Meta-analysis of probiotics for the treatment of irritable bowel syndrome

The Efficacy of Probiotics Supplementation on the Quality of Life of Patients with Gastrointestinal Disease: A Systematic Review of Clinical Studies

Patients with gastrointestinal (GI) disorders might benefit from probiotic supplementation to resolve their bowel symptoms and enhance their quality of life (QoL). This systematic review aimed to evaluate the effects of oral probiotic supplementation on improving QoL. Relevant studies were systematically searched in online databases, including PubMed, Scopus, Embase, ProQuest, and Google Scholar up to September 2022 using relevant keywords. Studies that were conducted on GI patients and presented QoL outcomes were included. The Revised Cochrane Risk of Bias 2 tool and the Risk Of Bias In Non-randomized Studies of Intervention tool were used to assess the risk of bias. Of the 4,555 results found in the systematic search of databases, only 36 studies were eligible for evaluation. According to this systematic review, 24 studies reported improvements, whereas 12 studies reported no improvements on QoL in GI patients supplemented with probiotics. We found that probiotics may improve the QoL of patients with GI diseases and related metabolic complications. Therefore, probiotics can be a useful supportive treatment strategy in these patients.

Safety evaluation of Bifidobacterium animalis subsp. lactis BLa80 under in vitro, and in vivo conditions

Bifidobacterium animalis subsp. lactis BLa80 is a new probiotic strain with extensive applications in food products both domestically and internationally. Given the rising consumption of this probiotic, its safety assessment is increasingly crucial in the food industry. This study evaluates the safety of strain BLa80 using a combination of in vitro and in vivo assays along with genomic analysis. Methods included exposing the strain to artificial gastric and intestinal fluids, as well as a medium containing bile salts, to stimulate human digestive conditions. The strain showed high tolerance to gastric fluid at pH of 2.5 and to 0.3 % bile salts. It maintained a 99.92 % survival rate in intestinal fluid. Additional tests assessed hemolytic activity, antibiotic susceptibility (revealing sensitivity to 7 antibiotics), and biogenic amine production using HPLC-ELSD, confirming the absence of histamine, and other harmful amines. Bile salt hydrolase activity was demonstrated qualitatively, and metabolic byproducts were quantitatively analyzed using a D-/l-lactic acid assay kit, showing that BLa80 produces 1.48 mg/mL of l-lactic acid and no harmful d-lactic acid. Genomic analysis confirmed the absence of virulence or pathogenicity genes, and a 90-day oral toxicity study in rats confirmed no toxic effects at various doses. Overall, these findings support the safety classification of the strain BLa80.

Computational prediction of new therapeutic effects of probiotics

Probiotics are living microorganisms that provide health benefits to their hosts, potentially aiding in the treatment or prevention of various diseases, including diarrhea, irritable bowel syndrome, ulcerative colitis, and Crohn's disease. Motivated by successful applications of link prediction in medical and biological networks, we applied link prediction to the probiotic-disease network to identify unreported relations. Using data from the Probio database and International Classification of Diseases-10th Revision (ICD-10) resources, we constructed a bipartite graph focused on the relationship between probiotics and diseases. We applied customized link prediction algorithms for this bipartite network, including common neighbors, Jaccard coefficient, and Adamic/Adar ranking formulas. We evaluated the results using Area under the Curve (AUC) and precision metrics. Our analysis revealed that common neighbors outperformed the other methods, with an AUC of 0.96 and precision of 0.6, indicating that basic formulas can predict at least six out of ten probable relations correctly. To support our findings, we conducted an exact search of the top 20 predictions and found six confirming papers on Google Scholar and Science Direct. Evidence suggests that Lactobacillus jensenii may provide prophylactic and therapeutic benefits for gastrointestinal diseases and that Lactobacillus acidophilus may have potential activity against urologic and female genital illnesses. Further investigation of other predictions through additional preclinical and clinical studies is recommended. Future research may focus on deploying more powerful link prediction algorithms to achieve better and more accurate results.

Association of intestinal dysbiosis with susceptibility to multiple sclerosis: Evidence from different population studies (Review)

Understanding the relationship between microorganisms that live in our intestines and neuroinflammatory and neurodegenerative pathologies of the central nervous system (CNS) is essential, since they have been shown to have an immunomodulatory effect in neurological disorders, such as multiple sclerosis (MS). The gut microbiota can be affected by several environmental factors, including infections, physical and emotional stress and diet, the latter known as the main modulator of intestinal bacteria. An abrupt shift in the gut microbiota composition and function is known as dysbiosis, a state of local and systemic inflammation produced by pathogenic bacteria and its metabolites responsible for numerous neurological symptoms. It may also trigger neuronal damage in patients diagnosed with MS. Intestinal dysbiosis affects the permeability of the intestine, allowing chronic low-grade bacterial translocation from the intestine to the circulation, which may overstimulate immune cells and cells resident in the CNS, break immune tolerance and, in addition, alter the permeability of the blood-brain barrier (BBB). This way, toxins, inflammatory molecules and oxidative stress molecules can pass freely into the CNS and cause extensive damage to the brain. However, commensal bacteria, such as the Lactobacillus genus and Bacteroides fragilis, and their metabolites (with anti-inflammatory potential), produce neurotransmitters such as γ-aminobutyric acid, histamine, dopamine, norepinephrine, acetylcholine and serotonin, which are important for neurological regulation. In addition, reprogramming the gut microbiota of patients with MS with a healthy gut microbiota may help improve the integrity of the gut and BBB, by providing clinically protective anti-inflammatory effects and reducing the disease's degenerative progression. The present review provides valuable information about the relationship between gut microbiota and neuroinflammatory processes of the CNS. Most importantly, it highlights the importance of intestinal bacteria as an environmental factor that may mediate the clinical course of MS, or even predispose to the outbreak of this disease.

Using metabolomics to understand stress responses in Lactic Acid Bacteria and their applications in the food industry

BACKGROUND

Lactic Acid Bacteria (LAB) are commonly used as starter cultures, probiotics, to produce lactic acid and other useful compounds, and even as natural preservatives. For use in any food product however, LAB need to survive the various stresses they encounter in the environment and during processing. Understanding these mechanisms may enable direction of LAB biochemistry with potential beneficial impact for the food industry.

AIM OF REVIEW

To give an overview of the use of LAB in the food industry and then generate a deeper biochemical understanding of LAB stress response mechanisms via metabolomics, and methods of screening for robust strains of LAB.

KEY SCIENTIFIC CONCEPTS OF REVIEW

Uses of LAB in food products were assessed and factors which contribute to survival and tolerance in LAB investigated. Changes in the metabolic profiles of LAB exposed to stress were found to be associated with carbohydrates, amino acids and fatty acid levels and these changes were proposed to be a result of the bacteria trying to maintain cellular homeostasis in response to external conditions and minimise cellular damage from reactive oxygen species. This correlates with morphological analysis which shows that LAB can undergo cell elongation and shortening, as well as thinning and thickening of cell membranes, when exposed to stress. It is proposed that these innate strategies can be utilised to minimise negative effects caused by stress through selection of intrinsically robust strains, genetic modification and/or prior exposure to sublethal stress. This work demonstrates the utility of metabolomics to the food industry.

Investigating the Efficacy of Saccharomyces boulardii in Metabolic Syndrome Treatment: A Narrative Review of What Is Known So Far

Metabolic syndrome (MetS) is characterized by complex metabolic changes involving a cluster of co-occurring conditions, such as abdominal obesity, high blood pressure, high fasting plasma glucose, high serum triglycerides, and high LDL cholesterol levels or low HDL cholesterol levels. The incidence and risk factors of MetS occurrence increase every year. It is estimated that MetS affects approximately 30% of the population of some countries. Therefore, novel strategies are being studied to reduce the negative impact of having an unbalanced diet and a lack of physical activity. One of these strategies is the administration of probiotic microorganisms, such as the yeast Saccharomyces boulardii, which has been associated with several beneficial health effects (including modulation of the intestinal microbiota and improvement of the inflammatory, antioxidant, antibacterial, antitumor, and anti-inflammatory profiles). Thus, the objective of this study was to review the risk factors of MetS occurrence and the beneficial effects of S. boulardii ingestion in the treatment of MetS. Here, we critically evaluate the treatment necessary to promote these benefits. Using the pre-established inclusion criteria, eight studies were reviewed, including five animal and three human studies. The results reported the regulation of the lipid profile, modulation of the intestinal microbiota and gene expression, and a decrease in mass gain as positive results when S. boulardii was administered. Although more experiments are needed to validate these results, especially using human models, there is a trend toward improvement in MetS and a reduction in its risk factors with the administration of S. boulardii.

Identification of the Intestinal Microbes Associated with Locomotion

Given the impact of the gut microbiome on human physiology and aging, it is possible that the gut microbiome may affect locomotion in the same way as the host's own genes. There is not yet any direct evidence linking the gut microbiome to locomotion, though there are some potential connections, such as regular physical activity and the immune system. In this study, we demonstrate that the gut microbiome can contribute differently to locomotion. We remodeled the original gut microbiome of mice through fecal microbiota transplantation (FMT) using human feces and compared the changes in locomotion of the same mice before and three months after FMT. We found that FMT affected locomotion in three different ways: positive, none (the same), and negative. Analysis of the phylogenesis, α-diversities, and β-diversities of the gut microbiome in the three groups showed that a more diverse group of intestinal microbes was established after FMT in each of the three groups, indicating that the human gut microbiome is more diverse than that of mice. The FMT-remodeled gut microbiome in each group was also different from each other. Fold change and linear correlation analyses identified Lacrimispora indolis, Pseudoflavonifractor phocaeensis, and Alistipes senegalensis in the gut microbiome as positive contributors to locomotion, while Sphingobacterium cibi, Prevotellamassilia timonensis, Parasutterella excrementihominis, Faecalibaculum rodentium, and Muribaculum intestinale were found to have negative effects. This study not only confirms the presence of gut microbiomes that contribute differently to locomotion, but also explains the mixed results in research on the association between the gut microbiome and locomotion.

Efficacy and Safety of the Adjuvant Use of Probiotic Bacillus clausii Strains in Pediatric Irritable Bowel Syndrome: A Randomized, Double-Blind, Placebo-Controlled Study

OBJECTIVES

Current irritable bowel syndrome (IBS) treatments have limited efficacy and probiotics like Bacillus clausii (B. clausii) were found to be effective in the management of several gastrointestinal disorders. This phase III trial assessed the efficacy and safety of adding B. clausii (four strains: O/C, N/R, SIN, T), versus placebo, to conventional treatment of pediatric IBS in Mexico.

METHODS

Patients aged 6-17 years 11 months with IBS (Rome IV) for at least 2 months were randomized to receive either B. clausii (oral suspension, total dose 4 billion spores/day) or placebo once daily for 8 weeks. All patients also received conventional treatment. The primary endpoint was the difference in the proportion of patients with clinical improvements at Week 8 (Global Assessment Questions [GAQ]). Secondary endpoints included responders by Subject's Global Assessment of Relief for Children with IBS (SGARC); number/consistency of stools; abdominal distention/bloating; abdominal pain/intensity; and IBS behavior.

RESULTS

73.6% (95% confidence interval [CI] 67.3-80.0; B. clausii n = 129) and 78.5% (95% CI 72.5-84.4; placebo n = 130) of patients had symptom improvement (p = 0.8182). For Week 8 SGARC, 19.2% (B. clausii) and 20.9% (placebo) reported complete symptom relief. Stool evaluations, bloating, abdominal pain/intensity, and IBS behavior were similar between groups. Both treatments were well tolerated.

CONCLUSION

No significant differences in efficacy between B. clausii and placebo were demonstrated in addition to conventional treatment. The sample size calculation was based on an expected placebo/conventional treatment response of 30-40%. However, the actual treatment response observed was 80% and, thus, a study with larger population would be warranted. In addition, this study was conducted during the COVID-19 pandemic, when such controlled social conditions may have resulted in better diet, greater family stability, less psychological stress, and lower risk of infections exacerbating IBS, thereby improving symptoms in both groups.

EUDRACT NUMBER

2018-004519-31.

Machine Learning Algorithms Highlight tRNA Information Content and Chargaff’s Second Parity Rule Score as Important Features in Discriminating Probiotics from Non-Probiotics

Simple Summary

Probiotics are a group of beneficial microorganisms that are symbionts of the human gut microbiome. The identification of new probiotics is therefore of paramount importance from both public health and commercial perspectives. In this study, we show for the first time that Artificial Intelligence algorithms can identify novel probiotics and also discriminate them from pathogenic organisms in the human gut. We were also able to determine the information content within tRNA sequences as the key genomic features capable of characterizing probiotics.

Abstract

Probiotic bacteria are microorganisms with beneficial effects on human health and are currently used in numerous food supplements. However, no selection process is able to effectively distinguish probiotics from non-probiotic organisms on the basis of their genomic characteristics. In the current study, four Machine Learning algorithms were employed to accurately identify probiotic bacteria based on their DNA characteristics. Although the prediction accuracies of all algorithms were excellent, the Neural Network returned the highest scores in all the evaluation metrics, managing to discriminate probiotics from non-probiotics with an accuracy greater than 90%. Interestingly, our analysis also highlighted the information content of the tRNA sequences as the most important feature in distinguishing the two groups of organisms probably because tRNAs have regulatory functions and might have allowed probiotics to evolve faster in the human gut environment. Through the methodology presented here, it was also possible to identify seven promising new probiotics that have a higher information content in their tRNA sequences compared to non-probiotics. In conclusion, we prove for the first time that Machine Learning methods can discriminate human probiotic from non-probiotic organisms underlining information within tRNA sequences as the most important genomic feature in distinguishing them.

Effectiveness and Safety of Probiotics for Patients with Constipation-Predominant Irritable Bowel Syndrome: A Systematic Review and Meta-Analysis of 10 Randomized Controlled Trials

To perform a systematic review and meta-analysis to evaluate the effectiveness and safety of probiotics in the treatment of constipation-predominant irritable bowel syndrome (IBS-C), we searched for randomized controlled trials (RCTs) comparing probiotic care versus placebos for patients with IBS-C in five comprehensive databases (March 2022). The risk of bias was assessed using the Cochrane Collaboration Risk of Bias Tool. RevMan 5.3 was used to perform a meta-analysis on stool consistency, abdominal pain, bloating, quality of life (QoL), fecal Bifidobacterium and Lactobacillus counts, and adverse events. The GRADE approach was used to evaluate the certainty of the evidence. Ten RCTs involving 757 patients were included. Only three studies were rated as having a low risk of bias. The meta-analysis results show that, compared to the placebo, probiotics significantly improved stool consistency (MD = 0.72, 95% CI (0.18, 1.26), p < 0.05, low quality) and increased the number of fecal Bifidobacteria (MD = 1.75, 95% CI (1.51, 2.00), p < 0.05, low quality) and Lactobacillus (MD = 1.69, 95% CI (1.48, 1.89), p < 0.05, low quality), while no significant differences were found in abdominal pain scores, bloating scores, QoL scores, or the incidence of adverse events (p > 0.05). The low-to-very low certainty evidence suggests that probiotics might improve the stool consistency of patients with IBS-C and increase the number of Bifidobacteria and Lactobacilli in feces with good safety. However, more high-quality studies with large samples are needed to verify the findings.

Limosilactobacillus reuteri in Health and Disease

Limosilactobacillus reuteri is a microorganism with valuable probiotic qualities that has been widely employed in humans to promote health. It is a well-studied probiotic bacterium that exerts beneficial health effects due to several metabolic mechanisms that enhance the production of anti-inflammatory cytochines and modulate the gut microbiota by the production of antimicrobial molecules, including reuterin. This review provides an overview of the data that support the role of probiotic properties, and the antimicrobial and immunomodulatory effects of some L. reuteri strains in relation to their metabolite production profile on the amelioration of many diseases and disorders. Although the results discussed in this paper are strain dependent, they show that L. reuteri, by different mechanisms and various metabolites, may control body weight and obesity, improve insulin sensitivity and glucose homeostasis, increase gut integrity and immunomodulation, and attenuate hepatic disorders. Gut microbiota modulation by ingesting probiotic L. reuteri strains could be a promising preventative and therapeutic approach against many diseases and disorders.

Gastrointestinal Microbiota Dysbiosis Associated with SARS-CoV-2 Infection in Colorectal Cancer: The Implication of Probiotics

The complexity of coronavirus disease 2019 (COVID-19)’s pathophysiology is such that microbial dysbiosis in the lung and gastrointestinal (GI) microbiota may be involved in its pathogenic process. GI microbiota dysbiosis has been associated with respiratory disorders, including COVID-19, as well as sporadic colorectal cancer (CRC) through imbalanced microbiota and compromised immune response. It is pertinent to understand the possible role of probiotics in stabilizing the microbial environment and maintaining the integrity of the respiratory and GI tracts in SARS-CoV-2 induced dysbiosis and colorectal carcinogenesis. The long-term implication of SARS-CoV-2 in GI dysbiosis via microbiota-gut-lung cross-talk could increase the risk of new CRC diagnosis or worsen the condition of previously diagnosed individuals. Recent knowledge shows that the immune-modulatory response to probiotics is shifting the beneficial use of probiotics towards the treatment of various diseases. In this review, we highlight the potential impact of probiotics on SARS-CoV-2 infection associated with CRC through microbiota imbalance in COVID-19 patients.

The crucial role of oxidative stress in non-alcoholic fatty liver disease-induced male reproductive toxicity: the ameliorative effects of Iranian indigenous probiotics

Several studies have focused on the high potential effects of probiotics on the reproductive system. However, there is a paucity of information regarding the ameliorative intracellular roles of indigenous Iranian yogurt-extracted/cultured probiotics on animals' reproductive health suffering from obesity and/or fatty liver disease, such as non-alcoholic fatty liver disease (NAFLD). For this purpose, simultaneously with the consumption of D-fructose (200 g/1000 mL water, induction of NAFLD model), all pubertal animals were also gavaged every day for 63 consecutive days with extracted probiotics, including 1 × 109 CFU/mL of Lactobacillus acidophilus (LA), Bifidobacterium spp. (BIF), Bacillus coagulans (BC), Lactobacillus rhamnosus (LR), and a mixture form (LA + BIF + BC + LR). At the end of the ninth week, the indices of epididymal sperm, and oxidative stress, as well as histopathological changes, were assessed. The results show that NAFLD could induce robust oxidative stress, highlighted as considerable increments in ROS level, TBARS content, total oxidized protein levels, along with severe decrements in reduced glutathione reservoirs, total antioxidant capacity in the hepatic and testicular tissues, as well as testicular and hepatic histopathological alterations. Moreover, a significant decrease in the percentage of sperm progressive motility, sperm count, and membrane integrity along with an increment in the percentage of sperm abnormality was detected in NAFLD animals. The observed adverse effects were significantly reversed upon probiotics treatment, especially in the group challenged with a mixture of all probiotics. Taken together, these findings indicate that the indigenous yogurt-isolated/cultured probiotics had a high potential antioxidant activity and the ameliorative effect against reprotoxicity and blood biochemical alterations induced by the NAFLD model. Highlights: 1. Reproductive indices could be reversely affected by xenobiotics and diseases. 2. NAFLD and cholestasis considerably affect the reproductive system in both genders. 3. NAFLD induced hepatic and testicular oxidative stress (OS). 4. NAFLD induced histopathological alterations and spermatotoxicity through OS. 5. The adverse effects were significantly reversed upon exposure to probiotics.

Long-Term Effects of a Web-Based Low-FODMAP Diet Versus Probiotic Treatment for Irritable Bowel Syndrome, Including Shotgun Analyses of Microbiota: Randomized, Double-Crossover Clinical Trial

BACKGROUND

The long-term management of irritable bowel syndrome (IBS) poses many challenges. In short-term studies, eHealth interventions have been demonstrated to be safe and practical for at-home monitoring of the effects of probiotic treatments and a diet low in fermentable oligosaccharides, disaccharides, monosaccharides, and polyols (FODMAPs). IBS has been linked to alterations in the microbiota.

OBJECTIVE

The aim of this study was to determine whether a web-based low-FODMAP diet (LFD) intervention and probiotic treatment were equally good at reducing IBS symptoms, and whether the response to treatments could be explained by patients' microbiota.

METHODS

Adult IBS patients were enrolled in an open-label, randomized crossover trial (for nonresponders) with 1 year of follow-up using the web application IBS Constant Care (IBS CC). Patients were recruited from the outpatient clinic at the Department of Gastroenterology, North Zealand University Hospital, Denmark. Patients received either VSL#3 for 4 weeks (2 × 450 billion colony-forming units per day) or were placed on an LFD for 4 weeks. Patients responding to the LFD were reintroduced to foods high in FODMAPs, and probiotic responders received treatments whenever they experienced a flare-up of symptoms. Treatment response and symptom flare-ups were defined as a reduction or increase, respectively, of at least 50 points on the IBS Severity Scoring System (IBS-SSS). Web-based ward rounds were performed daily by the study investigator. Fecal microbiota were analyzed by shotgun metagenomic sequencing (at least 10 million 2 × 100 bp paired-end sequencing reads per sample).

RESULTS

A total of 34 IBS patients without comorbidities and 6 healthy controls were enrolled in the study. Taken from participating subjects, 180 fecal samples were analyzed for their microbiota composition. Out of 21 IBS patients, 12 (57%) responded to the LFD and 8 (38%) completed the reintroduction of FODMAPs. Out of 21 patients, 13 (62%) responded to their first treatment of VSL#3 and 7 (33%) responded to multiple VSL#3 treatments. A median of 3 (IQR 2.25-3.75) probiotic treatments were needed for sustained symptom control. LFD responders were reintroduced to a median of 14.50 (IQR 7.25-21.75) high-FODMAP items. No significant difference in the median reduction of IBS-SSS for LFD versus probiotic responders was observed, where for LFD it was -126.50 (IQR -196.75 to -76.75) and for VSL#3 it was -130.00 (IQR -211.00 to -70.50; P>.99). Responses to either of the two treatments were not able to be predicted using patients' microbiota.

CONCLUSIONS

The web-based LFD intervention and probiotic treatment were equally efficacious in managing IBS symptoms. The response to treatments could not be explained by the composition of the microbiota. The IBS CC web application was shown to be practical, safe, and useful for clinical decision making in the long-term management of IBS. Although this study was underpowered, findings from this study warrant further research in a larger sample of patients with IBS to confirm these long-term outcomes.

TRIAL REGISTRATION

ClinicalTrials.gov NCT03586622; https://clinicaltrials.gov/ct2/show/NCT03586622.

Strain-specific and outcome-specific efficacy of probiotics for the treatment of irritable bowel syndrome: A systematic review and meta-analysis

BACKGROUND

Consistent guidance for choosing an appropriate probiotic for the treatment of irritable bowel syndrome is lacking.

METHODS

Literature databases searched included: PubMed, Google Scholar and NIH registry of clinical trials from inception to June 2021. Inclusion criteria: randomized controlled trials (RCTs) enrolling adult or pediatric IBS patients comparing probiotics against controls and ≥ 2 RCTs with common IBS outcome measures within each type of probiotic. Five common measures of IBS symptoms (changes in global Irritable Bowel Syndrome Severity Scoring System or IBS-SSS scores, frequency of global responders, changes in bloating or abdominal pain scores and frequency of abdominal pain relief) were used. This study was registered at Prospero (#CRD42018109169).

FINDINGS

We screened 521 studies and included 42 randomized controlled trials (45 treatment arms, N = 3856). Four probiotics demonstrated significant reduction in abdominal pain relief: B. coagulans MTCC5260 (RR= 4.9, 95% C.I. 3.3, 7.3), L. plantarum 299v (RR= 4.6, 95% CI 1.9, 11.0), S. boulardii CNCM I-745 (RR= 1.5, 95% C.I. 1.1, 2.1) and S. cerevisiae CNCM I-3856 (RR= 1.3, 95% C.I. 1.04, 1.6). Mild-moderate adverse events were reported in 51% of the trials, none were more associated with the probiotic compared to controls.

INTERPRETATION

Although the analysis of probiotic efficacy was limited by the diversity of IBS outcomes used in trials and lack of confirmatory trials for some strains, six single-strain probiotics and three different types of probiotic mixtures showed significant efficacy for at least one IBS outcome measure. These results might be relevant to clinical practice and policy.

The Effect of Bifidobacterium on Reducing Symptomatic Abdominal Pain in Patients with Irritable Bowel Syndrome: A Systematic Review

Probiotics, specifically Bifidobacteria, may improve abdominal pain in patients with irritable bowel syndrome (IBS); however, results from randomised controlled trials (RCTs) are conflicting. Here, we systematically reviewed the efficacy of Bifidobacteria on abdominal pain in IBS. We searched MEDLINE, EMBASE and the Cochrane Controlled Trials Register from inception to 20 May 2019, without language or date restrictions. The search strategy comprised of the combination of three concepts: supplementation, abdominal pain, and IBS. Inclusion criteria included double-blind placebo-controlled RCTs featuring Bifidobacteria supplementation in Rome-diagnosed IBS patients. A total of 8 RCTs involving a total of 1045 patients with Rome diagnosed IBS were included. The dose of total Bifidobacteria ranged from 10⁶ to > 10¹¹ cfu (colony-forming unit) and duration of supplementation ranged between 2 and 8 weeks. Bifidobacteria was delivered through either intake of fermented milk products, encapsulation or via a malted milk beverage, with all studies assessing abdominal pain via a visual analogue Likert scale. From the studies included, 50% (n = 4) of studies found a statistically significant improvement in abdominal pain following Bifidobacteria supplementation compared to placebo, 38% (n = 3) of studies found non-significant improvements and 12% (n = 1) showed a statistically significant dose-response effect of improvement. The evidence shows a heterogeneity of effect for Bifidobacteria dependent upon strain, dosage and delivery method. While not all studies demonstrate significant improvements in abdominal pain, none of the selected studies reported an increase in pain or other adverse effects.

Development and validation of the Health Promoting Behaviour for Bloating (HPB-Bloat) scale

Background

Health management strategies may help patients with abdominal bloating (AB), but there are currently no tools that measure behaviour and awareness. This study aimed to validate and verify the dimensionality of the newly-developed Health Promoting Behaviour for Bloating (HPB-Bloat) scale.

Methods

Based on previous literature, expert input, and in-depth interviews, we generated new items for the HPB-Bloat. Its content validity was assessed by experts and pre-tested across 30 individuals with AB. Construct validity and dimensionality were first determined using exploratory factor analysis (EFA) and Promax rotation analysis, and then using confirmatory factor analysis (CFA).

Results

During the development stage, 35 items were generated for the HPB-Bloat, and were maintained following content validity assessment and pre-testing. One hundred and fifty-two participants (mean age of 31.27 years, 68.3% female) and 323 participants (mean age of 27.69 years, 59.4% male) completed the scale for EFA and CFA, respectively. Using EFA, we identified 20 items that we divided into five factors: diet (five items), health awareness (four items), physical activity (three items), stress management (four items), and treatment (four items). The total variance explained by the EFA model was 56.7%. The Cronbach alpha values of the five factors ranged between 0.52 and 0.81. In the CFA model, one problematic latent variable (treatment) was identified and three items were removed. In the final measurement model, four factors and 17 items fit the data well based on several fit indices (root mean square error of approximation (RMSEA) = 0.044 and standardized root mean squared residual (SRMR) = 0.052). The composite reliability of all factors in the final measurement model was above 0.60, indicating acceptable construct reliability.

Conclusion

The newly developed HPB-Bloat scale is valid and reliable when assessing the awareness of health-promoting behaviours across patients with AB. Further validation is needed across different languages and populations.

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.

The Evolving Role of Gut Microbiota in the Management of Irritable Bowel Syndrome: An Overview of the Current Knowledge

The intestinal microbiota is one of the most rapidly evolving areas in biology and medicine. Extensive research in the last decade has escalated our understanding of the role of the microbiota in the pathogenesis of several intestinal and extra-intestinal disorders. Marked by high prevalence, substantial morbidity, and enormous costs, irritable bowel syndrome (IBS) is an important chronic gastrointestinal disorder that is widely encountered by gastroenterologists. Despite advances in our understanding of its pathophysiology, curative interventions have yet to be discovered, and therapeutic approaches remain symptom-driven. Recently, accumulating evidence has enlightened the possible impact of an imbalanced gut microbiome in the pathogenesis of IBS. In fact, several studies have documented altered microbiota in patients, while others have shown that IBS severity was associated with a distinct microbiota signature. These findings may pave the way for the use of microbiota manipulation strategies as an attractive option for IBS management, and may have an essential role in efforts to reduce the societal and economic effects of this ever-growing disorder. In this review, we have outlined the results of the latest research on the association between microbiota and IBS and their implications for the clinical management of affected patients.

The good bugs: the use of probiotics in pediatrics

PURPOSE OF REVIEW

There is growing evidence encouraging the use of probiotics in many conditions in children. However, given the wide number of probiotics available and contradictory data in the literature, the health-care provider is often faced with uncertainness about whether or not to use probiotics and which one(s) to choose. We here review current hypotheses regarding the efficacy and safety of probiotics and evaluate the available data on the use of probiotics in most common diseases in children. Considering that probiotics have strain-specific effects, we will focus on individual probiotic strains rather than on probiotics in general.

RECENT FINDINGS

Strain-specific efficacy was clearly demonstrated with Lactobacillus rhamnosus GG and Saccharomyces boulardii I-745 in the treatment of acute infectious diarrhea, Lactobacillus reuteri DSM 17938 in infantile colics, Lactobacillus rhamnosus GG, and VSL#3 in irritable bowel syndrome. In addition, encouraging results are seen for use of probiotics in necrotizing enterocolitis, food allergy, and nonalcoholic fatty liver disease. However, the data available for constipation are to be considered somewhat equivocal.

SUMMARY

The clinical relevance of these findings indicates that healthcare providers need to take strain-specificity and disease specificity of probiotics into consideration when recommending probiotic for their patients.

Probiotics for glycemic control in patients with type 2 diabetes mellitus: protocol for a systematic review

BACKGROUND

Type 2 diabetes mellitus (T2DM) is a major public health problem worldwide. It is characterized by the increased concentration of glucose in the blood and leads to damage of the body system, especially blood vessels and nerves. Lifestyle modification is often combined with anti-diabetic therapy as the standard of care for T2DM to maintain the proper blood glucose and to prevent long-term diabetic complications. The role of probiotics in improving glycemic control has been investigated in several randomized controlled trials (RCTs). Previous systematic reviews and meta-analyses, including different sets of trials have concluded an overall beneficial effect of probiotics in patients with T2DM. At least two RCTs with a longer treatment duration have been published since the publication of existing reviews.

METHODS

We will conduct a systematic review of RCTs that evaluated the effectiveness and safety of probiotics for glycemic control in T2DM patients. Primary outcomes are fasting blood glucose and glycosylated hemoglobin (A1c). Secondary outcomes are plasma insulin, blood lipid profile, adverse events, and cost associated with the intervention and hospital visits. We will search PubMed, Embase, and the Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library, and trial registries. Two reviewers will independently screen titles and abstracts, review full texts, extract information, and assess the risk of bias. We will summarize the results both qualitatively and statistically. We will use random-effects model for meta-analysis.

DISCUSSION

This systematic review aims to examine whether probiotics are effective and safe for glycemic control in T2DM patients. Evidence generated from this review will inform clinical and public health practice and future research.

SYSTEMATIC REVIEW REGISTRATION

CRD42019121682.

Pharmacological and non-pharmacological treatments for irritable bowel syndrome: Protocol for a systematic review and network meta-analysis

BACKGROUND

The global prevalence of Irritable bowel syndrome (IBS) is estimated to be as high as 15% and a number of different non-pharmacological and pharmacological treatments have been used to manage IBS in clinical practice, which poses great challenges for clinicians to make appropriate decisions. Hence, a systematic review and network meta-analysis on all available pharmacological and non-pharmacological treatments for IBS is needed to provide reliable evidence.

METHODS

We will search the Cochrane Central Register of Controlled Trials (CENTRAL), the Cochrane IBD Group Specialized Trials Register, MEDLINE, EMBASE, and Chinese Biomedical medicine (CBM) from inception to 31, May 2019. Randomized controlled trials of pharmacological and nonpharmacological interventions for IBS will be included. Study quality will be assessed on the basis of the methodology and categories described in the Cochrane Collaboration Handbook. Primary outcomes are global or clinical improvement and quality of life. A Bayesian network meta-analysis would be performed, and relative ranking of agents would be assessed. A node splitting method will be used to examine the inconsistency between direct and indirect comparisons when a loop connecting 3 arms exists.

RESULTS

Researchers will rank the effectiveness and safety of the potentials interventions for IBS according the characteristics of patients by conducting an advanced network meta-analysis based on Bayesian statistical model, and interpret the results by using GRADE approach.

CONCLUSION

The conclusion of our study will provide updated evidence to rank the effectiveness and safety of pharmacological and non-pharmacological interventions for IBS.

ETHICS AND DISSEMINATION

Ethical approval is not applicable since this study is a network meta-analysis based on published trials.

PROTOCOL REGISTRATION NUMBER

CRD42018083844.

The Case for a More Holistic Approach to Dry Eye Disease: Is It Time to Move beyond Antibiotics?

Dry eye disease (DED) is one of the most frequent presentations to optometrists with over 16 million US adults (6.8% of adult population) diagnosed as having this disorder. The majority of associated marketed products offer relief from symptomatology but do not address aetiology. DED harbours many distinguishing features of a chronic inflammatory disorder. The recent explosion in human microbiome research has sparked interest in the ocular microbiome and its role in the preservation and extension of ocular surface health and in the contribution of the gut microbiome to chronic systemic inflammation and associated "Western life-style" diseases. With a significant lack of success for many patients using currently available DED treatments, in this era of the microbiome, we are interested in exploring potential novel therapies that aim to reconstitute healthy bacterial communities both locally and distally (in the gut) as a treatment for DED. Although this direction of investigation is in its infancy, burgeoning interest makes such a review timely. This paper considers a number of studies into the use functional foods and associated products to ameliorate dry eye.

Dopamine production in Enterococcus faecium: A microbial endocrinology-based mechanism for the selection of probiotics based on neurochemical-producing potential

The mechanisms by which probiotics may influence host physiology are still incompletely understood. Microbial endocrinology, a field representing the union of microbiology, endocrinology and neurobiology, has theorized that microorganisms have the capacity to serve as neurochemical delivery vehicles [1]. According to microbial endocrinology, neurochemicals can serve as a common language between host and bacterium, enabling bidirectional communication. We report herein the first demonstration that Enterococcus sp. has the capacity to produce dopamine in a gastrointestinal-like environment when supplied with the dopamine precursor L-3,4 dihydroxyphenylalanine (L-dopa). The results presented herein provide a means to select probiotics based on neurochemical-producing potential and suggest the possibility that probiotics containing E. faecium may serve to influence the host through dopaminergic pathways.

A Randomized Clinical Trial of Synbiotics in Irritable Bowel Syndrome: Dose-Dependent Effects on Gastrointestinal Symptoms and Fatigue

Background

This double-blind, randomized controlled design study aimed to assess the dose-dependent effects of synbiotics on gastrointestinal symptoms of and fatigue in irritable bowel syndrome (IBS).

Methods

Thirty subjects with IBS were randomly assigned into the following three groups and received 2 capsules a day for 8 weeks: (1) high-dose (2 capsules of synbiotics); (2) low-dose (1 capsule of synbiotics and 1 capsule of placebo); and (3) placebo (2 capsules of placebo). At baseline and 8 weeks, they completed the study questionnaires.

Results

Two subjects in the high-dose group were lost to follow-up, leaving a total of 28 patients for the analysis. After 8 weeks, abdominal discomfort, abdominal bloating, frequency of formed stool, fatigue Visual Analog Scale (VAS), and Multidimensional Fatigue Inventory were significantly different among the groups (P=0.002, 0.006, 0.007, 0.028, and 0.041, respectively, by Kruskal-Wallis test). However, only abdominal discomfort, abdominal bloating, frequency of formed stool, and fatigue VAS were significantly improved in the high-dose group compared with those in the placebo group (P=0.002, 0.003, 0.002, and 0.013, respectively) by Mann-Whitney test with Bonferroni correction. No adverse drug reactions were reported.

Conclusion

High-dose synbiotics were superior to placebo in improving bowel symptoms and fatigue of IBS patients, suggesting that synbiotic dosage plays an important role in the treatment of IBS.

Management of Functional Somatic Syndromes and Bodily Distress

Functional somatic syndromes (FSS), like irritable bowel syndrome or fibromyalgia and other symptoms reflecting bodily distress, are common in practically all areas of medicine worldwide. Diagnostic and therapeutic approaches to these symptoms and syndromes vary substantially across and within medical specialties from biomedicine to psychiatry. Patients may become frustrated with the lack of effective treatment, doctors may experience these disorders as difficult to treat, and this type of health problem forms an important component of the global burden of disease. This review intends to develop a unifying perspective on the understanding and management of FSS and bodily distress. Firstly, we present the clinical problem and review current concepts for classification. Secondly, we propose an integrated etiological model which encompasses a wide range of biopsychosocial vulnerability and triggering factors and considers consecutive aggravating and maintaining factors. Thirdly, we systematically scrutinize the current evidence base in terms of an umbrella review of systematic reviews from 2007 to 2017 and give recommendations for treatment for all levels of care, concentrating on developments over the last 10 years. We conclude that activating, patient-involving, and centrally acting therapies appear to be more effective than passive ones that primarily act on peripheral physiology, and we recommend stepped care approaches that translate a truly biopsychosocial approach into actual management of the patient.

The gut microbiome and irritable bowel syndrome: State of art review

Irritable bowel syndrome (IBS) is a functional disorder of the gastrointestinal tract, the physiology of which is not very well understood. There are multiple factors and pathways involved in pathogenesis of this entity. Among all, dysmotility, dysregulation of the brain-gut axis, altered intestinal microbiota and visceral hypersensitivity play a major role. Over the last years, research has shown that the type of gut microbiome present in an individual plays a significant role in the pathophysiology of IBS. Multiple studies have consistently shown that subjects diagnosed with IBS have disruption in gut microbiota balance. It has been established that host immune system and its interaction with metabolic products of gut microbiota play an important role in the gastrointestinal tract. Therefore, probiotics, prebiotics and antibiotics have shown some promising results in managing IBS symptoms via modulating the interaction between the above. This paper discusses the various factors involved in pathophysiology of IBS, especially gut microbiota.

Lactobacillus acidophilus CL1285, Lactobacillus casei LBC80R and Lactobacillus rhamnosus CLR2 improve quality-of-life and IBS symptoms: a double-blind, randomised, placebo-controlled study

A combination of Lactobacillus acidophilus CL1285, Lactobacillus casei LBC80R and Lactobacillus rhamnosus CLR2 was compared to placebo for relief of symptoms of irritable bowel syndrome (IBS). A total of 113 subjects at 3 clinical sites were randomised in a 2:1 ratio and followed for 12 weeks. Subjects ingested either 2 capsules of active study product, containing 50×10⁹ cfu of live organisms, or 2 placebo capsules daily. Endpoints included improvement in abdominal pain, days of pain, distention, stool consistency and frequency, quality of life (QOL), and adequate relief (AR) of IBS symptoms. IBS subtypes constipation (IBS-C), diarrhoea (IBS-D), and mixed (IBS-M) were evaluated separately; the effect of gender was also examined. For all efficacy endpoints improvement of 30% or more vs placebo was considered clinically significant. With the exception of pain intensity and AR, the endpoints demonstrated a therapeutic advantage of active over placebo for IBS symptoms in at least some subject subgroups. The IBS-D and female subgroups showed the largest and most consistent effects. Stool frequency and consistency were evaluated in the IBS-C and IBS-D subgroups, and improvement of active vs placebo was noted in both. QOL improvement was seen overall and in specific domains. Adverse events (AEs) were limited to 7 subjects; all were of mild or moderate intensity except one, severe cramping. Four AEs in the same subject in the placebo group were judged to be related to study product; these resolved by the end of study. There were no serious AEs.

Effect of Lactobacillus rhamnosus GG supernatant on serotonin transporter expression in rats with post-infectious irritable bowel syndrome

AIM

To evaluate the effect of Lactobacillus rhamnosus GG supernatant (LGG-s) on the expression of serotonin transporter (SERT) in rats with post-infectious irritable bowel syndrome (PI-IBS).

METHODS

Campylobacter jejuni 81-176 (10¹⁰ CFU/mL) was used to induce intestinal infection to develop a PI-IBS model. After evaluation of the post-infectious phase by biochemical tests, DNA agarose gel electrophoresis, abdominal withdrawal reflex (AWR) test, and the intestinal motility test, four PI-IBS groups received different concentrations of LGG-s for 4 wk. The treatments were maintained for 1.0, 2.0, 3.0 or 4.0 wk during the experiment, and the colons and brains were removed for later use each week. SERT mRNA and protein levels were detected by real-time PCR and Western blot, respectively.

RESULTS

The levels of SERT mRNA and protein in intestinal tissue were higher in rats treated with LGG-s than in control rats and PI-IBS rats gavaged with PBS during the whole study. Undiluted LGG-s up-regulated SERT mRNA level by 2.67 times compared with the control group by week 2, and SERT mRNA expression kept increasing later. Double-diluted LGG-s was similar to undiluted-LGG-s, resulting in high levels of SERT mRNA. Triple-diluted LGG-s up-regulated SERT mRNA expression level by 6.9-times compared with the control group, but SERT mRNA expression decreased rapidly at the end of the second week. At the first week, SERT protein levels were basically comparable in rats treated with undiluted LGG-s, double-diluted LGG-s, and triple-diluted LGG-s, which were higher than those in the control group and PBS-treated PI-IBS group. SERT protein levels in the intestine were also comparable in rats treated with undiluted LGG-s, double-diluted LGG-s, and triple-diluted LGG-s by the second and third weeks. SERT mRNA and protein levels in the brain had no statistical difference in the groups during the experiment.

CONCLUSION

LGG-s can up-regulate SERT mRNA and protein levels in intestinal tissue but has no influence in brain tissue in rats with PI-IBS.

Gut dysbiosis and irritable bowel syndrome: The potential role of probiotics

OBJECTIVE

To discuss the role of gut dysbiosis in the development of irritable bowel syndrome (IBS) and the impact of probiotics as a potential therapeutic measure.

METHODS

PubMed was used to search for all of the studies published over the last 15 years using the key words: "irritable bowel syndrome" and "gut dysbiosis" or "probiotic". More than 800 articles were found, but only those published in English or providing evidence-based data were included in the evaluation.

RESULTS

IBS is a common disease for which no resolutive therapy is presently available. In recent years, strong evidence of a possible relationship between modifications of the gut microbiota composition and development of IBS has been collected. Moreover, the evidence showed that attempts to treat acute infectious and post-antibiotic gastroenteritis with some probiotics were significantly effective in a great number of patients, leading many experts to suggest the use of probiotics to address all of the clinical problems associated with IBS.

CONCLUSION

The available data are promising, but presently, a precise definition of which probiotic or which mixture of probiotics is effective cannot be made. Moreover, the dose and duration of treatment has not been established. Finally, we do not know whether probiotic treatment should be different according to the type of IBS. Further studies are needed before probiotics can be considered a reliable treatment for IBS.

Gastrointestinal and Hepatic Disease in Fibromyalgia

Fibromyalgia (FM) has historically been associated with several diseases in gastroenterology and hepatology. The most substantiated evidence pertains to irritable bowel syndrome (IBS). The pathogeneses of FM and IBS remain unclear, but it is likely related to dysregulation within the brain-gut axis, resulting in a hyperalgesic state. IBS and FM share other similarities, including a female predominance, fatigue, insomnia, and susceptibility to psychiatric state. These common manifestations and pathogeneses serve as a foundation for overlapping, multidisciplinary treatment modalities.

From clinical uncertainties to precision medicine: the emerging role of the gut barrier and microbiome in small bowel functional diseases

Over the last decade, remarkable progress has been made in the understanding of disease pathophysiology. Many new theories expound on the importance of emerging factors such as microbiome influences, genomics/omics, stem cells, innate intestinal immunity or mucosal barrier complexities. This has introduced a further dimension of uncertainty into clinical decision-making, but equally, may shed some light on less well-understood and difficult to manage conditions. Areas covered: Comprehensive review of the literature on gut barrier and microbiome relevant to small bowel pathology. A PubMed/Medline search from 1990 to April 2017 was undertaken and papers from this range were included. Expert commentary: The scenario of clinical uncertainty is well-illustrated by functional gastrointestinal disorders (FGIDs). The movement towards achieving a better understanding of FGIDs is expressed in the Rome IV guidelines. Novel diagnostic and therapeutic protocols focused on the GB and SB microbiome can facilitate diagnosis, management and improve our understanding of the underlying pathological mechanisms in FGIDs.

A double-blind, placebo-controlled study to assess the effect of a probiotic mixture on symptoms and inflammatory markers in women with diarrhea-predominant IBS

BACKGROUND

Micro-inflammation is considered an element in the pathogenesis of irritable bowel syndrome (IBS). High-sensitivity C reactive protein (hs-CRP) was previously shown to be higher in IBS compared to healthy controls, albeit within the normal range. Since probiotics may suppress micro-inflammation in the gut, we tested if they reduce symptoms and inflammatory markers (hs-CRP and fecal calprotectin (FC) in diarrhea-predominant IBS (IBS-D). The aim of this study was to assess the clinical and laboratory effects of BIO-25, a multispecies probiotic, in women with IBS-D.

METHODS

A double-blind, placebo-controlled study. Following a 2-week run-in, eligible women were assigned at random to a probiotic capsule or an indistinguishable placebo, twice daily for 8 weeks. IBS symptoms and stool consistency were rated daily by Visual Analogue Scales (VAS) and the Bristol Stool Scale (BSS). High-sensitivity C reactive protein was tested at baseline, 4 and 8 weeks. FC was tested at baseline and 8 weeks.

KEY RESULTS

One hundred and seventy-two IBS-D patients were recruited and 107 eligible patients were allocated to the intervention (n=54) or placebo (n=53) group. All symptoms improved in both groups with no significant difference between them in symptom improvement, hs-CRP or FC levels.

CONCLUSIONS & INFERENCES

An 8-week treatment with BIO-25 improved symptoms in women with IBS-D, but was not superior to placebo. This rigorously designed and executed study supports the findings of other studies that did not demonstrate superiority of probiotics over placebo in IBS. High quality clinical studies are necessary to examine the efficacy of other specific probiotics in IBS-D patients since data are still conflicting.

Lactobacillus reuteri DSM 17938 in the Treatment of Functional Abdominal Pain in Children: RCT Study

OBJECTIVES

Beneficial therapeutic effect of probiotics has been reported in children with the irritable bowel syndrome (IBS) but not consistently in other functional abdominal pain-related disorders. The aim of the present study was to investigate the effect of Lactobacillus reuteri DSM 17938 in the treatment of functional abdominal pain (FAP) and IBS in children.

METHODS

Children (age 4-18 years) referred to pediatric gastroenterologist at Children's Hospital Zagreb from May 2012 to December 2014, diagnosed as FAP or IBS, were randomized to receive L reuteri DSM 17938 10⁸ CFU daily or placebo. The study was a prospective, randomized, double-blind, placebo-controlled parallel study. Symptoms were evaluated using Wong-Baker FACES pain rating scale for pain and Bristol scale for stool shape and consistence.

RESULTS

Data were analyzed for 55 children (26 in the intervention group and 29 in the placebo group). Children in the intervention group had significantly more days without pain (median 89.5 vs 51 days, P = 0.029). Abdominal pain was less severe in children taking probiotics during the second month (P < 0.05) and fourth month (P < 0.01). The 2 groups did not differ in the duration of abdominal pain, stool type, or absence from school. Both groups experienced significant reduction in the severity of abdominal pain from first to fourth month, with the reduction more prominent in the intervention group (P < 0.001 vs P = 0.004).

CONCLUSIONS

Administration of L reuteri DSM 17938 was associated with a possible reduction of the intensity of pain and significantly more days without pain in children with FAP and IBS.

The Effect of Oral Consumption of Probiotics in Prevention of Heart Injury in a Rat Myocardial Infarction Model: a Histopathological, Hemodynamic and Biochemical Evaluation

Background:

Despite the emerging evidence on beneficial effects of probiotics on the cardiovascular system, their impact on the management of ischemic heart diseases and the possible mechanism(s) have not been elucidated.

Methods:

Four viable probiotics bacterial strains, including Bifidobacterium breve, Lactobacillus casei, Lactobacillus bulgaricus, and Lactobacillus acidophilus, at the concentrations of 2×10⁶ colony-forming units/ml, were orally administered to the rats daily for 14 days before the induction of infarct-like myocardial injury using isoproterenol. Subsequently, 24 h after myocardial injury, the right carotid artery and the left ventricle were catheterized for recording blood pressure and cardiac parameters. At the end of the experiment, the heart was removed for the evaluation of histopathological and biochemical parameters, as well as tumor necrosis factor-alpha (TNF-α) assay.

Results:

The induction of acute myocardial injury resulted in significant (P≤0.01) left ventricular (LV) dysfunction, as shown by an increase in LV end-diastolic pressure and a decrease in LV dp/dt max, LV dp/dt min, LV systolic pressure, and blood pressure, as compared with normal rats. Pretreatment with viable probiotics significantly reduced lipid peroxidation and TNF-α level and improved cardiac function (P<0.01).

Conclusion:

This study shows that viable probiotics have a cardioprotective effect on infarct-like myocardial injury through suppressing TNF-α and oxidative stress damage in a rat model. Probiotic supplements may be used as a new option for prophylaxis in patients at the risk of ischemic heart disease in future.

The effects of administration of the Lactobacillus gasseri strain CP2305 on quality of life, clinical symptoms and changes in gene expression in patients with irritable bowel syndrome

AIMS

To clarify the effects of Lactobacillus gasseri CP2305 (CP2305) on quality of life and clinical symptoms and its functional mechanisms in patients with irritable bowel syndrome (IBS).

METHODS AND RESULTS

After the patients were administered CP2305 daily for 4 weeks, the IBS-severity index score was significantly improved compared with that of the placebo group, and this improvement was accompanied by a reduction in health-related worry and changes in intestinal microbiota. The gene expression profiling of the peripheral blood leucocytes showed that CP2305 treatment significantly up-regulated genes related to eukaryotic initiation factor 2 (EIF2) signalling. Eighty-two genes were down-regulated in IBS patients compared with healthy controls. The expression of 23 of these genes exhibited a CP2305-dependent increase associated with an improvement in IBS severity. The majority of the restored genes were related to EIF2 signalling.

CONCLUSIONS

CP2305 administration is a potential candidate therapeutic option for patients with IBS.

SIGNIFICANCE AND IMPACT OF THE STUDY

Although probiotics have been proposed to benefit IBS patients, objective clinical evidence and elucidation of the functional mechanism remain insufficient. Our study demonstrated that CP2305 administration beneficially influences IBS patients in both subjective and objective evaluations, and gene expression profiling provided insights into the functional mechanism.

Probiotics, prebiotics, and microencapsulation: A review

The development of a suitable technology for the production of probiotics is a key research for industrial production, which should take into account the viability and the stability of the organisms involved. Microbial criteria, stress tolerance during processing, and storage of the product constitute the basis for the production of probiotics. Generally, the bacteria belonging to the genera Lactobacillus and Bifidobacterium have been used as probiotics. Based on their positive qualities, probiotic bacteria are widely used in the production of food. Interest in the incorporation of the probiotic bacteria into other products apart from dairy products has been increasing and represents a great challenge. The recognition of dose delivery systems for probiotic bacteria has also resulted in research efforts aimed at developing probiotic food outside the dairy sector. Producing probiotic juices has been considered more in the recent years, due to an increased concern in personal health of consumers. This review focuses on probiotics, prebiotics, and the microencapsulation of living cells.

Review of the role of probiotics in gastrointestinal diseases in adults

BACKGROUND

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

OBJECTIVES

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

SEARCH METHODS

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

SELECTION CRITERIA

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

DATA COLLECTION AND ANALYSIS

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

MAIN RESULTS

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

AUTHORS' CONCLUSIONS

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

The Mexican consensus on probiotics in gastroenterology

INTRODUCTION

Probiotics are frequently prescribed in clinical practice. Their efficacy in treating gastrointestinal disorders is supported by a significant number of clinical trials. However, the correct prescription of these agents is hampered due to a lack of knowledge of the scientific evidence and to the different presentations and microbial compositions of the probiotics that are currently available.

AIM

To provide the clinician with a consensus review of probiotics and recommendations for their use in gastroenterology.

MATERIALS AND METHODS

Controlled clinical trials, meta-analyses, and systematic reviews published up to 2015 were selected, using the MESH terms: probiotics, gastrointestinal diseases, humans, adults, AND children. The Delphi method was employed. Eighteen gastroenterologists treating adult patients and 14 pediatric gastroenterologists formulated statements that were voted on until agreement>70% was reached. The level of evidence based on the GRADE system was evaluated for each statement.

RESULTS AND CONCLUSIONS

Eleven statements on the general concepts of probiotics and 27 statements on the use of probiotics in gastrointestinal diseases in both adults and children were formulated. The consensus group recommends the use of probiotics under the following clinical conditions: the prevention of diarrhea associated with antibiotics, the treatment of acute infectious diarrhea, the prevention of Clostridium difficile infection and necrotizing enterocolitis, the reduction of adverse events from Helicobacter pylori eradication therapy, relief from irritable bowel syndrome symptoms, the treatment of functional constipation in the adult, and the induction and maintenance of remission in patients with ulcerative colitis and pouchitis, and the treatment of covert and overt hepatic encephalopathy.

Saccharomyces cerevisiae CNCM I-3856 in irritable bowel syndrome: An individual subject meta-analysis

AIM

To confirm previous conclusions on Saccharomyces cerevisiae (S. cerevisiae) CNCM I-3856 for irritable bowel syndrome (IBS) management.

METHODS

An individual patient data meta-analysis was performed on two randomized clinical trials studying the effect of S. cerevisiae CNCM I-3856 supplementation on gastrointestinal (GI) symptoms in IBS subjects. A total of 579 IBS subjects were included. Outcomes were the daily Likert scale scores of abdominal pain/discomfort and bloating [area under the curve (AUC) and weekly means], responder status, and bowel movements (stool frequency and consistency). Statistical analyses were conducted in Intent to Treat (ITT) population, IBS-C subjects and IBS-C subjects with an abdominal pain/discomfort score higher than or equal to 2 at baseline ("IBS-C ≥ 2 subpopulation").

RESULTS

S. cerevisiae CNCM I-3856 significantly improved abdominal pain/discomfort and bloating during the second month of supplementation [AUC (W5-W8)] with improvement up to the minimal clinically relevant threshold of 10%: a 12.3% reduction of abdominal pain/discomfort in the ITT population compared to the Placebo group (P = 0.0134) has been observed. In the IBS-C ≥ 2 subpopulation, there were a 13.1% reduction of abdominal pain/discomfort and a 14.9% reduction of bloating compared to the Placebo group (P = 0.0194 and P = 0.0145, respectively). GI symptoms significantly decreased during supplementation but no statistical differences were reported between groups at the end of the supplementation period. Responder status was defined as a subject who experienced a decrease of 1 arbitrary unit (a.u.) or 50% of the abdominal discomfort score from baseline for at least 2 wk out of the last 4 wk of the study. A significant difference between groups was reported in the ITT population, when considering the first definition: subjects in the Active group had 1.510 higher odds to be a responder (reduction of 1 a.u. of abdominal pain/discomfort) compared with subjects in the Placebo group (P = 0.0240). At the end of supplementation period, stool consistency in the Active group of the ITT population was significantly improved and classified as "normal" compared to Placebo (respectively 3.13 ± 1.197 a.u. vs 2.58 ± 1.020 a.u., P = 0.0003). Similar results were seen in the IBS-C ≥ 2 subpopulation (Active group: 3.14 ± 1.219 a.u. vs Placebo group: 2.59 ± 1.017 a.u., P = 0.0009).

CONCLUSION

This meta-analysis supports previous data linking S. cerevisiae I-3856 and improvement of GI symptoms, in IBS overall population and in the IBS-C and IBS-C ≥ 2 subpopulations.

A Mixture of 3 Bifidobacteria Decreases Abdominal Pain and Improves the Quality of Life in Children With Irritable Bowel Syndrome: A Multicenter, Randomized, Double-Blind, Placebo-Controlled, Crossover Trial

GOALS

We assessed the efficacy of a probiotic mixture of Bifidobacterium infantis M-63, breve M-16V, and longum BB536 in improving abdominal pain (AP) and quality of life (QoL) in children with irritable bowel syndrome (IBS) and functional dyspepsia (FD).

BACKGROUND

AP-associated functional gastrointestinal disorders, particularly IBS and FD, are common in pediatrics, and no well-established treatment is currently available. Although probiotics have shown promising results in adults, data in children are heterogeneous.

STUDY

Forty-eight children with IBS (median age, 11.2 y; range, 8 to 17.9 y) and 25 with FD (age, 11.6 y; range, 8 to 16.6 y) were randomized to receive either a mixture of 3 Bifidobacteria or a placebo for 6 weeks. After a 2-week "washout" period, each patient was switched to the other group and followed up for further 6 weeks. At baseline and follow-up, patients completed a symptom diary and a QoL questionnaire. AP resolution represented the primary outcome parameter.

RESULTS

In IBS, but not in FD, Bifidobacteria determined a complete resolution of AP in a significantly higher proportion of children, when compared with placebo (P=0.006), and significantly improved AP frequency (P=0.02). The proportion of IBS children with an improvement in QoL was significantly higher after probiotics than after placebo (48% vs. 17%, P=0.001), but this finding was not confirmed in FD.

CONCLUSIONS

In children with IBS a mixture of Bifidobacterium infantis M-63, breve M-16V, and longum BB536 is associated with improvement in AP and QoL. These findings were not confirmed in FD subjects. Trial identifier: NCT02566876 (http://www.clinicaltrial.gov).