Probiotics (Lactobacillus gasseri KS-13, Bifidobacterium bifidum G9-1, and Bifidobacterium longum MM-2) improve rhinoconjunctivitis-specific quality of life in individuals with seasonal allergies: a double-blind, placebo-controlled, randomized trial

Bifidobacteria in disease: from head to toe

Bifidobacteria as a strictly anaerobic gram-positive bacteria, is widely distributed in the intestine, vagina and oral cavity, and is one of the first gut flora to colonize the early stages of life. Intestinal flora is closely related to health, and dysbiosis of intestinal flora, especially Bifidobacteria, has been found in a variety of diseases. Numerous studies have shown that in addition to maintaining intestinal homeostasis, Bifidobacteria may be involved in diseases covering all parts of the body, including the nervous system, respiratory system, genitourinary system and so on. This review collects evidence for the variation of Bifidobacteria in typical diseases among various systems, provides mild and effective therapeutic options for those diseases that are difficult to cure, and moves Bifidobacteria from basic research to further clinical applications.

HMGN2 and Histone H1.2: potential targets of a novel probiotic mixture for seasonal allergic rhinitis

Background

Allergic rhinitis (AR) is a common nasal inflammatory disorder that severely affects an individual's quality of life (QoL) and poses a heavy financial burden. In addition to routine treatments, probiotic intervention has emerged as a promising strategy for preventing and alleviating allergic diseases. The main objective of this study was to determine the effect of a novel multi-strain probiotic mixture on AR symptoms and investigate potential targets underlying the probiotic intervention.

Methods

A randomized, double-blind, placebo-controlled clinical study was conducted on AR patients who were allergic to autumnal pollens (n = 31). Placebo or a novel probiotic mixture, composed of Lactobacillus rhamnosus (L. rhamnosus) HN001, L. acidophilus NCFM, Bifidobacterium lactis (B. lactis) Bi-07, L. paracasei LPC-37, and L. reuteri LE16, was administered after 2 months. The therapeutic efficacy was evaluated by a symptom assessment scale. Before and during the pollen season, blood samples were collected, and peripheral blood mononuclear cells (PBMCs) were isolated for further tandem mass tags (TMTs)-based quantitative proteomic analyses. Potential targets and underlying pathological pathways were explored using bioinformatics methods.

Results

During the pollen season, the rhinoconjunctivitis symptom score of participants who were administered probiotics (probiotic group, n = 15) was significantly lower than those administered placebo (placebo group, n = 15) (P = 0.037). The proteomic analyses identified 60 differentially expressed proteins (DEPs) in the placebo group, and subsequent enrichment analyses enriched a series of pathways and biological processes, including signaling pathways of inflammation, coagulation cascade, lipid, carbohydrate and amino acid metabolic pathways, and transcription and translation processes. Least Absolute Shrinkage and Selection Operator (LASSO) regression extracted five main elements, namely, GSTO1, ATP2A2, MCM7, PROS1, and TRIM58, as signature proteins. A total of 17 DEPs were identified in the probiotic group, and there was no pathway enriched. Comparison of DEPs in the two groups revealed that the expression levels of the high-mobility group nucleosome-binding domain-containing protein 2 (HMGN2) and Histone H1.2 presented an opposite trend with different interventions.

Conclusion

Our data showed that AR symptoms alleviated after treatment with the novel multi-strain probiotic mixture, and the proteomic analyses suggested that HMGN2 and Histone H1.2 might be targets of probiotic intervention for seasonal AR.

The role of synbiotics as adjunctive agents in the treatment of allergic rhinitis: A randomized controlled trial

Introduction

Allergic rhinitis (AR) is a prevalent chronic disease affecting a significant portion of the global population. The substantial economic burden associated with treating AR necessitates the exploration of alternative therapies. Probiotics have gained attention due to their availability, minimal adverse effects, and cost-effectiveness. The present study aims to investigate the role of synbiotics as adjunctive agents in the treatment of AR when added to standard treatment.

Method

Thirty patients with persistent allergic rhinitis (PAR) were randomly assigned to receive routine diet therapy plus synbiotics or routine diet therapy plus placebo per day for 4 months. The data analysis was conducted using SPSS Version 20.

Result

This study revealed a notable difference in immunoglobulin (Ig)E levels between the placebo and synbiotics groups (p = 0.035) following the intervention. Although a statistically significant difference (p = 0.039) was observed in the changes before and after the intervention (synbiotics and placebo) in the SNOT22 questionnaire, this finding was not observed for the MiniRQLQ questionnaire. For the MiniRQLQ questionnaire, the within-group analysis showed significant changes in activity variables (p = 0.023), ocular symptoms (p = 0.036), and practical problems (p = 0.043) exclusively in the synbiotics group. Additionally, changes in nasal symptoms were observed in both synbiotics (p = 0.006) and placebo (p = 0.007) groups.

Conclusion

This study suggests that synbiotics supplementation for 4 months can impact IgE levels compared with placebo in individuals with PAR, while also exhibiting positive effects on symptomology.

Assessing Gastrointestinal Tolerance in Healthy Adults: Reliability and Validity of a Weekly Questionnaire

When examining gastrointestinal tolerance to nondigestible carbohydrates, a weekly vs. daily symptoms questionnaire may lessen participant burden. This secondary analysis examined the reliability and validity of the Gastrointestinal Symptom Rating Scale (GSRS) in healthy adults. The internal consistency reliability of the GSRS syndromes and a daily questionnaire (DQ) comparator were determined. The GSRS syndromes prediction of slow transit stool form was assessed by ROC analysis. The DQ (α = 0.76) and GSRS syndromes of constipation (α = 0.73; ω = 0.74), and diarrhea (α = 0.76; ω = 0.77) exhibited acceptable reliability, as did the GSRS overall (α = 0.76; ω = 0.87) but not the syndromes of abdominal pain (α = 0.54; ω = 0.54), reflux (α = 0.69; ω = 0.67), or indigestion (α = 0.64; ω = 0.67). The GSRS syndromes predicted slow transit stools (AUC = 0.855), and the GSRS items of stomach pain, nausea, flatus, constipation, and diarrhea were moderately correlated (ρ = 0.55-0.64; P < 0.001) with the corresponding DQ items. The GSRS may be useful to assess gastrointestinal tolerance and efficacy of nondigestible carbohydrates given its performance at predicting slow transit stools, suggestive of constipation.

Efficacy and safety of gastrointestinal microbiome supplementation for allergic rhinitis: A systematic review and meta-analysis with trial sequential analysis

BACKGROUND

Allergic rhinitis (AR) is a non-infective chronic inflammatory disease of nasal mucosa.

PURPOSE

To evaluate the efficacy and safety of gastrointestinal microbiome supplementation (GMS) for patients with allergic rhinitis (AR), concerning improvement on symptoms and signs, laboratory outcomes, quality of life, and medication scores.

METHODS

Five English databases were searched up to Dec 12th, 2022. Probiotics, prebiotics, and synbiotics were main therapies or adjuvants in experimental groups. Systematic reviews and meta-analyses were conducted based on the Cochrane systematic review method by using RevMan 5.4 Software, with meta-influence analyses, subgroup-analyses, meta-regression, and publication bias performed for exploration of heterogeneity by Stata V.14. Trial sequential analyses were performed by TSA 0.9, and quality of the results was accessed through the GRADE-pro GDT.

RESULTS

Finally, extracted from 53 articles, 65 RCTs involving 3,634 participants with sound worldwide representativeness were included. Primary results showed better improvement in GMS groups on TNSS (WMD=1.05, P for WMD=0.004, 95%CI:0.34 to 1.76), overall nasal condition (WMD=1.25, P for WMD<0.001, 95%CI:0.90 to 1.61), overall quality of life (WMD=6.16, P for WMD<0.001, 95%CI:4.92 to 7.40) and medication score (WMD=0.42, P for WMD=0.42, 95%CI:-0.06 to 0.90).However, GMS groups were inferior than the controls concerning reduction on serum total IgE (WMD=-1.81) and ratios of serum Th1/Th2 (WMD=-1.06). Meta-regressions suggested significant (p<0.05) variations of the effects in some comparisons. In addition, results of sub-group analyses firstly revealed potential influence between final results and the variables above. Instantly after intervention, the GRADE levels of evidence were sound, including "High ⨁⨁⨁⨁" in 10, "Moderate ⨁⨁⨁◯" in 33, and "Low ⨁⨁◯◯" in nine comparisons. However, overall certainties decreased obviously during follow-ups.

CONCLUSION

Overall, our pooled results firstly revealed that GMS yielded acceptable benefits for patients with AR compared with controls with sound certainties, after balancing the benefits and harms.

TFOS Lifestyle: Impact of nutrition on the ocular surface

Nutrients, required by human bodies to perform life-sustaining functions, are obtained from the diet. They are broadly classified into macronutrients (carbohydrates, lipids, and proteins), micronutrients (vitamins and minerals) and water. All nutrients serve as a source of energy, provide structural support to the body and/or regulate the chemical processes of the body. Food and drinks also consist of non-nutrients that may be beneficial (e.g., antioxidants) or harmful (e.g., dyes or preservatives added to processed foods) to the body and the ocular surface. There is also a complex interplay between systemic disorders and an individual's nutritional status. Changes in the gut microbiome may lead to alterations at the ocular surface. Poor nutrition may exacerbate select systemic conditions. Similarly, certain systemic conditions may affect the uptake, processing and distribution of nutrients by the body. These disorders may lead to deficiencies in micro- and macro-nutrients that are important in maintaining ocular surface health. Medications used to treat these conditions may also cause ocular surface changes. The prevalence of nutrition-related chronic diseases is climbing worldwide. This report sought to review the evidence supporting the impact of nutrition on the ocular surface, either directly or as a consequence of the chronic diseases that result. To address a key question, a systematic review investigated the effects of intentional food restriction on ocular surface health; of the 25 included studies, most investigated Ramadan fasting (56%), followed by bariatric surgery (16%), anorexia nervosa (16%), but none were judged to be of high quality, with no randomized-controlled trials.

Assessment of a Multispecies Probiotic Supplement for Relief of Seasonal Allergic Rhinitis: A Randomized Double-Blind Placebo-Controlled Trial

Background: Early phase clinical research provided initial support for the use of a multispecies probiotic supplement to improve quality of life (QoL) in adults with seasonal allergic rhinitis (AR) and reduce the use of AR symptom relieving medication. This study aimed to confirm these early phase findings in a double-blind randomized placebo-controlled trial. Methods: Individuals, aged 18-65 years, with a minimum 2-year history of AR, moderate-to-severe AR symptoms, and a positive radio-allergosorbent test to Bermuda (Couch) Grass were randomized to receive either a multispecies probiotic supplement (total colony-forming units 4 × 10⁹/day) or placebo twice daily for 8 weeks. A mini-rhinoconjunctivitis quality of life questionnaire (mRQLQ) scale was administered at screening, days 0, 28, and 56. The proportion of participants with a >0.7 improvement in mRQLQ was the primary outcome. Participants also completed a daily symptom and medication diary during the supplementation period. Results: There were 165 participants randomized, with 142 included in the primary outcome analysis. The percentage of participants meeting the threshold for a clinically meaningful reduction in the mRQLQ from days 0 to 56 was not significantly different between groups (61% vs. 62%, p = 0.90). However, 76 participants had a clinically meaningful improvement in QoL (decrease in mRQLQ >0.7) prior to the start of supplementation (screening to day 0). Conclusion: Changes in self-reported QoL and other disease severity metrics between screening and the start of supplementation limited the ability to discern an effect of supplementation and highlight the need for adaptive clinical trial designs in allergy research. Clinical Trial Registration: The trial was registered with the Australia and New Zealand Clinical Trials Registry (ACTRN12619001319167).

Enhancing Regulatory T Cells to Treat Inflammatory and Autoimmune Diseases

Regulatory T cells (Tregs) control immune responses and are essential to maintain immune homeostasis and self-tolerance. Hence, it is no coincidence that autoimmune and chronic inflammatory disorders are associated with defects in Tregs. These diseases have currently no cure and are treated with palliative drugs such as immunosuppressant and immunomodulatory agents. Thereby, there is a great interest in developing medical interventions against these diseases based on enhancing Treg cell function and numbers. Here, we give an overview of Treg cell ontogeny and function, paying particular attention to mucosal Tregs. We review some notable approaches to enhance immunomodulation by Tregs with therapeutic purposes including adoptive Treg cell transfer therapy and discuss relevant clinical trials for inflammatory bowel disease. We next introduce ways to expand mucosal Tregs in vivo using microbiota and dietary products that have been the focus of clinical trials in various autoimmune and chronic-inflammatory diseases.

A Comparative Study to Assess the Add on Effects of Probiotic in Allergic Rhinitis Patients in a Tertiary Care Hospital

Probiotic intervention may have a promising role in the prevention of AR, in preventing allergic diseases including AR. Probiotics can exert beneficial effects on the host through distinct cellular and molecular pathways, these mechanisms of action may vary from one kind of probiotic to another for the same immune response and may be regulated by a combination of several events. Material and methods- Research site-Tertiary Care Government Hospital and Medical College in a major metropolitan city.TYPE OF STUDY-Prospective comparative Study.No. of Subjects -100 cases.Study Duration-Duration for collection of data-24 months.Sample size -100 patientsData Collection:Was collected from data of case proforma of all patients.Mode of Selection -Patients presenting in Out Patient Department (OPD)and In PatientDepartment(IPD) who meet the inclusion criteria and who consent to be a part of the study.Results-Significant difference was found in 12 weeks of treatment among group A and group B. Mild symptoms were seen more after 12 weeks in group B while severity of symptom reduction was less in group A as compared to group B in 12 weeks of treatment.Conclusion Probiotic intervention may have a promising role in the prevention of AR, in preventing allergic diseases including AR.Probiotics can exert beneficial effects on the host through distinct cellular and molecular pathways, these mechanisms of action may vary from one kind of probiotic to another for the same immune response and may be regulated by a combination of several events. Thus making probiotics' mechanism of action a challenging, complex, and fertile area for investigation. Probiotics appear to prevent allergy recurrences, alleviate the severity of symptoms and improve the quality of life of patients with allergic rhinitis.

International consensus statement on allergy and rhinology: Allergic rhinitis - 2023

BACKGROUND

In the 5 years that have passed since the publication of the 2018 International Consensus Statement on Allergy and Rhinology: Allergic Rhinitis (ICAR-Allergic Rhinitis 2018), the literature has expanded substantially. The ICAR-Allergic Rhinitis 2023 update presents 144 individual topics on allergic rhinitis (AR), expanded by over 40 topics from the 2018 document. Originally presented topics from 2018 have also been reviewed and updated. The executive summary highlights key evidence-based findings and recommendation from the full document.

METHODS

ICAR-Allergic Rhinitis 2023 employed established evidence-based review with recommendation (EBRR) methodology to individually evaluate each topic. Stepwise iterative peer review and consensus was performed for each topic. The final document was then collated and includes the results of this work.

RESULTS

ICAR-Allergic Rhinitis 2023 includes 10 major content areas and 144 individual topics related to AR. For a substantial proportion of topics included, an aggregate grade of evidence is presented, which is determined by collating the levels of evidence for each available study identified in the literature. For topics in which a diagnostic or therapeutic intervention is considered, a recommendation summary is presented, which considers the aggregate grade of evidence, benefit, harm, and cost.

CONCLUSION

The ICAR-Allergic Rhinitis 2023 update provides a comprehensive evaluation of AR and the currently available evidence. It is this evidence that contributes to our current knowledge base and recommendations for patient evaluation and treatment.

Efficacy of Bifidobacterium longum alone or in multi-strain probiotic formulations during early life and beyond

The significance of Bifidobacterium to human health can be appreciated from its early colonization of the neonatal gut, where Bifidobacterium longum represents the most abundant species. While its relative abundance declines with age, it is further reduced in several diseases. Research into the beneficial properties of B. longum has unveiled a range of mechanisms, including the production of bioactive molecules, such as short-chain fatty acids, polysaccharides, and serine protease inhibitors. From its intestinal niche, B. longum can have far-reaching effects in the body influencing immune responses in the lungs and even skin, as well as influencing brain activity. In this review, we present the biological and clinical impacts of this species on a range of human conditions beginning in neonatal life and beyond. The available scientific evidence reveals a strong rationale for continued research and further clinical trials that investigate the ability of B. longum to treat or prevent a range of diseases across the human lifespan.

Probiotics and Postbiotics as the Functional Food Components Affecting the Immune Response

The food market is one of the most innovative segments of the world economy. Recently, among consumers there is a forming trend of a healthier lifestyle and interest in functional foods. Products with positive health properties are a good source of nutrients for consumers' nutritional needs and reduce the risk of metabolic diseases such as diabetes, atherosclerosis, or obesity. They also seem to boost the immune system. One of the types of functional food is "probiotic products", which contain viable microorganisms with beneficial health properties. However, due to some technical difficulties in their development and marketing, a new alternative has started to be sought. Many scientific studies also point to the possibility of positive effects on human health, the so-called "postbiotics", the characteristic metabolites of the microbiome. Both immunobiotics and post-immunobiotics are the food components that affect the immune response in two ways: as inhibition (suppressing allergies and inflammation) or as an enhancement (providing host defenses against infection). This work's aim was to conduct a literature review of the possibilities of using probiotics and postbiotics as the functional food components affecting the immune response, with an emphasis on the most recently published works.

Dairy-Based Probiotic-Fermented Functional Foods: An Update on Their Health-Promoting Properties

Numerous studies have shown a link between the consumption of fermented dairy foods and improved health outcomes. Since the early 2000s, especially probiotic-based fermented functional foods, have had a revival in popularity, mostly as a consequence of claims made about their health benefits. Among them, fermented dairy foods have been associated with obesity prevention and in other conditions such as chronic diarrhea, hypersensitivity, irritable bowel syndrome, Helicobacter pylori infection, lactose intolerance, and gastroenteritis which all are intimately linked with an unhealthy way of life. A malfunctioning inflammatory response may affect the intestinal epithelial barrier’s ability to function by interfering with the normal metabolic processes. In this regard, several studies have shown that fermented dairy probiotics products improve human health by stimulating the growth of good bacteria in the gut at the same time increasing the production of metabolic byproducts. The fermented functional food matrix around probiotic bacteria plays an important role in the survival of these strains by buffering and protecting them from intestinal conditions such as low pH, bile acids, and other harsh conditions. On average, cultured dairy products included higher concentrations of lactic acid bacteria, with some products having as much as 109/mL or g. The focus of this review is on fermented dairy foods and associated probiotic products and their mechanisms of action, including their impact on microbiota and regulation of the immune system. First, we discussed whey and whey-based fermented products, as well as the organisms associated with them. Followed by the role of probiotics, fermented-product-mediated modulation of dendritic cells, natural killer cells, neutrophils, cytokines, immunoglobulins, and reinforcement of gut barrier functions through tight junction. In turn, providing the ample evidence that supports their benefits for gastrointestinal health and related disorders.

Postnatal probiotic supplementation can prevent and optimize treatment of childhood asthma and atopic disorders: A systematic review of randomized controlled trials

Background

Although several randomized controlled trials (RCTs) published over the past 5 years show that prenatal or postnatal probiotics may prevent or optimize the treatment of childhood asthma and atopic disorders, findings from the systematic reviews and meta-analyses of these studies appear inconsistent. More recent RCTs have focused on postnatal probiotics, and linked specific probiotic strains to better disease outcomes.

Objective

This systematic review aimed to determine if postnatal probiotics are as effective as prenatal probiotics in preventing or treating childhood asthma and atopic disorders.

Methods

We searched the PubMed, Medline, Google Scholar, and EMBASE databases for RCTs published within the past 5 years (from 2017 to 2022). We included only full-text RCTs on human subjects published in or translated into the English language. We retrieved relevant data items with a preconceived data-extraction form and assessed the methodological quality of the selected RCTs using the Cochrane Collaboration's tool for assessing the risk of bias in randomized trials. We qualitatively synthesized the retrieved data to determine any significant differences in study endpoints of the probiotic and placebo groups.

Results

A total of 1,320 participants (688 and 632 in the probiotic and placebo groups) from six RCTs were investigated. One RCT showed that early Lactobacillus rhamnosus GG (LGG) led to a reduction in the cumulative incidence rate of asthma. Another study demonstrated that mixed strains of Lactobacillus paracasei and Lactobacillus fermentum could support clinical improvement in children with asthma while one trial reported a significant reduction in the frequency of asthma exacerbations using a mixture of Ligilactobacillus salivarius and Bifidobacterium breve. Three trials showed that a combination of LGG and Bifidobacterium animalis subsp lactis, Lactobacillus rhamnosus alone, and a probiotic mixture of Lactobacillus ŁOCK strains improved clinical outcomes in children with atopic dermatitis and cow-milk protein allergy.

Conclusions

Postnatal strain-specific probiotics (in single or mixed forms) are beneficial in preventing and treating atopic dermatitis and other allergies. Similarly, specific strains are more effective in preventing asthma or improving asthma outcomes. We recommend more interventional studies to establish the most useful probiotic strain in these allergic diseases.

Gut Microbiome and Its Influence On Ocular Surface and Ocular Surface Diseases

ABSTRACT

The gut microbiome plays a substantial immunologic and pathophysiologic role in maintaining the health of the host, and dysregulation of this dynamic ecosystem has been associated with several inflammatory conditions. Many studies have explored the influence of gut microbiota on the ocular surface and whether gut microbiota impact the pathophysiology of ophthalmic conditions. These findings have highlighted the advantages of enhancing gut microbes through probiotics, prebiotics, diet, vitamin supplementations, and fecal microbial transplant in clinical practice. The purpose of this review article was to provide an up-to-date overview of the knowledge on this topic. Further exploration of this area of research is important to help guide new therapeutic targets to develop treatment and prevention of certain ocular surface diseases.

Comparing available treatments for pollen-induced allergic rhinitis in children

INTRODUCTION

Pollen-induced allergic rhinitis (PIAR) is a widespread disease in children, and its prevalence is rapidly evolving. In addition, it may be associated with other atopic diseases, in particular asthma. In most cases, PIAR can be treated effectively by avoiding exposure to responsible allergens and using symptomatic treatments, including intranasal/oral antihistamines or/and nasal corticosteroids, according to ARIA guidelines. In recent decades, new medicines have been studied and developed: allergen-specific immunotherapy (AIT), anti-IgE antibodies, and probiotics. In addition, nutraceuticals have also been used as add-on treatments. This review aims to discuss and compare the old and new therapeutic strategies for PIAR in children.

AREAS COVERED

Allergic rhinitis is a type 2 inflammatory disease. The management of patients with PIAR entails medications, AIT, and ancillary therapies. In addition, children with PIAR and associated severe asthma may be inclusively treated with biologics. Namely, subjects with allergic comorbidities could benefit from biological agents. However, AIT presently remains the unique causal treatment for PIAR.

EXPERT OPINION

New strategies may include combined treatments, mainly concerning fixed associations with antihistamines and corticosteroids, nutraceutical products, and new AIT formulations.

The effect of a probiotic on gastrointestinal symptoms due to menstruation in healthy adult women on oral contraceptives: randomized, double-blind, placebo-controlled trial protocol

Introduction

For many women, uncomfortable and stressful symptoms accompany the menstrual cycle each month, sometimes in a debilitating manner. Previous studies have reported that gastrointestinal symptoms in healthy women significantly differ by the day of the menstrual cycle, but few studies have assessed interventions intended to minimize these symptoms. Probiotics supplements have been shown to attenuate gastrointestinal symptom severity as well as self-reported feelings of stress in various populations. This study evaluates the effect of a probiotic on abdominal pain and gastrointestinal symptoms in healthy women who take an oral contraceptive, have regular menses, and typically experience these symptoms during menstruation with the primary aim being change in abdominal pain intensity related to the menstrual cycle with probiotic versus placebo supplementation.

Methods and analysis

In this randomized, double-blind, placebo-controlled parallel study, participants will receive either a probiotic or placebo supplement. Participants will begin answering questionnaires approximately 7 days before the start of menstruation (i.e., active bleeding), and 3 days later, they will begin consuming the study supplement for 8 weeks. The questionnaires administered will collect data about abdominal pain severity (primary outcome) and duration related to the menstrual cycle, digestive health, dietary intake, stress, and digestion-associated quality-of-life. A subgroup of women will provide weekly vaginal swabs and stool samples to examine the effect of the probiotic supplement on microbiota composition and diversity for exploratory purposes. Two-sided tests using a linear model and a type I error rate of α = 0.05 will be employed to test all hypotheses. Continuous variables will be presented as means with standard errors and categorical variables, as counts or proportions.

Ethics and dissemination

This study was reviewed and approved by the University of Florida Institutional Review Board 01. Written informed consent will be obtained from all participants prior to any study activities. Study findings will be disseminated at scientific conferences and publication in the trial registry or in a peer-reviewed journal. Any protocol amendments will be reported in the final manuscript of this study.

Trial registration

ClinicalTrials.gov NCT04457401. Registered prospectively on 07 July 2020. The trial was completed in December of 2021.

Protocol version

V4.0 (11-04-2020)

Trial status

Currently recruiting. Recruitment began in November 2020 and extend until December 2021.

The Efficacy and Safety of Probiotics for Allergic Rhinitis: A Systematic Review and Meta-Analysis

Background

Probiotics have proven beneficial in a number of immune-mediated and allergic diseases. Several human studies have evaluated the efficacy and safety of probiotics in allergic rhinitis; however, evidence for their use has yet to be firmly established.

Objective

We undertook a systematic review and meta-analysis aiming to address the effect and safety of probiotics on allergic rhinitis.

Methods

We systematically searched databases [MEDLINE (PubMed), Embase, and the Cochrane Central Register of Controlled Trials] from inception until June 1, 2021. Qualified literature was selected according to inclusion and exclusion criteria, the data were extracted, and a systematic review and meta-analysis was conducted.

Results

Twenty-eight studies were included. The results showed that probiotics significantly relieved allergic rhinitis symptoms (standardized mean difference [SMD], -0.29, 95% confidence interval (CI) [-0.44, -0.13]; p = 0.0003, I ² = 89%), decreased Rhinoconjunctivitis Quality of Life Questionnaire (RQLQ) scores compared with the control group (SMD, -0.64, 95% CI [-0.79, -0.49], p < 0.00001, I ² = 97%), and increased T helper cell 1(Th1)/Th2 ratio (mean difference [MD], -2.47, 95% CI [-3.27, -1.68], p < 0.00001, I ² = 72%). There was no significant change in overall or specific IgE levels between probiotic-treated and placebo-treated subjects (SMD, 0.09, 95% CI [-0.16, 0.34], I ² = 0%, and SMD, -0.03, 95% CI [-0.18, 0.13], p = 0.72, I ² = 0%, respectively).

Conclusions

To sum up, probiotic supplement seems to be effective in ameliorating allergic rhinitis symptoms and improving the quality of life, but there is high heterogeneity in some results after subgroup analysis and clinicians should be cautious when recommending probiotics in treating allergic rhinitis.

Systematic Review Registration

https://www.crd.york.ac.uk/PROSPERO/, PROSPERO (CRD42021242645).

The Beneficial Role of Probiotic Lactobacillus in Respiratory Diseases

Respiratory diseases cause a high incidence and mortality worldwide. As a natural immunobiotic, Lactobacillus has excellent immunomodulatory ability. Administration of some Lactobacillus species can alleviate the symptoms of respiratory diseases such as respiratory tract infections, asthma, lung cancer and cystic fibrosis in animal studies and clinical trials. The beneficial effect of Lactobacillus on the respiratory tract is strain dependent. Moreover, the efficacy of Lactobacillus may be affected by many factors, such as bacteria dose, timing and host background. Here, we summarized the beneficial effect of administered Lactobacillus on common respiratory diseases with a focus on the mechanism and safety of Lactobacillus in regulating respiratory immunity.

Effects of a Probiotic Formulation on Seasonal Allergic Rhinitis in Adults—A Randomized Double-Blind Placebo-Controlled Trial: The Probiotics for Hay Fever Trial

Background

Seasonal-allergic-rhinitis (hay fever) affects approximately 4.6 million (20%) Australians each year. Hay fever manifests as runny/blocked nose and often itchy/sore/swollen eyes, with symptoms greatly impacting the quality of life. Rescue medications such as antihistamines are often needed to restore function, but they may trigger some other unwanted side effects. Probiotics have shown promise to reduce hay fever symptoms.

Objective

In this randomized double-blind placebo-controlled 12-week trial, we aimed to assess the tolerability and efficacy of the probiotic formula “NC-Seasonal-Biotic” on symptoms, quality-of-life, and immunological and microbial factors.

Methods

Adults, who had previously suffered from hay fever symptoms, were screened for eligibility and randomly allocated to probiotic or placebo trial powder. Treatment effectiveness was assessed by questionnaires, daily total-nasal-symptom-score, and weekly rhinoconjunctivitis quality-of-life questionnaire. Secondary outcome measures included immunological parameters such as T-cell immunity (Th1/Th2 ratio) and the stool-microbiome analysis. Tolerability was assessed weekly by the gastrointestinal symptom scale.

Results

Recruitment and follow-up were challenging around the 2020/2021 hay fever season in Melbourne, Australia, due to the harsh COVID-19 restrictions and extended lockdowns. Out of the 82 adults enrolled in this study, 75% participated (n = 60), and half (n = 40) completed the 10–12-week intervention period. In the intention-to-treat analysis, no significant differences in hay fever symptoms were apparent between the groups, while quality-of-life trended toward greater improvement in the active group. Intention-to-treat analysis was confounded due to a third of all participants not completing the full 10–12-week-intervention period. Subgroup analyses of the participants (n = 40) completing the full 10–12-week study period revealed a significantly greater reduction in symptoms in the active group compared with the placebo group, including runny nose (p = 0.04) and itchy eyes (p = 0.01). Furthermore, the active group reported significant improvements in the quality-of-life, including more functionality during the day (p = 0.05), better sleep (p = 0.005), less fatigue (p = 0.04), less thirst (p = 0.007), and less irritability (p = 0.007). Immunological parameters, measured by T-helper cell ratio (Th1/Th2), improved significantly in the active group compared with the placebo group. Most microbial changes were not statistically different between the groups. The trial powder was generally well tolerated.

Conclusion

Our study suggests the probiotic formula “NC-Seasonal-Biotic,” taken for 10–12 weeks, as effective in reducing hay fever symptoms, such as runny nose and itchy eyes, and improved the quality-of-life and immunological parameters while being well tolerated.

Clinical Trial Registration

[www.ClinicalTrials.gov], identifier [ACTRN126200 01078943].

Validation of a novel quality of life questionnaire: the Digestion-associated Quality of Life Questionnaire (DQLQ)

Background

Few health-related quality of life (QOL) questionnaires are designed specifically for healthy populations and are specific to gastrointestinal (GI) symptoms even though healthy individuals may frequently experience gas, bloating, constipation, diarrhea, and abdominal pain. The purpose of this study was to develop and validate a tool that could assess the impact of GI symptoms on digestion-associated QOL in otherwise healthy individuals.

Methods

After a review of current literature and with input from experienced GI researchers, a 24-item questionnaire was created. The questionnaire was reduced to 9 items with input from focus groups comprised of healthy adults experiencing GI-related symptoms and through variability analysis. The Digestion-associated QOL Questionnaire (DQLQ) was designed to be sensitive to the physical and mental well-being changes that may occur due to GI symptoms. The DQLQ was assessed for internal consistency reliability (Cronbach’s alpha; McDonald’s omega), test–retest reliability (intraclass correlation coefficient, ICC), and construct validity (Pearson correlations) in a study with healthy, academically stressed, undergraduate students. Convergent validity was evaluated by correlating the DQLQ with gastrointestinal symptom rating scale (GSRS) scores. Divergent validity was assessed by correlating DQLQ scores with stress scores, and bowel satisfaction scores.

Results

A total of 594 students (age 18–30 years) completed the DQLQ. Internal consistency reliability was favorable (n = 594; α = 0.84, ω = 0.84). A high level of agreement and correlation between DQLQ scores was found with the test–retest reliability analysis (n = 273; ICC = 0.89). The questionnaire was shown to have good convergent validity through correlation with the GSRS (n = 594; r = 0.54). Divergent validity was also shown to be appropriate by correlating DQLQ scores with stress (n = 592; r = 0.13, p < 0.005), and bowel satisfaction (n = 592; r = 0.18, p < 0.001) scores.

Conclusion

The DQLQ is a reliable and valid questionnaire for assessing digestion-associated QOL in healthy individuals.

Effect of Probiotics on Respiratory Tract Allergic Disease and Gut Microbiota

Allergy is a hypersensitivity reaction triggered by specific cell or antibody-mediated immune mechanisms. Allergies have increased in industrialized countries in recent decades. The rise in allergic respiratory diseases such as allergic rhinitis (AR) and allergic asthma (AA) is a potential threat to public health. Searches were conducted using PubMed, Google Scholar and Medline using the following key terms: allergic rhinitis OR asthma AND probiotics, allergic airway inflammation AND immune disorders, probiotics OR gut microbiota AND allergic disease, probiotics AND inflammatory. Studies from all years were included, specifically those published within the last 10 years. Some review articles and their reference lists were searched to identify related articles. The role of microbiota in respiratory allergic diseases has attracted more and more attention. Pieces of evidence suggested that the development of allergic diseases causes a possible imbalance in the composition of the gut microbiota. Compared to colonized mice, germ-free mice exhibit exaggerated allergic airway responses, suggesting that microbial host interactions play an important role in the development of allergic diseases. Probiotics modulate both the innate and adaptive inflammatory immune responses, often used as dietary supplements to provide health benefits in gastrointestinal disorders. Probiotics may serve as immunomodulators and activators of host defense pathways. Besides, oral probiotics can modulate the immune response in the respiratory system. Recently, studies in humans and animals have demonstrated the role of probiotic in RA and AA. To understand the characterization, microbiota, and the potential role of probiotics intervention of AA/AR, this review provides an overview of clinical features of AA and AR, probiotics for the prevention and treatment of AR, AA, changes in gut microbiota, and their mechanisms of action.

Effect of Bifidobacterium bifidum on Clinical Characteristics and Gut Microbiota in Attention-Deficit/Hyperactivity Disorder

This study aimed to examine whether probiotics supplements using Bifidobacterium bifidum (Bf-688) can improve clinical characteristics and gut microbiomes among patients with attention-deficit/hyperactivity disorder (ADHD). This open-label, single-arm trial consisted of 30 children aged 4–16 years who met the criteria for ADHD diagnosis. Each subject took Bf-688, with one sachet in the morning and one in the evening (daily bacteria count 5 × 10⁹ CFUs), for 8 weeks. Patients’ clinical symptoms were assessed using the Swanson, Nolan, and Pelham Rating Scale (SNAP-IV). We collected stool samples at the baseline, the 8th week, and the 12th week for gut microbiota examination. During the 8-week Bf-688 supplement period, patients’ inattention symptoms and hyperactivity/impulsive symptoms improved, and their weights and BMIs increased. For gut microbiota, the Firmicutes to Bacteroidetes ratio (F/B ratio) decreased significantly. LEfSe analysis revealed that Firmicutes significantly decreased while Proteobacteria significantly increased during the 8-week treatment period. After Bf-688 was discontinued for 4 weeks (12 weeks from baseline), Bacteroidota significantly decreased and Shigella significantly increased. The probiotic Bf-688 supplement was associated with an improvement of clinical symptoms and with weight gain among ADHD children. Furthermore, gut microbiota composition was significantly altered by the Bf-688 supplement. A future randomized control trial is warranted to verify these findings.

Selenium-enriched Bacillus subtilis reduces the effects of mercury-induced on inflammation and intestinal microbes in carp (Cyprinus carpio var. specularis)

Mercury (Hg) is a global pollutant that affects the health of humans and ecosystems. Selenium (Se) is an essential trace element for many organisms including humans. Bacillus subtilis is one of the main probiotics used in aquaculture, and has a certain adsorption effect on heavy metals. The interaction between Hg and Se was rigorously studied, especially due to the observation of the protective effect of Se on Hg toxicity. The objective of this study was to research the effects of Hg, Se, and B. subtilis on inflammation and intestinal microbes in common carp. The common carp was exposed to Hg (0.03 mg/L), and 10⁵ cfu/g Se-rich B. subtilis was added to the feed. After 30 days of feeding, samples were taken to evaluate the growth performance, serological response, inflammatory response, and intestinal microbial changes. In this study, when fish were exposed to Hg, the growth performance of the Se-rich B. subtilis plus 0.03 mg/L Hg fish group was lower than that of the control group and higher than 0.03 mg/L Hg; The levels of serum immunoglobulin M (IgM) and lysozyme (LZM) decreased, but after supplementation with Se-rich B. subtilis, the levels of LZM and IgM increased; Hg treatment significantly upregulated the mRNA expression of interleukin-1β (IL-1β), interleukin-8 (IL-8), tumor necrosis factor-α (TNF-α), and nuclear factor-kB (NF-κB P65), but downregulated the mRNA expression of interleukin-10 (IL-10), transforming growth factor-β (TGF-β) and NF-kappa-B inhibitor alpha (IkBα). However, compared with the Hg group, the Se-rich B. subtilis plus Hg group can significantly increase the mRNA expression levels of IL-1β, IL-8, TNF-α, and NF-κB P65, but reduce the regulation of IL-10, TGF-β, and IkBα expression. Through the analysis of the microbiological, we found that the Hg group was mainly composed of Aeromonas sobria and Aeromonas hydrophila. However, in the Se-rich B. subtilis treatment group, we found that Aeromonas sobria was significantly less than the Hg group. Se-rich B. subtilis improves Hg-induced intestinal microbial changes, alleviates the abundance of Aeromonas, and alleviates the inflammation of the fish. The results of this study show that Se-rich B. subtilis dietary supplements can effectively protect common carp against Hg toxicity.

Microbiota and Ocular Diseases

Recent advances have identified significant associations between the composition and function of the gut microbiota and various disorders in organ systems other than the digestive tract. Utilizing next-generation sequencing and multiomics approaches, the microbial community that possibly impacts ocular disease has been identified. This review provides an overview of the literature on approaches to microbiota analysis and the roles of commensal microbes in ophthalmic diseases, including autoimmune uveitis, age-related macular degeneration, glaucoma, and other ocular disorders. In addition, this review discusses the hypothesis of the "gut-eye axis" and evaluates the therapeutic potential of targeting commensal microbiota to alleviate ocular inflammation.

Bioflocs attenuates lipopolysaccharide-induced inflammation, immunosuppression and oxidative stress in Channa argus

The regulation of C/N in aquaculture water is an important means of environmental regulation, of which the most common is bioflocs technology (BFT). Here, an eight-week feeding experiment and a lipopolysaccharide (LPS) challenge test were proceed to investigate the growth, oxidative stress, immunosuppression and GR-NF-κB related genes expression of Channa argus rearing in the BFT. Four groups were set, the control group was a basic diet (C/N = 7.6:1), and the other three groups were adjusted by glucose, which was C/N 10: 1, C/N 15: 1 and C/N 20:1, respectively. And we detected the two-stage test indexes of C. argus before and after the LPS challenge. The results showed that the bioflocs of C/N 15:1 group significantly (P < 0.05) promoted the growth performance. Similarly, the trend of immune enzyme activity was the same before and after LPS challenge, but decreased after challenge (except AKP and IgM). The best group is still treatment C/N 15:1. Liver and intestine SOD, CAT, GPX, ASA and T-AOC levels of juveniles in treatment C/N 15:1 were markedly increased (P < 0.05) compared to control before and after the LPS challenge. Simultaneously, the content of MDA in control group was considerably higher than that in treatment C/N 15:1 (P < 0.05). Furthermore, C/N 15:1 group significantly down-regulated the expression level of pro-inflammatory factors (NF-κB, TNF-α, IL-1β and IL-8), and up-regulated IκBα, GR, HSP70 and HSP90 expression levels considerably (P < 0.05). Also, intestinal morphology appeared injury in control group, while intestinal integrity was better in treatment C/N 10:1 and C/N 15:1 after challenge. Taken together, these upshot indicated that bioflocs could enhance growth and alleviate C. argus from LPS-induced oxidative stress, immunosuppression and inflammation through restraining GR-NF-κB signaling pathway. The best C/N ratio for alleviating LPS is 15:1.

The Role of Upper Airway Microbiome in the Development of Adult Asthma

Clinical and molecular phenotypes of asthma are complex. The main phenotypes of adult asthma are characterized by eosinophil and/or neutrophil cell dominant airway inflammation that represent distinct clinical features. Upper and lower airways constitute a unique system and their interaction shows functional complementarity. Although human upper airway contains various indigenous commensals and opportunistic pathogenic microbiome, imbalance of this interactions lead to pathogen overgrowth and increased inflammation and airway remodeling. Competition for epithelial cell attachment, different susceptibilities to host defense molecules and antimicrobial peptides, and the production of proinflammatory cytokine and pattern recognition receptors possibly determine the pattern of this inflammation. Exposure to environmental factors, including infection, air pollution, smoking is commonly associated with asthma comorbidity, severity, exacerbation and resistance to anti-microbial and steroid treatment, and these effects may also be modulated by host and microbial genetics. Administration of probiotic, antibiotic and corticosteroid treatment for asthma may modify the composition of resident microbiota and clinical features. This review summarizes the effect of some environmental factors on the upper respiratory microbiome, the interaction between host-microbiome, and potential impact of asthma treatment on the composition of the upper airway microbiome.

Probiotics as a Possible Strategy for the Prevention and Treatment of Allergies. A Narrative Review

Allergies are an increasing global public health concern, especially for children and people living in urban environments. Allergies impair the quality of life of those who suffer from them, and for this reason, alternatives for the treatment of allergic diseases or reduction in their symptoms are being sought. The main objective of this study was to compile the studies carried out on probiotics as a possible therapy for allergies. The most studied allergies on which probiotics have been shown to have a beneficial effect are rhinitis, asthma, and atopic dermatitis. Most studies have studied the administration of Lactobacillus and Bifidobacterium spp. in children and have shown beneficial effects, such as a reduction in hyperreactivity and inflammation caused by allergens and a decrease in cytokine release, among other beneficial effects. In the case of children, no clear beneficial effects were found in several studies, and the potential risk from the use of some opportunistic bacteria, such as probiotics, seems controversial. In the studies that reported beneficial results, these effects were found to make allergy symptoms less aggressive, thus reducing morbidity in allergy sufferers. The different effects of the same probiotic bacteria on different patients seem to reinforce the idea that the efficacy of probiotics is dependent on the microbial species or strain, its derived metabolites and byproducts, and the gut microbiota eubiosis of the patient. This study is relevant in the context of allergic diseases, as it provides a broader understanding of new alternatives for the treatment of allergies, both in children, who are the main sufferers, and adults, showing that probiotics, in some cases, reduce the symptoms and severity of such diseases.

Strain-Specific Effects of Bifidobacterium longum on Hypercholesterolemic Rats and Potential Mechanisms

Hypercholesterolemia is an independent risk factor of cardiovascular disease, which is among the major causes of death worldwide. The aim of this study was to explore whether Bifidobacterium longum strains exerted intra-species differences in cholesterol-lowering effects in hypercholesterolemic rats and to investigate the potential mechanisms. SD rats underwent gavage with each B. longum strain (CCFM 1077, I3, J3 and B3) daily for 28 days. B. longum CCFM 1077 exerted the most potent cholesterol-lowering effect, followed by B. longum I3 and B3, whereas B. longum B3 had no effect in alleviating hypercholesterolemia. Divergent alleviation of different B. longum strains on hypercholesterolemia can be attributed to the differences in bile salt deconjugation ability and cholesterol assimilation ability in vitro. By 16S rRNA metagenomics analysis, the relative abundance of beneficial genus increased in the B. longum CCFM 1077 treatment group. The expression of key genes involved in cholesterol metabolism were also altered after the B. longum CCFM 1077 treatment. In conclusion, B. longum exhibits strain-specific effects in the alleviation of hypercholesterolemia, mainly due to differences in bacterial characteristics, bile salt deconjugation ability, cholesterol assimilation ability, expressions of key genes involved in cholesterol metabolism and alterations of gut microbiota.

Monitoring oxidative stress, immune response, Nrf2/NF-κB signaling molecules of Rhynchocypris lagowski living in BFT system and exposed to waterborne ammonia

The present study was implemented to evaluate oxidative stress, immune response, Nrf2 and NF-κB signaling molecules related genes expression of Rhynchocypris lagowski living in biofloc technology (BFT) system and exposed to waterborne ammonia. According to the differences of C:N ratios, the experiment was divided into four groups: C:N 10.8:1 (control group), C:N 15:1, C:N 20: 1 and C:N 25:1. The results demonstrated that BFT can effectively regulate water quality and promote growth, and the C:N 20:1 group has the most significant effect (P < 0.05). Besides, significant increases in immune enzymes (lysozyme, complement C3, C4, immunoglobulin M and nitric oxide synthase) and anti-inflammatory factor (IL-2) activity of R. lagowski were emerged in the treatment C:N 20:1 after the 56-d growth experiment and the challenging trial (P < 0.05). Comparing the antioxidant status of R. lagowski in liver and gut before and after ammonia stress: superoxide dismutase, total antioxidant capacity and catalase activity in treatments C:N 20:1 were significant increased (P < 0.05), while the level of malondialdehyde was marked lower than that in control. Meanwhile, treatment C:N 20:1 considerably upregulated Nrf2 signaling molecules related genes and significantly down-regulated the expression of pro-inflammatory factor gene in NF-κB signaling pathway compared with the control (P < 0.05). These results indicated that BFT could enhance growth, antioxidant and immune response and regulate Nrf2 and NF-κB related genes expression in R. lagowski, with most excellent effects in fish given C:N 20:1 group.

Alleviative effects of dietary microbial floc on copper-induced inflammation, oxidative stress, intestinal apoptosis and barrier dysfunction in Rhynchocypris lagowski Dybowski

The heavy metal poisoning in humans and fish represents a significant global problem. Copper (Cu), as an essential micronutrient in human and animal metabolism, often accumulates excessively in aquatic environment. The microbial floc is rich in a variety of probiotics and bioactive compounds, which has been documented to have the functions of antioxidant and immunoenhancement. A 64-day experiment was conducted to investigate the protective effects and potential mechanisms of dietary supplementation of microbial floc and Cu exposure on inflammatory response, oxidative stress, intestinal apoptosis and barrier dysfunction in Rhynchocypris lagowski Dybowski. A total of four hundred fifty R. lagowski were fed five experimental diets containing graded levels of microbial floc from 0% to 16% (referred to as B0, B4, B8, B12 and B16, respectively) in the first 60 days, and 96 h of acute copper exposure test was carried out in the last four days. The results showed that microbial floc exerted significant alleviative effects by preventing alterations in the levels of bioaccumulation, caspase3, caspase8, caspase9, malondialdehyde and interleukin-6, improving the activities of lysozyme, complement C3, complement C4, immunoglobulin M, alkaline phosphatase, heat shock protein 70, heat shock protein 90 and glutathione peroxidase, catalase, superoxide dismutase, total antioxidant capacity. In addition, microbial floc assisted in regulating the expression of NF-κB/Nrf2 signaling molecule genes, including NF-κB, TNF-α, IL-1β, IL-8, IL-10, TGF-β, Keap1, Nrf2, Maf, HO-1, CAT, CuZn-SOD, GCLC and GPX. Overall, our results suggest that dietary supplementation with of microbial floc can alleviate copper-induced inflammation, oxidative stress, intestinal apoptosis and barrier dysfunction in R. lagowski. A suitable supplementation level of approximately 12% microbial floc is recommended in the present study.

Probiotics function and modulation of the immune system in allergic diseases

Allergic diseases have been a global problem over the past few decades. The effect of allergic diseases on healthcare systems and society is generally remarkable and is considered as one of the most common causes of chronic and hospitalized disease. The functional ability of probiotics to modulate the innate/acquired immune system leads to the initiation of mucosal/systemic immune responses. Gut microbiota plays a beneficial role in food digestion, development of the immune system, control/growth of the intestinal epithelial cells and their differentiation. Prescribing probiotics causes a significant change in the intestinal microflora and modulates cytokine secretion, including networks of genes, TLRs, signaling molecules and increased intestinal IgA responses. The modulation of the Th1/Th2 balance is done by probiotics, which suppress Th2 responses with shifts to Th1 and thereby prevent allergies. In general, probiotics are associated with a decrease in inflammation by increasing butyrate production and induction of tolerance with an increase in the ratio of cytokines such as IL-4, IL-10/IFN-γ, Treg/TGF-β, reducing serum eosinophil levels and the expression of metalloproteinase-9 which contribute to the improvement of the allergic disease's symptoms. Finally, it can be said that the therapeutic approach to immunotherapy and the reduction of the risk of side effects in the treatment of allergic diseases is the first priority of treatment and the final approach that completes the first priority in maintaining the condition and sustainability of the tolerance along with the recovery of the individual.

Effect of acute exposure to ammonia and BFT alterations on Rhynchocypris lagowski: Digestive enzyme, inflammation response, oxidative stress and immunological parameters

Biofloc technology (BFT) is a new green culture technology that is intended not merely to eradicate nitrogenous residues but also enhance immunity and antioxidant activity in aquatic animals. A 56-day feeding trial and a 96 h ammonia challenge test were implemented to evaluate the effect of acute exposure to ammonia and BFT alterations on Rhynchocypris lagowski: digestive enzyme, inflammation response, oxidative stress and immunological parameters in zero water exchange tanks. According to the differences of C/N ratios, the experiment was divided into four groups: C/N 10.8:1 (control group), C/N 15:1, C/N 20: 1 and C/N 25:1. The results provided evidence that weight gain rate (WGR), specific growth rate (SGR) and protein efficiency ratio (PER) were significantly elevated in C/N 20, while food conversion rate (FCR) was considerably decreased (P < 0.05) compared to the control. Significant increases in digestive enzyme amylase (AMS), lipase (LPS), protease (PRS) and cellulase (CES) activity; Immune enzyme complement C3, complement C4, Nitric Oxide Synthase (NOS) and immunoglobulin M (IgM) activity; Serum biochemical lysozyme (LSZ), glutamic pyruvic transaminase (GPT), glutamic oxaloacetic transaminase (GOT) and alkaline phosphatase (AKP) activity; Inflammation TNF-α, IL-1β, IL-2, IL-6 of R. lagowskis were found in the C/N 20 group after a 56-day feeding trial and a challenging trial (P < 0.05). Comparing the antioxidant capacity of R. lagowski in gills, brains and spleen of juveniles from the four experimental groups, the activity of superoxide dismutase (SOD), total antioxidant capacity (T-AOC), catalase (CAT) activity and glutathion reductases (GR) activity of juveniles in the C/N 20 group were significant higher (P < 0.05), and the content of malondialdehyde (MDA) was considerably lower than that in the control. Overall, these findings suggest that BFT not only can enhance R. lagowski growth performance, digestive enzyme activity, and strengthen antioxidant status but also upgrade immune response, improve the ability of resistance to ammonia stress.

Ocular allergy: update on clinical trials

PURPOSE OF REVIEW

The purpose of this article is to provide an update on the advances made through recent clinical trials regarding the treatment of the signs and symptoms of allergic conjunctivitis and its associated conditions.

RECENT FINDINGS

Recent studies have demonstrated significant advancement in the various forms of immunotherapy treatments. Nutritional interventions such as probiotics have surfaced as a viable complementary treatment option. Novel delivery methods such as contact lenses have been further studied along with a new tacrolimus formulation to improve ocular levels of the drug.

SUMMARY

Currently, the primary advances in treatment for allergic conjunctivitis has shifted from new ophthalmic agents to immunotherapy and improvement of drug delivery. This includes the classic subcutaneous and sublingual and the novel epicutaneous and intralymphatic immunotherapy delivery systems as well as an edible rice vaccine. New targets for treatment have spurred research into new antagonist drugs such as (OC000459), a prostaglandin D2 antagonist. The Marinosolv formulation using tacrolimus shows promise and may be considered for other ophthalmic agents in the future. Other nonpharmacological treatments such as stenting and mechanical barrier gel have demonstrated their usefulness in treating ocular symptoms.

Probiotics as a functional food ingredient in allergic diseases: regulation of CD4+ T helper cell differentiation

Allergic diseases are increasing worldwide, associating with increased health costs and decreased quality of life. Allergy is immune-related diseases caused by an allergic immune response to innocuous substance in the environment. At present, research has focussed on the study of the relevance to the microbiome and the phenotypes of allergy, including the relationships among the gastrointestinal microbiome, immune function, and allergic sensitisation. Probiotics as functional food ingredient are thought to secrete functional metabolites that have antibacterial effects on ameliorating intestinal health and CD4+ T helper cells-mediated immunity. This review will summarise the role of probiotics in the immune regulation and flora balance, highlighting recent advances in our understanding of the imbalance of Th subsets and cytokine leading to the immunopathology of allergic reactions. Finally, we discussed the unresolved problems and future research directions in order to promote the clinical application of probiotics immunotherapy.

A critical review of antibiotic resistance in probiotic bacteria

Probiotics are defined as live microorganisms that, when administered in adequate amounts, confer a health benefit upon the host. At present, probiotics are gaining popularity worldwide and are widely used in food and medicine. Consumption of probiotics is increasing with further in-depth research on the relationship between intestinal flora and host health. Most people pay more attention to the function of probiotics but ignore their potential risks, such as infection and antibiotic resistance transfer to pathogenic microbes. Physiological functions, effects and mechanisms of action of probiotics were covered in this review, as well as the antibiotic resistance phenotypes, mechanisms and genes found in probiotics. Typical cases of antibiotic resistance of probiotics were also highlighted, as well as the potential risks (including pathogenicity, infectivity and excessive immune response) and corresponding strategies (dosage, formulation, and administration route). This timely study provides an avenue for further research, development and application of probiotics.

Stool frequency and form and gastrointestinal symptoms differ by day of the menstrual cycle in healthy adult women taking oral contraceptives: a prospective observational study

Background

Little is known about how the menstrual cycle affects gastrointestinal function and self-reported stress in young, healthy women taking oral contraceptives (OC). This study prospectively characterized gastrointestinal function and symptoms on each day throughout the menstrual cycle.

Methods

Healthy women aged 18–35 years (n = 78) who took OC participated in the 5-week observational study. Stool frequency, self-reported stress, stool form measured by the Bristol Stool Form Scale (BSFS), and gastrointestinal symptoms measured by a modified version of the Gastrointestinal Symptom Rating Scale (GSRS) were assessed daily. GSRS scores were reported (1 = no discomfort at all, 7 = very severe discomfort) and were averaged for individual syndrome scores or summed for the total score. The validated, weekly version of the GSRS was completed at two time points to reflect menstruation and 1 week prior to menstruation (n = 72). Outcomes were analyzed in linear mixed models with the Dunnett’s post hoc test against day 1 of menstrual bleeding or with nonparametric tests.

Results

Daily stress (P = 0.0018), BSFS score (P = 0.0493), stool frequency (P = 0.0241), abdominal pain (P < 0.0001), diarrhea (P = 0.0022), constipation (P = 0.0446), reflux (P = 0.0193), and indigestion (P < 0.0001) all varied significantly by the day of the menstrual cycle. Dunnett’s post hoc tests showed that scores (mean ± SEM) on the first day of bleeding (day 1) for daily abdominal pain (2.6 ± 0.2), diarrhea (1.7 ± 0.1), and indigestion (2.1 ± 0.2) symptoms were higher than scores on all other days of the menstrual cycle (P < 0.05) with scores not on day 1 falling under 1.5, or between no discomfort at all and slight discomfort. Reflux, stool frequency, BSFS, self-reported stress, and constipation were higher on day 1 (P < 0.05) than on 12, 8, 6, 4, and 2 other days of the menstrual cycle, respectively. The median (IQR) GSRS score was higher during the week of menstruation than the week prior to menstruation for diarrhea [1.50 (1.00–2.33) vs 1.33 (1.00–2.00), P = 0.002] and abdominal pain [2.00 (1.33–2.67) vs 1.67 (1.33–2.33), P = 0.011] syndrome scores.

Conclusion

Bowel habits appear to vary across the menstrual cycle and suggest more gastrointestinal discomfort on day 1 of menstrual bleeding in healthy women taking OC. Future interventional studies could identify ways to improve gastrointestinal symptoms in healthy women during menstruation.

Bioflocs protects copper-induced inflammatory response and oxidative stress in Rhynchocypris lagowski Dybowski through inhibiting NF-κB and Nrf2 signaling pathways

Copper (Cu) is an essential element in the metabolic process of humans and animals, but it can cause toxicity at high concentrations of exposure. Bioflocs has been proved to have antioxidant, immune-enhancing and anti-inflammatory properties. Here, the purpose of this study was to evaluate potential mechanisms and protective effects of bioflocs and Cu exposure on inflammatory response, oxidative stress and immune-related genes and protein expression in Rhynchocypris lagowski Dybowski. 360 healthy R. lagowski were irregularly distributed among 12 tanks (3 tanks per group, 30 fish per tank). The experiment was divided into two parts: the feeding experiment was carried out in the first eight weeks, followed by acute copper exposure for 96 h. Then we selected the stressed fish for experimental analysis. The results provided evidences that bioflocs protected the R. lagowski by inhibiting the accumulation of copper, the activity of immune enzymes and the expression of NF-κB signaling pathway related genes and proteins, and the activity of antioxidant enzymes and the expression of Nrf2 signaling pathway related genes. Overall, these findings suggest that bioflocs could regulate the activation of Nrf2 and protect acute copper exposure induced inflammatory response by inhibiting the NF-κB signaling pathway in R. lagowski.

Effects of a multispecies synbiotic on glucose metabolism, lipid marker, gut microbiome composition, gut permeability, and quality of life in diabesity: a randomized, double-blind, placebo-controlled pilot study

Purpose

Diabesity, the combination of obesity and type 2 diabetes, is an ever-growing global health burden. Diabesity-associated dysbiosis of the intestinal microbiome has gained attention as a potential driver of disease and, therefore, a possible therapeutic target by means of pro- or prebiotic supplementation. This study tested the effects of a multispecies synbiotic (i.e. a combination of probiotics and prebiotics) on glucose metabolism, gut microbiota, gut permeability, neutrophil function and quality of life in treatment-experienced diabesity patients.

Methods

A randomized, double-blind, placebo-controlled pilot study with 26 diabesity patients was conducted in which patients received a daily dose of a multispecies probiotic and a prebiotic (or a placebo) for 6 months.

Results

There were no changes in glucose metabolism or mixed meal tolerance test responses throughout the study. The analysis of secondary outcomes revealed beneficial effects on hip circumference [− 1 (95% CI − 4; 3) vs +3 (− 1; 8) cm, synbiotics vs. placebo, respectively, p = 0.04], serum zonulin [− 0.04 (− 0.2; 0.1) vs +0.3 (− 0.05; 0.6) ng/ml, p = 0.004)] and the physical role item of the SF36 quality of life assessment [+ 5.4 (− 1.7; 12.5) vs − 5.0 (− 10.1; 0.2) points, p = 0.02] after 3 months of intervention, and lipoprotein (a) [− 2.1 (− 5.7; 1.6) vs +3.4 (− 0.9; 7.9) mg/dl, p = 0.02] after 6 months. There were no significant differences in alpha or beta diversity of the microbiome between groups or time points.

Conclusions

Glucose metabolism as the primary outcome was unchanged during the intervention with a multispecies synbiotic in patients with diabesity. Nevertheless, synbiotics improved some symptoms and biomarkers of type 2 diabetes and aspects of quality of life suggesting a potential role as adjuvant tool in the management of diabesity.

Graphic abstract

Electronic supplementary material

The online version of this article (10.1007/s00394-019-02135-w) contains supplementary material, which is available to authorized users.

Effects of a probiotic treatment (Enterococcus faecalis) and open-label placebo on symptoms of allergic rhinitis: study protocol for a randomised controlled trial

INTRODUCTION

Several studies suggest that gut microbiota may play an important role in allergic diseases. The present trial aims to examine effects of the probiotic Enterococcus faecalis on symptoms of allergic rhinitis in patients. Effects of this probiotic on the immune system have been reported by several studies, but the majority of the previous trials were animal studies. In addition, it is well known that symptoms in allergic rhinitis are prone to exhibit high placebo responses. Moreover, recent studies report that even placebos without deception (open-label placebos) are highly effective in reducing symptoms of allergic rhinitis. Our study design combines both new approaches to assess effects on allergic symptoms in patients. The objective of this study is to compare the effects of a probiotic treatment (E. faecalis) with effects seen by open-label placebo, concealed placebo treatment and no treatment control.

METHODS AND ANALYSIS

A total of 120 patients with allergic rhinitis will be randomly assigned to one of four different groups: a double-blind probiotic/placebo group (groups 1 and 2), an open-label placebo group (group 3) and a no-treatment group (group 4) to control for spontaneous variation of symptoms. The primary outcome is the evaluation of allergic symptoms using the Combined Symptoms Medication Score. Furthermore, health-related quality of life is examined (Rhinitis Quality of Life Questionnaire). Secondary outcomes include a visual analogue scale on allergic burden and a second quality of life questionnaire. This report describes the study design of the randomised controlled trial.

ETHICS AND DISSEMINATION

The study design was approved by the ethical committee of the UKT Department of Psychosomatic Medicine and Psychotherapy, Tübingen, Germany. The trial is registered at the German Clinical Trials Register (www.drks.de, DRKS00015804). The trial results will be published in peer-reviewed journals and at conferences.

TRIAL REGISTRATION NUMBER

German Clinical Trials Register (www.drks.de, DRKS00015804); Pre-results.

Probiotic survival during a multi-layered tablet development as tested in a dynamic, computer-controlled in vitro model of the stomach and small intestine (TIM-1)

The aim of the research was to develop a galenical formulation for the combination of the three probiotic strains Lactobacillus gasseri PA 16/8, Bifidobacterium longum SP 07/3 and Bifidobacterium bifidum MF 20/5 that would lead to the presence of a high amount of viable cells in the small intestine, the presumed site of action of these strains. This was tested in a validated, dynamic in vitro model of the stomach and small intestine (TIM‐1), simulating human adults after intake of a meal. Experiments were performed both in the gastric compartment of the model, as well as in the complete system (stomach + small intestine). Survival of the strains in an unformulated probiotic powder after transit through the gastric compartment was 5·3% for the bifidobacteria and 1% for L. gasseri. After transit through the complete gastrointestinal tract, this dropped to 2% for bifidobacteria and 0·1% for Lactobacillus. After several rounds of optimization, an enteric‐coated tablet was developed that increased the delivery of viable cells reaching the small intestine to 72% (gastric survival) for bifidobacteria, and 53% (gastric) for L. gasseri. Also survival in the small intestine increased by about an order of magnitude. The final galenical formulation was tested in two applications: adults and elderly, both of which have their own physiological parameters. These experiments corroborated the results obtained in the development phase of the project. In conclusion, the developed enteric coating led to a 20‐ to 40‐fold increase in the delivery of viable cells to the small intestine.

Significance and Impact of the Study

Predictive GI in vitro models are very helpful and reliable tools for the development of new galenical formula containing probiotics, and in the current example helped to deliver >10‐fold higher numbers of viable cells to the small intestine, presumably leading to improved functionality of the strains.

Study of Bioaccumulation, Hematological Parameters, and Antioxidant Responses of Carassius auratus gibelio Exposed to Dietary Lead and Bacillus subtilis

Lead (Pb) is one of the most ubiquitous and toxic elements in the aquatic environment. Bacillus subtilis (B. subtilis) is a widely used probiotic in aquaculture. The aim of this study was to explore the toxic effects on bioaccumulation, hematological parameters, and antioxidant responses of Carassius auratus gibelio (C. gibelio) exposed to dietary lead at 0, 120, and 240 mg/kg and/or B. subtilis at 10⁹ cfu/g. At 15 and 30 days, the fish were sampled and bioaccumulation, hematological parameters, and antioxidant responses were assessed. The result showed that B. subtilis administration can provide a significant protection against lead toxicity by reducing lead bioaccumulation in tissues, increasing the antioxidant enzymes activity, recovering δ-aminolevulinic acid dehydratase activity and optimizing the hematological parameters. Our results suggested that administration of B. subtilis (109 cfu/g) has the potential to combat dietary lead toxicity in C. gibelio.

Cutting Edge: Probiotics and Fecal Microbiota Transplantation in Immunomodulation

Probiotics are commensal or nonpathogenic microbes that confer beneficial effects on the host through several mechanisms such as competitive exclusion, antibacterial effects, and modulation of immune responses. Some probiotics have been found to regulate immune responses via immune regulatory mechanisms. T regulatory (Treg) cells, T helper cell balances, dendritic cells, macrophages, B cells, and natural killer (NK) cells can be considered as the most determinant dysregulated mediators in immunomodulatory status. Recently, fecal microbiota transplantation (FMT) has been defined as the transfer of distal gut microbial communities from a healthy individual to a patient's intestinal tract to cure some immune disorders (mainly inflammatory bowel diseases). The aim of this review was followed through the recent literature survey on immunomodulatory effects and mechanisms of probiotics and FMT and also efficacy and safety of probiotics and FMT in clinical trials and applications.

Effect of sub-chronic exposure to lead (Pb) and Bacillus subtilis on Carassius auratus gibelio: Bioaccumulation, antioxidant responses and immune responses

Lead (Pb) poisoning in humans and fish represents a significant global problem. Bacillus subtilis (B. subtilis) is a widely used probiotic in aquaculture. Carassius auratus gibelio (C. gibelio) is one of the most important aquaculture species with great commercial value. The objective of this study was to evaluate the potential of B. subtilis in ameliorating lead-induced toxicity in C. gibelio. The fish were exposed for 60 days to waterborne Pb at 0, 0.05, 0.5 and 1 mg/L and/or dietary B. subtilis at 10⁹ cfu/g. After 30 and 60 days, the fish were sampled and bioaccumulation, antioxidant activity and immune responses were assessed. The results revealed that B. subtilis confers significant protective effects against lead toxicity by preventing alterations in the levels of bioaccumulation, superoxide dismutase, catalase and glutathione. B. subtilis also assists in the recovery of blood δ-aminolevulinic acid dehydratase, lysozyme, and IgM levels while regulating the expression of immune-related genes including IL-10, lysozyme, TNF-α, IgM and Hsp70 after 60 days of lead exposure. Our results suggest that administration of B. subtilis (10⁹ cfu/g) has the potential to combat lead toxicity in C. gibelio.