impacts the remission of dyspepsia.

Helicobacter pylori Eradication Therapy-associated Diarrhea

Eradication of Helicobacter pylori has contributed to the treatment of peptic ulcers and mucosa-associated lymphoid tissue lymphoma. Moreover, it has possibly decreased the prevalence of gastric cancer. However, eradication therapy is associated with various adverse effects, of which diarrhea is the most common. The incidence of diarrhea after eradication treatment varies from 8% to 48%. In particular, the incidence is higher in patients who receive first-line standard triple therapy compared with those who receive second-line therapy. Both antibiotics and proton pump inhibitors, components of eradication therapy, have short-term and long-term impacts on gut microbiota. The alterations of gut microbiota may not recover until 1 year after eradication therapy. Most cases of diarrhea that occur after eradication therapy are antibiotic-associated diarrhea caused by the destruction of the normal gut microbiota. In some cases, Clostridioides difficile-associated diarrhea occurs after eradication therapy. If bloody diarrhea occurs after eradication therapy and the Clostridioides difficile toxin is not detected, antibiotic-associated hemorrhagic colitis associated with Klebsiella oxytoca infection should be suspected. It is crucial to explain the possibility of diarrhea before initiating eradication therapy to increase compliance. Furthermore, probiotics may be administered to reduce diarrhea. If severe diarrhea or symptoms other than the usual antibiotic-associated diarrhea occur during or after eradication therapy, antibiotics should be discontinued. In addition, appropriate tests to determine the cause of diarrhea should be performed. This review summarizes the alteration of the gut microbiota, the causes of diarrhea after Helicobacter pylori eradication therapy, and its management.

Therapeutic Properties of Edible Mushrooms and Herbal Teas in Gut Microbiota Modulation

Edible mushrooms are functional foods and valuable but less exploited sources of biologically active compounds. Herbal teas are a range of products widely used due to the therapeutic properties that have been demonstrated by traditional medicine and a supplement in conventional therapies. Their interaction with the human microbiota is an aspect that must be researched, the therapeutic properties depending on the interaction with the microbiota and the consequent fermentative activity. Modulation processes result from the activity of, for example, phenolic acids, which are a major component and which have already demonstrated activity in combating oxidative stress. The aim of this mini-review is to highlight the essential aspects of modulating the microbiota using edible mushrooms and herbal teas. Although the phenolic pattern is different for edible mushrooms and herbal teas, certain non-phenolic compounds (polysaccharides and/or caffeine) are important in alleviating chronic diseases. These specific functional compounds have modulatory properties against oxidative stress, demonstrating health-beneficial effects in vitro and/or In vivo. Moreover, recent advances in improving human health via gut microbiota are presented. Plant-derived miRNAs from mushrooms and herbal teas were highlighted as a potential strategy for new therapeutic effects.

[Systematic review: clinical evidence of probiotics in the prevention of antibiotic-associated diarrhoea]

BACKGROUND

Antibiotic-associated diarrhoea (AAD) is the most common intestinal side effect of an antibiotic therapy. Various probiotics or probiotic combinations are often used preventively while taking antibiotics for the prevention of AAD.

METHOD

This review is based on a systematic literature research in MEDLINE and EMBASE. 7 probiotics are presented with regard to their effectiveness and evidence in the prevention of AAD. Only preparations classified by the World Gastroenerology Organization (WGO) with evidence levels 1-3 for the prevention of AAD were taken into account. 37 clinical studies, including 33 RCTs, were evaluated.

RESULTS

Saccharomyces (S.) boulardii CNCM I-745 is the most extensively studied probiotic regarding the prevention of AAD. It has shown evidence-based efficacy in all patient groups (outpatients and hospitalized children and adults). Lactobacillus rhamnosus GG also has a good evidence regarding the prevention of AAD in children and outpatient adults. The other probiotics and probiotic combinations evaluated in the present study only show efficacy in hospitalized patients or only show very limited evidence regarding their efficacy in the prevention of AAD due to the underlying study design or the small number of patients.

CONCLUSION

The effect of probiotics is strain-specific, no general statement can be made about the efficacy of probiotics in the prevention of AAD. In principle, it is advisable to select a probiotic with an evidence-based effect such as S. boulardii CNCM I-745 or Lactobacillus rhamnosus GG to prevent AAD.

Efficacy of Single-Strain Probiotics Versus Multi-Strain Mixtures: Systematic Review of Strain and Disease Specificity

The diversity of probiotic products makes choosing an appropriate probiotic challenging. One unanswered question is whether single-strain probiotics are more effective than multi-strain mixtures. The aim of this review is to account for both disease and strain specificity to determine whether single strains or multiple strains are equivalent or more effective. This literature review of randomized controlled trials from 1973 to 2019 was used to compare the pooled efficacy of trials with a single strain versus the probiotic mixture with same matched strain within the same type of disease indication. A total of 65 RCTs were included (41 with single strains, 22 multi-strain mixtures and 2 comparing single strain to mixture arms) for eight different disease indications (N = 10,863). Only three strains (L. rhamnosus GG, L. helveticus R52 and B. lactis Bb12) had corresponding trials with matching mixtures. Use of L. rhamnosus GG only was significantly more protective for necrotizing enterocolitis compared to two mixtures also containing different strains of B. lactis. The mixture of L. rhamnosus GG and B. lactis Bb12 was significantly more effective than L. rhamnosus GG alone for the eradication of H. pylori. In most cases, single strains were equivalent to mixtures. Choice of an appropriate probiotic should be based, not on the number of strains in the product, rather based on evidence-based trials of efficacy. In most cases, multi-strain mixtures were not significantly more effective than single-strain probiotics.

Meta-analysis of the efficacy of probiotic-supplemented therapy on the eradication of H. pylori and incidence of therapy-associated side effects

Traditional therapies for Helicobacter pylori (H. pylori) infection remain hindered by the antibiotic resistance of the pathogen and the poor therapeutic compliance of patients. To address these issues, probiotics have been added as an adjunctive therapy. This meta-analysis aimed to evaluate the efficacy of probiotic supplementation during standard therapy on the eradication rate of H. pylori infection and incidence of therapy-related side effects. Four online databases were searched for eligible studies without language restriction. Review Manager (REVMAN, Version 5.3) was used to perform all data analyses. Forty articles including 5792 patients met our criteria and were included in the analysis. Notably, probiotic supplementation improved the eradication rate by approximately 10% relative to the control group [odds ratio (OR), 1.94, 95% confidence interval (CI): 1.70-2.22, P < 0.00001]. The incidence of total side effects (OR, 0.56, 95% CI: 0.45-0.70, P < 0.00001) and individual symptoms (e.g., diarrhea, vomiting and nausea, constipation, epigastric pain, taste disturbance) also decreased significantly with probiotic supplementation. No other differences in side effects were observed between the experimental and control groups. Moreover, a longer duration (≥10 days) of probiotic treatment had positive effects on both eradication rate of H. pylori and incidence of overall side effects.

Polymeric carriers for enhanced delivery of probiotics

Probiotics are live microorganisms (usually bacteria), which are defined by their ability to confer health benefits to the host, if administered adequately. Probiotics are not only used as health supplements but have also been applied in various attempts to prevent and treat gastrointestinal (GI) and non-gastrointestinal diseases such as diarrhea, colon cancer, obesity, diabetes, and inflammation. One of the challenges in the use of probiotics is putative loss of viability by the time of administration. It can be due to procedures that the probiotic products go through during fabrication, storage, or administration. Biocompatible and biodegradable polymers with specific moieties or pH/enzyme sensitivity have shown great potential as carriers of the bacteria for 1) better viability, 2) longer storage times, 3) preservation from the aggressive environment in the stomach and 4) topographically targeted delivery of probiotics. In this review, we focus on polymeric carriers and the procedures applied for encapsulation of the probiotics into them. At the end, some novel methods for specific probiotic delivery, possibilities to improve the targeted delivery of probiotics and some challenges are discussed.

Efficacy of Lactobacillus-supplemented triple therapy for H. pylori eradication: A meta-analysis of randomized controlled trials

Aim

To assess the effect of Lactobacillus supplementation on Helicobacter pylori eradication rates and side effects of the triple therapy.

Methods

PubMed, Embase, Web of Science and Cochrane Library were searched for articles published up to July, 2019. Review Manager 5.3 and Stata 12.0 were used for statistical analyses.

Results

The initial database search resulted in 852 articles. Through exclusion and screening, 11 randomized controlled trials involving a total of 724 patients were finally included in this meta-analysis. The H. pylori elimination rate in the Lactobacillus supplement group was significantly higher than that in the control group (RR 1.16, 95% CI 1.08–1.25, P<0.0001). Subgroup analysis showed that the eradication rates were significantly enhanced in both adults and children group, and no significant difference was detected between Asia and Europe group. In addition, sub-analysis based on duration of Lactobacillus supplementation showed the pooled RRs in the long-term and short-term groups were 1.17 (95%CI 1.06–1.30) and 1.16 (95% CI 1.04–1.30), respectively. Regarding the Lactobacillus strains, the pooled RR was 1.33 (95% CI 1.10–1.62) in the L. casei group, 1.18 (95% CI 1.03–1.34) in the L. reuteri group while 1.02 (95% CI 0.87–1.21) in the Lactobacillus GG group. As for the total side effects, Lactobacillus supplementation significantly reduced the incidence of taste disturbance (RR = 0.36, 95% CI 0.17–0.74, P = 0.005).

Conclusions

Lactobacillus supplementation during the treatment of Helicobacter pylori infection can effectively improve the eradication rates, and reduce the incidence of therapy-related taste disturbance.

Efficacy and safety of probiotics in eradicating Helicobacter pylori: A network meta-analysis

BACKGROUND

Due to decreasing eradication rate and increasing side effects, probiotics have gradually become an important supplement to standard eradication regimens for Helicobacter pylori.

OBJECTIVE

To evaluate the effectiveness and safety of probiotics in facilitating the eradication of H pylori and to explore the best timing and duration of probiotic supplementation, use of eradication regimens, strains, locations, and common side effects.

METHODS

Eligible studies were retrieved from the PubMed, EMBASE, Cochrane Library, Web of Science, and CNKI databases, and we applied the Stata 12.0 software for the standard meta-analysis and network meta-analysis.

RESULTS

Forty eligible studies with 8924 patients were included in the analysis. We used a random-effects model (I = 52.1% and I = 81.4%) to analyze the eradication rate and the incidence of total side effects by intention to treat (ITT). Compared with the control group, a higher eradication rate (relative risk [RR] 1.140, 95% confidence interval (CI) 1.101-1.180, P < .001) and lower incidence of total side effects (RR 0.470, 95% CI 0.391-0.565, P < .001) were observed in the probiotic group. In the subgroup analysis, we evaluated the surface under the cumulative ranking curve scores for the before + same (75.2%), >2 weeks (92.6%), probiotic + quadruple regimen (99.9%), Lactobacillus (73.6%), multiple strains (72.1%), China (98.5%) groups. The rankings of common side effects are shown in Table 6. SUCRA scores for diarrhea (39.7%), abdominal pain (43.9%), nausea (78.8%), taste disturbance (99.6%), vomiting (7.1%), and constipation (30.9%) were reported. The consistency of all comparison groups was good.

CONCLUSIONS

Probiotics improved the eradication rate and reduced side effects when added to the treatments designed to eradicate H pylori. The use of probiotics before the eradication treatment and throughout the eradication treatment, and also the use of probiotics for more than 2 weeks, exerted better eradication effects. Probiotics combined with the bismuth quadruple regimen was the best combination. Lactobacillus and multiple strains were better choices of probiotic strains. The eradication effect observed in China was better than the effect observed in other countries.

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.

Helicobacter pylori Infection and Gastric Dysbiosis: Can Probiotics Administration Be Useful to Treat This Condition?

Helicobacter pylori (Hp) is responsible for one of the most common infections in the world. The prevalence exceeds 50% of the population in developing countries, and approximately one-third of the adults are colonized in North Europe and North America. It is considered a major pathogenic agent of chronic gastritis, peptic ulcer, atrophic gastritis, gastric cancer, and mucosa-associated lymphoid tissue lymphoma (MALT). Hp colonization modifies the composition of gastric microbiota that could drive the development of gastric disorders. Currently, an emerging problem in Hp treatment is represented by the increasing rate of antimicrobial therapy resistance. In this context, the search for adjuvant agents can be very useful to overcome this issue and probiotics administration can represent a valid option. The aim of this review is to describe the gastric microbiota changes during Hp colonization, the mechanisms of action, and a possible role of probiotics in the treatment of this infection.

The Probiotic Lactobacillus rhamnosus for Alleviation of Helicobacter pylori-Associated Gastric Pathology in East Africa

The probiotic Lactobacillus rhamnosus GG (LGG) can play a role in establishing a harmless relationship with Helicobacter pylori and reduce gastric pathology in East African populations. H. pylori has the ability to inhabit the surface of the mucous layer of the human stomach and duodenum. In the developing world, an estimated 51% of the population is carrier of H. pylori, while in some Western countries these numbers dropped below 20%, which is probably associated with improved sanitation and smaller family sizes. Colonization by H. pylori can be followed by inflammation of the gastric mucus layer, and is a risk factor in the development of atrophic gastritis, peptic ulcers and gastric cancer. Notwithstanding the higher prevalence of H. pylori carriers in developing countries, no equal overall increase in gastric pathology is found. This has been attributed to a less pro-inflammatory immune response to H. pylori in African compared to Caucasian populations. In addition, a relatively low exposure to other risk factors in certain African populations may play a role, including the use of non-steroidal anti-inflammatory drugs, smoking, and diets without certain protective factors. A novel approach to the reduction of H. pylori associated gastric pathology is found in the administration of the probiotic bacterium Lactobacillus rhamnosus yoba 2012 (LRY), the generic variant of LGG. This gastro-intestinal isolate inhibits H. pylori by competition for substrate and binding sites as well as production of antimicrobial compounds such as lactic acid. In addition, it attenuates the host's H. pylori-induced apoptosis and inflammation responses and stimulates angiogenesis in the gastric and duodenal epithelium. The probiotic LRY is not able to eradicate H. pylori completely, but its co-supplementation in antibiotic eradication therapy has been shown to relieve side effects of this therapy. In Uganda, unlike other African countries, gastric pathology is relatively common, presumably resulting from the lack of dietary protective factors in the traditional diet. Supplementation with LRY through local production of probiotic yogurt, could be a solution to establish a harmless relationship with H. pylori and reduce gastric pathology and subsequent eradication therapy treatment.

Strain-Specificity and Disease-Specificity of Probiotic Efficacy: A Systematic Review and Meta-Analysis

Background

As the use and diversity of probiotic products expands, the choice of an appropriate type of probiotic is challenging for both medical care professionals and the public alike. Two vital factors in choosing the appropriate probiotic are often ignored, namely, the probiotic strain-specificity and disease-specificity for efficacy. Reviews and meta-analyses often pool together different types of probiotics, resulting in misleading conclusions of efficacy.

Methods

A systematic review of the literature (1970-2017) assessing strain-specific and disease-specific probiotic efficacy was conducted. Trials were included for probiotics with an identifiable strain (either single strain or mixtures of strains) that had at least two randomized, controlled trials for each type of disease indication. The goal was to determine if probiotic strains have strain and/or disease-specific efficacy.

Results

We included 228 trials and found evidence for both strain specificity and disease specificity for the efficacy of specific probiotic strains. Significant efficacy evidence was found for 7 (70%) of probiotic strain(s) among four preventive indications and 11 (65%) probiotic strain(s) among five treatment indications. Strain-specific efficacy for preventing adult antibiotic-associated diarrhea was clearly demonstrated within the Lactobacillus species [e.g., by the mixture of Lactobacillus acidophilus CL1285, Lactobacillus casei LBC80R, and Lactobacillus rhamnosus CLR2 (Bio-K+^®), by L. casei DN114001 (Actimel^®) and by Lactobacillus reuteri 55730], while other Lactobacillus strains did not show efficacy. Significant disease-specific variations in efficacy was demonstrated by L. rhamnosus GG and Saccharomyces boulardii CNCM I-745, as well as other probiotic strains.

Conclusion

Strong evidence was found supporting the hypothesis that the efficacy of probiotics is both strain-specific and disease-specific. Clinical guidelines and meta-analyses need to recognize the importance of reporting outcomes by both specific strain(s) of probiotics and the type of disease. The clinical relevance of these findings indicates that health-care providers need to take these two factors into consideration when recommending the appropriate probiotic for their patient.

The effects of probiotics in lactose intolerance: A systematic review

Over 60 percent of the human population has a reduced ability to digest lactose due to low levels of lactase enzyme activity. Probiotics are live bacteria or yeast that supplements the gastrointestinal flora. Studies have shown that probiotics exhibit various health beneficial properties such as improvement of intestinal health, enhancement of the immune responses, and reduction of serum cholesterol. Accumulating evidence has shown that probiotic bacteria in fermented and unfermented milk products can be used to alleviate the clinical symptoms of lactose intolerance (LI). In this systematic review, the effectiveness of probiotics in the treatment of LI was evaluated using 15 randomized double-blind studies. Eight probiotic strains with the greatest number of proven benefits were studied. Results showed varying degrees of efficacy but an overall positive relationship between probiotics and lactose intolerance.

Anti-infective activities of lactobacillus strains in the human intestinal microbiota: from probiotics to gastrointestinal anti-infectious biotherapeutic agents

A vast and diverse array of microbial species displaying great phylogenic, genomic, and metabolic diversity have colonized the gastrointestinal tract. Resident microbes play a beneficial role by regulating the intestinal immune system, stimulating the maturation of host tissues, and playing a variety of roles in nutrition and in host resistance to gastric and enteric bacterial pathogens. The mechanisms by which the resident microbial species combat gastrointestinal pathogens are complex and include competitive metabolic interactions and the production of antimicrobial molecules. The human intestinal microbiota is a source from which Lactobacillus probiotic strains have often been isolated. Only six probiotic Lactobacillus strains isolated from human intestinal microbiota, i.e., L. rhamnosus GG, L. casei Shirota YIT9029, L. casei DN-114 001, L. johnsonii NCC 533, L. acidophilus LB, and L. reuteri DSM 17938, have been well characterized with regard to their potential antimicrobial effects against the major gastric and enteric bacterial pathogens and rotavirus. In this review, we describe the current knowledge concerning the experimental antibacterial activities, including antibiotic-like and cell-regulating activities, and therapeutic effects demonstrated in well-conducted, placebo-controlled, randomized clinical trials of these probiotic Lactobacillus strains. What is known about the antimicrobial activities supported by the molecules secreted by such probiotic Lactobacillus strains suggests that they constitute a promising new source for the development of innovative anti-infectious agents that act luminally and intracellularly in the gastrointestinal tract.

Probiotic supplementation does not improve eradication rate of Helicobacter pylori infection compared to placebo based on standard therapy: a meta-analysis

This meta-analysis included eligible randomized controlled trials (RCTs) with the aim of determining whether probiotic supplementation can improve H. pylori eradication rates. PUBMED, EBSCO, Web of Science, and Ovid databases were searched. We included RCTs that investigated the effect of combining probiotics, with or without a placebo, with standard therapy. A total of 21 RCTs that reported standard therapy plus probiotics were included. Compared to the placebo group, the probiotics group was 1.21(OR 1.21, 95% CI: 0.86, 1.69) and 1.28 (OR 1.28, 95% CI: 0.88, 1.86) times more likely to achieve eradication of H. pylori infection in intent-to-treat (ITT) analysis and per protocol (PP) analysis, respectively. Probiotics with triple therapy plus a 14-day course of treatment did not improve the eradication of H. pylori infection (OR 1.44, 95% CI: 0.87, 2.39) compared to the placebo. Moreover, the placebo plus standard therapy did not improve eradication rates compared to standard therapy alone (P = 0.816). However, probiotics did improve the adverse effects of diarrhea and nausea. These pooled data suggest that the use of probiotics plus standard therapy does not improve the eradication rate of H. pylori infection compared to the placebo.

Systematic review with meta-analysis: Lactobacillus rhamnosus GG in the prevention of antibiotic-associated diarrhoea in children and adults

BACKGROUND

The effects of probiotics are strain specific. The clinical effects of each strain need to be evaluated separately.

AIM

To evaluate the efficacy of Lactobacillus rhamnosus GG (LGG) in the prevention of antibiotic-associated diarrhoea (AAD) in children and adults.

METHODS

The Cochrane Library, MEDLINE, and EMBASE databases were searched up to July 2015, with no language restrictions, for randomised controlled trials (RCTs). Reference lists of reviews and included studies were examined. The quality of evidence (QoE) was assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) guidelines.

RESULTS

Twelve RCTs (1499 participants) were included. Treatment with LGG compared with placebo or no additional treatment reduced the risk of AAD in patients treated with antibiotics from 22.4% to 12.3% (11 RCTs, n = 1308, relative risk, RR: 0.49, 95% confidence interval, CI: 0.29-0.83, low QoE). However, when children and adults were evaluated separately, the difference was significant in children only (five RCTs, n = 445, RR 0.48, 95% CI 0.26-0.89; moderate QoE). In adults, the difference was not significant (six RCTs, n = 863, RR 0.48, 95% CI 0.20-1.15; low QoE), except for in a subset of patients receiving antibiotics as part of Helicobacter pylori eradication therapy (four RCTs, n = 280, RR 0.26, 95% CI 0.11-0.59; low QoE).

CONCLUSIONS

This meta-analysis shows that Lactobacillus rhamnosus GG is effective in preventing antibiotic-associated diarrhoea in children and adults treated with antibiotics for any reason. However, the quality of evidence is moderate to low.

Bacillus amyloliquefaciens as prophylactic treatment for Clostridium difficile-associated disease in a mouse model

BACKGROUND AND AIM

Probiotics might offer an attractive alternative for standard antibiotic therapy to treat Clostridium difficile infections (CDI). We specifically selected a Bacillus amyloliquefaciens strain for its high in vitro antibacterial activity against C. difficile and tested its efficacy to prevent CDI in a mouse model.

METHODS

B. amyloliquefaciens supernatant was tested against a large collection of C. difficile strains using an agar well diffusion test. B. amyloliquefaciens was orally administered to C57BL/6 mice in which CDI was induced using C. difficile VPI 10463, and its effect was compared with control mice receiving no treatment and mice receiving Saccharomyces boulardii. Mice were followed up daily for signs of disease including weight loss. At necropsy, the colon was collected and subjected to histopathological analysis. C. difficile toxin A/B levels and colon weight/length and colon/body weight ratios were calculated.

RESULTS

B. amyloliquefaciens supernatant was able to inhibit the growth of all C. difficile strains. Results of the in vivo trial indicated a significant weight loss for untreated and S. boulardii-treated mice as compared to B. amyloliquefaciens-treated mice. C. difficile toxin A and B levels were significantly higher for untreated and S. boulardii-treated mice than B. amyloliquefaciens-treated mice. A significantly lower degree of colon damage was detected for B. amyloliquefaciens-treated mice as compared to untreated and S. boulardii-treated mice, based on histopathological analysis, colon weight/length and colon/body weight ratios.

CONCLUSION

Administration of B. amyloliquefaciens was successful in preventing CDI in a mouse model.

Probiotics as adjunctive therapy for Helicobacter pylori infection: An overview of meta-analyses

AIM: To evaluate the relevant systematic reviews/meta-analyses that focused on probiotics as adjunctive therapy for Helicobacter pylori (H. pylori) infection.

METHODS: The systematic reviews/meta-analyses on probiotics as adjunctive therapy for H. pylori infection were searched in CBM, CNKI, Wanfang database, VIP Database, the Cochrane library, PubMed and Embase from inception to October 2014. Two reviewers screened the literature according to the inclusion criteria and extracted the data. The Overview Quality Assessment Questionnaire (OQAQ) was used to evaluate the quality of the included studies, and the GRADE system was used to evaluate the quality of evidence.

RESULTS: A total of 11 relevant meta-analyses were included, all of which evaluated the rate of H. pylori eradication and incidence of overall side effects (three evaluated the anti-H. pylori therapy-related side effects in detail). The mean OQAQ score was 3.82. Based on the GRADE system, the evidence quality was generally low.

CONCLUSION: Probiotics as adjunctive therapy for H. pylori infection have certain advantages, however, the overall quality of meta-analyses is poor, and the evidence level is low. Physicians should make an evidence-based decision according to the real condition.

Improved Helicobacter pylori Eradication Rate of Tailored Triple Therapy by Adding Lactobacillus delbrueckii and Streptococcus thermophilus in Northeast Region of Thailand: A Prospective Randomized Controlled Clinical Trial

Background and Aim. To evaluate the effect of Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus to Helicobacter pylori eradication in different periods of therapeutic protocol. Methods. Infected patients were randomized to one-week tailored triple therapy (esomeprazole 20 mg bid, clarithromycin 500 mg bid/metronidazole 400 mg tid if clarithromycin resistant, and amoxicillin 1000 mg bid) with placebo (group 1, n=100); one week of pretreatment with probiotics (group 2, n=100); and one week of pretreatment with probiotic followed by one week of the same probiotics after treatment (group 3, n=100). Result. PP analysis involved 292 patients, 98 in group 1, 97 in group 2, and 97 in group 3. Successful eradication was observed in 229 patients; by PP analysis, the eradication rates were significantly higher (P<0.01, 95% CI; 0.71–0.97) in group 2 and group 3 than group 1. ITT analysis eradication rates were significantly higher in group 2 and group 3 than group 1 (P<0.01 95% CI; 0.72–0.87), and there is no significant difference between the three groups (P=0.32) in terms of adverse events. Conclusion. Adding probiotics before or before and after tailored treatment can improve Helicobacter pylori eradication rates. This trial is registered with Thai Clinical Trials Registry number: TCTR20141209001.

Probiotics in Helicobacter pylori eradication therapy: A systematic review and meta-analysis

AIM: To summarize the evidence from randomized controlled trials (RCTs) regarding the effect of probiotics by using a meta-analytic approach.

METHODS: In July 2013, we searched PubMed, EMBASE, Ovid, the Cochrane Library, and three Chinese databases (Chinese Biomedical Literature Database, Chinese Medical Current Content, and Chinese Scientific Journals database) to identify relevant RCTs. We included RCTs investigating the effect of a combination of probiotics and standard therapy (probiotics group) with standard therapy alone (control group). Risk ratios (RRs) were used to measure the effect of probiotics plus standard therapy on Helicobacter pylori (H. pylori) eradication rates, adverse events, and patient compliance using a random-effect model.

RESULTS: We included data on 6997 participants from 45 RCTs, the overall eradication rates of the probiotic group and the control group were 82.31% and 72.08%, respectively. We noted that the use of probiotics plus standard therapy was associated with an increased eradication rate by per-protocol set analysis (RR = 1.11; 95%CI: 1.08-1.15; P < 0.001) or intention-to-treat analysis (RR = 1.13; 95%CI: 1.10-1.16; P < 0.001). Furthermore, the incidence of adverse events was 21.44% in the probiotics group and 36.27% in the control group, and it was found that the probiotics plus standard therapy significantly reduced the risk of adverse events (RR = 0.59; 95%CI: 0.48-0.71; P < 0.001), which demonstrated a favorable effect of probiotics in reducing adverse events associated with H. pylori eradication therapy. The specific reduction in adverse events ranged from 30% to 59%, and this reduction was statistically significant. Finally, probiotics plus standard therapy had little or no effect on patient compliance (RR = 0.98; 95%CI: 0.68-1.39; P = 0.889).

CONCLUSION: The use of probiotics plus standard therapy was associated with an increase in the H. pylori eradication rate, and a reduction in adverse events resulting from treatment in the general population. However, this therapy did not improve patient compliance.

Efficacy and safety of probiotics as adjuvant agents for Helicobacter pylori infection: A meta-analysis

The aim of the present study was to determine whether probiotics could help to improve the eradication rates and reduce the side effects associated with anti-Helicobacter pylori treatment, and to investigate the optimal time and duration of probiotic administration during the treatment, thus providing clinical practice guidelines for eradication success worldwide. By searching Pubmed, Embase, the Cochrane Central Register of Controlled Trials and the Science Citation Index, all the randomized controlled trials (RCTs) comparing probiotics as adjuvant agents of anti-H. pylori standard triple-therapy regimens with placebo or no treatment were selected. Statistical analysis was performed with the Comprehensive Meta Analysis Software. Subgroup, meta-regression and sensitivity analyses were also carried out. Twenty-one RCTs involving a total of 3,814 participants met the inclusion criteria. The pooled eradication rates of the probiotic group were 80.3% (1,709/2,128) by intention-to-treat (ITT) and 83.8% (1,709/2,039) by pro-protocol analyses; the pooled relative risk (RR) by ITT for probiotic supplementation versus treatment without probiotics was 1.12 [95% confidence interval (CI), 1.06-1.19]. A reduced risk of overall H. pylori therapy-related adverse effects was also found with probiotic supplementation (RR, 0.60; 95% CI, 0.40-0.91). The subgroup analyses showed that probiotic supplementation prior and subsequent to the treatment regimen both improved eradication rates for H. pylori infection. Furthermore, probiotic treatment lasting >2 weeks and including Lactobacillus or multiple probiotic strains significantly enhanced the efficacy. In conclusion, supplementation with probiotics for H. pylori eradication may be effective in increasing eradication rates and decreasing therapy-related side effects. Probiotic administration prior or subsequent to therapy and for a duration of >2 weeks may increase the eradication efficacy.

Stress-induced visceral pain: toward animal models of irritable-bowel syndrome and associated comorbidities

Visceral pain is a global term used to describe pain originating from the internal organs, which is distinct from somatic pain. It is a hallmark of functional gastrointestinal disorders such as irritable-bowel syndrome (IBS). Currently, the treatment strategies targeting visceral pain are unsatisfactory, with development of novel therapeutics hindered by a lack of detailed knowledge of the underlying mechanisms. Stress has long been implicated in the pathophysiology of visceral pain in both preclinical and clinical studies. Here, we discuss the complex etiology of visceral pain reviewing our current understanding in the context of the role of stress, gender, gut microbiota alterations, and immune functioning. Furthermore, we review the role of glutamate, GABA, and epigenetic mechanisms as possible therapeutic strategies for the treatment of visceral pain for which there is an unmet medical need. Moreover, we discuss the most widely described rodent models used to model visceral pain in the preclinical setting. The theory behind, and application of, animal models is key for both the understanding of underlying mechanisms and design of future therapeutic interventions. Taken together, it is apparent that stress-induced visceral pain and its psychiatric comorbidities, as typified by IBS, has a multifaceted etiology. Moreover, treatment strategies still lag far behind when compared to other pain modalities. The development of novel, effective, and specific therapeutics for the treatment of visceral pain has never been more pertinent.

The effect of probiotics supplementation on Helicobacter pylori eradication rates and side effects during eradication therapy: a meta-analysis

Background

Previous meta-analyses reported that probiotics improve the effectiveness of Helicobacter pylori (H. pylori) eradication during antibiotic therapy, while results regarding a possible reduction of side effects remained inconclusive. Moreover, the effectiveness of different strains of probiotics has not been studied so far. It is further conceivable that probiotics will produce additional effects only if antibiotics are relatively ineffective.

Methods

This meta-analysis includes eligible randomized controlled trials examining effects of probiotics supplementation on eradication rates (ER) and side effects, published up to May 2014. Sub-group analysis was performed to compare different probiotic strains and antibiotic therapies with different effectiveness in controls (ER <80% vs.>80%). Publication bias was assessed with funnel plots and Harbord's test. The quality of the trials was assessed with the Cochrane risk of bias tool.

Results

Thirty-three RCTs involving a total of 4459 patients met the inclusion criteria in case of eradication rates of which 20 assessed total side effects in addition. Overall, the pooled eradication rate in probiotics supplementation groups was significantly higher than in controls (ITT analysis: RR 1.122, 95% CI 1.086–1.159, PP analysis: RR 1.114, 95% CI 1.070–1.159). Sub group-analysis could, however, confirm this finding only for four individual strains (Lactobacillus acidophilus, Lactobacillus casei DN-114001, Lactobacillus gasseri, and Bifidobacterium infantis 2036) and for relatively ineffective antibiotic therapies. There was a significant difference between groups in the overall incidence of side effects (RR 0.735, 95% CI 0.598–0.902). This result was, however, only confirmed for non-blinded trials.

Conclusions

The pooled data suggest that supplementation with specific strains of probiotics compared with eradication therapy may be considered an option for increasing eradication rates, particularly when antibiotic therapies are relatively ineffective. The impact on side effects remains unclear and more high quality trials on specific probiotic strains and side effects are thus needed.

Probiotics, prebiotics and the gastrointestinal tract in health and disease

The microbiome located in the human gastrointestinal tract (GIT) comprises the largest community (diverse and dense) of bacteria, and in conjunction with a conducive internal milieu, promotes the development of regulated pro- and anti-inflammatory signals within the GIT that promotes immunological and metabolic tolerance. In addition, host-microbial interactions govern GIT inflammation and provide cues for upholding metabolic regulation in both the host and microbes. Failure to regulate inflammatory responses can increase the risk of developing inflammatory conditions in the GIT. Here, we review clinical studies regarding the efficacy of probiotics/prebiotics and the role they may have in restoring host metabolic homeostasis by rescuing the inflammatory response. The clinical studies reviewed included functional constipation, antibiotic-associated diarrhoea, Clostridium difficile diarrhoea, infectious diarrhoea/gastroenteritis, irritable bowel syndrome, inflammatory bowel diseases and necrotizing enterocolitis. We have demonstrated that there was an overall reduction in risk when probiotics were administered over placebo in the majority of GIT inflammatory conditions. The effect size of a cumulative reduction in relative risk for the GIT conditions/diseases investigated was 0.65 (0.61-0.70) (z = 13.3); p < 0.0001 that is an average reduction in risk of 35 % in favour of probiotics. We also progress a hypothesis that the GIT comprises numerous micro-axes (e.g. mucus secretion, Th1/Th2 balance) that are in operational homeostasis; hence probiotics and prebiotics may have a significant pharmacobiotic regulatory role in maintaining host GIT homeostasis in disease states partially through reactive oxygen species signalling.

Efficacy of fermented milk and whey proteins in Helicobacter pylori eradication: A review

Helicobacter pylori (H. pylori) eradication is considered a necessary step in the management of peptic ulcer disease, chronic gastritis, gastric adenocarcinoma and mucosa associated lymphoid tissue lymphoma. Standard triple therapy eradication regimens are inconvenient and achieve unpredictable and often poor results. Eradication rates are decreasing over time with increase in antibiotic resistance. Fermented milk and several of its component whey proteins have emerged as candidates for complementary therapy. In this context the current review seeks to summarize the current evidence available on their role in H. pylori eradication. Pertinent narrative/systematic reviews, clinical trials and laboratory studies on individual components including fermented milk, yogurt, whey proteins, lactoferrin, α-lactalbumin (α-LA), glycomacropeptide and immunoglobulin were comprehensively searched and retrieved from Medline, Embase, Scopus, Cochrane Controlled Trials Register and abstracts/proceedings of conferences up to May 2013. A preponderance of the evidence available on fermented milk-based probiotic preparations and bovine lactoferrin suggests a beneficial effect in Helicobacter eradication. Evidence for α-LA and immunoglobulins is promising while that for glycomacropeptide is preliminary and requires substantiation. The magnitude of the potential benefit documented so far is small and the precise clinical settings are ill defined. This restricts the potential use of this group as a complementary therapy in a nutraceutical setting hinging on better patient acceptability/compliance. Further work is necessary to identify the optimal substrate, fermentation process, dose and the ideal clinical setting (prevention/treatment, first line therapy/recurrence, symptomatic/asymptomatic, gastritis/ulcer diseases etc.). The potential of this group in high antibiotic resistance or treatment failure settings presents interesting possibilities and deserves further exploration.

Optimum duration of regimens for Helicobacter pylori eradication

BACKGROUND

The optimal duration for Helicobacter pylori (H. pylori) eradication therapy is controversial, with recommendations ranging from 7 to 14 days. Several systematic reviews have attempted to address this issue but have given conflicting results and limited their analysis to proton pump inhibitor (PPI), two antibiotics (PPI triple) therapy. We performed a systematic review and meta-analysis to investigate the optimal duration of multiple H. pylori eradication regimens.

OBJECTIVES

The primary objective was to assess the relative effectiveness of different durations (7, 10 or 14 days) of a variety of regimens for eradicating H. pylori. The primary outcome was H. pylori persistence. The secondary outcome was adverse events.

SEARCH METHODS

The Cochrane Library, MEDLINE, EMBASE, and CINAHL were searched up to December 2011 to identify eligible randomised controlled trials (RCTs). We also searched the proceedings of six conferences from 1995 to 2011, dissertations and theses, and grey literature. There were no language restrictions applied to any search.

SELECTION CRITERIA

Only parallel group RCTs assessing the efficacy of one to two weeks duration of first line H. pylori eradication regimens in adults were eligible. Within each regimen, the same combinations of drugs at the same dose were compared over different durations. Studies with at least two arms comparing 7, 10, or 14 days were eligible. Enrolled participants needed to be diagnosed with at least one positive test for H. pylori on the basis of a rapid urease test (RUT), histology, culture, urea breath test (UBT), or a stool antigen test (HpSA) before treatment. Eligible trials needed to confirm eradication of H. pylori as their primary outcome at least 28 days after completion of eradication treatment. Trials using only serology or a polymerase chain reaction (PCR) to determine H. pylori infection or eradication were excluded.

DATA COLLECTION AND ANALYSIS

Study eligibility and data extraction were performed by two independent review authors. Data analyses were performed within each type of intervention, for both primary and secondary outcomes. The relative risk (RR) and number needed to treat (NNT)/number needed to harm (NNTH) according to duration of therapy were calculated using the outcomes of H. pylori persistence and adverse events. A random-effects model was used. Subgroup analyses and sensitivity analyses were planned a priori.

MAIN RESULTS

In total, 75 studies met the inclusion criteria. Eight types of regimens were reported with at least two comparative eligible durations. They included: PPI + two antibiotics triple therapy (n = 59), PPI bismuth-based quadruple therapy (n = 6), PPI + three antibiotics quadruple therapy (n = 1), PPI dual therapy (n = 2), histamine H2-receptor antagonist (H₂RA) bismuth quadruple therapy (n = 3), H₂RA bismuth-based triple therapy (n = 2), H₂RA + two antibiotics triple therapy (n = 3), and bismuth + two antibiotics triple therapy (n = 2). Some studies provided data for more than one regimen or more than two durations.For the PPI triple therapy, 59 studies with five regimens were reported: PPI + clarithromycin + amoxicillin (PCA); PPI + clarithromycin + a nitroimidazole (PCN); PPI + amoxicillin + nitroimidazole (PAN); PPI + amoxicillin + a quinolone (PAQ); and PPI + amoxicillin + a nitrofuran (PANi). Regardless of type and dose of antibiotics, increased duration of PPI triple therapy from 7 to 14 days significantly increased the H. pylori eradication rate (45 studies, 72.9% versus 81.9%), the RR for H. pylori persistence was 0.66 (95% CI 0.60 to 0.74), NNT was 11 (95% CI 9 to 14). Significant effects were seen in the subgroup of PCA (34 studies, RR 0.65, 95% CI 0.57 to 0.75; NNT 12, 95% CI 9 to 16); PAN (10 studies, RR 0.67, 95% CI 0.52 to 0.86; NNT = 11, 95% CI 8 to 25); and in PAQ (2 studies, RR 0.37, 95% CI 0.16 to 0.83; NNT 3, 95% CI 2 to 10); but not in PCN triple therapy (4 studies, RR 0.87, 95% CI 0.71 to 1.07). Significantly increased eradication rates were also seen for PPI triple therapy with 10 versus 7 days (24 studies, 79.9% versus 75.7%; RR 0.80, 95% CI 0.72 to 0.89; NNT 21, 95% CI 15 to 38) and 14 versus 10 days (12 studies, 84.4% versus 78.5%; RR 0.72, 95% CI 0.58 to 0.90; NNT 17, 95% CI 11 to 46); especially in the subgroup of PAC for 10 versus 7 days (17 studies, RR 0.80, 95% CI 0.70 to 0.91) and for 14 versus 10 days (10 studies, RR 0.69, 95% CI 0.52 to 0.91). A trend towards increased H. pylori eradication rates was seen with increased duration of PCN for 10 versus 7 days, and of PAN for 10 versus 7 days and 14 versus 10 days, though this was not statistical significant. The proportion of patients with adverse events, defined by authors, was marginally significantly increased only between 7 days and 14 days (15.5% versus 19.4%; RR 1.21, 95% CI 1.06 to 1.37; NNTH 31, 95% CI 18 to 104) but not for other duration comparisons. The proportion of patients discontinuing treatment due to adverse events was not significantly different between treatment durations.Only limited data were reported for different durations of regimens other than PPI triple therapy. No significant difference of the eradication rate was seen for all regimens according to different durations except for H₂RA bismuth quadruple therapy, where a significantly higher eradication rate was seen for 14 days versus 7 days, however only one study reported outcome data.

AUTHORS' CONCLUSIONS

Increasing the duration of PPI-based triple therapy increases H. pylori eradication rates. For PCA, prolonging treatment duration from 7 to 10 or from 10 to 14 days is associated with a significantly higher eradication rate. The optimal duration of therapy for PCA and PAN is at least 14 days. More data are needed to confirm if there is any benefit of increasing the duration of therapy for PCN therapy. Information is limited for regimens other than PPI triple therapy; more studies are needed to draw meaningful conclusions for optimal duration of other H. pylori eradication regimens.

Who will win the race in childrens' oral cavities? Streptococcus mutans or beneficial lactic acid bacteria?

Adhesion to oral soft and hard tissue is crucial for bacterial colonisation in the mouth. The aim of this work was to select strains of oral lactic acid bacteria that could be used as probiotics for oral health. To this end, the adhesive properties of some lactic acid bacteria were investigated. Seventeen lactic acid bacteria including two Streptococcus mutans strains were isolated from the oral cavity of healthy children, while other strains were isolated from fermented meat products. The bacterial strains were applied to teeth surfaces covered with saliva or without saliva. A significant diversity in adhesion capacity to teeth surfaces among the lactic acid bacteria was observed. Lactic acid bacteria isolated from the oral cavity adhered the best to teeth surfaces covered with saliva, whereas lactic acid bacteria isolated from fermented meat samples adhered the best to tooth surface without saliva. All strains of lactic acid bacteria were able to reduce the number of S. mutans cells, in particular on saliva-coated tooth surface. Therefore, they might have potential as probiotics for the oral cavity.

Clinical application of probiotics in the treatment of Helicobacter pylori infection--a brief review

The role of probiotics in the treatment of gastrointestinal infections is increasingly being documented as an alternative or complement to antibiotics, with the potential to decrease the use of antibiotics or reduce their side effects. Although antibiotics-based Helicobacter pylori eradication treatment is 90% effective, it is expensive and causes antibiotic resistance associated with other adverse effects. Probiotics have an in vitro inhibitory effect on H. pylori. Animal studies demonstrated that probiotic treatment is effective in reducing H. pylori-associated gastric inflammation. About 12 human studies investigated the efficacy of combinations of antibiotics and probiotics, whereas 16 studies used probiotic alone as an alternative to antibiotics for the treatment of H. pylori infection. Most of the studies showed an improvement of H. pylori gastritis and decrease in H. pylori colonization after administration of probiotics. However, no study could demonstrate complete eradication of H. pylori infection by probiotic treatment. Probiotic combinations can reduce adverse effects induced by H. pylori eradication treatment and, thus, have beneficial effects in H. pylori-infected individuals. Long-term intakes of products containing probiotic strains may have a favorable effect on H. pylori infection in humans, particularly by reducing the risk of developing disorders associated with high degrees of gastric inflammation.

Protection and Restitution of Gut Barrier by Probiotics: Nutritional and Clinical Implications

Probiotics are beneficial bacteria present in various dietary components and many of these colonize in the human and animal intestine. In the gut probiotics help the host by assisting in maintenance of normal mucosal homeostasis. Probiotics not only help maintain normal function of the gut mucosa, but also protect mucosa from injurious factors such as toxins, allergens and pathogens. The beneficial effect of probiotics is mediated by multiple mechanisms, including cytoprotection, cell proliferation, cell migration, resistance to apoptosis, synthesis of proteins and gene expression. One of the important cytoprotective effects of probiotics in the intestinal mucosa is to strengthen the epithelial tight junctions and preservation of mucosal barrier function. Probiotics not only enhance barrier function by inducing synthesis and assembly of tight junction proteins, but also preventing disruption of tight junctions by injurious factors. Bioactive factors released by probiotics trigger activation of various cell signaling pathways that lead to strengthening of tight junctions and the barrier function. This article reviews and summarizes the current understanding of various probiotics that are involved in the protection of gut barrier function, highlights the cellular and molecular mechanisms involved in the protective effect and addresses the clinical implications of probiotic supplementation.

Meta-analysis: probiotics in antibiotic-associated diarrhoea

BACKGROUND

Diarrhoea is a common occurrence in association with antibiotic administration. Earlier studies and meta-analyses have suggested that probiotic administration reduces the incidence of antibiotic-associated diarrhoea (AAD).

AIM

To estimate the reduction in risk of AAD with administration of probiotics in randomised placebo-controlled trials and to identify factors associated with such reduction.

METHODS

Meta-analysis of randomised, double-blinded, placebo-controlled trials including patients treated with antibiotics and administered a probiotic for at least the duration of the antibiotic treatment. The outcome was incidence of diarrhoea irrespective of the presence of Clostridium difficile or the development of pseudomembranous colitis. Meta-analysis and meta-regression methods were used to synthesise data and to assess influence of: mean age, duration of antibiotics, risk of bias and incidence of diarrhoea in the placebo group on outcomes. Subgroup analyses explored effects of different probiotic species, patient populations and treatment indications.

RESULTS

A total of 34 studies were included with 4138 patients. The pooled relative risk (RR) for AAD in the probiotic group vs. placebo was 0.53 (95% CI 0.44-0.63), corresponding to a number needed to treat (NNT) of 8 (95% CI 7-11). The preventive effect of probiotics remained significant when grouped by probiotic species, population age group, relative duration of antibiotics and probiotics, study risk of bias and probiotic administered. The pooled RR for AAD during treatment for Helicobacter pylori (H. pylori) was 0.37 (95% CI 0.20-0.69), corresponding to a NNT of 5 (95% CI 4-10).

CONCLUSIONS

This updated meta-analysis confirms earlier results supporting the preventive effects of probiotics in AAD.

Impact of Lactobacillus reuteri Supplementation on Anti-Helicobacter pylori Levofloxacin-Based Second-Line Therapy

Introduction. Helicobacter pylori eradication therapy has the potential burden of antibiotic-associated gastrointestinal (GI) side effects. The occurrence of side effects is among the major drawbacks of such regimens. GI manifestations may be related to alterations in the intestinal microflora. Probiotics can prevent or reduce antibiotic-associated side effects and have an inhibitory effect on H. pylori. Methods. To define the efficacy of Lactobacillus reuteri supplementation in H. pylori eradication and in preventing GI-associated side effects during a second-line levofloxacin triple therapy. 90 H. pylori-positive patients receive for 7 days a second-line triple therapy with esomeprazole, levofloxacin, and amoxicillin with L. reuteri for 14 days (group 1) and without probiotic supplementation (group 2). Each subject received a validated questionnaire to record symptoms everyday for 4 weeks from the start of therapy. H. pylori status and side effects were assessed 6 weeks after treatment. Results. The eradication rate was significantly influenced by probiotic supplementation with L. reuteri (group 1: 36/45, 80%; group 2: 28/45 62%; P < 0.05). The incidence of nausea and diarrhoea in group 1 was significantly lower than that in group 2. Conclusion. In H. pylori-positive subjects L. reuteri supplementation increases the eradication rate while reducing the incidence of the most common side effects associated with antibiotic therapy in second-line treatment.

Preparation and characterization of a coacervate extended-release microparticulate delivery system for Lactobacillus rhamnosus

BACKGROUND

The purpose of this study was to develop a mucoadhesive coacervate microparticulate system to deliver viable Lactobacillus rhamnosus cells into the gut for an extended period of time while maintaining high numbers of viable cells within the formulation throughout its shelf-life and during gastrointestinal transit.

METHODS

Core coacervate mucoadhesive microparticles of L. rhamnosus were developed using several grades of hypromellose and were subsequently enteric-coated with hypromellose phthalate. Microparticles were evaluated for percent yield, entrapment efficiency, surface morphology, particle size, size distribution, zeta potential, flow properties, in vitro swelling, mucoadhesion properties, in vitro release profile and release kinetics, in vivo probiotic activity, and stability. The values for the kinetic constant and release exponent of model-dependent approaches, the difference factor, similarity factor, and Rescigno indices of model-independent approaches were determined for analyzing in vitro dissolution profiles.

RESULTS

Experimental microparticles of formulation batches were of spherical shape with percent yields of 41.24%-58.18%, entrapment efficiency 45.18%-64.16%, mean particle size 33.10-49.62 μm, and zeta potential around -11.5 mV, confirming adequate stability of L. rhamnosus at room temperature. The in vitro L. rhamnosus release profile follows zero-order kinetics and depends on the grade of hypromellose and the L. rhamnosus to hypromellose ratio.

CONCLUSION

Microparticles delivered L. rhamnosus in simulated intestinal conditions for an extended period, following zero-order kinetics, and exhibited appreciable mucoadhesion in simulated intestinal conditions.

Anti-Helicobacter pylori activity of fermented milk with lactic acid bacteria

BACKGROUND

Ten strains of lactic acid bacteria (LAB) were investigated for their anti-Helicobacter pylori effects. The bactericidal activity and organic acid content in spent culture supernatants (SCS) from fermented milk were measured. In addition, the exclusion effect of SCS against H. pylori infection of human gastric epithelial AGS cells was assayed.

RESULTS

Three LAB strains, LY1, LY5 and IF22, showed better anti-Helicobacter effects than the other strains. There were no significant differences in the bactericidal activity of LAB strains between original SCS, artificial SCS and SCS treated by heating or protease digestion. However, neutralised SCS lost this activity. These results suggest that the anti-H. pylori activity of SCS may be related to the concentration of organic acids and the pH value but not to protein components. In the AGS cell culture test, both fermented LY5-SCS and artificial LY5-SCS significantly reduced H. pylori infection and urease activity (P < 0.05).

CONCLUSION

In this study, in vitro methods were used to screen potential probiotics with anti-H. pylori activity. This may provide an excellent and rapid system for studying probiotics in the functional food and dairy industries.

Effects of multistrain probiotic-containing yogurt on second-line triple therapy for Helicobacter pylori infection

BACKGROUND AND AIMS

The adjuvant effects of probiotic-containing yogurt on second-line triple therapy for Helicobacter pylori (H. pylori) infection have not been evaluated.

METHODS

A total of 337 patients with persistent H. pylori infection, after first-line triple therapy, were randomly assigned to receive either triple therapy with (yogurt group, n=151) or without (control group, n=186) Will yogurt. Triple therapy consisted of 400 mg moxifloxacin q.d., 1000 mg amoxicillin b.i.d., and 20 mg esomeprazole b.i.d. for 14 days. Will yogurt contains Lactobacillus acidophilus, Lactobacillus casei, Bifidobacterium longum, and Streptococcus thermophilus. H. pylori eradication was evaluated by the (13)C-urea breath test, histology, or the rapid urease test.

RESULTS

The eradication rates by intention-to-treat analysis were 66.7% and 68.9% in the control and yogurt groups, respectively (P=0.667). The eradication rates by per-protocol analysis were 78.5% and 86% in the control and the yogurt groups, respectively (P=0.110). The adverse event rates were 25.3% and 28.5% in the control group and yogurt group, respectively (P=0.508).

CONCLUSIONS

The addition of yogurt containing probiotics to moxifloxacin-containing second-line treatment neither improved H. pylori eradication rates nor reduced the adverse events of treatment.

Effect of probiotic Lactobacillus (Lacidofil® cap) for the prevention of antibiotic-associated diarrhea: a prospective, randomized, double-blind, multicenter study

Antibiotic-associated diarrhea (AAD) is a common complication of antibiotic use. There is growing interest in probiotics for the treatment of AAD and Clostridium difficile infection because of the wide availability of probiotics. The aim of this multicenter, randomized, placebo-controlled, double-blind trial was to assess the efficacy of probiotic Lactobacillus (Lacidofil® cap) for the prevention of AAD in adults. From September 2008 to November 2009, a total of 214 patients with respiratory tract infection who had begun receiving antibiotics were randomized to receive Lactobacillus (Lacidofil® cap) or placebo for 14 days. Patients recorded bowel frequency and stool consistency daily for 14 days. The primary outcome was the proportion of patients who developed AAD within 14 days of enrollment. AAD developed in 4 (3.9%) of 103 patients in the Lactobacillus group and in 8 (7.2%) of 111 patients in the placebo group (P=0.44). However, the Lactobacillus group showed lower change in bowel frequency and consistency (50/103, 48.5%) than the placebo group (35/111, 31.5%) (P=0.01). Although the Lacidofil® cap does not reduce the rate of occurrence of AAD in adult patients with respiratory tract infection who have taken antibiotics, the Lactobacillus group maintains their bowel habits to a greater extent than the placebo group.

Role of Lactobacillus in the prevention of antibiotic-associated diarrhea: a meta-analysis

STUDY OBJECTIVE

To evaluate the efficacy of a Lactobacillus probiotic single-agent regimen in preventing antibiotic-associated diarrhea (AAD).

DESIGN

Meta-analysis of 10 randomized, blinded, placebo-controlled trials. Patients. A total of 1862 pediatric and adult patients who received a Lactobacillus single-agent regimen or placebo for the prevention of AAD.

MEASUREMENTS AND MAIN RESULTS

The MEDLINE, EMBASE, and Cochrane Central Register of Controlled Trials databases were searched from inception through May 2008 by two investigators independently using the following key words: probiotic, Lactobacillus, antibiotic-associated diarrhea. Full reports published in English were included if the studies were randomized, blinded, and placebo-controlled trials that evaluated the efficacy of Lactobacillus single-agent regimens versus placebo in the prevention of AAD. Bibliographies of recent review articles and systematic reviews were hand searched. Quality of the studies was assessed by using the Jadad scoring system. Number of subjects, age, Lactobacillus regimen, follow-up period, and occurrence of AAD were extracted into a standardized data collection form. Overall impact of Lactobacillus on AAD was compared with placebo by using a random-effects model. Ten studies with a total of 1862 patients (50.4% male) met all criteria. Six studies included patients aged 18 years or older, whereas four included patients younger than 18 years (range 2 wks-14 yrs). Jadad scores ranged from 2-5 (out of 5). The total daily dose of Lactobacillus ranged from 2 x 10(9)-4 x 10(10) colony-forming units and was administered throughout the entire antibiotic treatment (5-14 days) for all patients. The follow-up period varied from 2 days-3 months after the end of the probiotic regimen. The combined risk ratio (RR) of developing AAD was significantly lower with Lactobacillus compared with placebo (RR 0.35, 95% confidence interval [CI] 0.19-0.67). In a subgroup analysis, this held true for adults but not pediatric patients (RR 0.24, 95% CI 0.08-0.75 and RR 0.44, 95% CI 0.18-1.08, respectively).

CONCLUSION

Administration of a Lactobacillus single-agent regimen as a prophylactic agent during antibiotic treatment reduced the risk of developing AAD compared with placebo in adults but not pediatric patients.

Role of probiotics in pediatric patients with Helicobacter pylori infection: a comprehensive review of the literature

BACKGROUND

The current guidelines suggest the use of triple therapy as first choice treatment of Helicobacter pylori infection, although the eradication failure rate is more than 30%. Current interest in probiotics as therapeutic agents against H. pylori is stimulated not only by the clinical data showing efficacy of some probiotics in different gastrointestinal diseases but also by the increasing resistance of pathogenic bacteria to antibiotics, thus the interest for alternative therapies is a real actual topic.

AIM

To review in vitro and in vivo studies on the role of probiotics in H. pylori infection focusing on the paediatric literature.

MATERIALS AND METHODS

Pre-clinical and clinical paediatric studies in English assessing the role of probiotics in H. pylori infection identified by MEDLINE search (1950-2009) were reviewed.

RESULTS

In vitro studies demonstrated an inhibitory activity of probiotics on H. pylori growth and that this effect is extremely strain specific. Available data in children indicate that probiotics seems to be efficacious for the prevention of antibiotic associated side-effects, and might be of help for the prevention of H. pylori complications by decreasing H. pylori density and gastritis, and for the prevention of H. pylori colonization or re-infection by inhibiting adhesion to gastric epithelial cells. There is no clear evidence that probiotics may increase the H. pylori eradication rate.

CONCLUSION

Both in vitro and in vivo studies provide evidence that probiotics may represent a novel approach to the management of H. pylori infection.

Guidance for substantiating the evidence for beneficial effects of probiotics: prevention and management of infections by probiotics

The rationale for the use of probiotics in the management of infectious diseases is supported by their potential to influence and stabilize the composition of gut microbiota, enhance colonization resistance, and modulate immune function parameters. A literature review was conducted to determine the efficacy of using probiotics in selected infections: 1) infectious diarrhea in infants and children, 2) traveler's diarrhea, 3) necrotizing enterocolitis in infants, 4) Helicobacter pylori infection, 5) respiratory tract infections in adults and children, 6) ear, nose, and throat infections, and 7) infectious complications in surgical and critically ill patients. The different types of infections that have been subject to clinical studies with different probiotics obviously prevent any generic conclusions. Furthermore, the lack of consistency among studies focusing on 1 specific infection, in study design, applied probiotic strains, outcome parameters, and study population, along with the still limited number of studies, preclude clear and definite conclusions on the efficacy of probiotics and illustrate the need for better-aligned study designs and methodology. Exceptions were the management of infectious diarrhea in infants and traveler's diarrhea, antibiotic-associated diarrhea, and necrotizing enterocolitis. Sufficient consistent data exist for these applications to conclude that certain probiotics, under certain conditions, and in certain target populations, are beneficial in reducing the risk of infection. In addition, some evidence exists, although conclusions are premature, for the management of Helicobacter pylori infection and possible reduction of treatment side effects. Certain probiotics may also reduce the risk of various symptoms of respiratory tract infections in adults and children, including ear, nose, and throat infections, although data are currently far too limited to distill any clinical recommendations in this area. Positive but also negative results have been obtained in prevention of infectious complications in surgical and critically ill patients. For future studies it is recommended that researchers provide adequate power, identify pathogens, and report both clinical outcomes and immune biomarkers relating to putative underlying mechanisms.

Screening of the equine intestinal microflora for potential probiotic organisms

REASONS FOR PERFORMING STUDY

Probiotics have not been demonstrated to provide any beneficial health effects in horses, possibly because of improper selection of probiotic organisms. This study was designed to identify lactic acid bacteria of equine origin with predetermined beneficial properties which might make them useful as therapeutic probiotics.

HYPOTHESIS

A small percentage of lactic acid bacteria that are native to the intestinal tract of horses possess properties that may be useful in the treatment and/or prevention of gastrointestinal disease in horses.

METHODS

Faecal samples were collected from healthy mature horses and foals. Lactic acid bacteria were isolated and tested for the ability to grow in acid and bile environments, aerotolerance and in vitro inhibition of enteropathogens. One isolate that possessed these properties was administered orally to healthy mature horses and foals and gastrointestinal survival was assessed.

RESULTS

Of the 47 tested organisms, 18 were deemed to be adequately acid- and bile-tolerant. All were aerotolerant. Four organisms markedly inhibited Salmonella spp. One isolate, Lactobacillus pentosus WE7, was subjectively superior and chosen for further study. It was also inhibitory against E. coli, moderately inhibitory against S. zooepidemicus and C. difficile and mildly inhibitory against C. perfringens. After oral administration, this isolate was recovered from the faeces of 8/9 (89%) foals and 7/8 (87.5%) mature horses.

CONCLUSIONS

Lactobacillus pentosus WE7 possesses in vitro and in vivo properties that may be useful for the prevention and treatment of enteric disease in horses.

POTENTIAL RELEVANCE

The beneficial in vitro and in vivo properties that L. pentosus WE7 possesses indicate that randomised, blinded, placebo-controlled efficacy studies are warranted.

Meta-analysis: Lactobacillus containing quadruple therapy versus standard triple first-line therapy for Helicobacter pylori eradication

BACKGROUND

Recent evidence showed that Lactobacilli could exert an inhibitory effect on Helicobacter pylori both in vitro and in vivo models. To systematically evaluate whether adding Lactobacilli to H. pylori eradication regimens could improve eradication rates and reduce side effects during anti-H. pylori treatment.

MATERIALS AND METHODS

Eligible articles were identified by searches of electronic databases. We included all randomized trials comparing Lactobacilli supplementation to placebo or no treatment during anti-H. pylori regimens. Statistical analysis was performed with Review Manager 5.0.10. Subanalysis analysis was also performed.

RESULTS

We identified eight randomized trials (n = 1372). Pooled H. pylori eradication rates were 82.26% (95% CI = 78.01-86.51%) and 76.97% (95% CI = 73.11-80.83%) for patients with or without Lactobacilli by intention-to-treat analysis, respectively, the odds ratio (OR) was 1.78 (95% CI = 1.21-2.62). The occurrence of total side effects had no significant difference and were 30.84% (95% CI = 24.82-36.86%) and 42.24% (95% CI = 35.89%-48.59%) for two groups, the summary OR was 0.49 (95% CI = 0.24-1.02); However, Lactobacilli supplementation group had lower occurrence of diarrhoea, bloating and taste disturbance.

CONCLUSIONS

Our review suggests that supplementation with Lactobacilli could be effective in increasing eradication rates of anti-H. pylori therapy for first-treated patients. Furthermore, Lactobacilli showed a positive impact on some H. pylori therapy-related side effects.